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Sample records for 9-year-old posterior-stabilized knee

  1. Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

    PubMed Central

    Zhao, Zhi-Xin; Wen, Liang; Qu, Tie-Bing; Hou, Li-Li; Xiang, Dong; Bin, Jia

    2015-01-01

    Background: The goal of total knee arthroplasty (TKA) is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS) knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0–135° flexion. Results: Both the output data trends and the measured values derived from the normal knee's kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, “rollback” compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis. PMID:25591565

  2. Posterior cruciate ligament removal contributes to abnormal knee motion during posterior stabilized total knee arthroplasty.

    PubMed

    Cromie, Melinda J; Siston, Robert A; Giori, Nicholas J; Delp, Scott L

    2008-11-01

    Abnormal anterior translation of the femur on the tibia has been observed in mid flexion (20-60 degrees ) following posterior stabilized total knee arthroplasty. The underlying biomechanical causes of this abnormal motion remain unknown. The purpose of this study was to isolate the effects of posterior cruciate ligament removal on knee motion after total knee arthroplasty. We posed two questions: Does removing the posterior cruciate ligament introduce abnormal anterior femoral translation? Does implanting a posterior stabilized prosthesis change the kinematics from the cruciate deficient case? Using a navigation system, we measured passive knee kinematics of ten male osteoarthritic patients during surgery after initial exposure, after removing the anterior cruciate ligament, after removing the posterior cruciate ligament, and after implanting the prosthesis. Passively flexing and extending the knee, we calculated anterior femoral translation and the flexion angle at which femoral rollback began. Removing the posterior cruciate ligament doubled anterior translation (from 5.1 +/- 4.3 mm to 10.4 +/- 5.1 mm) and increased the flexion angle at which femoral rollback began (from 31.2 +/- 9.6 degrees to 49.3 +/- 7.3 degrees). Implanting the prosthesis increased the amount of anterior translation (to 16.1 +/- 4.4 mm), and did not change the flexion angle at which femoral rollback began. Abnormal anterior translation was observed in low and mid flexion (0-60 degrees) after removing the posterior cruciate ligament, and normal motion was not restored by the posterior stabilized prosthesis.

  3. In vivo polyethylene bearing mobility is maintained in posterior stabilized total knee arthroplasty.

    PubMed

    Komistek, Richard D; Dennis, Douglas A; Mahfouz, Mohamed R; Walker, Scott; Outten, Joel

    2004-11-01

    In vivo knee kinematics, including polyethylene bearing mobility, were determined in a group of nine patients implanted with a posterior stabilized, mobile-bearing total knee arthroplasty. Each patient, while under fluoroscopic surveillance, did a weightbearing deep knee bend and was analyzed using a 3-D computer model-fitting technique. Patients were evaluated at three and 15 months postoperatively. All nine patients had polyethylene bearing rotation relative to the tibial tray at both times, with the maximum amount of polyethylene bearing rotation at any flexion interval averaging 8.5 (range, 5.2-15.5) and 9.8 (range, 4.8-14.2) at 3 and 15 months, respectively. Minimal rotation of the polyethylene bearing relative to the femoral component was observed, averaging only 1.9 and 1.0 of rotation from full extension to maximum knee flexion at three and 15 months, respectively. This study determined that the polyethylene bearing is primarily rotating relative to the tibia rather than the femoral component. Therefore, as the femoral component axially rotates, the polyethylene bearing is rotating a similar magnitude in the same direction. This should result in reduced shear stresses on the superior aspect of the polyethylene bearing, lessening polyethylene wear.

  4. Patient function after a posterior stabilizing total knee arthroplasty: cam-post engagement and knee kinematics.

    PubMed

    Suggs, Jeremy F; Hanson, George R; Park, Sang Eun; Moynihan, Angela L; Li, Guoan

    2008-03-01

    Even though posterior substituting total knee arthroplasty has been widely used in surgery, how the cam-post mechanism (posterior substituting mechanism) affects knee joint kinematics and function in patients is not known. The objective of the present study was to investigate posterior femoral translation, internal tibial rotation, tibiofemoral contact, and cam-post engagement of total knee arthroplasty patients during in vivo weight-bearing flexion. Twenty-four knees with a PS TKA were investigated while performing a single leg weight-bearing lunge from full extension to maximum flexion as images were recorded using a dual fluoroscopic system. The in vivo knee position at each targeted flexion angle was reproduced using 3D TKA models and the fluoroscopic images. The kinematics of the knee was measured from the series of the total knee arthroplasty models. The cam-post engagement was determined when the surface model of the femoral cam overlapped with that of the tibial post. The mean maximum flexion angle for all the subjects was 112.5 +/- 13.1 degrees . The mean flexion angle where cam-post engagement was observed was 91.1 +/- 10.9 degrees . The femur moved anteriorly from 0 degrees to 30 degrees and posteriorly through the rest of the flexion range. The internal tibial rotation increased approximately 6 degrees from full extension to 90 degrees of flexion and decreased slightly with further flexion. Both the medial and lateral contact point moved posteriorly from 0 degrees to 30 degrees , remained relatively constant from 30 degrees to 90 degrees , and then moved further posterior from 90 degrees to maximum flexion. The in vivo cam-post engagement corresponded to increased posterior translation and reduced internal tibial rotation at high flexion of the posterior substituting total knee arthroplasty. The initial cam-post engagement was also mildly correlated with the maximum flexion angle of the knee (R = 0.51, p = 0.019). A later cam-post engagement might

  5. Effect of femoral component design on patellofemoral crepitance and patella clunk syndrome after posterior-stabilized total knee arthroplasty.

    PubMed

    Frye, Benjamin M; Floyd, Mark W; Pham, Dahn C; Feldman, John J; Hamlin, Brian R

    2012-06-01

    The purpose of this study was to determine if recent changes to the femoral component of a particular posterior-stabilized total knee prosthesis would affect the incidence of postoperative patellofemoral crepitance and patella clunk syndrome. One hundred eight total knee arthroplasties were performed with the conventional design; 136 were performed after the femoral component was changed. Complications were compared between the groups with an average follow-up of 17.7 months and 12.4 months, respectively. Thirteen knees with the conventional design (12%) were found to have patellofemoral complications; no complications were noted with the new design (P < .0001). Femoral components with a deep trochlear groove and smooth transition of the intercondylar box appear to better accommodate any peripatellar fibrous nodule that may form after total knee arthroplasty.

  6. Does Cruciate-Retaining Total Knee Arthroplasty Show Better Quadriceps Recovery than Posterior-Stabilized Total Knee Arthroplasty? - Objective Measurement with a Dynamometer in 102 Knees

    PubMed Central

    Cho, Kye-Youl; Song, Sang-Jun; Bae, Dae-Kyung

    2016-01-01

    Background Cruciate-retaining (CR) prostheses have been considered to produce more physiologic femoral rollback, provide better proprioception, and result in better quadriceps recovery than posterior-stabilized (PS) prostheses after total knee arthroplasty (TKA). However, there are very few studies demonstrating these benefits in an objective manner. We investigated whether CR-TKA could result in (1) better quadriceps recovery; (2) a greater proportion of patients with beyond the preoperative level of recovery; and (3) better clinical outcomes than PS-TKA. Methods This was a prospective non-randomized comparative study on the results of CR-TKA and PS-TKA. CR prostheses were used in 51 knees and PS prostheses in 51 knees. Quadriceps force was measured with a dynamometer preoperatively and at postoperative 6 weeks, 3 months, and 6 months consecutively. The Knee Society score (KSS) and range of motion (ROM) were also evaluated. Results There were no differences between two groups in terms of the objective quadriceps force during the follow-up period. The proportion of patients with beyond the preoperative level of recovery was similar between groups. Moreover, the KSS and ROM were not significantly different between two groups. Conclusions CR-TKA did not result in better quadriceps recovery than PS-TKA during the 6-month follow-up. In other words, PS-TKA could lead to comparable quadriceps recovery despite greater preoperative weaknesses such as more restricted ROM and more severe degenerative changes of the knee. PMID:27904719

  7. Fracture of the polyethylene tibial post in a posterior stabilized knee prosthesis: A case report and review of literature.

    PubMed

    Kumar, Nishikant; Yadav, Chandrashekhar; Raj, Rishi; Yadav, Sanjay

    2015-09-01

    We report a case of fracture of tibial polyethylene post fracture from base in a 56 year old lady 10 years from posterior stabilized total knee arthroplasty following trivial trauma. There have been signs of wear at the base especially anteriorly. After revision of tibial polyethylene component patient developed complete relief of symptom.

  8. Highly Cross-Linked Versus Conventional Polyethylene in Posterior-Stabilized Total Knee Arthroplasty at a Mean 5-Year Follow-up.

    PubMed

    Meneghini, R Michael; Lovro, Luke R; Smits, Shelly A; Ireland, Philip H

    2015-10-01

    Concerns of highly cross-linked polyethylene (XLPE) in total knee arthroplasty (TKA) exist regarding fatigue resistance and oxidation, particularly in posterior-stabilized (PS) designs. A prospective cohort study of 114 consecutive PS TKAs utilized conventional polyethylene in 50 knees and second-generation annealed XLPE in 64 TKAs. Clinical (Short-Form 36, Knee Society Scores, and LEAS) and radiographic outcomes were evaluated at a mean of 5 years in 103 TKAs. Mean KSS scores were 12 points higher (P=0.01) and SF-36 physical function subset 14 points higher (P=0.005) in the XLPE group. There was no radiographic osteolysis or mechanical failure related to the tibial polyethylene in either group. At 5-year follow-up, no deleterious effects related to highly cross-linked posterior stabilized tibial polyethylene inserts were observed.

  9. Incidence of patellar clunk syndrome in fixed versus high-flex mobile bearing posterior-stabilized total knee arthroplasty.

    PubMed

    Snir, Nimrod; Schwarzkopf, Ran; Diskin, Brian; Takemoto, Richelle; Hamula, Mathew; Meere, Patrick A

    2014-10-01

    The geometry of the intercondylar box plays a significant role in the development of patellar clunk syndrome. We reviewed the incidence of patella clunk at mid-to-long-term follow-up of a rotating high-flex versus fixed bearing posterior stabilized TKA design. 188-mobile and 223-fixed bearing TKAs were reviewed for complications, incidence of patellar clunk, treatment, recurrence rates, range of motion, and patient satisfaction. Patellar clunk developed in 22 knees in the mobile (11.7%) and in 4 (1.8%) in the fixed bearing group (P<0.001). 23 out of 26 cases resolved with a single arthroscopic treatment and 2 resolved with a second procedure. The mean postoperative range of motion was 122.4°. All but one patient reported overall satisfaction with the index procedure. In contrast with other recent studies we found a significant incidence of patellar clunk in high-flex mobile bearings. Despite the high rate of patellar clunk syndrome, overall patients did well and were satisfied with their outcomes.

  10. What have we learned from 100% success of press fit condylar rotating platform posterior stabilized knees?: A 5-10 years followup by a nondesigner

    PubMed Central

    Vaidya, Shrinand V; Virani, Siddharth; Phunde, Rajendra; Mahajan, Abhishek

    2016-01-01

    Background: Total joint arthroplasties of the hip and knee represent a remarkable feat of modern medicine in terms of reducing pain and restoring function to millions of patients afflicted with severe arthritis. Oftentimes, the performance and longevity of new implants and devices are based on limited data. This is the first study by a non-designer on the press fit condylar rotating platform posterior stabilized (PFC-RP-PS) design with 100’ success. This has a relevance, vis-á -vis bias that one may have in terms of reproducibility of technique and funding from the manufacturer. We associate our excellent mid-term results to intra operative technical aspects and stringent intra operative exclusion criteria. Materials and Methods: Our study includes a cohort of 121 selected knees operated between January 2003 and October 2010. We used cemented, posterior stabilized (PS), mobile bearing (MB), and RP prosthesis from the same manufacturer in all these 121 knees. The patients were evaluated bi-annually with the calculation of their Knee Society Scores (KSS) and a radiological assessment for loosening/osteolysis. Results: 120 knees were available for followup. The average Knee Society clinical and functional scores, respectively, were 27 points and 40 points preoperatively and 93 points and 95 points postoperatively. This indicates a mean increase of about 71’ in the clinical score and about 58’ in the functional score, which is statistically significant. The mean postoperative flexion was 124°, a mean increase of 23° from the preoperative flexion of 101°. There were no revisions (Kaplan-–Meier survivorship of 100’). Conclusions: We feel durable and reproducible results of PFC-RP-PS design knees are very technique sensitive. The way ahead with the PFC-RP-PS knees looks promising when the exclusion criteria for this design are strictly met. Coming from a non-designer, this study acquires a higher degree of relevance without any designer's or manufacturer

  11. Revision Total Knee Arthroplasty with a Cemented Posterior Stabilized, Condylar Constrained or Fully Constrained Prosthesis: A Minimum 2-year Follow-up Analysis

    PubMed Central

    Hwang, Sun-Chul; Kong, Jae-Yeon; Nam, Dae-Cheol; Kim, Dong-Hee; Park, Hyung-Bin; Jeong, Soon-Taek

