Sample records for valgus angle hva

  1. Radiographic angles in hallux valgus: differences between measurements made manually and with a computerized program.

    PubMed

    Piqué-Vidal, Carlos; Maled-García, Ignaci; Arabi-Moreno, Juanjo; Vila, Joan

    2006-03-01

    The objective of this study was to compare angular measurements in the evaluation of hallux valgus deformities using a goniometer and a computerized program to assess degree of concordance between the two methods and determine the reliability of manual measurements. Angles measured included the hallux valgus angle (HVA), the intermetatarsal angle (IMA), the distal metatarsal articular angle (DMAA), and the proximal phalangeal articular angle (PPAA), also called the hallux valgus interphalangeus angle or interphalangeal angle. Measurements were made on preoperative weightbearing radiographs in 176 patients with symptomatic hallux valgus. Manual measurements were made with a goniometer by an orthopaedic surgeon. An independent experienced technician used digitized images to perform angular measurements with the Autocad software program (Autodesk Inc., San Rafael, CA). HVA values obtained with the two techniques were similar. However, significantly higher mean values were obtained with the Autocad for the IMA and PPAA measurements, and higher mean values were obtained for the DMAA measurement with the manual technique. Whereas differences were more or less randomly distributed for the HVA, in the remaining patients, measurements were clearly related to the measurement technique, i.e., for the DMAA, the manual technique had a tendency to show higher values, and for the IMA and PPAA the manual technique showed lower values than the computer. Correlations between both techniques for the different angular measurements were as follows: HVA, -0.179 (p = 0.018); DMMA, -0.294 (p < 0.001); PPAA, -0.876 (p < 0.001); and IMA, -0.661 (p < 0.001). The intraclass correlation coefficient (ICC) showed that the concordance between manual and Autocad angular measurements was excellent for the HVA (ICC = 0.89) and DMAA (ICC = 0.80) and very poor for the PPAA (ICC = 0.11) and IMA (ICC = 0.42). Angular measurements made on weightbearing radiographs with the Autocad in patients with hallux

  2. Radiographic angles in hallux valgus: Comparison between protractor and iPhone measurements.

    PubMed

    Meng, Hong-Zheng; Zhang, Wei-Lin; Li, Xiu-Cheng; Yang, Mao-Wei

    2015-08-01

    Radiographic angles are used to assess the severity of hallux valgus deformity, make preoperative plans, evaluate outcomes after surgery, and compare results between different methods. Traditionally, hallux valgus angle (HVA) has been measured by using a protractor and a marker pen with hardcopy radiographs. The main objective of this study is to compare HVA measurements performed using a smartphone and a traditional protractor. The secondary objective was to compare the time taken between those two methods. Six observers measured major HVA on 20 radiographs of hallux valgus deformity with both a standard protractor and an Apple iPhone. Four of the observers repeated the measurements at least a week after the original measurements. The mean absolute difference between pairs of protractor and smartphone measurements was 3.2°. The 95% confidence intervals for intra-observer variability were ±3.1° for the smartphone measurement and ±3.2° for the protractor method. The 95% confidence intervals for inter-observer variability were ±9.1° for the smartphone measurement and ±9.6° for the protractor measurement. We conclude that the smartphone is equivalent to the protractor for the accuracy of HVA measurement. But, the time taken in smartphone measurement was also reduced. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  3. Use of the iPhone for radiographic evaluation of hallux valgus.

    PubMed

    Ege, Tolga; Kose, Ozkan; Koca, Kenan; Demiralp, Bahtiyar; Basbozkurt, Mustafa

    2013-02-01

    The purpose of this study was to compare the measurements made using a smartphone accelerometer and computerized measurements as a reference in a series of 32 hallux valgus patients. Two observers used an iPhone to measure the hallux valgus angle (HVA), intermetatarsal angle (IMA), and distal metatarsal articular angle (of anteroposterior foot radiographs in 32 patients with symptomatic hallux valgus on a computer screen. Digital angular measurements on the computer were set as the reference standard for analysis and comparison. The difference between computerized measurements and all iPhone measurements, and the difference between the first and second iPhone measurements for each observer were calculated. Inter- and intraobserver reliability of the smartphone measurement method was also tested. The variability of all measurements was similar for the iPhone and the computer-assisted techniques. The concordance between iPhone and computer-assisted angular measurements was excellent for the HVA, IMA, and DMAA. The maximum mean difference between the two techniques was 1.25 ± 1.02° for HVA, 0.92 ± 0.92° for IMA, and 1.10 ± 0.82° for DMAA. The interobserver reliability was excellent for HVA, IMA, and DMAA. The maximum mean difference between observers was 1.31 ± 0.89° for HVA, 0.90 ± 0.92° for IMA, and 0.78 ± 0.87° for DMAA. The intraobserver reliability was excellent for HVA, IMA, and DMAA. We conclude that the Hallux Angles software for the iPhone can be used for measurement of hallux valgus angles in clinical practice and even for research purposes. It is an accurate and reproducible method.

  4. Comparative study of scarf and extended chevron osteotomies for correction of hallux valgus.

    PubMed

    Vopat, Bryan G; Lareau, Craig R; Johnson, Julie; Reinert, Steven E; DiGiovanni, Christopher W

    2013-12-01

    Scarf and chevron osteotomies are two described treatments for the correction of hallux valgus deformity, but they have traditionally been employed for different levels of severity. We hypothesized that there would be no statistically significant difference between the results of these two treatments. This study is a retrospective review of 70 consecutive patients treated operatively for moderate and severe hallux valgus malalignment. The two groups based on their operative treatment: scarf osteotomy (Group A) and extended chevron osteotomy (Group B). Preoperative and postoperative hallux valgus angle (HVA), intermetatarsal angle and distal metatarsal articular angle (DMAA) were measured at final follow-up. Charts were also assessed to determine the postoperative rate of satisfaction, stiffness, and pain. There were no statistically significant differences between Groups A and B with regard to the HVA preoperatively and postoperatively. The DMAA was statistically significantly higher for Group B both preoperatively (p=0.0403) and postoperatively (p<0.0001). The differences in HVA correction and IMA correction were not statistically significant. There were no statistically significant differences with regard to post-operative stiffness, pain, and satisfaction. The scarf and extended chevron osteotomies are capable of adequately reducing the HVA and IMA in patients with moderate to severe hallux valgus. These two techniques yielded similar patient outcomes in terms of stiffness, pain and satisfaction. Based on these results, we recommend both the scarf and extended chevron osteotomy as acceptable forms of correction for moderate to severe hallux valgus.

  5. Scarf versus chevron osteotomy in hallux valgus: a randomized controlled trial in 96 patients.

    PubMed

    Deenik, A R; Pilot, P; Brandt, S E; van Mameren, H; Geesink, R G T; Draijer, W F

    2007-05-01

    The degree of correction of hallux valgus deformity using a distal chevron osteotomy is reported as limited. The scarf osteotomy is reported to correct large intermetatarsal angles (IMA). The purpose of this study was to evaluate if one technique gave greater correction of the IMA and hallux valgus angle (HVA) than the other. After informed consent, 96 feet in 83 patients were randomized into two treatment groups (49 scarf and 47 chevron osteotomies). The results were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) Hallux Valgus Scale and radiographic HVA and IMA measurements. At 27 (range 23-31) months followup both groups improved. The AOFAS score in the chevron group improved from 48 to 89 points and in the scarf group from 47 to 91 points. In the chevron group the HVA corrected from 30 to 17 degrees, and in the scarf group the HVA corrected from 29 to 18 degrees. In both groups, the IMA was corrected from 13 to 10 degrees. The differences were not statistically significant. Three patients in the chevron group developed a partial metatarsal head necrosis. In the scarf group, four patients developed grade 1 complex regional pain syndrome compared to one patient in the chevron group. No differences of statistical significance could be measured between the two groups with respect to the AOFAS score, HVA, and IMA. Although both groups showed good to excellent results, we favor the chevron osteotomy because the procedure is technically less demanding.

  6. Radiographic Shape of Foot With Second Metatarsophalangeal Joint Dislocation Associated With Hallux Valgus.

    PubMed

    Kokubo, Tetsuro; Hashimoto, Takeshi; Suda, Yasunori; Waseda, Akeo; Ikezawa, Hiroko

    2017-12-01

    Second metatarsophalangeal (MTP) joint dislocation is associated with hallux valgus, and the treatment of complete dislocation can be difficult. The purpose of this study was to radiographically clarify the characteristic foot shape in the presence of second MTP joint dislocation. Weight-bearing foot radiographs of the 268 patients (358 feet) with hallux valgus were examined. They were divided into 2 groups: those with second MTP joint dislocation (study group = 179 feet) and those without dislocation (control group = 179 feet). Parameters measured included the hallux valgus angle (HVA), first-second intermetatarsal angle (IMA), second MTP joint angle, hallux interphalangeal angle (IPA), second metatarsal protrusion distance (MPD), metatarsus adductus angle (MAA), and the second metatarsal declination angle (2MDA). Furthermore, the dislocation group was divided into 3 subgroups according to second toe deviation direction: group M (medial type), group N (neutral type), and group L (lateral type). The IPA and the 2MDA were significantly greater in the study group than in the control group. By multiple comparison analysis, the IMA was greatest in group M and smallest in group L. The IPA was smaller and 2MDA greater in group N than in group L. The HVA and MAA in group L were greatest, and MPD in group L was smallest. The patients with second MTP joint dislocation associated with hallux valgus had greater hallux interphalangeal joint varus and a second metatarsal more inclined than with hallux valgus alone. The second toe deviated in a different direction according to the foot shape. Level III, retrospective comparative study.

  7. The hallux valgus angle of the margo medialis pedis as an alternative to the measurement of the metatarsophalangeal hallux valgus angle.

    PubMed

    Klein, Christian; Kinz, Wieland; Zembsch, Alexander; Groll-Knapp, Elisabeth; Kundi, Michael

    2014-04-21

    Currently, the metatarsophalangeal angle (hallux valgus angle) is measured based on radiographic images. However, using X-ray examinations for epidemiological or screening purposes would be unethical, especially in children. For this reason it is discussed to measure the hallux valgus angle of the margo medialis pedis (medial border of the foot) documented on foot outline drawings or foot scans. As a first step on the way to prove the validity of those approaches this study assesses the hallux valgus angle measured on the margo medialis pedis based on the same x-ray pictures as the metatarsophalangeal hallux valgus. Radiographic images of the foot were obtained from patients with symptomatic hallux valgus malformation. Twelve sets of contact copies of the 63 originals were made, and were marked and measured according to three different methods, each one performed by two observers and with two repeated measurements. Thus, data sets from 756 individual assessments were entered into the multifactorial statistical analysis.Comparisons were made between the angle of the margo medialis pedis and the metatarsophalangeal angle, which was determined by two different methods. To determine the inter- and intraobserver reliability of the different methods, each assessment was conducted by two independent experts and repeated after a period of several weeks. The correlations between the hallux valgus angles determined by the three different methods were all above r=0.89 (p<0.001) and thus highly significant. The values obtained by measuring the margo medialis pedis angle, however, were on average 4.8 degrees smaller than the metatarsophalangeal angles. No significant differences were found between the observers. No systematic deviations for any observer between repeated measurements were detected. Measurements of the radiographic hallux angle of the margo medialis pedis are reliable and show high correlation with the metatarsophalangeal angle. Because the hallux valgus angles

  8. The hallux valgus angle of the margo medialis pedis as an alternative to the measurement of the metatarsophalangeal hallux valgus angle

    PubMed Central

    2014-01-01

    Background Currently, the metatarsophalangeal angle (hallux valgus angle) is measured based on radiographic images. However, using X-ray examinations for epidemiological or screening purposes would be unethical, especially in children. For this reason it is discussed to measure the hallux valgus angle of the margo medialis pedis (medial border of the foot) documented on foot outline drawings or foot scans. As a first step on the way to prove the validity of those approaches this study assesses the hallux valgus angle measured on the margo medialis pedis based on the same x-ray pictures as the metatarsophalangeal hallux valgus. Methods Radiographic images of the foot were obtained from patients with symptomatic hallux valgus malformation. Twelve sets of contact copies of the 63 originals were made, and were marked and measured according to three different methods, each one performed by two observers and with two repeated measurements. Thus, data sets from 756 individual assessments were entered into the multifactorial statistical analysis. Comparisons were made between the angle of the margo medialis pedis and the metatarsophalangeal angle, which was determined by two different methods. To determine the inter- and intraobserver reliability of the different methods, each assessment was conducted by two independent experts and repeated after a period of several weeks. Results The correlations between the hallux valgus angles determined by the three different methods were all above r = 0.89 (p < 0.001) and thus highly significant. The values obtained by measuring the margo medialis pedis angle, however, were on average 4.8 degrees smaller than the metatarsophalangeal angles. No significant differences were found between the observers. No systematic deviations for any observer between repeated measurements were detected. Conclusions Measurements of the radiographic hallux angle of the margo medialis pedis are reliable and show high correlation with the

  9. A geometric analysis of hallux valgus: correlation with clinical assessment of severity

    PubMed Central

    Piqué-Vidal, Carlos; Vila, Joan

    2009-01-01

    Background Application of plane geometry to the study of bunion deformity may represent an interesting and novel approach in the research field of hallux valgus. For the purpose of contributing to development of a different perspective in the assessment of hallux valgus, this study was conducted with three objectives: a) to determine the position on the intersection point of the perpendicular bisectors of the longitudinal axes of the first metatarsal and proximal phalanx (IP), b) to correlate the location of this point with hallux valgus deformity according to angular measurements and according to visual assessment of the severity carried out by three independent observers, and c) to assess whether this IP correlated with the radius of the first metatarsophalangeal arc circumference. Methods Measurements evaluated were intermetatarsal angle (IMA), hallux valgus angle (HVA), and proximal phalangeal articular angle (PPAA). The Autocad® program computed the location of the IP inside or outside of the foot. Three independent observers rated the severity of hallux valgus in photographs using a 100-mm visual analogue scale (VAS). Results Measurements of all angles except PPAA showed significantly lower values when the IP was located out of the foot more distantly and vice versa, significantly higher values for severe deformities in which the IP was found inside the foot (p < 0.001). The IP correlated significantly with VAS scores and with the length of the radius of the circle that included the first metatarsophalangeal arc circumference (p < 0.001) Conclusion The IP is a useful indicator of hallux valgus deformity because correlated significantly with IMA and HVA measurements, VAS scores obtained by visual inspection of the degree of deformity, and location of the center of the first metatarsophalangeal arc circumference. PMID:19442286

  10. Increased Incidence and Severity of Postoperative Radiographic Hallux Valgus Interphalangeus With Surgical Correction of Hallux Valgus.

    PubMed

    Dixon, Alexis E; Lee, Lydia C; Charlton, Timothy P; Thordarson, David B

    2015-08-01

    A previous study has shown an increased radiographic prevalence and severity of hallux valgus interphalangeus (HVIP) after surgical correction of hallux valgus (HV) due to correction of pronation deformity. The purpose of this study was to evaluate the change in pre- and postoperative HVIP deformity with correction of HV with multiple radiographic parameters. A retrospective chart review identified all bunion surgeries performed at a single center from July 1, 2009, to September 30, 2012. Exclusion criteria included prior bony surgery to the first ray, inadequate films, nonadult bunion, Akin osteotomy, or surgical treatment other than bunion correction. Pre- and postoperative films were reviewed for 2 HV angular measurements and 5 HVIP measurements, which were compared. The angles measured were hallux valgus angle (HVA), first intermetatarsal angle (IMA), hallux interphalangeus angle (HIA), distal metatarsal articular angle (DMAA), proximal phalangeal articular angle (PPAA), proximal to distal phalangeal articular angle (PDPAA), and total distal deformity (TDD). Prevalence of HVIP was analyzed in pre- and postoperative radiographs. A 1-sided Student t test was used to compare continuous data, and a chi-square test was used to compare categorical data. Ninety-two feet in 82 patients were eligible. The average preoperative HV improved with surgery. Preoperative HVA improved from 27 to 11 degrees (P < .001). Preoperative IMA improved from 13.6 to 6.1 degrees (P < .001). HVIP worsened after surgery. Preoperative HIA increased from 7.2 to 13.2 degrees (P < .001). DMAA worsened from 7.3 to 9.2 degrees (P = .001). PPAA worsened from 3.2 to 6.2 degrees. PDPAA worsened from 6.7 to 8.2 degrees (P < .001). The TDD increased from 14.6 to 17.9 degrees (P < .001). The prevalence of HVIP pre- and postoperatively as defined by HIA increased from 26% to 79% (P < .001) and by PPAA from 12% to 46% (P < .001). Initial assessment of preoperative radiographs underestimated HVIP

  11. Chevron osteotomy with lateral release and adductor tenotomy for hallux valgus.

    PubMed

    Potenza, Vito; Caterini, Roberto; Farsetti, Pasquale; Forconi, Fabrizio; Savarese, Eugenio; Nicoletti, Simone; Ippolito, Ernesto

    2009-06-01

    Distal chevron osteotomy is a procedure widely performed for the surgical treatment of painful hallux valgus. The risks and benefits of a lateral capsular release and adductor tenotomy combined with chevron osteotomy are still debated. The aim of our study was to report the clinical and radiographic outcomes of this combined procedure in mild and moderate incongruent bunion deformities, with a hallux valgus angle (HVA) up to 40 degrees and an intermetatarsal angle (IMA) up to 20 degrees. Forty-two patients (52 feet) who consecutively underwent chevron osteotomy combined with lateral release and adductor tenotomy were reviewed 24-36 months after surgery. The mean age of the patients was 53.5 (range, 43 to 64) years. All the deformities were mild to moderate, with a mean preoperative value of 28 degrees in the HVA (range, 16 degrees to 40 degrees) and of 13 degrees in the IMA (range, 9 degrees to 20 degrees). At followup, the AOFAS hallux score improved from an average of 46 to an average of 88. The HVA and IMA had an average postoperative decrease respectively of 12 degrees and 6 degrees; lateral sesamoid displacement decreased by a mean of 15%. In no case did we observe infection or nonunion of the osteotomy. In one case, painless avascular necrosis of the first metatarsal head developed. Our short-term results show that distal chevron osteotomy combined with lateral release and adductor tenotomy is a feasible surgical option to address mild to moderate hallux valgus deformity, even with an IM angle between 15 and 20 degrees. Clinical and radiographic outcomes are generally good and patient satisfaction is generally high.

  12. Point-Connecting Measurements of the Hallux Valgus Deformity: A New Measurement and Its Clinical Application

    PubMed Central

    Seo, Jeong-Ho; Boedijono, Dimas

    2016-01-01

    Purpose The aim of this study was to investigate new point-connecting measurements for the hallux valgus angle (HVA) and the first intermetatarsal angle (IMA), which can reflect the degree of subluxation of the first metatarsophalangeal joint (MTPJ). Also, this study attempted to compare the validity of midline measurements and the new point-connecting measurements for the determination of HVA and IMA values. Materials and Methods Sixty feet of hallux valgus patients who underwent surgery between 2007 and 2011 were classified in terms of the severity of HVA, congruency of the first MTPJ, and type of chevron metatarsal osteotomy. On weight-bearing dorsal-plantar radiographs, HVA and IMA values were measured and compared preoperatively and postoperatively using both the conventional and new methods. Results Compared with midline measurements, point-connecting measurements showed higher inter- and intra-observer reliability for preoperative HVA/IMA and similar or higher inter- and intra-observer reliability for postoperative HVA/IMA. Patients who underwent distal chevron metatarsal osteotomy (DCMO) had higher intraclass correlation coefficient for inter- and intra-observer reliability for pre- and post-operative HVA and IMA measured by the point-connecting method compared with the midline method. All differences in the preoperative HVAs and IMAs determined by both the midline method and point-connecting methods were significant between the deviated group and subluxated groups (p=0.001). Conclusion The point-connecting method for measuring HVA and IMA in the subluxated first MTPJ may better reflect the severity of a HV deformity with higher reliability than the midline method, and is more useful in patients with DCMO than in patients with proximal chevron metatarsal osteotomy. PMID:26996576

  13. [The retrocapital osteotomy ("chevron") for correction of splayfoot with hallux valgus].

    PubMed

    Gabel, Michael

    2008-12-01

    Surgical treatment of hallux valgus deformity with a distal osteotomy of the first metatarsal to address an increased intermetatarsal angle (IMA) I-II. This procedure is combined with a soft-tissue procedure at the first metatarsophalangeal joint: realignment of the first ray, lateral displacement of the first metatarsal head above the sesamoids, rebalancing of the soft tissues at the metatarsophalangeal joint. Pain and soft-tissue inflammation at the bunion, impaired function of the metatarsophalangeal joint, and lateral deviation of the hallux. IMA I-II valgus angle (HVA) angle (DMAA) > 10 degrees. Symptomatic osteoarthritis of the first metatarsophalangeal joint, assessed clinically or radiographically. Acute inflammation of the forefoot, osteoporosis of the first metatarsal. Vascular disturbance. Cosmetic indication only. Relative: hypermobility of the first ray, valgus malalignment of the hindfoot, previous retrocapital osteotomy. Lateral soft-tissue release. Resection of the medial pseudoexostosis. V-shaped osteotomy of the distal metatarsal I. Exostosectomy. Lateral displacement of the first metatarsal head. Screw fixation. Realignment of the metatarsophalangeal joint by tightening of the medial soft tissues. Postoperative shoe with full weight bearing. Active exercises of the foot and hallux. Physiotherapy. Prophylaxis of deep vein thrombosis depending on the degree of mobility. Radiographic control after 6 weeks. Bandage or orthosis to maintain toe alignment. IMA I-II was reduced from 13.6 degrees preoperatively to 6.6 degrees postoperatively. HVA decreased from 29.8 degrees to 8.2 degrees postoperatively.

  14. Reliability of Two Smartphone Applications for Radiographic Measurements of Hallux Valgus Angles.

    PubMed

    Mattos E Dinato, Mauro Cesar; Freitas, Marcio de Faria; Milano, Cristiano; Valloto, Elcio; Ninomiya, André Felipe; Pagnano, Rodrigo Gonçalves

    The objective of the present study was to assess the reliability of 2 smartphone applications compared with the traditional goniometer technique for measurement of radiographic angles in hallux valgus and the time required for analysis with the different methods. The radiographs of 31 patients (52 feet) with a diagnosis of hallux valgus were analyzed. Four observers, 2 with >10 years' experience in foot and ankle surgery and 2 in-training surgeons, measured the hallux valgus angle and intermetatarsal angle using a manual goniometer technique and 2 smartphone applications (Hallux Angles and iPinPoint). The interobserver and intermethod reliability were estimated using intraclass correlation coefficients (ICCs), and the time required for measurement of the angles among the 3 methods was compared using the Friedman test. A very good or good interobserver reliability was found among the 4 observers measuring the hallux valgus angle and intermetatarsal angle using the goniometer (ICC 0.913 and 0.821, respectively) and iPinPoint (ICC 0.866 and 0.638, respectively). Using the Hallux Angles application, a very good interobserver reliability was found for measurements of the hallux valgus angle (ICC 0.962) and intermetatarsal angle (ICC 0.935) only among the more experienced observers. The time required for the measurements was significantly shorter for the measurements using both smartphone applications compared with the goniometer method. One smartphone application (iPinPoint) was reliable for measurements of the hallux valgus angles by either experienced or nonexperienced observers. The use of these tools might save time in the evaluation of radiographic angles in the hallux valgus. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  15. Preoperative radiological factors correlated to long-term recurrence of hallux valgus following distal chevron osteotomy.

    PubMed

    Pentikainen, Ilkka; Ojala, Risto; Ohtonen, Pasi; Piippo, Jouni; Leppilahti, Juhana

    2014-12-01

    The purpose of this article was to analyze the long-term radiologic results after distal chevron osteotomy for hallux valgus treatment and to determine the preoperative radiographic factors correlating with radiological recurrence of the deformity. The study included 100 consecutive patients who received distal chevron osteotomy for hallux valgus. The osteotomy included fixation with an absorbable pin in 50 cases, and no fixation in the other 50. For 6 weeks postoperatively, half of each group used a soft cast and half had a traditional elastic bandage. Weight-bearing radiographs were evaluated at 6 weeks, 6 months, 1 year, and a mean of 7.9 (range, 5.8-9.4) years postoperatively. At the final follow-up, radiological recurrence of hallux valgus deformity (HVA > 15 degrees) was observed in 56 feet (73%). Eleven feet (14%) had mild recurrence (HVA < 20 degrees), 44 (57%) moderate (20 degrees ≥ HVA < 40 degrees), and 1 (1%) severe (HVA ≥ 40 degrees). All recurrences were painless, and thus no revision surgery was required. Long-term hallux valgus recurrence was significantly affected by preoperative congruence, DMAA, sesamoid position, HVA, and I/II IMA. Radiological recurrence of hallux valgus deformity of 15 degrees or more was very common at long-term follow-up after distal chevron osteotomy. Preoperative congruence, DMAA, sesamoid position (LaPorta), HVA, and I/II IMA significantly affected recurrence. Level III, comparative case series. © The Author(s) 2014.

  16. A Prospective Study of Distal Metatarsal Chevron Osteotomies with K-Wire Fixations to Treat Hallux Valgus Deformities.

    PubMed

    Baig, M N; Baig, Usman; Tariq, Ali; Din, Robert

    2017-09-20

    Introduction Hallux valgus is one of the most common forefoot deformities worldwide. Females are affected more often than males. The three most common clinical symptoms are the painful bunion, transfer metatarsalgia, and hammer or claw toes. Methods This case series consisted of 20 patients who had chevron osteotomy from January 2015 to January 2016. The clinical assessment was measured by The American Orthopedic Foot and Ankle Score (AOFAS), and radiologic assessment was determined by preoperative and postoperative hallux valgus angle (HVA) and intermetatarsal angle (IMA). Results The patients' mean age was 56 years. Out of 20 patients, 19 were female, and one was male. The mean AOFAS improved from 51 preoperatively to 82 postoperatively. The HVA improved from 26° preoperatively to 14°. There were five complications including four Kirschner (K)-wire complications. Conclusion Distal chevron osteotomy is a reliable and time-tested procedure. The K-wire fixation has a relatively high complication rate. We planned to use other methods of fixation and then compared them with K-wires fixation results for future studies.

  17. A Prospective Study of Distal Metatarsal Chevron Osteotomies with K-Wire Fixations to Treat Hallux Valgus Deformities

    PubMed Central

    Baig, Usman; Tariq, Ali; Din, Robert

    2017-01-01

    Introduction Hallux valgus is one of the most common forefoot deformities worldwide. Females are affected more often than males. The three most common clinical symptoms are the painful bunion, transfer metatarsalgia, and hammer or claw toes. Methods This case series consisted of 20 patients who had chevron osteotomy from January 2015 to January 2016. The clinical assessment was measured by The American Orthopedic Foot and Ankle Score (AOFAS), and radiologic assessment was determined by preoperative and postoperative hallux valgus angle (HVA) and intermetatarsal angle (IMA). Results The patients’ mean age was 56 years. Out of 20 patients, 19 were female, and one was male. The mean AOFAS improved from 51 preoperatively to 82 postoperatively. The HVA improved from 26° preoperatively to 14°. There were five complications including four Kirschner (K)-wire complications. Conclusion Distal chevron osteotomy is a reliable and time-tested procedure. The K-wire fixation has a relatively high complication rate. We planned to use other methods of fixation and then compared them with K-wires fixation results for future studies. PMID:29167752

  18. Hallux Valgus Correction Comparing Percutaneous Chevron/Akin (PECA) and Open Scarf/Akin Osteotomies.

    PubMed

    Lee, Moses; Walsh, James; Smith, Margaret M; Ling, Jeff; Wines, Andrew; Lam, Peter

    2017-08-01

    Minimally invasive surgery is being used increasingly, including for hallux valgus surgery. Despite the growing interest in minimally invasive procedures, there have been few publications on percutaneous chevron/akin (PECA) procedures, and no studies have been published comparing PECA to open scarf/akin osteotomies (SA). This was a prospective, randomized study of 50 patients undergoing operative correction of hallux valgus using one of 2 techniques (PECA vs open SA). Data were collected preoperatively and on 1 day, 2 weeks, 6 weeks, and 6 months postoperatively. Outcome measures include the American Orthopaedic Foot & Ankle Society Hallux-Metatarsophalangeal-Interphalangeal (AOFAS-HMI) Score, visual analog pain score, hallux valgus angle (HVA), and 1-2 intermetatarsal angle (IMA). Twenty-five patients underwent PECA procedures and 25 patients received SA procedures. Both groups showed significantly improved AOFAS-HMI scores after surgery (PECA group: 61.8 to 88.9, SA group: 57.3 to 84.1, P = .560) with comparable final scores. HVA and IMA also presented similar outcomes at final follow-up ( P = .520 and P = .270, respectively). However, the PECA group showed significantly lower pain level (VAS) in the early postoperative phase (postoperative day 1 to postoperative week 6, P < .001 and P = .004, respectively). No serious complications were observed in either group. Both groups showed comparable good to excellent clinical and radiologic outcomes at final follow-up. However, the PECA group had significantly less pain in the first 6 weeks following surgery. Level of Evidence Level II, prospective comparative study.

  19. Equivalent correction in scarf and chevron osteotomy in moderate and severe hallux valgus: a randomized controlled trial.

    PubMed

    Deenik, Axel; van Mameren, Henk; de Visser, Enrico; de Waal Malefijt, Maarten; Draijer, Frits; de Bie, Rob

    2008-12-01

    Chevron osteotomy is a widely accepted osteotomy for correction of hallux valgus.(18) Algorithms were developed to overcome the limitations of distal osteotomies. Scarf osteotomy has become popular as a versatile procedure that should be able to correct most cases of acquired hallux valgus. The purpose of this study was to evaluate whether patients with moderate or severe hallux valgus have better correction with a scarf osteotomy as compared to chevron osteotomy. After informed consent, 136 feet in 115 patients were randomized to 66 scarf and 70 chevron osteotomies. Deformities of patients were classified as mild, moderate and severe according to IMA, and both groups were compared with independent t-tests. The results were measured using radiographic HVA, IMA and DMAA measurements. There were no statistical differences in HVA, IMA and DMAA between scarf and chevron osteotomy in mild to moderate hallux valgus. In severe hallux valgus, chevron osteotomy corrected HVA better than scarf osteotomy, although this group consisted of twelve patients only. Five patients in the chevron group and seven in the scarf group developed recurrent subluxation of the metatarsophalangeal joint. In patients with moderate and severe hallux valgus, the results of chevron osteotomy were at least as effective as a scarf osteotomy. Recurrent subluxation of the first metatatarsophalangeal joint was the main cause for insufficient correction. We favor the chevron osteotomy because it is less invasive, without sacrificing correction of HVA and IMA.

  20. Comparison of distal chevron osteotomy with and without lateral soft tissue release for the treatment of hallux valgus.

    PubMed

    Lee, Ho-Jin; Chung, Jin-Wha; Chu, In-Tak; Kim, Yoon-Chung

    2010-04-01

    A lateral soft tissue release is often performed with distal chevron osteotomy for the correction of hallux valgus deformities. However, many complications of lateral soft tissue release have been reported. To define the necessity of lateral soft tissue release, the authors compared the clinical and radiographic results of distal chevron osteotomy with and without it. 86 consecutive patients (152 feet) were enrolled in this prospective study. In Group A, 45 patients (74 feet) underwent a chevron osteotomy with lateral soft tissue release. In Group B, 41 patients (78 feet) underwent a chevron osteotomy without it. Mean followup was 1.7 years and 2.1 years, respectively. The hallux valgus angle (HVA) and intermetatarsal angle (IMA), and AOFAS score were measured preoperatively, and 1-year followup postoperatively and complications were evaluated. The change in HVA, IMA and AOFAS score were insignificant (p > 0.05) between Group A and Group B, however, the range of motion of the first metatarsophalangeal joint was significantly less in Group A (p < 0.05). Complications of digital neuritis and cosmetically dissatisfied scarring of the dorsal web space were seen only in Group A. No cases had avascular necrosis of the metatarsal head, malunion or nonunion. Lateral soft tissue release may not be needed for mild or moderate hallux valgus deformities which may prevent decreased range of motion of the first metatarsophalangeal joint, neuritis of dorsal or plantar lateral digital nerve and cosmetic dissatisfaction of a dorsal scar.

  1. The correlation between calcaneal valgus angle and asymmetrical thoracic-lumbar rotation angles in patients with adolescent scoliosis.

    PubMed

    Park, Jaeyong; Lee, Sang Gil; Bae, Jongjin; Lee, Jung Chul

    2015-12-01

    [Purpose] This study aimed to provide a predictable evaluation method for the progression of scoliosis in adolescents based on quick and reliable measurements using the naked eye, such as the calcaneal valgus angle of the foot, which can be performed at public facilities such as schools. [Subjects and Methods] Idiopathic scoliosis patients with a Cobb's angle of 10° or more (96 females, 22 males) were included in this study. To identify relationships between factors, Pearson's product-moment correlation coefficient was computed. The degree of scoliosis was set as a dependent variable to predict thoracic and lumbar scoliosis using ankle angle and physique factors. Height, weight, and left and right calcaneal valgus angles were set as independent variables; thereafter, multiple regression analysis was performed. This study extracted variables at a significance level (α) of 0.05 by applying a stepwise method, and calculated a regression equation. [Results] Negative correlation (R=-0.266) was shown between lumbar lordosis and asymmetrical lumbar rotation angles. A correlation (R=0.281) was also demonstrated between left calcaneal valgus angles and asymmetrical thoracic rotation angles. [Conclusion] Prediction of scoliosis progress was revealed to be possible through ocular inspection of the calcaneus and Adams forward bending test and the use of a scoliometer.

  2. Accuracy of estimating Unicondylar Knee Replacement implant varus/valgus angles from antero-posterior radiographs.

    PubMed

    Khare, Rahul; Jaramaz, Branislav

    2016-12-01

    Unicondylar Knee Replacement (UKR) is an orthopedic surgical procedure to reduce pain and improve function in the knee. Load-bearing long-standing antero-posterior (AP) radiographs are typically used postoperatively to measure the leg alignment and assess the varus/valgus implant orientation. However, implant out-of-plane rotations, user variability, and X-ray acquisition parameters introduce errors in the estimation of the implant varus/valgus estimation. Previous work has explored the accuracy of various imaging modalities in this estimation. In this work, we explored the impact of out-of-plane rotations and X-ray acquisition parameters on the estimation of implant component varus/valgus angles. For our study, we used a single CT scan and positioned femoral and tibial implants under varying orientations within the CT volume. Then, a custom software application was used to obtain digitally reconstructed radiographs from the CT scan with implants under varying orientations. Two users were then asked to manually estimate the varus/valgus angles for the implants. We found that there was significant inter-user variability (p < 0.05) in the varus/valgus estimates for the two users. However, the 'ideal' measurements, obtained using actual implant orientations, showed small errors due to variations in implant orientation. We also found that variation in the projection center does not have a statistically significant impact (p < 0.01) on the estimation of implant varus/valgus angles. We conclude that manual estimates of UKR implant varus/valgus orientations are unreliable.

  3. [Clinical effect modified Chevron osteotomy combined with lateral tissue loosening in treating mild-moderate hallux valgus through internal signal approach].

    PubMed

    Chen, Xue-Qiang; Wu, Qun-Feng; Dong, Wei-Qin; Yu, Li-Xin; Li, Xiong-Feng

    2018-03-25

    To explore clinical effect of modified Chevron osteotomy combined with lateral tissue loosening for the treatment of mild-moderate hallux valgus through internal signal approach. From July 2015 to June 2016, 26 patients with mild-moderate hallux valgus treated with modified Chevron osteotomy combined with lateral tissue loosening through internal signal approach, including 2 males and 24 females aged from 45 to 65 years old with an average of(54.6±4.8) years old;the courses of diseases ranged from 1 to 5 months with an average of (7.5±3.3) months. Hallux valgus angle(HVA), inter metatarsal angle(IMA) were measured at 12 months after operation, and AOFAS score was applied to evaluate clinical effect before and after operation. All incisions were healed at stage I. No incision occurred infection, metatarsal necrosis and recurrence of hallux valgus deformity. Two patients occurred skin numbness caused by musculocutaneous nerve injury. Twenty-six patients were followed up from 6 to 12 months with an average of(9.12±2.06) months. HVA, IMA were(30.01±3.71)°, (14.00±1.50)° before operation and(9.41±4.16)°, (7.00±0.60)° after operation, which had significant difference. There was statistical significance in AOFAS score before operation 54.77±9.59 and after operation 92.73±5.47, and 19 cases obtained excellent results and 7 moderate. Modified Chevron osteotomy combined with full thread headless pressure screw fixation and lateral tissue loosening for the treatment of mild-moderate hallux valgus has advantages of excellent exposure, simple operation, stable fixation, rapid recovery. Akin osteotomy with internal capsulorrhaphy were used with lateral loosening and could recover soft tissue balance between lateral and internal, and could receive satisfied clinical effects. Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.

  4. Proximal reverse chevron metatarsal osteotomy, lateral soft tissue release, and akin osteotomy through a single medial incision for hallux valgus.

    PubMed

    Jung, Hong-Geun; Kim, Tae-Hoon; Park, Jong-Tae; Shin, Min-Ho; Lee, Sang-Hun

    2014-04-01

    Scarring on the dorsal first web space after lateral soft tissue release can be a major contributor to patient dissatisfaction following hallux valgus surgery. We hypothesized that performing distal soft tissue procedure (DSTP), proximal reverse chevron metatarsal osteotomy (PCMO), and Akin osteotomy through a single medial incision would provide better clinical and radiographic results with improved patient satisfaction compared with bunion corrections performed through 2 incisions. The study included 117 feet (of 98 patients) with moderate to severe hallux valgus. Clinically, the preoperative and final follow-up visual analog scale (VAS) pain scores, the preoperative and final follow-up American Orthopaedic Foot & Ankle Society (AOFAS) hallux metatarsophalangeal (MTP)-interphalangeal (IP) scores, first MTP joint range of motion (ROM), and patient satisfaction after the surgery were evaluated. Radiographically, the hallux valgus angle (HVA), intermetatarsal angle (IMA), hallux valgus interphalangeal angle (HIA), medial sesamoid position (MSP), and first to fifth metatarsal width (1-5MTW) were analyzed before and after surgery. The mean AOFAS hallux score improved from 56.3 preoperatively to 90.6 at the final follow-up, and the mean VAS pain score decreased from 6.8 preoperatively to 1.5 at the final follow-up (P < .001). Ninety-five percent of the patients were satisfied with the surgery. Radiographically, the mean HVA decreased from 36.1 degrees (range, 16.0 to 44.0 degrees) preoperatively to 5.4 degrees (range, -12.4 to 29.7 degrees) at the final follow-up (P < .001), and the mean IMA decreased from 19.0 degrees (range, 9.0 to 28.0 degrees) preoperatively to 4.5 degrees (range, -5.0 to 14.2 degrees) at the final follow-up (P < .001). The mean 1-5MTW also decreased by 16% (16 mm) from 97.3 mm (range, 85.0 to 110.0 mm) preoperatively to 81.3 mm (range, 70.0 to 95.0 mm) at the final follow-up (P < .001). We achieved very favorable clinical and radiographic outcomes

  5. Clinical and Radiological Outcomes Comparing Percutaneous Chevron-Akin Osteotomies vs Open Scarf-Akin Osteotomies for Hallux Valgus.

    PubMed

    Lai, Mun Chun; Rikhraj, Inderjeet Singh; Woo, Yew Lok; Yeo, William; Ng, Yung Chuan Sean; Koo, Kevin

    2018-03-01

    Minimally invasive surgeries have gained popularity due to less soft tissue trauma and better wound healing. To date, limited studies have compared the outcomes of percutaneous and open osteotomies. This study aims to investigate the clinical and radiological outcomes of percutaneous chevron-Akin osteotomies vs open scarf-Akin osteotomies at 24-month follow-up. We reviewed a prospectively collected database in a tertiary hospital hallux valgus registry. Twenty-nine feet that underwent a percutaneous technique were matched to 58 feet that underwent open scarf and Akin osteotomies. Clinical outcome measures assessed included visual analog scale (VAS) scores, American Orthopaedic Foot & Ankle Society Hallux Metatarsophalangeal-Interphalangeal score (AOFAS Hallux MTP-IP), and Short Form 36 (SF-36) Health Survey. Radiological outcomes included hallux valgus angle (HVA) and intermetatarsal angle (IMA). All patients were prospectively followed up at 6 and 24 months. Both groups showed comparable clinical and radiological outcomes at the 24-month follow-up. However, the percutaneous group demonstrated less pain in the perioperative period ( P < .001). There were significant differences in the change in HVA between the groups but comparable radiological outcomes in IMA at the 24-month follow-up. The percutaneous group demonstrated shorter length of operation ( P < .001). There were no complications in the percutaneous group but 3 wound complications in the open group. We conclude that clinical and radiological outcomes of third-generation percutaneous chevron-Akin osteotomies were comparable with open scarf and Akin osteotomies at 24 months but with significantly less perioperative pain, shorter length of operation, and less risk of wound complications. Level III, retrospective comparative series.

  6. Is Double Metatarsal Osteotomy Superior to Proximal Chevron Osteotomy in Treatment of Hallux Valgus With Increased Distal Metatarsal Articular Angle?

    PubMed

    Park, Chul Hyun; Lee, Woo-Chun

    We compared the results of proximal chevron osteotomy and double metatarsal osteotomy for hallux valgus with an increased distal metatarsal articular angle (DMAA). From October 2008 to December 2012, first metatarsal osteotomies were performed in 64 patients (69 feet) with symptomatic hallux valgus associated with an increased DMAA. Proximal chevron with Akin osteotomy and lateral soft tissue release was performed in 46 feet (PCO group); double metatarsal osteotomy and Akin osteotomy without lateral soft tissue release was performed in 23 feet (DMO group). Clinical assessments were performed using the American Orthopaedic Foot and Ankle Society (AOFAS) scale and visual analog scale (VAS). The hallux valgus angles, intermetatarsal angles, sesamoid positions, metatarsus adductus angles, and DMAAs were compared at different postoperative times. Postoperative shortening of first the metatarsal and complications were compared. The mean AOFAS scale and VAS scores showed significant improvement in both groups after surgery; however, no significant difference was observed between the 2 groups. The immediate postoperative hallux valgus angle and sesamoid position were significantly larger in DMO group; however, no intergroup difference was observed at the last follow-up visit, with the hallux valgus angle gradually increasing in the PCO group. The postoperative DMAA was significantly smaller in the DMO group. The mean shortening of the first metatarsal after surgery was significantly larger in the DMO group than in the PCO group. Transfer metatarsalgia developed in 1 foot (2.2%) in the PCO group and 2 feet (8.7%) in the DMO group. Partial avascular necrosis of the metatarsal head with advanced arthritis of the first metatarsophalangeal joint developed in 1 foot (4.3%) in the DMO group. In conclusion, no differences in the clinical and radiographic results were observed between the 2 groups for hallux valgus deformity with an increased DMAA. Copyright © 2017 The American

  7. Measurement of first ray of foot with reference to hallux valgus.

    PubMed

    Howale, Deepak S; Iyer, Kanaklata V; Shah, Jigesh V

    2012-06-01

    A study was carried out on 58 healthy volunteers. None of the volunteeres had any foot complaints. This was done to study Indian feet, as foot is an important part of human anatomy and its certain deformities eg, hallux valgus, can be very disabling. We have studied anatomical angles between 1st and 2nd rays of foot eg, angle of hallux valgus and angle of slant of distal facet of medial cuneiform and have shown significant correlation between them and development of hallux valgus. The coefficient of correlation (r) calculated between these two angles is significant, showing that this angle influences the angle of hallux valgus and hence development of hallux valgus. These are anatomical angles and indicate shapes of medial cuneiform and 1st metatarsal. Hence these seem to be inherited, making the feet anatomically predisposed to develop hallux valgus. This view is supported by Gray's Anatomy. The extrinsic factors such as narrow toes, closed, footwear worn for an extended period do increase the angle of hallux valgus. So, in predisposed feet, this is one of the extrinsic factor which can lead to development of hallux valgus. On studying these two angles, orthopaedicians should be on alert and should advise such individuals on wearing foot- friendly foot-wear.

  8. [PERSONALIZED DISTAL FEMORAL VALGUS RESECTION ANGLE IN PRIMARY TOTAL KNEE ARTHROPLASTY].

    PubMed

    Wang, Xilong; Shang, Xifu; Ll, Guoyuan; He, Rui; Zheng, Jie

    2015-01-01

    To investigate the feasibility and effectiveness of a personalized distal femoral valgus resection angle for improving postoperative coronal alignment of lower limb in total knee arthroplasty (TKA). A retrospective analysis was made on the clinical data of 50 patients who received primary TKA between January 2013 and February 2013. There were 11 male and 39 female patients with degenerative knee osteoarthritis. The patients were divided into 2 groups. In test group (n=25), the resection angle was adjusted to the femoral mechanical anatomical angle (FMA); in control group (n=25), a fixed distal valgus resection angle of 5° was used. There was no significant difference in gender, age, body mass index, disease duration, sides, grade, preoperative FMA, mechanical femorotibial angle (MFT), and preoperative Knee Society Score (KSS) between 2 groups (P > 0.05). Whole long X-ray film was taken to measure FMA and MFT at 3 days after operation, postoperative KSS was used to evaluate the knee function after 6 and 15 months. MFT was (-0.20 ± 1.87)° in test group and was (1.71 ± 3.67)° in control group, showing significant difference between 2 groups (t = 2.32, P = 0.02). The ideal MFT angle (0 ± 3)° was achieved in 22 patients (88%) of test group and in 16 patients (64%) of control group, showing significant difference between 2 groups (χ2 = 2.32, P = 0.02). Primary healing of incision was obtained in all patients of 2 groups. No deep venous thrombosis occurred. The patients of 2 groups were followed up 15 months after operation. There was significant difference in KSS between test and control groups at 6 months (88.23 ± 2.57 vs. 82.92 ± 2.59) (t = 7.26, P = 0.00) and at 15 months (90.76 ± 2.77 vs. 88.65 ± 1.77) (t = 3.20, P = 0.02). No sign of prosthesis loosening was observed by X-ray examination. Compared with using of a fixed distal femoral resection angle, an individual FMA can significantly improve the postoperative MFT and promote early recovery of the knee

  9. Proximal metatarsal osteotomy for hallux valgus: an audit of radiologic outcome after single screw fixation and full postoperative weightbearing

    PubMed Central

    2013-01-01

    Background Proximal metatarsal osteotomy combined with a distal soft-tissue procedure is a common treatment for moderate to severe hallux valgus. Secure stabilisation of the metatarsal osteotomy is necessary to avoid complications such as delayed union, nonunion or malunion as well as loss of correction. The aim of this study was to report our results using a single screw for stabilisation of the osteotomy. Methods We retrospectively reviewed 151 patients with severe hallux valgus who were treated by the above mentioned way with full postoperative weightbearing in a stiff soled shoe. Mean age of patients at time of surgery was 54 years, 19 patients were male and 132 female. Assessment of clinical and radiographic results was performed after 2 days and 6 weeks. Results were also correlated to the experience of the performing surgeon. Results Mean preoperative HVA (hallux valgus angle) was 36.4 degrees, and then 3.5 degrees 2 days and 13.4 degrees 6 weeks after the procedure (p < 0.001). Mean preoperative IMA (intermetarsal angle) was 16.8 degrees, and then 6.4 degrees after 2 days and 9.8 degrees after 6 weeks (p < 0.001). Mean preoperative first metatarsal length of 56.4 mm decreased to 53.6 mm after 6 weeks. Possible non-union of the osteotomy was observed in 4 patients (2.6%) after 6 weeks. Performing residents (n = 40) operated in 65 minutes and attending surgeons (n = 111) in 45 minutes, with no significant differences in radiographic measurements between both groups. Conclusions Single screw stabilisation of proximal chevron osteotomy is a reliable method for treating severe hallux valgus deformities with satisfactory results. PMID:23725485

  10. Bone morphotypes of the varus and valgus knee.

    PubMed

    Thienpont, E; Schwab, P E; Cornu, O; Bellemans, J; Victor, J

    2017-03-01

    Coronal deformity correction with total knee arthroplasty (TKA) is an important feature in the treatment of osteoarthritis (OA). The hypothesis of this study was that bone morphology would be different in varus and valgus deformity, both before osteoarthritis development as well as during and after the disease process of OA. Retrospective study with measurements on preoperative and postoperative full leg standing radiographs of 96 patients who underwent TKA. The included patients were selected for this study because they had an OA knee on one side and a non-arthritic knee on the contralateral side presenting the same type of alignment as the to-be-operated knee (varus or valgus alignment on both sides). The control group of 46 subjects was a group of patients with neutral mechanical alignment who presented for ligamentous problems. A single observer measured mechanical alignment, anatomical alignment, anatomical-mechanical femoral angle and intra-articular bone morphology parameters with an accuracy of 1°. Varus OA group has less distal femoral valgus (mLDFA 89°) than control group (87°) and valgus OA group (mLDFA 85°). Varus OA group has same varus obliquity as control group (MPTA 87°) but more than valgus OA group (MPTA 90°). Joint Line Congruency Angle (JLCA) is 3°open on lateral side in varus and medially open in valgus OA group (2°). The non-arthritic valgus group presents a constitutional mechanical valgus of 184° Hip-Knee-Ankle (HKA) angle. Varus deformity in OA as measured with an HKA angle (HKA) <177° is a combination of distal femoral wear, tibial varus obliquity and lateral joint line opening. Valgus deformity in OA with an HKA > 183° is a combination of femoral distal joint line obliquity and wear combined with medial opening due to medial collateral ligament stretching. The clinical importance of bone morphotype analysis is that it shows the intra-articular potential of alignment correction when mechanical axis cuts are performed. Bone

  11. Valgus-varus motion of the knee in normal level walking and stair climbing.

    PubMed

    Yu, B; Stuart, M J; Kienbacher, T; Growney, E S; An, K-N

    1997-07-01

    OBJECTIVE: The knee valgus-varus moment and the knee angles were compared between normal level walking and stair climbing. DESIGN: Ten healthy subjects were tested for ascent, descent, and level walking. BACKGROUND: An understanding of the normal valgus-varus motion of the knee during stair climbing is needed to apply biomechanical analysis of stair climbing as a evaluation tool for knee osteoarthritis patients. METHODS: A motion analysis system, three force plates, and a flight of stairs were used to collect kinematic and kinetic data. The knee angles and moments were calculated from the collected kinematic and kinetic data. RESULTS: The knee varus angle for the maximum knee valgus moments in stair climbing was significantly greater than that in level walking. The knee valgus moment was significantly correlated to ground reaction forces and knee valgus-varus angle during stair climbing and level walking. CONCLUSIONS: There is a coupling between the knee valgus-varus motion and flexion-extension motion. Ground reaction forces are the major contributors to the within-subject variation in the knee valgus-varus moment during stair climbing and level walking. The knee valgus-varus angle is a major contributor to the between-subject variation in the knee valgus moment during stair climbing and level walking.

  12. Effect of First Tarsometatarsal Joint Derotational Arthrodesis on First Ray Dynamic Stability Compared to Distal Chevron Osteotomy.

    PubMed

    Klemola, Tero; Leppilahti, Juhana; Laine, Vesa; Pentikäinen, Ilkka; Ojala, Risto; Ohtonen, Pasi; Savola, Olli

    2017-08-01

    Hallux valgus alters gait, compromising first ray stability and function of the windlass mechanism at the late stance. Hallux valgus correction should restore the stability of the first metatarsal. Comparative studies reporting the impact of different hallux valgus correction methods on gait are rare. We report the results of a case-control study between distal chevron osteotomy and first tarsometatarsal joint derotational arthrodesis (FTJDA). Two previously studied hallux valgus cohorts were matched: distal chevron osteotomy and FTJDA. Seventy-seven feet that underwent distal chevron osteotomy (chevron group) and 76 feet that underwent FTJDA (FTJDA group) were available for follow-up, with a mean of 7.9 years (range, 5.8-9.4 years) and 5.1 years (range, 3.0-8.3 years), respectively. Matching criteria were the hallux valgus angle (HVA) and a follow-up time difference of a maximum 24 months. Two matches were made: according to the preoperative HVA and the HVA at late follow-up. Matching provided 30 and 31 pairs, respectively. Relative impulses (%) of the first toe (T1) and metatarsal heads 1 to 5 (MTH1-5), weightbearing radiographs, and American Orthopaedic Foot & Ankle Society (AOFAS) (hallux metatarsophalangeal-interphalangeal [MTP-IP]) scores were studied. The relative impulse of MTH1 was higher in the FTJDA group, whereas a central dynamic loading pattern was seen in the chevron group. This result remained when relative impulses were analyzed according to the postoperative HVA. The mean difference in the HVA at follow-up was 6.2 degrees (95% confidence interval, 3.0-9.5; P = .001) in favor of the FTJDA group. The dynamic loading capacity of MTH1 was higher in the FTJDA group in comparison to the chevron group. The follow-up HVA remained better in the FTJDA group. Level III, case-control study.

  13. Plasma HVA in psychiatric patients: longitudinal studies.

    PubMed

    Javaid, J I; Sharma, R P; Janicak, P G; Davis, J M

    1990-01-01

    Plasma homovanillic acid (pHVA) was measured in 40 inpatients (25 schizophrenic and 15 nonschizophrenic patients) who underwent up to 3 weeks of drug washout. Schizophrenic patients were then treated with trifluoperazine for 4 weeks, and weekly behavioral and pHVA measures were obtained. The baseline pHVA had no relationship to age, sex, washout period, diagnosis, or behavioral rating scores. In schizophrenic patients, the baseline pHVA did not differ significantly from any value obtained during 4 weeks of treatment. Although there was significant improvement in clinical symptoms, this was not related to changes in pHVA. Further, changes in any of the four Brief Psychiatric Rating Scale (BPRS) factors (i.e., positive symptoms, negative symptoms, hostility/suspicion, or anxiety/depression) were not correlated with changes in pHVA. Although other studies have reported a positive correlation between pHVA and psychotic symptoms, results of this study suggest that any observed relationship between pHVA and psychosis must be carefully interpreted.

  14. Comparison of the proximal chevron and Ludloff osteotomies for the correction of hallux valgus.

    PubMed

    Choi, Woo Jin; Yoon, Han Kook; Yoon, Hang Seob; Kim, Bom Soo; Lee, Jin Woo

    2009-12-01

    Although several studies have described good results of proximal chevron and Ludloff osteotomies, there have been no studies comparing the results of these two techniques at a single institution. We consecutively evaluated 46 patients who underwent proximal chevron osteotomies and 52 patients who underwent Ludloff osteotomies. Patients were evaluated by preoperative and postoperative weight bearing radiographs and the American Orthopaedic Foot and Ankle Society (AOFAS) hallux MP score. Both groups had similarly high AOFAS scores and good correction by radiographic parameters. No statistically significant differences were found with respect to correction of hallux valgus angle (HVA) and intermetatarsal angle (IMA) between the two groups. Significant shortening of the first metatarsal was found after Ludloff osteotomy (p < 0.05). At 6 weeks after surgery, the pain subscore was significantly lower in the proximal chevron group than in the Ludloff group (p < 0.05). The proximal chevron and Ludloff osteotomies yielded equivalent clinical and radiological results. The Ludloff osteotomy with lag screw fixation is more stable and does not require postoperative hardware removal, although it is technically demanding and has a tendency toward greater shortening of the first metatarsal.

  15. A comparison of men's and women's strength to body mass ratio and varus/valgus knee angle during jump landings.

    PubMed

    Haines, Tracie L; McBride, Jeffrey M; Triplett, N Travis; Skinner, Jared W; Fairbrother, Kimberly R; Kirby, Tyler J

    2011-10-01

    The purpose of this investigation was to compare valgus/varus knee angles during various jumps and lower body strength between males and females relative to body mass. Seventeen recreationally active females (age: 21.94 ± 2.59 years; height: 1.67 ± 0.05 m; mass: 64.42 ± 8.39 kg; percent body fat: 26.89 ± 6.26%; squat one-repetition maximum: 66.18 ± 19.47 kg; squat to body mass ratio: 1.03 ± 0.28) and 13 recreationally active males (age: 21.69 ± 1.65 years; height: 1.77 ± 0.07 m; mass: 72.39 ± 9.23 kg; percent body fat: 13.15 ± 5.18%; squat one-repetition maximum: 115.77 ± 30.40 kg; squat to body mass ratio: 1.59 ± 0.31) performed a one-repetition maximum in the squat and three of each of the following jumps: countermovement jump, 30 cm drop jump, 45 cm drop jump, and 60 cm drop jump. Knee angles were analysed using videography and body composition was analysed by dual-energy X-ray absorptiometry to allow for squat to body mass ratio and squat to fat free mass ratio to be calculated. Significant differences (P ≤ 0.05) were found between male and female one-repetition maximum, male and female squat to body mass ratio, and male and female squat to fat free mass ratio. Significant differences were found between male and female varus/valgus knee positions during maximum flexion of the right and left leg in the countermovement jump, drop jump from 30 cm, drop jump from 45 cm, and drop jump from 60 cm. Correlations between varus/valgus knee angles and squat to body mass ratio for all jumps displayed moderate, non-significant relationships (countermovement jump: r = 0.445; drop jump from 30 cm: r = 0.448; drop jump from 45 cm: r = 0.449; drop jump from 60 cm: r = 0.439). In conclusion, males and females have significantly different lower body strength and varus/valgus knee position when landing from jumps.

  16. Being overweight has limited effect on SCARF osteotomy outcome for hallux valgus correction.

    PubMed

    Milczarek, Marcin A; Milczarek, Julia J; Tomasik, Bartłomiej; Łaganowski, Przemysław; Nowak, Krzysztof; Domżalski, Marcin

    2017-04-01

    The purpose of this study was to investigate the association between body mass index (BMI) and the results of SCARF osteotomy of the first metatarsal for hallux valgus (HV) correction, as the literature on this is scant. This prospective study was carried out between 2011 and 2015. One hundred and thirty-three patients diagnosed with moderate to severe HV underwent a SCARF corrective osteotomy. We divided the patients into two groups according to their BMI: normal and overweight. Postoperative follow-up was two years. All patients were examined twice by two medical doctors simultaneously: pre-operatively and post-operatively at two years' follow-up. Data collected included biometrical records, X-rays [HV angle (HVA), intermetatarsal angle (IMA), American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal Index (AOFAS-HMI) and visual analogue scale (VAS) for pain and satisfaction]. There was a significant difference between patient age (p = 0.001), age at onset (p < 0.001) and AOFAS-HMI (p = 0.035) at follow-up. Other parameters were similar in both groups. Regardless of BMI, the radiological outcome was comparable. Despite a significant difference in AOFAS-HMI results, pain and satisfaction level were similar. The authors agreed that high BMI has protective role in the prevalence of HV.

  17. Effects of a lower limb functional exercise programme aimed at minimising knee valgus angle on running kinematics in youth athletes.

    PubMed

    Sheerin, Kelly R; Hume, Patria A; Whatman, Chris

    2012-11-01

    To investigate the effectiveness of 8-weeks of lower limb functional exercises on frontal plane hip and knee angles during running in youth athletes. Pre- and post-intervention quantitative experimental. Nineteen athletes (11 male, 8 female, 11.54 ± 1.34 years) from a long-term athletic development programme had 3-dimensional running gait measured pre and post an 8-week exercise intervention. Youth athletes randomised to control (upper limb strengthening exercises) or experimental (lower limb functional exercises aimed at minimising knee valgus angle) interventions completed the exercises during the first 10 min of training, three mornings a week. Pre- and post-parallel groups' analysis provided estimates of intervention effects for control and experimental groups. Differences in pre- to post-intervention changes in mean frontal plane angles between control and experimental groups were trivial for the left hip (0.1°) and right knee (-0.3°). There was a small beneficial decrease in right hip joint angle (0.4°) but a very large (ES = 0.77, CI 0.1-3.7) detrimental increase in left knee valgus angle (1.9°) between groups. The 8-week lower limb functional exercises had little beneficial effects on lower limb hip and knee mechanics in youth athletes aged 9-14 years. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Lateral sesamoid position in hallux valgus: correlation with the conventional radiological assessment.

    PubMed

    Agrawal, Yuvraj; Desai, Aravind; Mehta, Jaysheel

    2011-12-01

    We aimed to quantify the severity of the hallux valgus based on the lateral sesamoid position and to establish a correlation of our simple assessment method with the conventional radiological assessments. We reviewed one hundred and twenty two dorso-plantar weight bearing radiographs of feet. The intermetatarsal and hallux valgus angles were measured by the conventional methods; and the position of lateral sesamoid in relation to first metatarsal neck was assessed by our new and simple method. Significant correlation was noted between intermetatarsal angle and lateral sesamoid position (Rho 0.74, p < 0.0001); lateral sesamoid position and hallux valgus angle (Rho 0.56, p < 0.0001). Similar trends were noted in different grades of severity of hallux valgus in all the three methods of assessment. Our method of assessing hallux valgus deformity based on the lateral sesamoid position is simple, less time consuming and has statistically significant correlation with that of the established conventional radiological measurements. Copyright © 2011 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  19. Role of intraoperative varus stress test for lateral soft tissue release during chevron bunion procedure.

    PubMed

    Kim, Hyong-Nyun; Suh, Dong-Hyun; Hwang, Pil-Sung; Yu, Sun-O; Park, Yong-Wook

    2011-04-01

    The purpose of this study was to evaluate the clinical results of distal chevron osteotomy performed in conjunction with selective lateral soft tissue release. The criterion for doing a lateral soft tissue release was assessed by determining the ease and completeness of passive hallux valgus correction at the time of surgery. Between August 2005 and November 2007, 48 feet in 43 patients classified as having mild to moderate hallux valgus were retrospectively studied. Distal chevron osteotomy without lateral soft tissue release was performed in 26 cases (Group 1) when passive correction of the hallux valgus deformity was possible. Distal chevron osteotomy with lateral soft tissue release was performed in 22 cases (Group 2) when passive correction was not possible. Average followup was 23 (range, 12 to 28) months. Clinical results were assessed using radiographic parameters [hallux valgus angle (HVA), first and second intermetatarsal angle (1,2 IMA)], AOFAS scale and patient's subjective satisfaction. For Group 1: the average correction of HVA was 12.8 degrees, the average correction of IMA was 4.7 degrees, and the AOFAS score improved an average of 29.2 points at the last followup. Thirteen patients were very satisfied and ten patients were satisfied with the results. No patient was dissatisfied. For Group 2: the average correction of HVA was 19.1 degrees, the average correction of IMA was 7 degrees and AOFAS score improved at an average of 31.8 points at the last followup. Twelve patients were very satisfied, seven patients were satisfied and one patient, who had stiffness of the first metatarsophalangeal joint, was dissatisfied with the result. Distal chevron osteotomy with selective lateral soft tissue release based on the ability to passively correct the hallux valgus deformity lead to safe and stable correction.

  20. Short-Term Radiographic Outcome After Distal Chevron Osteotomy for Hallux Valgus Using Intramedullary Plates With an Amended Algorithm for the Surgical Management of Hallux Valgus.

    PubMed

    Matsumoto, Takumi; Gross, Christopher E; Parekh, Selene G

    2018-03-01

    Distal Chevron osteotomy is a well-established surgical procedure for mild to moderate hallux valgus deformity. Many methods have been described for fixation of osteotomy site; secure fixation, enabling large displacement of the metatarsal head, is one of the essentials of this procedure. The purpose of the present study was to evaluate the short-term radiographic outcome of a distal Chevron osteotomy using an intramedullary plate for the correction of hallux valgus deformity. The present study evaluated 37 patients (40 feet) who underwent distal Chevron osteotomy using an intramedullary plate by periodic radiographs obtained preoperatively and at 4 weeks, 8 weeks, 3 months, and 6 months postoperatively. Correction of the hallux valgus angle averaged 17.8°, intermetatarsal angle 7.4°, distal metatarsal articular angle 2.7°, and sesamoid position 1.4 stages at 3 months postoperatively. The average lateral shift of the capital fragment was 6.5 mm. All patients achieved bone union, and there were no cases of dislocation, displacement, or avascular necrosis of the metatarsal head fragment. In conclusion, a distal Chevron osteotomy using an intramedullary plate was a favorable method for the correction of mild to moderate hallux valgus deformity. Level IV: Case series.

  1. Factors affecting femoral rotational angle based on the posterior condylar axis in gap-based navigation-assisted total knee arthroplasty for valgus knee.

    PubMed

    Lee, Sung-Sahn; Lee, Yong-In; Kim, Dong-Uk; Lee, Dae-Hee; Moon, Young-Wan

    2018-01-01

    Achieving proper rotational alignment of the femoral component in total knee arthroplasty (TKA) for valgus knee is challenging because of lateral condylar hypoplasia and lateral cartilage erosion. Gap-based navigation-assisted TKA enables surgeons to determine the angle of femoral component rotation (FCR) based on the posterior condylar axis. This study evaluated the possible factors that affect the rotational alignment of the femoral component based on the posterior condylar axis. Between 2008 and 2016, 28 knees were enrolled. The dependent variable for this study was FCR based on the posterior condylar axis, which was obtained from the navigation system archives. Multiple regression analysis was conducted to identify factors that might predict FCR, including body mass index (BMI), Kellgren-Lawrence grade (K-L grade), lateral distal femoral angles obtained from the navigation system and radiographs (NaviLDFA, XrayLDFA), hip-knee-ankle (HKA) axis, lateral gap under varus stress (LGVS), medial gap under valgus stress (MGVS), and side-to-side difference (STSD, MGVS - LGVS). The mean FCR was 6.1° ± 2.0°. Of all the potentially predictive factors evaluated in this study, only NaviLDFA (β = -0.668) and XrayLDFA (β = -0.714) predicted significantly FCR. The LDFAs, as determined using radiographs and the navigation system, were both predictive of the rotational alignment of the femoral component based on the posterior condylar axis in gap-based TKA for valgus knee. A 1° increment with NaviLDFA led to a 0.668° decrement in FCR, and a 1° increment with XrayLDFA led to a 0.714° decrement. This suggests that symmetrical lateral condylar hypoplasia of the posterior and distal side occurs in lateral compartment end-stage osteoarthritis with valgus deformity.

  2. Effects of flexor-pronator muscle loading on valgus stability of the elbow with an intact, stretched, and resected medial ulnar collateral ligament.

    PubMed

    Udall, John H; Fitzpatrick, Michael J; McGarry, Michelle H; Leba, Thu-Ba; Lee, Thay Q

    2009-01-01

    The medial ulnar collateral ligament (MUCL) is an important passive stabilizer to the valgus stresses that athletes experience during overhead throwing motion. However, the role of the flexor-pronator muscles as active stabilizers to valgus stress is not well defined in the literature. The objectives of this study were to quantify the relative contribution of the individual flexor-pronator muscles to valgus stability of the elbow and how this relationship was affected by ligament status. A custom elbow testing system and Microscribe 3DLX were used for biomechanical testing. Flexor-pronator muscles were loaded to simulate contraction, and the valgus angle of the elbow was measured in eight cadaveric specimens at 30 degrees , 60 degrees , and 90 degrees of elbow flexion with 3 different valgus torques applied to the forearm. Loads based on muscle cross-sectional area were applied to the flexor carpi ulnaris (FCU), flexor digitorum superficialis (FDS), and pronator teres (PT). The effect of each muscle was evaluated by unloading the individual muscle while the other 2 remained loaded, resulting in 5 loading conditions: no muscles loaded, all muscles loaded, unloaded FCU, unloaded FDS, and unloaded PT. Valgus angle was measured for 3 MUCL ligament conditions: intact, stretched, and cut. The effect of muscle loading on valgus angle was similar for each ligament condition. Loading the flexor-pronator muscles significantly decreased valgus angle of the elbow in all testing conditions (P < .01). Unloading the FDS significantly increased valgus angle compared to all muscles loaded in all testing conditions (P < .016). Unloading the FCU and PT significantly increased valgus angle in less than half of the testing conditions. The FDS, PT, and FCU are all active stabilizers of the elbow to valgus stress. The FDS is the biggest contributor amongst the flexor-pronator muscles.

  3. [Distal soft-tissue procedure in hallux valgus deformity].

    PubMed

    Arbab, D; Wingenfeld, C; Frank, D; Bouillon, B; König, D P

    2016-04-01

    Distal, lateral soft tissue release to restore mediolateral balance of the first metatarsophalangeal (MTP) joint in hallux valgus deformity. Incision of the adductor hallucis tendon from the fibular sesamoid, the lateral capsule, the lateral collateral ligament, and the lateral metatarsosesamoid ligament. Hallux valgus deformities or recurrent hallux valgus deformities with an incongruent MTP joint. General medical contraindications to surgical interventions. Painful stiffness of the MTP joint, osteonecrosis, congruent joint. Relative contraindications: connective tissue diseases (Marfan syndrome, Ehler-Danlos syndrome). Longitudinal, dorsal incision in the first intermetatarsal web space between the first and second MTP joint. Blunt dissection and identification of the adductor hallucis tendon. Release of the adductor tendon from the fibular sesamoid. Incision of the lateral capsule, the lateral collateral ligament, and the lateral metatarsosesamoid ligament. Postoperative management depends on bony correction. In joint-preserving procedures, dressing for 3 weeks in corrected position. Subsequently hallux valgus orthosis at night and a toe spreader for a further 3 months. Passive mobilization of the first MTP joint. Postoperative weight-bearing according to the osteotomy. A total of 31 patients with isolated hallux valgus deformity underwent surgery with a Chevron and Akin osteotomy and a distal medial and lateral soft tissue balancing. The mean preoperative intermetatarsal (IMA) angle was 12.3° (range 11-15°); the hallux valgus (HV) angle was 28.2° (25-36°). The mean follow-up was 16.4 months (range 12-22 months). The mean postoperative IMA correction ranged between 2 and 7° (mean 5.2°); the mean HV correction was 15.5° (range 9-21°). In all, 29 patients (93%) were satisfied or very satisfied with the postoperative outcome, while 2 patients (7%) were not satisfied due to one delayed wound healing and one recurrent hallux valgus deformity. There were no

  4. The biomechanical effect of increased valgus on total knee arthroplasty: a cadaveric study.

    PubMed

    Bryant, Brandon J; Tilan, Justin U; McGarry, Michelle H; Takenaka, Nobuyuki; Kim, William C; Lee, Thay Q

    2014-04-01

    The effects of valgus load on cadaveric knees following total knee arthroplasty (TKA) were investigated using a custom testing system. TKAs were performed on 8 cadaveric knees and tested at 0°, 30°, and 60° knee flexion in both neutral and 5° valgus. Fuji pressure sensitive film was used to quantify contact areas and pressures and MCL strain was determined using a Microscribe digitizing system. Lateral tibiofemoral pressures increased (P < 0.05) at all knee flexion angles with valgus loading. Patellofemoral contact characteristics did not change significantly (P > 0.05). Significant increases in strain were observed along the anterior and posterior border of the MCL at all knee flexion angles. These findings suggest that valgus loading increases TKA joint contact pressures and MCL strain with increasing knee flexion which may increase implant instability. © 2014.

  5. Outcomes of proximal chevron osteotomy for moderate versus severe hallux valgus deformities.

    PubMed

    Moon, Jae-Young; Lee, Keun-Bae; Seon, Jong Keun; Moon, Eun-Sun; Jung, Sung-Taek

    2012-08-01

    Proximal chevron osteotomy with a distal soft tissue procedure has been widely used to treat moderate to severe hallux valgus deformities. However, there have been no studies comparing the results of proximal chevron osteotomy between patients with moderate and severe hallux valgus. We compared the results of this procedure among these groups. A retrospective review of 95 patients (108 feet) that underwent proximal chevron osteotomy and distal soft tissue procedure for moderate and severe hallux valgus was conducted. The 108 feet were divided into two groups: moderate hallux valgus (Group A) and severe hallux valgus (Group B). Group A was composed of 57 feet (52 patients) and Group B of 51 feet (43 patients). Average followup was 45 months. Mean American Orthopedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal scores were 54.1 points in Group A and 53.0 points in Group B preoperatively, and these improved to 90.8 and 92.6, respectively, at the last followup. Mean hallux valgus angles in Groups A and B reduced from 32.3 and 40.8 degrees, preoperatively to 10.7 and 13.2 degrees, postoperatively. Similarly, mean first intermetatarsal angles in Groups A and B reduced from 15.0 and 19.2 degrees, preoperatively to 9.0 and 9.2 degrees, postoperatively. The clinical and radiographic outcomes of proximal chevron osteotomy with a distal soft tissue procedure were found to be comparable for moderate and severe hallux valgus. Accordingly, our results suggest that this procedure provides an effective and reliable means of correcting hallux valgus regardless of severity of deformity.

  6. Evolution of plasma homovanillic acid (HVA) in chronic schizophrenic patients treated with haloperidol.

    PubMed

    Galinowski, A; Poirier, M F; Aymard, N; Leyris, A; Beauverie, P; Bourdel, M C; Loo, H

    1998-06-01

    In a 4-week study of 14 drug-free schizophrenic patients (according to DSM-III-R), free and conjugated fractions of plasma homovanillic acid (pHVA) were repeatedly measured. Free HVA levels decreased during the first 2 h of haloperidol intake (P < 0.03). Conjugated HVA levels slowly decreased during the following weeks (P < 0.05), while free HVA levels remained stable. After 4 weeks, free HVA levels remained unchanged 2 h after morning haloperidol intake, but conjugated HVA levels tended to increase. In haloperidol responders, at baseline the free/total HVA ratio was significantly higher than that in non-responders (P < 0.01). Tolerant patients, i.e. those whose post-treatment free HVA levels decreased below pre-treatment levels, were not found to respond better to haloperidol than non-tolerant patients. The balance between free and conjugated pHVA may be a better reflection of the action of haloperidol than free pHVA levels and it may be of prognostic value in terms of drug response.

  7. Leg stiffness, valgus knee motion, and Q-angle are associated with hypertrophic soft patella tendon and idiopathic knee pain in adolescent basketball players.

    PubMed

    Satkunskiene, Danguole; Mickevicius, Mantas; Snieckus, Audrius; Kamandulis, Sigitas

    2017-01-01

    Knee pain without knee degenerative symptoms is a common phenomenon among young basketball players. The aim of this study was to identify factors predisposing young basketball players to suffer from knee pain. The study involved 20 male adolescent (14-15 years) basketball players who were divided into two equal groups based on knee pain symptoms. Legs torque was tested on an isokinetic dynamometer. The length, elongation and the cross-sectional area (CSA) of the patellar tendon were measured with ultrasonography. Quadriceps angle (Q-angle), knee valgus motion, and joint angular displacement in the sagittal plane were analyzed using video recording during countermovement jump. Ground reaction force was measured using a force platform. Knee pain (KP) participants had a significantly lower Q-angle (P=0.045) and lower maximum varus knee angle (P=0.035), and a greater knee inside displacement (P=0.039) during squat phase. In the KP group, the CSA at the top of the tendon was significantly greater than in the middle (P=0.006) and at the bottom (P=0.039). Absolute tendon stiffness (P=0.013) and Young's modulus (P=0.034) were significantly lower in the KP group compared with controls. Leg stiffness during landing was significantly greater in the control group (P=0.015). Leg stiffness, valgus knee motion, and Q-angle are associated with hypertrophic soft patella tendon and idiopathic knee pain in adolescent basketball players.

  8. Valgus osteotomy and repositioning and fixation with a dynamic hip screw and a 135º single-angled barrel plate for un-united and neglected femoral neck fractures.

    PubMed

    Gupta, Sameer; Kukreja, Sunil; Singh, Vivek

    2014-04-01

    To review the outcome of 60 patients who underwent valgus subtrochanteric osteotomy and its repositioning for un-united and neglected femoral neck fractures. 60 patients (mean age, 35 years) underwent valgus subtrochanteric osteotomy and repositioning of the osteotomy and fixation with a dynamic hip screw and a 135° single-angled barrel plate for closed un-united femoral neck fractures after failed internal fixation (n=27) or neglected (>3 weeks) fractures (n=33). The most common fracture type was transcervical (n=48), followed by subcapital (n=6) and basal (n=6). All patients had displaced femoral neck fractures (Garden types 3 and 4). According to the Pauwel angle, 45 fractures were type 2 (30º-70º) and 15 were type 3 (>70º). Patients were followed up for a mean of 3.5 (range, 2-7.5) years. The mean Pauwel angle of the fracture was corrected from 65° (range, 50°-89°) to 26° (range, 25°-28°). Bone union was achieved in 56 patients after a mean of 3.9 (range, 3-5.5) months. The mean Harris hip score improved from 65 to 87.5. Outcome was excellent in 30 patients, good in 24, and poor in 6. Four of the patients developed avascular necrosis; 2 of whom nonetheless achieved a good outcome. Valgus osteotomy and repositioning and fixation with a dynamic hip screw and a 135° single-angled barrel plate was effective treatment for un-united and neglected femoral neck fractures.

  9. Primary and coupled motions of the native knee in response to applied varus and valgus load.

    PubMed

    Gladnick, Brian P; Boorman-Padgett, James; Stone, Kyle; Kent, Robert N; Cross, Michael B; Mayman, David J; Pearle, Andrew D; Imhauser, Carl W

    2016-06-01

    Knowledge of the complex kinematics of the native knee is a prerequisite for a successful reconstructive procedure. The aim of this study is to describe the primary and coupled motions of the native knee throughout the range of knee flexion, in response to applied varus and valgus loads. Twenty fresh-frozen cadaver knees were affixed to a six degree of freedom robotic arm with a universal force-moment sensor, and loaded with a 4Nm moment in varus and valgus at 0, 15, 30, 45, and 90° of knee flexion. The resulting tibiofemoral angulation, displacement, and rotation were recorded. For each parameter investigated, the knee joint demonstrated more laxity at higher flexion angles. Varus angulation increased progressively from zero (2.0° varus) to 90 (5.2° varus) degrees of knee flexion (p<0.001). Valgus angulation also increased progressively, from zero (1.5° valgus) to 90 (3.9° valgus) degrees of knee flexion (p<0.001). At all flexion angles, the magnitude of tibiofemoral angle deviation was larger with varus than with valgus loading (p<0.05). We conclude that the native knee exhibits small increases in coronal plane laxity as the flexion angle increases, and that the knee has generally more laxity under varus load than with valgus load throughout the Range of Motion (ROM). Larger differences in laxity of more than 2 to 3°, or peak laxity specifically during the range of mid-flexion, were not found in our cadaver model and are not likely to represent normal coronal plane kinematics. Level V, biomechanical cadaveric study. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. [Application of three-dimensional printing technology to design individual angle section on Chevron of hallux valgus osteotomy].

    PubMed

    Zhang, Yu-Hang; Bi, Da-Wei; Chen, Yi-Min; Zu, Gang; Ma, Hai-Tao

    2018-03-25

    To explore clinical application of three-dimensional printing technology to design individual angle section on Chevron of hallux valgus osteotomy. From May 2013 to May 2016, 47 patients(66 feet) with mild to moderate hallux valgus treated by Chevron osteotomy according to different preoperative design were divided into computer osteotomy group(group A) and traditional osteotomy group(group B). In group A, there were 25 patients (33 feet), including 4 males(5 feet) and 21 females(28 feet) with an average age of (47.88±6.08) years old, average weight IMA was (13.58±1.15) degree, AOFAS score was 59.00±5.86, and treated individual 3D printing technology to design operation scheme. While in group B, there were 22 patients (33 feet), including 3 males (3 feet) and 19 females (28 feet) with an average age of (48.16±6.16) years old, average weight IMA was(13.51±1.14) degree, AOFAS score was 60.67±5.85, and treated with osteotomy according to surgical experience. Operation time, blood loss, hospital stays, VAS score at 1 week after operation, wound healing and improvement of postoperative weight-bearing intermetatarsal angle(IMA) were compared between two groups, AOFAS score system was used to evaluate ankle function after surgery. There was no significant difference in following-up between group A 12.41±2.32 and group B 11.73±2.76. There was 1 patient in group B were excluded. Others perform good wounds healing on the first stage after operation. There were no significant differences in operation time, blood loss, hospital stays and VAS score at 1 week after operation( P <0.05); IMA in group A was (5.21±0.88)°, (6.42±0.85)° in group B, and had significant differences between two groups ( t =5.68, P <0.05). There was obvious meaning in AOFAS score between group A 88.15±5.19 and group B 82.90±5.01( t =4.14, P <0.05). Fourteen feet in group A obtained excellent results and 19 feet good, while 5 feet in group B obtained excellent results and 27 feet good

  11. Hallux abductus interphalangeus in normal feet, early-stage hallux limitus, and hallux valgus.

    PubMed

    Castillo-Lopez, Jose M; Ramos-Ortega, Javier; Reina-Bueno, Maria; Domínguez-Maldonado, Gabriel; Palomo-Toucedo, Inmaculada C; Munuera, Pedro V

    2014-03-01

    Excessive deviation of the distal phalanx in abduction frequently occurs in advanced stages of hallux rigidus but not in hallux valgus. Therefore, theoretically there should be no significant differences in the hallux interphalangeal angle (HIPA) between individuals with normal feet, those with hallux valgus, and those with mild hallux limitus. The objective of the present study was thus to determine if significant differences in HIPA exist in the early stages of hallux valgus or hallux limitus deformities. The hallux interphalangeal angle was measured in three groups of participants: a control group with normal feet (45 participants), a hallux valgus group (49 participants), and a hallux limitus group (48 participants). Both of the pathologies were at an early stage. A dorsoplantar radiograph under weightbearing conditions was taken for each individual, and measurements (HIPA and hallux abductus angle [HAA]) were taken using AutoCAD (Autodesk Inc, San Rafael, California) software. Intergroup comparisons of HIPA, and correlations between HIPA, HAA, and hallux dorsiflexion were calculated. The comparisons revealed no significant differences in the values of HIPA between any of the groups (15.2 ± 5.9 degrees in the control group, 15.5 ± 3.9 degrees in the hallux valgus group, and 16.15 ± 4.3 in the hallux limitus group; P  =  0.634). The Pearson correlation coefficients in particular showed no correlation between hallux dorsiflexion, HAA, and HIPA. For the study participants, there were similar deviations of the distal phalanx of the hallux with respect to the proximal phalanx in normal feet and in feet with the early stages of the hallux limitus and hallux valgus deformities.

  12. First metatarsal length change after basilar closing wedge osteotomy for hallux valgus.

    PubMed

    Day, Thomas; Charlton, Timothy P; Thordarson, David B

    2011-05-01

    Hallux valgus deformities with large intermetatarsal angles require a more proximal metatarsal procedure to adequately correct the deformity. Due to the relative ease of a closing wedge osteotomy, this technique was adopted but with concern over first metatarsal shortening. In this study, we primarily evaluated angular correction and first metatarsal shortening. We evaluated 70 feet in 57 patients (average age, 54 years) with 52 female and five male. The average followup was 14 (range, 6 to 45) months. The charts were reviewed for the presence of metatarsalgia. Digital radiographic measurements were made for pre- and postoperative hallux valgus and intermetatarsal angles, dorsiflexion angle of the first metatarsal, and absolute and relative shortening of the first metatarsal. The average hallux valgus angle improved from 31 to 11 degrees (p < 0.0001) and intermetatarsal angle from 13.2 to 4.4 angles (p < 0.0001). The absolute shortening of the first metatarsal was 2.2 mm and relative shortening was 0.6 mm. There was 1.3 degrees of dorsiflexion on average. Excellent correction of the deformity with minimal dorsiflexion or new complaints of metatarsalgia was found with this technique. The new method of assessing the relative shortening found to be less than the absolute shortening, which we feel more accurately reflects the functional length of the first metatarsal.

  13. A biomodal distribution of plasma HVA/MHPG in the psychoses.

    PubMed

    Ottong, S E; Garver, D L

    1997-03-24

    In an attempt to estimate dopamine production in psychotic patients, pHVA and pMHPG were assessed from morning blood samples of fasting, neuroleptic-free patients. The (pHVA/pMHPG) ratio was bimodally distributed. The upper mode delineated a cluster of psychotics with excess central dopamine activity. Despite a comparable duration of illness, the high ratio cluster had an earlier age of onset and a more complete subacute response during neuroleptic treatment than did lower ratio patients. Comparisons were made between these clusters and clusters defined by the distribution of pHVA alone. The data suggest a disorder of feedback control of central dopamine metabolism in the high pHVA/pMHPG cluster.

  14. Correlation of Postoperative Position of the Sesamoids After Chevron Osteotomy With Outcome.

    PubMed

    Shi, Glenn G; Henning, Peter; Marks, Richard M

    2016-03-01

    Postoperative incomplete reduction of the sesamoids has been identified as a potential risk factor for hallux valgus recurrence after proximal osteotomy. However, it is not known whether the postoperative sesamoid position is a risk factor in hallux valgus correction via distal chevron osteotomy with or without dorsal webspace release (DWSR). In this retrospective study, 169 patients who underwent distal chevron osteotomy with or without DWSR were reviewed. Preoperative and postoperative (6 weeks, 6 months, 12 months) weightbearing radiographs were evaluated. Functional hallux valgus angle (HVA), intermetatarsal angle (IMA), and the position of the tibial sesamoid were graded using the center of head method. Seventy-six radiographs were available for review at the 12-month follow-up. Of these, 41 patients underwent DWSR procedure and 35 did not. In both groups, correction of all 3 parameters (HVA, IMA, tibial sesamoid position) were significant at the 12-month follow-up. Comparison of the postoperative results of the 2 groups showed no statistically significant differences. Four feet demonstrated displaced sesamoid position at the 12-month follow-up, with radiographic evidence of recurrence in just one. No significant relationship was found between postoperative sesamoid position and hallux valgus recurrence that occurred in 4 feet. Combining DWSR with a distal chevron osteotomy did not delay healing or increase risk of avascular necrosis, but it did not significantly improve angular measurements or sesamoid position. The concept that postoperative sesamoid position can be used to predict hallux valgus recurrence was not supported by our results when looking at distal chevron correction. Level III, retrospective comparative study. © The Author(s) 2015.

  15. Short-Term Effects of Kinesiotaping on Pain and Joint Alignment in Conservative Treatment of Hallux Valgus.

    PubMed

    Karabicak, Gul Oznur; Bek, Nilgun; Tiftikci, Ugur

    2015-10-01

    The main aim of this study was to measure short-term effects of kinesiotaping on pain and joint alignment in the conservative treatment of hallux valgus. Twenty-one female patients diagnosed with a total of 34 feet with hallux valgus (13 bilateral, 6 right, and 2 left) participated in this study. Kinesiotaping was implemented after the first assessment and renewed in days 3, 7, and 10. The main outcome measures were pain, as assessed using visual analog scale, and hallux adduction angle, as measured by goniometry. Secondary outcome measure was patients' functional status, as measured by Foot Function Index and the hallux valgus scale of the American Orthopaedic Foot and Ankle Society (AOFAS). The radiographic results were also measured before and after 1 month of treatment. The Wilcoxon test was used to compare the differences between initial and final scores of AOFAS, as well as FFI scales and hallux valgus angle assessment scores. There was a significant reduction in goniometric measurement of hallux valgus angle (P = .001). There was a significant reduction in pain intensity (P = .001) and AOFAS and Foot Function Index scores at the end of the treatment (P = .001 and P = .001, respectively). There was a significant difference between radiographic results in 1-month control (P = .009). For this group of female patients, pain and joint alignment were improved after a 10-day kinesiotape implementation in patients with hallux valgus. The findings showed short-term decreased pain and disability in hallux valgus deformity. Copyright © 2015 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

  16. Geometry of the Valgus Knee: Contradicting the Dogma of a Femoral-Based Deformity.

    PubMed

    Eberbach, Helge; Mehl, Julian; Feucht, Matthias J; Bode, Gerrit; Südkamp, Norbert P; Niemeyer, Philipp

    2017-03-01

    Realignment osteotomies of valgus knee deformities are usually performed at the distal femur, as valgus alignment is considered to be a femoral-based deformity. This dogma, however, has not been proven in a large patient population. Valgus malalignment may also be caused by a tibial deformity or a combined tibial and femoral deformity. The purposes of this study were (1) to analyze the coronal geometry of patients with valgus malalignment and identify the location of the underlying deformity and (2) to investigate the proportion of cases that require realignment osteotomy at the tibia, the femur, or both locations to avoid an oblique joint line. Cross-sectional study; Level of evidence, 3. The analysis included 420 standing full-leg radiographs of patients with valgus malalignment (mechanical femorotibial angle [mFTA], ≥4°). A systematic analysis of the coronal leg geometry was performed including the mFTA, mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), and joint-line convergence angle (JLCA). The localization of the deformity was determined according to the malalignment test described by Paley, and patients were assigned to 1 of 4 groups: femoral-based valgus deformity, tibial-based valgus deformity, femoral- and tibial-based valgus deformity, or intra-articular/ligamentary-based valgus deformity. Subsequently, the ideal osteotomy site was identified with the goal of a postoperative change of the joint line of two different maximum values, ±2° and ±4°, from its physiological varus position of 3°. Measurements of the coronal alignment revealed a mean (±SD) mFTA of 7.4° ± 4.3° (range, 4°-28.2°). The mean mLDFA and mean mMPTA were 84.8° ± 2.4° and 90.9° ± 2.6°, respectively. The mean JLCA was 1.2° ± 3.1°. The majority (41.0%) of valgus deformities were tibial based, 23.6% were femoral based, 26.9% were femoral and tibial based, and 8.6% were intra-articular/ligamentary based. To achieve a

  17. Z-osteotomy in hallux valgus: clinical and radiological outcome after Scarf osteotomy

    PubMed Central

    Jäger, Marcus; Schmidt, Michael; Wild, Alexander; Bittersohl, Bernd; Courtois, Susanne; Schmidt, Troy G.; Rüdiger, Krauspe

    2009-01-01

    Correction osteotomies of the first metatarsal are common surgical approaches in treating hallux valgus deformities whereas the Scarf osteotomy has gained popularity. The purpose of this study was to analyze short- and mid-term results in hallux valgus patients who underwent a Scarf osteotomy. The subjective and radiological outcome of 131 Scarf osteotomies (106 hallux valgus patients, mean age: 57.5 years, range: 22–90 years) were retrospectively analyzed. Mean follow-up was 22.4 months (range: 6 months–5 years). Surgical indications were: intermetatarsal angle (IMA) of 12–23°; increased proximal articular angle (PAA>8°), and range of motion of the metatarsophalangeal joint in flexion and extension >40°. Exclusion criteria were severe osteoporosis and/or osteoarthritis. The mean subjective range of motion (ROM) of the great toe post-surgery was 0.8±1.73 points (0: full ROM, 10: total stiffness). The mean subjective cosmetic result was 2.7±2.7 points (0: excellent, 10: poor). The overall post-operative patient satisfaction with the result was high (2.1±2.5 points (0: excellent, 10: poor). The mean hallux valgus angle improvement was 16.6° (pre-operative mean value: 37.5°) which was statistically significant (p<0.01). The IMA improved by an average of 5.96° from a pre-operative mean value of 15.4° (p<0.01). Neither osteonecrosis of the distal fragment nor perioperative fractures were noted during the follow-up. In keeping with our follow-up results, the Scarf osteotomy approach shows potential in the therapy of hallux valgus. PMID:21808668

  18. Effect of various hallux valgus reconstruction on sesamoid location: a radiographic study.

    PubMed

    Huang, Eddie H; Charlton, Timothy P; Ajayi, Samuel; Thordarson, David B

    2013-01-01

    The correction of sesamoid subluxation is an important component of hallux valgus reconstruction with some surgeons feeling that the sesamoids can be pulled back under the first metatarsal head when imbricating the medial capsule during surgery. The purpose of this study was to radiographically assess the effect of an osteotomy on sesamoid location relative to the second metatarsal. This is a retrospective radiographic study review of 165 patients with hallux valgus treated with reconstructive osteotomies. Patients were included if they underwent a scarf or basilar osteotomy for hallux valgus but were excluded if they had inflammatory arthropathy or lesser metatarsal osteotomy. A modified McBride soft tissue procedure was performed in conjunction with the basilar and scarf osteotomies. Each patient's preoperative and postoperative radiographs were evaluated for hallux valgus angle, intermetatarsal 1-2 angle, tibial sesamoid classification, and lateral sesamoid location relative to the second metatarsal. The greatest correction of both hallux valgus and intermetatrsal 1-2 angle was achieved in basilar osteotomies (20.6 degrees and 9.7 degrees, respectively), then scarf osteotomies (14.4 degrees and 8.7 degrees, respectively). Basilar and scarf osteotomies both corrected medial sesamoid subluxation relative to the first metatarsal head an average of 2-3 classification stages. All osteotomies had minimal lateral sesamoid location change relative to the second metatarsal. The majority of sesamoid correction correlated with the intermetatarsal 1-2 correction. The concept that medial capsular plication pulls the sesamoids beneath the first metatarsal (ie, changes the location of the sesamoids relative to the second metatarsal) was not supported by our results. Level III, retrospective case series.

  19. [The Akin procedure as closing wedge osteotomy for the correction of a hallux valgus interphalangeus deformity].

    PubMed

    Arnold, Heino

    2008-12-01

    Realignment of the great toe in the case of a hallux valgus interphalangeus by means of a medially based closing wedge osteotomy. Hallux valgus interphalangeus deformity, characterized by an enlarged distal articular surface angle (> 10 degrees). Correction of a hallux valgus interphalangeus deformity as an additional procedure in the case of hallux valgus surgery. Incongruent first metatarsophalangeal joint with lateral subluxation of the proximal phalanx. Isolated procedure to correct hallux valgus deformity. Lack of patient compliance. Neurovascular disturbance of the forefoot. Medially based closing wedge osteotomy of the proximal phalanx to reduce the distal articular surface angle. Fixation with a lag screw, cannulated Herbert screw, memory cramp, threaded Kirschner wire, or interosseous suture. Wound dressing to assure the position of the great toe. Radiographic documentation of the forefoot in two planes. Strict elevation of the operated foot to prevent postoperative swelling. Mobilization of the patient with a forefoot relief orthosis, until consolidation of the osteotomy is verified radiologically (4-5 weeks). Low-molecular-weight heparin for at least 1 week. Hallux valgus bandage or functional taping for 6 weeks postoperatively in patients with additional metatarsal osteotomy. Clinical and radiologic follow-up based on 32 patients showed good results. The postoperative Hallux Score of the American Orthopaedic Foot and Ankle Society improved to 89 points.

  20. Preoperative varus-valgus kinematic pattern throughout flexion persists more strongly after cruciate-retaining than after posterior-stabilized total knee arthroplasty.

    PubMed

    Hino, Kazunori; Oonishi, Yoshio; Kutsuna, Tatsuhiko; Watamori, Kunihiko; Iseki, Yasutake; Kiyomatsu, Hiroshi; Watanabe, Seiji; Miura, Hiromasa

    2016-08-01

    Restoration of normal knee kinematics is key to improving patient satisfaction and functional outcomes after total knee arthroplasty (TKA). However, the effect of preoperative varus-valgus kinematics due to knee osteoarthritis on the postoperative kinematics is unclear. The function of the knee ligament contributes to both knee stability and kinematics. The aim of this study was to evaluate changes in varus-valgus kinematics before and after TKA using a navigation system, in addition to comparing the pre- and postoperative changes in kinematic patterns between cruciate-retaining (CR)- and posterior-stabilized (PS)-TKAs. Forty knees treated with TKA were evaluated (CR-TKA 20; PS-TKA 20). Manual mild passive knee flexion was applied while moving the leg from full extension to flexion. The varus-valgus angle was automatically measured by a navigation system at every 10° of the flexion angle, and the kinematics were evaluated. Kinematic patterns throughout flexion can be classified into five types. The pre- and postoperative kinematic patterns were similar in 60% of patients who underwent CR-TKA, whereas they were similar in only 25% of those who underwent PS-TKA. The mean change in the size of the varus-valgus angle throughout flexion did not differ between CR-TKA and PS-TKA. However, the distribution of changes in the size of the varus-valgus angle differed between CR-TKA and PS-TKA. We obtained the following results: 1) some patterns of varus-valgus kinematics are noted under unloading conditions despite recovery of neutral alignment in extension and 2) the preoperative varus-valgus kinematic pattern persisted more strongly after CR-TKA than after PS-TKA. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Hallux valgus correction using transarticular lateral release with distal chevron osteotomy.

    PubMed

    Choi, Young Rak; Lee, Ho Seong; Jeong, Jae Jung; Kim, Sang Woo; Jeon, In-Ho; Lee, Dong Ho; Lee, Woo Chun

    2012-10-01

    Transarticular lateral release through a medial incision can avoid a dorsal incision. This study investigated outcomes following hallux valgus correction using transarticular lateral release, distal chevron metatarsal osteotomy and Akin phalangeal osteotomy through one medial incision. Between June 2004 and May 2009, a single surgeon performed a transarticular lateral release, distal chevron metatarsal osteotomy and Akin phalangeal osteotomy through one medial incision for hallux valgus on a total of 103 feet of 68 patients. The average patient age at the time of surgery was 51 years, and the average followup was 27 months. The average preoperative and final followup results were: 1) hallux valgus angle improvement from 29 degrees to 5 degrees, 2) intermetatarsal angle from 13 degrees to 5 degrees and 3) medial sesamoid bone position from 3 to 1 (p < 0.05 for each variable). The average AOFAS scores were improved from 49 to 92, and the VAS pain scores were improved from 7 to 1 (p < 0.05 for both variables). No patient had a serious complication such as infection, avascular necrosis, nonunion, transfer-metatarsalgia, or first metatarsophalangeal joint arthritis. Hallux valgus correction using transarticular lateral release, distal chevron metatarsal osteotomy and Akin phalangeal osteotomy through one medial incision was found to be effective and safe. The advantages include that the procedure is simple, early ambulation is possible, and there is no dorsal scarring.

  2. [Distal osteotomy for the treatment of hallux valgus (Chevron osteotomy)].

    PubMed

    Stukenborg-Colsman, C; Claaßen, L; Ettinger, S; Yao, D; Lerch, M; Plaaß, C

    2017-05-01

    Distal osteotomies, like the Chevron osteotomy, is indicated for mild to moderate hallux valgus deformities. Splayfoot, painful pseudoexostosis, and transfer metatasalgia are observed in the clinical examination. Radiographic examination should be done with weight bearing in two planes. Preoperatively the intermetatarsal (IM), hallux valgus, and distal metatarsal articular (DMAA) angles should be measured. The operative technique is based on soft tissue and bony correction. Modifications of the osteotomy allow a shortening, lengthening, or neutral correction of the first metatarsal. With a modified Chevron osteotomy, an increased DMAA can be also corrected.

  3. New modified technique of osteotomy for hallux valgus.

    PubMed

    Oh, I S; Kim, M K; Lee, S H

    2004-12-01

    To improve the technique of osteotomy for hallux valgus (bunion). 38 cases of a new modified osteotomy procedure for hallux valgus were performed for 22 patients (21 women and one man). During a 3-year (range, 2-5 years) follow-up, the patients underwent physical examination; and their American Orthopedic Foot and Ankle Society hallux-metatarso-phalangeal-interphalangeal scale scores and standard foot radiographic measurements were recorded. 20 of the 22 patients (38 cases) had no pain, achieved good cosmesis, and were completely satisfied with the results of the operation. The remaining 2 patients had occasional mild discomfort. The mean hallux-metatarso-phalangeal-interphalangeal scale score was 93 points (range, 78-100 points). The mean preoperative and postoperative metatarsophalangeal angles were 34 degrees and 11 degrees, respectively. The mean postoperative reduction of the intermetatarsal angle and metatarsophalangeal angle were 6 degrees and 23 degrees, respectively. The new technique of osteotomy achieved even greater stability and accurate correction of the deformity in our 38 cases. Furthermore, it was more effective than conventional 'chevron' osteotomy in terms of correction of the deformity. Therefore, it should be used more widely.

  4. Outcomes in chevron osteotomy for Hallux Valgus in a large cohort.

    PubMed

    van Groningen, Bart; van der Steen, M C Marieke; Reijman, Max; Bos, Janneke; Hendriks, Johannes G E

    2016-12-01

    Clinical and radiological related outcomes have been reported for Chevron osteotomy as correction for mild to moderate hallux valgus, but only for relatively small patient series. Moreover, evaluation of the patient's point of view has mostly been conducted by means of more physician-based outcome measures. The goal of this study was to evaluate the effect of the Chevron osteotomy for hallux valgus on patients' daily lives using the Foot and Ankle Outcome Score (FAOS) as a validated and a hallux valgus specific patient reported outcome measure (PROM). Secondary outcome measures were radiological correction, complication rate, and re-operations. All 438 Chevron procedures (336 patients), at two surgical hospital sites in the period between January 2010 and October 2014, were retrospectively evaluated with a follow-up of at least 6 months. Patients were invited to fill in a cross-sectional online FAOS. For the FAOS, a total response of 60% was achieved. The FAOS ranged between 71 and 88 with a follow-up of on average 36 months. Patients with an undercorrection of their hallux valgus (11.6% of the procedures) scored significantly lower on three subscales of the FAOS (range between 61 and 77 versus 72-84). Patients who had a reoperation (12.6% of the procedures) also scored significantly lower on four subscales: 58-100 versus 73-89. Postoperative radiological measurements improved significantly with a mean difference of 6.1 (5.9; 6.4) degrees for the intermetatarsal angle and 13.7 (13.0; 14.5) degrees for the hallux valgus angle. In this large study cohort, Chevron osteotomy for hallux valgus offers good PROM scores on FAOS. These scores were significantly lower in patients with radiological undercorrection or with a reoperation. Results of the FAOS appear to modulate with physician based outcomes and therapeutic incidents. Improvement of outcome may therefore well be possible by increased attention on these surgical details. Copyright © 2016 Elsevier Ltd. All rights

  5. Clinical ratings and plasma HVA during cocaine abstinence.

    PubMed

    Martin, S D; Yeragani, V K; Lodhi, R; Galloway, M P

    1989-08-01

    Six patients were evaluated over a 21-day period during inpatient recovery from chronic repeated cocaine use. Serial evaluations of Hamilton depression rating, cocaine craving, plasma homovanillic acid (pHVA), and plasma 3-methoxy-4-hydroxyphenylethyleneglycol (pMHPG) concentrations were determined. There was a distinct increase in cocaine craving between 1 and 2 weeks after the last cocaine use. Levels of pHVA also increased at the time of heightened craving. The data provide preliminary evidence to suggest that changes in cocaine craving during abstinence are positively correlated with changes in dopamine turnover.

  6. [Total knee arthroplasty by lateral parapatellar approach for valgus knee].

    PubMed

    Zhou, Dian-ge; Zhang, Bin; Kou, Bo-long; Lü, Hou-shan

    2007-07-17

    To investigate the effect of lateral parapatellar approach in total knee arthroplasty (TKA) of valgus knee. Lateral parapatellar approach of total knee arthroplasty was applied in 8 patients (10 knees) with severe valgus osteoarthritis knee (bilateral in 2 cases and unilateral in 6 cases), with the valgus angle > 15 degrees , 1 male (1 knee) and 7 females (9 knee), aged 68.2 (58 - 79), 7 cases (9 knees) being of the Krackow type I and 1 case (1 knee) of the Krackow type I, I. After incision of the skin through lateral knee, ilio-tibial band was prolonged by apple pie arthroplasty. The joint capsule was cut open laterally 2 - 4 cm from the para-patellar edge. Soft tissue balance was performed by releasing I - T band in Gerdy tubercle, lateral collateral ligament and poster-lateral capsule from the femur and tibial side. Valgus angle of distal femur cutting were five degree. Whiteside line and trans-epicondylar line were used as AP rotational cutting reference. All patellar of the group were resurfaced. Capsule closure is completed with the knee flexed. The expanded deep lateral soft tissue sleeve (coronal Z-plasty) is sutured with the medial retinaculum sleeve (superficial layer). Follow-up was conducted for 19.6 months (1 - 51 months). Seven cases (9 knees) were replaced by posterior stabilized cemented prostheses (TC-Dynamic, PLUS), one case (1 knee) was replaced by RT prosthesis (RT-PLUS(TM) Solution, PLUS). After operation, the valgus deformity of all patients was corrected and all patients could walk 100 m with or without the help of walking holders. The average range of motion (ROM) was improved from the pre-operative. 95.6 degrees (85 degrees - 110 degrees ) to the post-operative 117.1 degrees (100 degrees - 125 degrees ). The average femorotibial angle (FTA) was corrected from the pre-operative. 27.6 degrees (20 degrees - 40 degrees ) to the post-operative 6.8 degrees (5 degrees - 9 degrees ). The Knee Score System (KSS) score and functional score were

  7. The "moving valgus stress test" for medial collateral ligament tears of the elbow.

    PubMed

    O'Driscoll, Shawn W M; Lawton, Richard L; Smith, Adam M

    2005-02-01

    The diagnosis of a painful partial tear of the medial collateral ligament in overhead-throwing athletes is challenging, even for experienced elbow surgeons and despite the use of sophisticated imaging techniques. The "moving valgus stress test" is an accurate physical examination technique for diagnosis of medial collateral ligament attenuation in the elbow. Cohort study (diagnosis); Level of evidence, 2. Twenty-one patients underwent surgical intervention for medial elbow pain due to medial collateral ligament insufficiency or other abnormality of chronic valgus overload, and they were assessed preoperatively with an examination called the moving valgus stress test. To perform the moving valgus stress test, the examiner applies and maintains a constant moderate valgus torque to the fully flexed elbow and then quickly extends the elbow. The test is positive if the medial elbow pain is reproduced at the medial collateral ligament and is at maximum between 120 degrees and 70 degrees. The moving valgus stress test was highly sensitive (100%, 17 of 17 patients) and specific (75%, 3 of 4 patients) when compared to assessment of the medial collateral ligament by surgical exploration or arthroscopic valgus stress testing. The mean shear range (ie, the arc within which pain was produced with the moving valgus stress test) was 120 degrees to 70 degrees. The mean angle at which pain was at a maximum was 90 degrees of elbow flexion. The moving valgus stress test is an accurate physical examination technique that, when performed and interpreted correctly, is highly sensitive for medial elbow pain arising from the medial collateral ligament.

  8. Distal chevron osteotomy with distal soft tissue procedure for moderate to severe hallux valgus deformity.

    PubMed

    Bai, Long Bin; Lee, Keun Bae; Seo, Chang Young; Song, Eun Kyoo; Yoon, Taek Rim

    2010-08-01

    Distal chevron osteotomy has been widely employed to treat mild to moderate hallux valgus deformity. The purpose of the present study was to evaluate the outcomes of distal chevron osteotomy with a distal soft tissue procedure for the correction of moderate to severe hallux valgus. We reviewed 76 patients (86 feet) that underwent distal chevron osteotomy with a distal soft tissue procedure for symptomatic moderate to severe hallux valgus deformity. At a mean followup of 31 months, all patients were evaluated using subjective, objective and radiographic measurements. Ninety-four percent of the patients were very satisfied or satisfied. Average AOFAS score improved from 54.7 points preoperatively to 92.9 at final followup. Average hallux valgus angle changed from 36.2 degrees preoperatively to 12.4 degrees at final followup, and average first-second intermetatarsal angle changed from 17.1 to 7.3 degrees. Average tibial sesamoid position changed from 2.4 preoperatively to 1.2 at final followup. Dorsal angulation of the head was observed in two feet, and plantaflexion of the head in four feet. There were no cases of avascular necrosis of the metatarsal head. Our results indicate that distal chevron osteotomy with a distal soft tissue procedure provides an effective and reliable means of correcting moderate to severe hallux valgus deformity, and that it does so with high levels of patient satisfaction and low incidence of complications.

  9. The effect of isolated valgus moments on ACL strain during single-leg landing: A simulation study

    PubMed Central

    Shin, Choongsoo S.; Chaudhari, Ajit M.; Andriacchi, Thomas P.

    2009-01-01

    Valgus moments on the knee joint during single-leg landing have been suggested as a risk factor for anterior cruciate ligament (ACL) injury. The purpose of this study was to test the influence of isolated valgus moment on ACL strain during single-leg landing. Physiologic levels of valgus moments from an in vivo study of single-leg landing were applied to a three-dimensional dynamic knee model, previously developed and tested for ACL strain measurement during simulated landing. The ACL strain, knee valgus angle, tibial rotation, and medial collateral ligament (MCL) strain were calculated and analyzed. The study shows that the peak ACL strain increased nonlinearly with increasing peak valgus moment. Subjects with naturally high valgus moments showed greater sensitivity for increased ACL strain with increased valgus moment, but ACL strain plateaus below reported ACL failure levels when the applied isolated valgus moment rises above the maximum values observed during normal cutting activities. In addition, the tibia was observed to rotate externally as the peak valgus moment increased due to bony and soft-tissue constraints. In conclusion, knee valgus moment increases peak ACL strain during single-leg landing. However, valgus moment alone may not be sufficient to induce an isolated ACL tear without concomitant damage to the MCL, because coupled tibial external rotation and increasing strain in the MCL prevent proportional increases in ACL strain at higher levels of valgus moment. Training that reduces the external valgus moment, however, can reduce the ACL strain and thus may help athletes reduce their overall ACL injury risk. PMID:19100550

  10. Evolution of plasma homovanillic acid (HVA) levels during treatment in schizo-affective disorder.

    PubMed

    Galinowski, A; Castelnau, C; Spreux-Varoquaux, O; Bourdel, M C; Olie, J P; Loo, H; Poirier, M F

    2000-11-01

    1. Plasma Homovanillic Acid (p HVA) levels were measured by HPLC (high performance liquid chromatography) in 5 schizo-affective depressed patients receiving a standardized treatment. (lithium, chlorpromazine and clomipramine) during 4 weeks. 2. Four patients were pretreated, without a washout period. 3. No significant difference was observed between patients and normal controls at baseline. Under treatment, pHVA levels increased (p<0.02) with clinical improvement (MADRS and PANSS scores). 4. Although effects of medications prior to the study period were not controlled, these findings suggest that depressed schizo-affective patients may have normal pHVA levels that increase with clinical improvement, unlike schizophrenic patients whose increased pHVA concentrations decline with neuroleptic treatment.

  11. Preliminary Results and Learning Curve of the Minimally Invasive Chevron Akin Operation for Hallux Valgus.

    PubMed

    Jowett, Charlie R J; Bedi, Harvinder S

    Minimally invasive surgery is increasing in popularity. It is relevant in hallux valgus surgery owing to the potential for reduced disruption of the soft tissues and improved wound healing. We present our results and assess the learning curve of the minimally invasive Chevron Akin operation for hallux valgus. A total of 120 consecutive feet underwent minimally invasive Chevron Akin for symptomatic hallux valgus, of which 14 were excluded. They were followed up for a mean of 25 (range 18 to 38) months. The patients were clinically assessed using the American Orthopaedic Foot and Ankle Society score. Complications and patient satisfaction were recorded. The radiographs were analyzed and measurements recorded for hallux valgus and intermetatarsal angle correction. The mean age of the patients undergoing surgery was 55 (range 25 to 81) years. Of the 78 patients, 76 (97.4%) were female and 2 (2.6%) were male; 28 (35.9%) cases were bilateral. The mean American Orthopaedic Foot and Ankle Society score improved from 56 (range 23 to 76) preoperatively to 87 (range 50 to 100) postoperatively (p < .001). The mean hallux valgus and intermetatarsal angles preoperatively were 29.7° (range 12° to 46°) and 14.0° (range 8° to 20°). The corresponding postoperative angles were 10.3° (range 0° to 25°) and 7.6° (range 3° to 15°; p < .001). The patients were satisfied with the results of surgery in 87% of cases (92 of 106). The incidence of reoperation was 14% (15 of 106). These are the only reported results for this technique. They display a steep associated learning curve. However, the results are promising, and the learning curve is comparable to that for open hallux valgus surgery. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  12. Plasma HVA levels following debrisoquine administration do not reflect cerebral dopamine loss in early Parkinson's disease.

    PubMed

    Rose, S; Hindmarsh, J G; Steiger, M J; Bhatt, M; Quinn, N P; Jenner, P; Marsden, C D

    1994-06-01

    Plasma levels of homovanillic acid (pHVA) following debrisoquine (DBQ) administration may be indicative of central dopaminergic activity. The effect of DBQ (10-20 mg) administration on pHVA in young healthy volunteers was studied to establish a protocol for use in de novo patients with Parkinson's disease. Subsequently, pHVA in de novo patients with Parkinson's disease were measured and compared to young healthy volunteers. Following DBQ (10 mg) administration to healthy volunteers, pHVA fell with time to a maximum of 62% of control values at 6 h. The decrease in pHVA was not affected by loading with DBQ (10 mg) 10 h previously (pHVA: 67.6 +/- 5.8% of preDBQ levels) or increasing the dose to 20 mg (56.1 +/- 11.8% of preDBQ levels) compared to a single 10 mg dose of debrisoquine (66.5 +/- 4.5% of preDBQ levels). pHVA was reduced in both de novo patients with Parkinson's disease and in healthy volunteers following DBQ (10 mg) administration. However, there was no difference in pHVA before or after DBQ administration when comparing the two groups. These results suggest that, following DBQ administration, pHVA does not reflect dopamine neuronal loss in de novo patients with Parkinson's disease, so it is unlikely to detect the disease before the clinical symptoms manifest themselves.

  13. No midterm benefit from low intensity pulsed ultrasound after chevron osteotomy for hallux valgus.

    PubMed

    Zacherl, Max; Gruber, Gerald; Radl, Roman; Rehak, Peter H; Windhager, Reinhard

    2009-08-01

    Chevron osteotomy is a widely accepted method for correction of symptomatic hallux valgus deformity. Full weight bearing in regular shoes is not recommended before 6 weeks after surgery. Low intensity pulsed ultrasound is known to stimulate bone formation leading to more stable callus and faster bony fusion. We performed a randomized, placebo-controlled, double-blinded study on 44 participants (52 feet) who underwent chevron osteotomy to evaluate the influence of daily transcutaneous low intensity pulsed ultrasound (LIPUS) treatment at the site of osteotomy. Follow-up at 6 weeks and 1 year included plain dorsoplantar radiographs, hallux-metatarsophalangeal-interphalangeal scale and a questionnaire on patient satisfaction. There was no statistical difference in any pre- or postoperative clinical features, patient satisfaction or radiographic measurements (hallux valgus angle, intermetatarsal angle, sesamoid index and metatarsal index) except for the first distal metatarsal articular angle (DMAA). The DMAA showed statistically significant (p = 0.046) relapse in the placebo group upon comparison of intraoperative radiographs after correction and fixation (5.2 degrees) and at the 6-week follow-up (10.6 degrees). Despite potential impact of LIPUS on bone formation, we found no evidence of an influence on outcome 6 weeks and 1 year after chevron osteotomy for correction of hallux valgus deformity.

  14. Extended plantar limb (modified) chevron osteotomy versus scarf osteotomy for hallux valgus correction: A randomised controlled trial.

    PubMed

    Mahadevan, Devendra; Lines, Stephen; Hepple, Stephen; Winson, Ian; Harries, William

    2016-06-01

    The purpose of this RCT was to compare the extended plantar limb (modified) chevron osteotomy with the scarf osteotomy in correcting hallux valgus deformity and improving functional scores and patient satisfaction. Patients were randomly assigned and kept blind to surgical allocation. Cases requiring additional procedures including the Akin osteotomy were excluded. Outcomes were measured at 1 year following surgery. 84 patients (109 feet) were analysed (60 modified chevron; 49 Scarf). The mean age was 50.7 years (75F: 9M). Post-operative intermetatarsal angle (IMA) was significantly lower in the modified chevron group (5.8° versus 6.9°, p=0.045). Hallux valgus angle and distal metatarsal articular angle were similar. The magnitude of IMA correction with the modified chevron was also significantly greater (9.1° versus 7.1°, p=0.007). Both osteotomies produced comparable MOxFQ scores and satisfaction ratings. The modified chevron was superior to the scarf osteotomy in correcting IMA in hallux valgus deformity. Copyright © 2015 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  15. Clinical outcome after Chevron-Akin double osteotomy versus isolated Chevron procedure: a prospective matched group analysis.

    PubMed

    Lechler, Philipp; Feldmann, Christine; Köck, Franz Xaver; Schaumburger, Jens; Grifka, Joachim; Handel, Martin

    2012-01-01

    Hallux valgus is a frequent condition of the forefoot, resulting in cosmetic deformity and pain. Chevron osteotomy (CO) is widely employed for the treatment of hallux valgus. Chevron-Akin double osteotomy (CAO) was previously described and superiority over an isolated Chevron procedure was assumed. The objective of this study was to compare the short-to-middle term outcomes of CO and CAO. This study included 72 patients with established diagnosis of mild-to-moderate hallux valgus, treated by either isolated CO or CAO. The CO group included 46 patients (mean 51.5 years) with a mean hallux valgus angle of 27°, while the CAO group included 26 subjects (mean 53.1 years) and a mean hallux valgus angle of 32° preoperatively. All patients were reviewed by physical examination, and standardized questionnaire, and pre- and postoperative standing X-rays were performed. Matched group analysis was carried out to analyze statistical differences of both techniques. The patients were assessed and group matched at a mean of 1.37 years for the CO group and 1.04 years for the CAO group, postoperatively. Mean improvement of HVA (hallux valgus angle) was 10.6° in the CO group and the CAO group improved by 17.5°. DMAA (distal metatarsal articular angle) improved in the CO group by 5.4° and in the CAO by 13.7°. Mean AOFAS score improved by 27.9 (CO) and 21.5 (CAO). Patient satisfaction was high in both groups, with a tendency towards higher values within the CAO group. These findings indicate that Chevron-Akin double osteotomy is a save and practicable procedure for the treatment of mild-to-moderate hallux valgus. Superiority of combined Chevron-Akin procedure over an isolated Chevron osteotomy might be limited to distinct clinical settings, but should not be generally assumed.

  16. Comparison of Clinical Outcomes of Scarf and Chevron Osteotomies and the McBride Procedure in the Treatment of Hallux Valgus Deformity

    PubMed Central

    Fakoor, Mohammad; Sarafan, Naser; Mohammadhoseini, Payam; Khorami, Mohsen; Arti, Hamidreza; Mosavi, SeyedShahnam; Aghaeeaghdam, Amir

    2014-01-01

    Background: Hallux valgus deformity is a common chronic problem with a reported prevalence of 28.4% and its chief complaint is pain. Thus far, different surgical procedures with their proposed indications have been introduced. This study compared three current procedures, namely the chevron and scarf osteotomies and the McBride procedure. Methods: This retrospective cohort was conducted at the Ahvaz University of Medical Sciences on 44 patients with moderate hallux valgus deformity from 2010 and 2013. All of the patients underwent one of the three procedures (chevron, scarf or McBride). Preoperative and follow up radiographies were evaluated in terms of hallux valgus and intermetatarsal angle correction. The Foot and Ankle Disability Index was filled out to assess the functional outcome and the Visual Analogue Scale was used to evaluate pain. Also, satisfaction, aesthetics and the rate of recurrence was evaluated. Results: Hallux valgus angle and intermetatarsal angle correction were significantly higher in scarf, but not in chevron and McBride. However, from amongst the three procedures, there was no significant difference in terms of the Foot and Ankle Disability Index score, aesthetics, satisfaction level, pain score and recurrence rate. Conclusions: Considering that scarf osteotomy had better results in this study, we think that scarf osteotomy can be considered as a first choice for the treatment of moderate hallux valgus deformity. PMID:25207310

  17. Comparison of Clinical Outcomes of Scarf and Chevron Osteotomies and the McBride Procedure in the Treatment of Hallux Valgus Deformity.

    PubMed

    Fakoor, Mohammad; Sarafan, Naser; Mohammadhoseini, Payam; Khorami, Mohsen; Arti, Hamidreza; Mosavi, SeyedShahnam; Aghaeeaghdam, Amir

    2014-03-01

    Hallux valgus deformity is a common chronic problem with a reported prevalence of 28.4% and its chief complaint is pain. Thus far, different surgical procedures with their proposed indications have been introduced. This study compared three current procedures, namely the chevron and scarf osteotomies and the McBride procedure. This retrospective cohort was conducted at the Ahvaz University of Medical Sciences on 44 patients with moderate hallux valgus deformity from 2010 and 2013. All of the patients underwent one of the three procedures (chevron, scarf or McBride). Preoperative and follow up radiographies were evaluated in terms of hallux valgus and intermetatarsal angle correction. The Foot and Ankle Disability Index was filled out to assess the functional outcome and the Visual Analogue Scale was used to evaluate pain. Also, satisfaction, aesthetics and the rate of recurrence was evaluated. Hallux valgus angle and intermetatarsal angle correction were significantly higher in scarf, but not in chevron and McBride. However, from amongst the three procedures, there was no significant difference in terms of the Foot and Ankle Disability Index score, aesthetics, satisfaction level, pain score and recurrence rate. Considering that scarf osteotomy had better results in this study, we think that scarf osteotomy can be considered as a first choice for the treatment of moderate hallux valgus deformity.

  18. [A special soft tissue procedure for treatment of hallux valgus].

    PubMed

    Waizy, H; Stukenborg-Colsman, C; Abbara-Czardybon, M; Emmerich, J; Windhagen, H; Frank, D

    2011-02-01

    Maintaining the corrected position of the first metatasophalangeal axis. Reducing postoperative stiffness by forgoing a medial capsular shift. Hallux valgus deformities or recurrent hallux valgus deformities. Existing osteoarthritis, joint stiffness, large bone defects, osteonecrosis. General medical contraindications to surgical interventions and anesthesiological procedures. Operation under regional anesthesia (foot block) or general anesthesia. Tourniquet. Longitudinal skin incision medial over the pseudexostosis of the first metatarsal bone. Preparing the tendon of the Musculus abductor hallucis. Detaching the tendon from the capsule. Incision of the joint capsule with protection of the extensor hallucis longus tendon and the dorsal neurovascular bundle in an L-wise manner. Osteotomy of the first metatarsal bone. Lax sutures of the capsule in correct position and reattachment of the Musculus abductor hallucis tendon shifted toward distal and dorsal, regarding the rotation of the hallux. Postoperative elevation of the operated foot. Analgesia with nonsteroidal antiinflammatory drugs. Postoperative weight-bearing according to the osteotomy. Passive mobilization of the metatarsophalangeal joint. Dressing for 4 weeks postoperatively in the corrected position. Radiologic control after 6 weeks. Hallux valgus orthosis at night and a toe spreader for a further 6 weeks. A total of 30 isolated hallux valgus deformities with a mean preoperative intermetatarsal (IMA) angle of 12.9° (range 11-15°) were operated with a chevron osteotomy. The mean follow-up was 14.4 (range 8-17) months. The mean dorsiflexion at the last follow-up was 44° (range 20-60°). Only 2 patients had a dorsiflexion <40°. The mean reduction of the IM angle was 5.6° (range 3-7°). One patient required wound revision. There was no infection or avascular necrosis of the metatarsal head observed in the patients. At follow-up, 20 (67%) patients were completely satisfied, 9 (30%) satisfied, and 1 (3

  19. A modified Austin/chevron osteotomy for treatment of hallux valgus and hallux rigidus.

    PubMed

    Vasso, Michele; Del Regno, Chiara; D'Amelio, Antonio; Schiavone Panni, Alfredo

    2016-03-01

    The purpose of this brief paper is to present the preliminary results of a modified Austin/chevron osteotomy for treatment of hallux valgus and hallux rigidus. In this procedure, the dorsal arm of the osteotomy is performed orthogonal to the horizontal plane of the first metatarsal, the main advantage being that this allows much easier and more accurate multiplanar correction of first metatarsal deformities. From 2010 to 2013, 184 consecutive patients with symptomatic hallux valgus and 48 patients with hallux rigidus without severe metatarsophalangeal joint degeneration underwent such modified chevron osteotomy. Mean patient age was 54.9 (range 21-70) years, and mean follow-up duration was 41.7 (range 24-56) months. Ninety-three percent of patients were satisfied with the surgery. Mean American Orthopaedic Foot and Ankle Society (AOFAS) score improved from 56.6 preoperatively to 90.6 at last follow-up, and mean visual analog scale (VAS) pain score decreased from 5.7 preoperatively to 1.6 at final follow-up (p < 0.05). In patients treated for hallux valgus, mean hallux valgus angle decreased from 34.1° preoperatively to 6.2° at final follow-up, and mean intermetatarsal angle decreased from 18.5° preoperatively to 4.1° at final follow-up (p < 0.05). One patient developed postoperative transfer metatarsalgia, treated successfully with second-time percutaneous osteotomy of the minor metatarsals, whilst one patient had wound infection that resolved with systemic antibiotics. Level IV.

  20. [A cadaveric study of a new capsulorrhaphy for the surgical treatment of hallux valgus].

    PubMed

    Orozco-Villaseñor, S L; Monzó-Planella, M; Martín-Oliva, X; Vázquez-Escamilla, J; Mayagoitia-Vázquez, J J; Frías-Chimal, J E

    2017-01-01

    There are many surgical options for the treatment of hallux valgus in combination with capsular repairs for the correction of hallux valgus. This report corresponds to a descriptive study where a new capsulorrhaphy technique in hallux valgus is proposed. Six dissections were performed on cadavers with hallux valgus deformity using the following surgical technique: medial approach on the first toe longitudinally, dissecting by planes and locating the metatarsophalangeal joint capsule; it was incised longitudinally. The capsule was separated and an exostectomy of the first metatarsal head was done, the edges were regularized and a release of the abductor hallucis was performed. Later, the capsular remnant was resected and repaired. Six cadaveric feet with hallux valgus were studied, five with mild deformity, one with moderate deformity, one foot with the 2nd finger on supraductus. Many capsular repairs have been reported in the literature, including «L», triangular, «V-Y», rectangular, with satisfactory results, along with osteotomy of the first metatarsal. In this report, a new capsular repair was described. Applying this new capsular repair, we reduced the metatarsophalangeal and intermetatarsal angles and achieved a capsular closure with suitable tension; the metatarsophalangeal joint mobility was preserved.

  1. Ninety-Degree Chevron Osteotomy for Correction of Hallux Valgus Deformity: Clinical Data and Finite Element Analysis

    PubMed Central

    Matzaroglou, Charalambos; Bougas, Panagiotis; Panagiotopoulos, Elias; Saridis, Alkis; Karanikolas, Menelaos; Kouzoudis, Dimitris

    2010-01-01

    Hallux valgus is a very common foot disorder, with its prevalence estimated at 33% in adult shoe-wearing populations. Conservative management is the initial treatment of choice for this condition, but surgery is sometimes needed. The 600 angle Chevron osteotomy is an accepted method for correction of mild to moderate hallux valgus in adults less than 60 years old. A modified 900 angle Chevron osteotomy has also been described; this modified technique can confer some advantages compared to the 600 angle method, and reported results are good. In the current work we present clinical data from a cohort of fifty-one female patients who had surgery for sixty-two hallux valgus deformities. In addition, in order to get a better physical insight and study the mechanical stresses along the two osteotomies, Finite Element Analysis (FEA) was also conducted. FEA indicated enhanced mechanical bonding with the modified 900 Chevron osteotomy, because the compressive stresses that keep the two bone parts together are stronger, and the shearing stresses that tend to slide the two bone parts apart are weaker, compared to the typical 600 technique. Follow-up data on our patient cohort show good or excellent long-term clinical results with the modified 900 angle technique. These results are consistent with the FEA-based hypothesis that a 900 Chevron osteotomy confers certain mechanical advantages compared to the typical 600 procedure. PMID:20648223

  2. Minimally Invasive and Open Distal Chevron Osteotomy for Mild to Moderate Hallux Valgus.

    PubMed

    Brogan, Kit; Lindisfarne, Edward; Akehurst, Harold; Farook, Usama; Shrier, Will; Palmer, Simon

    2016-11-01

    Minimally invasive surgical (MIS) techniques are increasingly being used in foot and ankle surgery but it is important that they are adopted only once they have been shown to be equivalent or superior to open techniques. We believe that the main advantages of MIS are found in the early postoperative period, but in order to adopt it as a technique longer-term studies are required. The aim of this study was to compare the 2-year outcomes of a third-generation MIS distal chevron osteotomy with a comparable traditional open distal chevron osteotomy for mild-moderate hallux valgus. Our null hypothesis was that the 2 techniques would yield equivalent clinical and radiographic results at 2 years. This was a retrospective cohort study. Eighty-one consecutive feet (49 MIS and 32 open distal chevron osteotomies) were followed up for a minimum 24 months (range 24-58). All patients were clinically assessed using the Manchester-Oxford Foot Questionnaire. Radiographic measures included hallux valgus angle, the intermetatarsal angle, hallux interphalangeal angle, metatarsal phalangeal joint angle, distal metatarsal articular angle, tibial sesamoid position, shape of the first metatarsal head, and plantar offset. Statistical analysis was done using Student t test or Wilcoxon rank-sum test for continuous data and Pearson chi-square test for categorical data. Clinical and radiologic postoperative scores in all domains were substantially improved in both groups (P < .001), but there was no statistically significant difference in improvement of any domain between open and MIS groups (P > .05). There were no significant differences in complications between the 2 groups ( > .5). The midterm results of this third-generation technique show that it was a safe procedure with good clinical outcomes and comparable to traditional open techniques for symptomatic mild-moderate hallux valgus. Level III, retrospective comparative study. © The Author(s) 2016.

  3. Injury tolerance and moment response of the knee joint to combined valgus bending and shear loading.

    PubMed

    Bose, Dipan; Bhalla, Kavi S; Untaroiu, Costin D; Ivarsson, B Johan; Crandall, Jeff R; Hurwitz, Shepard

    2008-06-01

    Valgus bending and shearing of the knee have been identified as primary mechanisms of injuries in a lateral loading environment applicable to pedestrian-car collisions. Previous studies have reported on the structural response of the knee joint to pure valgus bending and lateral shearing, as well as the estimated injury thresholds for the knee bending angle and shear displacement based on experimental tests. However, epidemiological studies indicate that most knee injuries are due to the combined effects of bending and shear loading. Therefore, characterization of knee stiffness for combined loading and the associated injury tolerances is necessary for developing vehicle countermeasures to mitigate pedestrian injuries. Isolated knee joint specimens (n=40) from postmortem human subjects were tested in valgus bending at a loading rate representative of a pedestrian-car impact. The effect of lateral shear force combined with the bending moment on the stiffness response and the injury tolerances of the knee was concurrently evaluated. In addition to the knee moment-angle response, the bending angle and shear displacement corresponding to the first instance of primary ligament failure were determined in each test. The failure displacements were subsequently used to estimate an injury threshold function based on a simplified analytical model of the knee. The validity of the determined injury threshold function was subsequently verified using a finite element model. Post-test necropsy of the knees indicated medial collateral ligament injury consistent with the clinical injuries observed in pedestrian victims. The moment-angle response in valgus bending was determined at quasistatic and dynamic loading rates and compared to previously published test data. The peak bending moment values scaled to an average adult male showed no significant change with variation in the superimposed shear load. An injury threshold function for the knee in terms of bending angle and shear

  4. Plasma HVA, tardive dyskinesia and psychotic symptoms in long-term drug-free inpatients with schizophrenia.

    PubMed

    Muscettola, G; Barbato, G; de Bartolomeis, A; Monteleone, P; Pickar, D

    1990-09-01

    Plasma homovanillic acid (pHVA) levels were measured in 16 chronically ill patients with schizophrenia who also suffered from tardive dyskinesia, and in a group of 14 chronically ill patients with schizophrenia who did not have tardive dyskinesia. All patients were studied following an extensive drug-free period (mean = 32.9 months). Patients with orofacial dyskinesia had significantly lower levels of pHVA than did controls. In patients without tardive dyskinesia, pHVA levels were significantly correlated with both positive and negative symptomatology. In contrast, pHVA levels from patients with tardive dyskinesia bore neither a significant nor a nearly significant relationship to symptomatology. The implications of these findings for dopaminergic models of tardive dyskinesia are discussed.

  5. Tibiofemoral Osteoarthritis and Varus-Valgus Laxity

    PubMed Central

    Freisinger, Gregory M.; Schmitt, Laura C.; Wanamaker, Andrea B.; Siston, Robert A.; Chaudhari, Ajit M. W.

    2017-01-01

    The purpose of this study was to systematically review and synthesize the literature measuring varus-valgus laxity in individuals with tibiofemoral osteoarthritis (OA). Specifically, we aimed to identify varus-valgus laxity differences between persons with OA and controls, by radiographic disease severity, by frontal plane knee alignment, and by sex. We also aimed to identify if there was a relationship between varus-valgus laxity and clinical performance and self-reported function. We systematically searched for peer-reviewed original research articles in PubMed, Scopus, and CINAHL to identify all existing literature regarding knee OA and objective measurement of varus-valgus laxity in vivo. Forty articles were identified that met the inclusion criteria and data were extracted. Varus-valgus laxity was significantly greater in individuals with OA compared with controls in a majority of studies, while no study found laxity to be significantly greater in controls. Varus-valgus laxity of the knee was reported in persons with OA and varying degrees of frontal plane alignment, disease severity, clinical performance, and self-reported function but no consensus finding could be identified. Females with knee OA appear to have more varus-valgus laxity than males. Meta-analysis was not possible due to the heterogeneity of the subject populations and differences in laxity measurement devices, applied loading, and laxity definitions. Increased varus-valgus laxity is a characteristic of knee joints with OA. Large variances exist in reported varus-valgus laxity and may be due to differences in measurement devices. Prospective studies on joint laxity are needed to identify if increased varus-valgus laxity is a causative factor in OA incidence and progression. PMID:27680888

  6. Hallux valgus (bunions)

    PubMed Central

    2014-01-01

    Introduction Hallux valgus (bunions) are prominent and often inflamed metatarsal heads and overlying bursae. They are associated with valgus deviation of the great toe which moves towards the second toe. Hallux valgus is found in at least 2% of children aged 9 to 10 years, and almost half of adults, with greater prevalence in women. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of conservative treatments for hallux valgus (bunions)? What are the effects of osteotomy for hallux valgus (bunions)? We searched: Medline, Embase, The Cochrane Library, and other important databases up to October 2013 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 15 studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: chevron osteotomy plus adductor tenotomy; distal metatarsal osteotomy; minimally invasive surgery (percutaneous distal metatarsal osteotomy, SERI [Simple, Effective, Rapid, Inexpensive] distal metatarsal osteotomy); phalangeal (Akin) osteotomy plus distal chevron osteotomy; proximal osteotomy; night splints; and orthoses (including antipronatory orthoses in children).

  7. A DYNAMIC VALGUS INDEX THAT COMBINES HIP AND KNEE ANGLES: ASSESSMENT OF UTILITY IN FEMALES WITH PATELLOFEMORAL PAIN.

    PubMed

    Scholtes, Sara A; Salsich, Gretchen B

    2017-06-01

    Two=dimensional motion analysis of lower=extremity movement typically focuses on the knee frontal plane projection angle, which considers the position of the femur and the tibia. A measure that includes the pelvis may provide a more comprehensive and accurate indicator of lower=extremity movement. Hypothesis/Purpose: The purpose of the study was to describe the utility of a two=dimensional dynamic valgus index (DVI) in females with patellofemoral pain. The hypothesis was that the DVI would be more reliable and valid than the knee frontal plane projection angle, be greater in females with patellofemoral pain during a single=limb squat than in females without patellofemoral pain, and decrease in females with patellofemoral pain following instruction. Study Design: Controlled Laboratory Study. Data were captured while participants performed single limb squats under two conditions: usual and corrected. Two=dimensional hip and knee angles and a DVI that combined the hip and knee angles were calculated. Three=dimensional sagittal, frontal, and transverse plane angles of the hip and knee and a DVI combining the frontal and transverse plane angles were calculated. The two=dimensional DVI demonstrated moderate reliability (ICC=0.74). The correlation between the two=dimensional and three=dimensional DVI's was 0.635 (p<0001). Females with patellofemoral pain demonstrated a greater two=dimensional DVI (31.14 °±13.36 °) than females without patellofemoral pain (18.30 °±14.97 °; p=0.010). Females with patellofemoral pain demonstrated a decreased DVI in the corrected (19.04 °±13.70 °) versus usual (31.14 °±13.36 °) condition (p=0.001). The DVI is a reliable and valid measure that may provide a more comprehensive assessment of lower=extremity movement patterns than the knee frontal plane projection angle in individuals with lower=extremity musculoskeletal pain problems. 2b.

  8. Ninety-degree chevron osteotomy for correction of hallux valgus deformity: clinical data and finite element analysis.

    PubMed

    Matzaroglou, Charalambos; Bougas, Panagiotis; Panagiotopoulos, Elias; Saridis, Alkis; Karanikolas, Menelaos; Kouzoudis, Dimitris

    2010-04-22

    Hallux valgus is a very common foot disorder, with its prevalence estimated at 33% in adult shoe-wearing populations. Conservative management is the initial treatment of choice for this condition, but surgery is sometimes needed. The 60(0) angle Chevron osteotomy is an accepted method for correction of mild to moderate hallux valgus in adults less than 60 years old. A modified 90(0) angle Chevron osteotomy has also been described; this modified technique can confer some advantages compared to the 60(0) angle method, and reported results are good. In the current work we present clinical data from a cohort of fifty-one female patients who had surgery for sixty-two hallux valgus deformities. In addition, in order to get a better physical insight and study the mechanical stresses along the two osteotomies, Finite Element Analysis (FEA) was also conducted. FEA indicated enhanced mechanical bonding with the modified 90(0) Chevron osteotomy, because the compressive stresses that keep the two bone parts together are stronger, and the shearing stresses that tend to slide the two bone parts apart are weaker, compared to the typical 60(0) technique. Follow-up data on our patient cohort show good or excellent long-term clinical results with the modified 90(0) angle technique. These results are consistent with the FEA-based hypothesis that a 90(0) Chevron osteotomy confers certain mechanical advantages compared to the typical 60(0) procedure.

  9. Plate fixation for proximal chevron osteotomy has greater risk for hallux valgus recurrence than Kirschner wire fixation.

    PubMed

    Park, Chul-Hyun; Ahn, Ji-Yong; Kim, Yu-Mi; Lee, Woo-Chun

    2013-06-01

    The purpose of this study was to compare the results of hallux valgus surgery between feet fixed with Kirschner wires and those fixed with a plate and screws. Between December 2008 and November 2009, 53 patients (62 feet) were treated with proximal chevron osteotomy and distal soft tissue procedure for symptomatic moderate to severe hallux valgus deformity. Thirty-four patients (41 feet) were stabilised with Kirschner wires (K-wire group) and 19 patients (21 feet) were stabilised with a locking plate (plate group). Clinical results were assessed using American Orthopaedic Foot and Ankle Society (AOFAS) score. Radiographic parameters were compared between these groups. Recurrence rate at the last follow-up was compared between the K-wire and plate groups. Mean AOFAS score was lower in the plate group, however, the difference between the groups was not statistically significant in AOFAS score at the last follow-up. Hallux valgus angle and intermetatarsal angle were significantly larger in the plate group at the last follow-up. Mean 1-2 metatarsal (MT) distance on immediately postoperative radiographs was significant larger in the plate group. Four (9.8 %) of the 41 feet in the K-wire group and 7 (33.3 %) of the 21 feet in the plate group showed hallux valgus recurrence at the last follow-up. The plate group had a significantly higher risk of recurrence than the K-wire group. Fixation of proximal chevron osteotomy using a plate and screws has a greater risk of hallux valgus recurrence than fixation using Kirschner wires.

  10. Proximal Intermetatarsal Divergence in Distal Chevron Osteotomy for Hallux Valgus: An Overlooked Finding.

    PubMed

    Akpinar, Evren; Buyuk, Abdul Fettah; Cetinkaya, Engin; Gursu, Sarper; Ucpunar, Hanifi; Albayrak, Akif

    2016-01-01

    The goal of distal chevron osteotomy for hallux valgus is to restore proper first-toe joint alignment by performing lateral translation of the distal first metatarsal fragment (the metatarsal head). We hypothesized that in some patients this procedure might also result in involuntary medial translation of the proximal first metatarsal fragment, which we called proximal intermetatarsal divergence. The aim of the present study was to compare the pre- and postoperative radiographs of patients with hallux valgus to determine whether we could identify proximal intermetatarsal divergence. We retrospectively compared the pre- and postoperative radiographs of 29 feet in 28 patients treated with distal chevron osteotomy. Two different methods were used to measure the intermetatarsal angles: the anatomic intermetatarsal angle (aIMA) and the mechanical intermetatarsal angle (mIMA). The maximum intermetatarsal distance (MID) was also measured. We defined proximal intermetatarsal divergence as a postoperative increase in the aIMA or MID, coupled with a decrease in the mIMA. For data analysis, we divided the patients into low-angle (mild deformity) and high-angle (severe deformity) groups, according to their preoperative mIMA. The mean ± standard deviation patient age was 41 ± 14 years. In the low-angle group, the mean mIMA decreased (from 10.91° to 7.00°), the mean aIMA increased (from 11.80° to 13.55°), and the mean MID increased (from 17.97 mm to 20.60 mm; p = .001, for all). In the high-angle group, the mean mIMA decreased (from 14.30° to 6.90°; p = .001), the mean aIMA decreased (from 14.77° to 13.54°; p = .06), and the mean MID decreased (from 20.74 mm to 20.37 mm; p = .64). The results of our study suggest that proximal intermetatarsal divergence might occur after distal chevron osteotomy for hallux valgus, primarily in patients with a low preoperative mIMA. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All

  11. Gait analysis in hallux valgus.

    PubMed

    Blomgren, M; Turan, I; Agadir, M

    1991-01-01

    The solar pressure zones were analyzed in the feet of 66 patients suffering from hallux valgus, together with 60 normal subjects. The EMED Gait Analysis System was used. In the hallux valgus group, the maximum pressure was found to be increased significantly in the small toe region and more proximally situated, close to the metatarsophalangeal joint. In the normal subjects, the maximum pressure was increased significantly in the first, second, third, and fourth metatarsal and heel regions. In general, the hallux valgus group had smaller contact areas compared to the control group. The increased pressure in the small toe region, together with the smaller contact areas manifested by the hallux valgus group, were interpreted in this work as being the possible causes of the metatarsalgia seen in patients with the deformity.

  12. Patient's Height and Hip Medial Offset Are the Main Determinants of the Valgus Cut Angle During Total Knee Arthroplasty.

    PubMed

    Drexler, Michael; Abolghasemian, Mansour; Barbuto, Richard; Naini, Mohsen S; Voshmeh, Neda; Rutenberg, Tal F; Schwarzkopf, Ran; Backstein, David J

    2017-05-01

    Valgus cut angle (VCA), defined as the angle between the anatomical and the mechanical axes of femur, is an important parameter upon which a critical step of knee arthroplasty is based. Some variables have been proposed to affect the magnitude of this cut. However, little information is available regarding whether a generic value can be used, or if a patient-specific value from a long leg X-ray, or factors that can be determined preoperatively, is necessary to accurately set the VCA. Standard standing 3-joint views were used to measure a number of anatomical measurements in 358 limbs, 202 patients (116 women, 86 men). Neck-shaft angle, medial offset, femoral length (FL), distal femoral articular angle, and VCA were measured. Demographic data including gender and height were extracted from hospital charts. The correlation of VCA with each of the other factors was evaluated using linear regression and t-test and finally multivariate analysis. The average VCA was 5.76° (range 4-8). Gender and distal femoral articular angle were not related to VCA (P = .343 and .995). FL was found to be a function of height with similar effects on multivariate analysis. Only the height (or FL) and femoral offset were identified as independent factors, with a negative correlation for the former (P < .001) and a positive correlation for the latter (P < .001). Femoral offset and height are the 2 independent factors determining VCA. Other parameters are indirectly related to these 2 factors. Tall patients with a small femoral offset have smaller VCA and short patients with a large offset have larger VCA. The wide variety of VCA values does not support using a generic value for all patients during knee arthroplasty. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Evaluation of Hallux Valgus Correction With Versus Without Akin Proximal Phalanx Osteotomy.

    PubMed

    Shibuya, Naohiro; Thorud, Jakob C; Martin, Lanster R; Plemmons, Britton S; Jupiter, Daniel C

    2016-01-01

    Although the efficacy of Akin proximal phalanx closing wedge osteotomy as a sole procedure for correction of hallux valgus deformity is questionable, when used in combination with other osseous corrective procedures, the procedure has been believed to be efficacious. However, a limited number of comparative studies have confirmed the value of this additional procedure. We identified patients who had undergone osseous hallux valgus correction with first metatarsal osteotomy or first tarsometatarsal joint arthrodesis with (n = 73) and without (n = 81) Akin osteotomy and evaluated their radiographic measurements at 3 points (preoperatively, within 3 months after surgery, and ≥6 months after surgery). We found that those people who had undergone the Akin procedure tended to have a larger hallux abduction angle and a more laterally deviated tibial sesamoid position preoperatively. Although the radiographic correction of the deformity was promising immediately after corrective surgery with the Akin osteotomy, maintenance of the correction was questionable in our cohort. The value of additional Akin osteotomy for correction of hallux valgus deformity is uncertain. Published by Elsevier Inc.

  14. Comparison of outcomes between proximal and distal chevron osteotomy, both with supplementary lateral soft-tissue release, for severe hallux valgus deformity: A prospective randomised controlled trial.

    PubMed

    Park, H-W; Lee, K-B; Chung, J-Y; Kim, M-S

    2013-04-01

    Severe hallux valgus deformity is conventionally treated with proximal metatarsal osteotomy. Distal metatarsal osteotomy with an associated soft-tissue procedure can also be used in moderate to severe deformity. We compared the clinical and radiological outcomes of proximal and distal chevron osteotomy in severe hallux valgus deformity with a soft-tissue release in both. A total of 110 consecutive female patients (110 feet) were included in a prospective randomised controlled study. A total of 56 patients underwent a proximal procedure and 54 a distal operation. The mean follow-up was 39 months (24 to 54) in the proximal group and 38 months (24 to 52) in the distal group. At follow-up the hallux valgus angle, intermetatarsal angle, distal metatarsal articular angle, tibial sesamoid position, American Orthopaedic Foot and Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal score, patient satisfaction level, and complications were similar in each group. Both methods showed significant post-operative improvement and high levels of patient satisfaction. Our results suggest that the distal chevron osteotomy with an associated distal soft-tissue procedure provides a satisfactory method for correcting severe hallux valgus deformity.

  15. Paleopathological study of hallux valgus.

    PubMed

    Mays, S A

    2005-02-01

    Hallux valgus is the abnormal lateral deviation of the great toe. The principal cause is biomechanical, specifically the habitual use of footwear which constricts the toes. In this study, descriptions of the anatomical changes of hallux valgus from published cadaveric and clinical studies were used to generate criteria for identifying the condition in ancient skeletal remains. The value of systematic scoring of hallux valgus in paleopathology is illustrated using two British skeletal series, one dating from the earlier and one from the later Medieval period. It was found that hallux valgus was restricted to later Medieval burials. This appears consistent with archaeological and historical evidence for a rise in popularity, during the late Medieval period (at least among the richer social classes), of narrow, pointed shoes which would have constricted the toes. 2004 Wiley-Liss, Inc.

  16. Modified Chevron osteotomy for hallux valgus deformity in female athletes. A 2-year follow-up study.

    PubMed

    Giotis, Dimitrios; Paschos, Nikolaos K; Zampeli, Franceska; Giannoulis, Dionisios; Gantsos, Apostolos; Mantellos, George

    2016-09-01

    Hallux valgus is an increasingly common deformity in young female athletes that constricts their daily athletic activities and influences foot cosmesis. The aim of this study was to evaluate the outcome of modified Chevron osteotomy for hallux valgus deformity in this specific population. Forty-two cases of modified Chevron osteotomies were carried out in 33 patients with mild to moderate hallux valgus deformity. Each participant was evaluated for AOFAS score, pain, range of motion, cosmetic and radiological outcome. Mean AOFAS score improved to 96.3 (p<0.001) while the mean range of motion of the metatarsophalangeal joint was maintained (p=0.138). The cosmetic result was excellent/good in 40 cases (95%). Mean metatarsophalangeal and intermetatarsal angles were decreased from 29.8° and 14.2° preoperatively to 12.2° and 8.1° postoperatively (p<0.001 and p<0.036), respectively. Modified Chevron osteotomy could offer substantial correction of hallux valgus deformity in young female athletes, with excellent clinical outcome. Copyright © 2015 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  17. Chevron versus Mitchell osteotomy in hallux valgus surgery: a comparative study.

    PubMed

    Lambers Heerspink, F O; Verburg, H; Reininga, I H F; van Raaij, T M

    2015-01-01

    Good clinical results have been reported for chevron and Mitchell osteotomies in mild hallux valgus (HV). The primary aim of the present study was to compare first metatarsal shortening after chevron and Mitchell osteotomies in HV. The secondary outcome measures were the degree of valgus correction, metatarsalgia, and patient satisfaction. A total of 84 patients were included in the present study and were treated from 2005 to 2007; 42 patients were in each group. The outcome measurements-first metatarsal length, HV angle, 1-2 intermetatarsal angle, satisfaction, and metatarsalgia-were taken preoperatively and at follow-up. The Mitchell osteotomy resulted in a significantly larger decrease in the first metatarsal length. No significant difference in transfer metatarsalgia was found. Approximately 30% of patients were mildly or not satisfied after HV surgery. Mitchell osteotomy leads to a larger decrease in the first metatarsal length. Patients with metatarsalgia performed poorly, and no significant differences in metatarsalgia were found. Preventing postoperative metatarsalgia is important for a successful outcome after HV surgery. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Long-term Follow-up of a Randomized Controlled Trial Comparing Scarf to Chevron Osteotomy in Hallux Valgus Correction.

    PubMed

    Jeuken, Ralph M; Schotanus, Martijn G M; Kort, Nanne P; Deenik, Axel; Jong, Bob; Hendrickx, Roel P M

    2016-07-01

    Hallux valgus is one of the most common foot deformities. This long-term follow-up study compared the results of 2 widely used operative treatments for hallux valgus: the scarf and chevron osteotomy. Conventional weight bearing anteroposterior (AP) radiographs of the foot were made for evaluating the intermetatarsal angle and hallux valgus angle. For clinical evaluation, the American Orthopaedic Foot & Ankle Society (AOFAS) rating system for the hallux metatarsophalangeal-interphalangeal scale was used together with physical examination of the foot. These data were compared with the results from the original study. The Short Form 36 questionnaire, the Manchester-Oxford Foot Questionnaire (MOXFQ), and a general questionnaire including a visual analog scale (VAS) pain score were used for subjective evaluation. The primary outcome measures were the radiologic recurrence of hallux valgus and reoperation rate of the same toe. Secondary outcome measures were the results from the radiographs and subjective and clinical evaluation. The response rate was 76% at the follow-up of 14 years; in the chevron group, 37 feet were included compared with 36 feet in the scarf group. Twenty-eight feet in the chevron group and 27 in the scarf group developed recurrence of hallux valgus (P = .483). One patient in the scarf group had a reoperation of the same toe compared with none in the chevron group (P = .314). Current VAS pain scores and results from the SF-36, MOXFQ, and AOFAS did not significantly differ between groups. Both techniques showed similar results after 2 years of follow-up. At 14 years of follow-up, neither technique was superior in preventing recurrence. Level II, randomized controlled trial. © The Author(s) 2016.

  19. Tibial condylar valgus osteotomy (TCVO) for osteoarthritis of the knee: 5-year clinical and radiological results.

    PubMed

    Chiba, Ko; Yonekura, Akihiko; Miyamoto, Takashi; Osaki, Makoto; Chiba, Goji

    2017-03-01

    Tibial condylar valgus osteotomy (TCVO) is a type of opening-wedge high tibial osteotomy for advanced medial knee osteoarthritis (OA) with subluxated lateral joint. We report the concept, the current surgical technique with a locking plate, and the short-term clinical and radiological results of this procedure. 11 knees with medial OA and a widened lateral joint were treated by TCVO (KL stage III: 6, IV: 5). In this procedure, by the L-shaped osteotomy from the medial side of the proximal tibia to the intercondylar eminence and the valgus correction, lateralization of the mechanical axis and reduction of the subluxated lateral joint are obtained with early postoperative weight-bearing. Before, 6 months, 1, and 5 years after the operation, a visual analog scale (VAS), the Western Ontario and McMaster Universities Arthritis Index (WOMAC), alignment of the lower extremity, and congruency and stability of the femorotibial joint were investigated. The VAS improved from an average of 73 mm to 13 mm, and the total WOMAC score from 52 to 14 before to 5 years after the operation, respectively. The mechanical axis changed from 1 to 60%, and the FTA changed from 186° to 171°. The joint line convergence angle (JLCA) changed from 6° to 1°, and the angle difference of JLCA between varus and valgus stress improved from 8° to 4° after the procedure. Improvements in pain and activities of daily living were observed by TCVO along with valgus correction of the lower extremity and stabilization of the femorotibial joint.

  20. Radiographic assessment of knee-ankle alignment after total knee arthroplasty for varus and valgus knee osteoarthritis.

    PubMed

    Gao, Fuqiang; Ma, Jinhui; Sun, Wei; Guo, Wanshou; Li, Zirong; Wang, Weiguo

    2017-01-01

    There are unanswered questions about knee-ankle alignment after total knee arthroplasty (TKA) for varus and valgus osteoarthritis (OA) of the knee. The aim of this retrospective study was to assess knee-ankle alignment after TKA. The study consisted of 149 patients who had undergone TKA due to varus and valgus knee OA. The alignment and angles in the selected knees and ankles were measured on full-length standing anteroposterior radiographs, both pre-operatively and post-operatively. The paired t-test and Pearson's correlation tests were used for statistical analysis. The results showed that ankle alignment correlated with knee alignment both pre-operatively and postoperatively (P<0.05). The pre-operative malalignment of the knee was corrected (P<0.05), and the ankle tilt angle was accordingly improved in the operative side after TKA (P<0.05). In addition, TKA had little effect on knee-ankle alignment on the non-operative side (P>0.05). These findings indicated that routine TKA could correct the varus or valgus deformity of a knee, and improve the tilt of the ankle. Ankle alignment correlated with knee alignment both pre-operatively and postoperatively. Both pre-operative knee and ankle malalignment can be simultaneously corrected following TKA. Level III. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Comparison of the Modified McBride Procedure and the Distal Chevron Osteotomy for Mild to Moderate Hallux Valgus.

    PubMed

    Choi, Gi Won; Kim, Hak Jun; Kim, Taik Seon; Chun, Sung Kwang; Kim, Tae Wan; Lee, Yong In; Kim, Kyoung Ho

    2016-01-01

    Distal metatarsal osteotomy and the modified McBride procedure have each been used for the treatment of mild to moderate hallux valgus. However, few studies have compared the results of these 2 procedures for mild to moderate hallux valgus. The purpose of the present study was to compare the results of distal chevron osteotomy and the modified McBride procedure for treatment of mild to moderate hallux valgus according to the severity of the deformity. We analyzed the data from 45 patients (49.5%; 48 feet [49.0%]), who had undergone an isolated modified McBride procedure (McBride group), and 46 patients (50.5%; 50 feet [51.0%]), who had a distal chevron osteotomy (chevron group). We subdivided each group into those with mild and moderate deformity and compared the clinical and radiologic outcomes between the groups in relation to the severity of the deformity. The improvements in the American Orthopaedic Foot and Ankle Society scale score and the visual analog scale for pain were significantly better for the chevron group for both mild and moderate deformity. The chevron group experienced significantly greater correction in the hallux valgus angle and intermetatarsal angle for both mild and moderate deformity. The chevron group experienced a significantly greater decrease in the grade of sesamoid displacement for patients with moderate deformity. The McBride group had a greater risk of recurrence than did the chevron group for moderate deformity (odds ratio 14.00, 95% confidence interval 3.91 to 50.06, p < .001). The results of the present study have demonstrated the superiority of the distal chevron osteotomy over the modified McBride procedure for mild to moderate deformity. For patients with moderate deformity, the McBride group had a greater risk of hallux valgus recurrence than did the distal chevron group. Therefore, we recommend distal chevron osteotomy rather than a modified McBride procedure for the treatment of mild and moderate hallux valgus. Copyright

  2. Early proximal tibial valgus osteotomy as a very important prognostic factor in Thai children with infantile tibia vara.

    PubMed

    Kaewpornsawan, Kamolporn; Tangsataporn, Suksan; Jatunarapit, Ratiporn

    2005-10-01

    To find the effectiveness of the early surgery (2-3 years of age)as a very important prognostic factor affecting the outcomes in Thai children with infantile tibia vara and all the prognostic factors including the usefulness of arthrographic study in correcting the deformity. From 1994 to 2004, sixteen children aged average 3.61 years old (2.08-7.0) were treated in Siriraj Hospital and diagnosed as infantile tibia vara by Langenskiold radiographic staging were included in the present study and retrospectively reviewed with an average of 6.4 years follow up (range 6 month - 11.1 years). All cases were initially treated by surgery because of low compliance for brace or brace failure. They consisted of 3 boys and 13 girls. There were 24 legs including the bilateral involvement in 8 cases (2 boy and 6 girls). After arihrography, the midshaft fibular osteotomy was performed then the proximal tibial dome-shaped valgus osteotomy was done and fixed with 2 pins. The desired position was 12 degree knee valgus . The patients were divided in two groups, 1)group A,the successful group with the knee becoming normal without any deformity after single osteotomy, 2)group B,the recurrent group with recurrence of the varus deformity required further corrective osteotomies to make normal axis of the knee. All variables were analyzed and compared between group A and group B. The general characteristics and radiographic findings were recorded in 1)age, 2)sex, 3)side, 4)weight in kilogram and in percentage of normal or overweight(obesity) compared with the standard Thai weight chart, 5)tibiofemoral angle (TFA) pre and postoperative treatment, 6) metaphyseal diaphyseal angle (MDA), 7)the medial physeal slope angle (MPS, 8)The preoperative arthrographic articulo-diaphyseal angle (ADA), 9.arthrographic articulo-medial physeal angle (AMPA). There were 14 legs in group A and the remaining 10 legs were in group B (average 2.4 operations). All cases healed in good alignment of the legs without

  3. Treatment of moderate hallux valgus by percutaneous, extra-articular reverse-L Chevron (PERC) osteotomy.

    PubMed

    Lucas y Hernandez, J; Golanó, P; Roshan-Zamir, S; Darcel, V; Chauveaux, D; Laffenêtre, O

    2016-03-01

    The aim of this study was to report a single surgeon series of consecutive patients with moderate hallux valgus managed with a percutaneous extra-articular reverse-L chevron (PERC) osteotomy. A total of 38 patients underwent 45 procedures. There were 35 women and three men. The mean age of the patients was 48 years (17 to 69). An additional percutaneous Akin osteotomy was performed in 37 feet and percutaneous lateral capsular release was performed in 22 feet. Clinical and radiological assessments included the type of forefoot, range of movement, the American Orthopedic Foot and Ankle (AOFAS) score, a subjective rating and radiological parameters. The mean follow-up was 59.1 months (45.9 to 75.2). No patients were lost to follow-up. The mean AOFAS score increased from 62.5 (30 to 80) pre-operatively to 97.1 (75 to 100) post-operatively. A total of 37 patients (97%) were satisfied. At the last follow up there was a statistically significant decrease in the hallux valgus angle, the intermetatarsal angle and the proximal articular set angle. The range of movement of the first metatarsophalangeal joint improved significantly.. There was more improvement in the range of movement in patients who had fixation of the osteotomy of the proximal phalanx. Preliminary results of this percutaneous approach are promising. This technique is reliable and reproducible. Its main asset is that it maintains an excellent range of movement. The PERC osteotomy procedure is an effective approach for surgical management of moderate hallux valgus which combines the benefits of percutaneous surgery with the versatility of the chevron osteotomy whilst maintaining excellent first MTPJ range of motion. ©2016 The British Editorial Society of Bone & Joint Surgery.

  4. The influence of personality traits on the subjective outcome of operative hallux valgus correction.

    PubMed

    Radl, Roman; Leithner, Andreas; Zacherl, Maximilian; Lackner, Ursula; Egger, Josef; Windhager, Reinhard

    2004-10-01

    We studied prospectively the influence of personality traits on the subjective outcome of a chevron osteotomy in 42 patients with hallux valgus. The mean age of patients was 48.3 (20-70) years. Personality traits were evaluated by the means of the Freiburg Personality Inventory (FPI-R). Three months postoperatively 37 patients were satisfied, and five patients not satisfied with the operative procedure. The preoperative AOFAS Score improved from an average of 48.7 (30-65) points to 87.9 (50-100) points. A comparison of satisfied and dissatisfied patients revealed statistically significant differences in the personality traits aggressiveness (p=0.003), extraversion (p=0.001) and health worries (p=0.04). The postoperative hallux valgus angle was 12.2+/-7.8 degrees and 13.4+/-8.3 degrees (p=0.74) among satisfied and not satisfied patients, respectively, and the intermetatarsal angle (I-II) was 7.4+/-2.5 degrees and 7.6+/-4 degrees (p=0.89), respectively. The results suggest that the patient's subjective result after the operative correction may be influenced by some individual, personality profiles.

  5. [Clinical and radiographic evaluation of a new percutaneous technique for moderate to severe hallux valgus deformity].

    PubMed

    Vélez-de Lachica, J C; Valdez-Jiménez, L A; Inzunza-Sánchez, J M

    2017-01-01

    Hallux valgus is considered the most common musculoskeletal deformity, with a prevalence of 88%. There are more than 130 surgical techniques for its treatment; currently, percutaneous ones are popular; however, they do not take into account the metatarsal-phalangeal correction angle. The aim of this study is to propose a modified technique for the correction of the percutaneous metatarsal-phalangeal and inter-metatarsal angles and to evaluate its clinical and radiological results. An experimental, prospective and longitudinal study in 10 patients with moderate to severe hallux valgus according to the classification of Coughlin and Mann were collected; the results were evaluated with the AOFAS scale at 15, 30, 60 and 90 days. The McBride technique and the technique of percutaneous anchor with the proposed amendment were performed. The AOFAS scale was applied as described, finding a progressive increase of the rating; the average correction of the inter-metatarsal angle was 8.8 degrees and of the metatarsal-phalangeal, 9.12. The modified technique of percutaneous anchor showed clear clinical and radiographic improvements in the short term. Our modified technique is proposed for future projects, including a large sample with long-term follow-up.

  6. Distal chevron osteotomy with lateral soft tissue release for moderate to severe hallux valgus decided using intraoperative varus stress radiographs.

    PubMed

    Kim, Hyong-Nyun; Park, Yoo-Jung; Kim, Gab-Lae; Park, Yong-Wook

    2013-01-01

    The purpose of the present study was to investigate the outcomes of distal chevron osteotomy with lateral soft tissue release for moderate to severe hallux valgus. The patients were selected using criteria that included the degree of lateral soft tissue contracture and metatarsocuneiform joint flexibility. The contracture and flexibility were determined from intraoperative varus stress radiographs. From April 2007 to May 2009, 56 feet in 51 consecutive patients with moderate to severe hallux valgus had undergone distal chevron osteotomy with lateral soft tissue release. This was done when the lateral soft tissue contracture was not so severe that passive correction of the hallux valgus deformity was not possible and when the metatarsocuneiform joint was flexible enough to permit additional correction of the first intermetatarsal angle after lateral soft tissue release. The mean patient age was 45.2 (range 23 to 54) years, and the duration of follow-up was 27.5 (range 24 to 46) months. The mean hallux abductus angle decreased from 33.5° ± 3.1° to 11.6° ± 3.3°, and the first intermetatarsal angle decreased from 16.4° ± 2.7° to 9.7° ± 2.1°. The mean American Orthopaedic Foot and Ankle Society hallux-interphalangeal scores increased from 66.6° ± 10.7° to 92.6° ± 9.4° points, and 46 of the 51 patients (90%) were either very satisfied or satisfied with the outcome. No recurrence of deformity or osteonecrosis of the metatarsal head occurred. When lateral soft tissue contracture is not severe and when the metatarsocuneiform joint is flexible enough, distal chevron osteotomy with lateral soft tissue release can be a useful and effective choice for moderate to severe hallux valgus deformity. Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Osteochondral microdamage from valgus bending of the human knee.

    PubMed

    Meyer, Eric G; Villwock, Mark R; Haut, Roger C

    2009-08-01

    Valgus bending of the knee is promoted as an anterior cruciate ligament injury mechanism and is associated with a characteristic "footprint" of bone bruising. The hypothesis of this study was that during ligamentous failure caused by valgus bending of the knee, high tibiofemoral contact pressures induce acute osteochondral microdamage. Four knee pairs were loaded in valgus bending until gross injury with or without a tibiofemoral compression pre-load. The peak valgus moment and resultant motions of the knee joint were recorded. Pressure sensitive film documented the magnitude and location of tibiofemoral contact. Cartilage fissures were documented on the tibial plateau, and microcracks in subchondral bone were documented from micro-computed tomography scans. Injuries were to the anterior cruciate ligament in three knees and the medial collateral ligament in seven knees. The mean (standard deviation) peak bending moment at failure was 107 (64)Nm. Valgus bending produced regions of contact on the lateral tibial plateau with average maximum pressures of approximately 30 (8)MPa. Cartilage fissures and subchondral bone microcracks were observed in these regions of high contact pressure. Combined valgus bending and tibiofemoral compression produce slightly higher contact pressures, but do not alter the gross injury pattern from isolated valgus bending experiments. Athletes who sustain a severe valgus knee bending moment, may be at risk of acute osteochondral damage especially if the loading mechanism occurs with a significant tibiofemoral compression component.

  8. Sharper angle, higher risk? The effect of cutting angle on knee mechanics in invasion sport athletes.

    PubMed

    Schreurs, Mervin J; Benjaminse, Anne; Lemmink, Koen A P M

    2017-10-03

    Cutting is an important skill in team-sports, but unfortunately is also related to non-contact ACL injuries. The purpose was to examine knee kinetics and kinematics at different cutting angles. 13 males and 16 females performed cuts at different angles (45°, 90°, 135° and 180°) at maximum speed. 3D kinematics and kinetics were collected. To determine differences across cutting angles (45°, 90°, 135° and 180°) and sex (female, male), a 4×2 repeated measures ANOVA was conducted followed by post hoc comparisons (Bonferroni) with alpha level set at α≤0.05a priori. At all cutting angles, males showed greater knee flexion angles than females (p<0.01). Also, where males performed all cutting angles with no differences in the amount of knee flexion -42.53°±8.95°, females decreased their knee flexion angle from -40.6°±7.2° when cutting at 45° to -36.81°±9.10° when cutting at 90°, 135° and 180° (p<0.01). Knee flexion moment decreased for both sexes when cutting towards sharper angles (p<0.05). At 90°, 135° and 180°, males showed greater knee valgus moments than females. For both sexes, knee valgus moment increased towards the sharper cutting angles and then stabilized compared to the 45° cutting angle (p<0.01). Both females and males showed smaller vGRF when cutting to sharper angles (p<0.01). It can be concluded that different cutting angles demand different knee kinematics and kinetics. Sharper cutting angles place the knee more at risk. However, females and males handle this differently, which has implications for injury prevention. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. A comparison of proximal and distal chevron osteotomy for the correction of moderate hallux valgus deformity.

    PubMed

    Park, C-H; Jang, J-H; Lee, S-H; Lee, W-C

    2013-05-01

    The purpose of this study was to compare the results of proximal and distal chevron osteotomy in patients with moderate hallux valgus. We retrospectively reviewed 34 proximal chevron osteotomies without lateral release (PCO group) and 33 distal chevron osteotomies (DCO group) performed sequentially by a single surgeon. There were no differences between the groups with regard to age, length of follow-up, demographic or radiological parameters. The clinical results were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) scoring system and the radiological results were compared between the groups. At a mean follow-up of 14.6 months (14 to 32) there were no significant differences in the mean AOFAS scores between the DCO and PCO groups (93.9 (82 to 100) and 91.8 (77 to 100), respectively; p = 0.176). The mean hallux valgus angle, intermetatarsal angle and sesamoid position were the same in both groups. The metatarsal declination angle decreased significantly in the PCO group (p = 0.005) and the mean shortening of the first metatarsal was significantly greater in the DCO group (p < 0.001). We conclude that the clinical and radiological outcome after a DCO is comparable with that after a PCO; longer follow-up would be needed to assess the risk of avascular necrosis.

  10. Parametric study of orthopedic insole of valgus foot on partial foot amputation.

    PubMed

    Guo, Jun-Chao; Wang, Li-Zhen; Chen, Wei; Du, Cheng-Fei; Mo, Zhong-Jun; Fan, Yu-Bo

    2016-01-01

    Orthopedic insole was important for partial foot amputation (PFA) to achieve foot balance and avoid foot deformity. The inapposite insole orthosis was thought to be one of the risk factors of reamputation for foot valgus patient, but biomechanical effects of internal tissues on valgus foot had not been clearly addressed. In this study, plantar pressure on heel and metatarsal regions of PFA was measured using F-Scan. The three-dimensional finite element (FE) model of partial foot evaluated different medial wedge angles (MWAs) (0.0°-10.0°) of orthopedic insole on valgus foot. The effect of orthopedic insole on the internal bone stress, the medial ligament tension of ankle, plantar fascia tension, and plantar pressure was investigated. Plantar pressure on medial heel region was about 2.5 times higher than that of lateral region based on the F-Scan measurements. FE-predicted results showed that the tension of medial ankle ligaments was the lowest, and the plantar pressure was redistributed around the heel, the first metatarsal, and the lateral longitudinal arch regions when MWA of orthopedic insole ranged from 7.5° to 8.0°. The plantar fascias maintained about 3.5% of the total load bearing on foot. However, the internal stresses from foot bones increased. The simulation in this study would provide the suggestion of guiding optimal design of orthopedic insole and therapeutic planning to pedorthist.

  11. Hallux valgus surgery affects kinematic parameters during gait

    PubMed Central

    Klugarova, J.; Janura, M.; Svoboda, Z.; Sos, Z.; Stergiou, N.; Klugar, M.

    2017-01-01

    Background The aim of our study was to compare spatiotemporal parameters and lower limb and pelvis kinematics during the walking in patients with hallux valgus before and after surgery and in relation to a control group. Methods Seventeen females with hallux valgus, who underwent first metatarsal osteotomy, constituted our experimental group. The control group consisted of thirteen females. Kinematic data during walking were obtained using the Vicon MX system. Findings Our results showed that hallux valgus before surgery affects spatiotemporal parameters and lower limb and pelvis kinematics during walking. Hallux valgus surgery further increased the differences that were present before surgery. Specifically after hallux valgus surgery, the walking speed decreased even more (p=0.09, η2= 0.19) while step time increased (p=0.002, η2=0.44) on both legs. The maximum ankle plantar flexion of the operated leg during toe off decreased to a greater extend (p=0.03, η2=0.26). The asymmetry in the hip and the pelvis movements in the frontal plane (present preoperatively) persisted after surgery. Interpretation Hallux valgus is not an isolated problem of the first ray, which could be just surgically addressed by correcting the foot’s alignment. It is a long-term progressive malfunction of the foot affecting the entire kinematic chain of the lower extremity. PMID:27792950

  12. Elbow arthroscopy: valgus extension overload.

    PubMed

    Ahmad, Christopher S; Conway, John E

    2011-01-01

    Valgus torque combined with deceleration produces high compression and shear forces acting on the posteromedial olecranon and the posteromedial trochlea. This valgus extension overload process may cause posteromedial trochlea chondromalacia, chondral flap formation, osteochondrosis, subchondral erosion, a subchondral insufficiency fracture, and marginal exostosis formation. Olecranon pathologies include proximal stress reaction, a posteromedial tip stress fracture, a transverse proximal process stress fracture, exostosis formation, exostosis fragmentation, and intra-articular loose bodies. Symptoms include posteromedial elbow pain during the deceleration phase of the throwing motion. The extension impingement test reproduces posterior or posteromedial pain similar to that experienced while throwing. Special radiographic techniques and CT scans can show loose bodies and osteophyte fragmentation. Surgical treatment is indicated when symptoms persist despite nonsurgical management. Based on clinical and basic science research, all patients with valgus extension overload should be comprehensively evaluated for medial ulnar collateral ligament insufficiency. Surgical treatment is limited to the resection of osteophytes only; normal olecranon should not be resected.

  13. The results of Scarf osteotomy combined with distal soft tissue procedure are mostly satisfactory in surgical management of moderate to severe hallux valgus.

    PubMed

    Şaylı, Uğur; Akman, Budak; Tanrıöver, Altuğ; Kaspar, Çiğdem; Güven, Melih; Özler, Turhan

    2017-05-29

    Intrinsically stable diaphyseal osteotomy gained popularity in recent years for symptomatic hallux valgus deformities. In this study, Scarf osteotomy results, in surgical management of moderate to severe hallux valgus, are presented. Study group consisted of 40 feet of 32 (28 females, four males) patients surgically managed by Scarf osteotomy between September 2009 and 2011, with a mean age of 52,98 (range, 31-75) years at the time of surgery. Patient satisfaction and VAS were used for subjective evaluation while for objective measures AOFAS score, first metatarsophalangeal joint ROM and radiological measurements (intermetatarsal, hallux valgus and distal metatarsal articular angles) were evaluated. Mean follow-up period was 38 (range, 24-60) months. Sixteen feet (40%) were reported as very satisfied, 19 (47,5%) as satisfied and the remaining five (12,5%) as unsatisfied resulting with a total of 35 (87,5%) satisfaction. The mean preoperative VAS and AOFAS forefoot scores improved from 8,13±0,791 to 2,68±1,228 (p=0,0001) and from 58,25±6,15 to 78,25±8,13 (p=0,0001) on the final follow-up, respectively. The postoperative change of first metatarsophalangeal joint ROM was not statistically significant (p=0,281). On the radiological evaluation; intermetatarsal and hallux valgus angles improved from a mean value of 14,77±1,76 to 8,13±1,52° (p=0,0001) and from 35,28±5,86 to 20,10±5,55° (p=0,0001), respectively. Distal metatarsal articular angle did not show any statistically significant change (p=0,195). Scarf osteotomy combined with distal soft tissue procedure is a technically demanding procedure. The osteotomy is intrinsically stable and the correction power is high and the results are mostly satisfactory. Copyright © 2017. Published by Elsevier Ltd.

  14. Venous thrombosis after hallux valgus surgery.

    PubMed

    Radl, Roman; Kastner, Norbert; Aigner, Christian; Portugaller, Horst; Schreyer, Herbert; Windhager, Reinhard

    2003-07-01

    Although surgery for the treatment of hallux valgus is frequently performed, the exact rate of deep vein thrombosis following this procedure is unknown. We performed a single-center, prospective, phlebographically controlled study to quantify the rate of venous thrombosis following operative correction of hallux valgus. Consecutive patients undergoing chevron bunionectomy for correction of hallux valgus deformity were enrolled in the study. Patients with clinical or hematological risk factors for venous thrombosis were excluded. One hundred patients with a mean age of 48.9 years were operated on and did not receive medical prophylaxis against thrombosis. All patients were assessed with phlebography at a mean of twenty-nine days postoperatively. Venous thrombosis was found in four patients (4%). The mean age of these patients (and standard deviation) was 61.7 +/- 6.1 years compared with a mean age of 48.4 +/- 13.9 years for the patients in whom thrombosis did not develop (p = 0.034). Patients are at a low risk for venous thrombosis following surgical treatment of hallux valgus. The need for prophylaxis against thrombosis should be calculated individually for each patient according to his or her known level of risk. Routine medical prophylaxis against thrombosis might be justified for patients over the age of sixty years.

  15. [Clinical effect of total knee arthroplasty on patients with knee osteoarthritis combined with mild to moderate valgus knee deformity].