    2010-01-01

    Background The clinical and radiological outcomes of revision total knee arthroplasty with a cemented posterior stabilized (PS), condylar constrained knee (CCK) or a fully constrained rotating hinge knee (RHK) prosthesis were evaluated. Methods This study reviewed the clinical and radiological results of 36 revision total knee arthroplasties with a cemented PS, CCK, and RHK prosthesis in 8, 25, and 13 cases, respectively, performed between 1998 and 2006. The mean follow-up period was 30 months (range, 24 to 100 months). The reason for the revision was aseptic loosening of one or both components in 15, an infected total knee in 18 and a periprosthetic fracture in 3 knees. The average age of the patients at the time of the revision was 65 years (range, 58 to 83 years). The original diagnosis for all primary total knee arthroplasties was osteoarthritis except for one case of a Charcot joint. All revision prostheses were fixed with cement. The bone deficiencies were grafted with a cancellous allograft in the contained defect and cortical allograft fixed with a plate and screws in the noncontained defect. A medial gastrocnemius flap was needed to cover the wound dehiscence in 6 of the 18 infected cases. Results The mean Knee Society knee score improved from 28 (range, 5 to 43) to 83 (range, 55 to 94), (p < 0.001) and the mean Knee Society function score improved from 42 (range, 10 to 66) to 82 (range, 60 to 95), (p < 0.001) at the final follow-up. Good or excellent outcomes were obtained in 82% of knees. There were 5 complications (an extensor mechanism rupture in 3 and recurrence of infection in 2 cases). Three cases of an extensor mechanism defect (two ruptures of ligamentum patellae and one patellectomy) were managed by the RHK prosthesis to provide locking stability in the heel strike and push off phases, and two cases of recurrent infection used an antibiotic impregnated cement spacer. The radiological tibiofemoral alignment improved from 1.7° varus to 3.0

  12. Evaluation of Postoperative Range of Motion and Functional Outcomes after Cruciate-Retaining and Posterior-Stabilized High-Flexion Total Knee Arthroplasty

    PubMed Central

    Han, Chang Wook; Yang, Ick Hwan; Lee, Woo Suk; Park, Kwan Kyu

    2012-01-01

    Purpose The purpose of this study was to compare postoperative range of motion and functional outcomes among patients who received high-flexion total knee arthroplasty using cruciate-retaining (CR-Flex) and posterior-stabilized (PS-Flex) type prostheses. Materials and Methods Among 127 patients (186 knees) who underwent high-flexion total knee arthroplasty between 2005 and 2007, 92 knees were placed in the CR-Flex group, and 94 knees were placed in the PS-Flex group. After two years of postoperative follow-up, clinical and radiographic data were reviewed. Postoperative non-weight-bearing range of knee motion, angle of flexion contracture and functional outcomes based on the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) functional sub-scale were assessed and compared between the two groups. Results After the 2-year postoperative period, the mean range of motion was 131° in the CR-Flex group and 133° in the PS-Flex group. There were no significant differences in postoperative range of motion between the two groups. Only age at operation and preoperative range of motion were significantly associated with postoperative range of motion after high-flexion total knee arthroplasty. Postoperative functional outcomes based on the WOMAC functional sub-scale were slightly better in the CR-Flex group (9.2±9.1 points) than in the PS-Flex group (11.9±9.6 points); however, this difference was not statistically significant (p=non-significant). Conclusion The retention or substitution of the posterior cruciate ligament does not affect postoperative range of motion (ROM) or functional outcomes, according to 2 years of postoperative follow-up of high-flexion total knee arthroplasty. PMID:22665348

  13. Clinical evaluation of 292 Genesis II posterior stabilized high-flexion total knee arthroplasty: range of motion and predictors.

    PubMed

    Fuchs, Mathijs C H W; Janssen, Rob P A

    2015-01-01

    The primary aim of the study was to evaluate the range of motion and complications after Genesis II total knee arthroplasty with high-flexion tibia insert (TKA-HF). Furthermore, difference in knee flexion between high flexion and standard inserts was compared. The hypothesis was that knee flexion is better after high-flexion TKA. A total of 292 TKA-HF were retrospectively reviewed. Mean follow-up was 24.3 months. The range of motion was compared between TKA-HF (high-flexion group) and a comparable cohort of 86 Genesis II TKA with a standard tibia insert (control group). Surgeries were performed by one experienced knee orthopedic surgeon. Knee flexion in the high-flexion group increased from 114.8° preoperatively to 118.0° postoperatively (P < 0.01). Knee extension in the high-flexion group increased from -4.5° preoperatively to -0.4° after surgery (P < 0.01). Mean knee flexion was 5.52° (± 1.46°) better in the high-flexion group compared with the control group (P < 0.01). Preoperative range of motion, body mass index, diabetes mellitus and patellofemoral pain significantly influenced range of motion. Few complications occurred after TKA-HF. The Genesis II TKA-HF showed good short-term results with limited complications. Knee flexion after Genesis II TKA-HF was better compared with a standard tibia insert.

  14. Tibiofemoral alignment in posterior stabilized total knee arthroplasty: Static alignment does not predict dynamic tibial plateau loading.

    PubMed

    Miller, Emily J; Pagnano, Mark W; Kaufman, Kenton R

    2014-08-01

    For total knee arthroplasty (TKA), neutral mechanical alignment produces balanced static knee loading. Dynamically, knee loading is affected by more than limb static alignment. We compared static and dynamic knee loading following TKA. Fifteen TKA patients were evaluated pre-operatively and 2 months and 2 years post-operatively. Tibiofemoral angles and medial tibial plateau loading were calculated. Pre-operatively, static medial load was greater for varus than valgus knees. Post-operatively, no relationship existed between tibiofemoral angle and static medial plateau load. Pre-operatively and post-operatively, dynamic medial load was not dependent on tibiofemoral angle. While all patients achieved equal static plateau load distributions at 2 years, only 47% had dynamic medial load distributions of 50 ± 10%. Static tibiofemoral alignment alone does not predict dynamic tibial loading.

  15. 180° rotatory dislocation of the rotating platform of a posterior-stabilized mobile-bearing knee prosthesis; possible complication after closed reduction of a posterior dislocation--a case report.

    PubMed

    Lee, Ho Min; Kim, Young Sung; Kim, Jong Pil

    2014-01-01

    Dislocation of the rotating platform is a significant early complication of mobile-bearing total knee arthroplasty. The authors report an unusual case of acute 180° rotatory dislocation of the rotating platform after closed reduction of a posterior dislocation of a posterior-stabilized mobile-bearing total knee prosthesis. A 71-year-old male with knee osteoarthritis underwent TKRA using a posterior-stabilized mobile-bearing prosthesis. Posterior dislocation of the prosthesis occurred at 5 weeks postoperatively, and closed reduction of the posterior dislocation resulted in complete 180° rotatory dislocation of the rotating platform. The patient was treated by open exploration and polyethylene exchange for a larger component. This case illustrates that dislocation of a posterior-stabilized mobile-bearing total knee prosthesis can occur given valgus laxity and causes a 90° spin-out of the polyethylene insert, and that closed reduction attempts may contribute to complete 180° rotatory dislocation of the rotating platform. Special attention should be given to both AP and lateral views to ensure that the platform is truly reduced and not rotated by 180°. Plain digital radiography, which enhances the density of polyethylene, or arthrography is helpful for diagnosing this complication.

  16. Obturator externus abscess in a 9-year-old child

    PubMed Central

    de Bodman, Charlotte; Ceroni, Dimitri; Dufour, Justine; Crisinel, Pierre-Alex; Bregou-Bourgeois, Aline; Zambelli, Pierre-Yves

    2017-01-01

    Abstract Rationale: Obturator pyomyositis is a rare condition in children. Diagnosis is often delayed because of its rarity, and the vagaries of its presentation cause it to be easily be missed. Physicians should therefore familiarize themselves with this condition and consider it as a possible differential diagnosis in patients presenting with an acutely painful hip. Inflammatory syndrome is also frequent among sufferers and the MRI is a very sensitive diagnostic tool for obturator pyomyositis. Additionally, joint fluid aspirations and blood cultures are also useful in identifying the pathogen. The appropriate antibiotic therapy provides a rapid regression of symptoms during the early stage of pyomyositis. In cases of MRI-confirmed abscess, surgical treatment is indicated. Patient concerns: Our report focuses on a case of obturator pyomyositis in a 9-year-old boy. The child was febrile for 5 days and could only manage to walk a few steps. His hip range of motion was restricted in all directions. In addition, the patient had presented pain and swelling of his right elbow for a day, with a restriction of motion in the joint. There was a clear inflammatory syndrome. A diagnosis of hip and elbow septic arthritis was suspected, and the child underwent joint aspiration of the both cited joints. The aspiration of the elbow returned pus. Conversely, no effusion was found in the hip aspiration. The administration of empiric intravenous antibiotherapy was started. Diagnoses: An MRI revealed an osteomyelitis of the ischio-pubic area associated with a subperiosteal abscess. Interventions: Subsequently, 3 days after elbow arthrotomy, a surgical treatment was performed on the patient's right hip in order to evacuate the subperiosteal abscess and muscular collection because of the persistence of the patient's symptoms and inflammatory syndrome despite susceptible intravenous antibiotics. Postsurgery the patient showed steady improvement. Lessons: Such cases demonstrate how

  17. Pharmacotherapy of Aggression in a 9-Year-Old with ADHD

    ERIC Educational Resources Information Center

    Findling, Robert L.; Newcorn, Jeffrey H.; Malone, Richard P.; Waheed, Ayesha; Prince, Jefferson B.; Kratochvil, Christopher J.

    2007-01-01

    A 9-year-old boy presents for assessment and treatment of his reactive, impulsive aggressive behavior that has been present for approximately 2 years. Six months ago, his pediatrician started treatment with OROS methylphenidate (MPH), which was titrated to 36 mg/day. There was moderate improvement in symptoms of attention-deficit/hyperactivity…

  18. Understanding Linear and Exponential Growth: Searching for the Roots in 6- To 9-Year-Olds

    ERIC Educational Resources Information Center

    Ebersbach, Mirjam; Van Dooren, Wim; Van den Noortgate, Wim; Resing, Wilma C. M.

    2008-01-01

    Previous studies have suggested that children as young as 9 years old have developed an understanding of non-linear growth processes prior to formal education. The present experiment aimed at investigating this competency in even younger samples (i.e., in kindergartners, first, and third graders, ages 6, 7 and 9, respectively). Children (N=90)…

  19. The Prevention of Depression in 8- to 9-Year-Old Children: A Pilot Study

    ERIC Educational Resources Information Center

    Rooney, Rosanna; Roberts, Clare; Kane, Robert; Pike, Lisbeth; Winsor, Amber; White, Julia; Brown, Annette

    2006-01-01

    The outcomes of a new universal program aimed at preventing depressive symptoms and disorders in 8- to 9-year-old children are presented. The Positive Thinking Program is a mental health promotion program based on cognitive and behavioural strategies. It is designed to meet the developmental needs of children in the middle primary school Years 4…

  20. Cognitive Components of a Mathematical Processing Network in 9-Year-Old Children

    ERIC Educational Resources Information Center

    Szucs, Dénes; Devine, Amy; Soltesz, Fruzsina; Nobes, Alison; Gabriel, Florence

    2014-01-01

    We determined how various cognitive abilities, including several measures of a proposed domain-specific number sense, relate to mathematical competence in nearly 100 9-year-old children with normal reading skill. Results are consistent with an extended number processing network and suggest that important processing nodes of this network are…

  1. Developmental Dyscalculia and Basic Numerical Capacities: A Study of 8--9-Year-Old Students

    ERIC Educational Resources Information Center

    Landerl, Karin; Bevan, Anna; Butterworth, Brian

    2004-01-01

    Thirty-one 8- and 9-year-old children selected for dyscalculia, reading difficulties or both, were compared to controls on a range of basic number processing tasks. Children with dyscalculia only had impaired performance on the tasks despite high-average performance on tests of IQ, vocabulary and working memory tasks. Children with reading…

  2. Context and Linguistic Politeness in 7- and 9-Year-Old Italian Children.

    ERIC Educational Resources Information Center

    Axia, Giovanna; Argenti, Emanuela

    The development of linguistic politeness in 7- and 9-year-old Italian children was examined. A total of 80 subjects, 40 males and 40 females, produced requests according to different contexts which were graphically presented. Factors considered for such contexts were: sex of the speaker; sex of the addressee; status of the addressee, either peer…

  3. The Great Recession and Behavior Problems in 9-Year Old Children

    ERIC Educational Resources Information Center

    Schneider, William; Waldfogel, Jane; Brooks-Gunn, Jeanne

    2015-01-01

    This article examines associations between the Great Recession and 4 aspects of 9-year olds' behavior--aggression (externalizing), anxiety/depression (internalizing), alcohol and drug use, and vandalism-using the Fragile Families and Child Wellbeing Study, a longitudinal birth cohort drawn from 20 U.S. cities (21% White, 50% Black, 26% Hispanic,…

  4. Analysis of surface damage in retrieved carbon fiber-reinforced and plain polyethylene tibial components from posterior stabilized total knee replacements.