    PubMed

    Chen, Peng; Zeng, Min; Xie, Jie; Wang, Long; Su, Weiping; Hu, Yihe

    2016-09-28

    To investigate the clinical effect of total knee arthroplasty on patients with knee osteoarthritis combined with mild to moderate valgus knee deformity.
 A total of 15 patients received total knee arthroplasty for correcting mild (10°-15°) to moderate (15°-30°) valgus knee between January 2011 and February 2014 in Xiangya Hospital of Central South University. We adopted a stable prosthesis surgery through patellar medial approach, osteophytes cleaning, conventional osteotomy, a selective soft tissue release and balance technical correcting of knee valgus deformity. Then conventional anticoagulation and symptomatic rehabilitation was utilized. Preoperative and postoperative X-ray was conducted in patients with measuring femor-tibial angle (FTA) and inspecting the prosthesis position. FTA, visual analog scale (VAS) standard, and parallel knee scoring system (KSS) were used to evaluate the clinical effect.
 Fifteen patients were followed up for 14 to 36 (22.40±11.88) months. The hospitalization time was 7-13 (7.73±1.58) d; operative time was 58-110 (81.8±16.85) min, the dominant blood loss was 140-600 (337.30±143.65) mL. Two cases had knee extension hysteresis, and the knee activity recovered after exercise. Leg power lines were normal. Three postoperative cases suffered anterior knee pain. They were subjected to celecoxib analgesic treatment and the pain gradually eased after 3 months. One postoperative case showed incision discharge and swelling, which was healed after change of dressing. During follow-up, review of X-ray film does not show prosthesis loose, subsidence and other complications. The knee valgus angle (8.1±1.8)°, knee motion range (107.33±9.61)°, KSS knee score (74.7±14.5, 75.3±2.7) and pain score (2.5±0.9) were significantly better than the preoperative (P<0.05). The clinical and function KSS scores showed that the improvement rate was 80%. 
 Total knee arthroplasty is an effective way to treat patients with knee osteoarthritis

  16. Angle and Base of Gait Long Leg Axial and Intraoperative Simulated Weightbearing Long Leg Axial Imaging to Capture True Frontal Plane Tibia to Calcaneus Alignment in Valgus and Varus Deformities of the Rearfoot and Ankle.

    PubMed

    Boffeli, Troy J; Waverly, Brett J

    2016-01-01

    The long leg axial view is primarily used to evaluate the frontal plane alignment of the calcaneus in relation to the long axis of the tibia when standing. This view allows both angular measurement and assessment for the apex of varus and valgus deformity of the rearfoot and ankle with clinical utility in the preoperative, intraoperative, and postoperative settings. The frontal plane alignment of the calcaneus to the long axis of the tibia is rarely fixed in the varus or valgus position because of the inherent flexibility of the foot and ankle, which makes patient positioning critical to obtain accurate and reproducible images. Inconsistent patient positioning and imaging techniques are commonly encountered with the long leg axial view for a variety of reasons, including the lack of a standardized or validated protocol. This angle and base of gait imaging protocol involves positioning the patient to align the tibia with the long axis of the foot, which is represented by the second metatarsal. Non-weightbearing long leg axial imaging is commonly performed intraoperatively, which requires a modified patient positioning technique to capture simulated weightbearing long leg axial images. A case series is presented to demonstrate our angle and base of gait long leg axial and intraoperative simulated weightbearing long leg axial imaging protocols that can be applied throughout all phases of patient care for various foot and ankle conditions. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  17. A comparison of proximal and distal Chevron osteotomy, both with lateral soft-tissue release, for moderate to severe hallux valgus in patients undergoing simultaneous bilateral correction: a prospective randomised controlled trial.

    PubMed

    Lee, K B; Cho, N Y; Park, H W; Seon, J K; Lee, S H

    2015-02-01

    Moderate to severe hallux valgus is conventionally treated by proximal metatarsal osteotomy. Several recent studies have shown that the indications for distal metatarsal osteotomy with a distal soft-tissue procedure could be extended to include moderate to severe hallux valgus. The purpose of this prospective randomised controlled trial was to compare the outcome of proximal and distal Chevron osteotomy in patients undergoing simultaneous bilateral correction of moderate to severe hallux valgus. The original study cohort consisted of 50 female patients (100 feet). Of these, four (8 feet) were excluded for lack of adequate follow-up, leaving 46 female patients (92 feet) in the study. The mean age of the patients was 53.8 years (30.1 to 62.1) and the mean duration of follow-up 40.2 months (24.1 to 80.5). After randomisation, patients underwent a proximal Chevron osteotomy on one foot and a distal Chevron osteotomy on the other. At follow-up, the American Orthopedic Foot and Ankle Society (AOFAS) hallux metatarsophalangeal interphalangeal (MTP-IP) score, patient satisfaction, post-operative complications, hallux valgus angle, first-second intermetatarsal angle, and tibial sesamoid position were similar in each group. Both procedures gave similar good clinical and radiological outcomes. This study suggests that distal Chevron osteotomy with a distal soft-tissue procedure is as effective and reliable a means of correcting moderate to severe hallux valgus as proximal Chevron osteotomy with a distal soft-tissue procedure. ©2015 The British Editorial Society of Bone & Joint Surgery.

  18. Conservative management of pes valgus with plantar flexed talus, flexible.

    PubMed

    Bleck, E E; Berzins, U J

    1977-01-01

    The type of flat foot that we have called pes valgus with plantar flexed talus, flexible, was treated in children with the Helfet heel seat or the UCBL shoe insert. In follow-up examination of 71 cases for periods longer than one year, 79 per cent of the patients showed that the UCBL shoe insert and the Helfet heel seat improved the clinical and roentgenographic appearance of the foot. The Helfet heel seat is recommended in cases where the plantar flexion angle of the talus is 35 to 45 degrees and the UCBL shoe insert in those cases of plantar flexion of the talus greater than 45 degrees.

  19. Factors Associated With Early Loss of Hallux Valgus Correction.

    PubMed

    Shibuya, Naohiro; Kyprios, Evangelos M; Panchani, Prakash N; Martin, Lanster R; Thorud, Jakob C; Jupiter, Daniel C

    Recurrence is common after hallux valgus corrective surgery. Although many investigators have studied the risk factors associated with a suboptimal hallux position at the end of long-term follow-up, few have evaluated the factors associated with actual early loss of correction. We conducted a retrospective cohort study to identify the predictors of lateral deviation of the hallux during the postoperative period. We evaluated the demographic data, preoperative severity of the hallux valgus, other angular measurements characterizing underlying deformities, amount of hallux valgus correction, and postoperative alignment of the corrected hallux valgus for associations with recurrence. After adjusting for the covariates, the only factor associated with recurrence was the postoperative tibial sesamoid position. The recurrence rate was ~50% and ~60% when the postoperative tibial sesamoid position was >4 and >5 on the 7-point scale, respectively. Published by Elsevier Inc.

  20. Effects of foot rotation positions on knee valgus during single-leg drop landing: Implications for ACL injury risk reduction.

    PubMed

    Teng, P S P; Kong, P W; Leong, K F

    2017-06-01

    Non-contact anterior cruciate ligament (ACL) injuries commonly occur when athletes land in high risk positions such as knee valgus. The position of the foot at landing may influence the transmission of forces from the ankle to the knee. Using an experimental approach to manipulate foot rotation positions, this study aimed to provide new insights on how knee valgus during single-leg landing may be influenced by foot positions. Eleven male recreational basketball players performed single-leg drop landings from a 30-cm high platform in three foot rotation positions (toe-in, toe-forward and toe-out) at initial contact. A motion capture system and a force plate were used to measure lower extremity kinematics and kinetics. Knee valgus angles at initial contact (KVA) and maximum knee valgus moments (KVM), which were known risk factors associated with ACL injury, were measured. A one-way repeated measures Analysis of Variance was conducted (α=0.05) to compare among the three foot positions. Foot rotation positions were found to have a significant effect on KVA (p<0.001, η 2 =0.66) but the difference between conditions (about 1°) was small and not clinically meaningful. There was a significant effect of foot position on KVM (p<0.001, η 2 =0.55), with increased moment observed in the toe-out position as compared to toe-forward (p=0.012) or toe-in positions (p=0.002). When landing with one leg, athletes should avoid extreme toe-out foot rotation positions to minimise undesirable knee valgus loading associated with non-contact ACL injury risks. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Interventions for treating hallux valgus (abductovalgus) and bunions.

    PubMed

    Ferrari, J; Higgins, J P T; Prior, T D

    2004-01-01

    general, there was no advantage or disadvantage using Keller's over the other techniques. When the distal osteotomy was compared to Keller's arthroplasty, the osteotomy showed evidence of improving the intermetatarsal angle and preserving joint range of motion. The arthroplasty was found to have less of an impact on walking ability compared to the arthrodesis. Six trials involving 309 participants compared chevron (and chevron-type) osteotomy with other techniques. The chevron osteotomy offered no advantages in these trials. For some outcomes, other techniques gave better results. Two of these trials (94 participants) compared a type of proximal osteotomy to a proximal chevron osteotomy and found no evidence of a difference in outcomes between techniques. Three trials involving 157 participants compared outcomes between original operations and surgeon's adaptations. There was no advantage found for any of the adaptations. Three trials involving 71 people with hallux valgus compared new methods of fixation to traditional methods. There was no evidence that the new methods of fixation were detrimental to the outcome of the patients. Four trials involving 162 participants evaluated methods of post-operative rehabilitation. The use of continuous passive motion appeared to give an improved range of motion and earlier recovery following surgery. Early weightbearing or the use of a crepe bandage were not found to be detrimental to final outcome. Only a few studies had considered conservative treatments. The evidence from these suggested that orthoses and night splints did not appear to be any more beneficial in improving outcomes than no treatment. Surgery (chevron osteotomy) was shown to be beneficial compared to orthoses or no treatment, but when compared to other osteotomies, no technique was shown to be superior to any other. Only one trial had compared an osteotomy to an arthroplasty. There was limited evidence to suggest that the osteotomy gat the osteotomy gave the better

  2. Current surgical strategies for total arthroplasty in valgus knee

    PubMed Central

    Nikolopoulos, Dimitrios; Michos, Ioannis; Safos, George; Safos, Petros

    2015-01-01

    The majority of orthopaedic surgeons even currently agree that primary total arthroplasty in valgus knees with a deformity of more than ten degrees may prove challenging. The unique sets of bone and soft tissue abnormalities that must be addressed at the time of the operation make accurate axis restoration, component orientation and joint stability attainment a difficult task. Understanding the specific pathologic anatomic changes associated with the valgus knee is a prerequisite so as to select the proper surgical method, to optimize component position and restore soft-tissue balance. The purpose of this article is to review the valgus knee anatomical variations, to assess the best pre-operative planning and to evaluate how to choose the grade of constraint of the implant. It will also be underlying the up-to-date main approaches and surgical techniques be proposed in the English literature both for bone cuts and soft tissue management of valgus knees. PMID:26191494

  3. Weightbearing CT in normal hindfoot alignment - Presence of a constitutional valgus?

    PubMed

    Burssens, A; Van Herzele, E; Leenders, T; Clockaerts, S; Buedts, K; Vandeputte, G; Victor, J

    2017-02-16

    The normal hindfoot angle is estimated between 2° and 6° of valgus in the general population. These results are solely based on clinical findings and plain radiographs. The purpose of this study is to assess the hindfoot alignment using weightbear CT. Forty-eight patients, mean age of 39.6±13.2 years, with clinical and radiological absence of hindfoot pathology were included. A weightbear CT was obtained and allowed to measure the anatomical tibia axis (TAx) and the hindfoot alignment (HA). The HA was firstly determined using the inferior point of the calcaneus (HA IC ). A density measurement of this area was subsequently performed to analyze if this point concurred with an increased ossification, indicating a higher load exposure. Secondly the HA was determined by dividing the calcaneus in the long axial view (HALA) and compared to the (HA IC ) to point out any possible differences attributed to the measurement method. Reliability was assessed using an intra class correlation coefficient (ICC). The mean HA IC equaled 0.79° of valgus±3.2 (ICC HA IC =0.73) with a mean TAx of 2.7° varus±2.1 (ICCTA=0.76). The HALA equaled 9.1° of valgus±4.8 (ICCHA LA=0.71) and differed significantly by a P<0.001 from the HA IC , which showed a more neutral alignment. Correlation between both was shown to be good by a Spearman's correlation coefficient of 0.74. The mean density of the inferior calcaneal area equaled 271.3±84.1 and was significantly higher than the regional calcaneal area (P<0.001). These results show a more neutral alignment of the hindfoot in this group of non-symptomatic feet as opposed to the generally accepted constitutional valgus. This could have repercussion on hindfoot position during fusion or in quantifying the correction of a malalignment. The inferior calcaneus point in this can be used during pre-operative planning of a hindfoot correction as an anatomical landmark due to its shown influence on load transfer. Copyright © 2017 European Foot and

  4. Clinical relevance of valgus deformity of proximal femur in cerebral palsy.

    PubMed

    Lee, Kyoung Min; Kang, Jong Yeol; Chung, Chin Youb; Kwon, Dae Gyu; Lee, Sang Hyeong; Choi, In Ho; Cho, Tae-Joon; Yoo, Won Joon; Park, Moon Seok

    2010-01-01

    Proximal femoral deformity related to physis has not been studied in patients with cerebral palsy (CP). This study was performed to investigate the clinical relevance of neck shaft angle (NSA), head shaft angle (HSA), and proximal femoral epiphyseal shape in patients with CP, which represent the deformities of metaphysis, physis, and epiphysis, respectively. Three hundred eighty-four patients with CP (mean age 9.1 y, 249 males and 135 females) were included. Extent of involvement and functional states [Gross Motor Function Classification System (GMFCS) level] were obtained. Radiographic measurements including NSA, HSA, and qualitative shape of the proximal femoral epiphysis were evaluated and analyzed according to extent of involvement and GMFCS level. Reliability and correlation with each measurement were assessed. Multiple regression test was performed to examine the significant contributing factors to migration percentage (MP) that represents hip instability. NSA showed excellent interobserver reliability with intraclass correlation coefficients of 0.976. Correlation with the MP was higher in the NSA (r=0.419, P<0.001) than in the HSA (r=0.256, P<0.001). NSA, HSA, and MP tended to increase with increasing GMFCS level, and proportion of valgus deformed proximal femoral epiphysis also increased with increasing GMFCS level, which means valgus deformity and unstable hips in the less favorable functional states. Multiple regression analysis revealed NSA, GMFCS level, and shape of the proximal femoral epiphysis to be significant factors affecting MP. NSA appeared to be more clinically relevant than HSA in evaluating proximal femoral deformity in patients with CP. Shape of proximal femoral epiphysis is believed to have clinical implications in terms of hip instability. Diagnostic level II.

  5. The relationship of abnormal foot pronation to hallux abducto valgus--a pilot study.

    PubMed

    Ross, F D

    1986-08-01

    Abnormal foot mechanics is the most common cause of hallux abducto valgus. To date no quantitative data regarding the relationship between abnormal foot mechanics and the degree of hallux abducto valgus has been presented. An outline of the abnormal foot mechanics responsible for hallux abducto valgus is described along with a technique for measuring the extent of abnormal function. A common intrinsic abnormality responsible for hallux abducto valgus is described along with its diagnosis and orthotic treatment.

  6. Correlation between static radiographic measurements and intersegmental angular measurements during gait using a multisegment foot model.

    PubMed

    Lee, Dong Yeon; Seo, Sang Gyo; Kim, Eo Jin; Kim, Sung Ju; Lee, Kyoung Min; Farber, Daniel C; Chung, Chin Youb; Choi, In Ho

    2015-01-01

    Radiographic examination is a widely used evaluation method in the orthopedic clinic. However, conventional radiography alone does not reflect the dynamic changes between foot and ankle segments during gait. Multiple 3-dimensional multisegment foot models (3D MFMs) have been introduced to evaluate intersegmental motion of the foot. In this study, we evaluated the correlation between static radiographic indices and intersegmental foot motion indices. One hundred twenty-five females were tested. Static radiographs of full-leg and anteroposterior (AP) and lateral foot views were performed. For hindfoot evaluation, we measured the AP tibiotalar angle (TiTA), talar tilt (TT), calcaneal pitch, lateral tibiocalcaneal angle, and lateral talcocalcaneal angle. For the midfoot segment, naviculocuboid overlap and talonavicular coverage angle were calculated. AP and lateral talo-first metatarsal angles and metatarsal stacking angle (MSA) were measured to assess the forefoot. Hallux valgus angle (HVA) and hallux interphalangeal angle were measured. In gait analysis by 3D MFM, intersegmental angle (ISA) measurements of each segment (hallux, forefoot, hindfoot, arch) were recorded. ISAs at midstance phase were most highly correlated with radiography. Significant correlations were observed between ISA measurements using MFM and static radiographic measurements in the same segment. In the hindfoot, coronal plane ISA was correlated with AP TiTA (P < .001) and TT (P = .018). In the hallux, HVA was strongly correlated with transverse ISA of the hallux (P < .001). The segmental foot motion indices at midstance phase during gait measured by 3D MFM gait analysis were correlated with the conventional radiographic indices. The observed correlation between MFM measurements at midstance phase during gait and static radiographic measurements supports the fundamental basis for the use of MFM in analysis of dynamic motion of foot segment during gait. © The Author(s) 2014.

  7. Correction of moderate to severe hallux valgus with combined proximal opening wedge and distal chevron osteotomies: a reliable technique.

    PubMed

    Jeyaseelan, L; Chandrashekar, S; Mulligan, A; Bosman, H A; Watson, A J S

    2016-09-01

    The mainstay of surgical correction of hallux valgus is first metatarsal osteotomy, either proximally or distally. We present a technique of combining a distal chevron osteotomy with a proximal opening wedge osteotomy, for the correction of moderate to severe hallux valgus. We reviewed 45 patients (49 feet) who had undergone double osteotomy. Outcome was assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) and the Short Form (SF) -36 Health Survey scores. Radiological measurements were undertaken to assess the correction. The mean age of the patients was 60.8 years (44.2 to 75.3). The mean follow-up was 35.4 months (24 to 51). The mean AOFAS score improved from 54.7 to 92.3 (p < 0.001) and the mean SF-36 score from 59 to 86 (p < 0.001). The mean hallux valgus and intermetatarsal angles were improved from 41.6(o) to 12.8(o) (p < 0.001) and from 22.1(o) to 7.1(o), respectively (p < 0.001). The mean distal metatarsal articular angle improved from 23(o) to 9.7(o). The mean sesamoid position, as described by Hardy and Clapham, improved from 6.8 to 3.5. The mean length of the first metatarsal was unchanged. The overall rate of complications was 4.1% (two patients). These results suggest that a double osteotomy of the first metatarsal is a reliable, safe technique which, when compared with other metatarsal osteotomies, provides strong angular correction and excellent outcomes with a low rate of complications. Cite this article: Bone Joint J 2016;98-B:1202-7. ©2016 The British Editorial Society of Bone & Joint Surgery.

  8. WITHDRAWN: Interventions for treating hallux valgus (abductovalgus) and bunions.

    PubMed

    Ferrari, Jill; Higgins, Julian Pt; Prior, Trevor D

    2009-04-15

    . In general, there was no advantage or disadvantage using Keller's over the other techniques. When the distal osteotomy was compared to Keller's arthroplasty, the osteotomy showed evidence of improving the intermetatarsal angle and preserving joint range of motion. The arthroplasty was found to have less of an impact on walking ability compared to the arthrodesis.Six trials involving 309 participants compared chevron (and chevron-type) osteotomy with other techniques. The chevron osteotomy offered no advantages in these trials. For some outcomes, other techniques gave better results. Two of these trials (94 participants) compared a type of proximal osteotomy to a proximal chevron osteotomy and found no evidence of a difference in outcomes between techniques.Three trials involving 157 participants compared outcomes between original operations and surgeon's adaptations. There was no advantage found for any of the adaptations.Three trials involving 71 people with hallux valgus compared new methods of fixation to traditional methods. There was no evidence that the new methods of fixation were detrimental to the outcome of the patients.Four trials involving 162 participants evaluated methods of post-operative rehabilitation. The use of continuous passive motion appeared to give an improved range of motion and earlier recovery following surgery. Early weightbearing or the use of a crepe bandage were not found to be detrimental to final outcome. Only a few studies had considered conservative treatments. The evidence from these suggested that orthoses and night splints did not appear to be any more beneficial in improving outcomes than no treatment. Surgery (chevron osteotomy) was shown to be beneficial compared to orthoses or no treatment, but when compared to other osteotomies, no technique was shown to be superior to any other. Only one trial had compared an osteotomy to an arthroplasty. There was limited evidence to suggest that the osteotomy gave the better outcomes. It

  9. Computational prediction and experimental verification of HVA1-like abscisic acid responsive promoters in rice (Oryza sativa).

    PubMed

    Ross, Christian; Shen, Qingxi J

    2006-09-01

    Abscisic acid (ABA) is one of the central plant hormones, responsible for controlling both maturation and germination in seeds, as well as mediating adaptive responses to desiccation, injury, and pathogen infection in vegetative tissues. Thorough analyses of two barley genes, HVA1 and HVA22, indicate that their response to ABA relies on the interaction of two cis-acting elements in their promoters, an ABA response element (ABRE) and a coupling element (CE). Together, they form an ABA response promoter complex (ABRC). Comparison of promoters of barley HVA1 and it rice orthologue indicates that the structures and sequences of their ABRCs are highly similar. Prediction of ABA responsive genes in the rice genome is then tractable to a bioinformatics approach based on the structures of the well-defined barley ABRCs. Here we describe a model developed based on the consensus, inter-element spacing and orientations of experimentally determined ABREs and CEs. Our search of the rice promoter database for promoters that fit the model has generated a partial list of genes in rice that have a high likelihood of being involved in the ABA signaling network. The ABA inducibility of some of the rice genes identified was validated with quantitative reverse transcription PCR (QPCR). By limiting our input data to known enhancer modules and experimentally derived rules, we have generated a high confidence subset of ABA-regulated genes. The results suggest that the pathways by which cereals respond to biotic and abiotic stresses overlap significantly, and that regulation is not confined to the level transcription. The large fraction of putative regulatory genes carrying HVA1-like enhancer modules in their promoters suggests the ABA signal enters at multiple points into a complex regulatory network that remains largely unmapped.

  10. Valgus extension overload syndrome and stress injury of the olecranon.

    PubMed

    Ahmad, Christopher S; ElAttrache, Neal S

    2004-10-01

    Basic science studies have improved our understanding of the pathomechanics for valgus extension overload and olecranon stress fractures. These disorders result from repetitive abutment of the olecranon into the olecranon fossa combined with valgus torques, resulting in impaction and shear along the posteromedial olecranon. The patient history and physical examination are similar for each disorder. Imaging studies including plain radiographs, computed tomography, MRI or bone scan may be necessary for accurate diagnosis. Clinical and basic science support mandatory and careful assessment of the medial collateral ligament when valgus extension overload is identified and limited debridement of the olecranon when surgery is indicated. For stress fractures that fail nonoperative management, treatment with internal fixation provides good results.

  11. Finite element analysis of the valgus knee joint of an obese child.

    PubMed

    Sun, Jun; Yan, Songhua; Jiang, Yan; Wong, Duo Wai-Chi; Zhang, Ming; Zeng, Jizhou; Zhang, Kuan

    2016-12-28

    Knee valgus and varus morbidity is at the second top place in children lower limb deformity diseases. It may cause abnormal stress distribution. The magnitude and location of contact forces on tibia plateau during gait cycle have been indicated as markers for risk of osteoarthritis. So far, few studies reported the contact stress and force distribution on tibial plateau of valgus knee of children. To estimate the contact stresses and forces on tibial plateau of an 8-year old obese boy with valgus knee and a 7-year old healthy boy, three-dimensional (3D) finite element (FE) models of their left knee joints were developed. The valgus knee model has 36,897 nodes and 1,65,106 elements, and the normal knee model has 78,278 nodes and 1,18,756 elements. Paired t test was used for the comparison between the results from the 3D FE analysis method and the results from traditional kinematic measurement methods. The p value of paired t test is 0.12. Maximum stresses shifted to lateral plateau in knee valgus children while maximum stresses were on medial plateau in normal knee child at the first peak of vertical GRF of stance phase. The locations of contact centers on medial plateau changed 3.38 mm more than that on lateral plateau, while the locations of contact centers on medial plateau changed 1.22 mm less than that on lateral plateau for healthy child from the first peak to second peak of vertical GRF of stance phase. The paired t test result shows that there is no significant difference between the two methods. The results of FE analysis method suggest that knee valgus malalignment could be the reason for abnormal knee load that may cause knee problems in obese children with valgus knee in the long-term. This study may help to understand biomechanical mechanism of valgus knees of obese children.

  12. Developmental pattern of tibiofemoral angle in healthy north-east Indian children.

    PubMed

    Baruah, R K; Kumar, S; Harikrishnan, S V

    2017-10-01

    Physiological range of tibiofemoral angle (TFA) is poorly defined and may lead to unnecessary therapeutic interventions. Studies on TFA developmental pattern suggest that racial and ethnic differences are present; children in north-east India who have not yet been studied need to be evaluated. Cross-sectional study of clinical TFA, intermalleolar distance and intercondylar distance in 1020 healthy north-east Indian children aged from 2 to 18 years was done. Height, weight and body mass index were also recorded. At two years of age the mean TFA was valgus. The values reached a peak of 8.55° (standard deviation (SD) 1.01) valgus at seven years of age. The TFA then gradually stabilised to 3.18° (SD 1.18) valgus by 18 years of age. There was no significant difference in TFA between male and female patients. The present study is the largest and only the third such study on Indian children and the first on healthy northeast Indian children. By the end of two years most children had valgus angulation. This, along with the peak angulation observed, was similar to most of the other studies. The age at peak angulation and subsequent stabilisation of valgus angulation varied greatly among children of different origins, especially non-Indian children. Data can be used to identify children who require further follow-up/evaluation and can serve as guidelines during deformity correction and future studies. The development of TFA in this cohort is not different from other children of India but differs from children of other ethnic origins.

  13. Total knee arthroplasty for severe valgus knee deformity.

    PubMed

    Zhou, Xinhua; Wang, Min; Liu, Chao; Zhang, Liang; Zhou, Yixin

    2014-01-01

    Primary total knee arthroplasty (TKA) in severe valgus knees may prove challenging, and choice of implant depends on the severity of the valgus deformity and the extent of soft-tissue release. The purpose of this study was to review 8 to 11 years (mean, 10 years) follow-up results of primary TKA for varient-III valgus knee deformity with use of different type implants. Between January 2002 and January 2005, 20 women and 12 men, aged 47 to 63 (mean, 57.19 ± 6.08) years old, with varient-III valgus knees underwent primary TKA. Of the 32 patients, 37 knees had varient-III deformities. Pie crusting was carefully performed with small, multiple inside-out incisions, bone resection balanced the knee in lieu of soft tissue releases that were not used in the series. Cruciate-retaining knees (Gemini MKII, Link Company, Germany) were used in 13 knees, Genesis II (Simth & Nephew Company, USA) in 14 knees, and hinged knee (Endo-Model Company, Germany) in 10 knees. In five patients with bilateral variant-III TKAs, three patients underwent 1-stage bilateral procedures, and two underwent 2-stage procedures. All implants were cemented and the patella was not resurfaced. The Hospital for Special Surgery (HSS) knee score was assessed. Patients were followed up from 8 to 11 years. The mean HSS knee score were improved from 50.33 ± 11.60 to 90.06 ± 3.07 (P < 0.001). The mean tibiofemoral alignment were improved from valgus 32.72° ± 9.68° pre-operation to 4.89° ± 0.90° post-operation (P < 0.001). The mean range of motion were improved from 93.72° ± 23.69° pre-operation to 116.61 ± 16.29° post-operation (P < 0.001). No patients underwent revision. One patient underwent open reduction and internal fixation using femoral condylar plates for supracondylar femoral fractures secondary to a fall at three years. Three patients developed transient peroneal nerve palsies, which resolved within nine months. Two patients developed symptomatic deep vein thrombosis that was managed with

  14. Inter and intra-observer reliability in assessment of the position of the lateral sesamoid in determining the severity of hallux valgus.

    PubMed

    Panchani, Sunil; Reading, Jonathan; Mehta, Jaysheel

    2016-06-01

    The position of the lateral sesamoid on standard dorso-plantar weight bearing radiographs, with respect to the lateral cortex of the first metatarsal, has been shown to correlate well with the degree of the hallux valgus angle. This study aimed to assess the inter- and intra-observer error of this new classification system. Five orthopaedic consultants and five trainee orthopaedic surgeons were recruited to assess and document the degree of displacement of the lateral sesamoid on 144 weight-bearing dorso-plantar radiographs on two separate occasions. The severity of hallux valgus was defined as normal (0%), mild (≤50%), moderate (51-≤99%) or severe (≥100%) depending on the percentage displacement of the lateral sesamoid body from the lateral cortical border of the first metatarsal. Consultant intra-observer variability showed good agreement between repeated assessment of the radiographs (mean Kappa=0.75). Intra-observer variability for trainee orthopaedic surgeons also showed good agreement with a mean Kappa=0.73. Intraclass correlations for consultants and trainee surgeons was also high. The new classification system of assessing the severity of hallux valgus shows high inter- and intra-observer variability with good agreement and reproducibility between surgeons of consultant and trainee grades. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. The Gibson and Piggott osteotomy for adult hallux valgus.

    PubMed

    Rangrez, Arshad Bashir; Dar, Tahir Ahmed; Badoo, Abdul Rashid; Wani, Sharief Ahmed; Dhar, Shabir Ahmed; Mumtaz, Imran; Ahmed, Muzzaffar

    2012-01-01

    The Gibson and Piggott procedure for hallux valgus is based on sound surgical principles addressing the basic pathologies of this disorder. However, this procedure has not been studied extensively in the literature in comparison to the Mitchell and Chevron osteotomies. We report a prospective study conducted on 50 adult feet with hallux valgus. The Gibson and Piggot osteotomy was done on all the feet. We obtained 76% excellent and 18% good results with this procedure. The results bear out the fact that this procedure is a useful procedure for the management of this disorder.

  16. Impact of Soft Tissue Imbalance on Knee Flexion Angle After Posterior Stabilized Total Knee Arthroplasty.

    PubMed

    Tsukada, Sachiyuki; Fujii, Tomoko; Wakui, Motohiro

    2017-08-01

    This study was performed to assess the impact of soft tissue imbalance on the knee flexion angle 2 years after posterior stabilized total knee arthroplasty (TKA). A total of 329 consecutive varus knees were included to assess the association of knee flexion angle 2 years after TKA with preoperative, intraoperative, and postoperative variables. All intraoperative soft tissue measurements were performed by a single surgeon under spinal anesthesia in a standardized manner including the subvastus approach, reduced patella, and without use of a pneumonic tourniquet. Multiple linear regression analysis showed no significant correlations in terms of intraoperative valgus imbalance at 90-degree flexion or the difference in soft tissue tension between 90-degree flexion and 0-degree extension (β = -0.039; 95% confidence interval [CI], -0.88 to 0.80; P = .93 and β = 0.015; 95% CI, -0.29 to 0.32; P = .92, respectively). Preoperative flexion angle was significantly correlated with knee flexion angle 2 years after TKA (β = 0.42; 95% CI, 0.33 to 0.51; P < .0001). Avoiding valgus imbalance at 90-degree flexion and aiming for strictly equal soft tissue tension between 90-degree flexion and 0-degree extension had little practical value with regard to knee flexion angle 2 years after posterior stabilized TKA. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  17. Plantar pressures determinants in mild Hallux Valgus.

    PubMed

    Martínez-Nova, Alfonso; Sánchez-Rodríguez, Raquel; Pérez-Soriano, Pedro; Llana-Belloch, Salvador; Leal-Muro, Alejo; Pedrera-Zamorano, Juan Diego

    2010-07-01

    While podobarometric techniques have been applied to the study of pressures in Hallux Valgus (HV), little is known about its clinical and radiological determinants. So, the aim of the present study was to determine the plantar pressure pattern in participants with mild HV, comparing to a control group, and their clinical and anthropometric determinants. Biofoot/IBV(®) in-shoe system was used to evaluate 79 participants with mild HV. Computerized measurements of the 1st intermetatarsal angle (IMA) and the hallux abductus angle (HAA) were made on antero-posterior radiographs. The clinical outcome was assessed using the AOFAS score. The dependent baropodometric variables and the independent clinical and anthropometric variables were subjected to a multiple regression analysis. In both groups, the highest average pressure was in the 2nd metatarsal head (MTH). The mean pressure under the Hallux was significantly higher in HV group (controls, 146.5±92.5kPa; HV, 328.5±113.2kPa; p<0.001). An 18.6% of average pressure under the 1st MTH was accounted for pain, first ray alignment and total AOFAS score. Variations of the HAA explained 26.8% of the mean Hallux pressure. Women with mild HV present with pathologically increased pressure under the Hallux, which is caused by the altered alignment of the first ray. Pain and clinical result were associated with the pressure under the 1st MTH and the remaining variables were only moderate predictors of dynamic plantar pressures. Copyright © 2010 Elsevier B.V. All rights reserved.

  18. Associations of beta-endorphin with HVA and MHPG in the plasma of prepubertal boys: effects of familial drug abuse and antisocial personality disorder liability.

    PubMed

    Moss, H B; Yao, J K

    1996-06-01

    It is well-established that the secretion of the opioid neuropeptide beta-endorphin is perturbed by the administration of various drugs of abuse. Several investigators have speculated that variations in beta-endorphin secretory regulation may precede the development of a substance use disorder, and thus be a component of the liability for substance abuse. In order to test this hypothesis, we examined fasting, morning plasma concentrations of beta-endorphin and two catecholamine metabolites in prepubertal boys naive to drugs of abuse and at elevated familial risk for a substance use disorder (SA+), and in controls (SA-). Specifically, the dopaminergic metabolite homovanillic acid (pHVA), and the noradrenergic metabolite, 3-methoxy-4-hydroxy-phenylglycol (pMHPG) were measured. Between-group differences were not found for beta-endorphin, pHVA, or pMHPG. Similarly, such differences did not differentiate sons of fathers with Antisocial Personality Disorder and controls. However, regression analysis revealed that although both pHVA and pMHPG predicted beta-endorphin concentrations to similar degrees, the directions of influence were the opposite. pHVA was found to be positively associated with beta-endorphin while pMHPG was found to be negatively associated with beta-endorphin. No between-group differences in these relationships were found. The results suggest an opponent process in catecholaminergic regulation of beta-endorphin in humans, and are consistent with observations in the central nervous system of animal models.

  19. [Dynamic plantar pressure distribution after percutaneous hallux valgus correction using the Reverdin-Isham osteotomy].

    PubMed

    Rodríguez-Reyes, Gerardo; López-Gavito, Eduardo; Pérez-Sanpablo, Alberto Isaac; Galván Duque-Gastélum, Carlos; Alvarez-Camacho, Michelín; Mendoza-Cruz, Felipe; Parra-Téllez, Patricia; Vázquez-Escamilla, Jesús; Quiñones-Urióstegui, Ivett

    2014-07-01

    Percutaneous surgical techniques are suitable for the correction of the hallux valgus deformity. Satisfactory aesthetic and functional results obtained with the Reverdin- Isham osteotomy have been reported. The aim of this study was to describe dynamic plantar pressure redistribution after the correction of the deformity using this technique. A sample of 20 feet with mild or moderate hallux valgus was conformed and surgically treated using the Reverdin-Isham osteotomy. Clinical, radiological, surface and pressure assessments were performed pre and postoperatively. Postoperative mean (± SD) values of the American Orthopaedic Foot and Ankle Society (AOFAS) score, metatarsophalangeal, first intermetatarsal and proximal articular sect angles were 95.7 (3.3), 15.5° (5.4), 9.5° (1.5) y 5.3° (3.0), respectively. A significant decrease was observed in surface values of both lateral (P = 0.003) and medial (P = 0.001) masks of the forefoot. Mean pressure values of the lateral forefoot region denoted a significant increase (P < 0.001) while the medial forefoot region showed no change (P = 0.137). There is evidence that this particular surgical technique promotes a new plantar pressure pattern in the foot that might significantly favour the increase of the pressure observed under the lesser metatarsal heads and might not induce meaningful changes in the mean pressure registered under the first metatarsal head and hallux.

  20. A numerical simulation approach to studying anterior cruciate ligament strains and internal forces among young recreational women performing valgus inducing stop-jump activities.

    PubMed

    Kar, Julia; Quesada, Peter M

    2012-08-01

    Anterior cruciate ligament (ACL) injuries are commonly incurred by recreational and professional women athletes during non-contact jumping maneuvers in sports like basketball and volleyball, where incidences of ACL injury is more frequent to females compared to males. What remains a numerical challenge is in vivo calculation of ACL strain and internal force. This study investigated effects of increasing stop-jump height on neuromuscular and bio-mechanical properties of knee and ACL, when performed by young female recreational athletes. The underlying hypothesis is increasing stop-jump (platform) height increases knee valgus angles and external moments which also increases ACL strain and internal force. Using numerical analysis tools comprised of Inverse Kinematics, Computed Muscle Control and Forward Dynamics, a novel approach is presented for computing ACL strain and internal force based on (1) knee joint kinematics and (2) optimization of muscle activation, with ACL insertion into musculoskeletal model. Results showed increases in knee valgus external moments and angles with increasing stop-jump height. Increase in stop-jump height from 30 to 50 cm lead to increase in average peak valgus external moment from 40.5 ± 3.2 to 43.2 ± 3.7 Nm which was co-incidental with increase in average peak ACL strain, from 9.3 ± 3.1 to 13.7 ± 1.1%, and average peak ACL internal force, from 1056.1 ± 71.4 to 1165.4 ± 123.8 N for the right side with comparable increases in the left. In effect this study demonstrates a technique for estimating dynamic changes to knee and ACL variables by conducting musculoskeletal simulation on motion analysis data, collected from actual stop-jump tasks performed by young recreational women athletes.

  1. Predictors of Frontal Plane Knee Moments During Side-Step Cutting to 45 and 110 Degrees in Men and Women: Implications for Anterior Cruciate Ligament Injury.

    PubMed

    Sigward, Susan M; Cesar, Guilherme M; Havens, Kathryn L

    2015-11-01

    To compare frontal plane knee moments, and kinematics and kinetics associated with knee valgus moments between cutting to 45 and 110 degrees, and to determine the predictive value of kinematics and ground reaction forces (GRFs) on knee valgus moments when cutting to these angles. Also, to determine whether sex differences exist in kinematics and kinetics when cutting to 45 and 110 degrees. Cross-sectional study. Laboratory setting. Forty-five (20 females) healthy young adult soccer athletes aged 16 to 23 years. Kinematic and kinetic variables were compared between randomly cued side-step cutting maneuvers to 45 and 110 degrees. Predictors of knee valgus moment were determined for each task. Kinematic variables: knee valgus angle, hip abduction, and internal rotation angles. Kinetic variables: vertical, posterior, and lateral GRFs, and knee valgus moment. Knee valgus moments were greater when cutting to 110 degrees compared with 45 degrees, and females exhibited greater moments than males. Vertical and lateral GRFs, hip internal rotation angle, and knee valgus angle explained 63% of the variance in knee valgus moment during cutting to 45 degrees. During cutting to 110 degrees, posterior GRF, hip internal rotation angle, and knee valgus angle explained 41% of the variance in knee valgus moment. Cutting tasks with larger redirection demands result in greater knee valgus moments. Similar factors, including shear GRFs, hip internal rotation, and knee valgus position contribute to knee valgus loading during cuts performed to smaller (45 degrees) and larger (110 degrees) angles. Reducing vertical and shear GRFs during cutting maneuvers may reduce knee valgus moments and thereby potentially reduce risk for anterior cruciate ligament injury.

  2. Evaluating the Quality, Accuracy, and Readability of Online Resources Pertaining to Hallux Valgus.

    PubMed

    Tartaglione, Jason P; Rosenbaum, Andrew J; Abousayed, Mostafa; Hushmendy, Shazaan F; DiPreta, John A

    2016-02-01

    The Internet is one of the most widely utilized resources for health-related information. Evaluation of the medical literature suggests that the quality and accuracy of these resources are poor and written at inappropriately high reading levels. The purpose of our study was to evaluate the quality, accuracy, and readability of online resources pertaining to hallux valgus. Two search terms ("hallux valgus" and "bunion") were entered into Google, Yahoo, and Bing. With the use of scoring criteria specific to hallux valgus, the quality and accuracy of online information related to hallux valgus was evaluated by 3 reviewers. The Flesch-Kincaid score was used to determine readability. Statistical analysis was performed with t tests and significance was determined by P values <.05. Sixty-two unique websites were evaluated. Quality was significantly higher with use of the search term "bunion" as compared to "hallux valgus" (P = .045). Quality and accuracy were significantly higher in resources authored by physicians as compared to nonphysicians (quality, P = .04; accuracy, P < .001) and websites without commercial bias (quality, P = .038; accuracy, P = .011). However, the reading level was significantly more advanced for websites authored by physicians (P = .035). Websites written above an eighth-grade reading level were significantly more accurate than those written at or below an eighth-grade reading level (P = .032). The overall quality of online information related to hallux valgus is poor and written at inappropriate reading levels. Furthermore, the search term used, authorship, and presence of commercial bias influence the value of these materials. It is important for orthopaedic surgeons to become familiar with patient education materials, so that appropriate recommendations can be made regarding valuable resources. Level IV. © 2015 The Author(s).

  3. Increased knee valgus alignment and moment during single-leg landing after overhead stroke as a potential risk factor of anterior cruciate ligament injury in badminton.

    PubMed

    Kimura, Yuka; Ishibashi, Yasuyuki; Tsuda, Eiichi; Yamamoto, Yuji; Hayashi, Yoshimitsu; Sato, Shuichi

    2012-03-01

    In badminton, knees opposite to the racket-hand side received anterior cruciate ligament (ACL) injuries during single-leg landing after overhead stroke. Most of them occurred in the backhand-side of the rear court. Comparing lower limb biomechanics during single-leg landing after overhead stroke between the forehand-side and backhand-side court may help explain the different injury rates depending on court position. The knee kinematics and kinetics during single-leg landing after overhead stroke following back-stepping were different between the forehand-side and backhand-side court. Controlled laboratory study. Hip, knee and ankle joint kinematic and knee kinetic data were collected for 17 right-handed female college badminton players using a 3-dimensional motion analysis system. Subjects performed single-left-legged landing after an overhead stroke following left and right back-stepping. The kinematic and kinetic data of the left lower extremities during landing were measured and compared between left and right back-steps. Hip flexion and abduction and knee valgus at the initial contact, hip and knee flexion and knee valgus at the maximum knee flexion and the maximum knee valgus moment were significantly larger for the left back-step than the right back-step (p<0.05). Significant differences in joint kinematics and kinetics of the lower extremity during single-leg landing after overhead stroke were observed between different back-step directions. Increased knee valgus angle and moment following back-stepping to the backhand-side might be related to the higher incidence of ACL injury during single-leg landing after overhead stroke.

  4. Anthropometric Measurements as Predictors of the Degree of Carrying Angle in College Baseball Players

    ERIC Educational Resources Information Center

    Cox, Chris

    2011-01-01

    Scope and Method of Study: The goal of this study was to examine whether or not height, shoulder range of motion, hip width, shoulder width, and pitching experience were predictors for increased carrying angle of the throwing side. The premise of the study is based on an assumption that valgus extension overload produces tensile strain on the…

  5. Multiobjective optimization of cartilage stress for non-invasive, patient-specific recommendations of high tibial osteotomy correction angle - a novel method to investigate alignment correction.

    PubMed

    Zheng, Keke; Scholes, Corey J; Chen, Junning; Parker, David; Li, Qing

    2017-04-01

    Medial opening wedge high tibial osteotomy (MOWHTO) is a surgical procedure to treat knee osteoarthritis associated with varus deformity. However, the ideal final alignment of the Hip-Knee-Ankle (HKA) angle in the frontal plane, that maximizes procedural success and post-operative knee function, remains controversial. Therefore, the purpose of this study was to introduce a subject-specific modeling procedure in determining the biomechanical effects of MOWHTO alignment on tibiofemoral cartilage stress distribution. A 3D finite element knee model derived from magnetic resonance imaging of a healthy participant was manipulated in-silico to simulate a range of final HKA angles (i.e. 0.2°, 2.7°, 3.9° and 6.6° valgus). Loading and boundary conditions were assigned based on subject-specific kinematic and kinetic data from gait analysis. Multiobjective optimization was used to identify the final alignment that balanced compressive and shear forces between medial and lateral knee compartments. Peak stresses decreased in the medial and increased in the lateral compartment as the HKA was shifted into valgus, with balanced loading occurring at angles of 4.3° and 2.9° valgus for the femoral and tibial cartilage respectively. The concept introduced here provides a platform for non-invasive, patient-specific preoperative planning of the osteotomy for medial compartment knee osteoarthritis. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  6. Location of the Common Peroneal Nerve in Valgus Knees-Is the Reported Safe Zone for Well-Aligned Knees Applicable?

    PubMed

    Yang, Dejin; Shao, Hongyi; Zhou, Yixin; Tang, Hao; Guo, Shengjie

    2017-11-01

    Lateral soft-tissue release can jeopardize the common peroneal nerve (CPN) in total knee arthroplasty for valgus knees. Previous studies reporting safe zones to protect the CPN were based on well-aligned knees. We conducted this study to compare the localization of the CPN in well-aligned knees and in valgus knees. We conducted a consecutive 3-dimensional radiographic study on magnetic resonance images of 58 well-aligned knees and 39 valgus knees. We measured the distance between the CPN and the tibia, as well as the mediolateral, anteroposterior, and angular location of the CPN. We compared the results between well-aligned knees and valgus knees. We found that there is an increased distance between the CPN and the tibia at the level of the tibial cut, but not at the joint line in valgus knees. It is safer to release the posterolateral capsule at the tibial side than at the level above this. The angular location and the mediolateral or anteroposterior location of the CPN in valgus knees are similar to those of well-aligned knees. The location of the CPN in valgus knees is similar to that in well-aligned knees. The previously reported safe zone in well-aligned knees is applicable in valgus knees to protect the CPN. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. History of surgical treatments for hallux valgus.

    PubMed

    Galois, Laurent

    2018-05-31

    In the nineteenth century, the prevalent understanding of the hallux valgus was that it was purely an enlargement of the soft tissue, first metatarsal head, or both, most commonly caused by ill-fitting footwear. Thus, treatment had varying results, with controversy over whether to remove the overlying bursa alone or in combination with an exostectomy of the medial head. Since 1871, when the surgical technique was first described, many surgical treatments for the correction of hallux valgus have been proposed. A number of these techniques have come into fashion, and others have fallen into oblivion. Progress in biomechanical knowledge, and improvements in materials and supports have allowed new techniques to be developed over the years. We have developed techniques that sacrifice the metatarsophalangeal joint (arthrodesis, arthroplasties), as well as conservative procedures, and one can distinguish those which only involve the soft tissues from those that are linked with a first ray osteotomy.

  8. Hallux valgus in a historical French population: paleopathological study of 605 first metatarsal bones.

    PubMed

    Mafart, Bertrand

    2007-03-01

    To estimate the prevalence of hallux valgus in a historical population in France, to identify associated skeletal abnormalities, and to look for an influence of footwear changes through time. We studied the 605 first metatarsals found in the necropolis of the Notre-Dame-du-Bourg cathedral in Digne in the Alpes-de-Hautes-Provence region of southern France. The necropolis contains remains from the 5th to the 17th century. Hallux valgus was identified only in individuals older than 30years at death, and its prevalence increased significantly with age. Exostosis at the medial and dorsal aspects of the head of the first metatarsal were common in advanced forms. The prevalence was comparable in males and females in the Middle Ages but was significantly higher in males in the 16th and 17th centuries, whereas in contemporary populations females are selectively affected. The increase in the prevalence of hallux valgus over time suggests an influence of changes in footwear. The heeled shoes and boots made of stiff leather that men wore in premodern times probably promoted the development of hallux valgus. However, the prevalence of hallux valgus in women in western industrialized countries today is even higher than that in our historical population of older premodern individuals, suggesting an extremely deleterious effect of contemporary female footwear.

  9. L'ostéotomie de scarf dans le traitement de l'hallux valgus: à propos de 19 cas

    PubMed Central

    Boussakri, Hassan; Bachiri, Mohammed; Elidrissi, Mohammed; Shimi, Mohammed; Elibrahimi, Abdelhalim; Elmrini, Abdelmajid

    2014-01-01

    L'ostéotomie de Scarf constitue une technique chirurgicale bien décrite, grâce à ses résultats excellents, elle est considérée comme un traitement de choix de l'hallux valgus. Le but de ce travail est de décrire le profil épidémiologique et radio-clinique des hallux valgus, ainsi qu’évaluer les résultats radiologiques et fonctionnels des patients traités par la technique classique d'ostéotomie de Scarf. Nous avons mené une étude rétrospective, concernant 22 ostéotomies de Scarf chez 19 patients, opérés d'hallux valgus entre mai 2009 et janvier 2013. Le recul moyen était de 22,5 mois (3-42 mois). L'âge moyen des patients au moment de l'intervention était de 49 ans, avec des extrêmes de 19 et 75 ans. Tous les patients ont bénéficié d'une évaluation clinique et radiologique préopératoire et postopératoire ainsi qu'une analyse statistique. Au dernier recul, selon des critères subjectifs, nos résultats étaient très satisfaisants dans 42%, satisfaisants dans 52% et déçus dans 6%, et en fonction du score de l'AOFAS, les résultats étaient nettement améliorée avec un AOFAS préopératoire de 57% à 84% en postopératoire. Concernant les résultats radiologiques, la déformation métatarsophalangienne (angle M1P1) a été corrigée (43,63 °-12,8°) avec une p très significative (p <0,001). D'autre part une amélioration de l'Angle moyen M1M2, passer de 18,18° préopératoire à 12,95° au dernier recul, avec une correction significative (p <0,001). Le valgus épiphysaire de premier métatarsien (AADM) a été statistiquement amélioré (p <0,001), passer de 24,45° à 7,91°. Concernant les complications nous avons noté un cas de sepsis précoce superficiel géré par une antibiothérapie adaptée, deux cas de névrome et un cas d'ostéonécrose. Par contre on n'a pas noté aucune fracture per opératoire du premier métatarsien. Nous concluons que l'ostéotomie de Scarf est une technique reproductible fiable, en pleine

  10. Patient-Directed Valgus Stress Radiograph of the Knee: A New and Novel Technique.

    PubMed

    Mauerhan, David R; Cook, Kyle D; Botts, Tonia D; Williams, Sherita T

    2016-01-01

    The radiographic investigation of patients with medial-compartment osteoarthritis of the knee is a critical element in the decision-making process of determining whether the patient is a candidate for unicompartmental or total knee arthroplasty. A valgus stress radiograph of the affected knee is an essential part of this radiographic investigation. Historically, this has been performed with manual stress applied by the surgeon or the radiologic technologist; thus, this examination requires 2 individuals to complete. In addition to being inefficient, 1 individual is exposed to radiation, which can be undesirable over many exposures and in a long career. For these reasons, we instituted a quality improvement project to develop a method of obtaining the valgus stress view with 1 technologist that would obviate these concerns. Of 78 examinations performed, 5 studies did not show complete correction of the varus deformity. Of these, 3 showed complete correction on a manual valgus stress radiograph, and 2 did not. Three patients displayed collapse of the lateral compartment, indicating a nonfunctional lateral compartment. The remaining 70 patients had identical radiographic results with both the manual and patient-directed valgus stress.

  11. Carpal valgus in llamas and alpacas: Retrospective evaluation of patient characteristics, radiographic features and outcomes following surgical treatment

    PubMed Central

    Hunter, Barbara; Duesterdieck-Zellmer, Katja F.; Huber, Michael J.; Parker, Jill E.; Semevolos, Stacy A.

    2014-01-01

    This study evaluated outcomes of surgical treatment for carpal valgus in New World camelids and correlated successful outcome (absence of carpal valgus determined by a veterinarian) with patient characteristics and radiographic features. Univariable and multivariable analyses of retrospective case data in 19 camelids (33 limbs) treated for carpal valgus between 1987 and 2010 revealed that procedures incorporating a distal radial transphyseal bridge were more likely (P = 0.03) to result in success after a single surgical procedure. A greater degree of angulation (> 19°, P = 0.02) and younger age at surgery (< 4 months, P = 0.03) were associated with unsuccessful outcome. Overall, 74% of limbs straightened, 15% overcorrected, and 11% had persistent valgus following surgical intervention. To straighten, 22% of limbs required multiple procedures, not including implant removal. According to owners, valgus returned following implant removal in 4 limbs that had straightened after surgery. PMID:25477542

  12. Bosch osteotomy and scarf osteotomy for hallux valgus correction.

    PubMed

    Maffulli, Nicola; Longo, Umile Giuseppe; Oliva, Francesco; Denaro, Vincenzo; Coppola, Cristiano

    2009-10-01

    Minimally invasive distal metatarsal osteotomies are becoming broadly accepted for correction of hallux valgus. We compared the duration of surgery, the length of hospital stay, the American Orthopaedic Foot and Ankle Society (AOFAS) score, and the Foot and Ankle Outcome Score (FAOS) in 36 patients who underwent a minimal incision subcapital osteotomy of the first metatarsal with 36 matched patients who had hallux valgus corrected by a scarf technique. The minimum follow-up was 2.1 years (mean, 2.5 years; range, 2.1-3.2 years). Patients having the osteotomy had similar AOFAS and FAOS scores with less operating time and earlier discharge. Less operative time may benefit the patients, and earlier discharge has financial implications for the hospital.

  13. [Surgical technique and clinical results of total knee arthroplasty in treating endstage gonarthrosis combined with valgus knee deformity].

    PubMed

    Wang, Xingshan; Weng, Xisheng; Lin, Jin; Jin, Jin; Qian, Wenwei

    2012-05-01

    To investigate the surgical technique and the clinical results of total knee arthroplasty (TKA) in treating end-stage gonarthrosis combined with valgus knee deformity. Between November 1998 and October 2010, 64 patients (72 knees) with end-stage gonarthrosis combined with valgus knee deformity underwent TKA by a medial parapatellar approach. Of the 64 patients, 18 were male and 46 were female with an average age of 62.5 years (range, 23-82 years), including 44 cases (49 knees) of osteoarthritis, 17 cases (20 knees) of rheumatoid arthritis, 2 cases (2 knees) of haemophilic arthritis, and 1 case (1 knee) of post-traumatic arthritis. Bilateral knees were involved in 8 cases, and single knee in 56 cases. The flexion and extension range of motion (ROM) of the knee joint was (82.2 +/- 28.7) degrees; the femur-tibia angle (FTA) was (18.0 +/- 5.8) degrees; according to Knee Society Score (KSS) criterion, the preoperative clinical score was 31.2 +/- 10.1 and functional score was 37.3 +/- 9.0. According to Krackow's classification, there were 65 knees of type I and 7 knees of type II. By medial parapatellar approach, conventional osteotomy and Ranawat soft tissue release were performed in all cases. Prosthesis of preserved posterior cruciate ligament were used in 7 cases (7 knees), posterior stabilize prosthesis in 54 cases (60 knees), constrained prosthesis in 4 cases (5 knees). Incisions healed by first intention in all cases. Peroneal nerve palsy occurred in 1 patient with haemophilic arthritis, severe valgus deformity (FTA was 41 degrees), and flexion contracture (20 degrees), which was cured after 1 year of conservative treatment. Revison surgery was performed in 1 case of deep infection at 2 years after surgery. All the patients were followed up 4.9 years on average (range, 1-13 years). At last follow-up, the FTA was (7.0 +/- 2.5) degrees, showing significant difference when compared with preoperative value (t = 15.502, P = 0.000). The KSS clinical score was 83.0 +/- 6

  14. Comparison of distal soft-tissue procedures combined with a distal chevron osteotomy for moderate to severe hallux valgus: first web-space versus transarticular approach.

    PubMed

    Park, Yu-Bok; Lee, Keun-Bae; Kim, Sung-Kyu; Seon, Jong-Keun; Lee, Jun-Young

    2013-11-06

    There are two surgical approaches for distal soft-tissue procedures for the correction of hallux valgus-the dorsal first web-space approach, and the medial transarticular approach. The purpose of this study was to compare the outcomes achieved after use of either of these approaches combined with a distal chevron osteotomy in patients with moderate to severe hallux valgus. One hundred and twenty-two female patients (122 feet) who underwent a distal chevron osteotomy as part of a distal soft-tissue procedure for the treatment of symptomatic unilateral moderate to severe hallux valgus constituted the study cohort. The 122 feet were randomly divided into two groups: namely, a dorsal first web-space approach (group D; sixty feet) and a medial transarticular approach (group M; sixty-two feet). The clinical and radiographic results of the two groups were compared at a mean follow-up time of thirty-eight months. The American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot scale hallux metatarsophalangeal-interphalangeal scores improved from a mean and standard deviation of 55.5 ± 12.8 points preoperatively to 93.5 ± 6.3 points at the final follow-up in group D and from 54.9 ± 12.6 points preoperatively to 93.6 ± 6.2 points at the final follow-up in group M. The mean hallux valgus angle in groups D and M was reduced from 32.2° ± 6.3° and 33.1° ± 8.4° preoperatively to 10.5° ± 5.5° and 9.9° ± 5.5°, respectively, at the time of final follow-up. The mean first intermetatarsal angle in groups D and M was reduced from 15.0° ± 2.8° and 15.3° ± 2.7° preoperatively to 6.5° ± 2.2° and 6.3° ± 2.4°, respectively, at the final follow-up. The clinical and radiographic outcomes were not significantly different between the two groups. The final clinical and radiographic outcomes between the two approaches for distal soft-tissue procedures were comparable and equally successful. Accordingly, the results of this study suggest that the medial transarticular

  15. Varus-valgus stability at 90° flexion correlates with the stability at midflexion range more widely than that at 0° extension in posterior-stabilized total knee arthroplasty.

    PubMed

    Hino, Kazunori; Kutsuna, Tatsuhiko; Watamori, Kunihiko; Kiyomatsu, Hiroshi; Ishimaru, Yasumitsu; Takeba, Jun; Watanabe, Seiji; Shiraishi, Yoshitaka; Miura, Hiromasa

    2017-10-01

    Midflexion stability can potentially improve the outcome of total knee arthroplasty (TKA). The purpose of this study was to evaluate the correlation between varus-valgus stability at 0° of extension and 90° of flexion and that at the midflexion range in posterior-stabilized (PS)-TKA. Forty-three knees that underwent PS-TKA were evaluated. Manual mild passive varus-valgus stress was applied to the knees, and the postoperative maximum varus-valgus stability was measured every 10° throughout range of motion, using a navigation system. Correlations between the stability at 0°, 90° of flexion, and that at each midflexion angle were evaluated using Spearman's correlation coefficients. The stability of 0° modestly correlated with that of 10°-20°, but it did not significantly correlate with that of 30°-80°. However, the stability of 90° strongly correlated with that of 60°-80°, modestly correlated with that of 40°-50°, weakly correlated with that of 20°-30°, and did not correlate with that of 10°. The present study confirmed the importance of acquiring stability at 90° flexion to achieve midflexion stability in PS-TKA. However, initial flexion stability did not strongly correlate with the stability at either 0° or 90°. Our findings can provide useful information for understanding varus-valgus stability throughout the range of motion in PS-TKA. Attention to soft tissue balancing is necessary to stabilize a knee at the initial flexion range in PS-TKA.

  16. Increased hallux angle in children and its association with insufficient length of footwear: a community based cross-sectional study.

    PubMed

    Klein, Christian; Groll-Knapp, Elisabeth; Kundi, Michael; Kinz, Wieland

    2009-12-17

    Wearing shoes of insufficient length during childhood has often been cited as leading to deformities of the foot, particularly to the development of hallux valgus disorders. Until now, these assumptions have not been confirmed through scientific research. This study aims to investigate whether this association can be statistically proven, and if children who wear shoes of insufficient length actually do have a higher risk of a more pronounced lateral deviation of the hallux. 858 pre-school children were included in the study. The study sample was stratified by sex, urban/rural areas and Austrian province. The hallux angle and the length of the feet were recorded. The inside length of the children's footwear (indoor shoes worn in pre-school and outdoor shoes) were assessed. Personal data and different anthropometric measurements were taken. The risk of hallux valgus deviation was statistically tested by a stepwise logistic regression analysis and the relative risk (odds ratio) for a hallux angle > or = 4 degrees was calculated. Exact examinations of the hallux angle could be conducted on a total of 1,579 individual feet. Only 23.9% out of 1,579 feet presented a straight position of the great toe. The others were characterized by lateral deviations (valgus position) at different degrees, equalling 10 degrees or greater in 14.2% of the children's feet.88.8% of 808 children examined wore indoor footwear that was of insufficient length, and 69.4% of 812 children wore outdoor shoes that were too short. A significant relationship was observed between the lengthwise fit of the shoes and the hallux angle: the shorter the shoe, the higher the value of the hallux angle. The relative risk (odds ratio) of a lateral hallux deviation of > or = 4 degrees in children wearing shoes of insufficient length was significantly increased. There is a significant relationship between the hallux angle in children and footwear that is too short in length. The fact that the majority of the

  17. Impaired Varus-Valgus Proprioception and Neuromuscular Stabilization in Medial Knee Osteoarthritis

    PubMed Central

    Chang, Alison H.; Lee, Song Joo; Zhao, Heng; Ren, Yupeng; Zhang, Li-Qun

    2014-01-01

    Impaired proprioception and poor muscular stabilization in the frontal plane may lead to knee instability during functional activities, a common complaint in persons with knee osteoarthritis (KOA). Understanding these frontal plane neuromechanical properties in KOA will help elucidate the factors contributing to knee instability and aid in the development of targeted intervention strategies. The study objectives were to compare knee varus-valgus proprioception, isometric muscle strength, and active muscular contribution to stability between persons with medial KOA and healthy controls. We evaluated knee frontal plane neuromechanical parameters in 14 participants with medial KOA and 14 age- and gender-matched controls, using a joint driving device (JDD) with a customized motor and a 6-axis force sensor. Analysis of covariance with BMI as a covariate was used to test the differences in varus-valgus neuromechanical parameters between these two groups. The KOA group had impaired varus proprioception acuity (1.08 ± 0.59° vs. 0.69 ± 0.49°, p < 0.05), decreased normalized varus muscle strength (1.31 ± 0.75% vs. 1.79 ± 0.84% body weight, p < 0.05), a trend toward decreased valgus strength (1.29 ± 0.67% vs. 1.88 ± 0.99%, p = 0.054), and impaired ability to actively stabilize the knee in the frontal plane during external perturbation (4.67 ± 2.86 vs. 8.26 ± 5.95 Nm/degree, p < 0.05). The knee frontal plane sensorimotor control system is compromised in persons with medial KOA. Our findings suggest varus-valgus control deficits in both the afferent input (proprioceptive acuity) and muscular effectors (muscle strength and capacity to stabilize the joint). PMID:24321442

  18. Angle-stable and compressed angle-stable locking for tibiotalocalcaneal arthrodesis with retrograde intramedullary nails. Biomechanical evaluation.

    PubMed

    Mückley, Thomas; Hoffmeier, Konrad; Klos, Kajetan; Petrovitch, Alexander; von Oldenburg, Geert; Hofmann, Gunther O

    2008-03-01

    Retrograde intramedullary nailing is an established procedure for tibiotalocalcaneal arthrodesis. The goal of this study was to evaluate the effects of angle-stable locking or compressed angle-stable locking on the initial stability of the nails and on the behavior of the constructs under cyclic loading conditions. Tibiotalocalcaneal arthrodesis was performed in fifteen third-generation synthetic bones and twenty-four fresh-frozen cadaver legs with use of retrograde intramedullary nailing with three different locking modes: a Stryker nail with compressed angle-stable locking, a Stryker nail with angle-stable locking, and a statically locked Biomet nail. Analyses were performed of the initial stability of the specimens (range of motion) and the laxity of the constructs (neutral zone) in dorsiflexion/plantar flexion, varus/valgus, and external rotation/internal rotation. Cyclic testing up to 100,000 cycles was also performed. The range of motion and the neutral zone in dorsiflexion/plantar flexion at specific cycle increments were determined. In both bone models, the intramedullary nails with compressed angle-stable locking and those with angle-stable locking were significantly superior, in terms of a smaller range of motion and neutral zone, to the statically locked nails. The compressed angle-stable nails were superior to the angle-stable nails only in the synthetic bone model, in external/internal rotation. Cyclic testing showed the nails with angle-stable locking and those with compressed angle-stable locking to have greater stability in both models. In the synthetic bone model, compressed angle-stable locking was significantly better than angle-stable locking; in the cadaver bone model, there was no significant difference between these two locking modes. During cyclic testing, five statically locked nails in the cadaver bone model failed, whereas one nail with angle-stable locking and one with compressed angle-stable locking failed. Regardless of the bone model

  19. Biomechanical effects of valgus knee bracing: a systematic review and meta-analysis.

    PubMed

    Moyer, R F; Birmingham, T B; Bryant, D M; Giffin, J R; Marriott, K A; Leitch, K M

    2015-02-01

    To review and synthesize the biomechanical effects of valgus knee bracing for patients with medial knee osteoarthritis (OA). Electronic databases were searched from their inception to May 2014. Two reviewers independently determined study eligibility, rated study quality and extracted data. Where possible, data were combined into meta-analyses and pooled estimates with 95% confidence intervals (CI) for standardized mean differences (SMD) were calculated. Thirty studies were included with 478 subjects tested while using a valgus knee brace. Various biomechanical methods suggested valgus braces can decrease direct measures of medial knee compressive force, indirect measures representing the mediolateral distribution of load across the knee, quadriceps/hamstring and quadriceps/gastrocnemius co-contraction ratios, and increase medial joint space during gait. Meta-analysis from 17 studies suggested a statistically significant decrease in the external knee adduction moment (KAM) during walking, with a moderate-to-high effect size (SMD = 0.61; 95% CI: 0.39, 0.83; P < 0.001). Meta-regression identified a near-significant association for the KAM effect size and duration of brace use only (β, -0.01; 95% CI: -0.03, 0.0001; P = 0.06); with longer durations of brace use associated with smaller treatment effects. Minor complications were commonly reported during brace use and included slipping, discomfort and poor fit, blisters and skin irritation. Systematic review and meta-analysis suggests valgus knee braces can alter knee joint loads through a combination of mechanisms, with moderate-to-high effect sizes in biomechanical outcomes. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  20. Relationships Between Varus–Valgus Laxity of the Severely Osteoarthritic Knee and Gait, Instability, Clinical Performance, and Function

    PubMed Central

    Freisinger, Gregory M.; Hutter, Erin E.; Lewis, Jacqueline; Granger, Jeffrey F.; Glassman, Andrew H.; Beal, Matthew D.; Pan, Xueliang; Schmitt, Laura C.; Siston, Robert A.; Chaudhari, Ajit M.W.

    2017-01-01

    Increased varus–valgus laxity has been reported in individuals with knee osteoarthritis (OA) compared to controls. However, the majority of previous investigations may not report truly passive joint laxity, as their tests have been performed on conscious participants who could be guarding against motion with muscle contraction during laxity evaluation. The purpose of this study was to investigate how a measure of passive knee laxity, recorded when the participant is under anesthesia, is related to varus–valgus excursion during gait, clinical measures of performance, perceived instability, and self-reported function in participants with severe knee OA. We assessed passive varus–valgus knee laxity in 29 participants (30 knees) with severe OA, as they underwent total knee arthroplasty (TKA). Participants also completed gait analysis, clinical assessment of performance (6-min walk (6 MW), stair climbing test (SCT), isometric knee strength), and self-reported measures of function (perceived instability, Knee injury, and Osteoarthritis Outcome Score (KOOS) a median of 18 days before the TKA procedure. We observed that greater passive varus–valgus laxity was associated with greater varus–valgus excursion during gait (R2 =0.34, p =0.002). Significant associations were also observed between greater laxity and greater isometric knee extension strength (p =0.014), farther 6 MW distance (p =0.033) and shorter SCT time (p =0.046). No relationship was observed between passive varus–valgus laxity and isometric knee flexion strength, perceived instability, or any KOOS subscale. The conflicting associations between laxity, frontal excursion during gait, and functional performance suggest a complex relationship between laxity and knee cartilage health, clinical performance, and self-reported function that merits further study. PMID:27664972

  1. [Treatment of Hallux Valgus: Current Diagnostic Testing and Surgical Treatment Performed by German Foot and Ankle Surgeons].

    PubMed

    Arbab, Dariusch; Schneider, Lisa-Maria; Schnurr, Christoph; Bouillon, Bertil; Eysel, Peer; König, Dietmar Pierre

    2018-04-01

    Hallux valgus is one of the most prevalent foot deformities, and surgical treatment of Hallux valgus is one of the most common procedures in foot and ankle surgery. Diagnostic and treatment standards show large variation despite medical guidelines and national foot and ankle societies. The aim of this nationwide survey is a description of the current status of diagnostics and therapy of Hallux valgus in Germany. A nationwide online questionnaire survey was sent to two German foot and ankle societies. The participants were asked to answer a questionnaire of 53 questions with four subgroups (general, diagnostics, operation, preoperative management). Surgical treatment for three clinical cases demonstrating a mild, moderate and severe Hallux valgus deformity was inquired. 427 foot and ankle surgeons answered the questionnaire. 388 participants were certified foot and ankle surgeons from one or both foot and ankle societies. Medical history (78%), preoperative radiographs (100%) and preoperative radiographic management (78%) are of high or very high importance for surgical decision pathway. Outcome scores are used by less than 20% regularly. Open surgery is still the gold standard, whereas minimally invasive surgery is performed by only 7%. Our survey showed that diagnostic standards are met regularly. There is a wide variation in the type of procedures used to treat Hallux valgus deformity. TMT I arthrodesis is preferred in severe Hallux valgus, but also used to treat moderate and mild deformities. Minimally invasive surgery is still used by a minority of surgeons. It remains to be seen, to what extent minimally invasive surgery will be performed in the future. Georg Thieme Verlag KG Stuttgart · New York.

  2. Long-term results of total knee arthroplasty for valgus knees: soft-tissue release technique and implant selection.

    PubMed

    Rajgopal, Ashok; Dahiya, Vivek; Vasdev, Attique; Kochhar, Hemanshu; Tyagi, Vipin

    2011-04-01

    To report long-term results of total knee arthroplasty (TKA) for valgus knees. 34 women and 19 men aged 39 to 84 (mean, 74) years with valgus knees underwent primary TKA by a senior surgeon. Of the 78 knees, 43, 29, and 6 had type-I, type-II, and type-III valgus deformities, respectively. A preliminary lateral soft-tissue release was performed, and the tibia and femur were prepared. The tight lateral structures were released using the pie-crusting technique. In 92% of the knees, cruciate-retaining implants were used. In knees with severe deformity and medial collateral ligament insufficiency, the posterior cruciate ligament was sacrificed and constrained implants were used. The Hospital for Special Surgery (HSS) knee score was assessed, as were tibiofemoral alignment, range of motion, stability, and evidence of loosening or osteolysis. Patients were followed up for 8 to 14 (mean, 10) years. All knees had a good patellar position and were clinically stable in both mediolateral and anteroposterior planes. No radiolucency was noted. The mean HSS knee score improved from 48 to 91 (p<0.001). The mean tibiofemoral alignment improved from valgus 20 to 5 degrees (p<0.001). The mean range of motion improved from 65 to 110 degrees (p<0.001). One patient developed a deep infection at year 4, and 2 had periprosthetic fractures at years 6 and 8. Adequate lateral soft-tissue release is the key to successful TKAs in valgus knees. The choice of implant depends on the severity of the valgus deformity and the extent of soft-tissue release needed to obtain a stable, balanced flexion and extension gap, in order to achieve minimal constraint with maximum stability.

  3. The effect of repetitive baseball pitching on medial elbow joint space gapping associated with 2 elbow valgus stressors in high school baseball players.

    PubMed

    Hattori, Hiroshi; Akasaka, Kiyokazu; Otsudo, Takahiro; Hall, Toby; Amemiya, Katsuya; Mori, Yoshihisa

    2018-04-01

    To prevent elbow injury in baseball players, various methods have been used to measure medial elbow joint stability with valgus stress. However, no studies have investigated higher levels of elbow valgus stress. This study investigated medial elbow joint space gapping measured ultrasonically resulting from a 30 N valgus stress vs. gravitational valgus stress after a repetitive throwing task. The study included 25 high school baseball players. Each subject pitched 100 times. The ulnohumeral joint space was measured ultrasonographically, before pitching and after each successive block of 20 pitches, with gravity stress or 30 N valgus stress. Two-way repeated measures analysis of variance and Pearson correlation coefficient analysis were used. The 30 N valgus stress produced significantly greater ulnohumeral joint space gapping than gravity stress before pitching and at each successive 20-pitch block (P < .01). For the 2 stress methods, ulnohumeral joint space gapping increased significantly from baseline after 60 pitches (P < .01). Strong significant correlations were found between the 2 methods for measurement of medial elbow joint space gapping (r = 0.727-0.859, P < .01). Gravity stress and 30 N valgus stress may produce different effects with respect to medial elbow joint space gapping before pitching; however, 30 N valgus stress appears to induce greater mechanical stress, which may be preferable when assessing joint instability but also has the potential to be more aggressive. The present results may indicate that constraining factors to medial elbow joint valgus stress matched typical viscoelastic properties of cyclic creep. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  4. Bilateral Carpus Valgus with Cranial Bowing of the Distal Radius in a Foal

    PubMed Central

    Caron, J. P.; Fretz, P. B.; Pharr, J. W.; Bailey, J. V.

    1986-01-01

    Bilateral carpus valgus with concomitant outward rotation and cranial bowing of the distal radii was diagnosed in a crossbred foal. The foal was not lame on admission and showed no radiographic evidence of carpal bone abnormalities. Surgery was limited to the most severely affected leg, and consisted of a combination of growth promotion (periosteal transection and stripping) and temporary physeal retardation (transphyseal bridging) procedures. Correction of the valgus deformity was nearly complete in the operated limb and substantial improvement was observed in the cranial bowing and outward rotation in both limbs, five months postoperatively. ImagesFigure 1.Figure 2. PMID:17422668

  5. Reliability and Validity of Observational Risk Screening in Evaluating Dynamic Knee Valgus

    PubMed Central

    Ekegren, Christina L.; Miller, William C.; Celebrini, Richard G.; Eng, Janice J.; MacIntyre, Donna L.

    2012-01-01

    Study Design Nonexperimental methodological study. Objectives To determine the interrater and intrarater reliability and validity of using observational risk screening guidelines to evaluate dynamic knee valgus. Background A deficiency in the neuromuscular control of the hip has been identified as a key risk factor for non-contact anterior cruciate ligament (ACL) injury in post pubescent females. This deficiency can manifest itself as a valgus knee alignment during tasks involving hip and knee flexion. There are currently no scientifically tested methods to screen for dynamic knee valgus in the clinic or on the field. Methods Three physiotherapists used observational risk screening guidelines to rate 40 adolescent female soccer players according to their risk of ACL injury. The rating was based on the amount of dynamic knee valgus observed on a drop jump landing. Ratings were evaluated for intrarater and interrater agreement using kappa coefficients. Sensitivity and specificity of ratings were evaluated by comparing observational ratings with measurements obtained using 3-dimensional (3D) motion analysis. Results Kappa coefficients for intrarater and interrater agreement ranged from 0.75 to 0.85, indicating that ratings were reasonably consistent over time and between physiotherapists. Sensitivity values were inadequate, ranging from 67–87%. This indicated that raters failed to detect up to a third of “truly high risk” individuals. Specificity values ranged from 60–72% which was considered adequate for the purposes of the screen. Conclusion Observational risk screening is a practical and cost-effective method of screening for ACL injury risk. Rater agreement and specificity were acceptable for this method but sensitivity was not. To detect a greater proportion of individuals at risk of ACL injury, coaches and clinicians should ensure that they include additional tests for other high risk characteristics in their screening protocols. PMID:19721212

  6. Footwear modification following hallux valgus surgery: The all-or-none phenomenon.

    PubMed

    Robinson, Cal; Bhosale, Abhijit; Pillai, Anand

    2016-06-26

    To define footwear outcomes following hallux valgus surgery, focusing on patient return to comfortable and heeled footwear and patterns of post-operative footwear selection. Surgical intervention is indicated for symptomatic cases of hallux valgus unresponsive to conservative methods, with favourable reported outcomes. The return to various types of footwear post-operatively is reflective of the degree of correction achieved, and corresponds to patient satisfaction. Patients are expected to return to comfortable footwear post-operatively without significant residual symptoms. Many female patients will additionally attempt to return to high-heeled, narrow toe box shoes. However, minimal evidence exists to guide their expectations. Sixty-five female hallux valgus patients that had undergone primary surgery between 2011 and 2013 were retrospectively identified using our hospital surgical database. Patients were reviewed using a footwear-specific outcome questionnaire at a mean 18.5 mo follow-up. Eighty-six percent of patients were able to return to comfortable footwear post-operatively with minimal discomfort. Of those intending to resume wearing heeled footwear, 62% were able to do so, with 77% of these patients wearing these as or more frequently than pre-operatively. No significant difference was observed between pre- and post-operative heel size. Mean time to return to heeled footwear was 21.4 wk post-operation. Cosmetic outcomes were very high and did not adversely impact footwear selection. We report high rates of return to both comfortable and heeled shoes in female patients following primary hallux valgus surgery. We observed an "all-or-none phenomenon" where patients rejected a return to heeled footwear unless able to tolerate them at the same frequency and heel size as pre-operatively. A minority of patients were unable to return to comfortable footwear post-operatively, which had adverse ramifications on their quality-of-life. We recommend that the

  7. Footwear modification following hallux valgus surgery: The all-or-none phenomenon

    PubMed Central

    Robinson, Cal; Bhosale, Abhijit; Pillai, Anand

    2016-01-01

    AIM: To define footwear outcomes following hallux valgus surgery, focusing on patient return to comfortable and heeled footwear and patterns of post-operative footwear selection. METHODS: Surgical intervention is indicated for symptomatic cases of hallux valgus unresponsive to conservative methods, with favourable reported outcomes. The return to various types of footwear post-operatively is reflective of the degree of correction achieved, and corresponds to patient satisfaction. Patients are expected to return to comfortable footwear post-operatively without significant residual symptoms. Many female patients will additionally attempt to return to high-heeled, narrow toe box shoes. However, minimal evidence exists to guide their expectations. Sixty-five female hallux valgus patients that had undergone primary surgery between 2011 and 2013 were retrospectively identified using our hospital surgical database. Patients were reviewed using a footwear-specific outcome questionnaire at a mean 18.5 mo follow-up. RESULTS: Eighty-six percent of patients were able to return to comfortable footwear post-operatively with minimal discomfort. Of those intending to resume wearing heeled footwear, 62% were able to do so, with 77% of these patients wearing these as or more frequently than pre-operatively. No significant difference was observed between pre- and post-operative heel size. Mean time to return to heeled footwear was 21.4 wk post-operation. Cosmetic outcomes were very high and did not adversely impact footwear selection. CONCLUSION: We report high rates of return to both comfortable and heeled shoes in female patients following primary hallux valgus surgery. We observed an “all-or-none phenomenon” where patients rejected a return to heeled footwear unless able to tolerate them at the same frequency and heel size as pre-operatively. A minority of patients were unable to return to comfortable footwear post-operatively, which had adverse ramifications on their quality

  8. Impact of Podiatry Resident Experience Level in Hallux Valgus Surgery on Postoperative Outcomes

    PubMed Central

    Fleischer, Adam E.; Yorath, Martin C.; Joseph, Robert; Baron, Adam; Nordquist, Thomas; Moore, Braden; Robinson, Richmond; Reilly, Charles

    2018-01-01

    Background Despite modern advancements in transosseous fixation and operative technique, hallux valgus (i.e., bunion) surgery is still associated with a higher than usual amount of patient dissatisfaction, and is generally recognized as a complex and nuanced procedure requiring precise osseous and capsulotendon balancing. It stands to reason then that familiarity and skill level of trainee surgeons might impact surgical outcomes in this surgery. The aim of this study was to determine whether podiatry resident experience level influences mid-term outcomes in hallux valgus surgery. Methods Consecutive adults who underwent isolated hallux valgus surgery via distal metatarsal osteotomy at a single US metropolitan teaching hospital from January 2004 to January 2009 were contacted and asked to complete a validated outcome measure of foot health (Manchester-Oxford Foot Questionnaire) regarding their operated foot. Resident experience level was quantified using the surgical logs for the primary resident of record at the time of each case. Associations were assessed using simple, multiple and logistic regression analyses. Results A total of 102 adult patients (n=102 feet) agreed to participate with a mean age of 46.8 (SD 13.1 years, range 18-71) and average length of follow-up 6.2 years (SD 1.4, range 3.6-8.6). Level of trainee experience was not associated with postoperative outcomes in either the univariate (odds ratio 0.99 [95% CI 0.98-1.01], p = 0.827) or multivariate analyses (odds ratio 1.00 [95% CI 0.97-1.02], p = 0.907). Conclusions We conclude that podiatry resident level of experience in hallux valgus surgery does not contribute appreciably to postoperative clinical outcomes. PMID:24726058

  9. Operative Treatment of Traumatic Hallux Valgus in Elite Athletes.

    PubMed

    Covell, D Jeff; Lareau, Craig R; Anderson, Robert B

    2017-06-01

    Traumatic hallux valgus is an increasingly common injury in the athletic population and represents a unique variant of turf toe. Failure to appropriately recognize and treat these injuries can lead to continued pain, decreased performance, progressive deformities, and ultimately degeneration of the hallux metatarsophalangeal joint. Limited literature currently exists to assist in the diagnosis, management, and operative treatment. Nineteen patients were reviewed in this series, including 12 National Football League, 6 college, and 1 high school player who was a college prospect. The average age for all patients at the time of surgery was 24.4 years (range, 19-33 years). Return to play and complications were evaluated. Overall, good operative results were obtained, with 74% of patients returning to their preinjury level of play at an average recovery time of 3.4 months. Traumatic hallux valgus is an increasingly common injury in the athletic population and represents a unique variant of turf toe. The impact of this injury cannot be overstated, as one-quarter of players were unable to return to play. Level IV, case series.

  10. Proximal opening wedge osteotomy with wedge-plate fixation compared with proximal chevron osteotomy for the treatment of hallux valgus: a prospective, randomized study.

    PubMed

    Glazebrook, Mark; Copithorne, Peter; Boyd, Gordon; Daniels, Timothy; Lalonde, Karl-André; Francis, Patricia; Hickey, Michael

    2014-10-01

    Hallux valgus with an increased intermetatarsal angle is usually treated with a proximal metatarsal osteotomy. The proximal chevron osteotomy is commonly used but is technically difficult. This study compares the proximal opening wedge osteotomy of the first metatarsal with the proximal chevron osteotomy for the treatment of hallux valgus with an increased intermetatarsal angle. This prospective, randomized multicenter (three-center) study was based on the clinical outcome scores of the Short Form-36, the American Orthopaedic Foot & Ankle Society forefoot questionnaire, and the visual analog scale for pain, activity, and patient satisfaction. Subjects were assessed prior to surgery and at three, six, and twelve months postoperatively. Surgeon preference was evaluated based on questionnaires and the operative times required for each procedure. No significant differences were found for any of the patients' clinical outcome measurements between the two procedures. The proximal opening wedge osteotomy was found to lengthen, and the proximal chevron osteotomy was found to shorten, the first metatarsal. The intermetatarsal angles improved (decreased) significantly, from 14.8° ± 3.2° to 9.1° ± 2.9 (mean and standard deviation) after a proximal opening wedge osteotomy and from 14.6° ± 3.9° to 11.3° ± 4.0° after a proximal chevron osteotomy (p < 0.05 for both). Operative time required for performing a proximal opening wedge osteotomy is similar to that required for performing a proximal chevron osteotomy (mean and standard deviation, 67.1 ± 16.5 minutes compared with 69.9 ± 18.6 minutes; p = 0.510). Opening wedge and proximal chevron osteotomies have comparable radiographic outcomes and comparable clinical outcomes for pain, satisfaction, and function. The proximal opening wedge osteotomy lengthens, and the proximal chevron osteotomy shortens, the first metatarsal. The proximal opening wedge osteotomy was subjectively less technically demanding and was

  11. Combined versus individual effects of a valgus knee brace and lateral wedge foot orthotic during stair use in patients with knee osteoarthritis.

    PubMed

    Moyer, Rebecca; Birmingham, Trevor; Dombroski, Colin; Walsh, Robert; Giffin, J Robert

    2017-05-01

    The aim of this study was to investigate the combined and individual biomechanical effects of a valgus knee brace and a lateral wedge foot orthotic during stair ascent and descent in patients with knee osteoarthritis (OA). Thirty-five patients with varus alignment and medial knee OA were prescribed a custom valgus knee brace and lateral wedge foot orthotic. Knee angles and moments in the frontal and sagittal planes were determined from 3D gait analysis completed under four randomized conditions: (1) control (no knee brace or foot orthotic), (2) knee brace, (3) foot orthotic, and (4) combined knee brace and foot orthotic. Additional measures included the vertical ground reaction force, trunk lean, toe out and gait speed. During the combined use of a knee brace and foot orthotic, significant decreases in the knee adduction angle (2.17, 95%CI: 0.50-3.84, p=0.013) and 2nd peak EKAM (0.35, 95%CI: 0.17-0.52, p<0.001) were observed during stair descent; and significant increases in the EKFM were observed during stair ascent (0.54, 95%CI: 0.30-0.78, p<0.001) and descent (1stpk: 0.48, 95%CI: 0.15-0.80, p=0.005; 2ndpk: 0.55, 95%CI: 0.34-0.76, p<0.001). Fewer gait compensations were observed between conditions during stair descent compared to ascent, except for toe out. Findings suggest greater effects on gait when both knee brace and foot orthotic are used together, resulting in a more normal gait pattern. However, whether or not a true change in knee joint load can be inferred when using these orthoses remains unclear. Further research is required to determine the clinical importance of the observed changes. Copyright © 2017. Published by Elsevier B.V.

  12. Does the type of sport practised influence foot posture and knee angle? Differences between footballers and swimmers.

    PubMed

    Lopezosa-Reca, Eva; Gijon-Nogueron, Gabriel; Garcia-Paya, Irene; Ortega-Avila, Ana Belen

    2018-03-04

    This aim of this study is to observe the differences in foot posture and the angle of the knee according to different physical activities. Seventy-eight football players and 72 swimmers were recruited, and in each case a foot posture analysis, based on the foot posture index (FPI), was conducted and the Q angle of the knee was determined. The following mean values were obtained for the lower extremities: in the swimmers, FPI 6.45 ± 2.04 and Q angle 15.38º ± 3.79º. In the footballers, FPI 2.23 ± 1.72 and Q angle 13.16º ± 1.36º. There were statistically significant differences (p < 0.001) between the two groups. The swimmers presented a foot posture with a tendency towards pronation, and a Q angle with a tendency towards valgus, while the results for the footballers were within the normal range.

  13. Should the Ipsilateral Hamstrings Be Used for Anterior Cruciate Ligament Reconstruction in the Case of Medial Collateral Ligament Insufficiency? Biomechanical Investigation Regarding Dynamic Stabilization of the Medial Compartment by the Hamstring Muscles.

    PubMed

    Herbort, Mirco; Michel, Philipp; Raschke, Michael J; Vogel, Nils; Schulze, Martin; Zoll, Alexander; Fink, Christian; Petersen, Wolf; Domnick, Christoph

    2017-03-01

    Semitendinosus and gracilis muscles are frequently harvested for autologous tendon grafts for cruciate ligament reconstruction. This study investigated the joint-stabilizing effects of these hamstring muscles in cases of insufficiency of the medial collateral ligament (MCL). First, both the semitendinosus and gracilis muscles can actively stabilize the joint against valgus moments in the MCL-deficient knee. Second, the stabilizing influence of these muscles decreases with an increasing knee flexion angle. Controlled laboratory study. The kinematics was examined in 10 fresh-frozen human cadaveric knees using a robotic/universal force moment sensor system and an optical tracking system. The knee kinematics under 5- and 10-N·m valgus moments were determined in the different flexion angles of the (1) MCL-intact and (2) MCL-deficient knee using the following simulated muscle loads: (1) 0-N (idle) load, (2) 200-N semitendinosus (ST) load, and (3) 280-N (200/80-N) combined semitendinosus/gracilis (STGT) load. Cutting the MCL increased the valgus angle under all tested conditions and angles compared with the MCL-intact knee by 4.3° to 8.1° for the 5-N·m valgus moment and 6.5° to 11.9° for the 10-N·m valgus moment ( P < .01). The applied 200-N simulated ST load reduced the valgus angle significantly at 0°, 10°, 20°, and 30° of flexion under 5- and 10-N·m valgus moments ( P < .05). At 0°, 10°, and 20° of flexion, these values were close to those for the MCL-intact joint under the respective moments (both P > .05). The combined 280-N simulated STGT load significantly reduced the valgus angle in 0°, 10°, and 20° of flexion under 5- and 10-N·m valgus moments ( P < .05) to values near those for the intact joint (5 N·m: 0°, 10°; 10 N·m: 0°, 10°, 20°; P > .05). In 60° and 90° of flexion, ST and STGT loads did not decrease the resulting valgus angle of the MCL-deficient knee without hamstring loads ( P > .05 vs deficient; P = .0001 vs intact). In this

  14. Correction of static axial alignment in children with knee varus or valgus deformities through guided growth: Does it also correct dynamic frontal plane moments during walking?

    PubMed

    Böhm, Harald; Stief, Felix; Sander, Klaus; Hösl, Matthias; Döderlein, Leonhard

    2015-09-01

    Malaligned knees are predisposed to the development and progression of unicompartmental degenerations because of the excessive load placed on one side of the knee. Therefore, guided growth in skeletally immature patients is recommended. Indication for correction of varus/valgus deformities are based on static weight bearing radiographs. However, the dynamic knee abduction moment during walking showed only a weak correlation to malalignment determined by static radiographs. Therefore, the aim of the study was to measure the effects of guided growth on the normalization of frontal plane knee joint moments during walking. 15 legs of 8 patients (11-15 years) with idiopathic axial varus or valgus malalignment were analyzed. 16 typically developed peers served as controls. Instrumented gait analysis and clinical assessment were performed the day before implantation and explantation of eight-plates. Correlation between static mechanical tibiofemoral axis angle (MAA) and dynamic frontal plane knee joint moments and their change by guided growth were performed. The changes in dynamic knee moment in the frontal plane following guided growth showed high and significant correlation to the changes in static MAA (R=0.97, p<0.001). Contrary to the correlation of the changes, there was no correlation between static and dynamic measures in both sessions. In consequence two patients that had a natural knee moment before treatment showed a more pathological one after treatment. In conclusion, the changes in the dynamic load situation during walking can be predicted from the changes in static alignment. If pre-surgical gait analysis reveals a natural load situation, despite a static varus or valgus deformity, the intervention must be critically discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. [Preemptive local anesthetic infiltration in hallux valgus one-day surgery].

    PubMed

    Gądek, Artur; Liszka, Henryk

    2015-01-01

    The surgical treatment of hallux valgus deformity is connected with significant postoperative pain. Spinal and general anesthesia as well as peripheral blocks are successfully used in foot surgery. The purpose of this study was to evaluate the influence of local anesthetic infiltration before hallux valgus one-day surgery on postoperative pain and the need for analgesics. 134 patients underwent chevron or miniinvasive Mitchell-Kramer osteotomy of the first distal metatarsal. After general anesthesia each patient randomly received an infiltration of 7ml of local anesthetic (4 ml of 0.25% bupivacaine and 3 ml of 2% lidocaine) or the same amount of normal saline 15 minutes before the skin incision. Both the patient and the surgeon were blinded. The patient was discharged after approximately 2 hours of observation. 2, 4, 8, 12, 16, 24 and 72 hours after the release of the tourniquet the level of pain was assessed by the visual analogue scale (VAS). Rescue analgesia, side effects and the use of painkillers were noted. Preemptive local anesthetic infiltration significantly decreased pain during the first 24 hours after the surgery. None of the patients from the injected group and 38 from the placebo group received 100 mg of ketoprofen intravenously for rescue analgesia in the first 2 hours after the release of the tourniquet. During the first 24 hours we noted significantly decreased use of 1000 mg of paracetamol and 100 mg mg of ketoprofen orally in the injected group. No systemic adverse effects were noted. One patient from placebo group had allergic rush after use of 100 mg ketoprofen. Preemptive local anesthetic infiltration in one-day hallux valgus surgery significantly decreases postoperative pain. It is safe, efficient and allows fast discharge.

  16. The Valgus Inclination of the Tibial Component Increases the Risk of Medial Tibial Condylar Fractures in Unicompartmental Knee Arthroplasty.

    PubMed

    Inoue, Shinji; Akagi, Masao; Asada, Shigeki; Mori, Shigeshi; Zaima, Hironori; Hashida, Masahiko

    2016-09-01

    Medial tibial condylar fractures (MTCFs) are a rare but serious complication after unicompartmental knee arthroplasty. Although some surgical pitfalls have been reported for MTCFs, it is not clear whether the varus/valgus tibial inclination contributes to the risk of MTCFs. We constructed a 3-dimensional finite elemental method model of the tibia with a medial component and assessed stress concentrations by changing the inclination from 6° varus to 6° valgus. Subsequently, we repeated the same procedure adding extended sagittal bone cuts of 2° and 10° in the posterior tibial cortex. Furthermore, we calculated the bone volume that supported the tibial component, which is considered to affect stress distribution in the medial tibial condyle. Stress concentrations were observed on the medial tibial metaphyseal cortices and on the anterior and posterior tibial cortices in the corner of cut surfaces in all models; moreover, the maximum principal stresses on the posterior cortex were larger than those on the anterior cortex. The extended sagittal bone cuts in the posterior tibial cortex increased the stresses further at these 3 sites. In the models with a 10° extended sagittal bone cut, the maximum principal stress on the posterior cortex increased as the tibial inclination changed from 6° varus to 6° valgus. The bone volume decreased as the inclination changed from varus to valgus. In this finite element method, the risk of MTCFs increases with increasing valgus inclination of the tibial component and with increased extension of the sagittal cut in the posterior tibial cortex. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Observed changes in radiographic measurements of the first ray after frontal plane rotation of the first metatarsal in a cadaveric foot model.

    PubMed

    Dayton, Paul; Feilmeier, Mindi; Hirschi, Jordan; Kauwe, Merrell; Kauwe, John S K

    2014-01-01

    We observed the changes in the angular measurements commonly used in the evaluation of the first metatarsal and first metatarsophalangeal joint in cadaveric specimens before and after frontal plane rotation of the first metatarsal. Measurements of the first and second intermetatarsal angle (IMA), hallux abductus angle, proximal articular set angle, and tibial sesamoid position (TSP) were taken after varying degrees of varus and valgus rotation of the first metatarsal. Standard dorsoplantar radiographs were taken at 0°, 10°, 20°, and 30° of valgus rotation of the first metatarsal and repeated at 10°, 20°, and 30° varus rotation of the first metatarsal. The data were analyzed using a mixed linear model to compare the change in each angle measurement over the range of valgus and varus rotation. The change in the TSP was significant in both valgus and varus rotations (p = .0004 and p = .028, respectively), an increase in valgus rotation causing an increase in the TSP and an increase in varus rotation causing a decrease in TSP. The change in the IMA was significant compared with valgus rotation (p = .028), showing that as the valgus rotation increased, the IMA also increased. However, compared with the varus rotation, the correlation was not significant (p = .18). The proximal articular set angle and hallux abductus angle measurements, compared with metatarsal rotation, showed positive trends but were not statistically significant. From our results and a review of the published data, we have hypothesized that frontal plane rotation of the first metatarsal is an integral component of hallux abducto valgus pathologic features, specifically in relation to the TSP and IMA. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Medial Elbow Joint Space Increases With Valgus Stress and Decreases When Cued to Perform A Maximal Grip Contraction.

    PubMed

    Pexa, Brett S; Ryan, Eric D; Myers, Joseph B

    2018-04-01

    Previous research indicates that the amount of valgus torque placed on the elbow joint during overhead throwing is higher than the medial ulnar collateral ligament (UCL) can tolerate. Wrist and finger flexor muscle activity is hypothesized to make up for this difference, and in vitro studies that simulated activity of upper extremity musculature, specifically the flexor digitorum superficialis and flexor carpi ulnaris, support this hypothesis. To assess the medial elbow joint space at rest, under valgus stress, and under valgus stress with finger and forearm flexor contraction by use of ultrasonography in vivo. Controlled laboratory study. Participants were 22 healthy males with no history of elbow dislocation or UCL injury (age, 21.25 ± 1.58 years; height, 1.80 ± 0.08 m; weight, 79.43 ± 18.50 kg). Medial elbow joint space was measured by use of ultrasonography during 3 separate conditions: at rest (unloaded), under valgus load (loaded), and with a maximal grip contraction under a valgus load (loaded-contracted) in both limbs. Participants lay supine with their arm abducted 90° and elbow flexed 30° with the forearm in full supination. A handgrip dynamometer was placed in the participants' hand to grip against during the contracted condition. Images were reduced in ImageJ to assess medial elbow joint space. A 2-way (condition × limb) repeated-measures analysis of variance and Cohen's d effect sizes were used to assess changes in medial elbow joint space. Post hoc testing was performed with a Bonferroni adjustment to assess changes within limb and condition. The medial elbow joint space was significantly larger in the loaded condition (4.91 ± 1.16 mm) compared with the unloaded condition (4.26 ± 1.23 mm, P < .001, d = 0.712) and the loaded-contracted condition (3.88 ± 0.94 mm, P < .001, d = 1.149). No significant change was found between the unloaded and loaded-contracted conditions ( P = .137). Medial elbow joint space increases under a valgus load and then

  19. Perioperative analgesia with a buprenorphine transdermal patch for hallux valgus surgery: a prospective, randomized, controlled study

    PubMed Central

    Xu, Can; Li, Mingqing; Wang, Chenggong; Li, Hui; Liu, Hua

    2018-01-01

    Purpose Hallux valgus surgery often results in significant postoperative pain. Adequate control of pain is essential for patient satisfaction and improves the outcome of the procedure. This study aimed to investigate the perioperative analgesic effect of a buprenorphine transdermal patch in patients who underwent hallux valgus surgery. Patients and methods A total of 90 patients were randomly divided into the following three groups based on the perioperative analgesic method: flurbiprofen axetil intravenous injection (Group F), oral celecoxib (Group C), and buprenorphine transdermal delivery system (BTDS) (Group BTDS). The pain status, degree of satisfaction, adverse effects, and administration of tramadol hydrochloride for uncontrolled pain were recorded on the night before surgery, postoperative day 1, postoperative day 2, and postoperative day 3. Results The BTDS could effectively control perioperative pain for patients undergoing hallux valgus surgery. The analgesic effect of the BTDS was better than that of oral celecoxib. In addition, statistically significant differences were not observed in the visual analog scale (VAS) scores, adverse effects, and rescue analgesia between the patients who received the BTDS and the patients who received the flurbiprofen axetil intravenous injection. However, the degree of patient satisfaction of the BTDS group was significantly higher (P<0.05) than that of the other two groups. Conclusion The BTDS (a preemptive analgesia regimen) could exert an analgesic effect during the perioperative period for patients who had received hallux valgus surgery, and this effect is beneficial for sustaining postoperative physiological and psychological states and promoting functional rehabilitation. PMID:29731664

  20. Prospective randomized study of chevron osteotomy versus Mitchell's osteotomy in hallux valgus.

    PubMed

    Buciuto, Robert

    2014-12-01

    We conducted a prospective randomized trial to compare the most popular osteotomy types of operative treatment of hallux valgus (HV) used in Norway, Mitchell's osteotomy (MO) and chevron osteotomy (CO). One hundred twenty adult female patients were prospectively randomized to treatment with either MO or CO. All operative procedures were performed with ankle block and with tourniquet applied. None of the patients received any antibiotic or antithrombotic prophylaxis. The follow-up period was 3 years. Clinical results were rated according to the American Orthopaedic Foot and Ankle Society (AOFAS) Clinical Rating System (CRS). HV in the MO group was reduced from 30 (range, 20 to 44) to 15 (range, 8 to 24) degrees and IM angle from 11 (range, 6 to 14) to 7 (range, 4 to 11) degrees. HV in the CO group was reduced from 31 (range, 22 to 42) to 16 (range, 6 to 24) degrees and IM angle from 14 (range, 8 to 20) to 6 (range, 2 to 10) degrees. Transfer metatarsalgia occurred in 36 (60%) patients and hammertoe in 6 (10%) patients in the MO group. In the CO group, metatarsalgia occurred in 5 patients. The median loss of postoperative HV correction was 4 (range, 2 to 10) degrees in mild deformity and 6 (6 to 10) degrees in moderate deformity. Patients treated with CO had significantly better results for AOFAS CRS, number of postoperative complications, patient satisfaction, and length of sick leave for the employed patients. Based on our results, we consider that in female patients CO should be regarded as the first-line procedure for treatment of mild and moderate HV. Level I, prospective randomized study. © The Author(s) 2014.

  1. Dynamic knee valgus alignment influences impact attenuation in the lower extremity during the deceleration phase of a single-leg landing.

    PubMed

    Tamura, Akihiro; Akasaka, Kiyokazu; Otsudo, Takahiro; Shiozawa, Jyunya; Toda, Yuka; Yamada, Kaori

    2017-01-01

    Dynamic knee valgus during landings is associated with an increased risk of non-contact anterior cruciate ligament (ACL) injury. In addition, the impact on the body during landings must be attenuated in the lower extremity joints. The purpose of this study was to investigate landing biomechanics during landing with dynamic knee valgus by measuring the vertical ground reaction force (vGRF) and angular impulses in the lower extremity during a single-leg landing. The study included 34 female college students, who performed the single-leg drop vertical jump. Lower extremity kinetic and kinematic data were obtained from a 3D motion analysis system. Participants were divided into valgus (N = 19) and varus (N = 15) groups according to the knee angular displacement during landings. The vGRF and angular impulses of the hip, knee, and ankle were calculated by integrating the vGRF-time curve and each joint's moment-time curve. vGRF impulses did not differ between two groups. Hip angular impulse in the valgus group was significantly smaller than that in the varus group (0.019 ± 0.033 vs. 0.067 ± 0.029 Nms/kgm, p<0.01), whereas knee angular impulse was significantly greater (0.093 ± 0.032 vs. 0.045 ± 0.040 Nms/kgm, p<0.01). There was no difference in ankle angular impulse between the groups. Our results indicate that dynamic knee valgus increases the impact the knee joint needs to attenuate during landing; conversely, the knee varus participants were able to absorb more of the landing impact with the hip joint.

  2. Trampoline fracture of the proximal tibial metaphysis in children may not progress into valgus: a report of seven cases and a brief review.

    PubMed

    Kakel, R

    2012-06-01

    Fracture of the proximal tibial metaphysis in children is a rare injury but notorious for carrying the risk of subsequent valgus deformity of the tibia. Trampoline-caused fracture of the proximal tibial metaphysis in children may not progress into valgus. We followed up six children who collectively sustained seven fractures of the proximal tibial metaphysis while trampolining with other heavier and/or older children. Initial and follow-up x-rays were reviewed by an orthopaedic surgeons and two radiologists. None of the patients developed valgus deformity with follow-up. Trampoline is associated with a specific type of injury to the proximal tibia when children are trampolining with other heavier children even without falling off the trampoline. This fracture is linear and complete, often non-displaced. Unlike "other" proximal tibial metaphyseal fractures, trampoline-associated proximal tibial metaphysical fracture in children is not associated with a risk of subsequent valgus deformity. Level 4. case series. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  3. Tensile Properties of the Deep Transverse Metatarsal Ligament in Hallux Valgus: A CONSORT-Compliant Article.

    PubMed

    Abdalbary, Sahar Ahmed; Elshaarawy, Ehab A A; Khalid, Bahaa E A

    2016-02-01

    The deep transverse metatarsal ligament (DTML) connects the neighboring2 metatarsal heads and is one of the stabilizers connecting the lateral sesamoid and second metatarsal head. In this study, we aimed to determine the tensile properties of the DTML in normal specimens and to compare these results with hallux valgus specimens. We hypothesized that the tensile properties of the DTML would be different between the 2 groups of specimens.The DTML in the first interspace was dissected from 12 fresh frozen human cadaveric specimens. Six cadavers had bilateral hallux valgus and the other 6 cadavers had normal feet. The initial length (L0) and cross-sectional area (A0) of the DTML were measured using a digital caliper, and tensile tests with load failure were performed using a material testing machine.There were significant between-groups differences in the initial length (L0) P = 0.009 and cross-sectional area (A0) of the DTML P = 0.007. There were also significant between-groups differences for maximum force (N) P = 0.004, maximum distance (mm) P = 0.005, maximum stress (N/mm) P = 0.003, and maximum strain (%) P = 0.006.The DTML is an anatomical structure for which the tensile properties differ in hallux valgus.

  4. Triple management of cubitus valgus deformity complicating neglected nonunion of fractures of lateral humeral condyle in children: a case series.

    PubMed

    Abed, Yasser; Nour, Khaled; Kandil, Yasser Roshdy; El-Negery, Abed

    2018-02-01

    Long standing nonunion of the lateral humeral condyle (LHC) usually results in elbow pain and instability with progressive cubitus valgus and tardy ulnar neuritis. Surgical treatment of long standing nonunion is still a controversial issue due to the reported complications, such as stiffness, loss of elbow motion, and avascular necrosis of the LHC fragment. In this study, we reported the outcomes of treatment of cubitus valgus deformity in long standing nonunion of the LHC in children treated with combined triple management (fixation of the nonunion site, dome corrective osteotomy, and anterior transposition of ulnar nerve) through a modified para-triceptal approach. We evaluated ten patients with cubitus valgus deformity more than 20 degrees after neglected nonunion of the lateral humeral condyle more than 24 months. Only childern with post-operative follow up more than 24 months were included in this study. All patients were evaluated clinically, radio logically, and by pre- and post-operative functional evaluation using Mayo elbow performance score. For evaluation of ulnar nerve affection, the Akahori's system was used. There were six females and four males with the average age of 7.7 years at operation. The left elbow was affected in six patients and the right elbow was affected in four patients. The average time between fracture of the LHC and operation was 40.3 months with average post-operative follow up of 44.3 months. The average carrying angle of the healthy side was 5.5 degrees and pre-operative carrying angle of the affected side was 33.5 degrees. The average post-operative carrying angle of the affected side was 6.1 degrees. The improvement of the carrying angle at the last follow up was found statistically significant (p < 0.05). All six patients that had pre-operative various degrees of ulnar nerve affection had completely improved at last follow up. The osteotomy site united in an average time of 43 days, whereas the LHC nonunion site

  5. Management of pain on hallux valgus with percutaneous intra-articular Pulse-Dose Radiofrequency.

    PubMed

    Masala, Salvatore; Fiori, Roberto; Calabria, Eros; Raguso, Mario; de Vivo, Dominique; Cuzzolino, Alessandro; Simonetti, Giovanni

    2017-01-01

    The purpose of our study was to investigate the role of intra-articular pulse-dose radiofrequency in management of painful hallux valgus refractory to conservative therapies. Between November 2010 and April 2012, 51 patients (15 male, 36 female) with a median age of 71.4 years were included in our clinical trial. Under fluoroscopic guidance we introduced a 22 gauge 10 cm length cannula by a percutaneous access in the first metatarsophalangeal joint and its tip was placed intra-articularly. After removing the spindle, a radiofrequency needle with a 5 mm active tip was introduced. The following parameters were used: 1200 pulses at high voltage (45 V) with 20 msec duration followed by 480 msec silent phases. A great reduction in pain intensity was documented at 1 week, 1 month and 3 months after procedures. Pain intensity increased between 5 and 8 months after treatments, so we performed a second procedure in all patients between 7 months and 9 months since the first treatment. Also in this case we obtained a great reduction of pain intensity in the first 3 months after the procedure. Pain intensity returned at preprocedural values after 9 months after second procedure. No complications were observed. Our experience shows pulse-dose radiofrequency is a safe, repeatable and effective technique for managing patients with symptomatic hallux valgus in the short and medium term. Pulse-dose radiofrequency may improve pain control and quality of life in patients with hallux valgus refractory to conservative therapies. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  6. Progressive valgus angulation of the ankle secondary to loss of fibular congruity treated with medial tibial hemiepiphysiodesis and fibular reconstruction.

    PubMed

    Lesiak, Alex C; Esposito, Paul W

    2014-06-01

    The fibula is an important stabilizer of the lateral ankle. Discontinuity of the fibular shaft can lead to progressive pain and shortening of the fibula, ultimately causing loss of lateral support to the ankle. Two children, who sustained segmental bone loss of the shaft of the fibula, developed progressive symptomatic valgus of the ankle with widening of the mortice and lateral subluxation of the talus. Both patients were treated with fibular plating and grafting with tricalcium sulfate with acute reconstitution of fibular length. Distal medial tibial hemiepiphysiodesis was simultaneously performed. One patient required revision plating and grafting 14 months after the index surgery because of plate failure. The valgus angulation and the widened medial mortice were corrected in the ankles of both patients, who returned to full activities. The patients were followed to maturity; the correction has been maintained, and they remain asymptomatic. The technique used in these cases can correct valgus angulation secondary to loss of fibular congruity rather than only halting progression of the deformity.

  7. Distal Femoral Osteotomy for the Valgus Knee: Medial Closing Wedge Versus Lateral Opening Wedge: A Systematic Review.

    PubMed

    Wylie, James D; Jones, Daniel L; Hartley, Melissa K; Kapron, Ashley L; Krych, Aaron J; Aoki, Stephen K; Maak, Travis G

    2016-10-01

    (1) To determine the radiographic correction/healing rate, patient-reported outcomes, reoperation rate, and complication rate after distal femoral osteotomy (DFO) for the valgus knee with lateral compartment pathology. (2) To summarize the reported results of medial closing wedge and lateral opening wedge DFO. We conducted a systematic review of PubMed, MEDLINE, and CINAHL to identify studies reporting outcomes of DFOs for the valgus knee. Keywords included "distal femoral osteotomy," "chondral," "cartilage," "valgus," "joint restoration," "joint preservation," "arthritis," and "gonarthrosis." Two authors first reviewed the articles; our study exclusion criteria were then applied, and the articles were included on the basis relevance defined by the aforementioned criteria. The Methodological Index for Nonrandomized Studies scale judged the quality of the literature. Sixteen studies were relevant to the research questions out of 191 studies identified by the original search. Sixteen studies were identified reporting on 372 osteotomies with mean follow-up of 45 to 180 months. All studies reported mean radiographic correction to a near neutral mechanical axis, with 3.2% nonunion and 3.8% delayed union rates. There was a 9% complication rate and a 34% reoperation rate, of which 15% were converted to arthroplasty. There were similar results reported for medial closing wedge and lateral opening wedge techniques, with a higher conversion to arthroplasty in the medial closing wedge that was confounded by longer mean follow-up in this group (mean follow-up 100 v 58 months). DFOs for the valgus knee with lateral compartment disease provide improvements in patient-reported knee health-related quality of life at midterm follow-up but have high rates of reoperation. No evidence exists proving better results of either the lateral opening wedge or medial closing wedge techniques. Level IV, systematic review of Level IV studies. Copyright © 2016 Arthroscopy Association of North

  8. Association of knee confidence with pain, knee instability, muscle strength, and dynamic varus-valgus joint motion in knee osteoarthritis.

    PubMed

    Skou, Søren T; Wrigley, Tim V; Metcalf, Ben R; Hinman, Rana S; Bennell, Kim L

    2014-05-01

    To investigate associations between self-reported knee confidence and pain, self-reported knee instability, muscle strength, and dynamic varus-valgus joint motion during walking. We performed a cross-sectional analysis of baseline data from 100 participants with symptomatic and radiographic medial tibiofemoral compartment osteoarthritis (OA) and varus malalignment recruited for a randomized controlled trial. The extent of knee confidence, assessed using a 5-point Likert scale item from the Knee Injury and Osteoarthritis Outcome Score, was set as the dependent variable in univariable and multivariable ordinal regression, with pain during walking, self-reported knee instability, quadriceps strength, and dynamic varus-valgus joint motion during walking as independent variables. One percent of the participants were not troubled with lack of knee confidence, 17% were mildly troubled, 50% were moderately troubled, 26% were severely troubled, and 6% were extremely troubled. Significant associations were found between worse knee confidence and higher pain intensity, worse self-reported knee instability, lower quadriceps strength, and greater dynamic varus-valgus joint motion. The multivariable model consisting of the same variables significantly accounted for 24% of the variance in knee confidence (P < 0.001). Worse knee confidence is associated with higher pain, worse self-reported knee instability, lower quadriceps muscle strength, and greater dynamic varus-valgus joint motion during walking. Since previous research has shown that worse knee confidence is predictive of functional decline in knee OA, addressing lack of knee confidence by treating these modifiable impairments could represent a new therapeutic target. Copyright © 2014 by the American College of Rheumatology.

  9. Results of total knee replacement with a cruciate-retaining model for severe valgus deformity--a study of 48 patients followed for an average of 9 years.

    PubMed

    Koskinen, Esa; Remes, Ville; Paavolainen, Pekka; Harilainen, Arsi; Sandelin, Jerker; Tallroth, Kaj; Kettunen, Jyrki; Ylinen, Pekka

    2011-06-01

    The objectives of the present study were to find out the results and the factors affecting survival after primary knee arthroplasty with a cruciate-retaining prosthesis in severe valgus deformity. Forty-eight patients (52 knees) participated in the current follow-up study. All patients were followed at least 5 years or to first revision. Mean follow-up time was 9 years (range, 1 to 17 years).The Kaplan-Meier analysis revealed 79% (95% CI 68% to 91%) survival rate with revision for any reason and 81% (95% CI 70% to 93%) survival rate with revision for instability as an endpoint at 10 years. Preoperatively TFA was 23° (range, 15°-51°) in valgus and 7° (range, 21° valgus-4° varus) in valgus postoperatively. Of the 14 re-operated patients, eight were revised because of progressive postoperative medial collateral ligament instability. All re-operations were performed during the first 4 years of the follow-up. The mean TFA was 15.5° valgus postoperatively for those eight and the odds ratio for a revision was 2 (95% CI 1-3, p = 0.025) when compared to the rest of the study population. The residual valgus deformity increases the risk of re-operation and it should be avoided. If proper soft-tissue balance cannot be achieved or there is no functional medial collateral ligament present more constrained implants should be used. In selected cases where both bony correction and ligament balancing have properly been achieved the use of a cruciate-retaining type of prosthesis is justified. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. [Hindfoot valgus. Diagnosis and therapy of flatfoot].

    PubMed

    Radl, R; Fuhrmann, G; Maafe, M; Krifter, R-M

    2012-04-01

    The clinical finding of flatfoot is characterized by a flattening of the medial longitudinal arch and valgus deformity of the hindfoot. The differential diagnosis of flatfoot is the physiological, flexible, contracted flatfoot, which occurs as a congenital or acquired deformity. Congenital flatfoot deformity requires early intensive therapy, while a flexible flatfoot in children has a good prognosis and conservative treatment usually leads to a stable and sufficient load-bearing foot. Severe flatfoot in children can be corrected successfully by simple, minimally invasive procedures. In adults with symptomatic flatfoot, which usually occurs due to an insufficiency of the tendon of the tibialis posterior, conservative therapy with insoles, shoe modifications and physiotherapeutic measures can lead to significant improvement, otherwise surgical correction is recommended. Early, stage-appropriate therapy helps to prevent an impending decompensation of the hindfoot.

  11. Comparison of calcaneal fixation of a retrograde intramedullary nail with a fixed-angle spiral blade versus a fixed-angle screw.

    PubMed

    Klos, Kajetan; Gueorguiev, Boyko; Schwieger, Karsten; Fröber, Rosemarie; Brodt, Steffen; Hofmann, Gunther O; Windolf, Markus; Mückley, Thomas

    2009-12-01

    Retrograde intramedullary nailing is an established technique for tibiotalocalcaneal arthrodesis (TTCA). In poor bone stock (osteoporosis, neuroarthropathy), device fixation in the hindfoot remains a problem. Fixed-angle spiral-blade fixation of the nail in the calcaneus could be useful. In seven matched pairs of human below-knee specimens, bone mineral density (BMD) was determined, and TTCA was performed with an intramedullary nail (Synthes Hindfoot Arthrodesis Nail HAN Expert Nailing System), using a conventional screw plus a fixed-angle spiral blade versus a conventional screw plus a fixed-angle screw, in the calcaneus. The constructs were subjected to quasi-static loading (dorsiflexion/plantarflexion, varus/valgus, rotation) and to cyclic loading to failure. Parameters studied were construct neutral zone (NZ) and range of motion (ROM), and number of cycles to failure. With dorsiflexion/plantarflexion loading, the screw-plus-spiral-blade constructs had a significantly smaller ROM in the quasi-static test (p = 0.028) and early in the cyclic test (p = 0.02); differences in the other parameters were not significant. There was a significant correlation between BMD and cycles to failure for the two-screw constructs (r = 0.94; p = 0.002) and for the screw-plus-spiral-blade constructs (r = 0.86; p = 0.014). In TTCA with a HAN Expert Nailing System, the use of a calcaneal spiral blade can further reduce motion within the construct. This may be especially useful in poor bone stock. Results obtained in this study could be used to guide the operating surgeon's TTCA strategy.

  12. Rehabilitation after hallux valgus surgery: importance of physical therapy to restore weight bearing of the first ray during the stance phase.

    PubMed

    Schuh, Reinhard; Hofstaetter, Stefan G; Adams, Samuel B; Pichler, Florian; Kristen, Karl-Heinz; Trnka, Hans-Joerg

    2009-09-01

    Operative treatment of people with hallux valgus can yield favorable clinical and radiographic results. However, plantar pressure analysis has demonstrated that physiologic gait patterns are not restored after hallux valgus surgery. The purpose of this study was to illustrate the changes of plantar pressure distribution during the stance phase of gait in patients who underwent hallux valgus surgery and received a multimodal rehabilitation program. This was a prospective descriptive study. Thirty patients who underwent Austin (n=20) and scarf (n=10) osteotomy for correction of mild to moderate hallux valgus deformity were included in this study. Four weeks postoperatively they received a multimodal rehabilitation program once per week for 4 to 6 weeks. Plantar pressure analysis was performed preoperatively and 4 weeks, 8 weeks, and 6 months postoperatively. In addition, range of motion of the first metatarsophalangeal joint was measured, and the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot questionnaire was administered preoperatively and at 6 months after surgery. The mean AOFAS score significantly increased from 60.7 points (SD=11.9) preoperatively to 94.5 points (SD=4.5) 6 months after surgery. First metatarsophalangeal joint range of motion increased at 6 months postoperatively, with a significant increase in isolated dorsiflexion. In the first metatarsal head region, maximum force increased from 117.8 N to 126.4 N and the force-time integral increased from 37.9 N.s to 55.6 N.s between the preoperative and 6-month assessments. In the great toe region, maximum force increased from 66.1 N to 87.2 N and the force-time integral increased from 18.7 N.s to 24.2 N.s between the preoperative and 6-month assessments. A limitation of the study was the absence of a control group due to the descriptive nature of the study. The results suggest that postoperative physical therapy and gait training may lead to improved function and weight bearing of the first

  13. Risk factors of avascular necrosis of the femoral head and fixation failure in patients with valgus angulated femoral neck fractures over the age of 50 years.

    PubMed

    Song, Hyung Keun; Choi, Ho June; Yang, Kyu Hyun

    2016-12-01

    The aim of our study was to identify the risk factors for avascular necrosis of the femoral head (AVN) and fixation failure (FF) after screw osteosynthesis in patients with valgus angulated femoral neck fractures. We conducted a retrospective study of 308 patients (mean age, 72.5 years, range, 50-97 years), with a mean follow-up of 21.4 months (range, 12-64 months). The risk for failure in treatment (FIT) associated with patient- and fracture-related factors was evaluated by logistic regression analyses. FIT was identified in 32 cases (10.3%): 22 cases (7.1%) of AVN and 10 cases (3.2%) of FF. Initial valgus tilt>15° (p=0.023), posterior tilt>15° (p=0.012), and screw sliding distance (p=0.037) were significantly associated with FIT. FIT occurred in 7 patients (5.2%) with B1.2.1 fractures and 17 patients (48.6%) with B1.1.2 fractures (p<0.001). The odds of FIT were 17-fold higher in patients with initial valgus and posterior tilts>15° (B1.1.2) compared to patients with <15° of tilt in both planes (B1.2.1). The severity of initial deformity predicts AVN and FF in patients with valgus angulated femoral neck fractures. Patients with an initial valgus and posterior tilt>15° are reasonable candidates for primary arthroplasty due to high risk of FIT. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. The percutaneous pie-crusting medial release during arthroscopic procedures of the medial meniscus does neither affect valgus laxity nor clinical outcome.

    PubMed

    Jeon, Sang-Woo; Jung, Min; Chun, Yong-Min; Lee, Su-Keon; Jung, Woo Seok; Choi, Chong Hyuk; Kim, Sung-Jae; Kim, Sung-Hwan

    2017-12-28

    To analyze the effect of percutaneous pie-crusting medial release on valgus laxity before and after surgery and on clinical outcomes. Eight-hundred fourteen consecutive patients who underwent an arthroscopic procedure for the medial compartment of the knee were evaluated retrospectively. Sex, age, type of operation (meniscectomy, meniscal repair, and posterior root repair), type of accompanying surgery (none, cartilage procedure, ligament procedure and osteotomy) were documented. Sixty-four patients who underwent percutaneous pie-crusting medial release (release group) and 64 who did not undergo medial release (non-release group) were matched using the propensity score method. Each patient was evaluated for the following variables: degree of valgus laxity on stress radiographs, Lysholm knee score, visual analog scale score, and International Knee Documentation Committee knee score and grade. At the 24-month follow-up, no significant increase in side-to-side differences in the valgus gap was observed in comparison to the preoperative value in the release group [preoperative, - 0.1 ± 1.3 mm; follow-up, - 0.1 ± 1.4 mm; (n.s.)]. The follow-up Lysholm score, visual analog scale score and International Knee Documentation Committee knee score and grade were similar between the two groups. Percutaneous pie-crusting medial release is an additional procedure that can be performed during arthroscopic surgery for patients with a narrow medial joint space of the knee. Percutaneous pie-crusting medial release reduces iatrogenic injury to the cartilage and does not produce any residual valgus laxity of the knee. IV.

  15. Effect of medial arch support foot orthosis on plantar pressure distribution in females with mild-to-moderate hallux valgus after one month of follow-up.

    PubMed

    Farzadi, Maede; Safaeepour, Zahra; Mousavi, Mohammad E; Saeedi, Hassan

    2015-04-01

    Higher plantar pressures at the medial forefoot are reported in hallux valgus. Foot orthoses with medial arch support are considered as an intervention in this pathology. However, little is known about the effect of foot orthoses on plantar pressure distribution in hallux valgus. To investigate the effect of a foot orthosis with medial arch support on pressure distribution in females with mild-to-moderate hallux valgus. Quasi-experimental. Sixteen female volunteers with mild-to-moderate hallux valgus participated in this study and used a medial arch support foot orthosis for 4 weeks. Plantar pressure for each participant was assessed using the Pedar-X(®) in-shoe system in four conditions including shoe-only and foot orthosis before and after the intervention. The use of the foot orthosis for 1 month led to a decrease in peak pressure and maximum force under the hallux, first metatarsal, and metatarsals 3-5 (p < 0.05). In the medial midfoot region, peak pressure, maximum force, and contact area were significantly higher with the foot orthosis than shoe-only before and after the intervention (p = 0.00). A foot orthosis with medial arch support could reduce pressure beneath the hallux and the first metatarsal head by transferring the load to the other regions. It would appear that this type of foot orthosis can be an effective method of intervention in this pathology. Findings of this study will improve the clinical knowledge about the effect of the medial arch support foot orthosis used on plantar pressure distribution in hallux valgus pathology. © The International Society for Prosthetics and Orthotics 2014.

  16. Varus and valgus stress tests after total knee arthroplasty with and without anesthesia.

    PubMed

    Tsukeoka, Tadashi; Tsuneizumi, Yoshikazu

    2016-03-01

    Retrospective studies demonstrated inadequate soft tissue balance is associated with the long-term outcome of total knee arthroplasty (TKA). However, most of these studies have evaluated the joint laxity only postoperatively without anesthesia. Therefore information about the effect of anesthesia on knee laxity is important for soft tissue balancing at the time of surgery. This study was conducted to determine how anesthesia affects the varus and valgus stress tests after TKA. A consecutive series of 26 patients undergoing staged bilateral TKA was evaluated. Varus and valgus laxity of the knee with the TKA implant was measured a few days before the contralateral TKA without anesthesia and again immediately after the contralateral TKA under spinal anesthesia. The laxity was significantly increased from 3.0° to 3.6° (p = 0.005) and from 4.7° to 5.7° (p = 0.007) in medial and lateral side, respectively, when the stress tests were performed under anesthesia in comparison to the laxity measured without anesthesia. The major change in laxity (≥3°) was measured in 6 (23%) patients tested without anesthesia. Anesthesia significantly influenced knee joint laxity after TKA. The findings of this study suggest that muscular forces impart a stabilizing force across the joint.

  17. Postoperative Knee Flexion Angle Is Affected by Lateral Laxity in Cruciate-Retaining Total Knee Arthroplasty.

    PubMed

    Nakano, Naoki; Matsumoto, Tomoyuki; Muratsu, Hirotsugu; Takayama, Koji; Kuroda, Ryosuke; Kurosaka, Masahiro

    2016-02-01

    Although many studies have reported that postoperative knee flexion is influenced by preoperative conditions, the factors which affect postoperative knee flexion have not been fully elucidated. We tried to investigate the influence of intraoperative soft tissue balance on postoperative knee flexion angle after cruciate-retaining (CR) total knee arthroplasty (TKA) using a navigation and an offset-type tensor. We retrospectively analyzed 55 patients with osteoarthritis who underwent TKA using e.motion-CR (B. Braun Aesculap, Germany) whose knee flexion angle could be measured at 2 years after operation. The exclusion criteria included valgus deformity, severe bony defect, infection, and bilateral TKA. Intraoperative varus ligament balance and joint component gap were measured with the navigation (Orthopilot 4.2; B. Braun Aesculap) while applying 40-lb joint distraction force at 0° to 120° of knee flexion using an offset-type tensor. Correlations between the soft tissue parameters and postoperative knee flexion angle were analyzed using simple linear regression models. Varus ligament balance at 90° of flexion (R = 0.56; P < .001) and lateral compartment gap at 90° of flexion (R = 0.51; P < .001) were positively correlated with postoperative knee flexion angle. In addition, as with past studies, joint component gap at 90° of flexion (R = 0.30; P < .05) and preoperative knee flexion angle (R = 0.63; P < .001) were correlated with postoperative knee flexion angle. Lateral laxity as well as joint component gap at 90° of flexion is one of the most important factors affecting postoperative knee flexion angle in CR-TKA. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Relationships between age at menarche, walking gait base of support, and stance phase frontal plane knee biomechanics in adolescent females

    PubMed Central

    Grannis, Kimberly A.; Sherwood, Richard J.; Duren, Dana L

    2016-01-01

    Background Age at menarche impacts patterns of pubertal growth and skeletal development. These effects may carry over into variation in biomechanical profiles involved in sports-related traumatic and overuse knee injuries. The present study investigated whether age at menarche is a potential indicator of knee injury risk through its influence on knee biomechanics during normal walking. Objective To test the hypothesis that earlier menarche is related to post-pubertal biomechanical risk factors for knee injuries, including a wider, more immature gait base of support, and greater valgus knee angles and moments. Design Cross-sectional observational study. Setting University research facility. Participants Healthy, post-menarcheal, adolescent females. Methods Age at menarche was obtained by recall questionnaire. Pubertal growth and anthropometric data were collected using standard methods. Biomechanical data were taken from tests of walking gait at self-selected speed. Reflective marker position data were collected using a three-dimensional quantitative motion analysis system, and three force plates recorded kinetic data. Main Outcome Measures Age at menarche; growth and anthropometric measurements; base of support; static knee frontal plane angle; dynamic knee frontal plane angles and moments during stance. Results Earlier menarche was significantly correlated with abbreviated pubertal growth and post-pubertal retention of immature traits, including a wider base of support. Earlier menarche and wider base of support were both correlated with more valgus static knee angles, more valgus knee abduction angles and moments at foot-strike, and a more valgus peak knee abduction angle during stance. Peak knee abduction moment during stance was not correlated with age at menarche or base of support. Conclusions Earlier menarche and its effects on growth are associated with retention of a relatively immature gait base of support and a tendency for static and dynamic valgus knee

  19. Postoperative pain and preemptive local anesthetic infiltration in hallux valgus surgery.

    PubMed

    Gądek, Artur; Liszka, Henryk; Wordliczek, Jerzy

    2015-03-01

    Several techniques of anesthesia are used in foot surgery. Preemptive analgesia helps to prevent the development of hypersensitivity in the perioperative period. The aim of our study was to assess the role of preemptive local anesthetic infiltration and postoperative pain after hallux valgus surgery. We evaluated 118 patients who underwent modified chevron and mini-invasive Mitchell-Kramer bunionectomy of the first distal metatarsal. After spinal anesthesia each patient randomly received an infiltration of local anesthetic or the same amount of normal saline 10 minutes before the skin incision. We measured the intensity of pain 4, 8, 12, 16, 24, and 72 hours after the release of the tourniquet using a visual analogue scale (VAS). Rescue analgesia and all other side effects were noted. Preemptive analgesia resulted in less pain during the first 24 hours after surgery. The decrease of VAS score was significantly lower in the study group during all the short postoperative periods measured. The rescue analgesia was administered in 11.9% of patients in the injected group and 42.4% in the placebo group (P < .05). In the injected group we did not observe significant difference in VAS score between patients post-chevron and miniinvasive Mitchell-Kramer osteotomy of the first distal metatarsal. No systemic adverse effects were noted. One persistent injury of dorsomedial cutaneous nerve was observed. Preemptive local anesthetic infiltration was an efficient and safe method to reduce postoperative pain after hallux valgus surgery. The analgesic effect was satisfactory in both traditional and minimally invasive techniques. © The Author(s) 2014.

  20. Increases in tibial force imbalance but not changes in tibiofemoral laxities are caused by varus-valgus malalignment of the femoral component in kinematically aligned TKA.

    PubMed

    Riley, Jeremy; Roth, Joshua D; Howell, Stephen M; Hull, Maury L

    2018-01-29

    The purposes of this study were to quantify the increase in tibial force imbalance (i.e. magnitude of difference between medial and lateral tibial forces) and changes in laxities caused by 2° and 4° of varus-valgus (V-V) malalignment of the femoral component in kinematically aligned total knee arthroplasty (TKA) and use the results to detemine sensitivities to errors in making the distal femoral resections. Because V-V malalignment would introduce the greatest changes in the alignment of the articular surfaces at 0° flexion, the hypotheses were that the greatest increases in tibial force imbalance would occur at 0° flexion, that primarily V-V laxity would significantly change at this flexion angle, and that the tibial force imbalance would increase and laxities would change in proportion to the degree of V-V malalignment. Kinematically aligned TKA was performed on ten human cadaveric knee specimens using disposable manual instruments without soft tissue release. One 3D-printed reference femoral component, with unmodified geometry, was aligned to restore the native distal and posterior femoral joint lines. Four 3D-printed femoral components, with modified geometry, introduced V-V malalignments of 2° and 4° from the reference component. Medial and lateral tibial forces were measured during passive knee flexion-extension between 0° to 120° using a custom tibial force sensor. Eight laxities were measured from 0° to 120° flexion using a six degree-of-freedom load application system. With the tibial component kinematically aligned, the increase in the tibial force imbalance from that of the reference component at 0° of flexion was sensitive to the degree of V-V malalignment of the femoral component. Sensitivities were 54 N/deg (medial tibial force increasing > lateral tibial force) (p < 0.0024) and 44 N/deg (lateral tibial force increasing > medial tibial force) (p < 0.0077) for varus and valgus malalignments, respectively. Varus-valgus

  1. In vivo determination of the direction of rotation and moment-angle relationship of individual elbow muscles.

    PubMed

    Zhang, L; Butler, J; Nishida, T; Nuber, G; Huang, H; Rymer, W Z

    1998-10-01

    The direction of rotation (DOR) of individual elbow muscles, defined as the direction in which a muscle rotates the forearm relative to the upper arm in three-dimensional space, was studied in vivo as a function of elbow flexion and forearm rotation. Electrical stimulation was used to activate an individual muscle selectively, and the resultant flexion-extension, supination-pronation, and varus-valgus moments were used to determine the DOR. Furthermore, multi-axis moment-angle relationships of individual muscles were determined by stimulating the muscle at a constant submaximal level across different joint positions, which was assumed to result in a constant level of muscle activation. The muscles generate significant moments about axes other than flexion-extension, which is potentially important for actively controlling joint movement and maintaining stability about all axes. Both the muscle DOR and the multi axis moments vary with the joint position systematically. Variations of the DOR and moment-angle relationship across muscle twitches of different amplitudes in a subject were small, while there were considerable variations between subjects.

  2. Postoperative alignment of TKA in patients with severe preoperative varus or valgus deformity: is there a difference between surgical techniques?

    PubMed

    Rahm, Stefan; Camenzind, Roland S; Hingsammer, Andreas; Lenz, Christopher; Bauer, David E; Farshad, Mazda; Fucentese, Sandro F

    2017-06-21

    There have been conflicting studies published regarding the ability of various total knee arthroplasty (TKA) techniques to correct preoperative deformity. The purpose of this study was to compare the postoperative radiographic alignment in patients with severe preoperative coronal deformity (≥10° varus/valgus) who underwent three different TKA techniques; manual instrumentation (MAN), computer navigated instrumentation (NAV) and patient specific instrumentation (PSI). Patients, who received a TKA with a preoperative coronal deformity of ≥10° with available radiographs were included in this retrospective study. The groups were: MAN; n = 54, NAV; n = 52 and PSI; n = 53. The mechanical axis (varus / valgus) and the posterior tibial slope were measured and analysed using standing long leg- and lateral radiographs. The overall mean postoperative varus / valgus deformity was 2.8° (range, 0 to 9.9; SD 2.3) and 2.5° (range, 0 to 14.7; SD 2.3), respectively. The overall outliers (>3°) represented 30.2% (48 /159) of cases and were distributed as followed: MAN group: 31.5%, NAV group: 34.6%, PSI group: 24.4%. No significant statistical differences were found between these groups. The distribution of the severe outliers (>5°) was 14.8% in the MAN group, 23% in the NAV group and 5.6% in the PSI group. The PSI group had significantly (p = 0.0108) fewer severe outliers compared to the NAV group while all other pairs were not statistically significant. In severe varus / valgus deformity the three surgical techniques demonstrated similar postoperative radiographic alignment. However, in reducing severe outliers (> 5°) and in achieving the planned posterior tibial slope the PSI technique for TKA may be superior to computer navigation and the conventional technique. Further prospective studies are needed to determine which technique is the best regarding reducing outliers in patients with severe preoperative coronal deformity.

  3. Karl Ludloff (1864-1945): An Inventive Orthopedic Surgeon, His Work and His Surgical Technique for the Correction of Hallux Valgus.

    PubMed

    Markatos, Konstantinos; Karaoglanis, Georgios; Damaskos, Christos; Garmpis, Nikolaos; Tsourouflis, Gerasimos; Laios, Konstantinos; Tsoucalas, Gregory

    2018-05-01

    The purpose of this article is to summarize the work and pioneering achievements in the field of orthopedic surgery of the German orthopedic surgeon Karl Ludloff. Ludloff had an impact in the diagnostics, physical examination, orthopedic imaging, and orthopedic surgical technique of his era. He was a pioneer in the surgical treatment of dysplastic hip, anterior cruciate ligament reconstruction, and hallux valgus. His surgical technique for the correction of hallux valgus, initially stabilized with plaster of Paris, remained unpopular among other orthopedic surgeons for decades. In the 1990s, the advent and use of improved orthopedic materials for fixation attracted the interest of numerous orthopedic surgeons in the Ludloff osteotomy for its ability to correct the deformity in all 3 dimensions, its anatomic outcomes, and its low recurrence rate and patient satisfaction.

  4. Effect of Forefoot Strike on Lower Extremity Muscle Activity and Knee Joint Angle During Cutting in Female Team Handball Players.

    PubMed

    Yoshida, Naruto; Kunugi, Shun; Mashimo, Sonoko; Okuma, Yoshihiro; Masunari, Akihiko; Miyazaki, Shogo; Hisajima, Tatsuya; Miyakawa, Shumpei

    2015-06-01

    The purpose of this study is to examine the effects of different strike forms, during cutting, on knee joint angle and lower limb muscle activity. Surface electromyography was used to measure muscle activity in individuals performing cutting manoeuvres involving either rearfoot strikes (RFS) or forefoot strikes (FFS). Three-dimensional motion analysis was used to calculate changes in knee angles, during cutting, and to determine the relationship between muscle activity and knee joint angle. Force plates were synchronized with electromyography measurements to compare muscle activity immediately before and after foot strike. The valgus angle tends to be smaller during FFS cutting than during RFS cutting. Just prior to ground contact, biceps femoris, semitendinosus, and lateral head of the gastrocnemius muscle activities were significantly greater during FFS cutting than during RFS cutting; tibialis anterior muscle activity was greater during RFS cutting. Immediately after ground contact, biceps femoris and lateral head of the gastrocnemius muscle activities were significantly greater during FFS cutting than during RFS cutting; tibialis anterior muscle activity was significantly lower during FFS cutting. The results of the present study suggest that the hamstrings demonstrate greater activity, immediately after foot strike, during FFS cutting than during RFS cutting. Thus, FFS cutting may involve a lower risk of anterior cruciate ligament injury than does RFS cutting.

  5. The effect of tibiotalar alignment on coronal plane mechanics following total ankle replacement.

    PubMed

    Grier, A Jordan; Schmitt, Abigail C; Adams, Samuel B; Queen, Robin M

    2016-07-01

    Gait mechanics following total ankle replacement (TAR) have reported improved ankle motion following surgery. However, no studies have addressed the impact of preoperative radiographic tibiotalar alignment on post-TAR gait mechanics. We therefore investigated whether preoperative tibiotalar alignment (varus, valgus, or neutral) resulted in significantly different coronal plane mechanics or ground reaction forces post-TAR. We conducted a non-randomized study of 93 consecutive end-stage ankle arthritis patients. Standard weight-bearing radiographs were obtained preoperatively to categorize patients as having neutral (±4°), varus (≥5° of varus), or valgus (≥5° of valgus) coronal plane tibiotalar alignment. All patients underwent a standard walking assessment including three-dimensional lower extremity kinetics and kinematics preoperatively, 12 and 24 months postoperatively. A significant group by time interaction was observed for the propulsive vertical ground reaction force (vGRF), coronal plane hip range of motion (ROM) and the peak hip abduction moment. The valgus group demonstrated an increase in the peak knee adduction angle and knee adduction angle at heel strike when compared to the other groups. Coronal plane ankle ROM, knee and hip angles at heel strike, and the peak hip angle exhibited significant increases across time. Peak ankle inversion moment, peak knee abduction moment and the weight acceptance vGRF also exhibited significant increases across time. Neutral ankle alignment was achieved for all patients by 2 years following TAR. Restoration of neutral ankle alignment at the time of TAR in patients with preoperative varus or valgus tibiotalar alignment resulted in biomechanics similar to those of patients with neutral preoperative tibiotalar alignment by 24-month follow-up. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Relationships Between Age at Menarche, Walking Gait Base of Support, and Stance Phase Frontal Plane Knee Biomechanics in Adolescent Girls.

    PubMed

    Froehle, Andrew W; Grannis, Kimberly A; Sherwood, Richard J; Duren, Dana L

    2017-05-01

    Age at menarche impacts patterns of pubertal growth and skeletal development. These effects may carry over into variation in biomechanical profiles involved in sports-related traumatic and overuse knee injuries. The present study investigated whether age at menarche is a potential indicator of knee injury risk through its influence on knee biomechanics during normal walking. To test the hypothesis that earlier menarche is related to postpubertal biomechanical risk factors for knee injuries, including a wider, more immature gait base of support, and greater valgus knee angles and moments. Cross-sectional observational study. University research facility. Healthy, postmenarcheal, adolescent girls. Age at menarche was obtained by recall questionnaire. Pubertal growth and anthropometric data were collected by using standard methods. Biomechanical data were taken from tests of walking gait at self-selected speed. Reflective marker position data were collected with a 3-dimensional quantitative motion analysis system, and 3 force plates recorded kinetic data. Age at menarche; growth and anthropometric measurements; base of support; static knee frontal plane angle; and dynamic knee frontal plane angles and moments during stance. Earlier menarche was correlated significantly with abbreviated pubertal growth and postpubertal retention of immature traits, including a wider base of support. Earlier menarche and wider base of support were both correlated with more valgus static knee angles, more valgus knee abduction angles and moments at foot-strike, and a more valgus peak knee abduction angle during stance. Peak knee abduction moment during stance was not correlated with age at menarche or base of support. Earlier menarche and its effects on growth are associated with retention of a relatively immature gait base of support and a tendency for static and dynamic valgus knee alignment. This biomechanical profile may put girls with earlier menarche at greater risk for sports

  7. Characteristics of Selected Anthropometric Foot Indicators in Physically Active Students.

    PubMed

    Bac, Aneta; Bogacz, Gabriela; Ogrodzka-Ciechanowicz, Katarzyna; Kulis, Aleksandra; Szaporów, Tomasz; Woźniacka, Renata; Radlińska, Natalia

    2018-05-01

    The aim of this study was to determine the type of medial longitudinal arch (MLA) in students of Krakow universities, investigate the relationship between physical activity and the shaping of the feet, and examine the relationship between hallux valgus angle and the type of footwear chosen most often. The study group consisted of 120 students, of which 56 respondents were students of the University School of Physical Education in Krakow, whereas the remaining 64 respondents were students of the Pedagogical University of Krakow. To evaluate the MLA, a podoscope was used, which allowed us to determine the length and width of the foot, and calculation of the Clarke angle, heel angle γ, and the angle of hallux valgus. All students were also subjected to a measurement of body weight and height. There was a statistically significant relationship between physical activity and the Clarke angle in the group of women studying at the University School of Physical Education. There was no correlation between the hallux valgus angle and the type of footwear chosen most often in the research groups. The most frequently diagnosed type of longitudinal and transverse arch foot in the research group was normal MLA. There was no relationship between physical activity and transverse arch foot in any of the research groups.

  8. The Validity of a New Low-Dose Stereoradiography System to Perform 2D and 3D Knee Prosthetic Alignment Measurements.

    PubMed

    Meijer, Marrigje F; Velleman, Ton; Boerboom, Alexander L; Bulstra, Sjoerd K; Otten, Egbert; Stevens, Martin; Reininga, Inge H F

    2016-01-01

    The EOS stereoradiography system has shown to provide reliable varus/valgus (VV) measurements of the lower limb in 2D (VV2D) and 3D (VV3D) after total knee arthroplasty (TKA). Validity of these measurements has not been investigated yet, therefore the purpose of this study was to determine validity of EOS VV2D and VV3D. EOS images were made of a lower limb phantom containing a knee prosthesis, while varying VV angle from 15° varus to 15° valgus and flexion angle from 0° to 20°, and changing rotation from 20° internal to 20° external rotation. Differences between the actual VV position of the lower limb phantom and its position as measured on EOS 2D and 3D images were investigated. Rotation, flexion or VV angle alone had no major impact on VV2D or VV3D. Combination of VV angle and rotation with full extension did not show major differences in VV2D measurements either. Combination of flexion and rotation with a neutral VV angle showed variation of up to 7.4° for VV2D; maximum variation for VV3D was only 1.5°. A combination of the three variables showed an even greater distortion of VV2D, while VV3D stayed relatively constant. Maximum measurement difference between preset VV angle and VV2D was 9.8°, while the difference with VV3D was only 1.9°. The largest differences between the preset VV angle and VV2D were found when installing the leg in extreme angles, for example 15° valgus, 20° flexion and 20° internal rotation. After TKA, EOS VV3D were more valid than VV2D, indicating that 3D measurements compensate for malpositioning during acquisition. Caution is warranted when measuring VV angle on a conventional radiograph of a knee with a flexion contracture, varus or valgus angle and/or rotation of the knee joint during acquisition.

  9. The dowel technique for first metatarso-phalangeal joint arthrodesis in revision surgery with bone loss.

    PubMed

    Malagelada, Francesc; Welck, Matthew J; Clark, Callum

    2017-02-27

    The operative management of failed first metatarso-phalangeal joint (MTPJ) surgery is often complicated by bone loss and shortening of the hallux. Restoration of first ray length and alignment often cannot be achieved with in situ fusion and reconstruction techniques with bone graft are therefore required. We present a novel technique of longitudinal (proximo-distal) bone dowel arthrodesis for first MTPJ arthrodesis with bone loss. Between August 2007 and February 2015, eight patients have been treated by the senior author with this technique. The mean age at surgery was 60.5 years (range 45-80) with seven females and one male. Index surgery was MTPJ arthrodesis (three patients), Keller excision arthroplasty (two patients), MTPJ hemiarthroplasty (two patients) and silastic arthroplasty (one patient). Clinical and radiological fusion was assessed and other radiological measurements included hallux valgus angle (HVA) and length of the hallux (LOH). All patients achieved fusion at a mean of 9.3 weeks (range 6-12) from surgery and only one patient required removal of metalwork. There were no major complications. The HVA improved in all cases from 21.4±2.8 pre-operatively to 11.6±3.5 post-operatively (p>0.05). The LOH also increased in all cases from 82.1±8.3mm to 86.7±8.2mm (p>0.05). The subgroup of patients who were revised from an arthroplasty, where maintenance of length rather than increase in length was desirable (hemiarthroplasty, silastic) had significantly lower increase in LOH than those revised from a non-arthroplasty index surgery (arthrodesis, Keller) (p=0.029). The dowel technique is successful for first MTPJ arthrodesis revision surgery with optimal union rates and satisfactory radiographic and clinical outcomes. It is an effective and versatile option for managing bone loss and deformity of the hallux. Copyright © 2017 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  10. Hindfoot Valgus following Interlocking Nail Treatment for Tibial Diaphysis Fractures: Can the Fibula Be Neglected?

    PubMed Central

    Uzun, Metin; Kara, Adnan; Adaş, Müjdat; Karslioğlu, Bülent; Bülbül, Murat; Beksaç, Burak

    2014-01-01

    Purpose. We evaluated whether intramedullary nail fixation for tibial diaphysis fractures with concomitant fibula fractures (except at the distal one-third level) managed conservatively with an associated fibula fracture resulted in ankle deformity and assessed the impact of the ankle deformity on lower extremity function. Methods. Sixty middle one-third tibial shaft fractures with associated fibular fractures, except the distal one-third level, were included in this study. All tibial shaft fractures were anatomically reduced and fixed with interlocking intramedullary nails. Fibular fractures were managed conservatively. Hindfoot alignment was assessed clinically. Tibia and fibular lengths were compared to contralateral measurements using radiographs. Functional results were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Foot and Ankle Disability Index Score (FADI). Results. Anatomic union, defined as equal length in operative and contralateral tibias, was achieved in 60 fractures (100%). Fibular shortening was identified in 42 fractures (68%). Mean fibular shortening was 1.2 cm (range, 0.5–2 cm). Clinical exams showed increased hindfoot valgus in 42 fractures (68%). The mean KOOS was 88.4, and the mean FADI score was 90. Conclusion. Fibular fractures in the middle or proximal one-third may need to be stabilized at the time of tibial intramedullary nail fixation to prevent development of hindfoot valgus due to fibular shortening. PMID:25544899

  11. Surgical Treatment of Moderate Hallux Valgus: A Comparison of Distal Chevron Metatarsal Osteotomy With and Without Lateral Soft-Tissue Release.

    PubMed

    Grle, Maki; Vrgoc, Goran; Bohacek, Ivan; Hohnjec, Vladimir; Martinac, Marko; Brkic, Iva; Stefan, Lovro; Jotanovic, Zdravko

    2017-12-01

    The purpose of the study was to determine whether lateral soft-tissue release (LSTR) has a beneficial or detrimental effect on the outcome of distal Chevron first metatarsal osteotomy (DCMO) in the treatment of moderate hallux valgus (HV). We compared the effect of different surgical treatments in 2 groups of patients: group I (23 patients, 25 feet, average age of 55 [from 43 to 77] years) was subjected to DCMO only, whereas group II (18 patients, 23 feet, average age of 59 [from 52 to 70] years]) was subjected to DCMO with LSTR. The American Orthopaedic Foot and Ankle Society's Hallux Metatarsophalangeal-Interphalangeal scale survey was conducted postoperatively, followed by the brief survey on postoperative patient satisfaction. The patient follow-up period was from 18 to 24 months after surgical treatment, on average. After surgical intervention, both groups of patients presented with an improved HV angle, but there was no significant difference between the groups. However, group II showed significant improvements in medial sesamoid bone position and patient satisfaction scores as compared with group I. Our midterm follow-up of surgical treatments for moderate HV deformity suggests that both procedures provide good postoperative results. However, according to our results, DCMO with LSTR provides better results than procedures without LSTR. Therapeutic, Level III: Retrospective comparative study.

  12. [Utilization of a porous alumina ceramic spacer in tibial valgus open-wedge osteotomy: fifty cases at 16 months mean follow-up].

    PubMed

    Bové, J C

    2002-09-01

    The aim of this work was to study the behavior of an inert porous alumina ceramic spacer used with a plate fixation for open-wedge tibial valgus osteotomy in patients with osteoarthritis of the knee and genu varum. The population included 50 patients who underwent surgery between October 1994 and December 2000. There were 31 women and 19 men, mean age 55 years at surgery (26 right knees and 24 left knees). Patients were reviewed at 3 weeks, 6 weeks, 3 months, 6 months, and one year, then every 2 years. Clinical and radiological data were available for all patients. Mean follow-up was 16 months. Two patients were lost to follow-up at 5 and 6 months. The results of the open-wedge tibial osteotomy were in agreement with the usual outcome reported in the literature concerning pain relief, functional recovery, joint motion, angle correction, and good preservation of the clinical and radiological result. Three fracture lines were observed on the lateral tibial plateau but did not affect final outcome or angle correction. There was however one case with loss of correction due to fracture of the screws. Radiographically, at 6 months, there were 9 thin lucent lines around the spacer (24%) which did not affect final outcome. Bone healing was achieved at 3 months on the average in all cases except 2 (4%) where healing was achieved at 8 and 13 months. The porous alumine spacer is a reliable biocompatible and mechanically stable element helpful for achieving bone healing. Integration into bone tissue was radiographically satisfactory. There were no specific complications related to use of the spacer.

  13. Impact of podiatry resident experience level in hallux valgus surgery on postoperative outcomes.

    PubMed

    Fleischer, Adam E; Yorath, Martin C; Joseph, Robert M; Baron, Adam; Nordquist, Thomas; Moore, Braden J; Robinson, Richmond C O; Reilly, Charles H

    2014-06-15

    Despite modern advancements in transosseous fixation and operative technique, hallux valgus (i.e., bunion) surgery is still associated with a higher than usual amount of patient dissatisfaction and is generally recognized as a complex and nuanced procedure requiring precise osseous and capsulotendon balancing. It stands to reason then that familiarity and skill level of trainee surgeons might impact surgical outcomes in this surgery. The aim of this study was to determine whether podiatry resident experience level influences midterm outcomes in hallux valgus surgery (HVS). Consecutive adults who underwent isolated HVS via distal metatarsal osteotomy at a single US metropolitan teaching hospital from January 2004 to January 2009 were contacted and asked to complete a validated outcome measure of foot health (Manchester-Oxford Foot Questionnaire) regarding their operated foot. Resident experience level was quantified using the surgical logs for the primary resident of record at the time of each case. Associations were assessed using linear and logistic regression analyses. A total of 102 adult patients (n = 102 feet) agreed to participate with a mean age of 46.8 years (standard deviation 13.1, range 18-71) and average length of follow-up 6.2 y (standard deviation 1.4, range 3.6-8.6). Level of trainee experience was not associated with postoperative outcomes in either the univariate (odds ratio 0.99 [95% confidence interval, 0.98-1.01], P = 0.827) or multivariate analyses (odds ratio 1.00 [95% confidence interval, 0.97-1.02], P = 0.907). We conclude that podiatry resident level of experience in HVS does not contribute appreciably to postoperative clinical outcomes. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Effects of Corrective Taping on Balance and Gait in Patients With Hallux Valgus.

    PubMed

    Gur, Gozde; Ozkal, Ozden; Dilek, Burcu; Aksoy, Songul; Bek, Nilgun; Yakut, Yavuz

    2017-05-01

    Taping is an effective temporary therapy for improving hallux valgus (HV) in adults. Although HV has been demonstrated to impair postural balance, there is a lack of information about how corrective taping affects balance and gait patterns in adults with HV deformity. Eighteen middle-aged female patients (average age, 53.5 years) with HV were included. Corrective tape was applied to correct HV angulation. A series of balance and gait stability tests were performed before applying tape and 1 hour after the tape was applied with a Balance Master computerized posturography device. The study involved the following tests: modified clinical test of sensory interaction and balance (mCTSIB), unilateral stance (US), limit of stability (LoS), step up/over (SUO), and walk across (WA) tests. No significant difference was found between the no-tape and taped condition in the static balance mCTSIB and US tests ( P > .05). The taping intervention resulted in significant improvement in the dynamic balance measures for the LoS test's backward reaction time and left maximum excursion ( P < .05), a significantly higher impact index bilaterally in the SUO assessment ( P < .05), and an increase in step width mean and variability in the WA test ( P < .05). Taping for correcting HV angulation had negative acute effects on dynamic balance in the SUO and WA tests and positive effects in the LoS test. Corrective taping, although a form of conservative treatment for hallux valgus, has been insufficiently studied in terms of effects on balance. Our results show that taping, as an acute effect, may impair balance in middle-aged adults when walking or ascending and descending stairs.

  15. Influence of varus/valgus positioning of the Nanos® and Metha® short-stemmed prostheses on stress shielding of metaphyseal bone.

    PubMed

    Brinkmann, V; Radetzki, F; Gutteck, N; Delank, S; Zeh, A

    2017-03-01

    The aim of this study was to analyze bone remodeling around the Nanos® (Smith & Nephew) and Metha® (Aesculap AG) implants as a function of varus/valgus stem positioning. In 75 patients with diagnosed coxarthrosis, either Nanos® (n= 51) or Metha® (n= 24) prostheses were implanted. Digital assessment of plain radiographs immediately, 97 days, and 381 days after THA showed no clinically-relevant migration, angulation, or change in offset and center of rotation. The DEXA scans showed significant BMD changes in Gruen zones 1 (-12.8%), 2 (-3.3%), 6 (+6.4%), and 7(-7.8%)(t-test). The pre/postoperative CCD for the Nanos® was 129°/ 135° and for the Metha® 131°/ 127°. Linear regression analysis showed no prediction for BMD by postoperative CCD or stem type. In conclusion, there was no clinically-relevant influence on proximal femur BMD according to varus/valgus implantation of the Nanos® or Metha® prostheses.

  16. Change in First Metatarsal Length After Proximal and Distal Chevron Osteotomies for Hallux Valgus Deformity.

    PubMed

    Lee, Jun Young; Lee, Yeon Soo; Song, Kyoung Chul; Choi, Kwi Youn

    2015-01-01

    The present study assessed the changes in the length of the first metatarsal bone after performing proximal chevron metatarsal osteotomy (PCMO) or distal Chevron metatarsal osteotomy (DCMO) for patients with hallux valgus deformity. A total of 60 patients with moderate-to-severe hallux valgus deformity from July 2009 to July 2011 were randomly divided into the PCMO and DCMO groups, with 30 patients in each group. The distal soft tissue procedure was performed in the same method for both groups. Measurements were performed preoperatively, postoperatively, and at the last follow-up visit at 6.1 ± 0.8 months. The postoperative length change with respect to the preoperative length was 0.7 ± 2.5 mm and -0.7 ± 5.1 mm for the PCMO and DCMO groups, respectively, with a slight lengthening of the first metatarsal bone in the PCMO group and a shortening in the DCMO group (p < .01). The follow-up length change with respect to the preoperative length was -2.1 ± 3.0 mm and -4.4 ± 2.2 mm for the PCMO and DCMO groups, respectively, demonstrating a clear shortening of the first metatarsal length at the last follow-up point in the DCMO group (p < .01).When DCMO and the distal soft tissue procedure were performed, significant shortening was found at 6 months of follow-up. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  17. Revision ulnar collateral ligament reconstruction using a suspension button fixation technique.

    PubMed

    Lee, Gregory H; Limpisvasti, Orr; Park, Maxwell C; McGarry, Michelle H; Yocum, Lewis A; Lee, Thay Q

    2010-03-01

    Revision ulnar collateral ligament reconstruction remains a challenging problem. The objective of this study was to biomechanically evaluate an ulnar collateral ligament reconstruction technique using a suspension button fixation technique that can be used even in the case of ulnar cortical bone loss. An ulnar suspension fixation technique for ulnar collateral ligament reconstruction can restore elbow kinematics and demonstrate failure strength comparable to that of currently available techniques. Controlled laboratory study. Nine pairs of cadaveric elbows were dissected free of soft tissue and potted. After simulating ulnar cortical bone loss, ulnar collateral ligament reconstruction was performed in 1 elbow of each pair using palmaris longus autograft and a 30-mm RetroButton suspended from the far (lateralmost) ulnar cortex. A docking technique was used for humeral fixation of the graft. Elbow valgus angle was quantified using a Microscribe 3DLX digitizer at multiple elbow flexion angles. Valgus angle was measured with the ulnar collateral ligament intact, transected, and reconstructed. In addition, load-to-failure testing was performed in 1 elbow of each pair. Release of the ulnar collateral ligament caused a significant increase in valgus angle at each flexion angle tested (P < .002). Reconstructed elbows demonstrated no significant differences in valgus angle from the intact elbow at all flexion angles tested. Load-to-failure tests showed that reconstructed elbows had an ultimate torque (10.3 + or - 5.7 N x m) significantly less than intact elbows (26.4 + or - 10.6 N x m) (P = .001). Ulnar collateral ligament reconstruction using a suspension button fixation technique reliably restored elbow kinematics to the intact state. Load-to-failure testing demonstrated comparable fixation strength to several historic controls of primary reconstruction techniques despite the simulated ulnar cortical bone loss. Ulnar collateral ligament reconstruction using a suspension

  18. Proximal Opening Wedge Osteotomy Provides Satisfactory Midterm Results With a Low Complication Rate.

    PubMed

    Oravakangas, Rami; Leppilahti, Juhana; Laine, Vesa; Niinimäki, Tuukka

    2016-01-01

    Hallux valgus is one of the most common foot deformities. Proximal opening wedge osteotomy is used for the treatment of moderate and severe hallux valgus with metatarsus primus varus. However, hypermobility of the first tarsometatarsal joint can compromise the results of the operation, and a paucity of midterm results are available regarding proximal open wedge osteotomy surgery. The aim of the present study was to assess the midterm results of proximal open wedge osteotomy in a consecutive series of patients with severe hallux valgus. Thirty-one consecutive adult patients (35 feet) with severe hallux valgus underwent proximal open wedge osteotomy. Twenty patients (35.5%) and 23 feet (34.3%) were available for the final follow-up examination. The mean follow-up duration was 5.8 (range 4.6 to 7.0) years. The radiologic measurements and American Orthopaedic Foot and Ankle Society hallux-metatarsophalangeal-interphalangeal scores were recorded pre- and postoperatively, and subjective questionnaires were completed and foot scan analyses performed at the end of the follow-up period. The mean hallux valgus angle decreased from 38° to 23°, and the mean intermetatarsal angle correction decreased from 17° to 10°. The mean improvement in the American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal score increased from 52 to 84. Two feet (5.7%) required repeat surgery because of recurrent hallux valgus. No nonunions were identified. Proximal open wedge osteotomy provided satisfactory midterm results in the treatment of severe hallux valgus, with a low complication rate. The potential instability of the first tarsometatarsal joint does not seem to jeopardize the midterm results of the operation. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Effect of foot type on knee valgus, ground reaction force, and hip muscle activation in female soccer players.

    PubMed

    Rath, Meghan E; Stearne, David J; Walker, Cameron R; Cox, Jaime C

    2016-05-01

    The purpose of this study was to determine the degree to which subtalar joint pronation resulting from a supple planus foot affects knee alignment, hip muscle activation and ground reaction force attenuation in female athletes during a broad jump-to-cut maneuver. Twelve National Collegiate Athletic Association (NCAA) Division II female soccer players (age=19.4±1.4 years, height=1.64±0.05 m, mass=64.10±4.8 kg) were identified as having either supple planus (SP) or rigid feet (RF). Participants completed three broad jump-to-cut trials onto a force plate while EMG and motion data were collected. Muscle activation levels (percentage of maximal voluntary contraction [%MVC]) in the gluteus maximus, gluteus medius, biceps femoris, and rectus femoris were calculated, and peak vertical and medial shear force, rate of loading, and valgus angle were collected for each trial. Mann-Whitney U tests revealed no statistical significance between foot-type groups, however, effect size statistics revealed practical significance for between-group %MVC biceps femoris (d=1.107), %MVC gluteus maximus (d=1.069), and vertical ground reaction force (d=1.061). Athletes with a SP foot type may experience decreased hip muscle activation associated with increased vertical ground reaction force during a broad jump-to-cut maneuver. This might result in reduced dynamic stability and neuromuscular control during deceleration, potentially increasing the risk of non-contact ACL injury in female soccer players.

  20. Optimizing intramedullary entry location on the proximal humerus based on variations of neck-shaft angle.

    PubMed

    Jeong, Jinyoung; Jung, Hyun-Woo

    2015-09-01

    The purpose of this study was to define the relationship between the humeral neck-shaft angle (NSA) and variations in the ideal entry portal aligned with the long axis of the intramedullary canal of the proximal humerus. Three-dimensional images of 36 cadaveric humeri with various NSAs were reconstructed by a computerized surgical simulation program. The anteroposterior, mediolateral, and linear distances between a line from the center of the proximal medullary canal to the bicipital groove were measured. Differences among humeri with various NSAs were analyzed. The intramedullary axis line was located a mean of 9 ± 2 mm posteriorly and 11 ± 3 mm medially from the bicipital groove. The axis line was 9 ± 2 mm posterior and 11 ± 2 mm medial with a standard NSA. The axis line in humeri with a varus NSA was 8 ± 2 mm posteriorly and 9 ± 2 mm medially, whereas the axis line was 10 ± 3 mm posteriorly and 14 ± 3 mm medially with a valgus NSA. The differences in the mediolateral distances between the groups were significant (P < .00009). Care should be taken in choosing the entry portal position in humeri with various NSAs as the entry portal position differs according to the NSA. It is recommended that the location of the entry portal be moved toward the center of the humeral head to align with the centerline of the intramedullary canal in humeri with a valgus NSA in particular. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  1. Bilateral carpal valgus deformity in hand-reared cheetah cubs (Acinonyx jubatus).

    PubMed

    Bell, Katherine M; van Zyl, Malan; Ugarte, Claudia E; Hartman, Angela

    2011-01-01

    Four hand-reared cheetah cubs (Acinonyx jubatus) exhibited progressively severe bilateral valgus deformity of the carpi (CV) during the weaning period. Radiographs of the thoracic limbs suggested normal bone ossification, and serum chemistry was unremarkable. All affected cubs developed CV shortly after the onset of gastroenteritis, which was treated medically, and included use of a prescription diet. A sudden decrease in growth rate was associated with gastrointestinal disease. Before gastroenteritis and CV, affected cubs had higher growth rates than unaffected cubs, despite similar mean daily energy intake. Return to normal thoracic limb conformation was consequent to dietary manipulation (including a reduction in energy intake and vitamin and mineral supplementation), as well as decreased growth rates and recovery from gastroenteritis. The cause of the CV is likely to have been multi-factorial with potentially complex physiological interactions involved. © 2010 Wiley-Liss, Inc.

  2. A comparison of Chevron and Lindgren-Turan osteotomy techniques in hallux valgus surgery: a prospective randomized controlled study.

    PubMed

    Uygur, Esat; Özkan, Namık Kemal; Akan, Kaya; Çift, Hakan

    2016-01-01

    The aim of this prospective randomized controlled single-blind study was to compare the results of Chevron and Lindgren-Turan osteotomy techniques for treatment of moderate hallux valgus. A total of 66 female patients (34 in Chevron group, 32 Lindgren-Turan group) were recruited in this study and followed up for an average of 26.08 months. Operative procedures were performed by 2 surgeons, and patients were evaluated by an another researcher who was blinded to the surgical technique. The groups were compared for their radiological and clinical results. Both techniques was clinically and radiologically effective (p<0.01). However, no significant differences were found between the 2 groups regarding American Orthopaedic Foot and Ankle Society's clinical rating system, Painful Foot Evaluation scale of Maryland University scores, or radiologic evaluation (p>0.05). Compared to the Chevron group, the Lindgren-Turan group was found to have shorter surgical duration (p<0.05) and significantly more shortening at the first metatarsal (p<0.05). In moderate hallux valgus deformity, both the Chevron and Lindgren-Turan osteotomy techniques are clinically and radiologically safe, effective, and reliable alternatives. No superiority was detected in either technique. Although shortening at the first metatarsal in the Lindgren-Turan group was radiologically significant, the results were clinically tolerable.

  3. The superficial medial collateral ligament is the primary medial restraint to knee laxity after cruciate-retaining or posterior-stabilised total knee arthroplasty: effects of implant type and partial release.

    PubMed

    Athwal, Kiron K; Daou, Hadi El; Kittl, Christoph; Davies, Andrew J; Deehan, David J; Amis, Andrew A

    2016-08-01

    The aim of this study was to quantify the contributions of medial soft tissues to stability following cruciate-retaining (CR) or posterior-stabilised (PS) total knee arthroplasty (TKA). Using a robotic system, eight cadaveric knees were subjected to ±90-N anterior-posterior force, ±5-Nm internal-external and ±8-Nm varus-valgus torques at various flexion angles. The knees were tested intact and then with CR and PS implants, and successive cuts of the deep and superficial medial collateral ligaments (dMCL, sMCL) and posteromedial capsule (PMC) quantified the percentage contributions of each structure to restraining the applied loads. In implanted knees, the sMCL restrained valgus rotation (62 % across flexion angles), anterior-posterior drawer (24 and 10 %, respectively) and internal-external rotation (22 and 37 %). Changing from CR TKA to PS TKA increased the load on the sMCL when resisting valgus loads. The dMCL restrained 11 % of external and 13 % of valgus rotations, and the PMC was significant at low flexion angles. This work has shown that medial release in the varus knee should be minimised, as it may inadvertently result in a combined laxity pattern. There is increasing interest in preserving constitutional varus in TKA, and this work argues for preservation of the sMCL to afford the surgeon consistent restraint and maintain a balanced knee for the patient.

  4. Assessment of medial elbow laxity by gravity stress radiography: comparison of valgus stress radiography with gravity and a Telos stress device.

    PubMed

    Harada, Mikio; Takahara, Masatoshi; Maruyama, Masahiro; Nemoto, Tadanobu; Koseki, Kazuhiko; Kato, Yoshihiro

    2014-04-01

    Valgus instability was reported to be higher with the elbow in 60° of flexion, rather than in 30° of flexion, although there are no studies using valgus stress radiography by gravity (gravity radiography) with the elbow in 60° of flexion. Fifty-seven patients with medial elbow pain participated. For both elbows, valgus stress radiography by use of a Telos device (Telos radiography) and gravity radiography, with the elbow in 60° of flexion, were performed for the assessment of medial elbow laxity. In both radiographs, the medial elbow joint space (MJS) on the affected side was compared with that on the opposite side, and the increase in the MJS on the affected side was assessed. For the Telos radiographs, the mean MJS was 4.7 mm on the affected side and 4.0 mm on the opposite side, with the mean increase in the MJS on the affected side being 0.7 mm. For the gravity radiographs, the mean MJS was 5.0 mm on the affected side and 4.2 mm on the opposite side, with the mean increase in the MJS on the affected side being 0.8 mm. There were significant correlations between the Telos and gravity radiographs in the MJS on the affected side, the MJS on the opposite side, and the increase in the MJS on the affected side (respectively, P < .0001). There was also a high level of intraobserver and interobserver reliability for the assessment of the gravity radiographs. Gravity radiography is useful for assessment of medial elbow laxity, similar to Telos radiography. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  5. Immediate effect of valgus bracing on knee joint moments in meniscectomised patients: An exploratory study.

    PubMed

    Thorning, Maria; Thorlund, Jonas B; Roos, Ewa M; Wrigley, Tim V; Hall, Michelle

    2016-12-01

    Patients undergoing medial arthroscopic partial meniscectomy are at increased risk of developing and/or progressing knee osteoarthritis, with increased medial compartment load being a potential contributor. The aim of this study was to evaluate the immediate effect of a valgus unloader knee brace on knee joint moments in patients following medial arthroscopic partial meniscectomy. Within-participant design. Twenty-two patients (age 35-55 years) who had undergone medial arthroscopic partial meniscectomy within the previous 8-15 months completed three-dimensional analysis of gait, forward lunge and one-leg rise during two conditions: with and without a valgus unloader knee brace. Outcome measures included the peak and impulse of the knee adduction moment and the peak knee flexion moment. The peak knee flexion moment increased during brace condition for forward lunge (mean difference [95% CI]) 0.54 [0.27-0.82] (Nm/(BW×HT)%), p<0.001 and one-leg rise (mean difference 0.45 [95% CI 0.08-0.82] (Nm/(BW×HT)%), p=0.022). No other significant differences were found between conditions in any of the included tasks. A significant effect of the knee brace was detected in terms of an increase in peak knee flexion moment during the more demanding tasks such as forward lunge and one-leg rise. This increase implies enhanced stability of the knee provided by the brace, which may induce increased knee function and knee-related confidence during strenuous tasks. Future research is required to explore the structural implications. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  6. The effect of conformation on orthopaedic health and performance in a cohort of National Hunt racehorses: preliminary results.

    PubMed

    Weller, R; Pfau, T; Verheyen, K; May, S A; Wilson, A M

    2006-11-01

    There is a lack of scientific data and studies on the effect of conformation on performance or on orthopaedic health. To investigate the relationship between conformation, injury and performance in racehorses used for racing over fences. Over 2 years, 108 National Hunt racehorses were followed and their medical and performance data recorded. Conformation was measured in 3D with a computerised motion analysis system. Linear multiple regression models were used to evaluate the effect of conformation on measures of race performance and stepwise forward logistic regression models to assess the effect on risk of injury. An increase in intermandibular width, flexor angle of the shoulder joint and coxal angle (the angle between the ilium and ischium) was demonstrated to have a positive effect on performance. Performance decreased with increasing girth, length of the hind digit and valgus conformation of the metacarpophalangeal joint. The risk of suffering from superficial digital flexor tendon injury increased with increasing metacarpophalangeal joint angle and with carpus valgus conformation. The risk of pelvic fracture increased with valgus conformation of the tarsus and decreased with an increasing coxal angle. Valgus deformation was demonstrated to be detrimental to performance or increased risk of injury, perhaps resulting in higher loads on musculoskeletal structures. The coxal angle was the only parameter to have an effect on both risk of injury and performance. An alignment of the muscles with the axis of the pelvis may be beneficial for force transmission and decrease the bending moment of the muscles on the bones. The statistical power of this study is limited, however it provides preliminary data necessary for the planning of a larger scale study on the effect of conformation on performance and risk of injury. Studies of the effects of conformation on performance and risk of injury may aid in identifying individuals likely to perform well on the racecourse and

  7. Stabilization of chevron bunionectomy with a capsuloperiosteal flap.

    PubMed

    Guclu, Berk; Kaya, Alper; Akan, Burak; Koken, Murat; Kemal Us, Ali

    2011-04-01

    Distal chevron osteotomy (DCO) for mild to moderate hallux valgus deformity is inherently more stable than the other forms of distal metatarsal osteotomy, but complications such as loss of correction, infection, joint stiffness, delayed union, malunion and nonunion can occur. In this study, we evaluated the use of a capsuloperiosteal flap for stabilization of DCO in the treatment of hallux valgus. A retrospective study was conducted on 59 patients (88 feet) that underwent distal Chevron osteotomy stabilized only with a capsuloperiosteal flap for mild and moderate hallux valgus deformity with a mean followup of 11.3 years. Clinical evaluation was calculated using the hallux score of the American Orthopaedic Foot and Ankle Society (AOFAS). The score improved from a preoperative mean of 52 to a mean of 91.5 points at last followup. Average hallux valgus angle changed from 30.3 degrees preoperatively to 14.2 degrees postoperatively at the last followup. Intermetatarsal angle 1-2 changed from 13.6 degrees preoperatively to 10.2 degrees postoperatively. The correction proved to be consistent with only an average of 3.4-degree correction loss and 4.9-degree loss in the range of motion. Eighty-six feet (97.7%) were pain free. Discomfort with shoewear was absent in 84 feet (95.5%) postoperatively and 24 of 25 (96%) patients were satisfied cosmetically. Capsuloperiosteal flap stabilization of distal chevron osteotomy for mild-moderate hallux valgus yielded excellent clinical results at long-term followup.

  8. Combined Effects of Fatigue and Surface Instability on Jump Biomechanics in Elite Athletes.

    PubMed

    Prieske, Olaf; Demps, Marie; Lesinski, Melanie; Granacher, Urs

    2017-09-01

    The present study aimed to examine the effects of fatigue and surface instability on kinetic and kinematic jump performance measures. Ten female and 10 male elite volleyball players (18±2 years) performed repetitive vertical double-leg box jumps until failure. Pre and post fatigue, jump height/performance index, ground reaction force and knee flexion/valgus angles were assessed during drop and countermovement jumps on stable and unstable surfaces. Fatigue, surface condition, and sex resulted in significantly lower drop jump performance and ground reaction force (p≤0.031, 1.1≤d≤3.5). Additionally, drop jump knee flexion angles were significantly lower following fatigue (p=0.006, d=1.5). A significant fatigue×surface×sex interaction (p=0.020, d=1.2) revealed fatigue-related decrements in drop jump peak knee flexion angles under unstable conditions and in men only. Knee valgus angles were higher on unstable compared to stable surfaces during drop jumps and in females compared to males during drop and countermovement jumps (p≤0.054, 1.0≤d≤1.1). Significant surface×sex interactions during countermovement jumps (p=0.002, d=1.9) indicated that knee valgus angles at onset of ground contact were significantly lower on unstable compared to stable surfaces in males but higher in females. Our findings revealed that fatigue and surface instability resulted in sex-specific knee motion strategies during jumping in elite volleyball players. © Georg Thieme Verlag KG Stuttgart · New York.