    PubMed

    Wright, T M; Rimnac, C M; Faris, P M; Bansal, M

    1988-10-01

    The performance of carbon fiber-reinforced ultra-high molecular weight polyethylene was compared with that of plain (non-reinforced) polyethylene on the basis of the damage that was observed on the articulating surfaces of retrieved tibial components of total knee prostheses. Established microscopy techniques for subjectively grading the presence and extent of surface damage and the histological structure of the surrounding tissues were used to evaluate twenty-six carbon fiber-reinforced and twenty plain polyethylene components that had been retrieved after an average of twenty-one months of implantation. All of the tibial components were from the same design of total knee replacement. The two groups of patients from whom the components were retrieved did not differ with regard to weight, the length of time that the component had been implanted, the radiographic position and angular alignment of the component, the original diagnosis, or the reason for removal of the component. The amounts and types of damage that were observed did not differ for the two materials. For both materials, the amount of damage was directly related to the length of time that the component had been implanted. The histological appearance of tissues from the area around the component did not differ for the two materials, except for the presence of fragments of carbon fiber in many of the samples from the areas around carbon fiber-reinforced components.

  5. Occult fracture of the lesser tuberosity in a 9-year-old female swimmer

    PubMed Central

    Aagaard, KE; Lunsjö, K

    2017-01-01

    The adolescent avulsion of the lesser tuberosity of the humerus has historically been considered as very rare. The youngest patient reported in the literature is 11 years old. We report a case of a 9-year-old girl who suffered a subscapularis tendon tear with an occult avulsion of the lesser tuberosity. Late repair restored function. Despite that late repair in this present case resulted in excellent outcome, we strongly recommend the additional axillary lateral view of the plain radiographs, as well as proper physical examination to facilitate early diagnosis. PMID:28122897

  6. [Nasopharyngeal cyst of the respiratory epithelium in a 9-year-old Yorkshire terrier].

    PubMed

    Acker, Alexander; Thiel, Cetina; Köhler, Kernt; von Pückler, Kerstin; Moritz, Andreas; Kramer, Martin

    2017-02-23

    In a 9-year-old Yorkshire terrier a cyst of the respiratory epithelium of the nasopharynx was diagnosed. A complete obstruction of the nasopharynx leading to dyspnea was detected by computed tomography and endoscopy. A minimally invasive ablation of the cystic wall was performed under endoscopic guidance, followed by a pathohistological examination. Immediately after resection of the cyst, the clinical symptoms resolved. The follow-up endoscopical examination 3 months postoperatively was unremarkable. In the presented case the minimally invasive endoscopic ablation of the cystic wall was a successful treatment method.

  7. Subclavian vein thrombosis in an otherwise healthy 9-year-old boy

    PubMed Central

    Young, Katie; Tunstall, Oliver; Mumford, Andrew

    2014-01-01

    We report a previously well 9-year-old boy who presented with an acutely swollen left arm after horse riding. Left subclavian vein thrombosis was demonstrated by MR venography but there was no evidence of an underlying anatomical abnormality. The child was successfully treated with catheter directed thrombolysis and anticoagulation with intravenous unfractionated heparin and warfarin. We have identified 75 previously published case reports of effort-induced upper extremity deep vein thrombosis (UEDVT) and surveyed patient characteristics and precipitating activities. In this case and literature review, we demonstrate that individuals with effort-induced UEDVT show demographic characteristics and presenting features that are distinct from other patient groups with venous thromboembolic disease. We also highlight the difficulties in counselling affected individuals about modifying occupational and recreational activities to minimise the risk of recurrent thrombosis. PMID:24855075

  8. Cognitive components of a mathematical processing network in 9-year-old children.

    PubMed

    Szűcs, Dénes; Devine, Amy; Soltesz, Fruzsina; Nobes, Alison; Gabriel, Florence

    2014-07-01

    We determined how various cognitive abilities, including several measures of a proposed domain-specific number sense, relate to mathematical competence in nearly 100 9-year-old children with normal reading skill. Results are consistent with an extended number processing network and suggest that important processing nodes of this network are phonological processing, verbal knowledge, visuo-spatial short-term and working memory, spatial ability and general executive functioning. The model was highly specific to predicting arithmetic performance. There were no strong relations between mathematical achievement and verbal short-term and working memory, sustained attention, response inhibition, finger knowledge and symbolic number comparison performance. Non-verbal intelligence measures were also non-significant predictors when added to our model. Number sense variables were non-significant predictors in the model and they were also non-significant predictors when entered into regression analysis with only a single visuo-spatial WM measure. Number sense variables were predicted by sustained attention. Results support a network theory of mathematical competence in primary school children and falsify the importance of a proposed modular 'number sense'. We suggest an 'executive memory function centric' model of mathematical processing. Mapping a complex processing network requires that studies consider the complex predictor space of mathematics rather than just focusing on a single or a few explanatory factors.

  9. Cat scratch disease in 9-year-old patient - a case report.

    PubMed

    Świątkowski, Wojciech; Rahnama, Mansur; Strzelczyk, Katarzyna; Baszak, Jakub; Sierocińska-Sawa, Jadwiga

    2016-03-01

    Cat scratch disease (CSD) - bartonellosis, is zoonosis caused by the intracellular gram negativebacterium Bartonellahenselae or Bartonellaquintana. The pathogens of this disease enter the human body usually as a consequence of a bite or scratch by young cats which are the natural source of such bacteria. The illness proceeds asymptomatically or with topical symptoms of infection such as a lump, spot or blister. Within 14 days a high fever and topical lymphadenopathy are observed. Lymph nodes are sore and start suppurating. In half of patients, these symptoms may resemble malignancy, and in single cases there are symptoms associated with the musculoskeletal system, such as: osteitis, arthitis and myositis. In paper presented case of 9 year-old girl patients, treated in Oral Surgery Unit due to odema and lymphadenopathy in right submandibular space. Primary surgical treatment of deciduous teeth was conducted without recovery. In few months follow-up, biopsy of lymph node of submandibular group was taken and provisional diagnosis of cat scratch disease was set. Patient was referred to the Infectious Diseases Unit where serological test confirmed cat scratch disease, and pharmacological treatment was conducted with success and recovery of young patient.

  10. Obstacle crossing in 7-9-year-old children with Down syndrome.

    PubMed

    Chen, Hao-Ling; Yu, Wan-Hui; Yeh, Hsiu-Chen

    2016-01-01

    This study aimed to investigate obstacle crossing in 7-9-year-old children with Down syndrome (DS). Fifteen children with DS, age- and gender-matched with 15 typically developing (TD) children, were recruited to walk and cross obstacles with heights of 10%, 20% and 30% of their leg lengths. End-point and kinematic variables of obstacle crossing were obtained using a three-dimensional motion analysis system. The results showed that children with DS tend to adopt a lower speed and larger step width when they perceive instability. Moreover, unlike TD children, children with DS adopt a pelvic strategy (i.e., greater pelvic leading-side listing and forward rotation) to achieve a higher leading toe clearance with a longer step length, presumably for safety reasons. This pelvic strategy increased the frontal plane motion of the whole leg and trunk, and thus possibly stability, during obstacle crossing. However, this strategy may be inefficient. Trailing toe clearance did not differ significantly between two groups. The results of this study suggest that children with DS tend to use inefficient and conservative strategies for obstacle crossing. Knowledge of both end-point and kinematic control of obstacle crossing in children with DS is useful for understanding the mechanisms of obstacle-related falls. Moreover, obstacle crossing can be used as a task-oriented rehabilitation program for children with DS.

  11. Break dance significantly increases static balance in 9 years-old soccer players.

    PubMed

    Ricotti, Leonardo; Ravaschio, Andrea

    2011-03-01

    Static balance in young athletes is an important ability that has a relevant influence on their present and future sport performances, as well as on the reduction in risk of injury. The present study reports data collected on three homogeneous groups of 9 years-old athletes (n=10 for each group), whose static balance was monitored every two months during an overall period of six months. At the beginning of the study, all of the children in each of the three groups were performing soccer activity with a frequency (three times a week) that was kept constant during the observation period. During the six months, group 1 maintained only the soccer activity, group 2 also performed swimming activity (twice a week) in parallel with the soccer activity, while group 3 started, at month 2, to perform soccer activity with a break dance course (twice a week). Double leg stance (with eyes open and closed) and single leg stance (on dominant and non-dominant leg) tests were performed using a force platform, and the COP area calculated for each trial. Results show a clear decrease in the "soccer+break dance" players COP area values during the six months, suggesting an improvement in their static balance. The difference was significantly greater with respect to that of soccer players and "soccer+swimming" players. This was evident in all the tests performed starting from two months after the break dance activity began.

  12. Portal hypertension: an uncommon clinical manifestation of Takayasu arteritis in a 9-year-old child

    PubMed Central

    Herrera, Cristina N; Tomala-Haz, Javier E

    2016-01-01

    Takayasu arteritis (TA) is the third most common childhood vasculitis and its clinical manifestations depend on the arteries involved. We report a case of a 9-year-old boy with multiple aneurysms in carotid and iliac arteries, subclavian and coronary arteries, and abdominal aorta. At the age of 7 years, he presented with recurrent fever and hepatosplenomegaly. An angio-computed tomography scan showed aneurysms in the left subclavian artery, abdominal aorta, and both proximal iliac arteries. He was diagnosed with TA and was treated with corticosteroids, aspirin, and enalapril. One year later, he was admitted to Dr Roberto Gilbert Children’s Hospital because of intracranial hemorrhage. Angiography revealed enlargement of aneurysms enlargement and new aneurysms. He also developed portal hypertension. Treatment with intravenous corticosteroids, azathioprine, and monthly intravenous cyclophosphamide was begun. After 6 months of no improvement, infliximab was begun. The aim of this article was to report the concurrence of coronary involvement and portal vein hypertension in pediatric TA because there were scarce reports on this matter. PMID:27895519

  13. Oral hygiene risk indicators among 6- to 9-year-old Taiwanese aboriginal children.

    PubMed

    Hsieh, Hui-Ju; Huang, Shun-Te; Tsai, Chi-Cheng; Chiou, Meng-Jao; Liao, Cheng-Ta

    2014-05-01

    This study investigated the dental health status, dietary habits, oral hygiene levels, and caretaker risk indicators among Taiwanese children. This cross-sectional purposive sampling study included 256 aboriginal children, 6 to 9 years old, living in remote regions in southern Taiwan. Participants received dental examinations, and questionnaires were completed by caretakers. Data were analyzed using the χ(2) test, t test, and multiple logistic regressions. The deft (sum of decayed, extracted, and filled primary teeth) and defs (sum of the decayed, extracted, and filled primary dentition surfaces) indices were affected by the frequencies of drinking sweetened beverages (P = .0006) and daily toothbrushing (P = .0032). Caretakers' toothbrushing frequency was a significant predictor of children's oral hygiene status (P < .0001). The odds ratio for children of caretakers with betel quid chewing habits having poor oral hygiene was 2.04 (P = .0184). Oral hygiene among aboriginal children in this study was inadequate. Caretakers' toothbrushing frequency and betel quid habit were significant predictors of poor children's oral hygiene.

  14. Long-Term Stability of Electroencephalographic Asymmetry and Power in 3 to 9 Year Old Children

    PubMed Central

    Vuga, Marike; Fox, Nathan A.; Cohn, Jeffrey F.; Kovacs, Maria; George, Charles J.