  9. Wound healing complications in patients with and without systemic diseases following hallux valgus surgery.

    PubMed

    Kromuszczyńska, Justyna; Kołodziej, Łukasz; Jurewicz, Alina

    2018-01-01

    There are many defined risk factors for wound healing. Comorbidities and their treatment are identified to be one of them. The aim of this study is to verify whether there are significant differences in wound healing between patients with and without systemic diseases, who underwent hallux valgus correction with Scarf osteotomy. A total of 155 consecutive patients were included into this prospective study. All of the patients underwent Scarf osteotomy for hallux valgus correction. In 60,6% of patients comorbidities were present, most often hypertension (57 patients, 36,8%), hypothyroidism (19 patients 12,3%) and diabetes (7 patients, 4,5%) occurred. Most of the patients were women (96,1%). During the study complication rate was noted. Patients underwent follow-up: 1,2, 3, 6 and 12 weeks and 6 months after the surgery. Preoperatively and during the last visit treatment results were assessed with AOFAS HMI scale. Scar assessment was performed by independent observer with VAS followed by patient scar assessment with VSS. In 30 patients complications were noted (19,4%). Surgical site infection was found in 6 patients (3,9%). In 13 patients (8,4%) partial wound dehiscence occurred, in 5 of them (3,2%) additional skin closure (Steri-Strips) was applied. Treatment results assessed with AOFAS HMI scale were good and very good in both healthy and comorbidity group, and the results improved significantly after surgical procedure. Scar assessment with VAS was on the average 1,5 pts. Average result in VSS was 2 pts. Results in both scales were rated as very good. No statistically significant differences were found in both healthy and comorbidity group in scar assessment. Based on the results of the study authors believe there are no significant differences between patients with and without comorbidities in aspects like: complication rate, surgery result and scar assessment as long as foot surgery is concerned.

  10. Hallux Valgus Deformity and Treatment: A Three-Dimensional Approach: Modified Technique for Lapidus Procedure.

    PubMed

    Santrock, Robert D; Smith, Bret

    2018-06-01

    In a hallux valgus deformity, the problem is deviation of the hallux at the metatarsophalangeal joint and of the first metatarsal at the tarsometatarsal joint. Although anterior-posterior radiograph findings have been prioritized, deviation in the other planes can substantially change visible cues. The modified technique for Lapidus procedure procedure, uses all 3 planes to evaluate and correct the deformity, making radiographic measurements less useful. Using a triplane framework and focusing on the apex of the deformity, all bunions become the same modified technique for Lapidus procedure can be performed regardless of the degree of deformity, always includes triplane correction, and deformity size becomes irrelevant. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Differences in Neuromuscular Strategies Between Landing and Cutting Tasks in Female Basketball and Soccer Athletes

    PubMed Central

    Cowley, Hanni R; Ford, Kevin R; Myer, Gregory D; Kernozek, Thomas W; Hewett, Timothy E

    2006-01-01

    Context: High school female athletes are most likely to sustain a serious knee injury during soccer or basketball, 2 sports that often involve a rapid deceleration before a change of direction or while landing from a jump. Objective: To determine if female high school basketball and soccer players show neuromuscular differences during landing and cutting tasks and to examine neuromuscular differences between tasks and between dominant and nondominant sides. Design: A 3-way mixed factorial design investigating the effects of sport (basketball, soccer), task (jumping, cutting), and side (dominant, nondominant). Setting: Laboratory. Patients or Other Participants: Thirty high school female athletes who listed either basketball or soccer as their only sport of participation (basketball: n = 15, age = 15.1 ± 1.7 years, experience = 6.9 ± 2.2 years, height = 165.3 ± 7.9 cm, mass = 61.8 ± 9.3 kg; soccer: n = 15, age = 14.8 ± 0.8 years, experience = 8.8 ± 2.5 years, height = 161.8 ± 4.1 cm, mass = 54.6 ± 7.6 kg). Main Outcome Measure(s): Ground reaction forces, stance time, valgus angles, and valgus moments were assessed during (1) a drop vertical jump with an immediate maximal vertical jump and (2) an immediate side-step cut at a 45° angle. Results: Basketball athletes had greater ground reaction forces (P < .001) and decreased stance time (P < .001) during the drop vertical jump, whereas soccer players had greater ground reaction forces (P <.001) and decreased stance time (P < .001) during the cut. Subjects in both sports had greater valgus angles (initial contact and maximum, P = .02 and P = .012, respectively) during cutting than during the drop vertical jump. Greater valgus moments (P = .006) were noted on the dominant side during cutting. Conclusions: Our subjects demonstrated differences in ground reaction forces and stance times during 2 movements associated with noncontact anterior cruciate ligament injuries. Knee valgus moment and angle were

  12. Photogrammetry on the identification of postural asymmetries in cadets and pilots of the Brazilian air force academy.

    PubMed

    Figueiredo, Rodrigo V; Amaral, Artur C; Shimano, Antônio C

    2012-01-01

    To identify whether flight training activities cause postural changes in cadets and pilots of the Brazilian Air Force Academy (AFA). Eighty subjects were assessed through photographic images in anterior and right side views. Four groups of cadets (n=20 per group) divided according to the year since enlistment and a fifth group of fifteen pilots from the Air Demonstration Squadron (ADS) were included. Pictures were analyzed using the Postural Analysis Program (SAPO) and angles related to head vertical alignment (HVA), head horizontal alignment (HHA), acromion horizontal alignment (AHA) and anterior-superior iliac spine horizontal alignment (HAS) were plotted. We did not find statistical significant differences in the angles: HVA, HHA and AHA. However, a significant difference was found for the HAS angle with pilots having lower values than cadets, suggesting greater postural stability for this variable in pilots. The horizontal alignment of the anterior-superior iliac spine was the only measure that showed significant difference in the comparison between pilots and cadets. The remaining alignments were not different, possibility because of the strict criteria used for admission of cadets at the AFA and the efficiency of the physical training that is performed periodically.

  13. Lengthening of the shortened first metatarsal after Wilson's osteotomy for hallux valgus.

    PubMed

    Singh, D; Dudkiewicz, I

    2009-12-01

    Metatarsalgia is a recognised complication following iatrogenic shortening of the first metatarsal in the management of hallux valgus. The traditional surgical treatment is by shortening osteotomies of the lesser metatarsals. We describe the results of lengthening of iatrogenic first brachymetatarsia in 16 females. A Scarf-type osteotomy was used in the first four cases and a step-cut of equal thicknesses along the axis of the first metatarsal was performed in the others. The mean follow-up was 21 months (19 to 26). Relief of metatarsalgia was obtained in the six patients in whom 10 mm of lengthening had been achieved, compared to only 50% relief in those where less than 8 mm of lengthening had been gained. One-stage step-cut lengthening osteotomy of the first metatarsal may be preferable to shortening osteotomies of the lesser metatarsals in the treatment of metatarsalgia following surgical shortening of the first metatarsal.

  14. Do CAS measurements correlate with EOS 3D alignment measurements in primary TKA?

    PubMed

    Meijer, Marrigje F; Boerboom, Alexander L; Bulstra, Sjoerd K; Reininga, Inge H F; Stevens, Martin

    2017-09-01

    Objective of this study was to compare intraoperative computer-assisted surgery (CAS) alignment measurements during total knee arthroplasty (TKA) with pre- and postoperative coronal alignment measurements using EOS 3D reconstructions. In a prospective study, 56 TKAs using imageless CAS were performed and coronal alignment measurements were recorded twice: before bone cuts were made and after implantation of the prosthesis. Pre- and postoperative coronal alignment measurements were performed using EOS 3D reconstructions. Thanks to the EOS radiostereography system, measurement errors due to malpositioning and deformity during acquisition are eliminated. CAS measurements were compared with EOS 3D reconstructions. Varus/valgus angle (VV), mechanical lateral distal femoral angle (mLDFA) and mechanical medial proximal tibial angle (mMPTA) were measured. Significantly different VV angles were measured pre- and postoperatively with CAS compared to EOS. For preoperative measurements, mLDFA did not differ significantly, but a significantly larger mMPTA in valgus was measured with CAS. Results of this study indicate that differences in alignment measurements between CAS measurements and pre- and postoperative EOS 3D are due mainly to the difference between weight-bearing and non-weight-bearing position and potential errors in validity and reliability of the CAS system. EOS 3D measurements overestimate VV angle in lower limbs with substantial mechanical axis deviation. For lower limbs with minor mechanical axis deviation as well as for mMPTA measurements, CAS measures more valgus than EOS. Eventually the results of this study are of clinical relevance, since it raises concerns regarding the validity and reliability of CAS systems in TKA. IIb.

  15. Determination of homovanillic acid (HVA) in human plasma by HPLC with coulometric detection and a new SPE procedure.

    PubMed

    Saracino, M A; Mandrioli, R; Mercolini, L; Ferranti, A; Zaimovic, A; Leonardi, C; Raggi, M A

    2006-09-11

    A sensitive high-performance liquid chromatographic method has been developed for the determination of homovanillic acid (HVA), the main metabolite of dopamine, in human plasma. Analyses were carried out on a reversed-phase column (C8, 250 mm x 4.6 mm i.d., 5 microm) using a mobile phase composed of 10% methanol and 90% aqueous citrate buffer, containing octanesulfonic acid and EDTA at pH 4.8. Coulometric detection was used, setting the guard cell at +0.100 V, the first analytical cell at -0.200 V and the second analytical cell at +0.500 V. A careful solid-phase extraction procedure, based on strong anion exchange (SAX) cartridges (100 mg, 1 mL), was implemented for the pre-treatment of plasma samples. Extraction yield was satisfactory, being the mean value 98.0%. The calibration curve was linear over the concentration range of 0.2-25.0 ng mL(-1) of homovanillic acid. The limit of quantitation (LOQ) was 0.2 ng mL(-1) and the limit of detection (LOD) was 0.1 ng mL(-1). The method was successfully applied to plasma samples from former alcohol, cocaine and heroin addicts. Results were satisfactory in terms of precision and accuracy. Hence, the method is suitable for the determination of homovanillic acid in human plasma.

  16. Knee Control and Jump-Landing Technique in Young Basketball and Floorball Players.

    PubMed

    Leppänen, M; Pasanen, K; Kulmala, J-P; Kujala, U M; Krosshaug, T; Kannus, P; Perttunen, J; Vasankari, T; Parkkari, J

    2016-04-01

    Poor knee alignment is associated with increased loading of the joints, ligaments and tendons, and may increase the risk of injury. The study purpose was to compare differences in knee kinematics between basketball and floorball players during a vertical drop jump (VDJ) task. We wanted to investigate whether basketball players, whose sport includes frequent jump-landings, exhibited better knee control compared with floorball players, whose sport involves less jumping. Complete data was obtained from 173 basketball and 141 floorball players. Peak knee valgus and flexion angles during the VDJ were analyzed by 3D motion analysis.Larger knee valgus angles were observed among basketball players (- 3.2°, 95%CI -4.5 to - 2.0) compared with floorball players (- 0.9°, 95%CI -2.3 to 0.6) (P=0.022). Basketball players landed with a decreased peak knee flexion angle (83.1°, 95%CI 81.4 to 84.8) compared with floorball players (86.5°, 95%CI 84.6 to 88.4) (P=0.016). There were no significant differences in height, weight or BMI between basketball and floorball players. Female athletes exhibited significantly greater valgus angles than males. This study revealed that proper knee control during jump-landing does not seem to develop in young athletes simply by playing the sport, despite the fact that jump-landings occur frequently in practice and games. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Prospective comparative study of two methods for fixation after distal femur corrective osteotomy for valgus deformity; retrograde intramedullary nailing versus less invasive stabilization system plating.

    PubMed

    Özcan, Çağrı; Sökücü, Sami; Beng, Kubilay; Çetinkaya, Engin; Demir, Bilal; Kabukçuoğlu, Yavuz Selim

    2016-10-01

    The aim of this study was to compare the radiological and functional results of two different methods of fixation for the correction of femoral valgus deformities. Patients who had undergone osteotomy and correction of a valgus deformity from 2007 to 2013 were prospectively followed. Thirty three patients (20 females, 13 males) with 39 lower limbs were included in the study. Seventeen lower limbs were treated with retrograde intramedullary nailing (IMN) and 22 with less invasive stabilization system plating. Standing orthoroentgenograms of the lower limbs were taken pre-operatively and at the final follow-up. mLDFA, aLDFA, mechanical axis deviation (MAD) were measured in this orthoroentgenograms. Knee osteoarthritis outcome score (KOOS) and knee range of motion were used pre-operatively and at the final follow-up as part of the evaluation of the clinical results. All patients duration of surgery, length of hospital stay were assessed. Operations were performed by two orthopedic surgeons. The choice of correction method for each patient was determined by the surgeon. Pre-operative and post-operative values were simultaneously measured by two additional orthopedic surgeons. The mean age of the patients was 26.2 years (18.0-51.0) in the plating group and 29.3 years (18.0-55.0) in the nailing group. Patients in the plating and nailing groups were followed up for 24.0 (12.0-60.0) and 27.8 (12.0-60.0) months. All patients were followed for a minimum of 12 months. No significant differences were observed between the groups in terms of age, sex, or duration of follow-up (p > 0.05) Comparison of the pre- and post-operative mLDFA, aLDFA, MAD, length of hospital stay, and duration of surgery between the plating group and nailing group, no significant difference was observed between the groups (p > 0.05). However, patients treated with retrograde IMN had significantly better post-operative results in terms of the KOOS and range of motion of the knee according to

  18. Landing Biomechanics in Participants With Different Static Lower Extremity Alignment Profiles

    PubMed Central

    Nguyen, Anh-Dung; Shultz, Sandra J.; Schmitz, Randy J.

    2015-01-01

    Context: Whereas static lower extremity alignment (LEA) has been identified as a risk factor for anterior cruciate ligament injury, little is known about its influence on joint motion and moments commonly associated with anterior cruciate ligament injury. Objective: To cluster participants according to combinations of LEA variables and compare these clusters in hip- and knee-joint kinematics and kinetics during the landing phase of a drop-jump task. Design: Descriptive laboratory study. Setting: Research laboratory. Patients or Other Participants: A total of 141 participants (50 men: age = 22.2 ± 2.8 years, height = 177.9 ± 9.3 cm, weight = 80.9 ± 13.3 kg; 91 women: age = 21.2 ± 2.6 years, height = 163.9 ± 6.6 cm, weight = 61.1 ± 8.7 kg). Main Outcome Measure(s): Static LEA included pelvic angle, femoral anteversion, quadriceps angle, tibiofemoral angle, genu recurvatum, tibial torsion, and navicular drop. Cluster analysis grouped participants according to their static LEA profiles, and these groups were compared on their hip- and knee-joint kinematics and external moments during the landing phase of a double-legged drop jump. Results: Three distinct clusters (C1–C3) were identified based on their static LEAs. Participants in clusters characterized with static internally rotated hip and valgus knee posture (C1) and externally rotated knee and valgus knee posture (C3) alignments demonstrated greater knee-valgus motion and smaller hip-flexion moments than the cluster with more neutral static alignment (C2). Participants in C1 also experienced greater hip internal-rotation and knee external-rotation moments than those in C2 and C3. Conclusions: Static LEA clusters that are positioned anatomically with a more rotated and valgus knee posture experienced greater dynamic valgus along with hip and knee moments during landing. Whereas static LEA contributes to differences in hip and knee rotational moments, sex may influence the differences in frontal-plane knee

  19. Do hip muscle weakness and dynamic knee valgus matter for the clinical evaluation and decision-making process in patients with patellofemoral pain?

    PubMed

    Rabelo, Nayra Deise Dos Anjos; Lucareli, Paulo Roberto Garcia

    Patellofemoral pain is a very common musculoskeletal condition. In the last years, evidence regarding this disease increased exponentially. Although widely investigated, this problem still frustrates patients and clinicians for having an unfavorable prognosis. Some gaps still exist in the understanding and managing of patellofemoral pain. Numerous cross-sectional association studies show an association between gluteus muscular strength and dynamic knee valgus in patients with patellofemoral pain. In spite of this biological plausibility, many evidences challenge the direct relationship between these factors. Recent studies have concluded that women with patellofemoral pain show muscular weakness of the hip based on the cross-sectional studies, however prospective studies indicate that hip weakness cannot be considered a risk for development of patellofemoral pain. In addition, some clinical trials have demonstrated that strength training of the gluteal muscles promotes significant improvement in symptoms but not alter the kinematics of the patients with patellofemoral pain. These findings cast doubt on whether the cause of this condition is really being treated, whether all individuals suffering from patellofemoral pain present dynamic knee valgus or if this is a disturbance present in only a subgroup of patients and whether the strengthening of the hip musculature is an option to consider for prevention of patellofemoral pain. Certainly, more studies should be conducted to clarify the influence of mechanical patterns on this condition, but with the existing evidence so far, the importance given to these issues in the evaluation and clinical decision on treatment of these patients seems questionable. Therefore, this masterclass explores the understanding about patellofemoral pain, highlighting mainly the importance of muscular strength and dynamic knee valgus, as well as other possible factors that must be consider during the evaluation and the decision making in

  20. Surgical correction of bilateral metacarpophalangeal valgus with curved osteotomies and type II external skeletal fixation in a seven-month-old alpaca.

    PubMed

    Schoonover, Mike J; Whitfield, Chase T; Rochat, Mark C; Streeter, Robert N; Sippel, Kate

    2016-09-20

    To report the successful surgical correction of severe bilateral metacarpophalangeal valgus angular limb deformities in a seven-month-old intact male alpaca cria using curved osteotomies stabilized with type II external skeletal fixation. Using a 21 mm crescentic shaped oscillating saw blade, bilateral osteotomies were performed in the distal metaphyses of the fused third and fourth metacarpal bones to correct valgus angular limb deformity of the metacarpophalangeal joints. Axial alignment of each limb was achieved by medially rotating the distal metacarpus in the frontal plane along the curved osteotomies. The osteotomies were stabilized using type II external skeletal fixators. The alpaca was immediately weight-bearing following the surgical procedure and no to minimal lameness was observed during healing of the osteotomies. Evaluation at five and 10 months following the surgery demonstrated acceptable axial alignment in the left forelimb while moderate to severe varus deformity (overcorrection) was observed in the right. Curved osteotomy of the distal metacarpus stabilized with type II external skeletal fixation can provide a favourable outcome in older alpaca crias affected with metacarpophalangeal angular limb deformities. Placement of the distal transfixation pins relative to the metacarpal physes should be carefully evaluated as overcorrection is possible, especially if growthpotential remains in only one physis of the fused third and fourth metacarpal bones.

  1. A Comparison of Two Designs of Postoperative Shoe on Function, Satisfaction, and Back Pain After Hallux Valgus Surgery.

    PubMed

    Patel, Shelain; Garg, Parag; Fazal, M Ali; Shahid, Muhammad S; Park, Derek H; Ray, Pinak S

    2018-06-01

    The reverse camber shoe is commonly used after hallux valgus corrective surgery to offload the forefoot but is associated with back pain and poor compliance. Recent designs of postoperative shoes may obviate the need for a reverse camber. The purpose of this study was to compare the effects of a reverse camber shoe and a noncambered shoe with transitional rigidity after hallux valgus correction. A cohort of 80 feet was prospectively studied undergoing surgery at a single NHS trust. The first 40 feet received the reverse cambered Jura Medical Off-loader Heel shoe and the subsequent 40 feet received the noncambered DonJoy Podalux shoe. No demographic differences existed between the groups and data were collected at 2 weeks, 6 weeks, and 6 months. The Manchester-Oxford Foot Questionnaire (MOXFQ), a 5-question survey and dichotomous question about back pain was used to assess clinical outcome and radiographs were reviewed by 2 orthopaedic surgeons to monitor for loss of correction. Both groups experienced comparable improvements in MOXFQ and shoe satisfaction from 2 weeks compared with 6 weeks. Six patients experienced back pain in the reverse cambered shoe group and none in the noncambered shoe group. Five patients stopped using the reverse cambered shoe during the first 6 weeks after surgery and none stopped using their prescribed noncambered shoe. No loss of corrections were observed in either group. Both shoe designs gave equal foot specific functional and radiological outcomes, but the noncambered shoe with transitional rigidity was associated with less back pain and better compliance. Level II: Prospective comparative study.

  2. Scarf versus chevron osteotomy for the correction of 1-2 intermetatarsal angle in hallux valgus: a systematic review and meta-analysis.

    PubMed

    Smith, Simon E; Landorf, Karl B; Butterworth, Paul A; Menz, Hylton B

    2012-01-01

    The chevron and scarf osteotomies are commonly used for the surgical management of hallux valgus (HV). However, there is debate as to whether one osteotomy provides more 1-2 intermetatarsal (1-2 IMA) correction than the other. The objective of this systematic review and meta-analysis was to compare the effectiveness of 3 types of first metatarsal osteotomy for reducing the 1-2 IMA in HV correction: the chevron osteotomy, the long plantar arm (modified) chevron osteotomy, and the scarf osteotomy. A systematic search for eligible studies was performed of the following databases: Medline, Embase (Ovid), CINAHL (EBSCO Host), and The Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Clinical Trials. Only English-language studies previous to May 2010 were included in the review. Additional hand and electronic content searches of relevant foot and orthopaedic journals were performed. Criteria for inclusion in this analysis included systematic reviews of randomized controlled trials, prospective and retrospective cohort studies, and case-control studies, as well as case-series studies involving the chevron, scarf, or long plantar arm chevron osteotomy of >20 participants with a minimum of 80% follow-up. Quality of evidence of the included studies was assessed with the Grading of Recommendations Assessment, Development and Evaluation system. All pooled analyses were based on a fixed effects model. There was a total of 1351 participants who underwent either a chevron (n = 1028), scarf (n = 300), or long plantar arm chevron osteotomy (n = 23). Only one study for the long plantar arm chevron group fitted the eligibility criteria for this review; however, it was not amenable to meta-analysis. The chevron osteotomy was associated with a mean reduction of 1-2 IMA from preoperative to postoperative of 5.33° (95% confidence interval, 5.12 to 5.54, p < .001), and the scarf osteotomy was associated with a mean reduction of 6.21° (95% confidence

  3. Effect of distal ulnar collateral ligament tear pattern on contact forces and valgus stability in the posteromedial compartment of the elbow.

    PubMed

    Hassan, Sheref E; Parks, Brent G; Douoguih, Wiemi A; Osbahr, Daryl C

    2015-02-01

    It is not known whether the pattern of ulnar collateral ligament (UCL) tear affects elbow biomechanics. There will be a significant change in elbow biomechanics with 50% proximal but not 50% distal simulated rupture of the UCL. Controlled laboratory study. Pressure sensors in the posteromedial elbow joint of 25 male cadaveric elbows (average age, 54.9 years; range, 26-66 years) were used to measure contact area, pressure, and valgus torque at 90° and 30° of elbow flexion. Thirteen specimens were tested with the UCL intact, then with proximal-to-distal detachment of 50%, and then with proximal-to-distal detachment of 100% of the anterior band of the UCL from the ulnar attachment. This method was repeated in the remaining 12 specimens in a distal-to-proximal direction. With 50% proximal-to-distal detachment, contact area decreased significantly versus intact at 90° (91.3 ± 23.6 vs 112.2 ± 26.0 mm(2); P < .001) and 30° (69.3 ± 14.8 vs 83.1 ± 21.6 mm(2); P < .001) of elbow flexion; the center of pressure (COP) moved significantly proximally versus intact at 90° (3.8 ± 2.5 vs 5.4 ± 2.3 mm; P < .001) and 30° (5.9 ± 2.8 vs 7.4±1.9 mm; P < .001). With 50% distal-to-proximal UCL detachment versus intact, no significant change was observed in contact area, movement of the COP, or valgus laxity at either flexion position. With 100% proximal-to-distal and distal-to-proximal detachment, significant change in contact area, movement of the COP, and valgus laxity versus intact was found at 90° and 30° of elbow flexion (P < .05). No significant difference in contact pressure was observed in any test conditions. Significant change in contact area and proximal movement of the COP with 50% proximal UCL detachment and the lack of significant change with 50% distal UCL detachment suggest that the proximal half of the UCL ulnar footprint has a primary role in maintaining posteromedial elbow biomechanics. The findings suggest that surgical reconstruction should aim to

  4. Postoperative limb alignment and its determinants after minimally invasive Oxford medial unicompartmental knee arthroplasty.

    PubMed

    Mullaji, Arun B; Shetty, Gautam M; Kanna, Raj

    2011-09-01

    One hundred twenty-two consecutive minimally invasive Oxford phase 3 medial unicompartmental knee arthroplasties in 109 patients were evaluated for postoperative limb alignment and the influence of factors such as preoperative limb alignment, age, body mass index, sex, insert thickness, and surgeon's experience. The mean mechanical preoperative hip-knee-ankle (HKA) angle of 172.2° ± 3.1° improved to 177.1° ± 2.9° postoperatively. In 75% of the limbs, the HKA angle was restored to within an acceptable alignment of 177° ± 3°, 14% of the limbs were in excessive varus (<174°), and 11% were in valgus (>180°). Only preoperative HKA angle was predictive of postoperative HKA angle. Although most of the limbs had acceptable limb alignment after unicompartmental knee arthroplasty, limbs with more severe preoperative varus deformity had a tendency to remain in excessive varus, and limbs with lesser preoperative varus deformity had a greater tendency to go into valgus postoperatively. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. A study of anatomy of distal femur pertaining to total knee replacement: an analysis, conclusions and recommendations.

    PubMed

    Kumar, K; Sharma, D

    2018-04-01

    Multiple landmarks including the transepicondylar axis (TEA), posterior condylar axis (PCA) and anterior trochlear line (TL) have been used to set up the femoral component rotation, but each is faced with its own practical obstacle that limits its usage. Also a common practice is to set the femoral component rotation at 3° external rotation to PCA and valgus resection angle at 5°-7° to anatomical axis of femur. For the reason that the anatomy of each knee is different, it may not be justified to practice such a set protocol in all cases. The aim of the study was to compare the anatomical landmarks used to set up the femoral component rotation and to study the variability in the different anatomical relationships relevant to total knee replacement. The study had 52 patients (94 knees) with grade IV osteoarthritis. Full-length lower limb scanogram and 1 mm cross-sectional cuts of distal femur were taken. aTEA, sTEA, PCL, TL, CTA, PCA, TLA and valgus angles were taken for all knees. aTEA is identifiable in all cases but sTEA in only 59 knees (62.77%). Correspondingly, CTA is calculable in all knees and PCA in 62.77% cases. Mean CTA and mean PCA were 5.4° ± 1.88° SD and 0.71° ± 1.95° SD, respectively. Mean angle between aTEA and sTEA was 4.88. TL is a line difficult to draw because of high incidence of anterior osteophytes, making CTA a more reliable parameter than TLA. Mean TLA was 10.31° ± 3.52° SD. Mean valgus resection angle was 4.86° ± 2.53° SD. Gender- or side-based differences in any of these values were not statistically different. Using aTEA or sTEA can make a big difference in femoral component rotation; therefore, whether aTEA or sTEA should be used needs to be further investigated. CTA, PCA and valgus resection angle need to be individually calculated for each knee. Use of TLA is not recommended.

  6. Minimal Clinically Important Differences for American Orthopaedic Foot & Ankle Society Score in Hallux Valgus Surgery.

    PubMed

    Chan, Hiok Yang; Chen, Jerry Yongqiang; Zainul-Abidin, Suraya; Ying, Hao; Koo, Kevin; Rikhraj, Inderjeet Singh

    2017-05-01

    The American Orthopaedic Foot & Ankle Society (AOFAS) score is one of the most common and adapted outcome scales in hallux valgus surgery. However, AOFAS is predominantly physician based and not patient based. Although it may be straightforward to derive statistical significance, it may not equate to the true subjective benefit of the patient's experience. There is a paucity of literature defining MCID for AOFAS in hallux valgus surgery although it could have a great impact on the accuracy of analyzing surgical outcomes. Hence, the primary aim of this study was to define the Minimal Clinically Important Difference (MCID) for the AOFAS score in these patients, and the secondary aim was to correlate patients' demographics to the MCID. We conducted a retrospective cross-sectional study. A total of 446 patients were reviewed preoperatively and followed up for 2 years. An anchor question was asked 2 years postoperation: "How would you rate the overall results of your treatment for your foot and ankle condition?" (excellent, very good, good, fair, poor, terrible). The MCID was derived using 4 methods, 3 from an anchor-based approach and 1 from a distribution-based approach. Anchor-based approaches were (1) mean difference in 2-year AOFAS scores of patients who answered "good" versus "fair" based on the anchor question; (2) mean change of AOFAS score preoperatively and at 2-year follow-up in patients who answered good; (3) receiver operating characteristic (ROC) curves method, where the area under the curve (AUC) represented the likelihood that the scoring system would accurately discriminate these 2 groups of patients. The distribution-based approach used to calculate MCID was the effect size method. There were 405 (90.8%) females and 41 (9.2%) males. Mean age was 51.2 (standard deviation [SD] = 13) years, mean preoperative BMI was 24.2 (SD = 4.1). Mean preoperative AOFAS score was 55.6 (SD = 16.8), with significant improvement to 85.7 (SD = 14.4) in 2 years ( P value

  7. Use of 3D Printed Bone Plate in Novel Technique to Surgically Correct Hallux Valgus Deformities

    PubMed Central

    Smith, Kathryn E.; Dupont, Kenneth M.; Safranski, David L.; Blair, Jeremy; Buratti, Dawn; Zeetser, Vladimir; Callahan, Ryan; Lin, Jason; Gall, Ken

    2016-01-01

    Three-dimensional (3-D) printing offers many potential advantages in designing and manufacturing plating systems for foot and ankle procedures that involve small, geometrically complex bony anatomy. Here, we describe the design and clinical use of a Ti-6Al-4V ELI bone plate (FastForward™ Bone Tether Plate, MedShape, Inc., Atlanta, GA) manufactured through 3-D printing processes. The plate protects the second metatarsal when tethering suture tape between the first and second metatarsals and is a part of a new procedure that corrects hallux valgus (bunion) deformities without relying on doing an osteotomy or fusion procedure. The surgical technique and two clinical cases describing the use of this procedure with the 3-D printed bone plate are presented within. PMID:28337049

  8. Hallux valgus, ankle osteoarthrosis and adult acquired flatfoot deformity: a review of three common foot and ankle pathologies and their treatments

    PubMed Central

    Crevoisier, Xavier; Assal, Mathieu; Stanekova, Katarina

    2016-01-01

    The pathogenesis of hallux valgus deformity is multifactorial. Conservative treatment can alleviate pain but is unable to correct the deformity. Surgical treatment must be adapted to the type and severity of the deformity. Success of surgical treatment ranges from 80% to 95%, and complication rates range from 10% to 30%. Ankle osteoarthrosis most commonly occurs as a consequence of trauma. Ankle arthrodesis and total ankle replacement are the most common surgical treatments of end stage ankle osteoarthrosis. Both types of surgery result in similar clinical improvement at midterm; however, gait analysis has demonstrated the superiority of total ankle replacement over arthrodesis. More recently, conservative surgery (extraarticular alignment osteotomies) around the ankle has gained popularity in treating early- to mid-stage ankle osteoarthrosis. Adult acquired flatfoot deformity is a consequence of posterior tibial tendon dysfunction in 80% of cases. Classification is based upon the function of the tibialis posterior tendon, the reducibility of the deformity, and the condition of the ankle joint. Conservative treatment includes orthotics and eccentric muscle training. Functional surgery is indicated for treatment in the early stages. In case of fixed deformity, corrective and stabilising surgery is performed. Cite this article: Crevoisier X, Assal M, Stanekova K. Hallux valgus, ankle osteoarthrosis and adult acquired flatfoot deformity: a review of three common foot and ankle pathologies and their treatments. EFORT Open Rev 2016;1:58–64. DOI: 10.1302/2058-5241.1.000015. PMID:28461929

  9. Surgical treatment of subacute and chronic valgus instability in multiligament-injured knees with superficial medial collateral ligament reconstruction using Achilles allografts: a quantitative analysis with a minimum 2-year follow-up.

    PubMed

    Liu, Xin; Feng, Hua; Zhang, Hui; Hong, Lei; Wang, Xue Song; Zhang, Jin; Shen, Jie Wei

    2013-05-01

    Symptomatic medial collateral ligament (MCL) instability is rare, and it is frequently associated with multiligament injuries. Most clinical investigations have failed to clearly define the specific objective outcome measures assessing the stability of the MCL quantitatively before and after the reconstruction procedure. To quantitatively evaluate the early clinical outcomes of patients with valgus instability of knee joints who had undergone superficial MCL reconstruction using Achilles tendon allografts. Case series; Level of evidence, 4. From August 2005 to December 2010, 19 consecutive patients with MCL injuries were included in this study. The inclusion criteria were (1) a subacute or chronic MCL injury, with a time from initial injury to surgery of longer than 3 weeks, and (2) valgus laxity graded C or D according to the International Knee Documentation Committee (IKDC). All patients underwent superficial MCL reconstruction using Achilles tendon allografts. To evaluate the laxity of the MCL preoperatively and postoperatively, valgus stress radiographs using a Telos device were used. Other assessments included the IKDC subjective functional evaluation and Lysholm score estimation. Sixteen of the 19 patients (12 men and 4 women) were available for final follow-up. The median age of the patients was 37 years (range, 19-53 years); mean body mass index (BMI) was 26.4 (range, 21.7-29.4). The mean time from injury to surgery was 15.9 months (range, 24 days to 84 months), and median follow-up period was 34 months (range, 24-67 months). The mean medial knee laxity (side-to-side difference) was 8.9 ± 3.2 mm (range, 6-15.9 mm) preoperatively and 1.1 ± 0.9 mm (range, -1.1 to 3.2 mm) postoperatively (P < .001). The preoperative mean IKDC subjective knee functional score was 49.8 ± 6.9 (range, 31-57.5), while the postoperative functional score was 84.3 ± 6.0 (range, 71.3-93.1) (P < .001). The mean Lysholm score was 69.3 ± 5.9 (range, 55-78) preoperatively and 88.6

  10. Equilibrium contact angle or the most-stable contact angle?

    PubMed

    Montes Ruiz-Cabello, F J; Rodríguez-Valverde, M A; Cabrerizo-Vílchez, M A

    2014-04-01

    It is well-established that the equilibrium contact angle in a thermodynamic framework is an "unattainable" contact angle. Instead, the most-stable contact angle obtained from mechanical stimuli of the system is indeed experimentally accessible. Monitoring the susceptibility of a sessile drop to a mechanical stimulus enables to identify the most stable drop configuration within the practical range of contact angle hysteresis. Two different stimuli may be used with sessile drops: mechanical vibration and tilting. The most stable drop against vibration should reveal the changeless contact angle but against the gravity force, it should reveal the highest resistance to slide down. After the corresponding mechanical stimulus, once the excited drop configuration is examined, the focus will be on the contact angle of the initial drop configuration. This methodology needs to map significantly the static drop configurations with different stable contact angles. The most-stable contact angle, together with the advancing and receding contact angles, completes the description of physically realizable configurations of a solid-liquid system. Since the most-stable contact angle is energetically significant, it may be used in the Wenzel, Cassie or Cassie-Baxter equations accordingly or for the surface energy evaluation. © 2013 Elsevier B.V. All rights reserved.

  11. Longitudinal changes of angle configuration in primary angle-closure suspects: the Zhongshan Angle-Closure Prevention Trial.

    PubMed

    Jiang, Yuzhen; Chang, Dolly S; Zhu, Haogang; Khawaja, Anthony P; Aung, Tin; Huang, Shengsong; Chen, Qianyun; Munoz, Beatriz; Grossi, Carlota M; He, Mingguang; Friedman, David S; Foster, Paul J

    2014-09-01

    To determine longitudinal changes in angle configuration in the eyes of primary angle-closure suspects (PACS) treated by laser peripheral iridotomy (LPI) and in untreated fellow eyes. Longitudinal cohort study. Primary angle-closure suspects aged 50 to 70 years were enrolled in a randomized, controlled clinical trial. Each participant was treated by LPI in 1 randomly selected eye, with the fellow eye serving as a control. Angle width was assessed in a masked fashion using gonioscopy and anterior segment optical coherence tomography (AS-OCT) before and at 2 weeks, 6 months, and 18 months after LPI. Angle width in degrees was calculated from Shaffer grades assessed under static gonioscopy. Angle configuration was also evaluated using angle opening distance (AOD250, AOD500, AOD750), trabecular-iris space area (TISA500, TISA750), and angle recess area (ARA) measured in AS-OCT images. No significant difference was found in baseline measures of angle configuration between treated and untreated eyes. At 2 weeks after LPI, the drainage angle on gonioscopy widened from a mean of 13.5° at baseline to a mean of 25.7° in treated eyes, which was also confirmed by significant increases in all AS-OCT angle width measures (P<0.001 for all variables). Between 2 weeks and 18 months after LPI, a significant decrease in angle width was observed over time in treated eyes (P<0.001 for all variables), although the change over the first 5.5 months was not statistically significant for angle width measured under gonioscopy (P = 0.18), AOD250 (P = 0.167) and ARA (P = 0.83). In untreated eyes, angle width consistently decreased across all follow-up visits after LPI, with a more rapid longitudinal decrease compared with treated eyes (P values for all variables ≤0.003). The annual rate of change in angle width was equivalent to 1.2°/year (95% confidence interval [CI], 0.8-1.6) in treated eyes and 1.6°/year (95% CI, 1.3-2.0) in untreated eyes (P<0.001). Angle width of treated eyes

  12. Patellofemoral pain in athletes

    PubMed Central

    Petersen, Wolf; Rembitzki, Ingo; Liebau, Christian

    2017-01-01

    Patellofemoral pain (PFP) is a frequent cause of anterior knee pain in athletes, which affects patients with and without structural patellofemoral joint (PFJ) damage. Most younger patients do not have any structural changes to the PFJ, such as an increased Q angle and a cartilage damage. This clinical entity is known as patellofemoral pain syndrome (PFPS). Older patients usually present with signs of patellofemoral osteoarthritis (PFOA). A key factor in PFPS development is dynamic valgus of the lower extremity, which leads to lateral patellar maltracking. Causes of dynamic valgus include weak hip muscles and rearfoot eversion with pes pronatus valgus. These factors can also be observed in patients with PFOA. The available evidence suggests that patients with PFP are best managed with a tailored, multimodal, nonoperative treatment program that includes short-term pain relief with nonsteroidal anti-inflammatory drugs (NSAIDs), passive correction of patellar maltracking with medially directed tape or braces, correction of the dynamic valgus with exercise programs that target the muscles of the lower extremity, hip, and trunk, and the use of foot orthoses in patients with additional foot abnormalities. PMID:28652829

  13. Treatment of post-traumatic elbow deformities in children with the Ilizarov distraction osteogenesis technique.

    PubMed

    Özkan, Cenk; Deveci, Mehmet Ali; Tekin, Mustafa; Biçer, Ömer Sunkar; Gökçe, Kadir; Gülşen, Mahir

    2017-01-01

    The present study assessed functional and radiographic outcomes of distraction osteogenesis treatment of post-traumatic elbow deformities in children. Eight children were treated between 2008 and 2013 for post-traumatic elbow deformities using distraction osteogenesis. Mean age at time of operation was 10.9 years. Six patients had varus and 2 had valgus deformity. Magnitude of correction, fixator index, complications, carrying angle, and elbow range of motion were assessed. Functional results were graded according to protocol of Bellemore et al. Mean follow-up was 43 months. Mean preoperative varus deformity in 6 patients was 29.2° and valgus deformity in 2 patients was 28.5°. Preoperative flexion and extension of elbow were 123.8° and -10.6°, respectively. Mean carrying angle was 9° valgus at last follow-up. Mean flexion and extension were 134.4° and -6.0°, respectively. Change in carrying angle was statistically significant (p = 0.002). There were 2 grade 1 pin tract infections and 1 diaphyseal fracture of humerus. Functional outcome was rated excellent in 7 patients and good in 1 patient. Ilizarov distraction osteogenesis is a valuable alternative in treatment of elbow deformities in children. The surgical technique is simple and correction is adjustable. Gradual correction prevents possible neurovascular complications and minimally invasive surgery produces less scarring. Compliance of patient and family is key factor in the success of the outcome. Level IV, therapeutic study. Copyright © 2016 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  14. Seismic triplication used to reveal slab subduction that had disappeared in the late Mesozoic beneath the northeastern South China Sea

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoran; Li, Qiusheng; Li, Guohui; Zhou, Yuanze; Ye, Zhuo; Zhang, Hongshuang

    2018-03-01

    We provided a new study of the seismic velocity structure of the mantle transition zone (MTZ) beneath the northeastern South China Sea using P-wave triplications from two earthquakes at the central Philippines recorded by the Chinese Digital Seismic Network. Through fitting the observed and theoretical triplications modeled by the dynamic ray tracing method for traveltimes, and the reflectivity method for synthetic waveforms using grid-searching method, best-fit velocity models based on IASP91 were obtained to constrain the P-wave velocity structure of the MTZ. The models show that a high-velocity anomaly (HVA) resides at the bottom of MTZ. The HVA is 215 km to 225 km thick, with a P-wave velocity increment of 1.0% between 450 km and 665 km or 675 km transition and increase by 2.5-3.5% at 665 km or 675 km depth. The P-wave velocity increment ranges from approximately 0.3% to 0.8% below the 665 km or 675 km. We proposed that the HVA in the MTZ was caused by the broken fragments of a diving oceanic plate falling into the MTZ at a high angle, and/or by unstable thick continental lithosphere dropping into the MTZ sequentially or almost simultaneously.

  15. Plasma homovanillic acid levels in first-episode schizophrenia. Psychopathology and treatment response.

    PubMed

    Koreen, A R; Lieberman, J; Alvir, J; Mayerhoff, D; Loebel, A; Chakos, M; Amin, F; Cooper, T

    1994-02-01

    To examine plasma homovanillic acid (pHVA) levels in first-episode schizophrenia, to compare pHVA levels in patients and controls, and to assess the association of pHVA levels with psychopathology and treatment response. Forty-one patients entered the study, and pHVA levels were measured at baseline and on a weekly basis for up to 6 weeks of open standardized neuroleptic treatment. Psychopathology was evaluated with the Schedule for Affective Disorders and Schizophrenia, the Scale for Assessment of Negative Symptoms, and the Clinical Global Impressions scale. Ten healthy controls were used for comparison of baseline pHVA levels. No differences were observed between patients and controls. Baseline pHVA level was not associated with psychopathology but was associated with time to reach remission. Baseline pHVA levels and week-1 pHVA levels were higher in responders than nonresponders. Regardless of responsiveness, female participants had higher pHVA levels than male participants throughout the study. The pattern of pHVA levels with treatment was similar in all patients with a short-term rise initially and then a decrease toward baseline values. These findings suggest that pHVA levels have prognostic significance for response and time to reach remission. Qualitative and quantitative differences between first-episode patients' pHVA levels and studies using a long-term, neuroleptic-exposed population suggest that changes occur with neuroleptic treatment or the progression of the illness.

  16. The influence of local bone quality on fracture pattern in proximal humerus fractures.

    PubMed

    Mazzucchelli, Ruben A; Jenny, Katharina; Zdravkovic, Vilijam; Erhardt, Johannes B; Jost, Bernhard; Spross, Christian

    2018-02-01

    Bone mineral density and fracture morphology are widely discussed and relevant factors when considering the different treatment options for proximal humerus fractures. It was the aim of this study to investigate the influence of local bone quality on fracture patterns of the Neer classification as well as on fracture impaction angle in these injuries. All acute, isolated and non-pathological proximal humerus fractures admitted to our emergency department were included. The fractures were classified according to Neer and the humeral head impaction angle was measured. Local bone quality was assessed using the Deltoid Tuberosity Index (DTI). The distribution between DTI and fracture pattern was analysed. 191 proximal humerus fractures were included (61 men, mean age 59 years; 130 women, mean age 69.5). 77 fractures (40%) were classified as one-part, 72 (38%) were two-part, 24 (13%) were three- and four-part and 18 (9%) were fracture dislocations. 30 fractures (16%) were varus impacted, whereas 45 fractures (24%) were classified as valgus impacted. The mean DTI was 1.48. Valgus impaction significantly correlated with good bone quality (DTI ≥ 1.4; p = 0.047) whereas no such statistical significance was found for the Neer fracture types. We found that valgus impaction significantly depended on good bone quality. However, neither varus impaction nor any of the Neer fracture types correlated with bone quality. We conclude that the better bone quality of valgus impacted fractures may be a reason for their historically benign amenability to ORIF. On the other hand, good local bone quality does not prevent fracture comminution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Ulnar collateral ligament reconstruction using bisuspensory fixation: a biomechanical comparison with the docking technique.

    PubMed

    Jackson, Timothy J; Adamson, Gregory J; Peterson, Alexander; Patton, John; McGarry, Michelle H; Lee, Thay Q

    2013-05-01

    Many ulnar collateral ligament (UCL) reconstruction techniques have been created and biomechanically tested. Single-bundle reconstructions aim to re-create the important anterior bundle of the UCL. To date, no technique has utilized suspensory fixation on the ulnar and humeral sides to create a single-bundle reconstruction. The bisuspensory technique will restore valgus laxity to its native state, with comparable load-to-failure characteristics to the docking technique. Controlled laboratory study. Six matched pairs of fresh-frozen cadaveric elbows were randomized to undergo UCL reconstruction using either the docking technique or a novel single-bundle bisuspensory technique. Valgus laxity and rotation measurements were quantified using a MicroScribe 3DLX digitizer at various flexion angles for the native ligament, transected ligament, and 1 of the 2 tested reconstructed ligaments. Laxity testing was performed from maximum extension to 120° of flexion. Each reconstruction was then tested to failure, and the method of failure was recorded. Valgus laxity was restored to the intact state at all degrees of elbow flexion for both the docking and bisuspensory techniques. In load-to-failure testing, there was no significant difference with regard to stiffness, ultimate torque, ultimate torque angle, energy absorbed, and applied moment to reach 10° of valgus. Yield torques for the bisuspensory and docking reconstructions were 18.7 ± 7.8 N·m and 18.6 ± 4.4 N·m, respectively (P = .95). The ultimate torque for the bisuspensory technique measured 26.5 ± 9.2 N·m and for the docking technique measured 25.1 ± 7.1 N·m (P = .78). The bisuspensory fixation technique, a reproducible single-bundle reconstruction, was able to restore valgus laxity to the native state, with similar load-to-failure characteristics as the docking technique. This reconstruction technique could be considered in a clinical setting as a primary method of UCL reconstruction or as a backup fixation

  18. Landing Kinematics in Elite Male Youth Soccer Players of Different Chronologic Ages and Stages of Maturation.

    PubMed

    Read, Paul J; Oliver, Jon L; De Ste Croix, Mark B A; Myer, Gregory D; Lloyd, Rhodri S

    2018-04-01

      Despite the high frequency of knee injuries in athletes, few researchers have studied the effects of chronologic age and stage of maturation on knee-joint kinematics in male youth soccer players.   To use a coach-friendly screening tool to examine knee-valgus scores for players of different ages and at different stages of maturation.   Cross-sectional study.   Academy soccer clubs.   A total of 400 elite male youth soccer players aged 10 to 18 years categorized by chronologic age and stage of maturation based on their years from peak height velocity (PHV).   Knee valgus was evaluated during the tuck-jump assessment via 2-dimensional analysis. Frontal-plane projection angles were subjectively classified as minor (<10°), moderate (10°-20°), or severe (>20°), and using these classifications, we scored knee valgus in the tuck jump as 0 ( no valgus), 1 ( minor), 2 ( moderate), or 3 ( severe).   A trend toward higher valgus scores was observed in the younger age groups and the pre-PHV group. The lowest frequency of no valgus occurred in the U18 and post-PHV groups. The highest percentages of severe scores were in the U13 and pre-PHV groups for the right limb. Knee-valgus scores were lower for both lower extremities in the U18 group than in all other age groups ( P < .001) except the U16 group. Scores were lower for the post-PHV than the pre-PHV group for the right limb ( P < .001) and both pre-PHV and circa-PHV groups for the left limb ( P < .001). Noteworthy interlimb asymmetries were evident in the U14, U15, and circa-PHV groups.   Reductions in knee valgus with incremental age and during the later stages of maturation indicated that this risk factor was more prevalent in younger players. Interlimb asymmetry may also emerge around the time of the peak growth spurt and early adolescence, potentially increasing the risk of traumatic injury.

  19. Plasma-free homovanillic acid: within- and across-day stability in children and adults with Tourette's syndrome.

    PubMed

    Riddle, M A; Leckman, J F; Anderson, G M; Ort, S I; Hardin, M T; Stevenson, J; Cohen, D J

    1987-06-01

    Within- and across-day stability of plasma-free homovanillic acid (pHVA) was assessed in children and adults with Tourette's syndrome. A diurnal fall in pHVA was observed in 13 of 15 subjects. There was a small but significant (p less than .0001) decrease (8%) in mean morning pHVA levels obtained just 20 minutes apart (8:30 A.M. and 8:50 A.M.). A substantial and significant (p less than .001) mean decrease in pHVA (25%) was observed when samples obtained between 8:00 and 8:30 A.M. were compared with samples obtained at 12:00 noon. Changes in pHVA levels observed during the afternoon (between 12:00 noon and 4:00 P.M.) were small, nondirectional, and nonsignificant. Repeated measurement of morning pHVA in the same individual after 24 or more hours revealed marked increases or decreases in many individuals, suggesting that morning pHVA is not a stable measure. The results of this and previous studies suggest that pHVA obtained at 12:00 noon or later in the day may be a more reliable measure of centrally produced HVA. Further studies are needed regarding the stability of pHVA over time.

  20. Longitudinal Changes of Angle Configuration in Primary Angle-Closure Suspects

    PubMed Central

    Jiang, Yuzhen; Chang, Dolly S.; Zhu, Haogang; Khawaja, Anthony P.; Aung, Tin; Huang, Shengsong; Chen, Qianyun; Munoz, Beatriz; Grossi, Carlota M.

    2015-01-01

    Objective To determine longitudinal changes in angle configuration in the eyes of primary angle-closure suspects (PACS) treated by laser peripheral iridotomy (LPI) and in untreated fellow eyes. Design Longitudinal cohort study. Participants Primary angle-closure suspects aged 50 to 70 years were enrolled in a randomized, controlled clinical trial. Methods Each participant was treated by LPI in 1 randomly selected eye, with the fellow eye serving as a control. Angle width was assessed in a masked fashion using gonioscopy and anterior segment optical coherence tomography (AS-OCT) before and at 2 weeks, 6 months, and 18 months after LPI. Main Outcome Measures Angle width in degrees was calculated from Shaffer grades assessed under static gonioscopy. Angle configuration was also evaluated using angle opening distance (AOD250, AOD500, AOD750), trabecular-iris space area (TISA500, TISA750), and angle recess area (ARA) measured in AS-OCT images. Results No significant difference was found in baseline measures of angle configuration between treated and untreated eyes. At 2 weeks after LPI, the drainage angle on gonioscopy widened from a mean of 13.5° at baseline to a mean of 25.7° in treated eyes, which was also confirmed by significant increases in all AS-OCT angle width measures (P<0.001 for all variables). Between 2 weeks and 18 months after LPI, a significant decrease in angle width was observed over time in treated eyes (P<0.001 for all variables), although the change over the first 5.5 months was not statistically significant for angle width measured under gonioscopy (P = 0.18), AOD250 (P = 0.167) and ARA (P = 0.83). In untreated eyes, angle width consistently decreased across all follow-up visits after LPI, with a more rapid longitudinal decrease compared with treated eyes (P values for all variables ≤0.003). The annual rate of change in angle width was equivalent to 1.2°/year (95% confidence interval [CI], 0.8–1.6) in treated eyes and 1.6°/year (95% CI, 1

  1. Early results using a biodegradable magnesium screw for modified chevron osteotomies.

    PubMed

    Plaass, Christian; Ettinger, Sarah; Sonnow, Lena; Koenneker, Soeren; Noll, Yvonne; Weizbauer, Andreas; Reifenrath, Janin; Claassen, Leif; Daniilidis, Kiriakos; Stukenborg-Colsman, Christina; Windhagen, Henning

    2016-12-01

    This is the first larger study analyzing the use of magnesium-based screws for fixation of modified Chevron osteotomies in hallux valgus surgery. Forty-four patients (45 feet) were included in this prospective study. A modified Chevron osteotomy was performed on every patient and a magnesium screw used for fixation. The mean clinical follow up was 21.4 weeks. The mean age of the patients was 45.5 years. Forty patients could be provided with the implant, in four patients the surgeon decided to change to a standard metallic implant. The AOFAS, FAAM and pain NRS-scale improved markedly. The hallux valgus angle, intermetatarsal angle and sesamoid position improved significantly. Seven patients showed dorsal subluxation, rotation or medial shifting of the metatarsal heads within the first 3 months. One of these patients was revised, in all others the findings were considered clinically not significant or the patients refused revision. This study shows the feasibility of using magnesium screws in hallux valgus-surgery. Surgeons starting with the use of these implants should be aware of the proper handling of these implants and should know about corrosion effects during healing and its radiographic appearance. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2207-2214, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  2. Assessing coronal laxity in extension and flexion at a minimum of 10 years after primary total knee arthroplasty.

    PubMed

    Yoshihara, Yasushi; Arai, Yuji; Nakagawa, Shuji; Inoue, Hiroaki; Ueshima, Keiichiro; Fujiwara, Hiroyoshi; Oda, Ryo; Taniguchi, Daigo; Kubo, Toshikazu

    2016-08-01

    Favourable long-term results after total knee arthroplasty (TKA) require appropriate soft tissue balance. However, the relationships between long-term results after TKA surgery and mediolateral laxities at extension and at 90° flexion remain unknown. This study therefore quantitatively assessed ligament balance at extension and at 90° knee flexion at least 10 years after primary TKA, as well as clarifying the relationships between long-term outcomes and mediolateral laxities. This study included 49 knees (19 CR type and 30 PS type) of 33 patients followed up for at least 10 years after TKA at our hospital. Plain radiographs were obtained with about 150 N of varus or valgus stress using a Telos arthrometer at extension. At 90° flexion, epicondylar views were obtained under a 1.5-kg load and with about 10 kg of varus or valgus stress. Lateral laxity of about 5° was observed in both extension and flexion, with total laxities of varus and valgus stress each less than 10°. Postoperative clinical outcomes were good, with significant improvements in extension angle, femorotibial angle, and KSS, and no loosening in any knee. Good long-term results of TKA can be obtained with a lateral laxity of about 5°, equivalent to that of healthy knees. III.

  3. Etiologic heterogeneity of the psychoses: is there a dopamine psychosis?

    PubMed

    Garver, D L; Steinberg, J L; McDermott, B E; Yao, J K; Ramberg, J E; Lewis, S; Kingsbury, S J

    1997-03-01

    The distribution of drug-free plasma homovanillic acid (pHVA) concentrations was studied in a sample of psychotic patients, some of whom were selected for good prognostic features. Baseline pHVA was bimodally distributed, suggesting two different patient populations. The high-pHVA patients showed periods of better functioning and/or fewer symptoms 5 years before admission (p < .05) and had a more rapid (p < .05) and complete (p < .001) subacute neuroleptic response than lower-pHVA psychotics. High-pHVA psychotics did not differ in other aspects of demographics or clinical presentation from lower-pHVA psychotics. Compared to the general population, there were more psychotics in the families of high-pHVA patients (p < .005). Rapid antipsychotic response by high-pHVA psychotics is consistent with blockade of the effects of excess synaptic dopamine at D2 receptors for these patients. Results are discussed in the context of the syndromic heterogeneity of the psychoses.

  4. Measurement of varus-valgus and internal-external rotational knee laxities in vivo--Part II: relationship with anterior-posterior and general joint laxity in males and females.

    PubMed

    Shultz, Sandra J; Shimokochi, Yohei; Nguyen, Anh-Dung; Schmitz, Randy J; Beynnon, Bruce D; Perrin, David H

    2007-08-01

    We examined sex differences in general joint laxity (GJL), and anterior-posterior displacement (ANT-POST), varus-valgus rotation (VR-VL), and internal-external rotation (INT-EXT) knee laxities, and determined whether greater ANT and GJL predicted greater VR-VL and INT-EXT. Twenty subjects were measured for GJL, and scored on a scale of 0-9. ANT and POST were measured using a standard knee arthrometer at 133 N. VR-VL and INT-EXT were measured using a custom joint laxity testing device, defined as the angular displacements (deg) of the tibia relative to the femur produced by 0-10 Nm of varus-valgus torques, and 0-5 Nm of internal-external torques, respectively. INT-EXT were measured during both non-weight-bearing (NWB) and weight-bearing (WB = 40% body weight) conditions while VR-VL were measured NWB. All laxity measures were greater for females compared to males except for POST. ANT and GJL positively predicted 62.5% of the variance in VR-VL and 41.8% of the variance in WB INT-EXT. ANT was the sole predictor of INT-EXT in NWB, explaining 42.3% of the variance. These findings suggest that subjects who score higher on clinical measures of GJL and ANT are also likely to have greater VR-VL and INT-EXT knee laxities.

  5. Hallux Valgus, By Nature or Nurture? A Twin Study.

    PubMed

    Munteanu, Shannon E; Menz, Hylton B; Wark, John D; Christie, Jemma J; Scurrah, Katrina J; Bui, Minh; Erbas, Bircan; Hopper, John L; Wluka, Anita E

    2017-09-01

    To evaluate the contributions of shared but unmeasured genetic and environmental factors to hallux valgus (HV). Between 2011 and 2012, 74 monozygotic (MZ) and 56 dizygotic (DZ) female twin pairs self-reported HV and putative risk factors, including footwear use across their lifespan. Estimates of casewise concordance (P C ), correlation (ρ), and odds ratios (ORs) were calculated, adjusting for age and other risk factors, and compared between MZ and DZ pairs using logistic regression, generalized estimating equations, and a maximum likelihood-based method, respectively. A total of 70 participants (27%) reported HV, with 12 MZ and 7 DZ pairs being concordant. After adjusting for age, twins were correlated (ρ = 0.27 [95% confidence interval (95% CI) 0.08, 0.46]) and concordant (P C  = 0.45 [95% CI 0.29, 0.61]; mean age 58 years), with no difference between MZ and DZ pairs (P = 0.7). HV was associated with regularly wearing footwear with a constrictive toe-box during the fourth decade (adjusted OR 2.73 [95% CI 1.12, 6.67]). This risk factor was correlated in MZ (ρ = 0.38 [95% CI 0.15, 0.60]) but not DZ (ρ = -0.20 [95% CI -0.43, 0.03]) pairs. These correlations were significantly different (P = 0.002). Twins are correlated for HV, but we found no evidence that correlation was due to shared genetic factors. We identified an environmental risk factor, footwear with a constrictive toe-box, that is not shared to the same extent by MZ and DZ pairs, contrary to the assumption of the classic twin model. Footwear, and possibly genetic factors and unknown shared environmental factors, could contribute to developing HV. © 2016, American College of Rheumatology.

  6. Homovanillic acid in cerebrospinal fluid of 1388 children with neurological disorders.

    PubMed

    Molero-Luis, Marta; Serrano, Mercedes; Ormazábal, Aida; Pérez-Dueñas, Belén; García-Cazorla, Angels; Pons, Roser; Artuch, Rafael

    2013-06-01

    To determine the prevalence of dopaminergic abnormalities in 1388 children with neurological disorders, and to analyse their clinical, neuroradiological, and electrophysiological characteristics. We studied biogenic amines in 1388 cerebrospinal fluid (CSF) samples from children with neurological disorders (mean age 3y 10mo, SD 4y 5mo; 712 males, 676 females. Correlations among CSF homovanillic acid (HVA) values and other biochemical, clinical, neuroradiological, and electrophysiological parameters were analysed. Twenty-one patients with primary dopaminergic deficiencies were identified. Of the whole sample, 20% showed altered HVA. We report neurological diseases with abnormal CSF HVA values such as pontocerebellar hypoplasia, perinatal asphyxia, central nervous system infections, mitochondrial disorders, and other genetic diseases. Overlapping HVA levels between primary and secondary dopamine deficiencies were observed. Prevalence of low CSF HVA levels was significantly higher in neonatal patients (χ(2) =84.8, p<0.001). Abnormalities in white matter were associated with low CSF HVA (odds ratio 2.3, 95% confidence interval 1.5-3.5). HVA abnormalities are observed in various neurological diseases, but some are probably an unspecific finding. No clear limits for CSF HVA values pointing towards primary diseases can be stated. We report several neurological diseases showing HVA alterations. No neuroimaging traits were associated with low HVA values, except for white matter abnormalities. © The Authors. Developmental Medicine & Child Neurology © 2013 Mac Keith Press.

  7. Discrepancy of alignment in different weight bearing conditions before and after high tibial osteotomy.

    PubMed

    Wang, Joon Ho; Shin, Jung Min; Kim, Hyun Ho; Kang, Seung-Hoon; Lee, Byung Hoon

    2017-01-01

    To evaluate the differences in the amount of varus malalignment and valgus (over) correction in relation to three different weight bearing conditions from whole leg AP radiographs (single-limb (SL) stance, double-limb (DL) stance, supine position (S)) before and after high tibial osteotomy (HTO), and to evaluate which alignment parameters affect the changes for patients in three different weight bearing conditions. A total of 40 consecutive patients (43 knees) with varus osteoarthritis underwent navigation assisted open wedge HTO. Mechanical axis angle (MA) was measured before and after surgery from hip-to-ankle radiographs taken with patients in three different weight bearing conditions. To find significant factors that affect the alignment differences, several variables including patient demographics, soft tissue laxity, pelvic obliquity, and ground mechanical axis deviation of tibia (calculated by the angle between two lines, tibial anatomical axis and weight-bearing line) were evaluated. Pre-operatively, mean MA measured on SL stance radiographs was significantly more varus than on DL stance (10.1° ± 2.4° and 8.0° ± 2.6°, respectively, p < 0.001), which was significantly more varus than on supine position (6.6° ± 2.6°, p < 0.001). Meanwhile, in patients with post-operatively valgus corrected knee, MA did not show the same pattern of change as with pre-operative varus knee. Mean MA measured on DL stance radiographs was more valgus than in supine position (-3.0 o  ± 2.4 o and -2.6 o  ± 3.1 o , p = 0.455), while mean MA on SL stance radiographs (-2.0 o  ± 2.1 o ) was significantly less valgus than on DL stance (p = 0.002). The ground mechanical axis deviation of tibia showed a significant correlation with MA difference between SL and DL stance radiographs before (β = -0.341, p = 0.045) and after surgery (β = -0.536, p = 0.001). In pre-operative varus knee, the mean MA on SL stance was changed to

  8. Plasma homovanillic acid correlates inversely with history of childhood trauma in personality disordered and healthy control adults.

    PubMed

    Lee, Royce; Coccaro, Emil F

    2010-11-01

    Studies of the cerebrospinal fluid (CSF) level of the dopamine metabolite, homovanillic acid (HVA), suggest a relationship between CSF HVA concentration and history of childhood trauma. In this study, the authors test the hypothesis that this relationship is also present using peripheral levels of HVA in healthy volunteers and in personality disordered subjects. 68 personality disordered (PD) and healthy control (HC) subjects were chosen, in whom morning basal plasma HVA (pHVA) concentrations and an assessment of childhood trauma were obtained. History of childhood trauma was assessed using the Childhood Trauma Questionnaire (CTQ). A significant inverse correlation was found between CTQ Total scores and pHVA concentration across all subjects. In addition, pHVA was lower, and CTQ scores were higher, in PD as compared with HC subjects. Correlations with other personality and behavioral measures were not statistically significant. The data suggest that pHVA concentrations are inversely correlated with history of childhood trauma and that variability in this index of dopamine function may be affected by the history of childhood trauma in healthy and personality disordered subjects.

  9. The effects of diet and physical activity on plasma homovanillic acid in normal human subjects.

    PubMed

    Kendler, K S; Mohs, R C; Davis, K L

    1983-03-01

    This study examines the effect of diet and moderate physical activity on plasma levels of the dopamine metabolite homovanillic acid (HVA) in healthy young males. At weekly intervals, subjects were fed four isocaloric meals: polycose (pure carbohydrate), sustecal, low monoamine, and high monoamine. Moderate physical activity consisted of 30 minutes of exercise on a bicycle ergometer. The effect of diet on plasma HVA (pHVA) was highly significant. Compared to the polycose meal, the high monoamine meal significantly increased pHVA. Moderate physical activity also significantly increased pHVA. Future clinical studies using pHVA in man as an index of brain dopamine function should control for the effects of both diet and physical activity.

  10. Biodegradable magnesium-based screw clinically equivalent to titanium screw in hallux valgus surgery: short term results of the first prospective, randomized, controlled clinical pilot study

    PubMed Central

    2013-01-01

    Purpose Nondegradable steel-and titanium-based implants are commonly used in orthopedic surgery. Although they provide maximal stability, they are also associated with interference on imaging modalities, may induce stress shielding, and additional explantation procedures may be necessary. Alternatively, degradable polymer implants are mechanically weaker and induce foreign body reactions. Degradable magnesium-based stents are currently being investigated in clinical trials for use in cardiovascular medicine. The magnesium alloy MgYREZr demonstrates good biocompatibility and osteoconductive properties. The aim of this prospective, randomized, clinical pilot trial was to determine if magnesium-based MgYREZr screws are equivalent to standard titanium screws for fixation during chevron osteotomy in patients with a mild hallux valgus. Methods Patients (n=26) were randomly assigned to undergo osteosynthesis using either titanium or degradable magnesium-based implants of the same design. The 6 month follow-up period included clinical, laboratory, and radiographic assessments. Results No significant differences were found in terms of the American Orthopaedic Foot and Ankle Society (AOFAS) score for hallux, visual analog scale for pain assessment, or range of motion (ROM) of the first metatarsophalangeal joint (MTPJ). No foreign body reactions, osteolysis, or systemic inflammatory reactions were detected. The groups were not significantly different in terms of radiographic or laboratory results. Conclusion The radiographic and clinical results of this prospective controlled study demonstrate that degradable magnesium-based screws are equivalent to titanium screws for the treatment of mild hallux valgus deformities. PMID:23819489

  11. Plasma debrisoquin levels in the assessment of reduction of plasma homovanillic acid. The debrisoquin method.

    PubMed

    Riddle, M A; Jatlow, P I; Anderson, G M; Cho, S C; Hardin, M T; Cohen, D J; Leckman, J F

    1989-06-01

    Plasma concentrations of unconjugated homovanillic acid (pHVA) reflect both central nervous system (CNS) and peripheral dopamine metabolism. Debrisoquin sulfate (DBQ) blocks peripheral, but not CNS, production of HVA from dopamine. Administration of DBQ has been used to decrease the proportion of peripherally produced HVA in pHVA measurements, making such measurements more reflective of CNS turnover of dopamine. We studied the relationships between DBQ dose, plasma DBQ (pDBQ) levels, and changes in pHVA in a group of 21 subjects (9 normal controls and 12 with Tourette's syndrome). DBQ dose was moderately correlated with pDBQ levels (r = 0.63, p = 0.002). Subjects (n = 8) with mean pDBQ levels above 60 ng/ml had a 48% to 66% decrease in mean pHVA levels; this may reflect nearly complete inhibition of peripheral HVA production. Subjects (n = 13) with mean pDBQ levels below 55 ng/ml had decreases in pHVA levels from 10% to 58%. No debrisoquin was detected in cerebrospinal fluid samples. These data suggest that pDBQ levels above 60 ng/ml are sufficient to assure substantial inhibition of peripheral HVA production and that monitoring pDBQ levels may be useful when employing this method for studying CNS metabolism.

  12. Apparent contact angle and contact angle hysteresis on liquid infused surfaces.

    PubMed

    Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim

    2016-12-21

    We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small but finite ridge, which corresponds to an effective line tension term. We also predict contact angle hysteresis on liquid infused surfaces generated by the pinning of the contact lines by the surface corrugations. Our analytical expressions for both the apparent contact angle and contact angle hysteresis can be interpreted as 'weighted sums' between the contact angles of the infusing liquid relative to the droplet and surrounding gas phases, where the weighting coefficients are given by ratios of the fluid surface tensions.

  13. Effect of mental stress on plasma homovanillic acid in healthy human subjects.

    PubMed

    Sumiyoshi, T; Yotsutsuji, T; Kurachi, M; Itoh, H; Kurokawa, K; Saitoh, O

    1998-07-01

    Plasma levels of homovanillic acid (pHVA) have been suggested to provide a measure of dopaminergic activity in the central nervous system. The present study investigated the effect of mental stress by the Kraepelin test, a test of continuous arithmetic addition of single-digit figures for 30 min, on pHVA levels in 13 male psychiatrically normal healthy volunteers. Following an overnight fast and restricted physical activity, plasma samples were collected immediately before and after the administration of the Kraepelin test. Plasma HVA levels following the administration of the Kraepelin test were significantly lower than the pretest pHVA levels. The percent change in pHVA levels by the Kraepelin test positively correlated with pretest pHVA levels. The observed reduction in pHVA levels by mental stress in normal subjects may reflect some aspects of a dopamine-dependent restitutive system in the brain.

  14. Ankle joint pressure changes in a pes cavovarus model: supramalleolar valgus osteotomy versus lateralizing calcaneal osteotomy.

    PubMed

    Schmid, Timo; Zurbriggen, Sebastian; Zderic, Ivan; Gueorguiev, Boyko; Weber, Martin; Krause, Fabian G

    2013-09-01

    A fixed cavovarus foot deformity can be associated with anteromedial ankle arthrosis due to elevated medial joint contact stresses. Supramalleolar valgus osteotomies (SMOT) and lateralizing calcaneal osteotomies (LCOT) are commonly used to treat symptoms by redistributing joint contact forces. In a cavovarus model, the effects of SMOT and LCOT on the lateralization of the center of force (COF) and reduction of the peak pressure in the ankle joint were compared. A previously published cavovarus model with fixed hindfoot varus was simulated in 10 cadaver specimens. Closing wedge supramalleolar valgus osteotomies 3 cm above the ankle joint level (6 and 11 degrees) and lateral sliding calcaneal osteotomies (5 and 10 mm displacement) were analyzed at 300 N axial static load (half body weight). The COF migration and peak pressure decrease in the ankle were recorded using high-resolution TekScan pressure sensors. A significant lateral COF shift was observed for each osteotomy: 2.1 mm for the 6 degrees (P = .014) and 2.3 mm for the 11 degrees SMOT (P = .010). The 5 mm LCOT led to a lateral shift of 2.0 mm (P = .042) and the 10 mm LCOT to a shift of 3.0 mm (P = .006). Comparing the different osteotomies among themselves no significant differences were recorded. No significant anteroposterior COF shift was seen. A significant peak pressure reduction was recorded for each osteotomy: The SMOT led to a reduction of 29% (P = .033) for the 6 degrees and 47% (P = .003) for the 11 degrees osteotomy, and the LCOT to a reduction of 41% (P = .003) for the 5 mm and 49% (P = .002) for the 10 mm osteotomy. Similar to the COF lateralization no significant differences between the osteotomies were seen. LCOT and SMOT significantly reduced anteromedial ankle joint contact stresses in this cavovarus model. The unloading effects of both osteotomies were equivalent. More correction did not lead to significantly more lateralization of the COF or more reduction of peak pressure but a trend was

  15. Automated analysis of angle closure from anterior chamber angle images.

    PubMed

    Baskaran, Mani; Cheng, Jun; Perera, Shamira A; Tun, Tin A; Liu, Jiang; Aung, Tin

    2014-10-21

    To evaluate a novel software capable of automatically grading angle closure on EyeCam angle images in comparison with manual grading of images, with gonioscopy as the reference standard. In this hospital-based, prospective study, subjects underwent gonioscopy by a single observer, and EyeCam imaging by a different operator. The anterior chamber angle in a quadrant was classified as closed if the posterior trabecular meshwork could not be seen. An eye was classified as having angle closure if there were two or more quadrants of closure. Automated grading of the angle images was performed using customized software. Agreement between the methods was ascertained by κ statistic and comparison of area under receiver operating characteristic curves (AUC). One hundred forty subjects (140 eyes) were included, most of whom were Chinese (102/140, 72.9%) and women (72/140, 51.5%). Angle closure was detected in 61 eyes (43.6%) with gonioscopy in comparison with 59 eyes (42.1%, P = 0.73) using manual grading, and 67 eyes (47.9%, P = 0.24) with automated grading of EyeCam images. The agreement for angle closure diagnosis between gonioscopy and both manual (κ = 0.88; 95% confidence interval [CI), 0.81-0.96) and automated grading of EyeCam images was good (κ = 0.74; 95% CI, 0.63-0.85). The AUC for detecting eyes with gonioscopic angle closure was comparable for manual and automated grading (AUC 0.974 vs. 0.954, P = 0.31) of EyeCam images. Customized software for automated grading of EyeCam angle images was found to have good agreement with gonioscopy. Human observation of the EyeCam images may still be needed to avoid gross misclassification, especially in eyes with extensive angle closure. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  16. GABA and homovanillic acid in the plasma of Schizophrenic and bipolar I patients.

    PubMed

    Arrúe, Aurora; Dávila, Ricardo; Zumárraga, Mercedes; Basterreche, Nieves; González-Torres, Miguel A; Goienetxea, Biotza; Zamalloa, Maria I; Anguiano, Juan B; Guimón, José

    2010-02-01

    We have determined the plasma (p) concentration of gamma-aminobutyric acid (GABA) and the dopamine metabolite homovanillic acid (HVA), and the pHVA/pGABA ratio in schizophrenic and bipolar patients. The research was undertaken in a geographic area with an ethnically homogeneous population. The HVA plasma concentrations were significantly elevated in the schizophrenic patients compared to the bipolar patients. The levels of pGABA was significantly lower in the two groups of patients compared to the control group, while the pHVA/pGABA ratio was significantly greater in the both groups of patients compared to the controls. As the levels of pHVA and pGABA are partially under genetic control it is better to compare their concentrations within an homogeneous population. The values of the ratio pHVA/pGABA are compatible with the idea of an abnormal dopamine-GABA interaction in schizophrenic and bipolar patients. The pHVA/pGABA ratio may be a good peripheral marker in psychiatric research.

  17. Plasma homovanillic acid and treatment response in a large group of schizophrenic patients.

    PubMed

    Chang, W H; Hwu, H G; Chen, T Y; Lin, S K; Lung, F W; Chen, H; Lin, W L; Hu, W H; Lin, H N; Chien, C P

    1993-10-01

    Plasma levels of homovanillic acid (pHVA), a metabolite of dopamine, were measured in ninety-five Chinese schizophrenic patients free of neuroleptics for at least four weeks. These patients were treated with classical antipsychotics for six weeks. Pretreatment pHVA was positively correlated with the subsequent clinical response (r = 0.408, p < 0.0001). Good responders (BPRS improvement > or = 50%, n = 47) had higher pretreatment pHVA levels than poor responders (BPRS improvement < 50%, n = 48) (15.7 +/- 8.4 ng/ml versus 9.9 +/- 3.7 ng/ml, p < 0.0001). A higher than 15 ng/ml pretreatment pHVA level was associated with a more consistent clinical response to the subsequent treatment. Using a pHVA level of 12 ng/ml as a demarcation point, 72% of patients (34 of 47) who had pHVA > or = 12 responded whereas 65% (31 of 48) who had < 12 did not respond (chi-square = 13.02, p < 0.0001). These results suggest that higher pretreatment pHVA levels may predict a better clinical response to antipsychotics. Based upon the pHVA findings, two hypothetical subtypes of schizophrenia are proposed.

  18. Effects of toe-in and toe-in with wider step width on level walking knee biomechanics in varus, valgus, and neutral knee alignments.

    PubMed

    Bennett, Hunter J; Shen, Guangping; Cates, Harold E; Zhang, Songning

    2017-12-01

    Increased peak external knee adduction moments exist for individuals with knee osteoarthritis and varus knee alignments, compared to healthy and neutrally aligned counterparts. Walking with increased toe-in or increased step width have been individually utilized to successfully reduce 1st and 2nd peak knee adduction moments, respectfully, but have not previously been combined or tested among all alignment groups. The purpose of this study was to compare toe-in only and toe-in with wider step width gait modifications in individuals with neutral, valgus, and varus alignments. Thirty-eight healthy participants with confirmed varus, neutral, or valgus frontal-plane knee alignment through anteroposterior radiographs, performed level walking in normal, toe-in, and toe-in with wider step width gaits. A 3×3 (group×intervention) mixed model repeated measures ANOVA compared alignment groups and gait interventions (p<0.05). The 1st peak knee adduction moment was reduced in both toe-in and toe-in with wider step width compared to normal gait. The 2nd peak adduction moment was increased in toe-in compared to normal and toe-in with wider step width. The adduction impulse was also reduced in toe-in and toe-in with wider step width compared to normal gait. Peak knee flexion and external rotation moments were increased in toe-in and toe-in with wider step width compared to normal gait. Although the toe-in with wider step width gait seems to be a viable option to reduce peak adduction moments for varus alignments, sagittal, and transverse knee loadings should be monitored when implementing this gait modification strategy. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Role of Fixation and Postoperative Regimens in the Long-Term Outcomes of Distal Chevron Osteotomy: A Randomized Controlled Two-by-Two Factorial Trial of 100 Patients.

    PubMed

    Pentikäinen, Ilkka; Piippo, Jouni; Ohtonen, Pasi; Junila, Juhani; Leppilahti, Juhana

    2015-01-01

    The necessity of chevron osteotomy fixation is controversial and evidence for the effectiveness of postoperative regimens is limited. In a prospective, randomized study, we compared the long-term results of 2 operative techniques (osteotomy fixation versus no fixation) and 2 postoperative regimens (a soft cast versus an elastic bandage) in 100 patients who underwent surgery for hallux valgus. Clinical evaluations with the American Orthopaedic Foot and Ankle Society (AOFAS) scale scoring were performed at baseline and 6 weeks, 6 months, 1 year, and a mean of 7.9 years postoperatively. The mean AOFAS function score were better in the group treated without osteotomy fixation and with an elastic bandage at 6 weeks postoperatively, but the differences then disappeared. The total AOFAS scores improved significantly in all 4 subgroups during the first 12 months; however, in the long term, some deterioration occurred. In the AOFAS scores, the average function, alignment, and total points were significantly worse when the preoperative hallux valgus angles exceeded 30°. The incidence of complication was low (1%); there was 1 superficial wound infection. The AOFAS score did not differ statistically among the groups in our population. An elastic bandage for postoperative treatment is recommended. The risk of recurrence is greater and functional result worse if the preoperative hallux valgus angle exceeds 30°. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Cartilage loss patterns within femorotibial contact regions during deep knee bend.

    PubMed

    Michael Johnson, J; Mahfouz, Mohamed R

    2016-06-14

    Osteoarthritis (OA) can alter knee kinematics and stresses. The relationship between cartilage loss in OA and kinematics is unclear, with existing work focusing on static wear and morphology. In this work, femorotibial cartilage maps were coupled with kinematics to investigate the relationship between kinematics and cartilage loss, allowing for more precise treatment and intervention. Cartilage thickness maps were created from healthy and OA subgroups (varus, valgus, and neutral) and mapped to a statistical bone atlas. Video fluoroscopy determined contact regions from 0° to 120° flexion. Varus and valgus subgroups displayed different wear patterns across the range of flexion, with varus knees showing more loss in early flexion and valgus in deeper flexion. For the femur, varus knees had more wear in the medial compartment than neutral or valgus and most wear at both 0° and 20° flexion. In the lateral femoral compartment, the valgus subgroup showed significantly more wear from 20° to 60° flexion as compared to other angles, though varus knees displayed highest magnitude of wear. For the tibia, most medial wear occurred at 0-40° flexion and most lateral occurred after 60° flexion. Knowing more about cartilage changes in OA knees provides insight as to expected wear or stresses on implanted components after arthroplasty. Combining cartilage loss patterns with kinematics allows for pre-surgical intervention and treatments tailored to the patient׳s alignment and kinematics. Reported wear patterns may also serve as a gauge for post-operative loading to be considered when placing implant components. Copyright © 2016. Published by Elsevier Ltd.

  1. Development and validation of self-reported line drawings for assessment of knee malalignment and foot rotation: a cross-sectional comparative study

    PubMed Central

    2010-01-01

    Background For large scale epidemiological studies clinical assessments and radiographs can be impractical and expensive to apply to more than just a sample of the population examined. The study objectives were to develop and validate two novel instruments for self-reported knee malalignment and foot rotation suitable for use in questionnaire studies of knee pain and osteoarthritis. Methods Two sets of line drawings were developed using similar methodology. Each instrument consisted of an explanatory question followed by a set of drawings showing straight alignment, then two each at 7.5° angulation and 15° angulation in the varus/valgus (knee) and inward/outward (foot) directions. Forty one participants undertaking a community study completed the instruments on two occasions. Participants were assessed once by a blinded expert clinical observer with demonstrated excellent reproducibility. Validity was assessed by sensitivity, specificity and likelihood ratio (LR) using the observer as the reference standard. Reliability was assessed using weighted kappa (κ). Knee malalignment was measured on 400 knee radiographs. General linear model was used to assess for the presence of a linear increase in knee alignment angle (measured medially) from self-reported severe varus to mild varus, straight, mild valgus and severe valgus deformity. Results Observer reproducibility (κ) was 0.89 and 0.81 for the knee malalignment and foot rotation instruments respectively. Self-reported participant reproducibility was also good for the knee (κ 0.73) and foot (κ 0.87) instruments. Validity was excellent for the knee malalignment instrument, with a sensitivity of 0.74 (95%CI 0.54, 0.93) and specificity of 0.97 (95%CI 0.94, 1.00). Similarly the foot rotation instrument was also found to have high sensitivity (0.92, 95%CI 0.83, 1.01) and specificity (0.96, 95%CI 0.93, 1.00). The knee alignment angle increased progressively from self reported severe varus to mild varus, straight, mild

  2. Ultrasound evaluation of intrinsic plantar muscles and fascia in hallux valgus

    PubMed Central

    Lobo, César Calvo; Marín, Alejandro Garrido; Sanz, David Rodríguez; López, Daniel López; López, Patricia Palomo; Morales, Carlos Romero; Corbalán, Irene Sanz

    2016-01-01

    Abstract A cross-sectional area (CSA) and thickness reduction of the abductor hallucis (AbH) is shown in subjects with hallux valgus (HV). To date, other soft-tissue structures have not been researched in relation with HV. The aim of this study was to compare the CSA and thickness of the intrinsic plantar muscles and fascia (PF) between feet with and without HV. Therefore, a cross-sectional and case-control study was performed using B-mode with an iU22 Philips ultrasound system and a 5 to 17-MHz transducer. The CSA and thickness were measured for the AbH, flexor digitorum brevis (FDB) and flexor hallucis brevis (FHB), and also the thickness for the anterior, middle, and posterior PF portions. A convenience sample of 40 feet, 20 with HV and 20 without HV, was recruited from a clinical and research center. A multivariate regression analysis using linear regression was performed to evaluate the ultrasound imaging measurements (α = 0.05). Consequently, statistically significant differences were observed between the groups (P < 0.05) for the AbH and FHB thickness, and CSA reduction, and also the plantar fascia thickness increase in favor of the HV group. On the contrary, the FDB thickness and CSA did not show statistically significant differences (P ≥ 0.05). In conclusion, the CSA and thickness of the AbH and FHB intrinsic plantar muscles are reduced, whereas the thickness of the anterior, middle, and posterior PF portions are increased, in subjects with HV compared with those without HV. PMID:27828846

  3. Boomerang proximal tibial osteotomy for the treatment of severe varus gonarthrosis.

    PubMed

    Sangkaew, Chanchit; Piyapittayanun, Peerapong

    2013-06-01

    The purpose of the study was to review the results of modified infratubercle displacement osteotomy in patients with severe varus gonarthrosis and to determine the factors influencing outcomes. A total of 177 knees in 133 patients with severe varus gonarthrosis were treated with infratubercle boomerang-shaped osteotomy, stabilised with dual plates. The mean age of the patients was 63.8 years (range 43-80 years), and the mean follow-up period was 61.4 months (range 24 -139 months). The factors associated with clinical and survival outcomes were analysed including age, gender, body mass index (BMI), preoperative and post-operative femorotibial angle and femorotibial angle at one year after surgery. Using the Knee Society clinical rating system 149 knees or 84.2 % were rated as having good to excellent results and 21 knees or 15.8 % as having fair to poor results. Overall, the mean preoperative knee score of 33.6 points had improved significantly to 80.7 points at the final follow-up (p < 0.001). Using Kaplan-Meier survivorship analysis the five-year survival was 97.1 % with conversion to arthroplasty or second osteotomy as the end point and 89.2 % with a knee score of under 70 points as the end point. The anatomical femorotibial angle at one year after osteotomy had the most significant positive effect on the clinical (p < 0.001) and survival outcomes for all end points (p = 0.002 for conversion to arthroplasty or second osteotomy and p < 0.001 for knee score less than 70 points). The boomerang osteotomy can create adequate valgus alignment in severe varus gonarthrosis. The one-year post-operative knee alignment of 11° valgus provided the most satisfactory results and that between six and 15° valgus the longest survival time.

  4. Optimal reconstruction angles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cook, G.O. Jr.; Knight, L.

    1979-07-01

    The question of optimal projection angles has recently become of interest in the field of reconstruction from projections. Here, studies are concentrated on the n x n pixel space, where literative algorithms such as ART and direct matrix techniques due to Katz are considered. The best angles are determined in a Gauss--Markov statistical sense as well as with respect to a function-theoretical error bound. The possibility of making photon intensity a function of angle is also examined. Finally, the best angles to use in an ART-like algorithm are studied. A certain set of unequally spaced angles was found to bemore » preferred in several contexts. 15 figures, 6 tables.« less

  5. Is head-shaft angle a valuable continuous risk factor for hip migration in cerebral palsy?

    PubMed

    Chougule, Sanjay; Dabis, John; Petrie, Aviva; Daly, Karen; Gelfer, Yael

    2016-12-01

    Reimer's migration percentage (MP) is the most established radiographic risk factor for hip migration in cerebral palsy (CP), and it assists surgical decision-making. The head-shaft angle (HSA) measures the valgus of the head and neck in relation to the shaft and may also be a useful predictor of hip migration at a young age. This study first defined normal values and investigated whether the head-shaft angle (HSA) is a continuous risk factor for hip migration in CP. Three hundred and fifty AP pelvic radiographs of 100 consecutive children comprising the hip surveillance programme in our region were analysed for MP and HSA. Inclusion criteria were children with spastic CP and Gross Motor Function Classification System (GMFCS) levels of III-V, along with a minimum follow-up of 5 years. The mean age was 8.8 (range 3-18) years and the mean follow-up time was 7.5 (range 5-10) years. Radiographs of 103 typically developing children (TDC) were selected for the control group. The reliability of the measurements was determined. A random effects analysis was used to assess the relationship between MP and HSA for all data and for MP > 40 %. The TDC cohort had a mean HSA of 157.7° whilst that for the CP cohort was 161.7°. The value declined with age in both groups but remained consistently higher in the CP group. A random effects analysis considering the longitudinal data showed that there was no significant effect of HSA on MP. Similarly, when excluding CP patients with MP < 40 %, there was no significant effect of HSA on MP. This study found no correlation between HSA and hip migration in children with CP in this age group. Using the HSA as a routine radiographic measure in the management pathway across childhood does not offer any added value. Early enrolment onto the hip surveillance programme could offer a better prediction of hip migration using the HSA at a very young age. II retrospective prognostic study.

  6. The Thrower's Elbow: Arthroscopic Treatment of Valgus Extension Overload Syndrome

    PubMed Central

    Altchek, David W.