    2009-01-01

    We investigated test-retest stability of resting EEG asymmetry and power in the alpha frequency range across a 0.6 - to 3-year interval in 125 children (57 girls and 68 boys) for two age groups, 87 preschool children (3 to 5 year-olds) and 38 school-age children (6 to 9 year-olds). Children were from families with a parent’s history of unipolar or bipolar depression (36 girls and 43 boys) or control families with no parent history of depression nor any other psychiatric disorder (21 girls and 25 boys). Frontal EEG asymmetry stability was low to moderate; intraclass correlations ranged from zero to 0.48 in the eyes-open condition, and from 0.19 to 0.45 in the eyes-closed condition. Also, parietal EEG asymmetry was low to moderate; intraclass correlations ranged from 0.21 to 0.52 in the eyes-open condition and from 0.27 to 0.72 in the eyes-closed condition. Stability of EEG asymmetry was not related to age, sex of the child, or parent’s history of mood disorder. Frontal and parietal EEG power appeared moderately to highly stable. Intraclass correlations were between 0.65 and 0.86 in the eyes-open condition and between 0.52 and 0.90 in the eyes-closed condition. Although stability of EEG power was not statistical significantly different between preschool and school-age children, it consistently showed higher stability values in school-age children than in preschool children. Stability in school-aged children approached values as has been reported for adults. The findings provide partial support to the concept of frontal EEG asymmetry as a trait marker in childhood. PMID:18045715

  15. Interracial and Intra-Racial Stereotypes and Constructive Memory in 7- and 9-Year-Old African-American Children

    ERIC Educational Resources Information Center

    Williams, Tangela L.; Davidson, Denise

    2009-01-01

    Across several measures, the interracial and intra-racial views of 7- and 9-year-old African-American children were examined. Overall, children showed more negative views toward other African-Americans, labeling pictures of African-American children with more negative adjectives than pictures of European-American children. Children displayed more…

  16. Associations between perinatal factors and adiponectin and leptin in 9-year-old Mexican-American children

    PubMed Central

    Volberg, Vitaly; Harley, Kim G.; Aguilar, Raul S.; Rosas, Lisa G.; Huen, Karen; Yousefi, Paul; Davé, Veronica; Phan, Nguyet; Lustig, Robert H.; Eskenazi, Brenda; Holland, Nina

    2012-01-01

    Objectives To 1) determine whether perinatal factors (including maternal anthropometry and nutrition and early life growth measures) are associated with adiponectin and leptin levels in 9-year-old children, and 2) assess relationships between adiponectin, leptin and concurrent lipid profile in these children. Methods We measured plasma adiponectin and leptin for 146 mother - 9-year-old child pairs from the ongoing longitudinal birth cohort followed by the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS). Data on perinatal factors, including sociodemographics, maternal anthropometry and nutrition, and early life child growth were collected during pregnancy, birth and 6-month visits. Results Greater rate of weight and length gain during the first 6 months of life were associated with lower adiponectin in 9-year-olds (β=−2.0, P=0.04; β=−8.2, P=0.02, respectively) adjusting for child BMI. We found no associations between child adipokine levels and either maternal calorie, protein, total fat, saturated fat, fiber, sugar-sweetened beverage consumption during pregnancy or children’s concurrent sugar-sweetened beverage and fast food intake. Lipid profile in 9-year-old children closely reflected adiponectin but not leptin levels after adjustment for child BMI. Additionally, we report that child adipokine levels were closely related to their mothers’ levels at the 9-year-visit. Conclusion Overall, our results support the hypothesis that early life factors may contribute to altered adipokine levels in children. PMID:23325579

  17. Developing Access to Number Magnitude: A Study of the SNARC Effect in 7- to 9-Year-Olds

    ERIC Educational Resources Information Center

    van Galen, Mirte S.; Reitsma, Pieter

    2008-01-01

    The SNARC (spatial-numerical association of response codes) effect refers to the finding that small numbers facilitate left responses, whereas larger numbers facilitate right responses. The development of this spatial association was studied in 7-, 8-, and 9-year-olds, as well as in adults, using a task where number magnitude was essential to…

  18. High Antenatal Maternal Anxiety Is Related to ADHD Symptoms, Externalizing Problems, and Anxiety in 8- and 9-Year-Olds

    ERIC Educational Resources Information Center

    Van den Bergh, Bea R.H.; Marcoen, Alfons

    2004-01-01

    Associations between antenatal maternal anxiety, measured with the State Trait Anxiety Inventory, and disorders in 8- and 9-year-olds were studied prospectively in 71 normal mothers and their 72 firstborns. Clinical scales were completed by the mother, the child, the teacher, and an external observer. Hierarchical multiple regression analyses…

  19. Prevalence of molar incisor hypomineralization in 7–9-year-old children of Bengaluru City, India

    PubMed Central

    Subramaniam, Priya; Gupta, Tulika; Sharma, Akhilesh

    2016-01-01

    Background: Molar incisor hypomineralization (MIH) is a developmental defect. The prevalence of MIH ranges widely from 2.4% to 40.2%. Aim: This study was under taken to determine the prevalence of MIH in 7–9-year-old children of Bengaluru City, India. Materials and Methods: A cross-sectional epidemiological study was conducted in a representative sample of 2500 school children aged 7–9 years of Bengaluru, India. Oral examination was carried out by a single trained calibrated examiner under natural daylight. Results: Twelve children (0.48%) were diagnosed with MIH. A total of 68 teeth were observed with MIH. All four first permanent molars were affected in 50% of children. In the molar group, mandibular molars (29.41%) were more frequently affected than maxillary molars (27.94%). Conclusion: The prevalence of MIH in 7–9-year-old children of Bengaluru was 0.48%, with no gender predilection. PMID:27041893

  20. Treatment of a TIPS-Biliary Fistula by Stent-Graft in a 9-Year-Old Boy

    SciTech Connect

    Boyvat, Fatih; Cekirge, Saruhan; Balkanci, Ferhun; Besim, Aytekin

    1999-01-15

    We report a 9-year-old male cirrhotic patient with acute occlusion of a transjugular intrahepatic portosystemic shunt (TIPS) due to a biliary-to-TIPS fistula which occurred 9 hr after the TIPS procedure. Immediate TIPS revision was performed and the fistula was treated by placement of an endoluminal stent-graft. At 12-month follow-up color Doppler examination demonstrated a patent shunt.

  1. Primary Lymphangioma of the Palatine Tonsil in a 9-Year-Old Boy: A Case Presentation and Literature Review

    PubMed Central

    Iliadou, Eleftheria; Papapetropoulos, Nektarios; Karamatzanis, Eleftherios; Saravakos, Konstantinos

    2016-01-01

    Primary lymphangiomas or lymphangiomatous polyps of the palatine tonsil are rare benign lesions that are described infrequently in the literature. The majority of the published cases concern adults. We report a case of a lymphangiomatous lesion of the right palatine tonsil of a 9-year-old boy. Our clinical suspicion was confirmed by the histological examination after tonsillectomy and the diagnosis of primary lymphangioma of the tonsil was made. In this case we discuss the clinical and histopathological features of this lesion and present a short review of the current literature. PMID:27872780

  2. Gorham-Stout disease presenting with dyspnea and bone pain in a 9-year-old girl.

    PubMed

    Davalos, Eric A; Gandhi, Nishant M; Barank, David; Varma, Rajeev K

    2015-01-01

    Gorham-Stout (GS) disease is a rare bone disorder of unknown etiology that is characterized by local proliferation of small vascular or lymphatic channels, resulting in progressive osteolysis and bone resorption. The diagnosis of GS disease is one of exclusion, with radiography and histopathology playing key roles. We describe a 9-year-old girl who presented to us with dyspnea and bone pain. She was found to have a cystic mass of the upper extremity, multiple cystic bone lesions, multiple fractures of different ages, and pleural effusions. We review the radiologic images that helped establish the diagnosis of GS disease.

  3. Surgical treatment of cervical unilateral locked facet in a 9-year-old boy: A case report

    PubMed Central

    Cobanoglu, Mutlu; Enercan, Meric; Yilar, Sinan; Hamzaoglu, Azmi

    2015-01-01

    Most of the cervical spine injuries in the pediatric population are typically seen in the upper cervical region. Unilateral cervical facet dislocation (UFD) in subaxial region is a rare injury in pediatric population. In this paper, a rare case of delayed locked UFD in a 9-year-old boy with rare injury mechanism treated surgically is reported. Clinical and radiological findings were described. The patient with C6-7 UFD without neurologic deficit was underwent open reduction and internal fixation via anterior and posterior combined approaches. Significant improvement of pain and free motion in cervical spine was obtained. There was no complication during the follow up. Only three case reports presented about the lower cervical spine injury with UFD under the age of 10 were found in the literature. PMID:25788821

  4. Logistics of using the Actiheart physical activity monitors in urban Mexico among 7- to 9-year-old children.

    PubMed

    Wilson, Hannah; Dickinson, Federico; Griffiths, Paula; Bogin, Barry; Varela-Silva, Maria Inês

    2011-01-01

    Logistics of using new measurement devices are important to understand when developing protocols. This paper discusses the logistics of using Actiheart physical activity monitors on children in an urban, tropical environment in a developing country. Actiheart monitoring of 36 children aged 7-9 years old was undertaken for 7 days in the city of Mérida, Yucatán, Mexico. The Actiheart proved fragile for children and difficult to mend in the field. The excessive sweating due to the tropical climate caused poor adherence of the electrode pads, requiring a pad change midway through and extra pads to be provided. Also extra time was needed to be allotted for increased instructions to participants and their mothers and for individual calibration. When collecting objectively measured physical activity data under harsh conditions, the protocol must accommodate local conditions and device limitations and allow increased time with participants to obtain good quality data.

  5. Long-term outcome of peroral endoscopic myotomy for achalasia treatment in a 9-year-old female patient.

    PubMed

    Yamashita, Kanefumi; Shiwaku, Hironari; Hirose, Ryuichiro; Kai, Hiroki; Nakashima, Ryo; Kato, Daisuke; Beppu, Richiko; Takeno, Shinsuke; Sasaki, Takamitsu; Nimura, Satoshi; Iwasaki, Akinori; Inoue, Haruhiro; Yamashita, Yuichi

    2016-11-01

    Achalasia is a primary motility disorder with incomplete lower esophageal sphincter relaxation; it has an annual incidence of 0.11 cases per 100 000 children. Peroral endoscopic myotomy (POEM) is a new endoscopic treatment method for achalasia. Reports about POEM in pediatric patients are rare. We herein report the case of a 9-year-old female patient with achalasia who underwent POEM. The patient underwent endoscopic balloon dilatation because medication was not effective at a previous hospital; however, endoscopic balloon dilatation was not effective either. She then underwent successful POEM upon admission at our hospital. The patient was symptom-free at 2 years postoperatively with no signs of esophagitis in the absence of proton-pump inhibitor therapy.

  6. Virilizing adrenal oncocytoma in a 9-year-old girl: rare neoplasm with an intriguing postoperative course.

    PubMed

    Yordanova, Galina; Iotova, Violeta; Kalchev, Kalin; Ivanov, Krasimir; Balev, Boyan; Kolev, Nikola; Tonev, Anton; Oosterhuis, Wolter

    2015-05-01

    Adrenal oncocytoma is an extremely rare neoplasm, which is mostly non-functional. Only five cases of childhood adrenal oncocytoma have been described so far, all of which were hormonally active. Currently, guidelines for management and follow-up are not available. We report a 9-year-old girl with benign adrenal oncocytoma, presenting with severe short-term virilization. After diagnostic work-up the patient underwent laparoscopic unilateral adrenalectomy. For the first 2 weeks following surgery she suffered marked mood swings, irritability and fatigue. There were no other clinical and/or laboratory abnormalities except the rapid drop-down of androgen levels to normal values. Follow-up showed no signs of recurrence and in the absence of signs of adrenal insufficiency, we speculate that, the rapid drop of androgen levels after removal of the tumor might be the reason for the deteriorated psychoemotional condition of our patient.

  7. Feature versus gestalt representation of stimuli in the mismatch negativity system of 7- to 9-year-old children.

    PubMed

    Molholm, Sophie; Gomes, Hilary; Lobosco, Jacqueline; Deacon, Diana; Ritter, Walter

    2004-05-01

    We examined preattentive auditory change detection in 7- to 9-year-old children. The question of interest was whether the preattentive comparison of stimuli indexed by the scalp-recorded mismatch negativity (MMN) was performed on representations of individual stimulus features or on gestalt representations of their combined attributes. The design of the study, based on a work by D. Deacon, J. Nousak, M. Pilotti, W. Ritter, and C. Yang (Psychophysiology, 1998), was such that both feature and gestalt representations could have been available to the comparator mechanism generating the MMN. The data indicated that for the majority of the children-those that exhibited an inverse relationship between the amplitude of the MMN and the probability of the deviant-the MMN was based on feature-specific information. This study also provides a method to obtain MMNs to deviants in three different features in the time usually required to obtain an MMN to a single acoustic feature.

  8. Severe constrictive pericarditis after parvovirus B19 and human herpes virus 6 infection in a 9-year-old girl.

    PubMed

    Backhoff, David; Steinmetz, Michael; Ruschewski, Wolfgang; Stastny, Barbara; Kandolf, Reinhard; Krause, Ulrich

    2013-01-01

    We report on a 9-year-old girl who developed signs of congestive heart failure with significant ascites due to constrictive pericarditis. Cardiac catheterization was performed to establish the diagnosis and to rule out restrictive cardiomyopathy. Endomyocardial biopsies were positive for activated macrophages and small-vessel disease, but no viral genomes were detected. Open pericardectomy was performed and histopathologic examination of the resected thickened pericardium showed extensive fibrosis and hyaline degeneration. A combined infection with parvovirus B19 (PVB19) and human herpes virus 6 (HHV6; subtype B) was proven within the resected pericardium. We suggest that local HHV6-induced immunosuppression enhanced the PVB19 infection, thus resulting in chronic infection and leading to constrictive pericarditis.

  9. Emerging Behavioral Flexibility in Loop Writing: A longitudinal study in 7- to 9-Year-Old Primary School Children.

    PubMed

    Bosga-Stork, Ida M; Bosga, Jurjen; Meulenbroek, Ruud G J

    2017-04-01

    The development of the ability to adapt one's motor performance to the constraints of a movement task was examined in a longitudinal study involving 7 to-9-year-old children who were asked to perform a preparatory handwriting task. The capacity for sensorimotor synchronization was captured by the standard deviation of the relative phase between pacing signals and writing movements and the capacity to adjust wrist-finger coordination while performing repetitive movements was analyzed by autocorrelations of the vertical pen-tip displacements. While the capacity for synchronization improved with age, the autocorrelations were positive at short time lags only and hardly changed with age. A measure of "the long-term memory" of time series (Hurst exponent) confirmed that the findings were systematic rather than noise. Collectively, the results indicate that flexible movement strategies emerge early on in the first 3 years of formal handwriting education. Implications for educational and clinical practice are considered.