    2006-01-01

    Injury to the medial collateral ligament of the elbow (MCL) can be a career-threatening injury for an overhead athlete without appropriate diagnosis and treatment. It has been considered separately from other athletic injuries due to the unique constellation of pathology that results from repetitive overhead throwing. The past decade has witnessed tremendous gains in understanding of the complex interplay between the dynamic and static stabilizers of the athlete's elbow. Likewise, the necessity to treat these problems in a minimally invasive manner has driven the development of sophisticated techniques and instrumentation for elbow arthroscopy. MCL injuries, ulnar neuritis, valgus extension overload with osteophyte formation and posteromedial impingement, flexor pronator strain, medial epicondyle pathology, and osteochondritis dissecans (OCD) of the capitellum have all been described as sequelae of the overhead throwing motion. In addition, loose body formation, bony spur formation, and capsular contracture can all be present in conjunction with these problems or as isolated entities. Not all pathology in the thrower's elbow is amenable to arthroscopic treatment; however, the clinician must be familiar with all of these problems in order to form a comprehensive differential diagnosis for an athlete presenting with elbow pain, and he or she must be comfortable with the variety of open and arthroscopic treatments available to best serve the patient. An understanding of the anatomy and biomechanics of the thrower's elbow is critical to the care of this population. The preoperative evaluation should focus on a thorough history and physical examination, as wellas on specific diagnostic imaging modalities. Arthroscopic setup, including anesthesia, patient positioning, and portal choices will be discussed. Operative techniques in the anterior and posterior compartments will bereviewed, as well as postoperative rehabilitationandsurgical results. Lastly, complications will

  7. Porous Titanium Wedges in Lateral Column Lengthening for Adult-Acquired Flatfoot Deformity.

    PubMed

    Moore, Spencer H; Carstensen, S Evan; Burrus, M Tyrrell; Cooper, Truitt; Park, Joseph S; Perumal, Venkat

    2017-10-01

    Lateral column lengthening (LCL) is a common procedure for reconstruction of stage II flexible adult-acquired flatfoot deformity (AAFD). The recent development of porous titanium wedges for this procedure provides an alternative to allograft and autograft. The purpose of this study was to report radiographic and clinical outcomes achieved with porous titanium wedges in LCL. A retrospective analysis of 34 feet in 30 patients with AAFD that received porous titanium wedges for LCL from January 2011 to October 2014. Deformity correction was assessed using both radiographic and clinical parameters. Radiographic correction was assessed using the lateral talo-first metatarsal angle, the talonavicular uncoverage percentage, and the first metatarsocuneiform height. The hindfoot valgus angle was measured. Patients were followed from a minimum of 6 months up to 4 years (mean 16.1 months). Postoperative radiographs demonstrated significant correction in all 3 radiographic criteria and the hindfoot valgus angle. We had no cases of nonunion, no wedge migration, and no wedges have been removed to date. The most common complication was calcaneocuboid joint pain (14.7%). Porous titanium wedges in LCL can achieve good radiographic and clinical correction of AAFD with a low rate of nonunion and other complications. Level IV: Case series.

  8. {l_angle}110{r_angle} dendrite growth in aluminum feathery grains

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Henry, S.; Rappaz, M.; Jarry, P.

    1998-11-01

    Automatic indexing of electron backscattered diffraction patterns, scanning electron microscopy, and optical microscopy observations have been carried out on aluminum-magnesium-silicon, aluminum-copper, and aluminum-silicon alloys directionally solidified or semicontinuously cast using the direct chill casting process. From these combined observations, it is shown that the feathery grains are made of {l_angle}110{r_angle} primary dendrite trunks (e.g., [011{bar 1}]) split in their centers by a coherent (111) twin plane. The average spacing of the dendrite trunks in the twin plane (about 10 to 20 {micro}m) is typically one order of magnitude smaller than that separating successive rows of trunks (or twin planes). Themore » [011{bar 1}] orientation of these trunks is close to the thermal gradient direction (typically within 15 deg)--a feature probably resulting from a growth competition mechanism similar to that occurring during normal <100> columnar dendrite growth. On both sides of these trunks, secondary dendrite arms also grow along {l_angle}110{r_angle} directions. Their impingement creates wavy noncoherent twin boundaries between the coherent twin planes. In the twin plane, evidence is shown that {l_angle}110{r_angle} branching mechanisms lead to the propagation of the twinned regions, to the regular arrangement of the primary dendrite trunks along a [{bar 2}11] direction, and to coherent planar twin boundaries. From these observations, it is concluded that the feathery grains are probably the result of a change from a normal <100> to a {l_angle}110{r_angle} surface tension/attachment kinetics anisotropy growth mode. Finally, the proposed mechanisms of leathery grain growth are further supported by the observation of {l_angle}110{r_angle} dendrite growth morphologies in thin aluminum-zinc coatings.« less

  9. Pretreatment plasma homovanillic acid in schizophrenia and schizoaffective disorder: the influence of demographic variables and the inpatient drug-free period.

    PubMed

    Sharma, R P; Javaid, J I; Davis, J M; Janicak, P G

    1998-09-15

    The relationship between plasma homovanillic acid (pHVA) and schizophrenic symptoms has not been conclusively determined. We reexamine pHVA levels in a new sample of patients with emphasis on demographic variables and the drug-free period. Plasma HVA levels were studied in 54 schizophrenic and schizoaffective-disordered, drug-free inpatients suffering from a psychotic exacerbation. A significant correlation was observed between pHVA levels and the number of inpatient drug-free days in the total sample, as well as the schizophrenic patient subsample. Further, pHVA was significantly and positively correlated with the duration of illness in the schizophrenic patient subsample. Plasma HVA correlations with behavior, as measured by Brief Psychiatric Rating Scale factors (anxiety/depression and hostility/suspiciousness), emerged only when considering schizophrenic patients drug-free for more than 2 weeks. No correlation was found between pHVA and the age of illness onset or the duration of the delay of treatment of the first psychotic episode. The effects of antipsychotic withdrawal on levels of pHVA in clinical populations may have to be examined and controlled for in future studies attempting to study the relationship between this metabolite and behavior in acutely ill, drug-free schizophrenic patients.

  10. Plasma homovanillic acid in the prodromal phase of schizophrenia.

    PubMed

    Sumiyoshi, T; Kurachi, M; Kurokawa, K; Yotsutsuji, T; Uehara, T; Itoh, H; Saitoh, O

    2000-03-01

    Plasma levels of homovanillic acid (pHVA) have been used as a peripheral measure of central dopaminergic activity. Despite a large body of studies investigating pHVA in schizophrenia, little is known about pHVA in patients in the prodromal phase of the illness. Plasma HVA levels of 12 male outpatients meeting DSM-III-R criteria for the prodromal phase of schizophrenia at the time of blood sampling (who later developed psychotic symptoms) were compared with those of 12 normal male healthy volunteers. Task amounts in the Kraepelin arithmetic test at the time of blood sampling were compared between the prodromal patients and normal controls and were correlated with pHVA levels. The prodromal patients had significantly higher pHVA levels compared with normal control subjects. The mean amount of the arithmetic task for the prodromal patients was significantly less than that for controls. In the patient group, a significant negative correlation was observed between pHVA levels and the task amounts. Data from the present study indicate the presence of dopaminergic dysfunction in the prodromal stage of schizophrenia that is associated with neuropsychological impairment. Increased pHVA levels in the prodromal patients may have implications for early detection of schizophrenia.

  11. Low serum concentrations of vitamin B6 and iron are related to panic attack and hyperventilation attack.

    PubMed

    Mikawa, Yasuhito; Mizobuchi, Satoshi; Egi, Moritoki; Morita, Kiyoshi

    2013-01-01

    Patients undergoing a panic attack (PA) or a hyperventilation attack (HVA) are sometimes admitted to emergency departments (EDs). Reduced serotonin level is known as one of the causes of PA and HVA. Serotonin is synthesized from tryptophan. For the synthesis of serotonin, vitamin B6 (Vit B6) and iron play important roles as cofactors. To clarify the pathophysiology of PA and HVA, we investigated the serum levels of vitamins B2, B6, and B12 and iron in patients with PA or HVA attending an ED. We measured each parameter in 21 PA or HVA patients and compared the values with those from 20 volunteers. We found that both Vit B6 and iron levels were significantly lower in the PA/HVA group than in the volunteer group. There was no significant difference in the serum levels of vitamins B2 or B12. These results suggest that low serum concentrations of Vit B6 and iron are involved in PA and HVA. Further studies are needed to clarify the mechanisms involved in such differences.

  12. THE INFLUENCE OF HIP STRENGTH ON KNEE KINEMATICS DURING A SINGLE-LEGGED MEDIAL DROP LANDING AMONG COMPETITIVE COLLEGIATE BASKETBALL PLAYERS.

    PubMed

    Suzuki, Hidetomo; Omori, Go; Uematsu, Daisuke; Nishino, Katsutoshi; Endo, Naoto

    2015-10-01

    A smaller knee flexion angle and larger knee valgus angle during weight-bearing activities have been identified as risk factors for non-contact anterior cruciate ligament (ACL) injuries. To prevent such injuries, attention has been focused on the role of hip strength in knee motion control. However, gender differences in the relationship between hip strength and knee kinematics during weight-bearing activities in the frontal plane have not been evaluated. The purpose of this study was to determine the influence of hip strength on knee kinematics in both genders during a single-legged landing task in the frontal plane. The hypotheses were that 1) subjects with a greater hip strength would demonstrate larger knee flexion and smaller knee valgus and internal rotation angles and 2) no gender differences would exist during the single-legged landing task. Forty-three Japanese collegiate basketball players (20 males, 23 females) participated in this study. Three-dimensional motion analysis was used to evaluate knee kinematics during a single-legged medial drop landing (SML). A hand-held dynamometer was used to assess hip extensor (HEXT), abductor (HAB), and external rotator (in two positions: seated position [SHER] and prone [PHER]) isometric strength. Spearman rank correlation coefficients (ρ) were determined for correlations between hip strength and knee kinematics at initial contact (IC) and peak (PK) during SML (p < 0.05). Negative correlations were observed between the knee valgus angle at IC and HEXT (ρ = -0.48, p = 0.02), HAB (ρ = -0.46, p = 0.03) and PHER (ρ = -0.44, p = 0.04) strength in females. In addition, a significant positive correlation was observed between the knee flexion angle at PK and HEXT strength (ρ = 0.61, p = 0.004) in males. Significant correlations between hip strength and knee kinematics during SML were observed in both genders. Hip strength may, therefore, play an important role in knee motion control during sports activities

  13. Differences in lower extremity anatomical and postural characteristics in males and females between maturation groups.

    PubMed

    Shultz, Sandra J; Nguyen, Anh-Dung; Schmitz, Randy J

    2008-03-01

    Descriptive, cross-sectional. We compared lower extremity anatomical characteristics in males and females between different maturation groups. Sex differences have been observed in lower extremity anatomical characteristics. While the reasons contributing to these sex differences in adults are unknown, there is evidence that anatomy and posture change considerably during growth and development. One hundred seventy-three young athletes (age range, 9-18 years) were assessed for stage of maturation and placed into 1 of 3 groups, according to Tanners stages 1 and 2 (MatGrp1), 3 and 4 (MatGrp2), and 5 (MatGrp3). Participants were measured for pelvic angle, hip anteversion, quadriceps angle, tibiofemoral angle, femur length, tibial length, genu recurvatum, tibial torsion, navicular drop, general joint laxity, and anterior knee laxity. Data were compared by sex and maturation group. When comparing maturation groups, limb length, pelvic angle, and tibial torsion increased with maturation, and anterior knee laxity, genu recurvatum, tibiofemoral angle, and foot pronation decreased with maturation. Females had greater general joint laxity, hip anteversion, and tibiofemoral angles, and shorter femur and tibial lengths than males, regardless of maturation group. Maturational changes in knee laxity and quadriceps angles were sex dependent. We observed a general change of posture with maturation that began with greater knee valgus, knee recurvatum, and foot pronation in MatGrp1, then moved toward a relative straightening and external rotation of the knee, and supination of the foot in later maturation groups. While the majority of the measures changed similarly in males and females across maturation groups, decreases in quadriceps angles and anterior knee laxity were greater in males compared to females, and females were observed to have a more inwardly rotated hip and valgus knee posture, compared to males, particularly in later maturation groups.

  14. The Critical Angle Can Override the Brewster Angle

    ERIC Educational Resources Information Center

    Froehle, Peter H.

    2009-01-01

    As a culminating activity in their study of optics, my students investigate polarized light and the Brewster angle. In this exercise they encounter a situation in which it is impossible to measure the Brewster angle for light reflecting from a particular surface. This paper describes the activity and explains the students' observations.

  15. Traumeel S® for pain relief following hallux valgus surgery: a randomized controlled trial

    PubMed Central

    2010-01-01

    Background In spite of recent advances in post-operative pain relief, pain following orthopedic surgery remains an ongoing challenge for clinicians. We examined whether a well known and frequently prescribed homeopathic preparation could mitigate post-operative pain. Method We performed a randomized, double blind, placebo-controlled trial to evaluate the efficacy of the homeopathic preparation Traumeel S® in minimizing post-operative pain and analgesic consumption following surgical correction of hallux valgus. Eighty consecutive patients were randomized to receive either Traumeel tablets or an indistinguishable placebo, and took primary and rescue oral analgesics as needed. Maximum numerical pain scores at rest and consumption of oral analgesics were recorded on day of surgery and for 13 days following surgery. Results Traumeel was not found superior to placebo in minimizing pain or analgesic consumption over the 14 days of the trial, however a transient reduction in the daily maximum post-operative pain score favoring the Traumeel arm was observed on the day of surgery, a finding supported by a treatment-time interaction test (p = 0.04). Conclusions Traumeel was not superior to placebo in minimizing pain or analgesic consumption over the 14 days of the trial. A transient reduction in the daily maximum post-operative pain score on the day of surgery is of questionable clinical importance. Trial Registration This study was registered at ClinicalTrials.gov. # NCT00279513 PMID:20380750

  16. Undetected angle closure in patients with a diagnosis of open-angle glaucoma.

    PubMed

    Varma, Devesh K; Simpson, Sarah M; Rai, Amandeep S; Ahmed, Iqbal Ike K

    2017-08-01

    The aim of this study was to identify the proportion of patients referred to a tertiary glaucoma centre with a diagnosis of open-angle glaucoma (OAG) who were found to have angle closure glaucoma. Retrospective chart review. Consecutive new patients referred for glaucoma management to a tertiary centre between July 2010 and December 2011 were reviewed. Patients whose referrals for glaucoma assessment specified angle status as "open" were included. The data collected included glaucoma specialist's angle assessment, diagnosis, and glaucoma severity. The status of those with 180 degrees or more Shaffer angle grading of 0 was classified as "closed." From 1234 glaucoma referrals, 179 cases were specified to have a diagnosis of OAG or when angles were known to be open. Of these, 16 (8.9%) were found on examination by the glaucoma specialist to have angle closure. Pseudoexfoliation was present in 4 of 16 patients (25%) in the missed angle-closure glaucoma (ACG) group and 22 of 108 patients (13.5%) in the remaining OAG group. There was no difference found in demographic or ocular biometric parameters between those with confirmed OAG versus those with missed ACG. Almost 1 in 11 patients referred by ophthalmologists to a tertiary glaucoma centre with a diagnosis of OAG were in fact found to have angle closure. Given the different treatment approaches for ACG versus OAG, this study suggests a need to strengthen angle evaluations. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  17. Is it too early to move to full electronic PROM data collection?: A randomized controlled trial comparing PROM's after hallux valgus captured by e-mail, traditional mail and telephone.

    PubMed

    Palmen, Leonieke N; Schrier, Joost C M; Scholten, Ruben; Jansen, Justus H W; Koëter, Sander

    2016-03-01

    Patient reported outcome measures (PROM's) after hallux valgus surgery are used to rate the effectiveness as perceived by the patient. The interpretability of these PROM's is highly dependent on participation rate. Data capture method may be an important factor contributing to the response rate. We investigated the effect on response rate of traditional paper mail, telephone and e-mail PROM's after hallux valgus surgery. All consecutive patients operated between January and September 2013, were identified. Included patients were randomized by envelope in three groups: traditional pen and paper mail, e-mail and telephone. They were asked to fill in a FFI and EQ-5D. Two weeks later non-responders were sent a reminder. Of the 73 included patients, 25 were approached by mail, 24 by e-mail and 24 patients by telephone. The response rate on traditional mail was highest (88%), while response on e-mail was lowest (33%). Response rate on telephone was also high (79%). Response rate on traditional mail and telephone was significantly higher (p<0.001) than response on e-mail. Though electronic data collection has enormous potential, this study shows that e-mail yields unacceptable low response rates. It is too early to replace traditional pen-and-paper PROM's by electronic questionnaires. Copyright © 2015 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  18. Evaluation of blotchy pigments in the anterior chamber angle as a sign of angle closure

    PubMed Central

    Rao, Harsha L; Mungale, Sachin C; Kumbar, Tukaram; Parikh, Rajul S; Garudadri, Chandra S

    2012-01-01

    Background: Blotchy pigments in the anterior chamber (AC) angle are considered diagnostic of primary angle closure (PAC). But there are no reports either on the prevalence of blotchy pigments in AC angles or the validity of this sign. Aims: To determine the prevalence of blotchy pigments in AC angles and to evaluate their relationship with glaucomatous optic neuropathy (GON) in eyes with occludable angles. Setting and Design: Cross-sectional, comparative study. Materials and Methods: Gonioscopy was performed in 1001 eyes of 526 subjects (245 eyes of 148 consecutive, occludable angle subjects and 756 eyes of 378 non-consecutive, open angle subjects), above 35 years of age. Quadrant-wise location of blotchy pigments was documented. Statistical Analysis: Odds of blotchy pigments in occludable angles against that in open angles were evaluated. Relationship of GON with blotchy pigments in occludable angle eyes was evaluated using a multivariate model. Results: Prevalence of blotchy pigments in occludable angles was 28.6% (95% CI, 22.9-34.3) and in open angles was 4.7% (95% CI, 3.2-6.3). Blotchy pigments were more frequently seen in inferior (16%) and superior quadrants (15%) of occludable angles, and inferior quadrant of open angles (4%). Odds of superior quadrant blotchy pigments in occludable angles were 33 times that in open angles. GON was seen in 107 occludable angle eyes. Blotchy pigments were not significantly associated with GON (odds ratio = 0.5; P = 0.1). Conclusions: Blotchy pigments were seen in 28.6% of occludable angle eyes and 4.7% of open angles eyes. Presence of blotchy pigments in the superior quadrant is more common in occludable angles. Presence of GON in occludable angle eyes was not associated with blotchy pigments. PMID:23202393

  19. Biomechanical Effects of an Injury Prevention Program in Preadolescent Female Soccer Athletes.

    PubMed

    Thompson, Julie A; Tran, Andrew A; Gatewood, Corey T; Shultz, Rebecca; Silder, Amy; Delp, Scott L; Dragoo, Jason L

    2017-02-01

    Anterior cruciate ligament (ACL) injuries are common, and children as young as 10 years of age exhibit movement patterns associated with an ACL injury risk. Prevention programs have been shown to reduce injury rates, but the mechanisms behind these programs are largely unknown. Few studies have investigated biomechanical changes after injury prevention programs in children. Purpose/Hypothesis: To investigate the effects of the F-MARC 11+ injury prevention warm-up program on changes to biomechanical risk factors for an ACL injury in preadolescent female soccer players. We hypothesized that the primary ACL injury risk factor of peak knee valgus moment would improve after training. In addition, we explored other kinematic and kinetic variables associated with ACL injuries. Controlled laboratory study. A total of 51 female athletes aged 10 to 12 years were recruited from soccer clubs and were placed into an intervention group (n = 28; mean [±SD] age, 11.8 ± 0.8 years) and a control group (n = 23; mean age, 11.2 ± 0.6 years). The intervention group participated in 15 in-season sessions of the F-MARC 11+ program (2 times/wk). Pre- and postseason motion capture data were collected during preplanned cutting, unanticipated cutting, double-leg jump, and single-leg jump tasks. Lower extremity joint angles and moments were estimated using OpenSim, a biomechanical modeling system. Athletes in the intervention group reduced their peak knee valgus moment compared with the control group during the double-leg jump (mean [±standard error of the mean] pre- to posttest change, -0.57 ± 0.27 %BW×HT vs 0.25 ± 0.25 %BW×HT, respectively; P = .034). No significant differences in the change in peak knee valgus moment were found between the groups for any other activity; however, the intervention group displayed a significant pre- to posttest increase in peak knee valgus moment during unanticipated cutting ( P = .044). Additional analyses revealed an improvement in peak ankle eversion

  20. Control of exogenous factors affecting plasma homovanillic acid concentration.

    PubMed

    Davidson, M; Giordani, A B; Mohs, R C; Mykytyn, V V; Platt, S; Aryan, Z S; Davis, K L

    1987-04-01

    Measurements of plasma homovanillic acid (pHVA) concentrations appear to be a valid research strategy in psychiatric disorders in which a central dopamine (DA) abnormality has been implicated. This study provides guidance about the control of some of the exogenous factors affecting pHVA concentrations. Fasting for 14 hours eliminates the dietary effects on pHVA in healthy human subjects. Changing position, walking for 30 minutes, or smoking two cigarettes has no effect on pHVA concentrations.

  1. Serum tryptase concentrations in beekeepers with and without Hymenoptera venom allergy.

    PubMed

    Carballada, F; Alonso, M; Vizcaino, L; Coutinho, V; Núñez, R; Vidal, C; Boquete, M; González-Quintela, A

    2013-01-01

    Increased tryptase concentrations are a risk marker for the severity of reactions to Hymenoptera stings or venom immunotherapy To investigate serum tryptase concentrations in beekeepers with and without Hymenoptera venom allergy (HVA). Serum tryptase concentrations were measured in adult patients with HVA (n = 91, 37 of whom were beekeepers), beekeepers without HVA (n = 152), and control individuals from the general adult population (n = 246). Multivariate analyses revealed that serum tryptase levels were positively associated with beekeeping activities (P < .001) and HVA (P < .001). Tryptase levels were also positively associated with age (P < .001) and male'sex (P = .02), and negatively associated with alcoho consumption (P = .002). Beekeeping and HVA are independently associated with increased concentrations of serum tryptase.

  2. Investigations of interpolation errors of angle encoders for high precision angle metrology

    NASA Astrophysics Data System (ADS)

    Yandayan, Tanfer; Geckeler, Ralf D.; Just, Andreas; Krause, Michael; Asli Akgoz, S.; Aksulu, Murat; Grubert, Bernd; Watanabe, Tsukasa

    2018-06-01

    Interpolation errors at small angular scales are caused by the subdivision of the angular interval between adjacent grating lines into smaller intervals when radial gratings are used in angle encoders. They are often a major error source in precision angle metrology and better approaches for determining them at low levels of uncertainty are needed. Extensive investigations of interpolation errors of different angle encoders with various interpolators and interpolation schemes were carried out by adapting the shearing method to the calibration of autocollimators with angle encoders. The results of the laboratories with advanced angle metrology capabilities are presented which were acquired by the use of four different high precision angle encoders/interpolators/rotary tables. State of the art uncertainties down to 1 milliarcsec (5 nrad) were achieved for the determination of the interpolation errors using the shearing method which provides simultaneous access to the angle deviations of the autocollimator and of the angle encoder. Compared to the calibration and measurement capabilities (CMC) of the participants for autocollimators, the use of the shearing technique represents a substantial improvement in the uncertainty by a factor of up to 5 in addition to the precise determination of interpolation errors or their residuals (when compensated). A discussion of the results is carried out in conjunction with the equipment used.

  3. Determination of homovanillic acid and vanillylmandelic acid in urine of autistic children by gas chromatography/mass spectrometry.

    PubMed

    Kałuzna-Czaplińska, Joanna; Socha, Ewa; Rynkowski, Jacek

    2010-09-01

    Studies suggest dopamine nervous systems are involved in the pathogenesis of autistic disorder. Quantification of urinary homovanillic acid (HVA) and vanillylmandelic acid (VMA) can be a very important tool in the study of disorders of dopamine metabolism in autistic children. The urine specimens were collected from 20 autistic children and 36 neurologically normal children. Urinary HVA and VMA were simultaneously analyzed by gas chromatography-mass spectrometry. The method involves extraction of HVA and VMA from urinary samples and derivatization to N,O-bis(trimethylsilyl)trifluoroacetamide derivatives. The detection limits are 0.15 microg/mL and 0.23 microg/mL for VMA and HVA, respectively. The levels of HVA and VMA were higher in the urine of autistic children (28.8+/-15.5 micromol/mmol creatinine and 22.2+/-13.0 micromol/mmol creatinine, respectively) compared with those of the generally healthy children (4.6+/-0.7 micromol/mmol creatinine for HVA and 3.8+/-0.6 micromol/mmol creatinine for VMA). We proposed a simple, rapid method for a routine analysis of human urine to detect HVA and VMA related to an abnormal functional imbalance of the dopamine system, and showed our experience of application of this method to patients with a diagnosis of autism spectrum disorders. These results suggest significant differences in the levels of HVA and VMA between autistic and healthy children.

  4. The impact of proximal femoral morphology on failure strength with a mid-head resection short-stem hip arthroplasty.

    PubMed

    Olsen, Michael; Al Saied, Mohamed; Morison, Zachary; Sellan, Michael; Waddell, James P; Schemitsch, Emil H

    2014-12-01

    Mid-head resection short-stem hip arthroplasty is a conservative alternative to conventional total hip replacement and addresses proximal fixation challenges in patients not suitable for hip resurfacing. It is unclear whether proximal femoral morphology impacts the ultimate failure load of mid-head resection implanted femurs, thus the aim of this study was to investigate the effect of native neck-shaft angle (NSA) and coronal implant alignment on proximal femoral strength. In total, 36 synthetic femurs with two different proximal femoral morphologies were utilized in this study. Of them, 18 femurs with a varus NSA of 120° and 18 femurs with a valgus NSA of 135° were each implanted with a mid-head resection prosthesis. Femurs within the two different femoral morphology groups were divided into three equal coronal implant alignment groups: 10° valgus, 10° varus or neutral alignment. Prepared femurs were tested for stiffness and to failure in axial compression. There was no significant difference in stiffness nor failure load between femurs implanted with valgus-, varus- or neutrally aligned implants in femurs with a NSA of 120° (p = 0.396, p = 0.111, respectively). Femurs implanted in valgus orientation were significantly stiffer and failed at significantly higher loads than those implanted in varus alignment in femurs with a NSA of 135° (p = 0.001, p = 0.007, respectively). A mid-head resection short-stem hip arthroplasty seems less sensitive to clinically relevant variations of coronal implant alignment and may be more forgiving upon implantation in some femoral morphologies, however, a relative valgus component alignment is recommended. © IMechE 2014.

  5. Sex differences in plasma homovanillic acid levels in schizophrenia and normal controls: relation to neuroleptic resistance.

    PubMed

    Sumiyoshi, T; Hasegawa, M; Jayathilake, K; Meltzer, H Y

    1997-03-01

    Plasma homovanillic acid (pHVA) levels were compared in a large number of neuroleptic-resistant and -responsive schizophrenic patients (male/female = 161/46) and normal controls (67/27), and correlated with various measures of psychopathology. Psychopathology was evaluated with the brief psychiatric rating scale, the Schedule for Affective Disorders and Schizophrenia-Change version (SADS-C) and SADS-C Global Assessment Scale, the Scale for Assessment of Negative Symptoms, the Scale for Assessment of Positive Symptoms (SAPS), and the Quality of Life Scale. No significant differences in pHVA levels between neuroleptic-resistant (n = 104) or -responsive (n = 103) schizophrenic patients, and normal controls, were found; however, there was a main effect for sex, due to higher pHVA levels in women than men. There were no diagnosis x gender or age effects on pHVA levels. No significant correlations were observed between psychopathology ratings and baseline pHVA levels, except with the Hallucinations subscale of SAPS in neuroleptic-responsive patients. Neither duration of neuroleptic washout nor plasma prolactin levels correlated with pHVA levels. Further studies on the origin and significance of the gender difference in pHVA are indicated.

  6. Angle performance on optima MDxt

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    David, Jonathan; Kamenitsa, Dennis

    2012-11-06

    Angle control on medium current implanters is important due to the high angle-sensitivity of typical medium current implants, such as halo implants. On the Optima MDxt, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through six narrow slits, and any angle adjustment is made by electrostatically steering the beam, while cross-wafer beam parallelism is adjusted by changing the focus of the electrostatic parallelizing lens (P-lens). In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightlymore » tilting the wafer platen prior to implant. A variety of tests were run to measure the accuracy and repeatability of Optima MDxt's angle control. SIMS profiles of a high energy, channeling sensitive condition show both the cross-wafer angle uniformity, along with the small-angle resolution of the system. Angle repeatability was quantified by running a channeling sensitive implant as a regular monitor over a seven month period and measuring the sheet resistance-to-angle sensitivity. Even though crystal cut error was not controlled for in this case, when attributing all Rs variation to angle changes, the overall angle repeatability was measured as 0.16 Degree-Sign (1{sigma}). A separate angle repeatability test involved running a series of V-curves tests over a four month period using low crystal cut wafers selected from the same boule. The results of this test showed the angle repeatability to be <0.1 Degree-Sign (1{sigma}).« less

  7. Do Ergogenic Aids Alter Lower Extremity Joint Alignment During a Functional Movement Lunge Prior to and Following an Exercise Bout?

    PubMed Central

    Mills, Chris; Knight, James; Milligan, Gemma

    2015-01-01

    Ergogenic aids have been used to alter joint kinematics in an attempt to minimise injury risk, yet the effectiveness of these aids may be compromised following a bout of exercise. This preliminary study aimed to measure the effect of compression garments and Kinesio Tape® on lower extremity joint alignment prior to and following an exercise bout. Eight male athletes (age = 24.1 ± 3.0 years, body height = 177.4 ± 5.2 cm, body mass = 72.3 ± 7.2 kg) volunteered to participant in this study. Joint kinematics were recorded whilst all participants performed three rotational lunges, in three conditions (control, compression garment, Kinesio Tape®), prior to and following a 10 minute exercise bout. Frontal plane kinematics (lateral pelvic tilt, knee valgus, ankle inversion/eversion) were used to assess ergogenic aid effectiveness during the lunge. Participants exhibited no significant differences in joint kinematics between ergogenic aid conditions prior to the exercise bout. Following exercise the only significant difference occurred within the Kinesio Tape® condition where maximum knee valgus angle significantly increased from 6.5° prior to exercise, to 7.7° following the exercise bout. The results of this study suggest joint kinematics are not affected by the ergogenic aids in this study prior to an exercise bout. However, there is evidence to suggest that the application of Kinesio Tape® may allow an increase in knee valgus angle following a bout of exercise, yet, compression garments are effective at maintaining joint alignment following a bout of exercise. PMID:25964805

  8. Plasma homovanillic acid and family history of psychotic disorders in bipolar I patients.

    PubMed

    Zumárraga, Mercedes; Dávila, Ricardo; Basterreche, Nieves; Arrue, Aurora; Goienetxea, Biotza; González-Torres, Miguel Angel; Guimón, José

    2009-04-01

    It has been suggested that the family history of psychotic disorders is useful in defining homogeneous groups of bipolar patients. The plasma homovanillic acid (pHVA) concentrations have been related to the effect of antipsychotic treatment in psychotic patients. We have studied the influence of a positive family history of psychotic disorders both on the variation of pHVA levels and on the relation between pHVA concentrations and the clinical response to treatment. Clinical status and pHVA levels were assessed in 58 medication free patients before and after 4 weeks of treatment with olanzapine and lithium. Clinical improvement correlated positively with pHVA levels on the 28th day of treatment only in the patients having first degree relatives with psychotic disorders. The pHVA levels did not decrease after 28 days of treatment. Our results reinforce the idea that a positive family history of psychosis in psychotic bipolar disorders may constitute a good basis for sub-grouping these patients.

  9. The biomechanical evaluation of a novel 3-strand docking technique for ulnar collateral ligament reconstruction in the elbow.

    PubMed

    Williams, Phillip N; McGarry, Michelle H; Ihn, Hansel; Schulz, Brian M; Limpisvasti, Orr; ElAttrache, Neal S; Lee, Thay Q

    2018-05-07

    The original 2-strand docking technique for elbow ulnar collateral ligament reconstruction has recently been modified to use a 3-strand graft. To date, no biomechanical study has compared the 2 techniques. We hypothesized that the 3-strand docking technique would restore valgus laxity to its native state, with comparable load-to-failure characteristics to the 2-strand docking technique. Sixteen fresh cadaveric elbows were matched to the corresponding contralateral side from the same individual to create 8 matched pairs and were then randomized to undergo ulnar collateral ligament reconstruction using either the 2- or 3-strand technique. Valgus laxity and rotation measurements were quantified using a MicroScribe 3DLX digitizer at various flexion angles for the native state, transected state, and 1 of the 2 tested reconstructed ligaments. Each reconstruction was then tested to failure. Valgus laxity for the intact state at elbow flexion angles of 30°, 60°, 90°, and 120° was 7° ± 2°, 7° ± 2°, 6° ± 1°, and 5° ± 2°, respectively. These values were similar to those of both reconstruction techniques. On load-to-failure testing, there was no significant difference in any parameter recorded. Yield torques for the 3- and 2-strand reconstructions were 13.4 ± 4.80 N/m and 11.8 ± 4.76 N/m, respectively (P = .486). The ultimate torques were 15.7 ± 6.10 N/m and 14.4 ± 5.58 N/m for the 3- and 2-strand techniques, respectively (P = .582). The 3-strand docking technique was able to restore valgus laxity to the native state, with similar load-to-failure characteristics to the 2-strand docking technique. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.

  10. Heterogeneity in plasma homovanillic Acid levels in schizophreniform disorder.

    PubMed

    Pradhan, N; Harihar, C; Das, P; Andrade, C

    1992-04-01

    Plasma homovanillic acid (pHVA) levels were estimated in 20 cases of schizophreniform disorder, 14 cases of schizophrenia 'on medication' and 17 cases of schizophrenia 'off medication'. A bimodal distribution of pHVA was seen in schizophreniform disorder subjects, suggesting heterogenous groups in terms of dopaminergic function. No significant difference in the pHVA values was seen in the 3 groups, nor was there a relationship between the severity of the illness and the pHVA values; these results suggest plasticity of the dopaminergic system to neuroleptics.

  11. Assessment of central dopaminergic function using plasma-free homovanillic acid after debrisoquin administration.

    PubMed

    Riddle, M A; Leckman, J F; Cohen, D J; Anderson, M; Ort, S I; Caruso, K A; Shaywitz, B A

    1986-01-01

    Central dopaminergic (DA) function in children and adults was assessed by monitoring plasma-free levels of the dopamine metabolite homovanillic acid (pHVA) before and after a single oral dose and chronic oral administration of debrisoquin. Debrisoquin inhibits peripheral metabolism of dopamine to HVA and does not cross the blood-brain barrier. By reducing peripheral formation of HVA through the use of debrisoquin, the remaining HVA in plasma more accurately reflects central DA activity. Debrisoquin administration resulted in marked reductions of pHVA in each of 12 patients studied. Eleven of the 12 subjects tolerated debrisoquin without physical or behavioral side effects. The debrisoquin administration method appears to be a safe and potentially valid technique for evaluating aspects of central dopaminergic function in children and adults.

  12. Relationship between plasma homovanillic acid and outcome in patients with psychosis spectrum disorders.

    PubMed

    van de Kerkhof, Nora W A; Fekkes, Durk; van der Heijden, Frank M M A; Egger, Jos I M; Verhoeven, Willem M A

    2015-01-01

    Psychosis spectrum disorders, especially schizophrenia, have been linked to disturbed dopaminergic activity in the brain. Plasma homovanillic acid (pHVA) levels partly represent dopaminergic metabolism in the central nervous system. In the present study associations between (changes in) pHVA levels, symptom severity and symptomatic improvement in patients with psychoses were investigated. From a total of 80 patients, 58 fulfilled all inclusion criteria and their symptom profile and severity were assessed by means of the Comprehensive Assessment of Symptoms and History (CASH), the Positive and Negative Syndrome Scale (PANSS) and the Clinical Global Impression Scale for Severity and Improvement (CGI-S/CGI-I) at baseline and after 6 weeks of antipsychotic treatment. After inclusion, all patients were prescribed first- or second-generation antipsychotics by their treating psychiatrist. A total of 12 patients had first-episode psychosis (FEP). At both time points, pHVA levels were measured. Subsequently, pHVA levels were compared with an age-matched control sample and changes in pHVA levels (ΔpHVA) after treatment were associated with clinical parameters. Before analyses, data were scrutinized for possible confounders, particularly gender, smoking, medication status (including antipsychotic class), and recent drug use. The pHVA levels in patients were not different from those in controls. Treatment resulted in a significant decrease of all parameters. Symptomatic improvement as well as ΔpHVA was most pronounced in FEP patients. These findings show that patients with FEP have a more favourable outcome than non-FEP patients and that greater ΔpHVA also suggests that FEP patients still have the capacity to adjust dopaminergic neurotransmission. © 2015 S. Karger AG, Basel.

  13. Results of computer assisted mini-incision subvastus approach for total knee arthroplasty.

    PubMed

    Turajane, Thana; Larbpaiboonpong, Viroj; Kongtharvonskul, Jatupon; Maungsiri, Samart

    2009-12-01

    Mini-incision subvastus approach is soft tissue preservation of the knee. Advantages of the mini-incision subvastus approach included reduced blood loss, reduced pain, self rehabilitation and faster recovery. However, the improved visualization, component alignment, and more blood preservation have been debatable to achieve the better outcome and preventing early failure of the Total Knee Arthroplasty (TKA). The computer navigation has been introduced to improve alignment and blood loss. The purpose of this study was to evaluate the short term outcomes of the combination of computer assisted mini-incision subvastus approach for Total Knee Arthroplasty (CMS-TKA). A prospective case series of the initial 80 patients who underwent computer assisted mini-incision subvastus approach for CMS-TKA from January 2007 to October 2008 was carried out. The patients' conditions were classified into 2 groups, the simple OA knee (varus deformity was less than 15 degree, BMI was less than 20%, no associated deformities) and the complex deformity (varus deformity was more than 15 degrees, BMI more was than 20%, associated with flexion contractor). There were 59 patients in group 1 and 21 patients in group 2. Of the 80 knees, 38 were on the left and 42 on the right. The results of CMS-TKA [the mean (range)] in group 1: group 2 were respectively shown as the incision length [10.88 (8-13): 11.92 (10-14], the operation time [118 (111.88-125.12): 131 (119.29-143.71) minutes, lateral releases (0 in both groups), postoperative range of motion in flexion [94.5 (90-100): 95.25 (90-105) degree] and extension [1.75 (0-5): 1.5 (0-5) degree] Blood loss in 24 hours [489.09 (414.7-563.48): 520 (503.46-636.54) ml] and blood transfusion [1 (0-1) unit? in both groups], Tibiofemoral angle preoperative [Varus = 4 (varus 0-10): Varus = 17.14 (varus 15.7-18.5) degree, Tibiofemoral angle postoperative [Valgus = 1.38 (Valgus 0-4): Valgus = 2.85 (valgus 2.1-3.5) degree], Tibiofemoral angle outlier (85% both

  14. Psychopathological and nutritional correlates of plasma homovanillic acid in adolescents with anorexia nervosa.

    PubMed

    Castro-Fornieles, Josefina; Deulofeu, Ramón; Baeza, Immaculada; Casulà, Vanessa; Saura, Begoña; Lázaro, Luisa; Puig, Josefina; Toro, Josep; Bernardo, Miquel

    2008-02-01

    Dopaminergic abnormalities have been described in anorexia nervosa but studies about plasma level of homovanillic acid (pHVA) have yielded conflicting results probably due to the small number and the heterogeneity of patients. Plasma HVA, nutritional and hormonal parameters and several scales - the Eating Attitudes Test (EAT), the Beck Depression Inventory (BDI), the Leyton Obsessional Inventory-child version (LOI-C) and the State and Trait Anxiety Inventory (STAI) - were assessed in 44 adolescent anorexia nervosa patients (mean age 14.7 years, SD 1.7) consecutively admitted to an Eating Disorder Unit. They were evaluated at admission, at discharge and, in 34 cases, after 9 months of follow-up. pHVA was also assessed in 16 control adolescents. Patients had significantly higher pHVA than controls (p = .002). About 31% of patients had a very high level of pHVA, a significantly higher (p = .006) mean score in the BDI and a non significantly higher mean score in the EAT. After weight recovery some laboratory parameters improved as well as the EAT (p = .019), the BDI (p = 001) and the Interference score of the LOI-C (p = .004). Moreover, pHVA decreased significantly (p=.036). At follow-up, patients with normal weight had lower (p = .037) pHVA than patients with low weight. The conclusion would be that there is a dopaminergic dysfunction in anorexic patients, specially in a subgroup with high depressive and anorexic symptomatology. With weight recovery and psychopathological improvement, pHVA tends to normalization.

  15. HETEROGENEITY IN PLASMA HOMOVANILLIC ACID LEVELS IN SCHIZOPHRENIFORM DISORDER

    PubMed Central

    Pradhan, N.; Harihar, C.; Das, P.; Andrade, C.

    1992-01-01

    Plasma homovanillic acid (pHVA) levels were estimated in 20 cases of schizophreniform disorder, 14 cases of schizophrenia ‘on medication’ and 17 cases of schizophrenia ‘off medication’. A bimodal distribution of pHVA was seen in schizophreniform disorder subjects, suggesting heterogenous groups in terms of dopaminergic function. No significant difference in the pHVA values was seen in the 3 groups, nor was there a relationship between the severity of the illness and the pHVA values; these results suggest plasticity of the dopaminergic system to neuroleptics. PMID:21776112

  16. Differential effects of mental stress on plasma homovanillic acid in schizophrenia and normal controls.

    PubMed

    Sumiyoshi, T; Saitoh, O; Yotsutsuji, T; Itoh, H; Kurokawa, K; Kurachi, M

    1999-04-01

    We previously reported that mental stress by Kraepelin's arithmetic test decreases plasma homovanillic acid (pHVA) levels in psychiatrically normal healthy human subjects. The present study was undertaken to determine whether this pattern of changes in pHVA concentrations resulting from mental stress is altered in patients with schizophrenia. Fourteen male patients with schizophrenia including those under ongoing neuroleptic treatment and 14 normal male volunteers participated in the study. Following overnight fast and restricted physical activity, the subjects performed Kraepelin's arithmetic test for 30 minutes. Plasma samples were collected immediately before and after the test for measurement of pHVA levels. A significant diagnosis by Kraepelin's test effect was observed due to a decrease in pHVA levels by the Kraepelin test in control subjects but not in patients with schizophrenia. Changes in pHVA levels during the Kraepelin test positively correlated with pre-test pHVA levels in control subjects, while this correlation was not observed in patients with schizophrenia. These results may be further support for the presence of a dopamine-dependent restitutive system in the brain. The absence of response of pHVA levels to mental stress in patients with schizophrenia may indicate that the dopamine restitutive system in these patients is disrupted or already down-regulated, as previously predicted.

  17. Prediction of short-term changes in symptom severity by baseline plasma homovanillic acid levels in schizophrenic patients receiving clozapine.

    PubMed

    Sumiyoshi, T; Hasegawa, M; Jayathilake, K; Meltzer, H Y

    1997-03-24

    The relationship between pretreatment levels of plasma homovanillic acid (pHVA) and the outcome of clozapine treatment was studied in 18 male patients with schizophrenia who were resistant to treatment with conventional neuroleptics. After 6 months of clozapine treatment, 7 patients demonstrated > or = 20% decrease in the Brief Psychiatric Rating Scale (BPRS) (responders), while 11 patients did not (non-responders). Responders and non-responders did not differ with respect to the baseline pHVA level. The BPRS Positive Symptom scores at 6 weeks and 3 months, but not those at baseline and 6 months, following initiation of clozapine treatment negatively correlated with pHVA levels for all patients. The correlations became stronger when only responders were included. No significant correlation between Positive Symptom scores and pHVA levels was observed for non-responders. The BPRS Total and Negative Symptom scores did not correlate with pHVA for all patients, responders or non-responders at any time. The percent decrease in the BPRS Positive Symptom scores from baseline at 6 weeks following clozapine treatment correlated significantly with pHVA levels in responders. These results suggest that pretreatment levels of pHVA can be used to predict relatively short-term changes in the positive symptoms of patients with schizophrenia receiving clozapine treatment, particularly for clozapine responders.

  18. Angle classification revisited 2: a modified Angle classification.

    PubMed

    Katz, M I

    1992-09-01

    Edward Angle, in his classification of malocclusions, appears to have made Class I a range of abnormality, not a point of ideal occlusion. Current goals of orthodontic treatment, however, strive for the designation "Class I occlusion" to be synonymous with the point of ideal intermeshing and not a broad range. If contemporary orthodontists are to continue to use Class I as a goal, then it is appropriate that Dr. Angle's century-old classification, be modified to be more precise.

  19. Vaccination Enhances Early Immune Responses in White Shrimp Litopenaeus vannamei after Secondary Exposure to Vibrio alginolyticus

    PubMed Central

    Lin, Yong-Chin; Chen, Jiann-Chu; Morni, Wan Zabidii W.; Putra, Dedi Fazriansyah; Huang, Chien-Lun; Li, Chang-Che; Hsieh, Jen-Fang

    2013-01-01

    Background Recent work suggested that the presence of specific memory or some form of adaptive immunity occurs in insects and shrimp. Hypervariable pattern recognition molecules, known as Down syndrome cell adhesion molecules, are able to mount specific recognition, and immune priming in invertebrates. In the present study, we attempted to understand the immune response pattern of white shrimp Litopenaeus vannamei which received primary (PE) and secondary exposure (SE) to Vibrio alginolyticus. Methodology Immune parameters and proliferation of haematopoietic tissues (HPTs) of shrimp which had received PE and SE to V. alginolyticus were measured. In the PE trial, the immune parameters and proliferation of HPTs of shrimp that received heat-killed V. alginolyticus (HVa) and formalin-inactivated V. alginolyticus (FVa) were measured. Mortality, immune parameters and proliferation of HPTs of 7-day-HVa-PE shrimp (shrimp that received primary exposure to HVa after 7 days) and 7-day-FVa-PE shrimp (shrimp that received primary exposure to FVa after 7 days) following SE to live V. alginolyticus (LVa) were measured. Phagocytic activity and clearance efficiency were examined for the 7∼35-day-HVa-PE and FVa-PE shrimp. Results HVa-receiving shrimp showed an earlier increase in the immune response on day 1, whereas FVa-receiving shrimp showed a late increase in the immune response on day 5. The 7-day-FVa-PE shrimp showed enhancement of immunity when encountering SE to LVa, whereas 7-day-HVa-PE shrimp showed a minor enhancement in immunity. 7-day-FVa-PE shrimp showed higher proliferation and an HPT mitotic index. Both phagocytic activity and clearance maintained higher for both HVa-PE and FVa-PE shrimp after 28 days. Conclusions HVa- and FVa-receiving shrimp showed the bacteria agglutinated prior to being phagocytised. FVa functions as a vaccine, whereas HVa functions as an inducer and can be used as an immune adjuvant. A combined mixture of FVa and HVa can serve as a

  20. [Spectral Study on the Effects of Angle-Tuned Filter Wedge Angle Parameter to Reflecting Characteristics].

    PubMed

    Yu, Kan; Huang, De-xiu; Yin, Juan-juan; Bao, Jia-qi

    2015-08-01

    Three-port tunable optical filter is a key device in the all-optic intelligent switching network and dense wavelength division multiplexing system. The characteristics of the reflecting spectrum, especially the reflectivity and the isolation degree are very important to the three-port filter. Angle-tuned thin film filter is widely used as a three-port tunable filter for its high rectangular degree and good temperature stability. The characteristics of the reflecting spectrum are greatly influenced not only by the incident angle, but also by the wedge angle parameter of the non-paralleled wedge thin film filter. In the present paper, the influences of the wedge angle parameter to the reflectivity and the half bandwidth are analyzed, and the reflecting spectrum characterstics are simulationed in different wedge angle parameter and polarity. The wedge angle-tuned thin film filter with 0.8° wedge angle parameter is fabricated. The experimental results show that keeping the wedge angle the same orientation to the incident angle will worsen the reflectivity and the rectangular degree of the reflecting spectrum. However, keeping the wedge angle orientation reverse to the incident angle will enhance the reflectivity and decrease the bandwidth, which will give higher reflectivity and isolation degree to the three-port filter than that of high parallel degree angle-tuned thin film filter.

  1. A predictive factor for acquiring an ideal lower limb realignment after opening-wedge high tibial osteotomy.

    PubMed

    Bito, Haruhiko; Takeuchi, Ryohei; Kumagai, Ken; Aratake, Masato; Saito, Izumi; Hayashi, Riku; Sasaki, Yohei; Aota, Yoichi; Saito, Tomoyuki

    2009-04-01

    Obtaining a correct postoperative limb alignment is an important factor in achieving a successful clinical outcome after an opening-wedge high tibial osteotomy (OWHTO). To better predict some of the aspects that impact upon the clinical outcomes following this procedure, including postoperative correction loss and over correction, we examined the changes in the frontal plane of the lower limb in a cohort of patients who had undergone OWHTO using radiography. Forty-two knees from 33 patients (23 cases of osteoarthritis and 10 of osteonecrosis) underwent a valgus realignment OWHTO procedure and were radiographically assessed for changes that occurred pre- and post-surgery. The mean femorotibial angle (FTA) was found to be 182.1 +/- 2.0 degrees (12 +/- 2.0 anatomical varus angulation) preoperatively and 169.6 +/- 2.4 degrees (10.4 +/- 2.4 anatomical valgus angulation) postoperatively. These measurements thus revealed significant changes in the weight bearing line ratio (WBL), femoral axis angle (FA), tibial axis angle (TA), tibia plateau angle (TP), tibia vara angle (TV) and talar tilt angle (TT) following OWHTO. In contrast, no significant change was found in the weight bearing line angle (WBLA) after these treatments. To assess the relationship between the correction angle and these indexes, 42 knees were divided into the following three groups according to the postoperative FTA; a normal correction group (168 degrees < or = FTA < or = 172 degrees ), an over-correction group (FTA < 168 degrees ), and an under-correction group (FTA > 172 degrees ). There were significant differences in the delta angle [DA; calculated as (pre FTA - post FTA) - (pre TV - post TV)] among each group of patients. Our results thus indicate a negative correlation between the DA and preoperative TA (R(2) = 0.148, p < 0.05). Hence, given that the correction errors in our patients appear to negatively correlate with the preoperative TA, postoperative malalignments are likely to be predictable

  2. Angle Performance on Optima XE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    David, Jonathan; Satoh, Shu

    2011-01-07

    Angle control on high energy implanters is important due to shrinking device dimensions, and sensitivity to channeling at high beam energies. On Optima XE, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through a series of narrow slits, and any angle adjustment is made by steering the beam with the corrector magnet. In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightly tilting the wafer platen during implant.Using a sensitive channeling condition, we were ablemore » to quantify the angle repeatability of Optima XE. By quantifying the sheet resistance sensitivity to both horizontal and vertical angle variation, the total angle variation was calculated as 0.04 deg. (1{sigma}). Implants were run over a five week period, with all of the wafers selected from a single boule, in order to control for any crystal cut variation.« less

  3. Manifold angles, the concept of self-similarity, and angle-enhanced bifurcation diagrams

    PubMed Central

    Beims, Marcus W.; Gallas, Jason A. C.

    2016-01-01

    Chaos and regularity are routinely discriminated by using Lyapunov exponents distilled from the norm of orthogonalized Lyapunov vectors, propagated during the temporal evolution of the dynamics. Such exponents are mean-field-like averages that, for each degree of freedom, squeeze the whole temporal evolution complexity into just a single number. However, Lyapunov vectors also contain a step-by-step record of what exactly happens with the angles between stable and unstable manifolds during the whole evolution, a big-data information permanently erased by repeated orthogonalizations. Here, we study changes of angles between invariant subspaces as observed during temporal evolution of Hénon’s system. Such angles are calculated numerically and analytically and used to characterize self-similarity of a chaotic attractor. In addition, we show how standard tools of dynamical systems may be angle-enhanced by dressing them with informations not difficult to extract. Such angle-enhanced tools reveal unexpected and practical facts that are described in detail. For instance, we present a video showing an angle-enhanced bifurcation diagram that exposes from several perspectives the complex geometrical features underlying the attractors. We believe such findings to be generic for extended classes of systems. PMID:26732416

  4. Manifold angles, the concept of self-similarity, and angle-enhanced bifurcation diagrams

    NASA Astrophysics Data System (ADS)

    Beims, Marcus W.; Gallas, Jason A. C.

    2016-01-01

    Chaos and regularity are routinely discriminated by using Lyapunov exponents distilled from the norm of orthogonalized Lyapunov vectors, propagated during the temporal evolution of the dynamics. Such exponents are mean-field-like averages that, for each degree of freedom, squeeze the whole temporal evolution complexity into just a single number. However, Lyapunov vectors also contain a step-by-step record of what exactly happens with the angles between stable and unstable manifolds during the whole evolution, a big-data information permanently erased by repeated orthogonalizations. Here, we study changes of angles between invariant subspaces as observed during temporal evolution of Hénon’s system. Such angles are calculated numerically and analytically and used to characterize self-similarity of a chaotic attractor. In addition, we show how standard tools of dynamical systems may be angle-enhanced by dressing them with informations not difficult to extract. Such angle-enhanced tools reveal unexpected and practical facts that are described in detail. For instance, we present a video showing an angle-enhanced bifurcation diagram that exposes from several perspectives the complex geometrical features underlying the attractors. We believe such findings to be generic for extended classes of systems.

  5. Plasma homovanillic acid in untreated schizophrenia--relationship with symptomatology and sex.

    PubMed

    Zhang, Z J; Peet, M; Ramchand, C N; Shah, S; Reynolds, G P

    2001-01-01

    Plasma homovanillic acid (pHVA) concentrations are considered to reflect, in part, central dopamine metabolism and thus may be of value in assessing the role of dopamine neurotransmission in schizophrenia. Furthermore, some recent studies have suggested a relationship of pHVA with symptomatology. We have undertaken a study of pHVA in a large cohort of unmedicated DSM-IV schizophrenic patients in order to assess the relationship of pHVA to various clinical parameters. pHVA in 58 drug-free patients (10.11+/-0.52 ng/ml) was significantly elevated in comparison with 62 matched control subjects (8.77+/-0.39 ng/ml). pHVA was found to be higher in patients with a more negative syndrome. No significant correlation of pHVA with overall SAPS or SANS scores was apparent in the patients although, within the SANS subscales, a significant relationship to anhedonia-asociality was apparent. Interestingly, the male drug-free patients showed a correlation of pHVA with negative symptoms defined by SANS and several SANS subscales, while females showed no significant relationship with any SANS subscales. The results may suggest that an increased dopaminergic turnover is apparent in (male) schizophrenic patients with predominantly negative symptoms, providing some support for reports that this change in neuronal activity may be related to the neuropathological abnormalities seen in the disease, which may themselves differ between males and females. Such neuronal deficits of developmental or degenerative origin may thus result in an elevation/disinhibition of central dopamine metabolism in schizophrenia.

  6. Setting the magic angle for fast magic-angle spinning probes.

    PubMed

    Penzel, Susanne; Smith, Albert A; Ernst, Matthias; Meier, Beat H

    2018-06-15

    Fast magic-angle spinning, coupled with 1 H detection is a powerful method to improve spectral resolution and signal to noise in solid-state NMR spectra. Commercial probes now provide spinning frequencies in excess of 100 kHz. Then, one has sufficient resolution in the 1 H dimension to directly detect protons, which have a gyromagnetic ratio approximately four times larger than 13 C spins. However, the gains in sensitivity can quickly be lost if the rotation angle is not set precisely. The most common method of magic-angle calibration is to optimize the number of rotary echoes, or sideband intensity, observed on a sample of KBr. However, this typically uses relatively low spinning frequencies, where the spinning of fast-MAS probes is often unstable, and detection on the 13 C channel, for which fast-MAS probes are typically not optimized. Therefore, we compare the KBr-based optimization of the magic angle with two alternative approaches: optimization of the splitting observed in 13 C-labeled glycine-ethylester on the carbonyl due to the Cα-C' J-coupling, or optimization of the H-N J-coupling spin echo in the protein sample itself. The latter method has the particular advantage that no separate sample is necessary for the magic-angle optimization. Copyright © 2018. Published by Elsevier Inc.

  7. A Different Angle on Perspective

    ERIC Educational Resources Information Center

    Frantz, Marc

    2012-01-01

    When a plane figure is photographed from different viewpoints, lengths and angles appear distorted. Hence it is often assumed that lengths, angles, protractors, and compasses have no place in projective geometry. Here we describe a sense in which certain angles are preserved by projective transformations. These angles can be constructed with…

  8. The gonial angle stripper: an instrument for the treatment of prominent gonial angle.

    PubMed

    Kyutoku, S; Yanagida, A; Kusumoto, K; Ogawa, Y

    1994-12-01

    In the Orient, a prominent gonial angle, so-called benign masseteric hypertrophy, is rather common and considered unattractive. Therefore, its surgical correction is one of the most popular forms of facial skeletal contouring. For accurate and safe osteotomy of the mandibular angle region, a gonial angle stripper was specially invented. It has a small projection that will ease identification of the osteotomy line in a narrow operative field. The tool has been clinically used in eight patients to prove its usefulness, especially for a posteriorly developed mandibular angle.

  9. Biomechanical Effects of an Injury Prevention Program in Preadolescent Female Soccer Athletes

    PubMed Central

    Thompson, Julie A.; Tran, Andrew A.; Gatewood, Corey T.; Shultz, Rebecca; Silder, Amy; Delp, Scott L.; Dragoo, Jason L.

    2017-01-01

    Background Anterior cruciate ligament (ACL) injuries are common, and children as young as 10 years of age exhibit movement patterns associated with an ACL injury risk. Prevention programs have been shown to reduce injury rates, but the mechanisms behind these programs are largely unknown. Few studies have investigated biomechanical changes after injury prevention programs in children. Purpose/Hypothesis To investigate the effects of the F-MARC 11+ injury prevention warm-up program on changes to biomechanical risk factors for an ACL injury in preadolescent female soccer players. We hypothesized that the primary ACL injury risk factor of peak knee valgus moment would improve after training. In addition, we explored other kinematic and kinetic variables associated with ACL injuries. Study Design Controlled laboratory study. Methods A total of 51 female athletes aged 10 to 12 years were recruited from soccer clubs and were placed into an intervention group (n = 28; mean [±SD] age, 11.8 ± 0.8 years) and a control group (n = 23; mean age, 11.2 ± 0.6 years). The intervention group participated in 15 in-season sessions of the F-MARC 11+ program (2 times/wk). Pre- and postseason motion capture data were collected during preplanned cutting, unanticipated cutting, double-leg jump, and single-leg jump tasks. Lower extremity joint angles and moments were estimated using OpenSim, a biomechanical modeling system. Results Athletes in the intervention group reduced their peak knee valgus moment compared with the control group during the double-leg jump (mean [±standard error of the mean] pre- to posttest change, −0.57 ± 0.27 %BW×HT vs 0.25 ± 0.25 %BW×HT, respectively; P = .034). No significant differences in the change in peak knee valgus moment were found between the groups for any other activity; however, the intervention group displayed a significant pre- to posttest increase in peak knee valgus moment during unanticipated cutting (P = .044). Additional analyses

  10. Plasma catecholamine metabolites in schizophrenics: evidence for the two-subtype concept.

    PubMed

    Chang, W H; Chen, T Y; Lin, S K; Lung, F W; Lin, W L; Hu, W H; Yeh, E K

    1990-03-01

    Plasma homovanillic acid (pHVA) and plasma methoxyhydroxyphenyl glycol (pMHPG), as well as plasma haloperidol, were measured in 33 schizophrenic patients before and during 6 weeks of haloperidol treatment. Good responders had higher baseline pHVA values compared with poor responders (17.4 +/- 8.8 ng/ml, n = 22 versus 11.4 +/- 5.0 ng/ml, n = 11, p less than 0.05). A higher than 15 ng/ml pretreatment pHVA level was associated with a more consistent clinical response to the subsequent treatment. Differential pHVA changes during treatment were also found between good and poor responders. Within the good responder group, a significant decline in pHVA over time was found. By contrast, pHVA showed a transient increase in the poor responder group. Plasma MHPG changes showed a similar pattern during treatment in good responders, although no significant differences in baseline values were found between the good (n = 13) and poor (n = 9) responders, and pMHPG showed no change during treatment in poor responders. Significant correlations between baseline pHVA and pMHPG values were found in 22 patients. Good responders and poor responders did not differ significantly in terms of age, duration of illness, severity of presenting symptoms, haloperidol dose, or plasma drug concentration. Two hypothetical subtypes of schizophrenia and both dopamine and norepinephrine systems involved in schizophrenic psychopathology are proposed.

  11. Computer-assisted measurements of coronal knee joint laxity in vitro are related to low-stress behavior rather than structural properties of the collateral ligaments.

    PubMed

    Wilson, W T; Deakin, A H; Wearing, S C; Payne, A P; Clarke, J V; Picard, F

    2013-01-01

    The relationship between coronal knee laxity and the restraining properties of the collateral ligaments remains unknown. This study investigated correlations between the structural properties of the collateral ligaments and stress angles used in computer-assisted total knee arthroplasty (TKA), measured with an optically based navigation system. Ten fresh-frozen cadaveric knees (mean age: 81 ± 11 years) were dissected to leave the menisci, cruciate ligaments, posterior joint capsule and collateral ligaments. The resected femur and tibia were rigidly secured within a test system which permitted kinematic registration of the knee using a commercially available image-free navigation system. Frontal plane knee alignment and varus-valgus stress angles were acquired. The force applied during varus-valgus testing was quantified. Medial and lateral bone-collateral ligament-bone specimens were then prepared, mounted within a uni-axial materials testing machine, and extended to failure. Force and displacement data were used to calculate the principal structural properties of the ligaments. The mean varus laxity was 4 ± 1° and the mean valgus laxity was 4 ± 2°. The corresponding mean manual force applied was 10 ± 3 N and 11 ± 4 N, respectively. While measures of knee laxity were independent of the ultimate tensile strength and stiffness of the collateral ligaments, there was a significant correlation between the force applied during stress testing and the instantaneous stiffness of the medial (r = 0.91, p = 0.001) and lateral (r = 0.68, p = 0.04) collateral ligaments. These findings suggest that clinicians may perceive a rate of change of ligament stiffness as the end-point during assessment of collateral knee laxity.

  12. Survival and Growth of Cottonwood Clones After Angle Planting and Base Angle Treatments

    Treesearch

    W.K. Randall; Harvey E. Kennedy

    1976-01-01

    Presently, commercial cottonwood plantations in the lower Mississippi Valley are established using vertically planted, unrooted cuttings with a flat (90°) base. Neither survival nor first-year growth of a group of six Stoneville clones was improved by angle planting or cutting base angles diagonally. For one clone, survival was significantly better when base angle was...

  13. Photoelectric angle converter

    NASA Astrophysics Data System (ADS)

    Podzharenko, Volodymyr A.; Kulakov, Pavlo I.

    2001-06-01

    The photo-electric angle transmitter of rotation is offered, at which the output voltage is linear function of entering magnitude. In a transmitter the linear phototransducer is used on the basis of pair photo diode -- operating amplifier, which output voltage is linear function of the area of an illuminated photosensitive stratum, and modulator of a light stream of the special shape, which ensures a linear dependence of this area from an angle of rotation. The transmitter has good frequent properties and can be used for dynamic measurements of an angular velocity and angle of rotation, in systems of exact drives and systems of autocontrol.

  14. P-type calcium channels in rat neocortical neurones.

    PubMed Central

    Brown, A M; Sayer, R J; Schwindt, P C; Crill, W E

    1994-01-01

    1. The high threshold, voltage-activated (HVA) calcium current was recorded from acutely isolated rat neocortical pyramidal neurones using the whole-cell patch technique to examine the effect of agents that block P-type calcium channels and to compare their effects to those of omega-conotoxin GVIA (omega-CgTX) and nifedipine. 2. When applied at a saturating concentration (100 nM) the peptide toxins omega-Aga-IVA and synthetic omega-Aga-IVA blocked 31.5 and 33.0% of the HVA current respectively. 3. A saturating concentration of nifedipine (10 microM) inhibited 48.2% of the omega-Aga-IVA-sensitive current, whereas saturating concentrations of both omega-Aga-IVA (100 nM) and omega-CgTX (10 microM) blocked separate specific components of the HVA current. 4. Partially purified funnel web spider toxin (FTX) at a dilution of 1:1000 blocked 81.4% of the HVA current and occluded the inhibitory effect of omega-Aga-IVA. Synthetic FTX 3.3 arginine polyamine (sFTX) at a concentration of 1 mM blocked 61.2% of the HVA current rapidly and reversibly. The effects of sFTX were partially occluded by pre-application of omega-Aga-IVA. We conclude that neither FTX nor sFTX blocked a specific component of the HVA current in these cells. 5. In view of the specificity of omega-Aga-IVA for P-type calcium channels in other preparations and for a specific component of the HVA current in dissociated neocortical neurones we conclude that about 30% of the HVA current in these neurones flow through P-channels. PMID:7517449

  15. P-type calcium channels in rat neocortical neurones.

    PubMed

    Brown, A M; Sayer, R J; Schwindt, P C; Crill, W E

    1994-03-01

    1. The high threshold, voltage-activated (HVA) calcium current was recorded from acutely isolated rat neocortical pyramidal neurones using the whole-cell patch technique to examine the effect of agents that block P-type calcium channels and to compare their effects to those of omega-conotoxin GVIA (omega-CgTX) and nifedipine. 2. When applied at a saturating concentration (100 nM) the peptide toxins omega-Aga-IVA and synthetic omega-Aga-IVA blocked 31.5 and 33.0% of the HVA current respectively. 3. A saturating concentration of nifedipine (10 microM) inhibited 48.2% of the omega-Aga-IVA-sensitive current, whereas saturating concentrations of both omega-Aga-IVA (100 nM) and omega-CgTX (10 microM) blocked separate specific components of the HVA current. 4. Partially purified funnel web spider toxin (FTX) at a dilution of 1:1000 blocked 81.4% of the HVA current and occluded the inhibitory effect of omega-Aga-IVA. Synthetic FTX 3.3 arginine polyamine (sFTX) at a concentration of 1 mM blocked 61.2% of the HVA current rapidly and reversibly. The effects of sFTX were partially occluded by pre-application of omega-Aga-IVA. We conclude that neither FTX nor sFTX blocked a specific component of the HVA current in these cells. 5. In view of the specificity of omega-Aga-IVA for P-type calcium channels in other preparations and for a specific component of the HVA current in dissociated neocortical neurones we conclude that about 30% of the HVA current in these neurones flow through P-channels.

  16. Treatment with clozapine and its effect on plasma homovanillic acid and norepinephrine concentrations in schizophrenia.

    PubMed

    Davidson, M; Kahn, R S; Stern, R G; Hirschowitz, J; Apter, S; Knott, P; Davis, K L

    1993-02-01

    Measurement of plasma concentrations of the dopamine metabolite, homovanillic acid (pHVA), is an indirect tool to assess changes in dopamine turnover. Levels of pHVA have been reported to decrease during treatment with conventional antidopaminergic, neuroleptics, with the decrement correlating with symptomatic improvement in schizophrenic symptoms. Clozapine, an atypical neuroleptic, is the only drug proved to be effective in treatment-refractory patients. However, the mechanism mediating this unique efficacy has not been fully elucidated. This study examined the effect of clozapine on pHVA concentrations in schizophrenic patients. Since clozapine potently binds to alpha 2-adrenergic receptors, plasma norepinephrine (pNE) concentrations were also measured. Twenty-eight treatment-refractory schizophrenic patients (24 men, 4 women) were treated with clozapine (up to 600 mg/day) for 5 weeks, after a minimum 1-week drug-free period. Symptomatology and pHVA and pNE concentrations were measured at the last drug-free day and weekly for 5 weeks. Fourteen patients responded to clozapine treatment, while an equal number did not. Mean pHVA concentrations did not significantly change during treatment with clozapine. Although clozapine tended to lower pHVA concentrations in treatment responders, the effect was small and not significant. Clozapine treatment significantly raised pNE concentrations, but this did not differentiate responders from nonresponders to clozapine. These findings suggest that clozapine's effect on DA turnover is small and that clozapine may be effective in treatment-refractory schizophrenia by mechanisms other than, or in addition to, dopamine receptor blockade. However, since about one-third of NE is metabolized into HVA, the clozapine-induced increase in pNE may have overshadowed a possible lowering effect of clozapine on pHVA.

  17. Prediction of changes in memory performance by plasma homovanillic acid levels in clozapine-treated patients with schizophrenia.

    PubMed

    Sumiyoshi, Tomiki; Roy, A; Kim, C-H; Jayathilake, K; Lee, M A; Sumiyoshi, C; Meltzer, H Y

    2004-12-01

    Cognitive dysfunction in schizophrenia has been demonstrated to be dependent, in part, on dopaminergic activity. Clozapine has been found to improve some domains of cognition, including verbal memory, in patients with schizophrenia. This study tested the hypothesis that plasma homovanillic acid (pHVA) levels, a peripheral measure of central dopaminergic activity, would predict the change in memory performance in patients with schizophrenia treated with clozapine. Twenty-seven male patients with schizophrenia received clozapine treatment for 6 weeks. Verbal list learning (VLL)-Delayed Recall (VLL-DR), a test of secondary verbal memory, was administered before and after clozapine treatment. Blood samples to measure pHVA levels were collected at baseline. Baseline pHVA levels were negatively correlated with change in performance on VLL-DR; the lower baseline pHVA level was associated with greater improvement in performance on VLL-DR during treatment with clozapine. Baseline pHVA levels in subjects who showed improvement in verbal memory during clozapine treatment ( n=13) were significantly lower than those in subjects whose memory performance did not improve ( n=14). The results of this study indicate that baseline pHVA levels predict the ability of clozapine to improve memory performance in patients with schizophrenia.

  18. Lack of effect of laboratory-provoked anxiety on plasma homovanillic acid concentration in normal subjects.

    PubMed

    Zemishlany, Z; Davidson, M

    1996-08-15

    The present study was undertaken to investigate if acute anxiety can affect plasma concentrations of homovanillic acid (pHVA). Since elevated pHVA levels have been associated with severity of schizophrenic symptoms, the results of this study will help determine if the pHVA elevations are directly related to psychosis or if anxiety is also a contributory factor. Anxiety was provoked in 10 young normal subjects by a combined paradigm of mental arithmetic task and threat of electrical shock. A significant increase in self-ratings of anxiety, blood pressure, and plasma levels of norepinephrine, 3-methoxy-4-hydroxyphenylethyleneglycol and growth hormone indicated that the paradigm used was effective in provoking anxiety; however, anxiety did not affect pHVA concentrations. The results may support the notion that increased pHVA levels in severely ill schizophrenic patients are related to the schizophrenic pathophysiology rather than to anxiety.

  19. Plasma homovanillic acid in schizophrenics: supportive evidence for the two-subtype hypothesis.

    PubMed

    Chen, T Y; Lee, C F; Lung, F W; Lee, T C; Lin, W L; Hu, W H; Yeh, E K; Chang, W H

    1989-06-01

    Plasma levels of homovanillic acid (pHVA), a major metabolite of dopamine (DA), were measured in a group of 51 schizophrenic inpatients before and during 6 weeks of neuroleptic treatment. Steady-state plasma drug concentrations were monitored in parallel with pHVA. Good responders (n = 22) had higher pretreatment pHVA levels as compared to poor responders (n = 22). Differential pHVA changes during neuroleptic treatment were also found between each group. The two groups did not differ significantly in terms of age, duration of illness, severity of presenting symptoms, neuroleptic, dose, or plasma drug concentration. Two hypothetical subtypes in the group of schizophrenics were proposed.

  20. The effect of hip positioning on the projected femoral neck-shaft angle: a modeling study.

    PubMed

    Bhashyam, Abhiram R; Rodriguez, Edward K; Appleton, Paul; Wixted, John J

    2018-04-03

    The femoral neck-shaft angle (NSA) is used to restore normal hip geometry during hip fracture repair. Femoral rotation is known to affect NSA measurement, but the effect of hip flexion-extension is unknown. The goals of this study were to determine and test mathematical models of the relationship between hip flexion-extension, femoral rotation and NSA. We hypothesized that hip flexion-extension and femoral rotation would result in NSA measurement error. Two mathematical models were developed to predict NSA in varying degrees of hip flexion-extension and femoral rotation. The predictions of the equations were tested in vitro using a model that varied hip flexion-extension while keeping rotation constant, and vice versa. The NSA was measured from an AP radiograph obtained with a C-arm. Attributable measurement error based on hip positioning was calculated from the models. The predictions of the model correlated well with the experimental data (correlation coefficient = 0.82 - 0.90). A wide range of patient positioning was found to result in less than 5-10 degree error in the measurement of NSA. Hip flexion-extension and femoral rotation had a synergistic effect in measurement error of the NSA. Measurement error was minimized when hip flexion-extension was within 10 degrees of neutral. This study demonstrates that hip flexion-extension and femoral rotation significantly affect the measurement of the NSA. To avoid inadvertently fixing the proximal femur in varus or valgus, the hip should be positioned within 10 degrees of neutral flexion-extension with respect to the C-arm to minimize positional measurement error. N/A, basic science study.

  1. Plasma homovanillic acid differences in clinical subgroups of first episode schizophrenic patients.

    PubMed

    Baeza, Immaculada; Castro-Fornieles, Josefina; Deulofeu, Ramon; de la Serna, Elena; Goti, Javier; Salvà, Joan; Bernardo, Miquel

    2009-07-30

    This study evaluates the relationship between plasma homovanillic acid (pHVA) levels, which have been used to study the role of central dopamine in schizophrenia, and the positive/negative syndrome in first episode schizophrenic patients before and after antipsychotic treatment. Forty neuroleptic-naive first episode schizophrenic patients were monitored at baseline and on days 7, 14 and 28. Clinical status was evaluated with the Scale for the Assessment of Positive Symptoms (SAPS), the Scale for the Assessment of Negative Symptoms (SANS), and the Brief Psychotic Rating Scale. Plasma HVA levels were also measured. Patients were divided into predominantly positive or negative syndrome groups by subtracting SAPS from SANS scores, at baseline. A healthy control group was also enrolled. Schizophrenic patients as a group had significantly higher pHVA levels than controls at baseline (20.50+/-11.85 vs. 13.04+/-7.22 ng/ml). Moreover, 12 predominantly negative syndrome patients had similar mean baseline pHVA levels (21.30+/-12.36 ng/ml) to those of 28 predominantly positive syndrome patients (19.40+/-11.33 ng/ml). During follow-up, there was a different evolution of pHVA levels in the predominantly positive syndrome group than in the predominantly negative syndrome group, with a significantly greater global reduction of pHVA levels in the former. Although both groups showed clinical improvement following 4 weeks of treatment with risperidone, pHVA levels at endpoint were lower (13.29+/-5.91 ng/ml) than at baseline in patients in the predominantly positive syndrome group, while among those in the predominantly negative syndrome group there was no difference in pHVA levels before and after treatment (21.02+/-13.06 ng/ml). The different pHVA level profiles observed in predominantly positive and negative syndrome first episode patients after 4 weeks of treatment with risperidone suggest that each syndrome may have a different underlying neurobiology.

  2. Behavior of Tilted Angle Shear Connectors.

    PubMed

    Khorramian, Koosha; Maleki, Shervin; Shariati, Mahdi; Ramli Sulong, N H

    2015-01-01

    According to recent researches, angle shear connectors are appropriate to transfer longitudinal shear forces across the steel-concrete interface. Angle steel profile has been used in different positions as L-shaped or C-shaped shear connectors. The application of angle shear connectors in tilted positions is of interest in this study. This study investigates the behaviour of tilted-shaped angle shear connectors under monotonic loading using experimental push out tests. Eight push-out specimens are tested to investigate the effects of different angle parameters on the ultimate load capacity of connectors. Two different tilted angles of 112.5 and 135 degrees between the angle leg and steel beam are considered. In addition, angle sizes and lengths are varied. Two different failure modes were observed consisting of concrete crushing-splitting and connector fracture. By increasing the size of connector, the maximum load increased for most cases. In general, the 135 degrees tilted angle shear connectors have a higher strength and stiffness than the 112.5 degrees type.

  3. Hepatoprotective and immunological functions of Nigella sativa seed oil against hypervitaminosis A in adult male rats.

    PubMed

    Al-Suhaimi, Ebtesam Abdullah

    2012-08-01

    The toxic effects of excess vitamin A (VA) intake deserve increased attention. Nigella sativa (NS) seed possesses physiological and pharmacological actions and protects against toxic agents. This work investigated the availability of NS seed oil as a protective agent against the effects of hypervitaminosis A (HVA) on liver function and immunity. Fifty adult albino rats were used and divided into five groups: (G1) control; (G2) experimental HVA rats administered extreme doses (10,000 IU/kg body weight) of VA oil orally, daily for 6 weeks; (G3) rats treated with NS seed oil (800 mg/kg) orally, daily for 6 weeks; (G4) HVA rats simultaneously treated with NS seed oil at the same doses and periods; and (G5) HVA recovery group. Liver function, immunoglobulin (IgG and IgM) levels, and lysosome activity were measured in serum. HVA rats revealed marked elevations in alanine aminotransferase and aspartate aminotransferase activities. This is the first study to demonstrate that NS seed oil possesses significant hepatoprotective activity against HVA. NS seed oil was a potent inducer of IgG and IgM in rat serum either alone or with high doses of VA. These findings may be considered the initial steps of the physiological and humoral immune responses for NS seed oil against HVA, but further studies examining longer periods are needed prior to recommending the use of NS seed oil as an alternative medicine for hepatic and immune diseases.

  4. Variability of plasma homovanillic acid over 13 months in patients with schizophrenia; relationship with the clinical response and the Wisconsin card sort test.

    PubMed

    Zumárraga, Mercedes; González-Torres, Miguel A; Arrue, Aurora; Dávila, Ricardo; Dávila, Wendy; Inchausti, Lucía; Pérez-Cabeza, Lucía; Fernández-Rivas, Aránzazu; Bustamante, Sonia; Basterreche, Nieves; Guimón, José

    2011-08-01

    In the present study we have measured, on a monthly basis, the concentration of plasma homovanillic acid (pHVA) in schizophrenic patients during 13 months of their pharmacological treatment. The average pHVA values of each patient were within the range of 7.30-17.70 ng/ml and the coefficients of variation for each patient (CV %) were within the range of 13-33%. Half of the patients that showed higher pHVA CV% values also showed higher scores on the Brief Psychiatric Rating Scale at the beginning of the study, and improved more after 6 months, when compared to the remaining 50% with lower CV% values. There was no significant relationship between the scores of the Wisconsin Card Sort Test and the concentration or the CV% of the pHVA of each patient. A greater variability in the pHVA may be associated with a greater plasticity of the dopaminergic system and a better clinical response.

  5. Growth Angle - a Microscopic View

    NASA Technical Reports Server (NTRS)

    Mazurak, K.; Volz, M. P.; Croll, A.

    2017-01-01

    The growth angle that is formed between the side of the growing crystal and the melt meniscus is an important parameter in the detached Bridgman crystal growth method, where it determines the extent of the crystal-crucible wall gap, and in the Czochralski and float zone methods, where it influences the size and stability of the crystals. The growth angle is a non-equilibrium parameter, defined for the crystal growth process only. For a melt-crystal interface translating towards the crystal (melting), there is no specific angle defined between the melt and the sidewall of the solid. In this case, the corner at the triple line becomes rounded, and the angle between the sidewall and the incipience of meniscus can take a number of values, depending on the position of the triple line. In this work, a microscopic model is developed in which the fluid interacts with the solid surface through long range van der Waals or Casimir dispersive forces. This growth angle model is applied to Si and Ge and compared with the macroscopic approach of Herring. In the limit of a rounded corner with a large radius of curvature, the wetting of the melt on the crystal is defined by the contact angle. The proposed microscopic approach addresses the interesting issue of the transition from a contact angle to a growth angle as the radius of curvature decreases.

  6. [The minimally invasive Chevron and Akin osteotomy (MICA)].

    PubMed

    Altenberger, Sebastian; Kriegelstein, Stefanie; Gottschalk, Oliver; Dreyer, Florian; Mehlhorn, Alexander; Röser, Anke; Walther, Markus

    2018-04-18

    Percutaneous correction of a hallux valgus deformity with or without transfer metatarsalgia. Hallux valgus deformity up to 20° intermetatarsal angle, without instability of the first tarsometatarsal joint. Symptomatic arthritis of the first metatarsophalangeal joint, as well as instability of the first tarsometatarsal joint. Percutaneous performed osteotomy of the distal metatarsal 1 in combination with a medial closing wedge osteotomy of the proximal phalanx of the first toe. The use of a postoperative shoe with a rigid sole allows adapted weight bearing in the first 6 weeks. Active and passive mobilization can start immediately after surgery. The method is very effective to treat even severe deformities with or without metatarsalgia. The amount of correction is similar to open procedures. We recommend cadaver training to become familiar with this technique. Thus, complications such as nerve, vessel or tendon injuries can be avoided. The intraoperative radiation exposure remains significantly elevated even for experienced surgeons. In addition to the aesthetic benefits, there is less soft tissue traumatization compared to conventional open procedures. There is no need of bloodlessness. The minimally invasive Chevron and Akin osteotomy is a safe and powerful technique for the treatment of hallux valgus deformity.

  7. Behavior of Tilted Angle Shear Connectors

    PubMed Central

    Khorramian, Koosha; Maleki, Shervin; Shariati, Mahdi; Ramli Sulong, N. H.

    2015-01-01

    According to recent researches, angle shear connectors are appropriate to transfer longitudinal shear forces across the steel-concrete interface. Angle steel profile has been used in different positions as L-shaped or C-shaped shear connectors. The application of angle shear connectors in tilted positions is of interest in this study. This study investigates the behaviour of tilted-shaped angle shear connectors under monotonic loading using experimental push out tests. Eight push-out specimens are tested to investigate the effects of different angle parameters on the ultimate load capacity of connectors. Two different tilted angles of 112.5 and 135 degrees between the angle leg and steel beam are considered. In addition, angle sizes and lengths are varied. Two different failure modes were observed consisting of concrete crushing-splitting and connector fracture. By increasing the size of connector, the maximum load increased for most cases. In general, the 135 degrees tilted angle shear connectors have a higher strength and stiffness than the 112.5 degrees type. PMID:26642193

  8. Two-dimensional planning can result in internal rotation of the femoral component in total knee arthroplasty.

    PubMed

    Okamoto, Shigetoshi; Mizu-uchi, Hideki; Okazaki, Ken; Hamai, Satoshi; Tashiro, Yasutaka; Nakahara, Hiroyuki; Iwamoto, Yukihide

    2016-01-01

    The first purpose of this study was to compare the reproducibility of two-dimensional (2D) and three-dimensional (3D) measurements for preoperative planning of the femoral side in total knee arthroplasty (TKA). The second purpose was to evaluate the factors affecting the differences between the 2D and 3D measurements. Two-dimensional and 3D measurements for preoperative planning of the femoral side in TKA were evaluated in 75 varus knees with osteoarthritis. The femoral valgus angle, defined as the angle between the mechanical and anatomical axes of the femur, and the clinical rotation angle and surgical rotation angle, defined by the angles between the posterior condylar line and the clinical or surgical transepicondylar axes, respectively, were analysed using 2D (radiographs and axial CT slices) and 3D (3D bone models reconstructed from CT images) measurements. For all variables, 3D measurements were more reliable and reproducible than 2D measurements. The medians and ranges of the clinical rotation angle and surgical rotation angle were 6.6° (-1.7° to 12.1°) and 2.3° (-2.5° to 8.6°) in 2D, and 7.1° (2.7° to 11.4°) and 3.0° (-2.0° to 7.5°) in 3D. Varus/valgus alteration of the CT scanning direction relative to the mechanical axis affected the difference in clinical rotation angles between 2D and 3D measurements. Significantly, smaller values of the clinical rotation angle and surgical rotation angle were obtained by 2D compared to 3D measurements, which could result in internal rotation of the femoral component even if the surgeon performs the bone cutting precisely. Regarding clinical relevance, first, this study confirmed the reliability of 3D measurements. Second, it underscored the risk of internal rotation of the femoral component when using 2D measurement, even with precise bone cutting technique. These results will help surgeons avoid malpositioning of the femoral component if 2D measurements are used for preoperative planning in TKA

  9. Radiologic changes of ankle joint after total knee arthroplasty.

    PubMed

    Lee, Jung Hee; Jeong, Bi O

    2012-12-01

    The authors noticed that ankle joint osteoarthritis was not uncommon when lower extremity malalignment, such as a knee varus deformity, was present as a result of severe osteoarthritis of the knee. The purpose of this study was to analyze radiologic changes of the ankle joint after total knee arthroplasty. This study included 142 cases in 110 patients who underwent total knee arthroplasty and were followed for at least 3 years. The varus knee group included 128 cases and the valgus knee group included 14 cases. On anteroposterior standing lower extremity radiographs, varus and valgus angles of the knee were measured preoperatively and at the last follow-up. The angle between the ground surface and the distal tibial plafond as well as the upper talus was also measured. In addition, tibial anterior surface angle, talar tilt, space between the medial malleolar distal tip and the medial articular surface of the talus, and medial tibiotalar joint space of the ankle joint were measured. Out of 142 cases, 50 (35.2%) had arthritis in the ankle before total knee arthroplasty and 31 (21.8%) had newly developed or progressive arthritis after surgery. In particular, the varus knee group demonstrated statistically significant differences in preoperative varus deformity, preoperative talar tilt, and postoperative correction angle between the cases that developed or had progressive arthritis and those that did not show any changes (p < .05). After total knee arthroplasty, arthritis developed or progressed in the ankle of many cases radiographically. In particular, when the preoperative talar tilt increased medial to the ankle or the postoperative correction angle was large, the incidence of arthritis in the ankle joint increased. The authors recommend more cautious follow-up on the symptoms of the ankle joint after total knee arthroplasty.

  10. View angle effect in LANDSAT imagery

    NASA Technical Reports Server (NTRS)

    Kaneko, T.; Engvall, J. L.

    1977-01-01

    The view angle effect in LANDSAT 2 imagery was investigated. The LANDSAT multispectral scanner scans over a range of view angles of -5.78 to 5.78 degrees. The view angle effect, which is caused by differing view angles, could be studied by comparing data collected at different view angles over a fixed location at a fixed time. Since such LANDSAT data is not available, consecutive day acquisition data were used as a substitute: they were collected over the same geographical location, acquired 24 hours apart, with a view angle change of 7 to 8 degrees at a latitude of 35 to 45 degrees. It is shown that there is approximately a 5% reduction in the average sensor response on the second-day acquisitions as compared with the first-day acquisitions, and that the view angle effect differs field to field and crop to crop. On false infrared color pictures the view angle effect causes changes primarily in brightness and to a lesser degree in color (hue and saturation). An implication is that caution must be taken when images with different view angles are combined for classification and a signature extension technique needs to take the view angle effect into account.

  11. Demonstration of angle widening using EyeCam after laser peripheral iridotomy in eyes with angle closure.

    PubMed

    Perera, Shamira A; Quek, Desmond T; Baskaran, Mani; Tun, Tin A; Kumar, Rajesh S; Friedman, David S; Aung, Tin

    2010-06-01

    To evaluate EyeCam in detecting changes in angle configuration after laser peripheral iridotomy (LPI) in comparison to gonioscopy, the reference standard. Prospective comparative study. Twenty-four subjects (24 eyes) with primary angle-closure glaucoma (PACG) were recruited. Gonioscopy and EyeCam (Clarity Medical Systems) imaging of all 4 angle quadrants were performed, before and 2 weeks after LPI. Images were graded according to angle structures visible by an observer masked to clinical data or the status of LPI, and were performed in a random order. Angle closure in a quadrant was defined as the inability to visualize the posterior trabecular meshwork. We determined the number of quadrants with closed angles and the mean number of clock hours of angle closure before and after LPI in comparison to gonioscopy. Using EyeCam, all 24 eyes showed at least 1 quadrant of angle widening after LPI. The mean number of clock hours of angle closure decreased significantly, from 8.15 +/- 3.47 clock hours before LPI to 1.75 +/- 2.27 clock hours after LPI (P < .0001, Wilcoxon signed rank test). Overall, gonioscopy showed 1.0 +/- 1.41 (95% CI, 0.43-1.57) quadrants opening from closed to open after LPI compared to 2.0 +/- 1.28 (95% CI, 1.49-2.51, P = .009) quadrants with EyeCam. Intra-observer reproducibility of grading the extent of angle closure in clock hours in EyeCam images was moderate to good (intraclass correlation coefficient 0.831). EyeCam may be used to document changes in angle configuration after LPI in eyes with PACG. Copyright 2010 Elsevier Inc. All rights reserved.

  12. Dietary flavonols contribute to false-positive elevation of homovanillic acid, a marker of catecholamine-secreting tumors.

    PubMed

    Combet, Emilie; Lean, Michael E J; Boyle, James G; Crozier, Alan; Davidson, D Fraser

    2011-01-14

    Urinary homovanillic acid (HVA) measurement is used routinely as a marker of the first test for the screening of catecholamine-secreting tumors and dopamine metabolism, but generates a large number of false-positive results. With no guidelines for dietary restrictions prior to the test, we hypothesize that consumption of flavonol-rich foods (such as onions, tomatoes, tea) prior to urinary catecholamine screening could be responsible for false-positive urinary HVA in healthy subjects. A randomized, crossover dietary intervention was carried out in healthy subjects (n=17). Volunteers followed either a low or high-flavonol diet, for a duration of 3 days, prior to providing a 24-h urine sample for HVA measurement using a routine, validated liquid chromatography method as well as a gas chromatography-mass spectrometry method. Dietary flavonol intake significantly increased urinary HVA excretion (p < 0.001), with 3 out of 17 volunteers (20%) exceeding the 40 μmol/24 h upper limit of normal for HVA excretion (false-positive result). Dietary flavonols commonly found in foodstuff such as tomatoes, onions, and tea, interfered with the routine urinary HVA screening test and should be avoided in the three-day run-up to the test. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Plasma homovanillic acid in adolescents with bulimia nervosa.

    PubMed

    Castro-Fornieles, Josefina; Deulofeu, Ramón; Martínez-Mallen, Esteve; Baeza, Immaculada; Fernández, Lorena; Lázaro, Luisa; Toro, Josep; Vila, Montserrat; Bernardo, Miquel

    2009-12-30

    Dopaminergic abnormalities in bulimia nervosa have been reported in some studies, but results are not consistent across studies. In the present study, clinical characteristics, plasma level of homovanillic acid (pHVA) and two scales - the Eating Attitudes Test (EAT) and the Beck Depression Inventory (BDI) - were assessed in 36 adolescent bulimia nervosa patients (mean age16.3 years, S.D. 1.1) who were consecutively seen on an Eating Disorder Unit. Levels of pHVA were also measured in 16 healthy control adolescents from the general population. Patients had significantly higher mean pHVA than controls. Eighteen patients (50%) had a pHVA level equal to or higher than the mean of control subjects plus one standard deviation, and this group of patients had significantly higher mean BDI scores and non-significantly higher mean EAT scores, although they did not differ from the other patients in age, time elapsed since the onset of disorder, body mass index and number of binges or vomits. Moreover, in logistic regression analysis the BDI score proved to be an independent predictor of high pHVA. The level of pHVA is increased in bulimia nervosa patients with high scores on measures of depressive and eating symptomatology.

  14. Effect of switching to risperidone after unsuccessful treatment with aripiprazole on plasma monoamine metabolites level in the treatment of acute schizophrenia.

    PubMed

    Miura, Itaru; Takeuchi, Satoshi; Katsumi, Akihiko; Kanno, Keiko; Watanabe, Kenya; Mashiko, Hirobumi; Niwa, Shin-Ichi

    2012-09-01

    In the treatment of acute schizophrenia, risperidone and aripiprazole are both placed the first line antipsychotics. These two antipsychotics have different pharmacological effects. We investigated the effects of risperidone on plasma levels of homovanillic acid (HVA) and 3-methoxy-4hydroxyphenylglycol after unsuccessful aripiprazole treatment in acute schizophrenia. Ten Japanese patients with acute schizophrenia were enrolled to this study. Plasma levels of monoamine metabolites were analyzed with high-performance liquid chromatography with electrochemical detection. Risperidone improved the symptoms and 4 of 10 patients were responders. Risperidone showed a tendency to decrease plasma HVA (pHVA) levels in responders (p = 0.068), but not in non-responders (p = 1.0). At baseline, pHVA levels of responders were significantly higher than that of non-responders (p = 0.033). A trend for negative correlation was found between pHVA at baseline and the changes in Positive and Negative Syndrome Scale-Total (p = 0.061, r = -0.61). Our results suggest that high pHVA level before switching may predict good response to the second line antipsychotics after unsuccessful first antipsychotic treatment. If aripiprazole is not effective in acute schizophrenia, switching to risperidone may be effective and reasonable strategy for improving symptoms. Copyright © 2012 John Wiley & Sons, Ltd.

  15. Bilateral mandibular angle fractures: clinical considerations.

    PubMed

    Boffano, Paolo; Roccia, Fabio

    2010-03-01

    The mandibular angle is a frequent site of fracture. It is a weak zone that is more exposed to fractures than other areas of the mandibular bone. The presence of incompletely erupted third molars is associated with a further increased risk of angle fractures. Our objective was to evaluate and discuss the surgical outcomes of a group of patients with bilateral mandibular angle fractures.In our study, patients with bilateral mandibular angle fractures surgically treated from January 1, 2001, to June 30, 2009, at the Division of Maxillofacial Surgery of the University of Turin were retrospectively analyzed. A combined transbuccal and intraoral approach or an intraoral approach only was adopted.Eight patients (7 men and 1 woman) underwent surgery for bilateral mandibular angle fractures. Good to satisfactory reduction of the fractures was obtained with both surgical techniques. Good to fair restored occlusion was observed postoperatively in all patients.Successful treatment of bilateral mandibular angle fractures may be achieved via different techniques. Superficially impacted third molars seem to be associated with an increased risk of angle fractures. Bilateral angle fractures are an ideal model to study the biomechanical pathogenesis of angle fractures.

  16. Greater Hip Extension but Not Hip Abduction Explosive Strength Is Associated With Lesser Hip Adduction and Knee Valgus Motion During a Single-Leg Jump-Cut

    PubMed Central

    Cronin, Baker; Johnson, Samuel T.; Chang, Eunwook; Pollard, Christine D.; Norcross, Marc F.

    2016-01-01

    Background: The relationships between hip abductor and extensor strength and frontal plane hip and knee motions that are associated with anterior cruciate ligament injury risk are equivocal. However, previous research on these relationships has evaluated relatively low-level movement tasks and peak torque rather than a time-critical strength measure such as the rate of torque development (RTD). Hypothesis: Females with greater hip abduction and extension RTD would exhibit lesser frontal plane hip and knee motion during a single-leg jump-cutting task. Study Design: Descriptive laboratory study. Methods: Forty recreationally active females performed maximal isometric contractions and single-leg jump-cuts. From recorded torque data, hip extension and abduction RTD was calculated from torque onset to 200 ms after onset. Three-dimensional motion analysis was used to quantify frontal plane hip and knee kinematics during the movement task. For each RTD measure, jump-cut biomechanics were compared between participants in the highest (high) and lowest (low) RTD tertiles. Results: No differences in frontal plane hip and knee kinematics were identified between high and low hip abduction RTD groups. However, those in the high hip extension RTD group exhibited lower hip adduction (high, 3.8° ± 3.0°; low, 6.5° ± 3.0°; P = .019) and knee valgus (high, –2.5° ± 2.3°; low, –4.4° ± 3.2°; P = .046) displacements during the jump-cut. Conclusion: In movements such as cutting that are performed with the hip in a relatively abducted and flexed position, the ability of the gluteus medius to control hip adduction may be compromised. However, the gluteus maximus, functioning as a hip abductor, may take on a pivotal role in controlling hip adduction and knee valgus motion during these types of tasks. Clinical Relevance: Training with a specific emphasis on increasing explosive strength of the hip extensors may be a means through which to improve frontal plane hip and knee

  17. Reading angles in maps.

    PubMed

    Izard, Véronique; O'Donnell, Evan; Spelke, Elizabeth S

    2014-01-01

    Preschool children can navigate by simple geometric maps of the environment, but the nature of the geometric relations they use in map reading remains unclear. Here, children were tested specifically on their sensitivity to angle. Forty-eight children (age 47:15-53:30 months) were presented with fragments of geometric maps, in which angle sections appeared without any relevant length or distance information. Children were able to read these map fragments and compare two-dimensional to three-dimensional angles. However, this ability appeared both variable and fragile among the youngest children of the sample. These findings suggest that 4-year-old children begin to form an abstract concept of angle that applies both to two-dimensional and three-dimensional displays and that serves to interpret novel spatial symbols. © 2013 The Authors. Child Development © 2013 Society for Research in Child Development, Inc.

  18. Anterior Segment Imaging for Angle Closure.

    PubMed

    Chansangpetch, Sunee; Rojanapongpun, Prin; Lin, Shan C

    2018-04-01

    To summarize the role of anterior segment imaging (AS-imaging) in angle closure diagnosis and management, and the possible advantages over the current standard of gonioscopy. Literature review and perspective. Review of the pertinent publications with interpretation and perspective in relation to the use of AS-imaging in angle closure assessment focusing on anterior segment optical coherence tomography and ultrasound biomicroscopy. Several limitations have been encountered with the reference standard of gonioscopy for angle assessment. AS-imaging has been shown to have performance in angle closure detection compared to gonioscopy. Also, imaging has greater reproducibility and serves as better documentation for long-term follow-up than conventional gonioscopy. The qualitative and quantitative information obtained from AS-imaging enables better understanding of the underlying mechanisms of angle closure and provides useful parameters for risk assessment and possible prediction of the response to laser and surgical intervention. The latest technologies-including 3-dimensional imaging-have allowed for the assessment of the angle that simulates the gonioscopic view. These advantages suggest that AS-imaging has a potential to be a reference standard for the diagnosis and monitoring of angle closure disease in the future. Although gonioscopy remains the primary method of angle assessment, AS-imaging has an increasing role in angle closure screening and management. The test should be integrated into clinical practice as an adjunctive tool for angle assessment. It is arguable that AS-imaging should be considered first-line screening for patients at risk for angle closure. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Selective decrease in central nervous system serotonin turnover in children with dopa-nonresponsive dystonia.

    PubMed

    Assmann, Birgit; Köhler, Martin; Hoffmann, Georg F; Heales, Simon; Surtees, Robert

    2002-07-01

    Childhood dystonia that does not respond to treatment with levodopa (dopa-nonresponsive dystonia, DND) has an unclear pathogenesis and is notoriously difficult to treat. To test the hypothesis that there may be abnormalities in serotonin turnover in DND we measured cerebrospinal fluid (CSF) concentrations of homovanillic (HVA) and 5-hydroxyindoleacetic (HIAA) acids, metabolites of dopamine and serotonin, respectively, in 18 children with dystonia not responsive to levodopa. These were combined with a reference population of 85 children with neurologic or metabolic disease known not to affect dopamine or serotonin metabolism. Because of the known natural age-related decrement in HVA and HIAA concentrations, the results were analyzed using multiple regression using age and DND as predictors of CSF HIAA and HVA concentrations. DND was a highly significant predictor of CSF HIAA concentration (p < 0.001) but not of CSF HVA concentration (p = 0.59). After fitting a regression model, the geometric mean ratio of CSF HIAA in DND compared with the reference range was 0.53 whereas that for CSF HVA was 0.95. We also analyzed CSF HIAA/HVA ratios. After fitting a regression model, we found no dependence on age, and the mean of CSF HIAA/HVA in DND was 0.28 whereas that for the reference range was 0.49 (p < 0.001). We conclude that a significant number of children with DND have reduced CNS serotonin turnover. Treatment with drugs that increase serotonin concentration in the synaptic cleft should be considered in this group of patients.

  20. Angle-Ply Weaving

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1990-01-01

    Bias-direction or angle-ply weaving is proposed new process for weaving fibers along bias in conventional planar fabric or in complicated three-dimensional multilayer fabric preform of fiber-reinforced composite structure. Based upon movement of racks of needles and corresponding angle yarns across fabric as fabric being formed. Fibers woven along bias increases shear stiffness and shear strength of preform, increasing value of preform as structural member.

  1. Medial-to-lateral Ratio of Tibiofemoral Subchondral Bone Area is Adapted to Alignment and Mechanical Load

    PubMed Central

    Eckstein, Felix; Hudelmaier, Martin; Cahue, September; Marshall, Meredith; Sharma, Leena

    2010-01-01

    Malalignment is known to impact the medial-to-lateral load distribution in the tibiofemoral joint. In this longitudinal study, we test the hypothesis that subchondral bone surface areas functionally adapt to the load distribution in malaligned knees. Alignment (hip-knee-ankle angle) was measured from full limb films in 174 participants with knee osteoarthritis. Coronal MR images were acquired at baseline and 26.6±5.4 months later. The subchondral bone surface area of the weight-bearing tibiofemoral cartilages was segmented, with readers blinded to the order of acquisition. The size of the subchondral bone surface areas was computed after triangulation using proprietary software. The hip-knee-ankle angle showed a significant correlation with the tibial (r2=0.25, p<0.0001) and femoral (r2=0.07, p<0.001) ratio of medial-to-lateral subchondral bone surface area. In the tibia, the ratio was significantly different between varus (1.28:1), neutral (1.18:1) and valgus (1.13:1) knees (ANOVA; p<0.00001). Similar observations were made in the weight-bearing femur (0.94:1 in neutral, 0.97.1 in varus, 0.91:1 in valgus knees; ANOVA p=0.018). The annualized longitudinal increase in subchondral bone surface area was significant (p<0.05) in the medial tibia (+0.13%), medial femur (+0.26%) and lateral tibia (+0.19%). In the medial femur, the change between baseline and follow-up was significantly different (ANOVA; p=0.020) between neutral, varus and valgus knees, the increase in surface area being significantly greater (p=0.019) in varus than in neutral knees. Tibiofemoral subchondral bone surface areas are shown to be functionally adapted to the medial-to-lateral load distribution. The longitudinal findings indicate that this adaptational process may continue to take place at advanced age. PMID:19148562

  2. Wafer scale oblique angle plasma etching

    DOEpatents

    Burckel, David Bruce; Jarecki, Jr., Robert L.; Finnegan, Patrick Sean

    2017-05-23

    Wafer scale oblique angle etching of a semiconductor substrate is performed in a conventional plasma etch chamber by using a fixture that supports a multiple number of separate Faraday cages. Each cage is formed to include an angled grid surface and is positioned such that it will be positioned over a separate one of the die locations on the wafer surface when the fixture is placed over the wafer. The presence of the Faraday cages influences the local electric field surrounding each wafer die, re-shaping the local field to be disposed in alignment with the angled grid surface. The re-shaped plasma causes the reactive ions to follow a linear trajectory through the plasma sheath and angled grid surface, ultimately impinging the wafer surface at an angle. The selected geometry of the Faraday cage angled grid surface thus determines the angle at with the reactive ions will impinge the wafer.

  3. Spinning angle optical calibration apparatus

    DOEpatents

    Beer, Stephen K.; Pratt, II, Harold R.

    1991-01-01

    An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting an accurate reproducing of spinning "magic angles" in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the "magic angle" of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation or graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning "magic angle" of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position.

  4. Brief debrisoquin administration to assess central dopaminergic function in children.

    PubMed

    Riddle, M A; Shaywitz, B A; Leckman, J F; Anderson, G M; Shaywitz, S E; Hardin, M T; Ort, S I; Cohen, D J

    1986-03-17

    Central dopaminergic (DA) function in children was assessed by monitoring plasma-free homovanillic acid (pHVA) levels after brief (18 hour) administration with debrisoquin sulfate, a peripherally active antihypertensive agent that blocks peripheral, but not central, HVA production. Brief debrisoquin administration resulted in marked reductions in pHVA in each of six patients studied. In five of the six patients, post-debrisoquin pHVA levels remained relatively stable over the six-hour period of observation. No significant cardiovascular or behavioral side effects of debrisoquin were observed. The brief debrisoquin administration method appears to be a safe, simple, and potentially valid peripheral technique for evaluating aspects of central dopaminergic function in children with neuropsychiatric disorders. Additional work is needed to further establish this method's validity and reliability.

  5. Plasma homovanillic acid, plasma anti-D1 and -D2 dopamine-receptor activity, and negative symptoms in chronically mediated schizophrenia.

    PubMed

    Suzuki, E; Kanba, S; Nibuya, M; Koshikawa, H; Nakaki, T; Yagi, G

    1992-02-15

    We have investigated the relationship between the concentration of homovanillic acid in human plasma (pHVA) and plasma anti-D1 and anti-D2 dopamine receptor activity in chronic schizophrenic patients whose neuroleptic dosage was changed. The change in pHVA level correlated with that in anti-D1, not anti-D2 activity, thus suggesting that the neuroleptic-induced changes in pHVA concentration may be associated with the blocking of D1- as well as D2- receptors. The change of scores on the Scale for the Assessment of Negative Symptoms did not significantly correlate with changes in anti-D1 or anti-D2 activity, but did so correlated with the change in pHVA level.

  6. Plasma prolactin and homovanillic acid as markers for psychopathology and abnormal movements after neuroleptic dose decrease.

    PubMed

    Newcomer, J W; Riney, S J; Vinogradov, S; Csernansky, J G

    1992-01-01

    Plasma prolactin concentration (pPRL), plasma homovanillic acid concentration (pHVA), and symptomatology were measured in 24 male subjects with schizophrenia during maintenance haloperidol treatment. Fourteen subjects subsequently underwent 50 percent dose decreases under placebo-controlled, double-blind conditions. At baseline, a significant inverse correlation was found between pPRL and both tardive dyskinesia (TD) and "thinking disorder"; pPRL was directly correlated with negative symptoms. No such relationship was found with pHVA. In the patients who underwent a dose decrease, no relationship was found between baseline pPRL or pHVA and any clinical variable after the decrease. These data do not support the use of baseline pPRL or pHVA as markers of central dopamine function subsequent to a neuroleptic dose decrease.

  7. Increments in plasma homovanillic acid concentrations after neuroleptic discontinuation are associated with worsening of schizophrenic symptoms.

    PubMed

    Khan, R S; Amin, F; Powchik, P; Knott, P; Goldstein, M; Apter, S; Kerman, B; Jaff, S; Davidson, M

    1990-01-01

    1. Thirty-two male schizophrenic patients participated in this study. 2. Plasma concentrations of the dopamine metabolite, homovanillic acid (pHVA) were assessed once on neuroleptic medication and twice a week for a maximum of six weeks after its discontinuation. 3. Psychiatric symptomatology was assessed once on neuroleptic medication and once a week for a maximum of six weeks after its discontinuation, using the brief psychiatric rating scale (BPRS). 4. pHVA and total BPRS score increased significantly after discontinuation of neuroleptic as compared to baseline. 5. The magnitude of pHVA and BPRS increments after discontinuation of neuroleptic correlated significantly. 6. Results of this study suggest that worsening of schizophrenic symptoms after discontinuation of neuroleptic treatment is associated with increased pHVA concentrations.

  8. Chevron closing base wedge bunionectomy.

    PubMed

    Bruyn, J M

    1993-01-01

    The Chevron-base wedge Association for Osteosynthesis fixated bunionectomy provides a stable, aggressive correction of the severe hallux abducto valgus deformity. It is intended for the bunion requiring a double osteotomy in order to adequately reduce both intermetatarsal and proximal articular facet angle with minimal shortening and elevation. This article presents the rationale for the procedure, technique, and a 4-year follow-up of six patients with eight Chevron-base wedge bunionectomies.

  9. Spinning angle optical calibration apparatus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beer, S.K.; Pratt, H.R. II.

    1989-09-12

    An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting and accurate reproducing of spinning magic angles in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the magic angle of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation ormore » graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning magic angle of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position. 2 figs.« less

  10. Growth Angle: A Microscopic View

    NASA Technical Reports Server (NTRS)

    Mazuruk, Konstantin; Croll, Arne; Volz, Martin P.

    2017-01-01

    A microscopic continuum mechanical model of the growth angle is proposed. It is based on the van der Waals type framework that is used for surface force phenomena. The obtained augmented Laplace type integro-differential equations are, in general, difficult to analyze. Here we focused primarily on the particular case of equal melt and crystal surface energies. We derived an approximate equation for the meniscus shape, and obtained an analytical relationship between the contact and the growth angle. Interestingly, the same result can be obtained using the macroscopic model of Herring. The case of a macroscopically sharp corner is also considered. For this case, the macroscopic angle is not defined and it can be any angle between the contact angles of both flat surfaces. The microscopic model yields the smooth shape for the meniscus that also is not unique, but depends on the initial position of the meniscus.

  11. Plasma homovanillic acid levels and therapeutic outcome in schizophrenics: comparisons of neuroleptic-naive first-episode patients and patients with disease exacerbation due to neuroleptic discontinuance.

    PubMed

    Akiyama, K; Tsuchida, K; Kanzaki, A; Ujike, H; Hamamura, T; Kondo, K; Mutoh, S; Miyanagi, K; Kuroda, S; Otsuki, S

    1995-11-15

    Plasma homovanillic acid (pHVA) levels were measured and the Brief Psychiatric Rating Scale (BPRS) scores were evaluated in 26 schizophrenic patients who had either never been medicated (neuroleptic-naive, first-episode subjects) or whose condition had become exacerbated following neuroleptic discontinuance (exacerbated subjects). All the subjects received medication with a fixed dose of a neuroleptic (haloperidol or fluphenazine, both 9 mg/day) for the first week and variable doses for the subsequent 4 weeks. In the neuroleptic-naive subjects, pHVA levels increased significantly 1 week after starting the protocol; this increase correlated significantly with clinical improvement of the BPRS positive symptom scores at week 5. In the neuroleptic-naive subjects, pHVA levels had declined to the baseline level by week 5. In the exacerbated subjects, there were no significant correlations between pHVA level changes at week 1 and later improvements of the BPRS positive symptom scores. These results suggest that the rise in pHVA levels occurring within 1 week after starting a fixed neuroleptic dose may predict a favorable clinical response in neuroleptic-naive schizophrenic patients.

  12. A randomised trial into the effect of an isolated hip abductor strengthening programme and a functional motor control programme on knee kinematics and hip muscle strength.

    PubMed

    Palmer, Kathryn; Hebron, Clair; Williams, Jonathan M

    2015-05-03

    Dynamic knee valgus and internal femoral rotation are proposed to be contributory risk factors for patellofemoral pain and anterior cruciate ligament injuries. Multimodal interventions including hip abductor strengthening or functional motor control programmes have a positive impact of pain, however their effect on knee kinematics and muscle strength is less clear. The aim of this study was to examine the effect of isolated hip abductor strengthening and a functional motor control exercise on knee kinematics and hip abductor strength. This prospective, randomised, repeated measures design included 29 asymptomatic volunteers presenting with increase knee valgus and femoral internal rotation. Participants completed either isolated hip abductor strengthening or a functional motor control exercise for 5 weeks. Knee kinematics were measured using inertial sensors during 2 functional activities and hip abductor strength measured using a load cell during isometric hip abduction. There were no significant differences in dynamic knee valgus and internal rotation following the isolated hip abductor or functional motor control intervention, and no significant differences between the groups for knee angles. Despite this, the actual magnitude of reduction in valgus was 10° and 5° for the functional motor control group and strengthening group respectively. The actual magnitude of reduction in internal rotation was 9° and 18° for the functional motor control group and strengthening group respectively. Therefore there was a tendency towards clinically significant improvements in knee kinematics in both exercise groups. A statistically significant improvement in hip abductor strength was evident for the functional motor control group (27% increase; p = 0.008) and strengthening group (35% increase; p = 0.009) with no significant difference between the groups being identified (p = 0.475). Isolated hip strengthening and functional motor control exercises resulted in

  13. Angle closure in younger patients.

    PubMed Central

    Chang, Brian M; Liebmann, Jeffrey M; Ritch, Robert

    2002-01-01

    PURPOSE: Angle-closure glaucoma is rare in children and young adults. Only scattered cases associated with specific clinical entities have been reported. We evaluated the findings in patients in our database aged 40 or younger with angle closure. METHODS: Our database was searched for patients with angle closure who were 40 years old or younger. Data recorded included age at initial consultation; age at the time of diagnosis; gender; results of slit-lamp examination, gonioscopy, and ultrasound biomicroscopy (from 1993 onward); clinical diagnosis; and therapy. Patients with previous incisional surgery were excluded, as were patients with anterior chamber proliferative mechanisms leading to angle closure. RESULTS: Sixty-seven patients (49 females, 18 males) met entry criteria. Mean age (+/- SD) at the time of consultation was 34.4 +/- 9.4 years (range, 3-68 years). Diagnoses included plateau iris syndrome (35 patients), iridociliary cysts (8 patients), retinopathy of prematurity (7 patients), uveitis (5 patients), isolated nanophthalmos (3 patients), relative pupillary block (2 patients), Weill-Marchesani syndrome (3 patients), and 1 patient each with Marfan syndrome, miotic-induced angle closure, persistent hyperplastic primary vitreous, and idiopathic lens subluxation. CONCLUSION: The etiology of angle closure in young persons is different from that in the older population and is typically associated with structural or developmental ocular anomalies rather than relative pupillary block. Following laser iridotomy, these eyes should be monitored for recurrent angle closure and the need for additional laser or incisional surgical intervention. PMID:12545694

  14. Rotation of intramedullary alignment rods affects distal femoral cutting plane in total knee arthroplasty.

    PubMed

    Maderbacher, Günther; Matussek, Jan; Keshmiri, Armin; Greimel, Felix; Baier, Clemens; Grifka, Joachim; Maderbacher, Hermann

    2018-02-17

    Intramedullary rods are widely used to align the distal femoral cut in total knee arthroplasty. We hypothesised that both coronal (varus/valgus) and sagittal (extension/flexion) cutting plane are affected by rotational changes of intramedullary femoral alignment guides. Distal femoral cuts using intramedullary alignment rods were simulated by means of a computer-aided engineering software in 4°, 6°, 8°, 10°, and 12° of valgus in relation to the femoral anatomical axis and 4° extension, neutral, as well as 4°, 8°, and 12° of flexion in relation to the femoral mechanical axis. This reflects the different angles between anatomical and mechanical axis in coronal and sagittal planes. To assess the influence of rotation of the alignment guide on the effective distal femoral cutting plane, all combinations were simulated with the rod gradually aligned from 40° of external to 40° of internal rotation. Rotational changes of the distal femoral alignment guides affect both the coronal and sagittal cutting planes. When alignment rods are intruded neutrally with regards to sagittal alignment, external rotation causes flexion, while internal rotation causes extension of the sagittal cutting plane. Simultaneously the coronal effect (valgus) decreases resulting in an increased varus of the cutting plane. However, when alignment rods are intruded in extension or flexion partly contradictory effects are observed. Generally the effect increases with the degree of valgus preset, rotation and flexion. As incorrect rotation of intramedullary alignment guides for distal femoral cuts causes significant cutting errors, exact rotational alignment is crucial. Coronal cutting errors in the distal femoral plane might result in overall leg malalignment, asymmetric extension gaps and subsequent sagittal cutting errors.

  15. SU-E-T-446: Group-Sparsity Based Angle Generation Method for Beam Angle Optimization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gao, H

    2015-06-15

    Purpose: This work is to develop the effective algorithm for beam angle optimization (BAO), with the emphasis on enabling further improvement from existing treatment-dependent templates based on clinical knowledge and experience. Methods: The proposed BAO algorithm utilizes a priori beam angle templates as the initial guess, and iteratively generates angular updates for this initial set, namely angle generation method, with improved dose conformality that is quantitatively measured by the objective function. That is, during each iteration, we select “the test angle” in the initial set, and use group-sparsity based fluence map optimization to identify “the candidate angle” for updating “themore » test angle”, for which all the angles in the initial set except “the test angle”, namely “the fixed set”, are set free, i.e., with no group-sparsity penalty, and the rest of angles including “the test angle” during this iteration are in “the working set”. And then “the candidate angle” is selected with the smallest objective function value from the angles in “the working set” with locally maximal group sparsity, and replaces “the test angle” if “the fixed set” with “the candidate angle” has a smaller objective function value by solving the standard fluence map optimization (with no group-sparsity regularization). Similarly other angles in the initial set are in turn selected as “the test angle” for angular updates and this chain of updates is iterated until no further new angular update is identified for a full loop. Results: The tests using the MGH public prostate dataset demonstrated the effectiveness of the proposed BAO algorithm. For example, the optimized angular set from the proposed BAO algorithm was better the MGH template. Conclusion: A new BAO algorithm is proposed based on the angle generation method via group sparsity, with improved dose conformality from the given template. Hao Gao was partially supported by

  16. Individualized optimal release angles in discus throwing.

    PubMed

    Leigh, Steve; Liu, Hui; Hubbard, Mont; Yu, Bing

    2010-02-10

    The purpose of this study was to determine individualized optimal release angles for elite discus throwers. Three-dimensional coordinate data were obtained for at least 10 competitive trials for each subject. Regression relationships between release speed and release angle, and between aerodynamic distance and release angle were determined for each subject. These relationships were linear with subject-specific characteristics. The subject-specific relationships between release speed and release angle may be due to subjects' technical and physical characteristics. The subject-specific relationships between aerodynamic distance and release angle may be due to interactions between the release angle, the angle of attack, and the aerodynamic distance. Optimal release angles were estimated for each subject using the regression relationships and equations of projectile motion. The estimated optimal release angle was different for different subjects, and ranged from 35 degrees to 44 degrees . The results of this study demonstrate that the optimal release angle for discus throwing is thrower-specific. The release angles used by elite discus throwers in competition are not necessarily optimal for all discus throwers, or even themselves. The results of this study provide significant information for understanding the biomechanics of discus throwing techniques. Copyright 2009 Elsevier Ltd. All rights reserved.

  17. The Semiotic and Conceptual Genesis of Angle

    ERIC Educational Resources Information Center

    Tanguay, Denis; Venant, Fabienne

    2016-01-01

    In the present study, we try to understand how students at the end of primary school conceive of angle: Is an angle a magnitude for them or a geometric figure, and how do they manage to coordinate the two aspects in their understanding of the concepts of angle and of angle measurement? With the aim of better grasping the way "angle" is…

  18. SU-E-I-56: Scan Angle Reduction for a Limited-Angle Intrafraction Verification (LIVE) System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ren, L; Zhang, Y; Yin, F

    Purpose: To develop a novel adaptive reconstruction strategy to further reduce the scanning angle required by the limited-angle intrafraction verification (LIVE) system for intrafraction verification. Methods: LIVE acquires limited angle MV projections from the exit fluence of the arc treatment beam or during gantry rotation between static beams. Orthogonal limited-angle kV projections are also acquired simultaneously to provide additional information. LIVE considers the on-board 4D-CBCT images as a deformation of the prior 4D-CT images, and solves the deformation field based on deformation models and data fidelity constraint. LIVE reaches a checkpoint after a limited-angle scan, and reconstructs 4D-CBCT for intrafractionmore » verification at the checkpoint. In adaptive reconstruction strategy, a larger scanning angle of 30° is used for the first checkpoint, and smaller scanning angles of 15° are used for subsequent checkpoints. The onboard images reconstructed at the previous adjacent checkpoint are used as the prior images for reconstruction at the current checkpoint. As the algorithm only needs to reconstruct the small deformation occurred between adjacent checkpoints, projections from a smaller scan angle provide enough information for the reconstruction. XCAT was used to simulate tumor motion baseline drift of 2mm along sup-inf direction at every subsequent checkpoint, which are 15° apart. Adaptive reconstruction strategy was used to reconstruct the images at each checkpoint using orthogonal 15° kV and MV projections. Results: Results showed that LIVE reconstructed the tumor volumes accurately using orthogonal 15° kV-MV projections. Volume percentage differences (VPDs) were within 5% and center of mass shifts (COMS) were within 1mm for reconstruction at all checkpoints. Conclusion: It's feasible to use an adaptive reconstruction strategy to further reduce the scan angle needed by LIVE to allow faster and more frequent intrafraction verification to

  19. [Modified chevron osteotomy with lateral release and screw fixation for treatment of severe hallux deformity].

    PubMed

    Hofstaetter, S G; Schuh, R; Trieb, K; Trnka, H J

    2012-12-01

    This prospective study examined the clinical and radiological results of the Chevron osteotomy with screw fixation and distal soft tissue release up to an intermetatarsal angle of 19°. Furthermore, the results are presented for patients over the age of 70 years, and whether or not there is a higher complication rate. 86 feet of patients between 23 and 81 years were included in the study. Apart from the overall group, a group with an intermetatarsal angle of 16° to 19° and a group of patients over 70 years old were eavaluated. They were evaluated preoperatively and at follow-up after an average of 3.3 years according to the American Orthopaedic Foot and Ankle Society score. The AOFAS score showed a significant improvement from 55 points preoperatively to 90 points at follow-up. The preoperative hallux valgus angle decreased significantly from 32° to 5° and the preoperative intermetatarsal angle decreased from 14° to 6°. Patient satisfaction in the overall group was rated in 92 % as excellent or good. Also, the patient group with 16° to 19° angles and the patients over 70 years showed a significant improvement of clinical and radiological parameters. The complication rate was very low in all groups. The results show that the Chevron osteotomy is a very good surgical technique with few complications for the correction of splay foot with hallux valgus deformity. We showed that by using the modified technique with a long plantar arm, an excessive soft tissue release and screw fixation, the indication can be extended up to an intermetatarsal angle of 19° when using screw fixation. Furthermore the patients over 70 years of age showed a significant improvement of clinical and radiological parameters without serious complications such as avascular necrosis or dislocation of the metatarsal head. Georg Thieme Verlag KG Stuttgart · New York.

  20. Spinning angle optical calibration apparatus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beer, S.K.; Pratt, H.R.

    1991-02-26

    This patent describes an optical calibration apparatus provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting an accurate reproducing of spinning magic angles in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the magic angle of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to amore » graduation or graduations on a reticle in the magnifying scope is noted.« less

  1. Northwest Angle, Minnesota

    NASA Image and Video Library

    2017-10-02

    Minnesota's Northwest Angle is the northernmost point of the continental United States. The Angle became part of the US due to a map error during the 1783 Treaty of Paris. Located in the Lake of the Woods, driving there requires crossing the US-Canada border twice. The image was acquired September 22, 2013, covers an area of 40 by 55 km, and is located at 49.2 degrees north, 95.1 degrees west. https://photojournal.jpl.nasa.gov/catalog/PIA21997

  2. Effects of debrisoquin and haloperidol on plasma homovanillic acid concentration in schizophrenic patients.

    PubMed

    Davidson, M; Losonczy, M F; Mohs, R C; Lesser, J C; Powchik, P; Freed, L B; Davis, B M; Mykytyn, V V; Davis, K L

    1987-12-01

    Plasma levels of the dopamine metabolite homovanillic acid (pHVA) may potentially reflect upon central dopamine activity. This study examines the effects of debrisoquin, haloperidol, and the two drugs combined on pHVA concentrations of schizophrenic patients. Debrisoquin is a drug that suppresses the peripheral formation of homovanillic acid without affecting the central formation. Acute haloperidol administration consistently increased pHVA concentrations in patients pretreated or not pretreated with debrisoquin, suggesting that this increment reflects haloperidol's central and not peripheral effects.

  3. Ultrasound evaluation of intrinsic plantar muscles and fascia in hallux valgus: A case-control study.

    PubMed

    Lobo, César Calvo; Marín, Alejandro Garrido; Sanz, David Rodríguez; López, Daniel López; López, Patricia Palomo; Morales, Carlos Romero; Corbalán, Irene Sanz

    2016-11-01

    A cross-sectional area (CSA) and thickness reduction of the abductor hallucis (AbH) is shown in subjects with hallux valgus (HV). To date, other soft-tissue structures have not been researched in relation with HV. The aim of this study was to compare the CSA and thickness of the intrinsic plantar muscles and fascia (PF) between feet with and without HV. Therefore, a cross-sectional and case-control study was performed using B-mode with an iU22 Philips ultrasound system and a 5 to 17-MHz transducer. The CSA and thickness were measured for the AbH, flexor digitorum brevis (FDB) and flexor hallucis brevis (FHB), and also the thickness for the anterior, middle, and posterior PF portions. A convenience sample of 40 feet, 20 with HV and 20 without HV, was recruited from a clinical and research center. A multivariate regression analysis using linear regression was performed to evaluate the ultrasound imaging measurements (α = 0.05). Consequently, statistically significant differences were observed between the groups (P < 0.05) for the AbH and FHB thickness, and CSA reduction, and also the plantar fascia thickness increase in favor of the HV group. On the contrary, the FDB thickness and CSA did not show statistically significant differences (P ≥ 0.05). In conclusion, the CSA and thickness of the AbH and FHB intrinsic plantar muscles are reduced, whereas the thickness of the anterior, middle, and posterior PF portions are increased, in subjects with HV compared with those without HV.

  4. Reading Angles in Maps

    ERIC Educational Resources Information Center

    Izard, Véronique; O'Donnell, Evan; Spelke, Elizabeth S.

    2014-01-01

    Preschool children can navigate by simple geometric maps of the environment, but the nature of the geometric relations they use in map reading remains unclear. Here, children were tested specifically on their sensitivity to angle. Forty-eight children (age 47:15-53:30 months) were presented with fragments of geometric maps, in which angle sections…

  5. Bunion correction using proximal chevron osteotomy: a single-incision technique.

    PubMed

    Sammarco, G J; Russo-Alesi, F G

    1998-07-01

    Proximal chevron first metatarsal osteotomy with lateral capsulotomy, adductor tenotomy, and binding of the first and second metatarsals was reviewed in 88 consecutive cases. Seventy-two cases in 55 patients are reported, with an average clinical follow-up of 41 months. The hallux valgus angle improved an average of 15 degrees , from 32.0 degrees preoperatively to an average of 17.0 degrees postoperatively. The intermetatarsal I-II angle improved an average of 5.5 degrees, from 15.3 degrees preoperatively to 9.0 degrees postoperatively. The lateral plantar first metatarsal angle did not change. First metatarsal length was decreased by 2.0 mm. Union occurred at an average of 2 months. Sesamoid position improved 49%, from a preoperative average subluxation of 80% to a postoperative average subluxation of 29%. Subjective foot score profiles improved from a preoperative average of 70.1/100 to a postoperative average of 94.4/100 with respect to pain, deformity, motion, disability, and cosmesis. There were 10 patients with complications, including three patients with delayed unions, two with second metatarsal stress fractures, one with hallux varus, two with hallux limitus, one with progressive arthritis, one with cellulitis, and one with hallux elevatus. Eighty-four percent of the patients stated that they would undergo the procedure again without reservation, 9% would proceed with reservation, and 7% would not proceed with surgery again if offered. This technique provides reliable successful long-term results for the treatment of moderate and severe symptomatic bunion, hallux valgus, and metatarsus primus varus.

  6. Pitch Angles Of Artificially Redshifted Galaxies

    NASA Astrophysics Data System (ADS)

    Shields, Douglas W.; Davis, B.; Johns, L.; Berrier, J. C.; Kennefick, D.; Kennefick, J.; Seigar, M.

    2012-05-01

    We present the pitch angles of several galaxies that have been artificially redshifted using Barden et al’s FERENGI software. The (central black hole mass)-(spiral arm pitch angle) relation has been used on a statistically complete sample of local galaxies to determine the black hole mass function of local spiral galaxies. We now measure the pitch angles at increasing redshifts by operating on the images pixel-by-pixel. The results will be compared to the pitch angle function as measured in the GOODS field. This research was funded in part by NASA / EPScOR.

  7. Relationship of symptomatology, gender, and antipsychotic drug treatment with plasma homovanillic acid in schizophrenia.

    PubMed

    Zhang, Z J; Reynolds, G P; Ramchand, C; Peet, M; Shah, S

    2001-01-01

    To study the role of dopamine neurotransmission in schizophrenia and its drug treatment by assessing the relationship of plasma homovanillic acid (pHVA), a major central dopamine metabolite to various clinical parameters in schizophrenic patients. pHVA was measured by high-performance liquid chromatography with electrochemical detection in a large cohort of both medicated and unmedicated DSM-IV schizophrenic patients. Prior to the measurement of pHVA, the patients were rated on the schedule for the assessment of positive and negative symptoms (PANSS). (1) pHVA in 46 patients receiving antipsychotic drugs was decreased, and in 58 drug-free patients increased, (7.4+/-2.7) microg/L and (10+/-4) microg/L compared with a matched control group (9 microg/L+/-3 microg/L, n=62) (ANOVA F=8.57, df=2, P < 0.01), respectively. Within the drug-free group, pHVA was higher in the patients with a more negative symptom profile. (2) No significant correlation of pHVA with overall SAPS or SANS scores was apparent in the drug-free patients, although within the SANS subscales, a significant relationships to anhedonia-asociality (r=0.32, P < 0.05) was apparent. The male drug-free patients showed a positive correlation of pHVA with negative symptoms (r=0.42, P < 0.05) while females showed no significant relationship with any PANSS subscales. The results suggest that an increased dopaminergic metabolism is apparent in (male) schizophrenic patients with predominantly negative symptoms, supporting reports that this change in neuronal activity may be related to the neuropathological abnormalities seen in the disease, which may differ between males and females. Such neuronal deficits of developmental origin may thus result in an elevation/disinhibition of central dopamine metabolism in schizophrenia.

  8. Omni-Directional Viewing-Angle Switching through Control of the Beam Divergence Angle in a Liquid Crystal Panel

    NASA Astrophysics Data System (ADS)

    Baek, Jong-In; Kim, Ki-Han; Kim, Jae Chang; Yoon, Tae-Hoon

    2010-01-01

    This paper proposes a method of omni-directional viewing-angle switching by controlling the beam diverging angle (BDA) in a liquid crystal (LC) panel. The LCs aligned randomly by in-cell polymer structures diffuse the collimated backlight for the bright state of the wide viewing-angle mode. We align the LCs homogeneously by applying an in-plane field for the narrow viewing-angle mode. By doing this the scattering is significantly reduced so that the small BDA is maintained as it passes through the LC layer. The dark state can be obtained by aligning the LCs homeotropically with a vertical electric field. We demonstrated experimentally the omni-directional switching of the viewing-angle, without an additional panel or backlighting system.

  9. Does the Angle of the Nail Matter for Pertrochanteric Fracture Reduction? Matching Nail Angle and Native Neck-Shaft Angle.

    PubMed

    Parry, Joshua A; Barrett, Ian; Schoch, Bradley; Yuan, Brandon; Cass, Joseph; Cross, William

    2018-04-01

    To determine whether fixation of pertrochanteric hip fractures with cephalomedullary nails (CMNs) with a neck-shaft angle (NSA) less than the native NSA affects reduction and lag screw cutout. Retrospective comparative study. Level I trauma center. Patients treated with a CMN for unstable pertrochanteric femur fractures (OTA/AO 31-A2.2 and 31-A2.3) between 2005 and 2014. CMN fixation. NSA reduction and lag screw cutout. Patients fixed with a nail angle less than their native NSA were less likely to have good reductions [17% vs. 60%, 95% confidence interval (CI), -63% to -18%; P = 0.0005], secondary to more varus reductions (41% vs. 10%, 95% CI, 9%-46%; P = 0.01) and more fractures with ≥4 mm of displacement (63% vs. 35%, 95% CI, 3%-49%; P = 0.03). The cutout was not associated with the use of a nail angle less than the native NSA (60% vs. 76%, 95% CI, -56% to 18%; P = 0.5), varus reductions (60% vs. 32%, 95% CI, -13% to 62%; P = 0.3), or poor reductions (20% vs. 17%, 95% CI, -24% to 44%; P = 1.0). The fixation of unstable pertrochanteric hip fractures with a nail angle less than the native NSA was associated with more varus reductions and fracture displacement but did not affect the lag screw cutout. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

  10. Correlation between plasma homovanillic acid levels and the response to atypical antipsychotics in male patients with schizophrenia.

    PubMed

    Kaneda, Yasuhiro; Kawamura, Ichiro; Ohmori, Tetsuro

    2005-01-01

    The authors investigated the effects of atypical antipsychotic drugs-olanzapine, perospirone, and quetiapine-on plasma homovanillic acid (pHVA) in male patients with chronic schizophrenia. In this prospective, open-label study, the subjects were 30 inpatients who were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, criteria for schizophrenia. The authors switched patients from typical antipsychotic drugs to olanzapine, perospirone, or quetiapine. Each patient gave informed consent for the research. pHVA was assessed before and after switching medications. After the switch, the authors found a significant improvement in psychotic symptoms, nonsignificant improvement in extrapyramidal symptoms, and a nonsignificant reduction in pHVA. In addition, the baseline pHVA correlated positively with the score changes from baseline in the Brief Psychiatric Rating Scale (BPRS) total, positive, and negative symptoms in the group with a whole sample and in the olanzapine-treated group, and with the score changes in the BPRS total and positive symptoms in the quetiapine-treated group. Our findings indicated that the preswitching pHVA levels could be used to predict changes in the psychotic symptoms of male patients with chronic schizophrenia when switching to atypical antipsychotic drugs.

  11. Plasma homovanillic acid correlates inversely with history of learning problems in healthy volunteer and personality disordered subjects.

    PubMed

    Coccaro, Emil F; Hirsch, Sharon L; Stein, Mark A

    2007-01-15

    Central dopaminergic activity is critical to the functioning of both motor and cognitive systems. Based on the therapeutic action of dopaminergic agents in treating attention deficit hyperactivity disorder (ADHD), ADHD symptoms may be related to a reduction in central dopaminergic activity. We tested the hypothesis that dopaminergic activity, as reflected by plasma homovanillic acid (pHVA), may be related to dimensional aspects of ADHD in adults. Subjects were 30 healthy volunteer and 39 personality disordered subjects, in whom morning basal pHVA concentration and a dimensional measure of childhood ADHD symptoms (Wender Utah Rating Scale: WURS) were obtained. A significant inverse correlation was found between WURS Total score and pHVA concentration in the total sample. Among WURS factor scores, a significant inverse relationship was noted between pHVA and history of "childhood learning problems". Consistent with the dopaminergic dysfunction hypothesis of ADHD and of cognitive function, pHVA concentrations were correlated with childhood history of ADHD symptoms in general and with history of "learning problems" in non-ADHD psychiatric patients and controls. Replication is needed in treated and untreated ADHD samples to confirm these initial results.

  12. Haloperidol response and plasma catecholamines and their metabolites.

    PubMed

    Green, A I; Alam, M Y; Boshes, R A; Waternaux, C; Pappalardo, K M; Fitzgibbon, M E; Tsuang, M T; Schildkraut, J J

    1993-06-01

    Eleven acutely psychotic patients with schizophrenia or schizoaffective disorder underwent a 5-7 day drug-washout period (with lorazepam allowed) prior to participating in a 6-week controlled dose haloperidol trial. Patients were evaluated longitudinally with clinical ratings and with plasma measures of the catecholamines dopamine (pDA) and norepinephrine (pNE) and their metabolites, homovanillic acid (pHVA) and 3-methoxy-4-hydroxyphenylglycol (pMHPG). All patients exhibited clinical improvement with haloperidol; the decrease in their Brief Psychiatric Rating Scale (BPRS) scores ranged from 32 to 89%. Measures of pHVA increased within the first week of treatment and returned to baseline by week 5. The pattern of change of pDA resembled that of pHVA. The pattern of change of pNE and pMHPG revealed a decrease over the course of treatment. The early increase and the subsequent decrease in pHVA were strongly correlated with improvement in positive symptoms on the BPRS. These data are consistent with previous reports on the change in pHVA and pMHPG during clinical response to haloperidol. The data on change of pDA and pNE further describe the nature of the biochemical response to this drug.

  13. Angle amplifier based on multiplexed volume holographic gratings

    NASA Astrophysics Data System (ADS)

    Cao, Liangcai; Zhao, Yifei; He, Qingsheng; Jin, Guofan

    2008-03-01

    Angle amplifier of laser beam scanner is a widely used device in optical systems. Volume holographic optical elements can be applied in the angle amplifier. Compared with the traditional angle amplifier, it has the advantages of high angle resolution, high diffraction efficiency, small size, and high angle magnification and flexible design. Bragg anglewavelength- compensating recording method is introduced. Because of the Bragg compensatory relation between angle and wavelength, this device could be recorded at another wavelength. The design of the angle amplifier recording at the wavelength of 514.2nm for the working wavelength of 632.8nm is described. An optical setup for recording the angle amplifier device is designed and discussed. Experimental results in the photorefractive crystal Fe:LiNbO 3 demonstrate the feasibility of the angle amplifier scheme.

  14. Anterior Segment Imaging Predicts Incident Gonioscopic Angle Closure.

    PubMed

    Baskaran, Mani; Iyer, Jayant V; Narayanaswamy, Arun K; He, Yingke; Sakata, Lisandro M; Wu, Renyi; Liu, Dianna; Nongpiur, Monisha E; Friedman, David S; Aung, Tin

    2015-12-01

    To investigate the incidence of gonioscopic angle closure after 4 years in subjects with gonioscopically open angles but varying degrees of angle closure detected on anterior segment optical coherence tomography (AS OCT; Visante; Carl Zeiss Meditec, Dublin, CA) at baseline. Prospective, observational study. Three hundred forty-two subjects, mostly Chinese, 50 years of age or older, were recruited, of whom 65 were controls with open angles on gonioscopy and AS OCT at baseline, and 277 were cases with baseline open angles on gonioscopy but closed angles (1-4 quadrants) on AS OCT scans. All subjects underwent gonioscopy and AS OCT at baseline (horizontal and vertical single scans) and after 4 years. The examiner performing gonioscopy was masked to the baseline and AS OCT data. Angle closure in a quadrant was defined as nonvisibility of the posterior trabecular meshwork by gonioscopy and visible iridotrabecular contact beyond the scleral spur in AS OCT scans. Gonioscopic angle closure in 2 or 3 quadrants after 4 years. There were no statistically significant differences in age, ethnicity, or gender between cases and controls. None of the control subjects demonstrated gonioscopic angle closure after 4 years. Forty-eight of the 277 subjects (17.3%; 95% confidence interval [CI], 12.8-23; P < 0.0001) with at least 1 quadrant of angle closure on AS OCT at baseline demonstrated gonioscopic angle closure in 2 or more quadrants, whereas 28 subjects (10.1%; 95% CI, 6.7-14.6; P < 0.004) demonstrated gonioscopic angle closure in 3 or more quadrants after 4 years. Individuals with more quadrants of angle closure on baseline AS OCT scans had a greater likelihood of gonioscopic angle closure developing after 4 years (P < 0.0001, chi-square test for trend for both definitions of angle closure). Anterior segment OCT imaging at baseline predicts incident gonioscopic angle closure after 4 years among subjects who have gonioscopically open angles and iridotrabecular contact on AS OCT at

  15. Influence of Contact Angle, Growth Angle and Melt Surface Tension on Detached Solidification of InSb

    NASA Technical Reports Server (NTRS)

    Wang, Yazhen; Regel, Liya L.; Wilcox, William R.

    2000-01-01

    We extended the previous analysis of detached solidification of InSb based on the moving meniscus model. We found that for steady detached solidification to occur in a sealed ampoule in zero gravity, it is necessary for the growth angle to exceed a critical value, the contact angle for the melt on the ampoule wall to exceed a critical value, and the melt-gas surface tension to be below a critical value. These critical values would depend on the material properties and the growth parameters. For the conditions examined here, the sum of the growth angle and the contact angle must exceed approximately 130, which is significantly less than required if both ends of the ampoule are open.

  16. Modified Angle's Classification for Primary Dentition.

    PubMed

    Chandranee, Kaushik Narendra; Chandranee, Narendra Jayantilal; Nagpal, Devendra; Lamba, Gagandeep; Choudhari, Purva; Hotwani, Kavita

    2017-01-01

    This study aims to propose a modification of Angle's classification for primary dentition and to assess its applicability in children from Central India, Nagpur. Modification in Angle's classification has been proposed for application in primary dentition. Small roman numbers i/ii/iii are used for primary dentition notation to represent Angle's Class I/II/III molar relationships as in permanent dentition, respectively. To assess applicability of modified Angle's classification a cross-sectional preschool 2000 children population from central India; 3-6 years of age residing in Nagpur metropolitan city of Maharashtra state were selected randomly as per the inclusion and exclusion criteria. Majority 93.35% children were found to have bilateral Class i followed by 2.5% bilateral Class ii and 0.2% bilateral half cusp Class iii molar relationships as per the modified Angle's classification for primary dentition. About 3.75% children had various combinations of Class ii relationships and 0.2% children were having Class iii subdivision relationship. Modification of Angle's classification for application in primary dentition has been proposed. A cross-sectional investigation using new classification revealed various 6.25% Class ii and 0.4% Class iii molar relationships cases in preschool children population in a metropolitan city of Nagpur. Application of the modified Angle's classification to other population groups is warranted to validate its routine application in clinical pediatric dentistry.

  17. Modified Angle's Classification for Primary Dentition

    PubMed Central

    Chandranee, Kaushik Narendra; Chandranee, Narendra Jayantilal; Nagpal, Devendra; Lamba, Gagandeep; Choudhari, Purva; Hotwani, Kavita

    2017-01-01

    Aim: This study aims to propose a modification of Angle's classification for primary dentition and to assess its applicability in children from Central India, Nagpur. Methods: Modification in Angle's classification has been proposed for application in primary dentition. Small roman numbers i/ii/iii are used for primary dentition notation to represent Angle's Class I/II/III molar relationships as in permanent dentition, respectively. To assess applicability of modified Angle's classification a cross-sectional preschool 2000 children population from central India; 3–6 years of age residing in Nagpur metropolitan city of Maharashtra state were selected randomly as per the inclusion and exclusion criteria. Results: Majority 93.35% children were found to have bilateral Class i followed by 2.5% bilateral Class ii and 0.2% bilateral half cusp Class iii molar relationships as per the modified Angle's classification for primary dentition. About 3.75% children had various combinations of Class ii relationships and 0.2% children were having Class iii subdivision relationship. Conclusions: Modification of Angle's classification for application in primary dentition has been proposed. A cross-sectional investigation using new classification revealed various 6.25% Class ii and 0.4% Class iii molar relationships cases in preschool children population in a metropolitan city of Nagpur. Application of the modified Angle's classification to other population groups is warranted to validate its routine application in clinical pediatric dentistry. PMID:29326514

  18. Angle detector

    NASA Technical Reports Server (NTRS)

    Parra, G. T. (Inventor)

    1978-01-01

    An angle detector for determining a transducer's angular disposition to a capacitive pickup element is described. The transducer comprises a pendulum mounted inductive element moving past the capacitive pickup element. The capacitive pickup element divides the inductive element into two parts L sub 1 and L sub 2 which form the arms of one side of an a-c bridge. Two networks R sub 1 and R sub 2 having a plurality of binary weighted resistors and an equal number of digitally controlled switches for removing resistors from the networks form the arms of the other side of the a-c bridge. A binary counter, controlled by a phase detector, balances the bridge by adjusting the resistance of R sub 1 and R sub 2. The binary output of the counter is representative of the angle.

  19. Frontal plane comparison between drop jump and vertical jump: implications for the assessment of ACL risk of injury.

    PubMed

    Cesar, Guilherme M; Tomasevicz, Curtis L; Burnfield, Judith M

    2016-11-01

    The potential to use the vertical jump (VJ) to assess both athletic performance and risk of anterior cruciate ligament (ACL) injury could have widespread clinical implications since VJ is broadly used in high school, university, and professional sport settings. Although drop jump (DJ) and VJ observationally exhibit similar lower extremity mechanics, the extent to which VJ can also be used as screening tool for ACL injury risk has not been assessed. This study evaluated whether individuals exhibit similar knee joint frontal plane kinematic and kinetic patterns when performing VJs compared with DJs. Twenty-eight female collegiate athletes performed DJs and VJs. Paired t-tests indicated that peak knee valgus angles did not differ significantly between tasks (p = 0.419); however, peak knee internal adductor moments were significantly larger during the DJ vs. VJ (p < 0.001). Pearson correlations between the DJ and VJ revealed strong correlations for knee valgus angles (r = 0.93, p < 0.001) and for internal knee adductor moments (r = 0.82, p < 0.001). Our results provide grounds for investigating whether frontal plane knee mechanics during VJ can predict ACL injuries and thus can be used as an effective tool for the assessment of risk of ACL injury in female athletes.

  20. Long-term results of fibular-Achilles tenodesis (Westin's tenodesis) for paralytic pes calcaneus: is hypercorrection avoidable? A longitudinal retrospective study.

    PubMed

    Yamada, Helder Henzo; Fucs, Patricia Maria Moraes de Barros

    2017-08-01

    The purpose of this study was to review all cases of patients submitted to Westin's tenodesis, who had calcaneus feet secondary to myelomeningocele sequel, in order to evaluate the anatomical change provided by surgery and also to verify, in a long-term follow-up, the inversion of the deformity depending on the patient's age. In this longitudinal retrospective study, all medical records of patients with myelomeningocele sequelae submitted to Westin's tenodesis from 1993 to 2013 in a public university hospital were reviewed. Patients were contacted for new clinical and radiographic evaluations after a minimum of 36 months after surgery. The calcaneotibial angle was measured and the shortening of the fibula was calculated as the "intermalleolar height". The study was based on 16 children (26 feet), aged 84.27 months on average at the time of tenodesis. The calcaneotibial angle increased significantly post-operatively, from 63.77 degrees on average to 70.54 degrees. Intermalleolar height and valgus ankle did not change significantly. Most patients had plantigrade feet after surgery, without pressure ulcers, and were able to use orthoses. Westin's tenodesis, with or without other associated procedures, can correct or improve the calcaneus and valgus ankle deformity in patients with myelomeningocele sequelae. There was no association of the surgical result with age at the time of surgery. There was no inversion of the deformity in equinus during the follow-up time.

  1. Hong's grading for evaluating anterior chamber angle width.

    PubMed

    Kim, Seok Hwan; Kang, Ja Heon; Park, Ki Ho; Hong, Chul

    2012-11-01

    To compare Hong's grading method with anterior segment optical coherence tomography (AS-OCT), gonioscopy, and the dark-room prone-position test (DRPT) for evaluating anterior chamber width. The anterior chamber angle was graded using Hong's grading method, and Hong's angle width was calculated from the arctangent of Hong's grades. The correlation between Hong's angle width and AS-OCT parameters was analyzed. The area under the receiver operating characteristic curve (AUC) for Hong's grading method when discriminating between narrow and open angles as determined by gonioscopy was calculated. Correlation analysis was performed between Hong's angle width and intraocular pressure (IOP) changes determined by DRPT. A total of 60 subjects were enrolled. Of these subjects, 53.5 % had a narrow angle. Hong's angle width correlated significantly with the AS-OCT parameters (r = 0.562-0.719, P < 0.01). A Bland-Altman plot showed relatively good agreement between Hong's angle width and the angle width obtained by AS-OCT. The ability of Hong's grading method to discriminate between open and narrow angles was good (AUC = 0.868, 95 % CI 0.756-0.942). A significant linear correlation was found between Hong's angle width and IOP change determined by DRPT (r = -0.761, P < 0.01). Hong's grading method is useful for detecting narrow angles. Hong's grading correlated well with AS-OCT parameters and DRPT.

  2. Assessment of knee laxity using a robotic testing device: a comparison to the manual clinical knee examination.

    PubMed

    Branch, T P; Stinton, S K; Siebold, R; Freedberg, H I; Jacobs, C A; Hutton, W C

    2017-08-01

    The purpose of this study was to collect knee laxity data using a robotic testing device. The data collected were then compared to the results obtained from manual clinical examination. Two human cadavers were studied. A medial collateral ligament (MCL) tear was simulated in the left knee of cadaver 1, and a posterolateral corner (PLC) injury was simulated in the right knee of cadaver 2. Contralateral knees were left intact. Five blinded examiners carried out manual clinical examination on the knees. Laxity grades and a diagnosis were recorded. Using a robotic knee device which can measure knee laxity in three planes of motion: anterior-posterior, internal-external tibia rotation, and varus-valgus, quantitative data were obtained to document tibial motion relative to the femur. One of the five examiners correctly diagnosed the MCL injury. Robotic testing showed a 1.7° larger valgus angle, 3° greater tibial internal rotation, and lower endpoint stiffness (11.1 vs. 24.6 Nm/°) in the MCL-injured knee during varus-valgus testing when compared to the intact knee and 4.9 mm greater medial tibial translation during rotational testing. Two of the five examiners correctly diagnosed the PLC injury, while the other examiners diagnosed an MCL tear. The PLC-injured knee demonstrated 4.1 mm more lateral tibial translation and 2.2 mm more posterior tibial translation during varus-valgus testing when compared to the intact knee. The robotic testing device was able to provide objective numerical data that reflected differences between the injured knees and the uninjured knees in both cadavers. The examiners that performed the manual clinical examination on the cadaver knees proved to be poor at diagnosing the injuries. Robotic testing could act as an adjunct to the manual clinical examination by supplying numbers that could improve diagnosis of knee injury. Level II.

  3. Contact angle hysteresis on superhydrophobic stripes.

    PubMed

    Dubov, Alexander L; Mourran, Ahmed; Möller, Martin; Vinogradova, Olga I

    2014-08-21

    We study experimentally and discuss quantitatively the contact angle hysteresis on striped superhydrophobic surfaces as a function of a solid fraction, ϕS. It is shown that the receding regime is determined by a longitudinal sliding motion of the deformed contact line. Despite an anisotropy of the texture the receding contact angle remains isotropic, i.e., is practically the same in the longitudinal and transverse directions. The cosine of the receding angle grows nonlinearly with ϕS. To interpret this we develop a theoretical model, which shows that the value of the receding angle depends both on weak defects at smooth solid areas and on the strong defects due to the elastic energy of the deformed contact line, which scales as ϕS(2)lnϕS. The advancing contact angle was found to be anisotropic, except in a dilute regime, and its value is shown to be determined by the rolling motion of the drop. The cosine of the longitudinal advancing angle depends linearly on ϕS, but a satisfactory fit to the data can only be provided if we generalize the Cassie equation to account for weak defects. The cosine of the transverse advancing angle is much smaller and is maximized at ϕS ≃ 0.5. An explanation of its value can be obtained if we invoke an additional energy due to strong defects in this direction, which is shown to be caused by the adhesion of the drop on solid sectors and is proportional to ϕS(2). Finally, the contact angle hysteresis is found to be quite large and generally anisotropic, but it becomes isotropic when ϕS ≤ 0.2.

  4. Do size, shape, and alignment parameters of the femoral condyle affect the trochlear groove tracking? A morphometric study based on 3D- computed tomography models in Chinese people.

    PubMed

    Du, Zhe; Chen, Shichang; Yan, Mengning; Yue, Bing; Zeng, Yiming; Wang, You

    2017-01-06

    Our study aimed to investigate whether geometrical features (size, shape, or alignment parameters) of the femoral condyle affect the morphology of the trochlear groove. Computed tomography models of 195 femurs (97 and 98 knees from male and female subjects, respectively) were reconstructed into three-dimensional models and categorised into four types of trochlear groove morphology based on the position of the turning point in relation to the mechanical axis (types 45°, 60°, 75°, and 90°). Only subjects with healthy knees were included, whereas individuals with previous knee trauma or knee pain, soft tissue injury, osteoarthritis, or other chronic diseases of the musculoskeletal system were excluded. The size parameters were: radius of the best-fit cylinder, anteroposterior dimension of the lateral condyles (AP), and distal mediolateral dimension (ML). The shape parameters were: aspect ratio (AP/ML), arc angle, and proximal- and distal- end angles. The alignment parameters were: knee valgus physiologic angle (KVPA), mechanical medial distal femoral angle (mMDFA), and hip-knee-ankle angle (HKA). All variables were measured in the femoral condyle models, and the means for each groove type were compared using one-way analysis of variance. No significant difference among groove types was observed regarding size parameters. There were significant differences when comparing type 45° with types 60°, 75°, and 90° regarding aspect ratio and distal-end angle (p < 0.05), but not regarding proximal-end angle. There were significant differences when comparing type 90° with types 45°, 60°, and 75° regarding KVPA, mMDFA, and HKA (p < 0.05). Among size, shape, and alignment parameters, the latter two exhibited partial influence on the morphology of the trochlear groove. Shape parameters affected the trochlear groove for trochlear type 45°, for which the femoral condyle was relatively flat, whereas alignment parameters affected the trochlear groove for trochlear

  5. An angle-by-angle approach to predicting broadband high-frequency sound fields in rectangular enclosures with experimental comparison.

    PubMed

    Franzoni, Linda P; Elliott, Christopher M

    2003-10-01

    Experiments were performed on an elongated rectangular acoustic enclosure with different levels of absorptive material placed on side walls and an end wall. The acoustic source was a broadband high-frequency sound from a loudspeaker flush-mounted to an end wall of the enclosure. Measurements of sound-pressure levels were averaged in cross sections of the enclosure and then compared to theoretical results. Discrepancies between the experimental results and theoretical predictions that treated all incidence angles as equally probable led to the development of an angle-by-angle approach. The new approach agrees well with the experimentally obtained values. In addition, treating the absorptive material as bulk reacting rather than point reacting was found to significantly change the theoretical value for the absorption coefficient and to improve agreement with experiment. The new theory refines an earlier theory based on power conservation and locally diffuse assumptions. Furthermore, the new theory includes both the angle of incidence effects on the resistive and reactive properties of the absorptive material, and the effects of angle filtering, i.e., that reflecting waves associated with shallow angles become relatively stronger than those associated with steep angles as a function of distance from the source.

  6. Effects of diurnal, lighting, and angle-of-incidence variation on anterior segment optical coherence tomography (AS-OCT) angle metrics.

    PubMed

    Akil, Handan; Dastiridou, Anna; Marion, Kenneth; Francis, Brian A; Chopra, Vikas

    2017-03-23

    First reported study to assess the effect of diurnal variation on anterior chamber angle measurements, as well as, to re-test the effects of lighting and angle-of-incidence variation on anterior chamber angle (ACA) measurements acquired by time-domain anterior segment optical coherence tomography (AS-OCT). A total of 30 eyes from 15 healthy, normal subjects underwent anterior chamber imaging using a Visante time-domain AS-OCT according to an IRB-approved protocol. For each eye, the inferior angle was imaged twice in the morning (8 am - 10 am) and then again in the afternoon (3 pm - 5 pm), under light meter-controlled conditions with ambient room lighting 'ON' and lights 'OFF', and at 5° angle of incidence increments. The ACA metrics measured for each eye were: angle opening distance (AOD, measured 500 and 750 μm anterior from scleral spur), the trabecular-iris-space area (TISA, measured 500 and 750 μm anterior from scleral spur), and scleral spur angle. Measurements were performed by masked, certified Reading Center graders using the Visante's Internal Measurement Tool. Differences in measurements between morning and afternoon, lighting variations, and angle of incidence were compared. Mean age of the participants was 31.2 years (range 23-58). Anterior chamber angle metrics did not differ significantly from morning to afternoon imaging, or when the angle of incidence was offset by 5° in either direction away from the inferior angle 6 o'clock position. (p-value 0.13-0.93). Angle metrics at the inferior corneal limbus, 6 o'clock position (IC270), with room lighting 'OFF', showed a significant decrease (p < 0.05) compared to room lighting 'ON'. There does not appear to be significant diurnal variation in AS-OCT parameters in normal individuals, but lighting conditions need to be strictly controlled since variation in lighting led to significant variability in AS-OCT parameters. No changes in ACA parameters were noted by varying the angle

  7. Beyond Euler angles: exploiting the angle-axis parametrization in a multipole expansion of the rotation operator.

    PubMed

    Siemens, Mark; Hancock, Jason; Siminovitch, David

    2007-02-01

    Euler angles (alpha,beta,gamma) are cumbersome from a computational point of view, and their link to experimental parameters is oblique. The angle-axis {Phi, n} parametrization, especially in the form of quaternions (or Euler-Rodrigues parameters), has served as the most promising alternative, and they have enjoyed considerable success in rf pulse design and optimization. We focus on the benefits of angle-axis parameters by considering a multipole operator expansion of the rotation operator D(Phi, n), and a Clebsch-Gordan expansion of the rotation matrices D(MM')(J)(Phi, n). Each of the coefficients in the Clebsch-Gordan expansion is proportional to the product of a spherical harmonic of the vector n specifying the axis of rotation, Y(lambdamu)(n), with a fixed function of the rotation angle Phi, a Gegenbauer polynomial C(2J-lambda)(lambda+1)(cosPhi/2). Several application examples demonstrate that this Clebsch-Gordan expansion gives easy and direct access to many of the parameters of experimental interest, including coherence order changes (isolated in the Clebsch-Gordan coefficients), and rotation angle (isolated in the Gegenbauer polynomials).

  8. Simple Map in Action-Angle Coordinates.

    NASA Astrophysics Data System (ADS)

    Kerwin, Olivia; Punjabi, Alkesh; Ali, Halima

    2008-04-01

    The simple map is the simplest map that has the topology of a divertor tokamak. The simple map has three canonical representations: (i) the natural coordinates - toroidal magnetic flux and poloidal angle (ψ,θ), (ii) the physical coordinates - the physical variables (R,Z) or (X,Y), and (iii) the action-angle coordinates - (J,θ) or magnetic coordinates (ψ, θ). All three are canonical coordinates for field lines. The simple map in the (X,Y) representation has been studied extensively ^1, 2. Here we analytically calculate the action-angle coordinates and safety factor q for the simple map. We construct the equilibrium generating function for the simple map in action-angle coordinates. We derive the simple map in action-angle representation, and calculate the stochastic broadening of the ideal separatrix due to topological noise in action-angle representation. We also show how the geometric effects such as elongation, the height, and width of the ideal separatrix surface can be investigated using a slight modification of the simple map in action-angle representation. This work is supported by the following grants US Department of Energy - OFES DE-FG02-01ER54624 and DE-FG02-04ER54793 and National Science Foundation - HRD-0630372 and 0411394. [1] A. Punjabi, H. Ali, T. Evans, and A. Boozer, Phys Lett A, 364 140-145 (2007). [2] A. Punjabi, A. Verma, and A. Boozer, Phys.Rev. Lett. 69, 3322 (1992).

  9. Ethnic differences in primary angle-closure glaucoma.

    PubMed

    Yip, Jennifer L Y; Foster, Paul J

    2006-04-01

    Observational studies from different countries have shown that populations of East Asian origin have a higher frequency of primary angle-closure glaucoma compared with those of European or African descent. As half of all cases of glaucoma reside in Asia, and with primary angle-closure glaucoma carrying a higher rate of visual morbidity, primary angle-closure glaucoma poses an important public health problem; however, the inconsistent use of techniques and definitions to detect and diagnose primary angle-closure glaucoma has resulted in difficulties in interpreting the accuracy and comparability of such data. Therefore it is important to review these studies in the light of a consistent classification system. There are increasing reports that support previous findings on the incidence and prevalence of primary angle-closure glaucoma in different ethnic groups. There have also been further investigations into the mechanism and natural history of primary angle-closure glaucoma in Asian populations. International investigations into primary angle-closure glaucoma have demonstrated reproducible evidence that ethnic variations do exist. Cross-sectional studies in this area have also suggested that differences in anterior chamber depth, together with its association with peripheral anterior synechiae, may be part of the underlying mechanism behind these differences. The ideas generated need to be further explored with longitudinal data of changes in anterior chamber depth and peripheral anterior synechiae in different populations. The detailed mechanisms behind the development of angle-closure and primary angle-closure glaucoma should also be investigated.

  10. Two Comments on Bond Angles

    NASA Astrophysics Data System (ADS)

    Glaister, P.

    1997-09-01

    Tetrahedral Bond Angle from Elementary Trigonometry The alternative approach of using the scalar (or dot) product of vectors enables the determination of the bond angle in a tetrahedral molecule in a simple way. There is, of course, an even more straightforward derivation suitable for students who are unfamiliar with vectors, or products thereof, but who do know some elementary trigonometry. The starting point is the figure showing triangle OAB. The point O is the center of a cube, and A and B are at opposite corners of a face of that cube in which fits a regular tetrahedron. The required bond angle alpha = AÔB; and using Pythagoras' theorem, AB = 2(square root 2) is the diagonal of a face of the cube. Hence from right-angled triangle OEB, tan(alpha/2) = (square root 2) and therefore alpha = 2tan-1(square root 2) is approx. 109° 28' (see Fig. 1).

  11. Effect of laser peripheral iridotomy on anterior chamber angle anatomy in primary angle closure spectrum eyes

    PubMed Central

    Kansara, Seema; Blieden, Lauren S.; Chuang, Alice Z.; Baker, Laura A.; Bell, Nicholas P.; Mankiewicz, Kimberly A.; Feldman, Robert M.

    2015-01-01

    Purpose To evaluate the change in trabecular-iris circumference volume (TICV) after laser peripheral iridotomy (LPI) in primary angle closure (PAC) spectrum eyes Patients and Methods Forty-two chronic PAC spectrum eyes from 24 patients were enrolled. Eyes with anterior chamber abnormalities affecting angle measurement were excluded. Intraocular pressure, slit lamp exam, and gonioscopy were recorded at each visit. Anterior segment optical coherence tomography (ASOCT) with 3D mode angle analysis scans were taken with the CASIA SS-1000 (Tomey Corp., Nagoya, Japan) before and after LPI. Forty-two pre-LPI ASOCT scans and 34 post-LPI ASOCT scans were analyzed using the Anterior Chamber Analysis and Interpretation (ACAI, Houston, TX) software. A mixed-effect model analysis was used to compare the trabecular-iris space area (TISA) changes among 4 quadrants, as well as to identify potential factors affecting TICV. Results There was a significant increase in all average angle parameters after LPI (TISA500, TISA750, TICV500, and TICV750). The magnitude of change in TISA500 in the superior angle was significantly less than the other angles. The changes in TICV500 and TICV750 were not associated with any demographic or ocular characteristics. Conclusion TICV is a useful parameter to quantitatively measure the effectiveness of LPI in the treatment of eyes with PAC spectrum disease. PMID:26066504

  12. Using Digital Technology to See Angles from Different Angles. Part 2: Openings and Turns

    ERIC Educational Resources Information Center

    Host, Erin; Baynham, Emily; McMaster, Heather

    2015-01-01

    Ever wondered how to use technology to teach angles? This article follows on from an earlier article published last year, providing a range of ideas for integrating technology and concrete materials with the teaching of angle concepts. The authors also provide a comprehensive list of free online games and learning objects that can be used to teach…

  13. Particle chaos and pitch angle scattering

    NASA Technical Reports Server (NTRS)

    Burkhart, G. R.; Dusenbery, P. B.; Speiser, T. W.

    1995-01-01

    Pitch angle scattering is a factor that helps determine the dawn-to-dusk current, controls particle energization, and it has also been used as a remote probe of the current sheet structure. Previous studies have interpreted their results under the exception that randomization will be greatest when the ratio of the two timescales of motion (gyration parallel to and perpendicular to the current sheet) is closet to one. Recently, the average expotential divergence rate (AEDR) has been calculated for particle motion in a hyperbolic current sheet (Chen, 1992). It is claimed that this AEDR measures the degree of chaos and therefore may be thought to measure the randomization. In contrast to previous expectations, the AEDR is not maximized when Kappa is approximately equal to 1 but instead increases with decreasing Kappa. Also contrary to previous expectations, the AEDR is dependent upon the parameter b(sub z). In response to the challenge to previous expectations that has been raised by this calculation of the AEDR, we have investigated the dependence of a measure of particle pitch angle scattering on both the parameters Kappa and b(sub z). We find that, as was previously expected, particle pitch angle scattering is maximized near Kappa = 1 provided that Kappa/b(sub z) greater than 1. In the opposite regime, Kappa/b(sub z) less than 1, we find that particle pitch angle scattering is still largest when the two timescales are equal, but the ratio of the timescales is proportional to b(sub z). In this second regime, particle pitch angle scattering is not due to randomization, but is instead due to a systematic pitch angle change. This result shows that particle pitch angle scattering need not be due to randomization and indicates how a measure of pitch angle scattering can exhibit a different behavior than a measure of chaos.

  14. Hallux valgus surgery may produce early improvements in balance control: results of a cross-sectional pilot study.

    PubMed

    Sadra, Saba; Fleischer, Adam; Klein, Erin; Grewal, Gurtej S; Knight, Jessica; Weil, Lowell Scott; Weil, Lowell; Najafi, Bijan

    2013-01-01

    Hallux valgus (HV) is associated with poorer performance during gait and balance tasks and is an independent risk factor for falls in older adults. We sought to assess whether corrective HV surgery improves gait and balance. Using a cross-sectional study design, gait and static balance data were obtained from 40 adults: 19 patients with HV only (preoperative group), 10 patients who recently underwent successful HV surgery (postoperative group), and 11 control participants. Assessments were made in the clinic using body-worn sensors. Patients in the preoperative group generally demonstrated poorer static balance control compared with the other two groups. Despite similar age and body mass index, postoperative patients exhibited 29% and 63% less center of mass sway than preoperative patients during double-and single-support balance assessments, respectively (analysis of variance P =.17 and P =.14, respectively [both eyes open condition]). Overall, gait performance was similar among the groups, except for speed during gait initiation, where lower speeds were encountered in the postoperative group compared with the preoperative group (Scheffe P = .049). This study provides supportive evidence regarding the benefits of corrective lower-extremity surgery on certain aspects of balance control. Patients seem to demonstrate early improvements in static balance after corrective HV surgery, whereas gait improvements may require a longer recovery time. Further research using a longitudinal study design and a larger sample size capable of assessing the long-term effects of HV surgical correction on balance and gait is probably warranted.

  15. Catecholamines profiles at diagnosis: Increased diagnostic sensitivity and correlation with biological and clinical features in neuroblastoma patients.

    PubMed

    Verly, Iedan R N; van Kuilenburg, André B P; Abeling, Nico G G M; Goorden, Susan M I; Fiocco, Marta; Vaz, Frédéric M; van Noesel, Max M; Zwaan, C Michel; Kaspers, GertJan L; Merks, Johannes H M; Caron, Huib N; Tytgat, Godelieve A M

    2017-02-01

    Neuroblastoma (NBL) accounts for 10% of the paediatric malignancies and is responsible for 15% of the paediatric cancer-related deaths. Vanillylmandelic acid (VMA) and homovanillic acid (HVA) are most commonly analysed in urine of NBL patients. However, their diagnostic sensitivity is suboptimal (82%). Therefore, we performed in-depth analysis of the diagnostic sensitivity of a panel of urinary catecholamine metabolites. Retrospective study of a panel of 8 urinary catecholamine metabolites (VMA, HVA, 3-methoxytyramine [3MT], dopamine, epinephrine, metanephrine, norepinephrine and normetanephrine [NMN]) from 301 NBL patients at diagnosis. Special attention was given to subgroups, metaiodobenzylguanidine (MIBG) non-avid tumours and VMA/HVA negative patients. Elevated catecholamine metabolites, especially 3MT, correlated with nine out of 12 NBL characteristics such as stage, age, MYCN amplification, loss of heterozygosity for 1p and bone-marrow invasion. The combination of the classical markers VMA and HVA had a diagnostic sensitivity of 84%. NMN was the most sensitive single diagnostic metabolite with overall sensitivity of 89%. When all 8 metabolites were combined, a diagnostic sensitivity of 95% was achieved. Among the VMA and HVA negative patients, were also 29% with stage 4 disease, which usually had elevation of other catecholamine metabolites (93%). Diagnostic sensitivity for patients with MIBG non-avid tumour was improved from 33% (VMA and/or HVA) to 89% by measuring the panel. Our study demonstrates that analysis of a urinary catecholamine metabolite panel, comprising 8 metabolites, ensures the highest sensitivity to diagnose NBL patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Pitch angle of galactic spiral arms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Michikoshi, Shugo; Kokubo, Eiichiro, E-mail: michiko@mail.doshisha.ac.jp, E-mail: kokubo@th.nao.ac.jp

    2014-06-01

    One of the key parameters that characterizes spiral arms in disk galaxies is a pitch angle that measures the inclination of a spiral arm to the direction of galactic rotation. The pitch angle differs from galaxy to galaxy, which suggests that the rotation law of galactic disks determines it. In order to investigate the relation between the pitch angle of spiral arms and the shear rate of galactic differential rotation, we perform local N-body simulations of pure stellar disks. We find that the pitch angle increases with the epicycle frequency and decreases with the shear rate and obtain the fittingmore » formula. This dependence is explained by the swing amplification mechanism.« less

  17. Gonioscopy in primary angle closure glaucoma.

    PubMed

    Bruno, Christina A; Alward, Wallace L M

    2002-06-01

    Primary angle closure is a condition characterized by obstruction to aqueous humor outflow by the peripheral iris, and results in changes in the iridocorneal angle that are visible through gonioscopic examination. Gonioscopy in these eyes, however, can be difficult. This chapter discusses techniques that might help in the examination. These include beginning the examination with the inferior angle, methods to help in looking over the iris, cycloplegia, locating the corneal wedge, indentation, van Herick estimation, examining the other eye, and topical glycerin. Finally, there is a discussion about the pathology associated with the closed angle, with emphasis on the appearance of iris bombé, plateau iris, and the distinction between iris processes and peripheral anterior synechiae.

  18. Contact angle distribution of particles at fluid interfaces.

    PubMed

    Snoeyink, Craig; Barman, Sourav; Christopher, Gordon F

    2015-01-27

    Recent measurements have implied a distribution of interfacially adsorbed particles' contact angles; however, it has been impossible to measure statistically significant numbers for these contact angles noninvasively in situ. Using a new microscopy method that allows nanometer-scale resolution of particle's 3D positions on an interface, we have measured the contact angles for thousands of latex particles at an oil/water interface. Furthermore, these measurements are dynamic, allowing the observation of the particle contact angle with high temporal resolution, resulting in hundreds of thousands of individual contact angle measurements. The contact angle has been found to fit a normal distribution with a standard deviation of 19.3°, which is much larger than previously recorded. Furthermore, the technique used allows the effect of measurement error, constrained interfacial diffusion, and particle property variation on the contact angle distribution to be individually evaluated. Because of the ability to measure the contact angle noninvasively, the results provide previously unobtainable, unique data on the dynamics and distribution of the adsorbed particles' contact angle.

  19. Correlations between Preoperative Angle Parameters and Postoperative Unpredicted Refractive Errors after Cataract Surgery in Open Angle Glaucoma (AOD 500).

    PubMed

    Lee, Wonseok; Bae, Hyoung Won; Lee, Si Hyung; Kim, Chan Yun; Seong, Gong Je

    2017-03-01

    To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery with open angle glaucoma (OAG) and to identify preoperative angle parameters correlated with postoperative unpredicted refractive errors. This study comprised 45 eyes from 45 OAG subjects and 63 eyes from 63 non-glaucomatous cataract subjects (controls). We investigated differences in preoperative predicted refractive errors and postoperative refractive errors for each group. Preoperative predicted refractive errors were obtained by biometry (IOL-master) and compared to postoperative refractive errors measured by auto-refractometer 2 months postoperatively. Anterior angle parameters were determined using swept source optical coherence tomography. We investigated correlations between preoperative angle parameters [angle open distance (AOD); trabecular iris surface area (TISA); angle recess area (ARA); trabecular iris angle (TIA)] and postoperative unpredicted refractive errors. In patients with OAG, significant differences were noted between preoperative predicted and postoperative real refractive errors, with more myopia than predicted. No significant differences were recorded in controls. Angle parameters (AOD, ARA, TISA, and TIA) at the superior and inferior quadrant were significantly correlated with differences between predicted and postoperative refractive errors in OAG patients (-0.321 to -0.408, p<0.05). Superior quadrant AOD 500 was significantly correlated with postoperative refractive differences in multivariate linear regression analysis (β=-2.925, R²=0.404). Clinically unpredicted refractive errors after cataract surgery were more common in OAG than in controls. Certain preoperative angle parameters, especially AOD 500 at the superior quadrant, were significantly correlated with these unpredicted errors.

  20. Optimum take-off angle in the long jump.

    PubMed

    Linthorne, Nicholas P; Guzman, Maurice S; Bridgett, Lisa A

    2005-07-01

    In this study, we found that the optimum take-off angle for a long jumper may be predicted by combining the equation for the range of a projectile in free flight with the measured relations between take-off speed, take-off height and take-off angle for the athlete. The prediction method was evaluated using video measurements of three experienced male long jumpers who performed maximum-effort jumps over a wide range of take-off angles. To produce low take-off angles the athletes used a long and fast run-up, whereas higher take-off angles were produced using a progressively shorter and slower run-up. For all three athletes, the take-off speed decreased and the take-off height increased as the athlete jumped with a higher take-off angle. The calculated optimum take-off angles were in good agreement with the athletes' competition take-off angles.

  1. Ring magnet firing angle control

    DOEpatents

    Knott, M.J.; Lewis, L.G.; Rabe, H.H.

    1975-10-21

    A device is provided for controlling the firing angles of thyratrons (rectifiers) in a ring magnet power supply. A phase lock loop develops a smooth ac signal of frequency equal to and in phase with the frequency of the voltage wave developed by the main generator of the power supply. A counter that counts from zero to a particular number each cycle of the main generator voltage wave is synchronized with the smooth AC signal of the phase lock loop. Gates compare the number in the counter with predetermined desired firing angles for each thyratron and with coincidence the proper thyratron is fired at the predetermined firing angle.

  2. A thermodynamic model of contact angle hysteresis.

    PubMed

    Makkonen, Lasse

    2017-08-14

    When a three-phase contact line moves along a solid surface, the contact angle no longer corresponds to the static equilibrium angle but is larger when the liquid is advancing and smaller when the liquid is receding. The difference between the advancing and receding contact angles, i.e., the contact angle hysteresis, is of paramount importance in wetting and capillarity. For example, it determines the magnitude of the external force that is required to make a drop slide on a solid surface. Until now, fundamental origin of the contact angle hysteresis has been controversial. Here, this origin is revealed and a quantitative theory is derived. The theory is corroborated by the available experimental data for a large number of solid-liquid combinations. The theory is applied in modelling the contact angle hysteresis on a textured surface, and these results are also in quantitative agreement with the experimental data.

  3. Solar cell angle of incidence corrections

    NASA Technical Reports Server (NTRS)

    Burger, Dale R.; Mueller, Robert L.

    1995-01-01

    Literature on solar array angle of incidence corrections was found to be sparse and contained no tabular data for support. This lack along with recent data on 27 GaAs/Ge 4 cm by 4 cm cells initiated the analysis presented in this paper. The literature cites seven possible contributors to angle of incidence effects: cosine, optical front surface, edge, shadowing, UV degradation, particulate soiling, and background color. Only the first three are covered in this paper due to lack of sufficient data. The cosine correction is commonly used but is not sufficient when the incident angle is large. Fresnel reflection calculations require knowledge of the index of refraction of the coverglass front surface. The absolute index of refraction for the coverglass front surface was not known nor was it measured due to lack of funds. However, a value for the index of refraction was obtained by examining how the prediction errors varied with different assumed indices and selecting the best fit to the set of measured values. Corrections using front surface Fresnel reflection along with the cosine correction give very good predictive results when compared to measured data, except there is a definite trend away from predicted values at the larger incident angles. This trend could be related to edge effects and is illustrated by a use of a box plot of the errors and by plotting the deviation of the mean against incidence angle. The trend is for larger deviations at larger incidence angles and there may be a fourth order effect involved in the trend. A chi-squared test was used to determine if the measurement errors were normally distributed. At 10 degrees the chi-squared test failed, probably due to the very small numbers involved or a bias from the measurement procedure. All other angles showed a good fit to the normal distribution with increasing goodness-of-fit as the angles increased which reinforces the very small numbers hypothesis. The contributed data only went to 65 degrees

  4. Spectral data of specular reflectance, narrow-angle transmittance and angle-resolved surface scattering of materials for solar concentrators.