  10. When Stroop helps Piaget: An inter-task positive priming paradigm in 9-year-old children.

    PubMed

    Linzarini, A; Houdé, O; Borst, G

    2015-11-01

    To determine whether inhibitory control is domain general or domain specific in school children, we asked 40 9-year-old children to perform an inter-task priming paradigm in which they responded to Stroop items on the primes and to Piaget number conservation items on the probes. The children were more efficient in the inhibition of a misleading "length-equals-number" heuristic in the number conservation task if they had successfully inhibited a previous prepotent reading response in the Stroop task. This study provides evidence that the inhibitory control ability of school children generalizes to distinct cognitive domains, that is, verbal for the Stroop task and logico-mathematical for Piaget's number conservation task.

  11. Changes in Caries Risk and Activity of a 9-Year-Old Patient with Niemann-Pick Disease Type C

    PubMed Central

    Mesquita-Guimarães, Késsia Suênia Fidelis; De Rossi, Andiara; Freitas, Aldevina Campos; Nelson-Filho, Paulo; da Silva, Raquel Assed; de Queiroz, Alexandra Mussolino

    2015-01-01

    Objective. This case report describes the changes in caries risk and activity and dental treatment of a 9-year-old patient who presented with signs and symptoms of Niemann-Pick disease type C (NPC). Treatment. The preventive dental treatment included instructions to caregivers for oral hygiene and diet. A calcium hydroxide pulpotomy and restorative dental treatments were performed in a dental office with desensitization techniques and behavioral management. The patient was attended every 3 months for the control of dental plaque biofilm, for topical fluoride application, and for observing the pulpotomized tooth. Results. The bacterial plaque biofilm was being adequately controlled by the caregiver. After 2 years, the clinical and radiographic examination of the pulpotomized tooth showed the absence of internal root resorption and bone rarefaction, and clinical examination showed tooth sensitivity, dental pain, and gingival swelling. Conclusion. The pulpotomy prevented clinical and radiographic success. Dentists must be aware of and be able to identify systemic and local aspects associated with caries risk of children with NPC disease. Furthermore, dentists must employ stringent preventive measures and provide instructions to caregivers to reduce caries risk. PMID:25685563

  12. Transversal dental arch dimensions in 9-year-old children born in the 1960s and the 1980s.

    PubMed

    Lindsten, R; Ogaard, B; Larsson, E

    2001-12-01

    The transversal arch dimension has been studied in 2 different cohorts of 9-year-old children, a group of 119 (56 girls and 63 boys) from Norway and a group of 133 (72 girls and 61 boys) from Sweden. Half of the children in each group were born in the 1960s and half in the 1980s. The maxillary and mandibular transversal dimensions did not differ between the 1960s groups and the 1980s groups when the maxilla and the mandible were studied separately. When the intermaxillary relationship was assessed, a significant reduction in the intermaxillary difference was found in the boys born in the 1980s compared with the boys born in the 1960s. This was confirmed with different measurement points. In the girls, the mesial drift of the first permanent molars, because of a greater prevalence of caries in the 1960s groups, masked this effect. When the mesial drift of the first permanent molars in the girls born in the 1960s was considered, the transversal intermaxillary difference showed the same secular pattern as in the boys. When the mesial drift of the first permanent molars was considered, the intermaxillary difference in the 1960s groups resembled that found in an American sample of northwest European ancestry born in the 1940s to a greater extent compared with the children born in the 1980s.

  13. A Case of Pulmonary Paragonimiasis with Involvement of the Abdominal Muscle in a 9-Year-Old Girl

    PubMed Central

    Cho, Ah-Rum; Lee, Hae-Ran; Lee, Kwan-Sub; Lee, Sang-Eun

    2011-01-01

    In Korea, many people enjoy eating raw or underkooked freshwater crayfish and crabs which unfortunately may cause paragonimiasis. Here, we describe a case of pulmonary and abdominal paragonimiasis in a 9-year-old girl, who presented with a 1-month history of abdominal pain, especially in the right flank and the right inguinal area, with anorexia. A chest radiograph revealed pleural effusion in both lungs, and her abdominal sonography indicated an inflammatory lesion in the right psoas muscle. Peripheral blood analysis of the patient showed hypereosinophilia (66.0%) and an elevated total serum IgE level (>2,500 IU/ml). The pleural effusion tested by ELISA were also positive for antibodies against paragonimiasis. Her dietary history stated that she had ingested raw freshwater crab, 4 months previously. The diagnosis was pulmonary paragonimiasis accompanied by abdominal muscle involvement. She was improved after 5 cycles of praziquantel treatment and 2 times of pleural effusion drainage. In conclusion, herein, we report a case of pulmonary and abdominal paragonimiasis in a girl who presented with abdominal pain and tenderness in the inguinal area. PMID:22355209

  14. Association between body composition and blood pressure in a contemporary cohort of 9-year-old children.

    PubMed

    Brion, M A; Ness, A R; Davey Smith, G; Leary, S D

    2007-04-01

    Elevated blood pressure (BP) in children is an early risk factor for cardiovascular disease and is positively associated with body mass index (BMI). However, BMI does not distinguish between fat and lean masses, and the relationship of BP in children to different elements of body composition is not well established. BP, BMI and body composition were measured in 6863 children enrolled in the Avon Longitudinal Study of Parents and Children. Fat mass, lean mass and trunk fat were assessed using dual-energy X-ray absorptiometry. After full adjustment for confounders, total body fat and BMI were positively associated with systolic blood pressure (SBP) (beta=3.29, 95% confidence interval CI 3.02, 3.57 mm Hg/standard deviation (s.d.) and beta=3.97, 95% CI 3.73, 4.21 mm Hg/s.d., respectively) and diastolic blood pressure (DBP) (beta=1.26, 95% CI 1.05, 1.46 mm Hg/s.d. and beta=1.37, 95% CI 1.19, 1.54 mm Hg/s.d., respectively). SBP was also positively associated with lean mass (beta=3.38, 95% CI 2.95, 3.81 mm Hg/s.d.), and weakly associated with trunk fat (beta=1.42, 95% CI -0.06, 2.90 mm Hg/s.d., independent of total fat mass), which was robust in girls only. The association between lean mass and SBP remained even after accounting for fat mass. SBP in 9-year-old children is independently associated with fat mass and lean mass and, to a lesser extent, trunk fat in girls. In this analysis, because both fat and lean masses are associated with BP, BMI predicts BP at least as well as these components of body composition.

  15. Interrelationships among Age, Sex, and Depth of Sport Experience on a Complex Motor Task by 4- to 9-Year Old Children.

    ERIC Educational Resources Information Center

    Kuhlman, Jolynn S.; Beitel, Patricia A.

    Age, gender, and/or previous experience seem to be related to the performance/learning of new perceptual motor tasks. This study sought to determine the relative interrelationships of age, gender, and the depth of sport experience on initial practice of a complex perceptual motor soccer task for 46 children 4- to 9-years-old who were enrolled in a…

  16. So Young and Already Victims of Stereotype Threat: Socio-Economic Status and Performance of 6 to 9 Years Old Children on Raven's Progressive Matrices

    ERIC Educational Resources Information Center

    Desert, Michel; Preaux, Marie; Jund, Robin

    2009-01-01

    The aim of this study was to verify whether children from low socio-economic status (SES) are victims of stereotype threat. Children in first grade (6 to 7 years old) and third grade (8 to 9 years old) performed Raven's progressive matrices, an intellectual ability test commonly used by psychologists. The test was presented either with the…

  17. Locally Advanced Stage High-Grade Mucoepidermoid Carcinoma of Salivary Gland in a 9-Year-Old Girl: The Controversy of Adjuvant Therapy.

    PubMed

    Martínez, Olga Micol; Dorado, Elena Daghoum; García, María Dolores Amorós; Ramírez, María Isabel Oviedo; de la Fuente Muñoz, Isabel; Soler, Jose Luis Fuster

    2016-09-05

    Malignant salivary gland tumors are rare in children, mostly represented by low-grade mucoepidermoid carcinomas. For these patients, long-term survival rates above 95% are reported after surgical resection. Here we report a case of a 9-year-old girl with a high grade locally advanced mucoepidermoid carcinoma undergoing adjuvant radiotherapy and chemotherapy after surgery. We emphasize the controversy and lack of evidence-based indication for these highly toxic adjuvant therapy modalities in children.

  18. Locally Advanced Stage High-Grade Mucoepidermoid Carcinoma of Salivary Gland in a 9-Year-Old Girl: The Controversy of Adjuvant Therapy

    PubMed Central

    Martínez, Olga Micol; Dorado, Elena Daghoum; García, María Dolores Amorós; Ramírez, María Isabel Oviedo; de la Fuente Muñoz, Isabel; Soler, Jose Luis Fuster

    2016-01-01

    Malignant salivary gland tumors are rare in children, mostly represented by low-grade mucoepidermoid carcinomas. For these patients, long-term survival rates above 95% are reported after surgical resection. Here we report a case of a 9-year-old girl with a high grade locally advanced mucoepidermoid carcinoma undergoing adjuvant radiotherapy and chemotherapy after surgery. We emphasize the controversy and lack of evidence-based indication for these highly toxic adjuvant therapy modalities in children. PMID:27746885

  19. Little girls in a grown up world: Exposure to sexualized media, internalization of sexualization messages, and body image in 6-9 year-old girls.

    PubMed

    Slater, Amy; Tiggemann, Marika

    2016-09-01

    Despite widespread public concern about the early sexualization of young girls, as yet there has been little empirical examination of potential negative effects. In the present study a sample of 300 6-9 year-old girls completed individual interviews assessing exposure to sexualized media, internalization of sexualized messages (measured via preference for sexualized clothing), and body image attitudes (body esteem, body dissatisfaction). Exposure to sexualized media was found to be correlated with internalization of sexualization messages, itself correlated with negative body image. The findings provide preliminary evidence that sexualized messages appear to be internalized by very young girls which, in turn, has negative implications for how they feel about their bodies.

  20. A disseminated alveolar rhabdomyosarcoma in a 9-year-old boy disclosed by chromosomal translocation (2;13) (q35;q14)

    PubMed

    Brichard, B; Ninane, J; Gosseye, S; Verellen-Dumoulin, C; Vermylen, C; Rodhain, J; Cornu, G

    1991-01-01

    A 9-year-old boy presented with a small subcutaneous tumor of the trunk and diffuse bone marrow involvement. The first histological diagnosis given was undifferentiated malignancy possibly of neural crest origin and chemotherapy was started immediately using vincristine, cyclophosphamide, cisplatin, and teniposide (OPEC). Complete response was achieved after four courses of chemotherapy. Histological slides were then reviewed and the final diagnosis of alveolar rhabdomyosarcoma (RMS) was retained. Moreover, chromosome analysis of malignant cells in the bone marrow revealed a translocation involving chromosomes 2 and 13:t(2;13) (q35;q14). This specific karyotype finding has been recently reported in a few cases and could be specific for alveolar RMS. The patient had a relapse 7 months after diagnosis and died 4 months later.

  1. Hepatosplenic gamma/delta T-cell lymphoma with isochromosome 7q, translocation t(7;21), and tetrasomy 8 in a 9-year-old girl.

    PubMed

    Rossbach, Hans-Christoph; Chamizo, Wilfredo; Dumont, Doris P; Barbosa, Jerry L; Sutcliffe, Maxine J

    2002-02-01

    The authors report a child younger than age 15 years with a rare hepatosplenic gamma/delta T-cell lymphoma, which is highly aggressive and primarily seen in young men. A 9-year-old girl presented with thrombocytopenia and hepatosplenomegaly. Bone marrow analysis revealed a metastatic pleomorphic lymphoma of peripheral T-cell phenotype, with rearrangement of the T-cell receptor gamma/delta and expression of CD3 and CD16/56. Instead of the previously reported primary, nonrandom, chromosomal abnormalities, isochromosome 7q and trisomy 8, this patient had four copies each of chromosome 7q, including isochromosome 7[i(7)(q10)] and der(21)t(7;21), as well as chromosome 8. This entity needs to be considered in women and children with lymphoma. Conventional therapy appears to be inadequate for cure.

  2. Aerobic fitness testing in 6- to 9-year-old children: reliability and validity of a modified Yo-Yo IR1 test and the Andersen test.

    PubMed

    Ahler, T; Bendiksen, M; Krustrup, P; Wedderkopp, N

    2012-03-01

    This study analysed the reliability and validity of two intermittent running tests (the Yo-Yo IR1 test and the Andersen test) as tools for estimating VO(2max) in children under the age of 10. Two groups, aged 6-7 years (grade 0, n = 18) and 8-9 years (grade 2, n = 16), carried out two repetitions of a modified Yo-Yo IR1 test (2 × 16 m) and the Andersen test, as well as an incremental treadmill test, to directly determine the VO(2max). No significant differences were observed in test-retest performance of the Yo-Yo IR1 test [693 ± 418 (±SD) and 670 ± 328 m, r (2) = 0.79, CV = 19%, p > 0.05, n = 32) and the Andersen test (988 ± 77 and 989 ± 87 m, r (2) = 0.86, CV = 3%, p > 0.05, n = 31). The Yo-Yo IR1 (r (2) = 0.47, n = 31, p < 0.002) and Andersen test performance (r (2) = 0.53, n = 32, p < 0.001) correlated with the VO(2max). Yo-Yo IR1 performance correlated with Andersen test performance (r (2) = 0.74, n = 32, p < 0.0001). In conclusion, the Yo-Yo IR1 and the Andersen tests are reproducible and can be used as an indicator of aerobic fitness for 6- to 9-year-old children.

  3. How to Measure Qualitative Understanding of DC-Circuit Phenomena - Taking a Closer Look at the External Representations of 9-Year-Olds

    NASA Astrophysics Data System (ADS)

    Kallunki, Veera

    2013-04-01

    Pupils' qualitative understanding of DC-circuit phenomena is reported to be weak. In numerous research reports lists of problems in understanding the functioning of simple DC-circuits have been presented. So-called mental model surveys have uncovered difficulties in different age groups, and in different phases of instruction. In this study, the concept of qualitative understanding, and the content or position of reported mental models of DC-circuit phenomena are discussed. On the grounds of this review, new tools for investigating qualitative understanding and analysing external representations of DC-circuit phenomena are presented. According to this approach, the external representations of DC-circuit phenomena that describe pupils' expressed conceptions of the topic should include both empirical-based models and theoretical explanations. In the empirical part of this study , third-graders (9-year-olds) learning DC-circuit phenomena in a comprehensive school in a small group were scrutinised. The focus of the study is the external representations manifested in the talk of the small group. The study challenges earlier studies, which claim that children exhibit a wide range of qualitative difficulties when learning DC-circuit phenomena. In this study it will be shown that even in the case of abstract subject matter like DC-circuit phenomena, small groups that highlight empirical-based modelling and activate talk can be a fruitful learning environment, where pupils' qualitative understanding really develops. Thus, the study proposes taking a closer look at pupils' external representations concerning DC-circuit phenomena.

  4. A 9-Year-Old-Girl with Phelan McDermid Syndrome, Who Had been Diagnosed with an Autism Spectrum Disorder

    PubMed Central

    Görker, I; Gürkan, H; Demir Ulusal, S; Atlı, E; Ikbal Atlı, E

    2016-01-01

    Abstract Phelan McDermid Syndrome (PHMDS) (OMIM #606232), is a contiguous gene disorder resulting from deletion of the distal long arm of chromosome 22. The 22q13.3 deletions and mutations that lead to a loss of a functional copy of SHANK3 (OMIM *606230) cause the syndrome, characterized by moderate to profound intellectual disability, severely delayed or absent speech, hypotonia, and autism spectrum disorder (ASD) or ASD traits. In this study, we present the case of a 9-year-old girl who had earlier been diagnosed with an ASD. Our findings were a clinically mild intellectual disability, rounded face, pointed chin but no autistic findings. We learned that her neuromotor development was delayed and she had neonatal hypotonia in her history. A heterozygous deletion of MLC1, SBF1, MAPK8IP2, ARSA, SHANK3 and ACR genes, located on 22q13.33, was defined by multiplex ligation-dependent probe amplification (MLPA). Deletion of 22q13.3 (ARSA) region was confirmed by a fluorescent in situ hybridization (FISH) technique. The 22q13.3 deletion was found to be de novo in our patient, and she was diagnosed with PHMDS. We confirmed the 22q13.3 deletion and also determined a gain of 8p23.3-23.2 by array comparative genomic hybridization (aCGH). Fluorescent in situ hybridization was performed to determine whether the deletion was of parental origin and to identify regions of chromosomes where the extra 8p may have been located. The parents were found to be normal. The extra copy of 8p was observed on 22q in the patient. She is the first case reported in association with the 22q deletion of 8p duplications in the literature. PMID:28289594

  5. A cluster-randomized controlled trial to reduce sedentary behavior and promote physical activity and health of 8-9 year olds: The Transform-Us! Study

    PubMed Central

    2011-01-01

    Background Physical activity (PA) is associated with positive cardio-metabolic health and emerging evidence suggests sedentary behavior (SB) may be detrimental to children's health independent of PA. The primary aim of the Transform-Us! study is to determine whether an 18-month, behavioral and environmental intervention in the school and family settings results in higher levels of PA and lower rates of SB among 8-9 year old children compared with usual practice (post-intervention and 12-months follow-up). The secondary aims are to determine the independent and combined effects of PA and SB on children's cardio-metabolic health risk factors; identify the factors that mediate the success of the intervention; and determine whether the intervention is cost-effective. Methods/design A four-arm cluster-randomized controlled trial (RCT) with a 2 × 2 factorial design, with schools as the unit of randomization. Twenty schools will be allocated to one of four intervention groups, sedentary behavior (SB-I), physical activity (PA-I), combined SB and PA (SB+PA-I) or current practice control (C), which will be evaluated among approximately 600 children aged 8-9 years in school year 3 living in Melbourne, Australia. All children in year 3 at intervention schools in 2010 (8-9 years) will receive the intervention over an 18-month period with a maintenance 'booster' delivered in 2012 and children at all schools will be invited to participate in the evaluation assessments. To maximize the sample and to capture new students arriving at intervention and control schools, recruitment will be on-going up to the post-intervention time point. Primary outcomes are time spent sitting and in PA assessed via accelerometers and inclinometers and survey. Discussion To our knowledge, Transform-Us! is the first RCT to examine the effectiveness of intervention strategies for reducing children's overall sedentary time, promoting PA and optimizing health outcomes. The integration of consistent

  6. Mathematical Modelling with 9-Year-Olds

    ERIC Educational Resources Information Center

    English, Lyn D.; Watters, James J.

    2005-01-01

    This paper reports on the mathematical modelling of four classes of 4th-grade children as they worked on a modelling problem involving the selection of an Australian swimming team for the 2004 Olympics. The problem was implemented during the second year of the children's participation in a 3-year longitudinal program of modelling experiences…

  7. Effect of implant design on knee flexion.

    PubMed

    Dennis, Douglas A; Heekin, R David; Clark, Charles R; Murphy, Jeffrey A; O'Dell, Tammy L; Dwyer, Kimberly A

    2013-03-01

    From March 2006 to August 2008, 93 subjects (186 knees) underwent simultaneous bilateral total knee arthroplasty performed by eight surgeons at North American centers. This randomized study was conducted to determine whether non-weight-bearing passive flexion was superior for knees receiving a posterior stabilized high flexion device compared to a posterior stabilized standard device in the contra-lateral knee. Weight-bearing single leg active flexion was one secondary endpoint. Follow-up compliance was 92.5%. Results show small, but significant superiority in the motion metrics for the high flexion device compared to the standard device 12 months after surgery, especially for a subgroup of patients with pre-operative flexion less than 120° in both knees. Thus, the ideal candidate for the high flexion device may be one with lesser pre-operative flexion.

  8. Development of a knee joint motion simulator to evaluate deep knee flexion of artificial knee joints.

    PubMed

    Takano, Y; Ueno, M; Kiguchi, K; Ito, J; Mawatari, M; Hotokebuchi, T

    2008-01-01

    A purpose of this study is to examine the effect that quadriceps femoris force gives to rotation angle and joint reaction force of total knee prosthesis during deep knee flexion such as a unique sitting style called 'seiza' in Japanese. For the evaluation, we developed the knee motion simulator which could bend to 180 degrees continually simulating the passive flexion performed by clinicians. A total knee prosthesis, which is a specially-devised posterior stabilized type and capable of flexion up to 180 degrees, was inserted into bone model. And this prosthesis pulled by three kinds of quadriceps femoris forces to perform parameter study. The results obtained in this study were showed the same tendency with those in the past cadaveric experiment. It is suggested that the rotation angle and joint reaction force of total knee prosthesis are affected by shape of prosthesis, a vector of quadriceps femoris force, and bony aliments during deep knee flexion.

  9. In vivo knee kinematics during stair and deep flexion activities in patients with bicruciate substituting total knee arthroplasty.

    PubMed

    Kuroyanagi, Yuji; Mu, Shang; Hamai, Satoshi; Robb, William J; Banks, Scott A

    2012-01-01

    Orthopedic surgeons and their patients continue to seek better functional outcomes after total knee arthroplasty. The bicruciate substituting (BCS) total knee arthroplasty design has been introduced to achieve more natural knee mechanics. The purpose of this study was to characterize kinematics in knees with BCS arthroplasty during deep flexion and stair activities using fluoroscopy and model-image registration. In 20 patients with 25 BCS knees, we observed average implant flexion of 128° during kneeling and consistent posterior condylar translations with knee flexion. Tibial rotations were qualitatively similar to those observed in the arthritic natural knee. Knee kinematics with BCS arthroplasty were qualitatively more similar to arthritic natural knees than knees with either posterior cruciate-retaining or posterior-stabilized arthroplasty.

  10. Assessment of reactive synovitis in rotating-platform posterior-stabilized design: a 10-year prospective matched-pair MRI study.

    PubMed

    Meftah, Morteza; Potter, Hollis G; Gold, Stephanie; Ranawat, Anil S; Ranawat, Amar S; Ranawat, Chitranjan S

    2013-10-01

    This is the first long-term (mean 11.6 years), prospective, matched-pair study (based on age, gender, BMI and UCLA scores) using MAVRIC (multi-acquisition variable-resonance image combination) magnetic resonance imaging to analyze reactive synovitis and osteolysis between rotating-platform posterior-stabilized (RP-PS), fixed-bearing metal-back (FB-MB), and all-polyethylene tibial (APT) in active patients (24 total, 8 in each group, mean age of 64 years, mean UCLA of 8.5) with identical femoral component and polyethylene. Reactive synovitis was observed in 6 RP-PS (75%), all 8 FB-MB (100%), and 6 APT (75%). There was a significant difference between the RP-PS and FB-MB knees in volumetric synovitis (P=0.023). Osteolysis with bone loss more than 4mm was seen in 3 FB-MB, 2 APT and none for RP-PS. These were not statistically significant.

  11. Science Activities for Children 3 to 9 Years Old.

    ERIC Educational Resources Information Center

    Nelson, Bonnie E.

    Activities in the life and physical sciences are provided (in separate sections) for preschool and elementary school students. Life science activities include those related to plants, soil, habitats, fossils, animals, life cycles, food chains, nutrition, and other biologically-oriented topics. Physical science activities include those related to…

  12. Condylar-stabilizing tibial inserts do not restore anteroposterior stability after total knee arthroplasty.

    PubMed

    Sur, Yoo-Joon; Koh, In-Jun; Park, Se-Wook; Kim, Hyung-Jin; In, Yong

    2015-04-01

    The Triathlon condylar-stabilizing (CS) lipped insert is designed to provide anteroposterior (AP) stability of the posterior-stabilized (PS) insert, without a post. The purpose of this study was to compare the AP stability of the knee in patients with Triathlon CS and PS total knee arthroplasty (TKA) with midterm follow-up. Thirty-one patients received a Triathlon PS TKA in one knee and a Triathlon CS TKA in the contralateral knee, and 28 patients were followed up with a minimum duration of 5years. Although there was no difference in functional outcomes, the posterior displacement was significantly greater in the CS TKA group than in the PS TKA group (P<0.001). The Triathlon CS lipped insert could not restore posterior stability with PCL sacrifice.

  13. Total knee arthroplasty in patients with a previous patellectomy.

    PubMed

    Maslow, Jed; Zuckerman, Joseph D; Immerman, Igor

    2013-01-01

    Post-patellectomy patients represent a specific subgroup of patients that may develop arthritis and persistent knee pain and potentially require treatment with total knee arthroplasty. This article reviews the treatment and functional outcomes following total knee arthroplasty in patients with prior patellectomy. A case report is presented as an example of the clinical management of a post-patellectomy patient with significant knee pain and disability treated with total knee arthroplasty. Emphasis will be placed in decision- making, specifically with the use of a posterior stabilized implant. In addition, postoperative strengthening of the quadriceps is essential to compensate for the lack of the patella and increase the success of total knee arthroplasty in this subgroup of patients.

  14. Runner's Knee

    MedlinePlus

    ... Surgery? A Week of Healthy Breakfasts Shyness Runner's Knee KidsHealth > For Teens > Runner's Knee A A A ... told he had runner's knee. What Is Runner's Knee? Runner's knee is the term doctors use for ...

  15. Knee pain

    MedlinePlus

    Pain - knee ... Knee pain can have different causes. Being overweight puts you at greater risk for knee problems. Overusing your knee can trigger knee problems that cause pain. If you have a history of arthritis, it ...