    PubMed

    Good, Philipp; Cooper, Thomas; Querci, Marco; Wiik, Nicolay; Ambrosetti, Gianluca; Steinfeld, Aldo

    2016-03-01

    The spectral specular reflectance of conventional and novel reflective materials for solar concentrators is measured with an acceptance angle of 17.5 mrad over the wavelength range 300-2500 nm at incidence angles 15-60° using a spectroscopic goniometry system. The same experimental setup is used to determine the spectral narrow-angle transmittance of semi-transparent materials for solar collector covers at incidence angles 0-60°. In addition, the angle-resolved surface scattering of reflective materials is recorded by an area-scan CCD detector over the spectral range 350-1050 nm. A comprehensive summary, discussion, and interpretation of the results are included in the associated research article "Spectral reflectance, transmittance, and angular scattering of materials for solar concentrators" in Solar Energy Materials and Solar Cells.

  5. Deflection angle detecting system for the large-angle and high-linearity fast steering mirror using quadrant detector

    NASA Astrophysics Data System (ADS)

    Ni, Yingxue; Wu, Jiabin; San, Xiaogang; Gao, Shijie; Ding, Shaohang; Wang, Jing; Wang, Tao

    2018-02-01

    A deflection angle detecting system (DADS) using a quadrant detector (QD) is developed to achieve the large deflection angle and high linearity for the fast steering mirror (FSM). The mathematical model of the DADS is established by analyzing the principle of position detecting and error characteristics of the QD. Based on this mathematical model, the method of optimizing deflection angle and linearity of FSM is demonstrated, which is proved feasible by simulation and experimental results. Finally, a QD-based FSM is designed and tested. The results show that it achieves 0.72% nonlinearity, ±2.0 deg deflection angle, and 1.11-μrad resolution. Therefore, the application of this method will be beneficial to design the FSM.

  6. A gallery approach for off-angle iris recognition

    NASA Astrophysics Data System (ADS)

    Karakaya, Mahmut; Yoldash, Rashiduddin; Boehnen, Christopher

    2015-05-01

    It has been proven that hamming distance score between frontal and off-angle iris images of same eye differs in iris recognition system. The distinction of hamming distance score is caused by many factors such as image acquisition angle, occlusion, pupil dilation, and limbus effect. In this paper, we first study the effect of the angle variations between iris plane and the image acquisition systems. We present how hamming distance changes for different off-angle iris images even if they are coming from the same iris. We observe that increment in acquisition angle of compared iris images causes the increment in hamming distance. Second, we propose a new technique in off-angle iris recognition system that includes creating a gallery of different off-angle iris images (such as, 0, 10, 20, 30, 40, and 50 degrees) and comparing each probe image with these gallery images. We will show the accuracy of the gallery approach for off-angle iris recognition.

  7. The Dual-Angle Method for Fast, Sensitive T1 Measurement in Vivo with Low-Angle Adiabatic Pulses

    NASA Astrophysics Data System (ADS)

    Bottomley, P. A.; Ouwerkerk, R.

    A new method for measuring T1 based on a measurement of the ratio, R, of the steady-state partially saturated NMR signals acquired at two fixed low flip angles (<90°) and a single sequence-repetition period, TR, is presented, The flip angles are chosen to optimize both the signal-to-noise ratio per unit time relative to the best possible Ernst-angle performance and the sensitivity with which a measurement of R can resolve differences in T1. A flip-angle pair at of around (60°, 15°) yields 70-79% of the maximum achievable Ernst-angle signal-to-noise ratio and a near-linear dependence of R on TR/ T1 with gradient of about 2:1 over the range 0.1 ≤ TR/ T1 ≤ 1. Errors in hip-angle and excitation-field ( B1) inhomogeneity result in roughly proportionate errors in the apparent T1. The method is best implemented with adiabatic low-angle pulses such as B1-independent rotation (BIR-4) or BIR-4 phase-cycled (BIRP) pulses, which permit measurements with surface coils. Experimental validation was obtained at 2 T by comparison of unlocalized inversion-recovery and dual-angle proton ( 1H) and phosphorus ( 31P) measurements from vials containing doped water with 0.04 ≤ T1 ≤ 2.8 s and from the metabolites in the calf muscles of eight human volunteers. Calf muscle values of 6 ± 0.5 s for phosphocreatine and around 3.7 ± 0.8 s for the adenosine triphosphates (ATP) were in good agreement with inversion-recovery T1 values and values from the literature. Use of the dual-angle method accelerated T1 measurement time by about fivefold over inversion recovery. The dual-angle method was implemented in a one-dimensional localized surface-coil 31P spectroscopy sequence, producing consistent T1 measurements from phantoms, the calf muscle, and the human liver. 31P T1 values of ATP in the livers of six volunteers were about 0.5 ± 0.1 to 0.6 ± 0.2 s: the total exam times were about 35 minutes per subject. The method is ideally suited to low-sensitivity and/or low

  8. Correlations between Preoperative Angle Parameters and Postoperative Unpredicted Refractive Errors after Cataract Surgery in Open Angle Glaucoma (AOD 500)

    PubMed Central

    Lee, Wonseok; Bae, Hyoung Won; Lee, Si Hyung; Kim, Chan Yun

    2017-01-01

    Purpose To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery with open angle glaucoma (OAG) and to identify preoperative angle parameters correlated with postoperative unpredicted refractive errors. Materials and Methods This study comprised 45 eyes from 45 OAG subjects and 63 eyes from 63 non-glaucomatous cataract subjects (controls). We investigated differences in preoperative predicted refractive errors and postoperative refractive errors for each group. Preoperative predicted refractive errors were obtained by biometry (IOL-master) and compared to postoperative refractive errors measured by auto-refractometer 2 months postoperatively. Anterior angle parameters were determined using swept source optical coherence tomography. We investigated correlations between preoperative angle parameters [angle open distance (AOD); trabecular iris surface area (TISA); angle recess area (ARA); trabecular iris angle (TIA)] and postoperative unpredicted refractive errors. Results In patients with OAG, significant differences were noted between preoperative predicted and postoperative real refractive errors, with more myopia than predicted. No significant differences were recorded in controls. Angle parameters (AOD, ARA, TISA, and TIA) at the superior and inferior quadrant were significantly correlated with differences between predicted and postoperative refractive errors in OAG patients (-0.321 to -0.408, p<0.05). Superior quadrant AOD 500 was significantly correlated with postoperative refractive differences in multivariate linear regression analysis (β=-2.925, R2=0.404). Conclusion Clinically unpredicted refractive errors after cataract surgery were more common in OAG than in controls. Certain preoperative angle parameters, especially AOD 500 at the superior quadrant, were significantly correlated with these unpredicted errors. PMID:28120576

  9. Anterior chamber angle assessment using gonioscopy and ultrasound biomicroscopy.

    PubMed

    Narayanaswamy, Arun; Vijaya, Lingam; Shantha, B; Baskaran, Mani; Sathidevi, A V; Baluswamy, Sukumar

    2004-01-01

    Comparison of anterior chamber angle measurements using ultrasound biomicroscopy (UBM) and gonioscopy. Five hundred subjects were evaluated for grading of angle width by the Shaffer method. UBM was done in the same group to document angle width, angle opening distance (AOD 500), and anterior chamber depth. Biometric parameters were documented in all subjects. UBM and gonioscopic findings were compared. A study was conducted in 282 men and 218 women with a mean age of 57.32 +/- 12.48 years. Gonioscopic grading was used to segregate occludable (slit-like, grades 1 and 2) from nonoccludable (grades 3 and 4) angles. Subjective assessment by gonioscopy resulted in an overestimation of angle width within the occludable group when compared with values obtained by UBM. This did not affect the segregation of occludable versus nonoccludable angles by gonioscopy. Biometric parameters in eyes with occludable angles were significantly lower in comparison with eyes with nonoccludable angles, except for lens thickness. AOD 500 correlated well with angle width. We concluded that clinical segregation into occludable and nonoccludable angles by an experienced observer using gonioscopy is fairly accurate. However, UBM is required for objective quantification of angles, and AOD 500 can be a reliable and standard parameter to grade angle width.

  10. [Visual cuing effect for haptic angle judgment].

    PubMed

    Era, Ataru; Yokosawa, Kazuhiko

    2009-08-01

    We investigated whether visual cues are useful for judging haptic angles. Participants explored three-dimensional angles with a virtual haptic feedback device. For visual cues, we use a location cue, which synchronizes haptic exploration, and a space cue, which specifies the haptic space. In Experiment 1, angles were judged more correctly with both cues, but were overestimated with a location cue only. In Experiment 2, the visual cues emphasized depth, and overestimation with location cues occurred, but space cues had no influence. The results showed that (a) when both cues are presented, haptic angles are judged more correctly. (b) Location cues facilitate only motion information, and not depth information. (c) Haptic angles are apt to be overestimated when there is both haptic and visual information.

  11. Recent Biologic Studies on Suicide.

    ERIC Educational Resources Information Center

    Roy, Alex

    1994-01-01

    Reviews studies on suicidal behavior in depressed patients, including study showing that depressed patients who had attempted suicide had significantly reduced CSF concentrations of dopamine metabolite homovanillic acid (HVA) and significantly lower urinary outputs of HVA than patients who had not attempted suicide. Considers role of diminished…

  12. Angle imaging: Advances and challenges

    PubMed Central

    Quek, Desmond T L; Nongpiur, Monisha E; Perera, Shamira A; Aung, Tin

    2011-01-01

    Primary angle closure glaucoma (PACG) is a major form of glaucoma in large populous countries in East and South Asia. The high visual morbidity from PACG is related to the destructive nature of the asymptomatic form of the disease. Early detection of anatomically narrow angles is important and the subsequent prevention of visual loss from PACG depends on an accurate assessment of the anterior chamber angle (ACA). This review paper discusses the advantages and limitations of newer ACA imaging technologies, namely ultrasound biomicroscopy, Scheimpflug photography, anterior segment optical coherence tomography and EyeCam, highlighting the current clinical evidence comparing these devices with each other and with clinical dynamic indentation gonioscopy, the current reference standard. PMID:21150037

  13. Understanding Angle and Angle Measure: A Design-Based Research Study Using Context Aware Ubiquitous Learning

    ERIC Educational Resources Information Center

    Crompton, Helen

    2015-01-01

    Mobile technologies are quickly becoming tools found in the educational environment. The researchers in this study use a form of mobile learning to support students in learning about angle concepts. Design-based research is used in this study to develop an empirically-substantiated local instruction theory about students' develop of angle and…

  14. Definition, transformation-formulae and measurements of tipvane angles

    NASA Astrophysics Data System (ADS)

    Bruining, A.

    1987-10-01

    The theoretical background of different angle systems used to define tipvane attitude in 3-D space is outlined. Different Euler equations are used for the various, wind tunnel, towing tank, and full scale tipvane models. The influence of rotor blade flapping angle on tipvane angles is described. The tipvane attitude measuring method is outlined in relationship to the Euler angle system. Side effects on the angle of attack of the tipvane due to rotation, translation, and curving of the tipvane are described.

  15. Neurochemical variables in schizophrenic patients during switching from neuroleptics to clozapine.

    PubMed

    Hatzimanolis, J; Lykouras, L; Markianos, M; Oulis, P

    1998-10-01

    1. The study aimed to search for the effect of clozapine on the levels of the main metabolites of dopamine homovanillic acid (HVA), serotonin 5-hydroxyindoleacetic acid (5-HIAA) and norepinephrine 3-methoxy-4-hydroxyphenylglycol (MHPG) in urine as well as on plasma levels of HVA, 5-HIAA, prolactin (PRL) and cortisol. 2. Seventeen male patients diagnosed as suffering from DSM-IIIR schizophrenia completed the study. 3. The patients were switched from classical antipsychotics to clozapine. After six weeks treatment with clozapine the severity of psychopathology (total BPRS score) decreased significantly (p = 0.00004). pHVA and -5-HIAA did not change significantly. uMHPG increased significantly (p = 0.017). Both PRL and cortisol levels decreased significantly (p = 0.0002, p = 0.032 respectively). Patients with high HVA levels in both plasma and urine at baseline had a lower BPRS score at the end of treatment period (p = 0.0001, p = 0.049 respectively).

  16. Association of plasma homovanillic acid with behavioral symptoms in patients diagnosed with dementia: a preliminary report.

    PubMed

    Sweet, R A; Pollock, B G; Mulsant, B H; Rosen, J; Lo, K H; Yao, J K; Henteleff, R A; Mazumdar, S

    1997-12-01

    Neuroleptic treatment of psychotic symptoms or agitated behavior in elderly patients diagnosed with dementia is associated with reduced efficacy and increased rates of neuroleptic-induced parkinsonism in comparison to younger patients with schizophrenia. We report the first study to examine the relationship between an in vivo measure of dopaminergic function, plasma homovanillic acid (pHVA), and ratings of psychosis, agitation, and parkinsonism before and after neuroleptic treatment in dementia patients. Pretreatment pHVA was significantly correlated with parkinsonian rigidity, with a trend observed with agitation and hostility. Though mean pHVA did not change during perphenazine treatment, intraindividual change in pHVA at day 15 was correlated with improvement in hostility, with a similar trend for improvement in agitation. These preliminary findings are consistent with reports associating dopaminergic function with agitated, but not psychotic, symptoms in patients diagnosed with dementia, and with a reduced responsivity of dopaminergic systems to neuroleptic treatment in these patients.

  17. An Anatomic Study on Whether the Immature Patella is Centered on an Anteroposterior Radiograph.

    PubMed

    Kyriakedes, James C; Liu, Raymond W

    2017-03-01

    In the operating room, after first obtaining a proper lateral radiograph with the condyles superimposed, a 90-degree rotation of the intraoperative fluoroscopy unit does not always produce an anteroposterior (AP) image with the patella centered. The orthogonality of these 2 views has not been well determined in children. This study was comprised of a radiographic group (35 knees) and a cadaveric group (59 knees). Both cadaveric and clinical images were obtained by resting or positioning the femur with the posterior condyles overlapped, and then taking an orthogonal AP image. Centering of the patella was calculated and multiple regression analysis was performed to determine the relationship between patellar centering and age, sex, ethnicity, mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle (MPTA), and contralateral centering. Mean patellar centering, expressed as the lateral position of the patella with respect to the total condylar width, was 0.08±0.10 in the radiographic group and 0.06±0.03 in the cadaveric group. Positive (lateral) patellar centering in 1 knee had a statistically significant correlation with positive patellar centering in the contralateral knee in both the radiographs and the cadavers. In the radiographic group, there was a statistically significant correlation between femoral varus and valgus deformities and positive patellar centering. In the cadaveric group, there was a statistically significant correlation between tibial valgus and negative (medial) patellar centering. The patella in an immature knee is rarely perfectly centered on a true AP image, and is usually seated slightly laterally within the femoral condyles. Obtaining a true AP intraoperative radiograph is critical to analyzing and correcting valgus and varus deformities, and in the proper placement of implants. When addressing knee deformity one should consider obtaining an AP view orthogonal either to a perfect lateral of the knee or orthogonal to the

  18. Physiological response of wild rainbow trout to angling: Impact of angling duration, fish size, body condition, and temperature

    USGS Publications Warehouse

    Meka, Julie M.; McCormick, S.D.

    2005-01-01

    This study evaluated the immediate physiological response of wild rainbow trout to catch-and-release angling in the Alagnak River, southwest Alaska. Information was recorded on individual rainbow trout (n = 415) captured by angling including landing time and the time required to remove hooks (angling duration), the time to anesthetize fish in clove oil and withdraw blood, fish length and weight, and water temperature at capture locations. Plasma cortisol, glucose, ions (sodium, potassium, chloride), and lactate were analyzed to determine the effects of angling duration, fish size, body condition, and temperature. Levels of plasma ions did not change significantly during the observed physiological response and levels of plasma glucose were sometimes influenced by length (2000, 2001), body condition (2001), or temperature (2001). Levels of plasma cortisol and lactate in extended capture fish (angling duration greater than 2 min) were significantly higher than levels in rapid capture fish (angling duration less than 2 min). Rapid capture fish were significantly smaller than extended capture fish, reflecting that fish size influenced landing and handling times. Fish size was related to cortisol and lactate in 2002, which corresponded to the year when larger fish were captured and there were longer landing times. Body condition (i.e., weight/length regression residuals index), was significantly related to lactate in 2000 and 2001. Water temperatures were higher in 2001 (mean temperature ± S.E., 13 ± 2oC) than in 2002 (10 ± 2oC), and fish captured in 2001 had significantly higher cortisol and lactate concentrations than fish captured in 2002. The pattern of increase in plasma cortisol and lactate was due to the amount of time fish were angled, and the upper limit of the response was due to water temperature. The results of this study indicate the importance of minimizing the duration of angling in order to reduce the sublethal physiological disturbances in wild

  19. Gimbal-Angle Vectors of the Nonredundant CMG Cluster

    NASA Astrophysics Data System (ADS)

    Lee, Donghun; Bang, Hyochoong

    2018-05-01

    This paper deals with the method using the preferred gimbal angles of a control moment gyro (CMG) cluster for controlling spacecraft attitude. To apply the method to the nonredundant CMG cluster, analytical gimbal-angle solutions for the zero angular momentum state are derived, and the gimbal-angle vectors for the nonzero angular momentum states are studied by a numerical method. It will be shown that the number of the gimbal-angle vectors is determined from the given skew angle and the angular momentum state of the CMG cluster. Through numerical examples, it is shown that the method using the preferred gimbal-angle is an efficient approach to avoid internal singularities for the nonredundant CMG cluster.

  20. Ocular Biometrics of Myopic Eyes With Narrow Angles.

    PubMed

    Chong, Gabriel T; Wen, Joanne C; Su, Daniel Hsien-Wen; Stinnett, Sandra; Asrani, Sanjay

    2016-02-01

    The purpose of this study was to compare the ocular biometrics between myopic patients with and without narrow angles. Patients with a stable myopic refraction (myopia worse than -1.00 D spherical equivalent) were prospectively recruited. Angle status was assessed using gonioscopy and biometric measurements were performed using an anterior segment optical coherence tomography and an IOLMaster. A total of 29 patients (58 eyes) were enrolled with 13 patients (26 eyes) classified as having narrow angles and 16 patients (32 eyes) classified as having open angles. Baseline demographics of age, sex, and ethnicity did not differ significantly between the 2 groups. The patients with narrow angles were on average older than those with open angles but the difference did not reach statistical significance (P=0.12). The central anterior chamber depth was significantly less in the eyes with narrow angles (P=0.05). However, the average lens thickness, although greater in the eyes with narrow angles, did not reach statistical significance (P=0.10). Refractive error, axial lengths, and iris thicknesses did not differ significantly between the 2 groups (P=0.32, 0.47, 0.15). Narrow angles can occur in myopic eyes. Routine gonioscopy is therefore recommended for all patients regardless of refractive error.

  1. Wide-angle imaging system with fiberoptic components providing angle-dependent virtual material stops

    NASA Technical Reports Server (NTRS)

    Vaughan, Arthur H. (Inventor)

    1993-01-01

    A strip imaging wide angle optical system is provided. The optical system is provided with a 'virtual' material stop to avoid aberrational effects inherent in wide angle optical systems. The optical system includes a spherical mirror section for receiving light from a 180 deg strip or arc of a target image. Light received by the spherical mirror section is reflected to a frustoconical mirror section for subsequent rereflection to a row of optical fibers. Each optical fiber transmits a portion of the received light to a detector. The optical system exploits the narrow cone of acceptance associated with optical fibers to substantially eliminate vignetting effects inherent in wide angle systems. Further, the optical system exploits the narrow cone of acceptance of the optical fibers to substantially limit spherical aberration. The optical system is ideally suited for any application wherein a 180 deg strip image need be detected, and is particularly well adapted for use in hostile environments such as in planetary exploration.

  2. Evidence for Ordering of Alzheimer’s Disease Biomarkers

    PubMed Central

    Jack, Clifford R.; Vemuri, Prashanthi; Wiste, Heather J.; Weigand, Stephen D.; Aisen, Paul S.; Trojanowski, John Q.; Shaw, Leslie M.; Bernstein, Matthew A.; Petersen, Ronald C.; Weiner, Michael W.

    2012-01-01

    Objective To empirically assess the concept that Alzheimer’s disease (AD) biomarkers significantly depart from normality in a temporally ordered manner. Design Validation sample Setting Multi-site, referral centers Patients We studied 401 elderly cognitively normal (CN), Mild Cognitive Impairment (MCI) and AD dementia subjects from the Alzheimer’s Disease Neuroimaging Initiative. We compared the proportions of three AD biomarkers – CSF Aβ42, CSF total tau (t-tau), and hippocampal volume adjusted by intra-cranial volume (HVa) - that were abnormal as cognitive impairment worsened. Cut-points demarcating normal vs. abnormal for each biomarker were established by maximizing diagnostic accuracy in independent autopsy samples. Interventions None Main Outcome measures AD biomarkers Results Within each clinical group in the entire sample (n=401) CSF Aβ42 was abnormal more often than t-tau or HVa. Among the 298 subjects with both baseline and 12 month data, the proportion of subjects with abnormal Aβ42 did not change from baseline to 12 months in any group. The proportion of subjects with abnormal t-tau increased from baseline to 12 months in CN (p=0.05) but not in MCI or dementia. In 209 subjects with abnormal CSF AB42 at baseline, the percent abnormal HVa, but not t-tau, increased from baseline to 12 months in MCI. Conclusions Reduction in CSF Aβ42 denotes a pathophysiological process that significantly departs from normality (i.e., becomes dynamic) early, while t-tau and HVa are biomarkers of downstream pathophysiological processes. T-tau becomes dynamic before HVa, but HVa is more dynamic in the clinically symptomatic MCI and dementia phases of the disease than t-tau. PMID:21825215

  3. Tachometer Derived From Brushless Shaft-Angle Resolver

    NASA Technical Reports Server (NTRS)

    Howard, David E.; Smith, Dennis A.

    1995-01-01

    Tachometer circuit operates in conjunction with brushless shaft-angle resolver. By performing sequence of straightforward mathematical operations on resolver signals and utilizing simple trigonometric identity, generates voltage proportional to rate of rotation of shaft. One advantage is use of brushless shaft-angle resolver as main source of rate signal: no brushes to wear out, no brush noise, and brushless resolvers have proven robustness. No switching of signals to generate noise. Another advantage, shaft-angle resolver used as shaft-angle sensor, tachometer input obtained without adding another sensor. Present circuit reduces overall size, weight, and cost of tachometer.

  4. Evaluation of the Microsoft Kinect for screening ACL injury.

    PubMed

    Stone, Erik E; Butler, Michael; McRuer, Aaron; Gray, Aaron; Marks, Jeffrey; Skubic, Marjorie

    2013-01-01

    A study was conducted to evaluate the use of the skeletal model generated by the Microsoft Kinect SDK in capturing four biomechanical measures during the Drop Vertical Jump test. These measures, which include: knee valgus motion from initial contact to peak flexion, frontal plane knee angle at initial contact, frontal plane knee angle at peak flexion, and knee-to-ankle separation ratio at peak flexion, have proven to be useful in screening for future knee anterior cruciate ligament (ACL) injuries among female athletes. A marker-based Vicon motion capture system was used for ground truth. Results indicate that the Kinect skeletal model likely has acceptable accuracy for use as part of a screening tool to identify elevated risk for ACL injury.

  5. Multiple incidence angle SIR-B experiment over Argentina

    NASA Technical Reports Server (NTRS)

    Cimino, Jobea; Casey, Daren; Wall, Stephen; Brandani, Aldo; Domik, Gitta; Leberl, Franz

    1986-01-01

    The Shuttle Imaging Radar (SIR-B), the second synthetic aperture radar (SAR) to fly aboard a shuttle, was launched on October 5, 1984. One of the primary goals of the SIR-B experiment was to use multiple incidence angle radar images to distinguish different terrain types through the use of their characteristic backscatter curves. This goal was accomplished in several locations including the Chubut Province of southern Argentina. Four descending image acquisitions were collected providing a multiple incidence angle image set. The data were first used to assess stereo-radargrammetric techniques. A digital elevation model was produced using the optimum pair of multiple incidence angle images. This model was then used to determine the local incidence angle of each picture element to generate curves of relative brightness vs. incidence angle. Secondary image products were also generated using the multi-angle data. The results of this work indicate that: (1) various forest species and various structures of a single species may be discriminated using multiple incidence angle radar imagery, and (2) it is essential to consider the variation in backscatter due to a variable incidence angle when analyzing and comparing data collected at varying frequencies and polarizations.

  6. Phase-angle controller for Stirling engines

    NASA Technical Reports Server (NTRS)

    Mcdougal, A. R. (Inventor)

    1980-01-01

    An actuator includes a restraint link adapted to be connected with a pivotal carrier arm for a force transfer gear interposed between the crankshaft for an expander portion of a Stirling engine and a crankshaft for the displacer portion of the engine. The restraint link is releasably trapped hydraulic fluid for selectively establishing a phase angle relationship between the crankshaft. A second embodiment incorporates a hydraulic coupler for use in varying the phase angle of gear-coupled crank fpr a Stirling engine whereby phase angle changes are obtainable.

  7. Preferred nasolabial angle in Middle Eastern population.

    PubMed

    Alharethy, Sami

    2017-05-01

    To define the preferred nasolabial angle measurement in Middle Eastern population. An observational study was conducted from January 2012 to January 2016 at the Department of Otolaryngology, Head and Neck Surgery, King Abdulaziz University Hospital, King Saud University, Riyadh, Kingdom of Saudi Arabia. A total of 1027 raters, 506 males, and 521 females were asked to choose the most ideal nasolabial angle for 5 males and 5 females lateral photographs whose nasolabial angle were modified with Photoshop into the following angles (85°, 90°, 95°, 100°, 105°, and 110°). Male raters preferred the angle of 89.5° ± 3.5° (mean ± SD) for males and 90.8° ± 5.6° for females. While female raters preferred the angle of 89.3° ± 3.8° for males and 90.5° ± 4.8° for females. ANOVA test compare means among groups: p: 0.342, and there is no statistically significant difference between groups. The results of our study showed an even more acute angles than degrees found in the literature. It shows that what young generation in our region prefers and clearly reflects that what could be explained as under rotation of the nasal tip in other cultures is just the ideal for some Middle Eastern population.

  8. Risk factors for suicide among patients with schizophrenia: a cohort study focused on cerebrospinal fluid levels of homovanillic acid and 5-hydroxyindoleacetic acid

    PubMed Central

    Neider, Daniel; Lindström, Leif H; Bodén, Robert

    2016-01-01

    Background The objective of this study was to investigate the association between 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) in cerebrospinal fluid (CSF), bullying, and later suicide among patients with schizophrenia. Methods Ninety-nine patients with schizophrenia were included. Correlations of clinical factors, 5-HIAA and HVA, and later suicide were investigated. Results Twelve patients committed suicide (12%) during a 28-year follow-up period. Later suicide was correlated to bullying in childhood (P=0.02) and a lower quotient of HVA/5-HIAA in CSF (P<0.05). Conclusion Suicide in schizophrenia is related to childhood exposedness and CSF neurotransmitter levels. PMID:27468235

  9. Normal Q-angle in an adult Nigerian population.

    PubMed

    Omololu, Bade B; Ogunlade, Olusegun S; Gopaldasani, Vinod K

    2009-08-01

    The Q-angle has been studied among the adult Caucasian population with the establishment of reference values. Scientists are beginning to accept the concept of different human races. Physical variability exists between various African ethnic groups and Caucasians as exemplified by differences in anatomic features such as a flat nose compared with a pointed nose, wide rather than narrow faces, and straight rather than curly hair. Therefore, we cannot assume the same Q-angle values will be applicable to Africans and Caucasians. We established a baseline reference value for normal Q-angles among asymptomatic Nigerian adults. The Q-angles of the left and right knees were measured using a goniometer in 477 Nigerian adults (354 males; 123 females) in the supine and standing positions. The mean Q-angles for men were 10.7 degrees +/- 2.2 degrees in the supine position and 12.3 degrees +/- 2.2 degrees in the standing position in the right knee. The left knee Q-angles in men were 10.5 degrees +/- 2.6 degrees in the supine position and 11.7 degrees +/- 2.8 degrees in the standing position. In women, the mean Q-angles for the right knee were 21 degrees +/- 4.8 degrees in the supine position and 22.8 degrees +/- 4.7 degrees in the standing position. The mean Q-angles for the left knee in women were 20.9 degrees +/- 4.6 degrees in the supine position and 22.7 degrees +/- 4.6 degrees in the standing position. We observed a difference in Q-angles in the supine and standing positions for all participants. The Q-angle in adult Nigerian men is comparable to that of adult Caucasian men, but the Q-angle of Nigerian women is greater than that of their Caucasian counterparts.

  10. Can orbital angle morphology distinguish dogs from wolves?

    PubMed

    Janssens, Luc; Spanoghe, Inge; Miller, Rebecca; Van Dongen, Stefan

    For more than a century, the orbital angle has been studied by many authors to distinguish dog skulls from their progenitor, the wolf. In early studies, the angle was reported to be different between dogs (49°-55°) and wolves (39°-46°). This clear difference was, however, questioned in a more recent Scandinavian study that shows some overlap. It is clear that in all studies several methodological issues were unexplored or unclear and that group sizes and the variety of breeds and wolf subspecies were small. Archaeological dog skulls had also not been studied. Our goal was to test larger and more varied groups and add archaeological samples as they are an evolutionary stage between wolves and modern dogs. We also tested the influence of measuring methods, intra- and inter-reliability, angle symmetry, the influence of variations in skull position and the possibility of measuring and comparing this angle on 3D CT scan images. Our results indicate that there is about 50 % overlap between the angle range in wolves and modern dogs. However, skulls with a very narrow orbital angle were only found in wolves and those with a very wide angle only in dogs. Archaeological dogs have a mean angle very close to the one of the wolves. Symmetry is highest in wolves and lowest in archaeological dogs. The measuring method is very reliable, for both inter- and intra-reliability (0.99-0.97), and most skull position changes have no statistical influence on the angle measured. Three-dimensional CT scan images can be used to measure OA, but the angles differ from direct measuring and cannot be used for comparison. Evolutionary changes in dog skulls responsible for the wider OA compared to wolf skulls are mainly the lateralisation of the zygomatic process of the frontal bone. Our conclusion is that the orbital angle can be used as an additional morphological measuring method to discern wolves from recent and archaeological dogs. Angles above 60° are certainly from recent dogs. Angles

  11. Can a surgeon drill accurately at a specified angle?

    PubMed Central

    Brioschi, Valentina; Cook, Jodie; Arthurs, Gareth I

    2016-01-01

    Objectives To investigate whether a surgeon can drill accurately a specified angle and whether surgeon experience, task repetition, drill bit size and perceived difficulty influence drilling angle accuracy. Methods The sample population consisted of final-year students (n=25), non-specialist veterinarians (n=22) and board-certified orthopaedic surgeons (n=8). Each participant drilled a hole twice in a horizontal oak plank at 30°, 45°, 60°, 80°, 85° and 90° angles with either a 2.5  or a 3.5 mm drill bit. Participants then rated the perceived difficulty to drill each angle. The true angle of each hole was measured using a digital goniometer. Results Greater drilling accuracy was achieved at angles closer to 90°. An error of ≤±4° was achieved by 84.5 per cent of participants drilling a 90° angle compared with approximately 20 per cent of participants drilling a 30–45° angle. There was no effect of surgeon experience, task repetition or drill bit size on the mean error for intended versus achieved angle. Increased perception of difficulty was associated with the more acute angles and decreased accuracy, but not experience level. Clinical significance This study shows that surgeon ability to drill accurately (within ±4° error) is limited, particularly at angles ≤60°. In situations where drill angle is critical, use of computer-assisted navigation or custom-made drill guides may be preferable. PMID:27547423

  12. Angle closure glaucoma in congenital ectropion uvea.

    PubMed

    Wang, Grace M; Thuente, Daniel; Bohnsack, Brenda L

    2018-06-01

    Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months) and required additional surgery (cycloablation or trabeculectomy). Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control.

  13. The Effect of Suture Anchor Insertion Angle on Calcaneus Pullout Strength: Challenging the Deadman's Angle.

    PubMed

    Weiss, William M; Saucedo, Ramon P; Robinson, John D; Lo, Chung-Chieh Jason; Morris, Randal P; Panchbhavi, Vinod K

    2017-10-01

    Refractory cases of Achilles tendinopathy amenable to surgery may include reattachment of the tendon using suture anchors. However, there is paucity of information describing the optimal insertion angle to maximize the tendon footprint and anchor stability in the calcaneus. The purpose of this investigation is to compare the fixation strength of suture anchors inserted at 90° and 45° (the Deadman's angle) relative to the primary compressive trabeculae of the calcaneus. A total of 12 matched pairs of adult cadaveric calcanei were excised and potted to approximate their alignment in vivo. Each pair was implanted with 5.5-mm bioabsorbable suture anchors placed either perpendicular (90°) or oblique (45°) to the primary compressive trabeculae. A tensile load was applied until failure of anchor fixation. Differences in failure load and stiffness between anchor fixation angles were determined by paired t-tests. No significant differences were detected between perpendicular and oblique suture anchor insertion relative to primary compressive trabeculae in terms of load to failure or stiffness. This investigation suggests that the fixation strength of suture anchors inserted perpendicular to the primary compression trabeculae and at the Deadman's angle are possibly comparable. Biomechanical comparison study.

  14. Computer programs for calculation of sting pitch and roll angles required to obtain angles of attack and sideslip on wind tunnel models

    NASA Technical Reports Server (NTRS)

    Peterson, John B., Jr.

    1988-01-01

    Two programs have been developed to calculate the pitch and roll angles of a wind-tunnel sting drive system that will position a model at the desired angle of attack and and angle of sideslip in the wind tunnel. These programs account for the effects of sting offset angles, sting bending angles and wind-tunnel stream flow angles. In addition, the second program incorporates inputs from on-board accelerometers that measure model pitch and roll with respect to gravity. The programs are presented in the report and a description of the numerical operation of the programs with a definition of the variables used in the programs is given.

  15. RaptorX-Angle: real-value prediction of protein backbone dihedral angles through a hybrid method of clustering and deep learning.

    PubMed

    Gao, Yujuan; Wang, Sheng; Deng, Minghua; Xu, Jinbo

    2018-05-08

    Protein dihedral angles provide a detailed description of protein local conformation. Predicted dihedral angles can be used to narrow down the conformational space of the whole polypeptide chain significantly, thus aiding protein tertiary structure prediction. However, direct angle prediction from sequence alone is challenging. In this article, we present a novel method (named RaptorX-Angle) to predict real-valued angles by combining clustering and deep learning. Tested on a subset of PDB25 and the targets in the latest two Critical Assessment of protein Structure Prediction (CASP), our method outperforms the existing state-of-art method SPIDER2 in terms of Pearson Correlation Coefficient (PCC) and Mean Absolute Error (MAE). Our result also shows approximately linear relationship between the real prediction errors and our estimated bounds. That is, the real prediction error can be well approximated by our estimated bounds. Our study provides an alternative and more accurate prediction of dihedral angles, which may facilitate protein structure prediction and functional study.

  16. Biomechanical comparison of two surgical techniques for press-fit reconstruction of the posterolateral complex of the knee.

    PubMed

    Panzica, Martin; Janzik, Janne; Bobrowitsch, Evgenij; Krettek, Christian; Hawi, Nael; Hurschler, Christof; Jagodzinski, Michael

    2015-11-01

    -posterior translation at any flexion angles (p > 0.05). Comparing both reconstruction techniques, significant higher varus-/valgus stability was registered for the fibula-based Larson technique at 90° knee flexion (p < 0.05). Both PLC reconstructions showed equal biomechanical stability as the intact posterolateral knee structures when using knot-bone cylinder press-fit fixation. We registered restoration of the rotational and varus-valgus stability with both surgical techniques. The anterior-posterior translational stability was not influenced significantly. The Larson technique showed significant higher varus/valgus stability in 90° flexion. The latter is easier to perform and takes half the preparation time, but needs grafting of the semitendinosus tendon. The Kawano reconstruction technique is an interesting alternative in cases of missing autografts.

  17. Ulnohumeral chondral and ligamentous overload: biomechanical correlation for posteromedial chondromalacia of the elbow in throwing athletes.

    PubMed

    Osbahr, Daryl C; Dines, Joshua S; Breazeale, Nathan M; Deng, Xiang-Hua; Altchek, David W

    2010-12-01

    Previous studies have documented increased posteromedial contact forces with the elbow at lower flexion angles associated with valgus extension overload; however, the authors believe that posteromedial elbow impingement in association with valgus laxity is a complex pathological process that may occur throughout the entire throwing motion in the form of ulnohumeral chondral and ligamentous overload. Valgus laxity with the elbow at 90° of flexion may lead to chondromalacia secondary to a subtle shift in the contact point between the tip of the olecranon and the distal humeral trochlea. Controlled laboratory study. Six fresh human cadaveric elbows were dissected and subjected to a static valgus load. Pressure-sensitive Fuji film measured the contact pressure, contact area, and shift in contact area across the posteromedial elbow before and after sectioning the anterior bundle of the ulnar collateral ligament. The contact pressure between the tip of the olecranon process and the medial crista of the posterior humeral trochlea significantly increased, from an average of 0.27 ± 0.06 kg/cm² to 0.40 ± 0.08 kg/cm². The contact area also significantly decreased, from an average of 30.34 ± 9.17 mm² to 24.59 ± 6.44 mm², and shifted medially on the medial humeral crista, which corresponds to the position of the posteromedial chondral lesions that was observed in throwing athletes in the authors' clinical practice. While simulating the early acceleration phase of the throwing motion with the elbow in 90° of flexion, the results illustrate that abnormal contact may occur as a result of valgus laxity through increased contact pressures across the posteromedial elbow between the medial tip of the olecranon and medial crista of the humeral trochlea. In addition, congruency of the ulnohumeral joint changed, as there was a statistically significant medial shift of the olecranon on the posterior humeral trochlea with the elbow at 90° of flexion after sectioning the anterior

  18. Wide-angle vision for road views

    NASA Astrophysics Data System (ADS)

    Huang, F.; Fehrs, K.-K.; Hartmann, G.; Klette, R.

    2013-03-01

    The field-of-view of a wide-angle image is greater than (say) 90 degrees, and so contains more information than available in a standard image. A wide field-of-view is more advantageous than standard input for understanding the geometry of 3D scenes, and for estimating the poses of panoramic sensors within such scenes. Thus, wide-angle imaging sensors and methodologies are commonly used in various road-safety, street surveillance, street virtual touring, or street 3D modelling applications. The paper reviews related wide-angle vision technologies by focusing on mathematical issues rather than on hardware.

  19. Biomarkers in primary open angle glaucoma.

    PubMed

    Kokotas, Haris; Kroupis, Christos; Chiras, Dimitrios; Grigoriadou, Maria; Lamnissou, Klea; Petersen, Michael B; Kitsos, George

    2012-12-01

    Glaucoma, a leading cause of blindness worldwide, is currently defined as a disturbance of the structural or functional integrity of the optic nerve that causes characteristic atrophic changes in the optic nerve, which may lead to specific visual field defects over time. This disturbance usually can be arrested or diminished by adequate lowering of intraocular pressure (IOP). Glaucoma can be divided roughly into two main categories, ‘ open angle ’ and ‘ closed angle ’ glaucoma.Open angle, chronic glaucoma tends to progress at a slower rate and patients may not notice loss of vision until the disease has progressed significantly. Primary open angle glaucoma(POAG) is described distinctly as a multifactorial optic neuropathy that is chronic and progressive with a characteristic acquired loss of optic nerve fibers. Such loss develops in the presence of open anterior chamber angles, characteristic visual field abnormalities, and IOP that is too high for the healthy eye. It manifests by cupping and atrophy of the optic disc, in the absence of other known causes of glaucomatous disease. Several biological markers have been implicated with the disease. The purpose of this study was to summarize the current knowledge regarding the non-genetic molecular markers which have been predicted to have an association with POAG but have not yet been validated.

  20. Apparatus and method for variable angle slant hole collimator

    DOEpatents

    Lee, Seung Joon; Kross, Brian J.; McKisson, John E.

    2017-07-18

    A variable angle slant hole (VASH) collimator for providing collimation of high energy photons such as gamma rays during radiological imaging of humans. The VASH collimator includes a stack of multiple collimator leaves and a means of quickly aligning each leaf to provide various projection angles. Rather than rotate the detector around the subject, the VASH collimator enables the detector to remain stationary while the projection angle of the collimator is varied for tomographic acquisition. High collimator efficiency is achieved by maintaining the leaves in accurate alignment through the various projection angles. Individual leaves include unique angled cuts to maintain a precise target collimation angle. Matching wedge blocks driven by two actuators with twin-lead screws accurately position each leaf in the stack resulting in the precise target collimation angle. A computer interface with the actuators enables precise control of the projection angle of the collimator.

  1. In situ assessment of the contact angles of nanoparticles adsorbed at fluid interfaces by multiple angle of incidence ellipsometry.

    PubMed

    Stocco, Antonio; Su, Ge; Nobili, Maurizio; In, Martin; Wang, Dayang

    2014-09-28

    Here multiple angle of incidence ellipsometry was successfully applied to in situ assess the contact angle and surface coverage of gold nanoparticles as small as 18 nm, coated with stimuli-responsive polymers, at water-oil and water-air interfaces in the presence of NaCl and NaOH, respectively. The interfacial adsorption of the nanoparticles was found to be very slow and took days to reach a fairly low surface coverage. For water-oil interfaces, in situ nanoparticle contact angles agree with the macroscopic equilibrium contact angles of planar gold surfaces with the same polymer coatings, whilst for water-air interfaces, significant differences have been observed.

  2. Trabecular Meshwork Height in Primary Open-Angle Glaucoma Versus Primary Angle-Closure Glaucoma.

    PubMed

    Masis, Marisse; Chen, Rebecca; Porco, Travis; Lin, Shan C

    2017-11-01

    To determine if trabecular meshwork (TM) height differs between primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) eyes. Prospective, cross-sectional clinical study. Adult patients were consecutively recruited from glaucoma clinics at the University of California, San Francisco, from January 2012 to July 2015. Images were obtained from spectral-domain optical coherence tomography (Cirrus OCT; Carl Zeiss Meditec, Inc, Dublin, California, USA). Univariate and multivariate linear mixed models comparing TM height and glaucoma type were performed to assess the relationship between TM height and glaucoma subtype. Mixed-effects regression was used to adjust for the use of both eyes in some subjects. The study included 260 eyes from 161 subjects, composed of 61 men and 100 women. Mean age was 70 years (SD 11.77). There were 199 eyes (123 patients) in the POAG group and 61 eyes (38 patients) in the PACG group. Mean TM heights in the POAG and PACG groups were 812 ± 13 μm and 732 ± 27 μm, respectively, and the difference was significant in univariate analysis (P = .004) and in multivariate analysis (β = -88.7 [24.05-153.5]; P = .008). In this clinic-based population, trabecular meshwork height is shorter in PACG patients compared to POAG patients. This finding may provide insight into the pathophysiology of angle closure and provide assistance in future diagnosis, prevention, and management of the angle-closure spectrum of disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. NORAD LOOK ANGLES AND PIO SATELLITE PACKAGE

    NASA Technical Reports Server (NTRS)

    ANONYMOUS

    1994-01-01

    This program package consists of two programs. First is the NORAD Look Angles Program, which computes satellite look angles (azimuth, elevation, and range) as well as the subsatellite points (latitude, longitude, and height). The second program in this package is the PIO Satellite Program, which computes sighting directions, visibility times, and the maximum elevation angle attained during each pass of an earth-orbiting satellite. Computations take into consideration the observing location and the effect of the earth's shadow on the satellite visibility. Input consists of a magnetic tape prepared by the NORAD Look Angles Program and punched cards containing reference Julian date, right ascension, declination, mean sidereal time at zero hours universal time of the reference date, and daily changes of these quantities. Output consists of a tabulated listing of the satellite's rise and set times, direction, and the maximum elevation angle visible from each observing location. This program has been implemented on the GE 635. The program Assembler code can easily be replaced by FORTRAN statements.

  4. Deep learning methods for protein torsion angle prediction.

    PubMed

    Li, Haiou; Hou, Jie; Adhikari, Badri; Lyu, Qiang; Cheng, Jianlin

    2017-09-18

    Deep learning is one of the most powerful machine learning methods that has achieved the state-of-the-art performance in many domains. Since deep learning was introduced to the field of bioinformatics in 2012, it has achieved success in a number of areas such as protein residue-residue contact prediction, secondary structure prediction, and fold recognition. In this work, we developed deep learning methods to improve the prediction of torsion (dihedral) angles of proteins. We design four different deep learning architectures to predict protein torsion angles. The architectures including deep neural network (DNN) and deep restricted Boltzmann machine (DRBN), deep recurrent neural network (DRNN) and deep recurrent restricted Boltzmann machine (DReRBM) since the protein torsion angle prediction is a sequence related problem. In addition to existing protein features, two new features (predicted residue contact number and the error distribution of torsion angles extracted from sequence fragments) are used as input to each of the four deep learning architectures to predict phi and psi angles of protein backbone. The mean absolute error (MAE) of phi and psi angles predicted by DRNN, DReRBM, DRBM and DNN is about 20-21° and 29-30° on an independent dataset. The MAE of phi angle is comparable to the existing methods, but the MAE of psi angle is 29°, 2° lower than the existing methods. On the latest CASP12 targets, our methods also achieved the performance better than or comparable to a state-of-the art method. Our experiment demonstrates that deep learning is a valuable method for predicting protein torsion angles. The deep recurrent network architecture performs slightly better than deep feed-forward architecture, and the predicted residue contact number and the error distribution of torsion angles extracted from sequence fragments are useful features for improving prediction accuracy.

  5. Metric analysis of basal sphenoid angle in adult human skulls

    PubMed Central

    Netto, Dante Simionato; Nascimento, Sergio Ricardo Rios; Ruiz, Cristiane Regina

    2014-01-01

    Objective To analyze the variations in the angle basal sphenoid skulls of adult humans and their relationship to sex, age, ethnicity and cranial index. Methods The angles were measured in 160 skulls belonging to the Museum of the Universidade Federal de São Paulo Department of Morphology. We use two flexible rules and a goniometer, having as reference points for the first rule the posterior end of the ethmoidal crest and dorsum of the sella turcica, and for the second rule the anterior margin of the foramen magnum and clivus, measuring the angle at the intersection of two. Results The average angle was 115.41°, with no statistical correlation between the value of the angle and sex or age. A statistical correlation was noted between the value of the angle and ethnicity, and between the angle and the horizontal cranial index. Conclusions The distribution of the angle basal sphenoid was the same in sex, and there was correlation between the angle and ethnicity, being the proportion of non-white individuals with an angle >125° significantly higher than that of whites with an angle >125°. There was correlation between the angle and the cranial index, because skulls with higher cranial index tend to have higher basiesfenoidal angle too. PMID:25295452

  6. Limbus Impact on Off-angle Iris Degradation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karakaya, Mahmut; Barstow, Del R; Santos-Villalobos, Hector J

    The accuracy of iris recognition depends on the quality of data capture and is negatively affected by several factors such as angle, occlusion, and dilation. Off-angle iris recognition is a new research focus in biometrics that tries to address several issues including corneal refraction, complex 3D iris texture, and blur. In this paper, we present an additional significant challenge that degrades the performance of the off-angle iris recognition systems, called the limbus effect . The limbus is the region at the border of the cornea where the cornea joins the sclera. The limbus is a semitransparent tissue that occludes amore » side portion of the iris plane. The amount of occluded iris texture on the side nearest the camera increases as the image acquisition angle increases. Without considering the role of the limbus effect, it is difficult to design an accurate off-angle iris recognition system. To the best of our knowledge, this is the first work that investigates the limbus effect in detail from a biometrics perspective. Based on results from real images and simulated experiments with real iris texture, the limbus effect increases the hamming distance score between frontal and off-angle iris images ranging from 0.05 to 0.2 depending upon the limbus height.« less

  7. Non-surgical treatment of hallux valgus: a current practice survey of Australian podiatrists.

    PubMed

    Hurn, Sheree E; Vicenzino, Bill T; Smith, Michelle D

    2016-01-01

    Patients with hallux valgus (HV) frequently present to podiatrists for non-surgical management, with a wide range of concerns including pain, footwear difficulty and quality of life impacts. There is little research evidence guiding podiatrists' clinical decisions surrounding non-surgical management of HV. Thus practitioners rely largely upon clinical experience and expert opinion. This survey was conducted to determine whether a consensus exists among Australian podiatrists regarding non-surgical treatment of HV, and secondly to explore common presenting concerns and physical examination findings associated with HV. An online survey was distributed to Australian podiatrists in mid-2013 via the professional association in each state (approximately 1900 members). Podiatrists indicated common treatments recommended, presenting problems and physical examination findings associated with HV in juveniles, adults and older adults. Proportions were calculated to determine the most common responses, and Chi-squared tests were used to examine differences in treatment recommendations according to HV patient age group and podiatrist demographics. Of 210 survey respondents, 65 % (136) were female and 80 % (168) were private practitioners. Complete survey responses were received from 159 podiatrists for juvenile HV, 146 for adults and 141 for older adults. Seven different non-surgical treatment options were commonly recommended (by >50 % podiatrists), although recommendations differed between adult, older adult and juvenile HV. Common treatments included footwear advice or modification, custom and prefabricated orthotic devices, addition of padding, and muscle strengthening/retraining exercises. Padding was more likely to be utilised in older adults, while exercises were more likely to be prescribed for juveniles. A diverse range of presenting problems and physical examination findings were reported to be associated with HV. Despite the lack of empirical evidence in this area

  8. Thumb rule of visual angle: a new confirmation.

    PubMed

    Groot, C; Ortega, F; Beltran, F S

    1994-02-01

    The classical thumb rule of visual angle was reexamined. Hence, the visual angle was measured as a function of a thumb's width and the distance between eye and thumb. The measurement of a thumb's width when held at arm's length was taken on 67 second-year students of psychology. The visual angle was about 2 degrees as R. P. O'Shea confirmed in 1991. Also, we confirmed a linear relationship between the size of a thumb's width at arm's length and the visual angle.

  9. Iridotomy to slow progression of angle-closure glaucoma

    PubMed Central

    Le, Jimmy T; Rouse, Benjamin; Gazzard, Gus

    2016-01-01

    This is the protocol for a review and there is no abstract. The objectives are as follows: The primary objective is to assess the role of iridotomy-compared with observation-in the prevention of visual field loss for individuals who have primary angle closure or primary angle-closure glaucoma in at least one eye. We will also examine the role of iridotomy in the prevention of elevated intraocular pressure (IOP) in individuals with narrow angles (primary angle-closure suspect) in at least one eye. PMID:27551238

  10. Ducted turbine theory with right angled ducts

    NASA Astrophysics Data System (ADS)

    McLaren-Gow, S.; Jamieson, P.; Graham, J. M. R.

    2014-06-01

    This paper describes the use of an inviscid approach to model a ducted turbine - also known as a diffuser augmented turbine - and a comparison of results with a particular one-dimensional theory. The aim of the investigation was to gain a better understanding of the relationship between a real duct and the ideal diffuser, which is a concept that is developed in the theory. A range of right angled ducts, which have a rim for a 90° exit angle, were modelled. As a result, the performance of right angled ducts has been characterised in inviscid flow. It was concluded that right angled ducts cannot match the performance of their associated ideal diffuser and that the optimum rotor loading for these turbines varies with the duct dimensions.

  11. Complications and Reoperations in Mandibular Angle Fractures.

    PubMed

    Chen, Collin L; Zenga, Joseph; Patel, Ruchin; Branham, Gregory

    2018-05-01

    Mandible angle fractures can be repaired in a variety of ways, with no consensus on the outcomes of complications and reoperation rates. To analyze patient, injury, and surgical factors, including approach to the angle and plating technique, associated with postoperative complications, as well as the rate of reoperation with regard to mandible angle fractures. Retrospective cohort study analyzing the surgical outcomes of patients with mandible angle fractures between January 1, 2000, and December 31, 2015, who underwent open reduction and internal fixation. Patients were eligible if they were aged 18 years or older, had 3 or less mandible fractures with 1 involving the mandibular angle, and had adequate follow-up data. Patients with comminuted angle fractures, bilateral angle fractures, and multiple surgical approaches were excluded. A total of 135 patients were included in the study. All procedures were conducted at a single, large academic hospital located in an urban setting. Major complications and reoperation rates. Major complications included in this study were nonunion, malunion, severe malocclusion, severe infection, and exposed hardware. Of 135 patients 113 (83.7%) were men; median age was 29 years (range, 18-82 years). Eighty-seven patients (64.4%) underwent the transcervical approach and 48 patients (35.6%) received the transoral approach. Fifteen (17.2%) patients in the transcervical group and 9 (18.8%) patients in the transoral group experienced major complications (difference, 1%; 95% CI, -8% to 10%). Thirteen (14.9%) patients in the transcervical group and 8 (16.7%) patients in the transoral group underwent reoperations (difference, 2%; 95% CI, -13% to 17%). Active smoking had a significant effect on the rate of major complications (odds ratio, 4.04; 95% CI, 1.07 to 15.34; P = .04). During repair of noncomminuted mandibular angle fractures, both of the commonly used approaches-transcervical and transoral-can be used during treatment with equal

  12. The SU(2) action-angle variables

    NASA Technical Reports Server (NTRS)

    Ellinas, Demosthenes

    1993-01-01

    Operator angle-action variables are studied in the frame of the SU(2) algebra, and their eigenstates and coherent states are discussed. The quantum mechanical addition of action-angle variables is shown to lead to a noncommutative Hopf algebra. The group contraction is used to make the connection with the harmonic oscillator.

  13. Design of an all-attitude flight control system to execute commanded bank angles and angles of attack

    NASA Technical Reports Server (NTRS)

    Burgin, G. H.; Eggleston, D. M.

    1976-01-01

    A flight control system for use in air-to-air combat simulation was designed. The input to the flight control system are commanded bank angle and angle of attack, the output are commands to the control surface actuators such that the commanded values will be achieved in near minimum time and sideslip is controlled to remain small. For the longitudinal direction, a conventional linear control system with gains scheduled as a function of dynamic pressure is employed. For the lateral direction, a novel control system, consisting of a linear portion for small bank angle errors and a bang-bang control system for large errors and error rates is employed.

  14. Opening-wedge high tibial osteotomy with a locked low-profile plate: surgical technique.

    PubMed

    Kolb, Werner; Guhlmann, Hanno; Windisch, Christoph; Koller, Heiko; Grützner, Paul; Kolb, Klaus

    2010-09-01

    High tibial osteotomy has been recognized as a beneficial treatment for osteoarthritis of the medial compartment of the knee. The purpose of this prospective study was to assess the short-term results of opening-wedge high tibial osteotomies with locked plate fixation. From September 2002 to November 2005, fifty-one consecutive medial opening-wedge high tibial osteotomies were performed. The mean age of the patients at the time of the index operation was forty-nine years. The preoperative and postoperative factors analyzed included the grade of arthritis of the tibiofemoral compartment (the Ahlbäck radiographic grade), the anatomic tibiofemoral angle, patellar height, the Hospital for Special Surgery rating system score, and the Lysholm and Gillquist knee score. Postoperatively, one superficial wound infection occurred. Fifty of the fifty-one osteotomies healed after an average period of 12.9 weeks (range, eight to sixteen weeks) without bone grafts. A nonunion developed in a sixty-two-year-old patient who was a cigarette smoker. The average postoperative tibiofemoral angle was 9° of valgus. Forty-nine patients were followed for a mean of fifty-two months. The average score on the Hospital for Special Surgery rating system was 86 points at the time of the most recent follow-up. The rating was excellent in twenty-eight patients (57%), good in twelve (24%), fair in four (8%), and poor in five (10%). The average score on the Lysholm and Gillquist knee-scoring scale was 83 points. According to these scores, the outcome was excellent in nine patients (18%), good in thirty-one (63%), fair in three (6%), and poor in six (12%). Four knees failed after an average of thirty-six months. Our results suggest that an opening-wedge high tibial osteotomy with locked plate fixation allows a correct valgus angle to be achieved with good short-term results.

  15. Range of variation of genu valgum and association with anthropometric characteristics and physical activity: comparison between children aged 3-9 years.

    PubMed

    Kaspiris, Angelos; Zaphiropoulou, Chrisi; Vasiliadis, Elias

    2013-07-01

    The lower limbs of children aged 3-9 years present varying knock-knee deformities that have a direct impact on the diversification of the load-bearing axis of the valgus limb and on the modification of gait kinematics. The purpose of our study was to establish the reference values of knee alignment in a Greek population and whether this is linked to a change in the physical activity of children depending on the severity of the genu valgum. Using a clinical method, we measured both the tibiofemoral (TF) angle and the intermalleolar (IM) distance of the lower extremities of normal children. Subsequently, forms of the Netherlands Physical Activity Questionnaire (NPAQ) for young children and the Baecke questionnaire on habitual physical activity, modified especially for children, were completed by the parents. We examined both the development of the TF angle and the IM distance in relation to age and the degree of restriction of physical activity in relation to the severity of the genu valgum. We analysed 316 unaffected lower extremities in children aged 3-9 years. The average value of the TF angle starts around 7° at the age of 3 years and gradually decreases to 4° at the age of 7-8 years. The average value of the IM distance ranges over 3.5 cm at the age of 3 years and progressively decreases to 2 cm at the age of 7-8 years. Physical activity appears to be influenced by sex and the severity of the genu valgum. We provide age-specific values for limb alignment and joint orientation of the lower extremity in children aged 3-9 years. A statistical correlation between all indexes (sport, leisure time and total) of the Baecke and the NPAQs and measurements of genu valgum was noted depending on the severity of the valgus deformity.

  16. Wide Angle Movie

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This brief movie illustrates the passage of the Moon through the Saturn-bound Cassini spacecraft's wide-angle camera field of view as the spacecraft passed by the Moon on the way to its closest approach with Earth on August 17, 1999. From beginning to end of the sequence, 25 wide-angle images (with a spatial image scale of about 14 miles per pixel (about 23 kilometers)were taken over the course of 7 and 1/2 minutes through a series of narrow and broadband spectral filters and polarizers, ranging from the violet to the near-infrared regions of the spectrum, to calibrate the spectral response of the wide-angle camera. The exposure times range from 5 milliseconds to 1.5 seconds. Two of the exposures were smeared and have been discarded and replaced with nearby images to make a smooth movie sequence. All images were scaled so that the brightness of Crisium basin, the dark circular region in the upper right, is approximately the same in every image. The imaging data were processed and released by the Cassini Imaging Central Laboratory for Operations (CICLOPS)at the University of Arizona's Lunar and Planetary Laboratory, Tucson, AZ.

    Photo Credit: NASA/JPL/Cassini Imaging Team/University of Arizona

    Cassini, launched in 1997, is a joint mission of NASA, the European Space Agency and Italian Space Agency. The mission is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

  17. Incident angle of saltating particles in wind-blown sand.

    PubMed

    Fu, Lin-Tao; Bo, Tian-Li; Gu, Hai-Hua; Zheng, Xiao-Jing

    2013-01-01

    Incident angle of saltating particles plays a very important role in aeolian events. In this paper, the incident angles of sand particles near the sand bed were measured in wind tunnel. It reveals that the incident angles range widely from 0° to 180° and thereby the means of angles are larger than published data. Surprisingly, it is found the proportion that angles of 5°-15° occupy is far below previous reports. The measuring height is probably the most important reason for the measurement differences between this study and previous investigations.

  18. Bounded-Angle Iterative Decoding of LDPC Codes

    NASA Technical Reports Server (NTRS)

    Dolinar, Samuel; Andrews, Kenneth; Pollara, Fabrizio; Divsalar, Dariush

    2009-01-01

    Bounded-angle iterative decoding is a modified version of conventional iterative decoding, conceived as a means of reducing undetected-error rates for short low-density parity-check (LDPC) codes. For a given code, bounded-angle iterative decoding can be implemented by means of a simple modification of the decoder algorithm, without redesigning the code. Bounded-angle iterative decoding is based on a representation of received words and code words as vectors in an n-dimensional Euclidean space (where n is an integer).

  19. Effectiveness of Variable-Gain Kalman Filter Based on Angle Error Calculated from Acceleration Signals in Lower Limb Angle Measurement with Inertial Sensors

    PubMed Central

    Watanabe, Takashi

    2013-01-01

    The wearable sensor system developed by our group, which measured lower limb angles using Kalman-filtering-based method, was suggested to be useful in evaluation of gait function for rehabilitation support. However, it was expected to reduce variations of measurement errors. In this paper, a variable-Kalman-gain method based on angle error that was calculated from acceleration signals was proposed to improve measurement accuracy. The proposed method was tested comparing to fixed-gain Kalman filter and a variable-Kalman-gain method that was based on acceleration magnitude used in previous studies. First, in angle measurement in treadmill walking, the proposed method measured lower limb angles with the highest measurement accuracy and improved significantly foot inclination angle measurement, while it improved slightly shank and thigh inclination angles. The variable-gain method based on acceleration magnitude was not effective for our Kalman filter system. Then, in angle measurement of a rigid body model, it was shown that the proposed method had measurement accuracy similar to or higher than results seen in other studies that used markers of camera-based motion measurement system fixing on a rigid plate together with a sensor or on the sensor directly. The proposed method was found to be effective in angle measurement with inertial sensors. PMID:24282442

  20. How Wedge You Teach the Unit-Angle Concept?

    ERIC Educational Resources Information Center

    Millsaps, Gayle M.

    2012-01-01

    The concepts of angle and angle measure have been acknowledged as difficult for elementary school students to grasp (Strutchens, Martin, and Kenney 2003). The Wedge activity (Browning and Garza-Kling 2009; Van de Walle 2004; Wilson 1990) can provide an opportunity for students to examine their understanding of angle measurement and to rethink what…

  1. SPECTROSCOPIC AND PHOTOMETRIC VARIABILITY IN THE A0 SUPERGIANT HR 1040

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Corliss, David J.; Morrison, Nancy D.; Adelman, Saul J., E-mail: david.corliss@wayne.edu

    2015-12-15

    A time-series analysis of spectroscopic and photometric observables of the A0 Ia supergiant HR 1040 has been performed, including equivalent widths, radial velocities, and Strömgren photometric indices. The data, obtained from 1993 through 2007, include 152 spectroscopic observations from the Ritter Observatory 1 m telescope and 269 Strömgren photometric observations from the Four College Automated Photoelectric Telescope. Typical of late B- and early A-type supergiants, HR 1040 has a highly variable Hα profile. The star was found to have an intermittent active phase marked by correlation between the Hα absorption equivalent width and blue-edge radial velocity and by photospheric connectionsmore » observed in correlations to equivalent width, second moment and radial velocity in Si ii λλ6347, 6371. High-velocity absorption (HVA) events were observed only during this active phase. HVA events in the wind were preceded by photospheric activity, including Si ii radial velocity oscillations 19–42 days prior to onset of an HVA event and correlated increases in Si ii W{sub λ} and second moment from 13 to 23 days before the start of the HVA event. While increases in various line equivalent widths in the wind prior to HVA events have been reported in the past in other stars, our finding of precursors in enhanced radial velocity variations in the wind and at the photosphere is a new result.« less

  2. Effects of aripiprazole and the Taq1A polymorphism in the dopamine D2 receptor gene on the clinical response and plasma monoamine metabolites level during the acute phase of schizophrenia.

    PubMed

    Miura, Itaru; Takeuchi, Satoshi; Katsumi, Akihiko; Mori, Azuma; Kanno, Keiko; Yang, Qiaohui; Mashiko, Hirobumi; Numata, Yoshihiko; Niwa, Shin-Ichi

    2012-02-01

    The Taq1A polymorphism in the dopamine D2 receptor (DRD2) gene could be related to the response to antipsychotics. We examined the effects of the Taq1A polymorphism on the plasma monoamine metabolites during the treatment of schizophrenia with aripiprazole, a DRD2 partial agonist. Thirty Japanese patients with schizophrenia were treated with aripiprazole for 6 weeks. We measured plasma levels of homovanillic acid (pHVA) and 3-methoxy-4hydroxyphenylglycol (pMHPG) before and after treatment. The Taq1A polymorphism was genotyped with polymerase chain reaction. Aripiprazole improved the acute symptoms of schizophrenia and decreased pHVA in responders (P = 0.023) but not in nonresponders (P = 0.28). Although A1 allele carriers showed a tendency to respond to aripiprazole (61.5%) compared to A1 allele noncarriers (29.4%) (P = 0.078), there was not statistically significant difference in the response between the 2 genotype groups. There were significant effect for response (P = 0.013) and genotype × response interaction (P = 0.043) on the change of pHVA. The changes of pHVA differ between responders and nonresponders in A1 allele carriers but not in A1 allele noncarriers. There were no genotype or response effects or genotype × response interaction on the changes of the plasma levels of 3-methoxy-4hydroxyphenylglycol. Our preliminary results suggest that Taq1A polymorphism may be partly associated with changes in pHVA during acute schizophrenia.

  3. A Universal Formula for Extracting the Euler Angles

    NASA Technical Reports Server (NTRS)

    Shuster, Malcolm D.; Markley, F. Landis

    2004-01-01

    Recently, the authors completed a study of the Davenport angles, which are a generalization of the Euler angles for which the initial and final Euler axes need not be either mutually parallel or mutually perpendicular or even along the coordinate axes. During the conduct of that study, those authors discovered a relationship which can be used to compute straightforwardly the Euler angles characterizing a proper-orthogonal direction-cosine matrix for an arbitrary Euler-axis set satisfying n(sub 1) x n(sub 2) = 0 and n(sub 3) x n(sub 1) = 0, which is also satisfied by the more usual Euler angles we encounter commonly in the practice of Astronautics. Rather than leave that relationship hidden in an article with very different focus from the present Engineering note, we present it and the universal algorithm derived from it for extracting the Euler angles from the direction-cosine matrix here. We also offer literal "code" for performing the operations, numerical examples, and general considerations about the extraction of Euler angles which are not universally known, particularly, the treatment of statistical error.

  4. Integrating health economics into the product development cycle: a case study of absorbable pins for treating hallux valgus.

    PubMed

    Vallejo-Torres, Laura; Steuten, Lotte; Parkinson, Bonny; Girling, Alan J; Buxton, Martin J

    2011-01-01

    The probability of reimbursement is a key factor in determining whether to proceed with or abandon a product during its development. The purpose of this article is to illustrate how the methods of iterative Bayesian economic evaluation proposed in the literature can be incorporated into the development process of new medical devices, adapting them to face the relative scarcity of data and time that characterizes the process. A 3-stage economic evaluation was applied: an early phase in which simple methods allow for a quick prioritization of competing products; a mid-stage in which developers synthesize the data into a decision model, identify the parameters for which more information is most valuable, and explore uncertainty; and a late stage, in which all relevant information is synthesized. A retrospective analysis was conducted of the case study of absorbable pins, compared with metallic fixation, in osteotomy to treat hallux valgus. The results from the early analysis suggest absorbable pins to be cost-effective under the beliefs and assumptions applied. The outputs from the models at the mid-stage analyses show the device to be cost-effective with a high probability. Late-stage analysis synthesizes evidence from a randomized controlled trial and informative priors, which are based on previous evidence. It also suggests that absorbable pins are the most cost-effective strategy, although the uncertainty in the model output increased considerably. This example illustrates how the method proposed allows decisions in the product development cycle to be based on the best knowledge that is available at each stage.

  5. The effect of videotape augmented feedback on drop jump landing strategy: Implications for anterior cruciate ligament and patellofemoral joint injury prevention.

    PubMed

    Munro, Allan; Herrington, Lee

    2014-10-01

    Modification of high-risk movement strategies such as dynamic knee valgus is key to the reduction of anterior cruciate ligament (ACL) and patellofemoral joint (PFJ) injuries. Augmented feedback, which includes video and verbal feedback, could offer a quick, simple and effective alternative to training programs for altering high-risk movement patterns. It is not clear whether feedback can reduce dynamic knee valgus measured using frontal plane projection angle (FPPA). Vertical ground reaction force (vGRF), two-dimensional FPPA of the knee, contact time and jump height of 20 recreationally active university students were measured during a drop jump task pre- and post- an augmented feedback intervention. A control group of eight recreationally active university students were also studied at baseline and repeat test. There was a significant reduction in vGRF (p=0.033), FPPA (p<0.001) and jump height (p<0.001) and an increase in contact time (p<0.001) post feedback in the intervention group. No changes were evident in the control group. Augmented feedback leads to significant decreases in vGRF, FPPA and contact time which may help to reduce ACL and PFJ injury risk. However, these changes may result in decreased performance. Augmented feedback reduces dynamic knee valgus, as measured via FPPA, and forces experienced during the drop jump task and therefore could be used as a tool for helping decrease ACL and PFJ injury risk prior to, or as part of, the implementation of injury prevention training programs. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Exclusive Backward-Angle Omega Meson Electroproduction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wenliang, Li

    Exclusive meson electroproduction at different squared four-momenta of the exchanged virtual photon, Q 2 , and at different four-momentum transfers, t and u, can be used to probe QCD's transition from hadronic degrees of freedom at the long distance scale to quark-gluon degrees of freedom at the short distance scale. Backward-angle meson electroproduction was previously ignored, but is anticipated to offer complimentary information to conventional forward-angle meson electroproduction studies on nucleon structure. This work is a pioneering study of backward-angle ω cross sections through the exclusive 1H(e, e'p)ω reaction using the missing mass reconstruction technique. The extracted cross sections aremore » separated into the transverse (T), longitudinal (L), and LT, TT interference terms. The analyzed data were part of experiment E01-004 (Fπ-2), which used 2.6-5.2 GeV electron beams and HMS+SOS spectrometers in Jefferson Lab Hall C. The primary objective was to detect coincidence π in the forward-angle, where the backward-angle omega events were fortuitously detected. The experiment has central Q 2 values of 1.60 and 2.45 GeV 2 , at W = 2.21 GeV. There was significant coverage in phi and epsilon, which allowed separation of σ T,L,LT,TT . The data set has a unique u coverage of -u ~ 0, which corresponds to -t > 4 GeV 2 . The separated σ T result suggest a flat ~ 1/Q 1.33±1.21 dependence, whereas sigma_L seems to hold a stronger 1/Q 9.43±6.28 dependence. The σL/σ T ratio indicate σ T dominance at Q 2 = 2.45 GeV 2 at the ~90% confidence level. After translating the results into the -t space of the published CLAS data, our data show evidence of a backward-angle omega electroproduction peak at both Q 2 settings. Previously, this phenomenon showing both forward and backward-angle peaks was only observed in the meson photoproduction data. Through comparison of our σ T data with the prediction of the Transition Distribution Amplitude (TDA) model, and signs

  7. Remote logo detection using angle-distance histograms

    NASA Astrophysics Data System (ADS)

    Youn, Sungwook; Ok, Jiheon; Baek, Sangwook; Woo, Seongyoun; Lee, Chulhee

    2016-05-01

    Among all the various computer vision applications, automatic logo recognition has drawn great interest from industry as well as various academic institutions. In this paper, we propose an angle-distance map, which we used to develop a robust logo detection algorithm. The proposed angle-distance histogram is invariant against scale and rotation. The proposed method first used shape information and color characteristics to find the candidate regions and then applied the angle-distance histogram. Experiments show that the proposed method detected logos of various sizes and orientations.

  8. Apparent and microscopic dynamic contact angles in confined flows

    NASA Astrophysics Data System (ADS)

    Omori, Takeshi; Kajishima, Takeo

    2017-11-01

    An abundance of empirical correlations between a dynamic contact angle and a capillary number representing a translational velocity of a contact line have been provided for the last decades. The experimentally obtained dynamic contact angles are inevitably apparent contact angles but often undistinguished from microscopic contact angles formed right on the wall. As Bonn et al. ["Wetting and spreading," Rev. Mod. Phys. 81, 739-805 (2009)] pointed out, however, most of the experimental studies simply report values of angles recorded at some length scale which is quantitatively unknown. It is therefore hard to evaluate or judge the physical validity and the generality of the empirical correlations. The present study is an attempt to clear this clutter regarding the dynamic contact angle by measuring both the apparent and the microscopic dynamic contact angles from the identical data sets in a well-controlled manner, by means of numerical simulation. The numerical method was constructed so that it reproduced the fine details of the flow with a moving contact line predicted by molecular dynamics simulations [T. Qian, X. Wang, and P. Sheng, "Molecular hydrodynamics of the moving contact line in two-phase immiscible flows," Commun. Comput. Phys. 1, 1-52 (2006)]. We show that the microscopic contact angle as a function of the capillary number has the same form as Blake's molecular-kinetic model [T. Blake and J. Haynes, "Kinetics of liquid/liquid displacement," J. Colloid Interface Sci. 30, 421-423 (1969)], regardless of the way the flow is driven, the channel width, the mechanical properties of the receding fluid, and the value of the equilibrium contact angle under the conditions where the Reynolds and capillary numbers are small. We have also found that the apparent contact angle obtained by the arc-fitting of the interface behaves surprisingly universally as claimed in experimental studies in the literature [e.g., X. Li et al., "An experimental study on dynamic pore

  9. Incident Angle of Saltating Particles in Wind-Blown Sand

    PubMed Central

    Fu, Lin-Tao; Bo, Tian-Li; Gu, Hai-Hua; Zheng, Xiao-Jing

    2013-01-01

    Incident angle of saltating particles plays a very important role in aeolian events. In this paper, the incident angles of sand particles near the sand bed were measured in wind tunnel. It reveals that the incident angles range widely from 0° to 180° and thereby the means of angles are larger than published data. Surprisingly, it is found the proportion that angles of 5°–15° occupy is far below previous reports. The measuring height is probably the most important reason for the measurement differences between this study and previous investigations. PMID:23874470

  10. Predictors of Intraocular Pressure After Phacoemulsification in Primary Open-Angle Glaucoma Eyes with Wide Versus Narrower Angles (An American Ophthalmological Society Thesis)

    PubMed Central

    Lin, Shan C.; Masis, Marisse; Porco, Travis C.; Pasquale, Louis R.

    2017-01-01

    Purpose To assess if narrower-angle status and anterior segment optical coherence tomography (AS-OCT) parameters can predict intraocular pressure (IOP) drop in primary open-angle glaucoma (POAG) patients after cataract surgery. Methods This was a prospective case series of consecutive cataract surgery patients with POAG and no peripheral anterior synechiae (PAS) using a standardized postoperative management protocol. Preoperatively, patients underwent gonioscopy and AS-OCT. The same glaucoma medication regimen was resumed by 1 month. Potential predictors of IOP reduction included narrower-angle status by gonioscopy and angle-opening distance (AOD500) as well as other AS-OCT parameters. Mixed-effects regression adjusted for use of both eyes and other potential confounders. Results We enrolled 66 eyes of 40 glaucoma patients. The IOP reduction at 1 year was 4.2±3 mm Hg (26%, P<.001) in the narrower-angle group vs 2.2±3 mm Hg (14%, P<.001) in the wide-angle group (P=.027 for difference), as classified by gonioscopy. By AOD500 classification, the narrower-angle group had 3.4±3 mm Hg (21%, P<.001) reduction vs 2.5±3 mm Hg (16%, P<.001) in the wide-angle group (P=.031 for difference). When the entire cohort was assessed, iris thickness, iris area, and lens vault were correlated with increasing IOP reduction at 1 year (P<.05 for all). Conclusions In POAG eyes, cataract surgery lowered IOP to a greater degree in the narrower-angle group than in the wide-angle group, and parameters relating to iris thickness and area, as well as lens vault, were correlated with IOP reduction. These findings can guide ophthalmologists in their selection of cataract surgery as a potential management option. PMID:29147104

  11. Predictors of Intraocular Pressure After Phacoemulsification in Primary Open-Angle Glaucoma Eyes with Wide Versus Narrower Angles (An American Ophthalmological Society Thesis).

    PubMed

    Lin, Shan C; Masis, Marisse; Porco, Travis C; Pasquale, Louis R

    2017-08-01

    To assess if narrower-angle status and anterior segment optical coherence tomography (AS-OCT) parameters can predict intraocular pressure (IOP) drop in primary open-angle glaucoma (POAG) patients after cataract surgery. This was a prospective case series of consecutive cataract surgery patients with POAG and no peripheral anterior synechiae (PAS) using a standardized postoperative management protocol. Preoperatively, patients underwent gonioscopy and AS-OCT. The same glaucoma medication regimen was resumed by 1 month. Potential predictors of IOP reduction included narrower-angle status by gonioscopy and angle-opening distance (AOD500) as well as other AS-OCT parameters. Mixed-effects regression adjusted for use of both eyes and other potential confounders. We enrolled 66 eyes of 40 glaucoma patients. The IOP reduction at 1 year was 4.2±3 mm Hg (26%, P <.001) in the narrower-angle group vs 2.2±3 mm Hg (14%, P <.001) in the wide-angle group ( P =.027 for difference), as classified by gonioscopy. By AOD500 classification, the narrower-angle group had 3.4±3 mm Hg (21%, P <.001) reduction vs 2.5±3 mm Hg (16%, P <.001) in the wide-angle group ( P =.031 for difference). When the entire cohort was assessed, iris thickness, iris area, and lens vault were correlated with increasing IOP reduction at 1 year ( P <.05 for all). In POAG eyes, cataract surgery lowered IOP to a greater degree in the narrower-angle group than in the wide-angle group, and parameters relating to iris thickness and area, as well as lens vault, were correlated with IOP reduction. These findings can guide ophthalmologists in their selection of cataract surgery as a potential management option.

  12. Non-contact measurement of rotation angle with solo camera

    NASA Astrophysics Data System (ADS)

    Gan, Xiaochuan; Sun, Anbin; Ye, Xin; Ma, Liqun

    2015-02-01

    For the purpose to measure a rotation angle around the axis of an object, a non-contact rotation angle measurement method based on solo camera was promoted. The intrinsic parameters of camera were calibrated using chessboard on principle of plane calibration theory. The translation matrix and rotation matrix between the object coordinate and the camera coordinate were calculated according to the relationship between the corners' position on object and their coordinates on image. Then the rotation angle between the measured object and the camera could be resolved from the rotation matrix. A precise angle dividing table (PADT) was chosen as the reference to verify the angle measurement error of this method. Test results indicated that the rotation angle measurement error of this method did not exceed +/- 0.01 degree.

  13. Contact angle of unset elastomeric impression materials.

    PubMed

    Menees, Timothy S; Radhakrishnan, Rashmi; Ramp, Lance C; Burgess, John O; Lawson, Nathaniel C

    2015-10-01

    Some elastomeric impression materials are hydrophobic, and it is often necessary to take definitive impressions of teeth coated with some saliva. New hydrophilic materials have been developed. The purpose of this in vitro study was to compare contact angles of water and saliva on 7 unset elastomeric impression materials at 5 time points from the start of mixing. Two traditional polyvinyl siloxane (PVS) (Aquasil, Take 1), 2 modified PVS (Imprint 4, Panasil), a polyether (Impregum), and 2 hybrid (Identium, EXA'lence) materials were compared. Each material was flattened to 2 mm and a 5 μL drop of distilled water or saliva was dropped on the surface at 25 seconds (t0) after the start of mix. Contact angle measurements were made with a digital microscope at initial contact (t0), t1=2 seconds, t2=5 seconds, t3=50% working time, and t4=95% working time. Data were analyzed with a generalized linear mixed model analysis, and individual 1-way ANOVA and Tukey HSD post hoc tests (α=.05). For water, materials grouped into 3 categories at all time-points: the modified PVS and one hybrid material (Identium) produced the lowest contact angles, the polyether material was intermediate, and the traditional PVS materials and the other hybrid (EXA'lence) produced the highest contact angles. For saliva, Identium, Impregum, and Imprint 4 were in the group with the lowest contact angle at most time points. Modified PVS materials and one of the hybrid materials are more hydrophilic than traditional PVS materials when measured with water. Saliva behaves differently than water in contact angle measurement on unset impression material and produces a lower contact angle on polyether based materials. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  14. Estimating Elevation Angles From SAR Crosstalk

    NASA Technical Reports Server (NTRS)

    Freeman, Anthony

    1994-01-01

    Scheme for processing polarimetric synthetic-aperture-radar (SAR) image data yields estimates of elevation angles along radar beam to target resolution cells. By use of estimated elevation angles, measured distances along radar beam to targets (slant ranges), and measured altitude of aircraft carrying SAR equipment, one can estimate height of target terrain in each resolution cell. Monopulselike scheme yields low-resolution topographical data.

  15. Metasurface-based angle-selective multichannel acoustic refractor

    NASA Astrophysics Data System (ADS)

    Liu, Bingyi; Jiang, Yongyuan

    2018-05-01

    We theoretically study the angle-selective refractions of an impedance-matched acoustic gradient-index metasurface, which is integrated with a rigid bar array of a deep subwavelength period. An interesting refraction order appears under the all-angle incidence despite the existence of a critical angle, and notably, the odevity of the phase-discretization level apparently selects the transmitted diffraction orders. We utilize the strategy of multilayered media design to realize a three-channel acoustic refractor, which shows good promise for constructing multifunctional diffractive acoustic elements for acoustic communication.

  16. Evaluation of the Anterior Segment Angle-to-Angle Scan of Cirrus High-Definition Optical Coherence Tomography and Comparison With Gonioscopy and With the Visante OCT.

    PubMed

    Tun, Tin A; Baskaran, Mani; Tan, Shayne S; Perera, Shamira A; Aung, Tin; Husain, Rahat

    2017-01-01

    To evaluate the diagnostic performance of the anterior segment angle-to-angle scan of the Cirrus high-definition optical coherence tomography (HD-OCT) in detecting eyes with closed angles. All subjects underwent dark-room gonioscopy by an ophthalmologist. A technician performed anterior segment imaging with Cirrus (n = 202) and Visante OCT (n = 85) under dark-room conditions. All eyes were categorized by two masked graders as per number of closed quadrants. Each quadrant of anterior chamber angle was categorized as a closed angle if posterior trabecular meshwork could not be seen on gonioscopy or if there was any irido-corneal contact anterior to scleral spur in Cirrus and Visante images. An eye was graded as having a closed angle if two or more quadrants were closed. Agreement and area under the curve (AUC) were performed. There were 50 (24.8%) eyes with closed angles. The agreements of closed-angle diagnosis (by eye) between Cirrus HD-OCT and gonioscopy (k = 0.59; 95% confidence interval (CI) 0.45-0.72; AC1 = 0.76) and between Cirrus and Visante OCT (k = 0.65; 95% CI 0.48-0.82, AC1 = 0.77) were moderate. The AUC for diagnosing the eye with gonioscopic closed angle by Cirrus HD-OCT was good (AUC = 0.86; sensitivity = 83.33; specificity = 77.78). The diagnostic performance of Cirrus HD-OCT in detecting the eyes with closed angles was similar to that of Visante (AUC 0.87 vs. 0.9, respectively; P = 0.51). The anterior segment angle-to-angle scans of Cirrus HD-OCT demonstrated similar diagnostic performance as Visante in detecting gonioscopic closed angles. The agreement between Cirrus and gonioscopy for detecting eyes with closed angles was moderate.

  17. [Anatomy of fractures of the inferior scapular angle].

    PubMed

    Bartoníček, J; Tuček, M; Malík, J

    2018-01-01

    The aim of this study is to describe the anatomy of fractures of the inferior angle and the adjacent part of the scapular body, based on 3D CT reconstructions. In a series of 375 scapular fractures, we identified a total of 20 fractures of the inferior angle of the scapular body (13 men, 7 women), with a mean patient age of 50 years (range 3373). In all fractures, 3D CT reconstructions were obtained, allowing an objective evaluation of the fracture pattern with a focus on the size and shape of the inferior angle fragment, propagation of the fracture line to the lateral and medial borders of the infraspinous part of the scapular body, fragment displacement and any additional fracture of the ipsilateral scapula and the shoulder girdle. We identified a total of 5 types of fracture involving the distal half of the infraspinous part of the scapular body. The first type, recorded in 5 cases, affected only the apex of the inferior angle, with a small part of the adjacent medial border. The second type, occurring in 4 cases, involved fractures separating the entire inferior angle. The third type, represented by 4 cases, was characterized by a fracture line starting medially close above the inferior angle and passing proximolaterally. The separated fragment had a shape of a big drop, carrying also the distal half of the lateral pillar in addition to the inferior angle. In the fourth type identified in 5 fractures, the separated fragment was formed both by the inferior angle and a variable part of the medial border. The fifth type, being by its nature a transition to the fracture of the infraspinous part of the body, was recorded in 2 cases, with the same V-shaped fragment. Fractures of the inferior angle and the adjacent part of the scapular body are groups of fractures differing from other infraspinous fractures of the scapular body. Although these fractures are highly variable in terms of shape, they have the same course of fracture line and the manner of displacement

  18. Sun-view angle effects on reflectance factors of corn canopies

    NASA Technical Reports Server (NTRS)

    Ranson, K. J.; Daughtry, C. S. T.; Biehl, L. L.; Bauer, M. E.

    1985-01-01

    The effects of sun and view angles on reflectance factors of corn (Zea mays L.) canopies ranging from the six leaf stage to harvest maturity were studied on the Purdue University Agronomy Farm by a multiband radiometer. The two methods of acquiring spectral data, the truck system and the tower systrem, are described. The analysis of the spectral data is presented in three parts: solar angle effects on reflectance factors viewed at nadir; solar angle effects on reflectance factors viewed at a fixed sun angle; and both sun and view angles effect on reflectance factors. The analysis revealed that for nadir-viewed reflectance factors there is a strong solar angle dependence in all spectral bands for canopies with low leaf area index. Reflectance factors observed from the sun angle at different view azimuth angles showed that the position of the sensor relative to the sun is important in determining angular reflectance characteristics. For both sun and view angles, reflectance factors are maximized when the sensor view direction is towards the sun.

  19. Effect of nanoparticle size on sessile droplet contact angle

    NASA Astrophysics Data System (ADS)

    Munshi, A. M.; Singh, V. N.; Kumar, Mukesh; Singh, J. P.

    2008-04-01

    We report a significant variation in the static contact angle measured on indium oxide (IO) nanoparticle coated Si substrates that have different nanoparticle sizes. These IO nanoparticles, which have well defined shape and sizes, were synthesized by chemical vapor deposition in a horizontal alumina tube furnace. The size of the IO nanoparticles was varied by changing the source material, substrate temperature, and the deposition time. A sessile droplet method was used to determine the macroscopic contact angle on these IO nanoparticle covered Si substrate using two different liquids: de-ionized water and diethylene glycol (DEG). It was observed that contact angle depends strongly on the nanoparticle size. The contact angle was found to vary from 24° to 67° for de-ionized water droplet and from 15° to 60° for DEG droplet, for the nanoparticle sizes varying from 14 to 620 nm. The contact angle decreases with a decrease in the particles size. We have performed a theoretical analysis to determine the dependence of contact angle on the nanoparticle size. This formulation qualitatively shows a similar trend of decrease in the contact angle with a decrease in nanoparticle size. Providing a rough estimate of nanoparticle size by sessile droplet contact angle measurement is the novelty in this work.

  20. Effect of Angle of Attack on Slope Climbing Performance

    NASA Technical Reports Server (NTRS)

    Creager, Colin M.; Jones, Lucas; Smith, Lauren M.

    2017-01-01

    Ascending steep slopes is often a very difficult challenge for off-road vehicles, whether on Earth or on extraterrestrial bodies. This challenge is even greater if the surface consists of loose granular soil that does not provide much shear strength. This study investigated how the path at which a vehicle traverses a slope, specifically the angle that it is commanded to drive relative to the base of the hill (the angle of attack), can affect its performance. A vehicle was driven in loose sand at slope angles up to 15 degrees and angles of attack ranging from 10 to 90 degrees. A novel photogrammetry technique was implemented to both track vehicle motion and create a three-dimensional profile of the terrain. This allowed for true wheel sinkage measurements. The study showed that though low angles of attack result in lower wheel slip and sinkage, the efficiency of the vehicles uphill motion increased at higher angles of attack. For slopes up to 15 degrees, a 90 degree angle of attack provided the greatest likelihood of successful ascent.