  16. Tibiofemoral force following total knee arthroplasty: comparison of four prosthesis designs in vitro.

    PubMed

    Nicholls, Rochelle L; Schirm, Andreas C; Jeffcote, Benjamin O; Kuster, Markus S

    2007-11-01

    Despite ongoing evolution in total knee arthroplasty (TKA) prosthesis design, restricted flexion continues to be common postoperatively. Compressive tibiofemoral force during flexion is generated through the interaction between soft tissues and prosthesis geometry. In this study, we compared the compressive tibiofemoral force in vitro of four commonly used prostheses: fixed-bearing PCL (posterior cruciate ligament)-retaining (PFC), mobile-bearing posterior-stabilized (PS), posterior-stabilized with a High Flex femoral component (HF), and mobile-bearing PCL-sacrificing (LCS). Fourteen fresh-frozen cadaver knee joints were tested in a passive motion rig, and tibiofemoral force measured using a modified tibial baseplate instrumented with six load cells. The implants without posterior stabilization displayed an exponential increase in force after 90 degrees of flexion, while PS implants maintained low force throughout the range of motion. The fixed-bearing PFC prosthesis displayed the highest peak force (214 +/- 68 N at 150 degrees flexion). Sacrifice of the PCL decreased the peak force to a level comparable with the LCS implant. The use of a PCL-substituting post and cam system reduced the peak force up to 78%, irrespective of whether it was a high-flex or a standard PS knee. However, other factors such as preoperative range of motion, knee joint kinematics, soft tissue impingement, and implantation technique play a role in postoperative knee function. The present study suggests that a posterior-stabilized TKA design might be advantageous in reducing soft tissue tension in deep flexion. Further research is necessary to fully understand all factors affecting knee flexion after TKA.

  17. Design and cadaveric validation of a novel device to quantify knee stability during total knee arthroplasty.

    PubMed

    Siston, Robert A; Maack, Thomas L; Hutter, Erin E; Beal, Matthew D; Chaudhari, Ajit M W

    2012-11-01

    The success of total knee arthroplasty depends, in part, on the ability of the surgeon to properly manage the soft tissues surrounding the joint, but an objective definition as to what constitutes acceptable postoperative joint stability does not exist. Such a definition may not exist due to lack of suitable instrumentation, as joint stability is currently assessed by visual inspection while the surgeon manipulates the joint. Having the ability to accurately and precisely measure knee stability at the time of surgery represents a key requirement in the process of objectively defining acceptable joint stability. Therefore, we created a novel sterilizable device to allow surgeons to measure varus-valgus, internal-external, or anterior-posterior stability of the knee during a total knee arthroplasty. The device can be quickly adjusted between 0 deg and 90 deg of knee flexion. The device interfaces with a custom surgical navigation system, which records the resultant rotations or translations of the knee while the surgeon applies known loads to a patient's limb with a handle instrumented with a load cell. We validated the performance of the device by having volunteers use it to apply loads to a mechanical linkage that simulated a knee joint; we then compared the joint moments calculated by our stability device against those recorded by a load cell in the simulated knee joint. Validation of the device showed low mean errors (less than 0.21 ± 1.38 Nm and 0.98 ± 3.93 N) and low RMS errors (less than 1.5 Nm and 5 N). Preliminary studies from total knee arthroplasties performed on ten cadaveric specimens also demonstrate the utility of our new device. Eventually, the use of this device may help determine how intra-operative knee stability relates to postoperative function and could lead to an objective definition of knee stability and more efficacious surgical techniques.

  18. Knee Bursitis

    MedlinePlus

    ... make a diagnosis of knee bursitis during a physical exam. Your doctor will inspect your knee by: Comparing the condition of both knees, particularly if only one is painful Gently pressing on different areas of your knee to detect warmth, swelling and the source of pain Carefully moving ...

  19. Biomechanics of hyperflexion and kneeling before and after total knee arthroplasty.

    PubMed

    Lee, Thay Q

    2014-06-01

    The capacity to perform certain activities is frequently compromised after total knee arthroplasty (TKA) due to a functional decline resulting from decreased range of motion and a diminished ability to kneel. In this manuscript, the current biomechanical understanding of hyperflexion and kneeling before and after TKA will be discussed. Patellofemoral and tibiofemoral joint contact area, contact pressure, and kinematics were evaluated in cadaveric studies using a Tekscan pressure measuring system and Microscribe. Testing was performed on intact knees and following cruciate retaining and posterior stabilized TKA at knee flexion angles of 90°, 105°, 120°, and 135°. Three loading conditions were used to simulate squatting, double stance kneeling, and single stance kneeling. Following TKA with double stance kneeling, patellofemoral contact areas did not increase significantly at high knee flexion angle (135°). Kneeling resulted in tibial posterior translation and external rotation at all flexion angles. Moving from double to single stance kneeling tended to increase pressures in the cruciate retaining group, but decreased pressures in the posterior stabilized group. The cruciate retaining group had significantly larger contact areas than the posterior stabilized group, although no significant differences in pressures were observed comparing the two TKA designs (p < 0.05). If greater than 120° of postoperative knee range of motion can be achieved following TKA, then kneeling may be performed with less risk in the patellofemoral joint than was previously believed to be the case. However, kneeling may increase the likelihood of damage to cartilage and menisci in intact knees and after TKA increases in tibiofemoral contact area and pressures may lead to polyethyelene wear if performed on a chronic, repetitive basis.

  20. Retrospective, Demographic, and Clinical Investigation of the Causes of Postoperative Infection in Patients With Lumbar Spinal Stenosis Who Underwent Posterior Stabilization.

    PubMed

    Yaldiz, Can; Yaldiz, Mahizer; Ceylan, Nehir; Kacira, Ozlem Kitiki; Ceylan, Davut; Kacira, Tibet; Kizilcay, Gokhan; Tanriverdi, Taner

    2015-07-01

    Owing to the increasing population of elderly patients, a large number of patients with degenerative spondylosis are currently being surgically treated. Although basic measures for decreasing postoperative surgical infections (PSIs) are considered, it still remains among the leading causes of morbidity and mortality. The aim of this retrospective analysis is to present possible causes leading to PSI in patients who underwent surgery for lumbar degenerative spondylosis and highlight how it can be avoided to decrease morbidity and mortality. The study included 540 patients who underwent posterior stabilization due to degenerative lumbar stenosis between January 2013 and January 2014. The data before and after surgery was retrieved from the hospital charts. Patients with degenerative lumbar stenosis who were operated upon in this study had >2 levels of laminectomy and facetectomy. For this reason, posterior stabilization was performed for all the patients included in this study. Determining the causes of postoperative infection (PI) following spinal surgeries performed with instrumentation is a struggle. Seventeen different parameters that may be related to PI were evaluated in this study. The presence of systemic diseases, unknown glove perforations, and perioperative blood transfusions were among the parameters that increased the prevalence of PI. Alternatively, prolene sutures, double-layered gloves, and the use of rifampicin Sv (RIS) decreased the incidence of PI. Although the presence of systemic diseases, unnoticed glove perforations, and perioperative blood transfusions increased PIs, prolene suture material, double-layered gloves, and the use of RIS decreased PIs.

  1. Retrospective, Demographic, and Clinical Investigation of the Causes of Postoperative Infection in Patients With Lumbar Spinal Stenosis Who Underwent Posterior Stabilization

    PubMed Central

    Yaldiz, Can; Yaldiz, Mahizer; Ceylan, Nehir; Kacira, Ozlem Kitiki; Ceylan, Davut; Kacira, Tibet; Kizilcay, Gokhan; Tanriverdi, Taner

    2015-01-01

    Abstract Owing to the increasing population of elderly patients, a large number of patients with degenerative spondylosis are currently being surgically treated. Although basic measures for decreasing postoperative surgical infections (PSIs) are considered, it still remains among the leading causes of morbidity and mortality. The aim of this retrospective analysis is to present possible causes leading to PSI in patients who underwent surgery for lumbar degenerative spondylosis and highlight how it can be avoided to decrease morbidity and mortality. The study included 540 patients who underwent posterior stabilization due to degenerative lumbar stenosis between January 2013 and January 2014. The data before and after surgery was retrieved from the hospital charts. Patients with degenerative lumbar stenosis who were operated upon in this study had >2 levels of laminectomy and facetectomy. For this reason, posterior stabilization was performed for all the patients included in this study. Determining the causes of postoperative infection (PI) following spinal surgeries performed with instrumentation is a struggle. Seventeen different parameters that may be related to PI were evaluated in this study. The presence of systemic diseases, unknown glove perforations, and perioperative blood transfusions were among the parameters that increased the prevalence of PI. Alternatively, prolene sutures, double-layered gloves, and the use of rifampicin Sv (RIS) decreased the incidence of PI. Although the presence of systemic diseases, unnoticed glove perforations, and perioperative blood transfusions increased PIs, prolene suture material, double-layered gloves, and the use of RIS decreased PIs. PMID:26200620

  2. Knee pain, knee injury, knee osteoarthritis & work.

    PubMed

    Dulay, Gurdeep S; Cooper, C; Dennison, E M

    2015-06-01

    Symptomatic knee osteoarthritis (OA) can be viewed as the end result of a molecular cascade which ensues after certain triggers occur and ultimately results in irreversible damage to the articular cartilage. The clinical phenotype that knee OA can produce is variable and often difficult to accurately predict. This is further complicated by the often poor relationship between radiographic OA and knee pain. As a consequence, it can be difficult to compare studies that use different definitions of OA. However, the literature suggests that while there are multiple causes of knee OA, two have attracted particular attention over recent years; occupation related knee OA and OA subsequent to previous knee injury. The evidence of a relationship, and the strength of this association, is discussed in this chapter.

  3. Multiple osteochondroses of bilateral knee joints: a case report.

    PubMed

    Franceschi, Francesco; Barnaba, Simona Angela; Rojas, Mario; Gualdi, Giancarlo; Rizzello, Giacomo; Papalia, Rocco; Denaro, Vincenzo

    2007-04-01

    Knee injuries in young athletes include not only the typical adult bone injuries, ligament and cartilage, but also the growth plate lesions. Osteochondroses are idiopathic, self-limited disturbance of enchondral ossification in which a rapid growth spurt is present. The patella could be affected by two different kinds of osteochondroses: Kohler syndrome and Sinding-Larsen-Johansson. Here we are reporting the first case of simultaneous location of osteochondroses of the two ossification centers of both patella. A 9-year-old boy, competitive skater, presented a history of anterior knee pain involving both knees. Standard X-rays, axial patellar view, MRI and arthro-MR were performed. In order to follow the natural history of the pathology and the evolution of the healing, examinations at 2 years were repeated. We proposed the young skater a medical and a physiotherapeutic treatment based on unloading, isometric exercises, NSAID. As the symptoms improve a gradual return to competitive sports activity was allowed. The case mentioned above can be considered an atypical case because the patient suffered for a bilateral knee osteochondroses, involving simultaneously the primary ossification centre (Kohler syndrome) and the secondary ossification centre (Larsen syndrome) of the patella.

  4. Jumper's Knee (Patellar Tendonitis)

    MedlinePlus

    ... Surgery? A Week of Healthy Breakfasts Shyness Jumper's Knee KidsHealth > For Teens > Jumper's Knee A A A ... continued damage to the knee. How Does the Knee Work? To understand how jumper's knee happens, it ...

  5. Knee arthroscopy - series (image)

    MedlinePlus

    ... knee problems such as: a torn knee disc (meniscus) a damaged knee bone (patella) a damaged ligament ... surgeon can see the ligaments, the knee disc (meniscus), the knee bone (patella), the lining of the ...

  6. Dynamic finite element knee simulation for evaluation of knee replacement mechanics.

    PubMed

    Baldwin, Mark A; Clary, Chadd W; Fitzpatrick, Clare K; Deacy, James S; Maletsky, Lorin P; Rullkoetter, Paul J

    2012-02-02

    In vitro pre-clinical testing of total knee replacement (TKR) devices is a necessary step in the evaluation of new implant designs. Whole joint knee simulators, like the Kansas knee simulator (KKS), provide a controlled and repeatable loading environment for comparative evaluation of component designs or surgical alignment under dynamic conditions. Experimental testing, however, is time and cost prohibitive for design-phase evaluation of tens or hundreds of design variations. Experimentally-verified computational models provide an efficient platform for analysis of multiple components, sizes, and alignment conditions. The purpose of the current study was to develop and verify a computational model of a dynamic, whole joint knee simulator. Experimental internal-external and valgus-varus laxity tests, followed by dynamic deep knee bend and gait simulations in the KKS were performed on three cadaveric specimens. Specimen-specific finite element (FE) models of posterior-stabilized TKR were created from magnetic resonance images and CAD geometry. The laxity data was used to optimize mechanical properties of tibiofemoral soft-tissue structures on a specimen-specific basis. Each specimen was subsequently analyzed in a computational model of the experimental KKS, simulating both dynamic activities. The computational model represented all joints and actuators in the experimental setup, including a proportional-integral-derivative (PID) controller to drive quadriceps actuation. The computational model was verified against six degree-of-freedom patellofemoral (PF) and tibiofemoral (TF) kinematics and actuator loading during both deep knee bend and gait activities, with good agreement in trends and magnitudes between model predictions and experimental kinematics; differences were less than 1.8 mm and 2.2° for PF and TF translations and rotations. The whole joint FE simulator described in this study can be applied to investigate a wide range of clinical and research questions.

  7. Runner's Knee

    MedlinePlus

    ... name just two. It's the most common overuse injury among runners, but it can also strike other athletes who do activities that require a lot of knee bending, such as biking, jumping, or skiing. Runner's knee happens when the kneecap (patella) tracks incorrectly over a ...

  8. Knee Injuries

    MedlinePlus

    ... keeping it from bending outward. anterior cruciate ligament (ACL): The ACL connects your femur to your tibia at the ... Common knee sprains usually involve damage to the ACL and/or MCL. The most serious sprains involve ...

  9. Knee MRI

    MedlinePlus

    ... of the knee uses a powerful magnetic field, radio waves and a computer to produce detailed pictures of ... scans, MRI does not utilize ionizing radiation. Instead, radio waves redirect alignment of hydrogen atoms that naturally exist ...

  10. Knee Dislocations

    PubMed Central

    Schenck, Robert C.; Richter, Dustin L.; Wascher, Daniel C.

    2014-01-01

    Background: Traumatic knee dislocation is becoming more prevalent because of improved recognition and increased exposure to high-energy trauma, but long-term results are lacking. Purpose: To present 2 cases with minimum 20-year follow-up and a review of the literature to illustrate some of the fundamental principles in the management of the dislocated knee. Study Design: Review and case reports. Methods: Two patients with knee dislocations who underwent multiligamentous knee reconstruction were reviewed, with a minimum 20-year follow-up. These patients were brought back for a clinical evaluation using both subjective and objective measures. Subjective measures include the following scales: Lysholm, Tegner activity, visual analog scale (VAS), Short Form–36 (SF-36), International Knee Documentation Committee (IKDC), and a psychosocial questionnaire. Objective measures included ligamentous examination, radiographic evaluation (including Telos stress radiographs), and physical therapy assessment of function and stability. Results: The mean follow-up was 22 years. One patient had a vascular injury requiring repair prior to ligament reconstruction. The average assessment scores were as follows: SF-36 physical health, 52; SF-36 mental health, 59; Lysholm, 92; IKDC, 86.5; VAS involved, 10.5 mm; and VAS uninvolved, 2.5 mm. Both patients had excellent stability and were functioning at high levels of activity for their age (eg, hiking, skydiving). Both patients had radiographic signs of arthritis, which lowered 1 subject’s IKDC score to “C.” Conclusion: Knee dislocations have rare long-term excellent results, and most intermediate-term studies show fair to good functional results. By following fundamental principles in the management of a dislocated knee, patients can be given the opportunity to function at high levels. Hopefully, continued advances in the evaluation and treatment of knee dislocations will improve the long-term outcomes for these patients in the

  11. Comparative optimism about health and nonhealth events in 8- and 9-year-old children.

    PubMed

    Albery, Ian P; Messer, David

    2005-05-01

    Comparative optimism has been studied extensively in adults and is a significant component of social- cognitive models about health. In contrast, little is known about comparative optimism in children or about the wider social- cognitive processes that underpin their health-related behavior. This study investigated comparative optimism for health- and nonhealth-related topics in 101 children 8 or 9 years of age, the youngest ages that have been investigated so far. Children were shown to be unrealistically optimistic for health and nonhealth events. The implications of these findings for understanding comparative optimism in children are discussed.

  12. Hereditary Sensory and Autonomic Neuropathy Type IV in 9 Year Old Boy: A Case Report

    PubMed Central

    AZADVARI, Mohaddeseh; EMAMI RAZAVI, Seyedeh Zahra; KAZEMI, Shahrbanoo

    2016-01-01

    Objective The Hereditary Sensory and Autonomic neuropathy (HSAN) is a rare group of neuropathies that affects the Sensory and Autonomic nervous system. The patients do not have the ability of sensing different sensations such as pain and temperature, which tends to lead to different injuries. In addition, due to autonomic involvement, the patients suffer from fluctuation in body temperature periodically and lack of precipitation. HSAN is divided into 5 types according to the age of onset, clinical features, and inheritance. Our case was a 9-yr old boy from cousin parents. He had some developmental delay and history of recurrent fever and convulsion in the first year of his life. Gradually, other symptoms added to patient’ feature such as multiple painless skin ulcers, tooth loss, destruction of toes and fingers. In electrodiagnostic study, we found decreased amplitude of sensory nerves, while the other studies were normal. Laboratory test and imaging studies were also normal. All clinical and paraclinical findings were in favor of HSAN type IV. There is no cure for such patients; as a result, these patients and their families need receiving appropriate education and timely rehabilitation services. PMID:27247588

  13. Polychlorinated Biphenyl Exposure and Glucose Metabolism in 9-Year-Old Danish Children

    PubMed Central

    Timmermann, Amalie G.; Rossing, Laura I.; Ried-Larsen, Mathias; Grøntved, Anders; Andersen, Lars B.; Dalgaard, Christine; Hansen, Oluf H.; Scheike, Thomas; Nielsen, Flemming; Grandjean, Philippe

    2014-01-01

    Context: Human exposure to polychlorinated biphenyls (PCBs) has been associated to type 2 diabetes in adults. Objective: We aimed to determine whether concurrent plasma PCB concentration was associated with markers of glucose metabolism in healthy children. Setting and Design: Cross-sectional study of 771 healthy Danish third grade school children ages 8–10 years in the municipality of Odense were recruited in 1997 through a two-stage cluster sampling from 25 schools stratified according to location and socioeconomic character; 509 (9.7 ± 0.8 y, 53% girls) had adequate amounts available for PCB analyses. Outcome Measures: Fasting serum glucose and insulin were measured and a homeostasis assessment model of insulin resistance (HOMA-IR) and β-cell function (HOMA-B) calculated. Plasma PCB congeners and other persistent compounds were measured and ΣPCB calculated. Results: PCBs were present in plasma at low concentrations, median, 0.19 μg/g lipid (interquartile range, 0.12–0.31). After adjustment for putative confounding factors, the second, third, fourth, and fifth quintiles of total PCB were significantly inversely associated with serum insulin (−14.6%, −21.7%, −18.9%, −23.1%, P trend < .01), compared with the first quintile, but not with serum glucose (P = .45). HOMA-IR and HOMA-B were affected in the same direction due to the declining insulin levels with increasing PCB exposure. Similar results were found for individual PCB congeners, for βHCB (hexachlorobenzen) and pp-DDE (dichlorodiphenyldichloroethylene). Conclusions: A strong inverse association between serum insulin and PCB exposure was found while fasting glucose remained within the expected narrow range. Our findings suggest that PCB may not exert effect through decreased peripheral insulin sensitivity, as seen in obese and low-fit children, but rather through a toxicity to β-cells. It remains to be demonstrated whether lower HOMA-B is caused by destruction of β-cell–reducing peripheral insulin resistance and thereby increase fasting glucose as previously found. PMID:25093617

  14. Early parental separation and the psychosocial development of daughters 6-9 years old.

    PubMed

    Japel, C; Tremblay, R E; Vitaro, F; Boulerice, B

    1999-01-01

    The relationship of timing of early parental separation to psychosocial development of daughters was examined in 77 girls, 6-9 years of age over a four-year period. Disruptive behavior across contexts was prevalent in girls separated between birth and two years of age. Girls separated between three and five years of age showed more externalizing behavior problems, but only in school. Results suggest that early parental separation has more pervasive and stable negative effects on psychosocial adjustment of girls in this age group in single-parent families. Implications of the findings and directions for research are discussed.

  15. Childhood Trauma and Multiple Personality Disorder: The Case of a 9-Year-Old Girl.

    ERIC Educational Resources Information Center

    LaPorta, Lauren D.

    1992-01-01

    This paper reports the case of a nine-year-old female victim of sexual abuse, evaluated and diagnosed with multiple personality disorder over a six-month period. Included is a description of the child's presentation with historical and developmental data. A discussion of the dynamic and predisposing features of the case follows, along with…

  16. Implicit and Explicit Knowledge of Linear and Exponential Growth in 5- and 9-Year-Olds

    ERIC Educational Resources Information Center

    Ebersbach, Mirjam; Resing, Wilma C. M.

    2008-01-01

    The present study examined children's implicit and explicit knowledge of linear and non-linear processes. Five- and nine-year-olds (N = 60) were asked to forecast linear and exponential growth by providing the corresponding number of beads. Implicit knowledge was assessed via the magnitudes of the forecasts; explicit knowledge was investigated…

  17. Physiological Alterations in 7- to 9-Year-Old Boys Following a Season of Competitive Wrestling.

    ERIC Educational Resources Information Center

    Clarke, David H.; And Others

    1984-01-01

    Muscular and aerobic capacity changes resulting from three months of wrestling training were examined in a group of normally active seven- to nine-year-old boys. Wrestling training was found to improve strength in young boys, but it did not seem to improve aerobic capacity. (Author/DF)

  18. Response conflict processes' classification in 7 and 9 year old children using EEG brain connectivity measures.

    PubMed

    Almabruk, T; Iyer, K; Girdler, S; Khan, M M; Tan, T

    2016-08-01

    Investigating cognitive development of children poses interesting challenges pertaining to emergence of children's' ability to think and understand. Psychological tasks that involve conflict, like the Flanker task, are widely used to understand development of response conflict processes. In this study, EEG signals were used to examine the coherence and imaginary part of coherency within the delta, theta, alpha and beta bands across different conditions of the Flanker task. Longitudinal data were collected from a group of typically developing children at ages of seven and nine. We found that the imaginary part of coherency was more helpful in distinguishing between stimuli - alpha and beta bands resulted in 90.90% classification rate in seven year old children. The beta and theta bands were found to be more effective for stimuli classification in nine year old children - more than 84.09% classification accuracy was achieved.

  19. Earlier predictors of eating disorder symptoms in 9-year-old children. A longitudinal study.

    PubMed

    Parkinson, Kathryn N; Drewett, Robert F; Le Couteur, Ann S; Adamson, Ashley J

    2012-08-01

    The aim of the study was to examine predictors of eating disorder symptoms in a population based sample at the earliest age at which they can be measured using the Children's Eating Attitudes Test. Data were collected from the longitudinal Gateshead Millennium Study cohort; 609 children participated in the 7 year data sweep (and their mothers and teachers), and 589 children participated in the 9 year data sweep. Eating disorder symptoms at 9 years were higher in boys, and in children from more deprived families. Higher eating disorder symptoms were associated with more body dissatisfaction at 9 years. Higher symptoms were predicted by higher levels of dietary restraint and of emotional symptoms, but not greater body dissatisfaction, 2 years earlier. The study showed that some correlates of high eating disorder symptoms found in adolescents and adults are also found in children, before the rise in diagnosable eating disorders over the pubertal period.

  20. Cabergoline Effectively Induced Remission of Prolactinoma in a 9-year-old Japanese Boy

    PubMed Central

    Sano, Hitomi; Takigami, Masayoshi; Ogino, Tetsuo; Morioka, Keita; Ito, Tomoshiro; Sudo, Akira; Fukushima, Naoki

    2009-01-01

    Prolactinomas are rarely diagnosed in children under the age of 10. A 9-yr-old Japanese boy complained of severe headache and progressive visual disturbance. His growth had been retarded for approximately 3 yr, and his serum PRL level was 811.6 ng/ml. Brain magnetic resonance imaging (MRI) revealed an enlarged pituitary (2.8 × 2.6 × 2.1 cm) with heterogeneous enhancement. He was diagnosed as having a macroprolactinoma accompanied by pituitary apoplexy and growth hormone deficiency. A surgical approach was initially undertaken due to the progressive visual deficits, but a residual tumor was observed, and the level of serum PRL was still high after the surgery. Cabergoline was then started, and the dose was gradually increased to 1.5 mg/wk. The serum PRL level decreased from 138.8 ng/ml to 32.5 ng/ml and 17.7 ng/ml after 5 wk and 19 wk, respectively. At 33 wk of cabergoline treatment, brain MRI demonstrated no evidence of the residual tumor. Thereafter, the serum level of PRL decreased to less than 10 ng/ml, and remission was consistently confirmed on repeated MRI. No adverse events have been observed. The present case suggests that cabergoline can be an effective treatment for prolactinomas in prepubertal children as well as in adults. PMID:24790382

  1. Motor Proficiency of 6- to 9-Year-Old Children with Speech and Language Problems

    ERIC Educational Resources Information Center

    Visscher, Chris; Houwen, Suzanne; Moolenaar, Ben; Lyons, Jim; Scherder, Erik J. A.; Hartman, Esther

    2010-01-01

    Aim: This study compared the gross motor skills of school-age children (mean age 7y 8mo, range 6-9y) with developmental speech and language disorders (DSLDs; n = 105; 76 males, 29 females) and typically developing children (n = 105; 76 males, 29 females). The relationship between the performance parameters and the children's age was investigated…

  2. Stylohyoid Complex (Eagle) Syndrome Starting in a 9-Year-Old Boy.

    PubMed

    Gárriz-Luis, Maite; Irimia, Pablo; Alcalde, Juan M; Domínguez, Pablo; Narbona, Juan

    2017-02-01

    Background There are only four previous pediatric reports of the glossopharyngeal neuralgic form of the stylohyoid complex syndrome. Stylohyoid complex has merely been described as cases of glossopharyngeal neuralgia in children. Case Report A 12-year-old boy came to our hospital because of recurrent episodes of severe cranial pain (9/10) lasting for 5 to 15 minutes. Pain affected the right tonsillar fossa, ear, and mastoid region. Since the start at the age of 9 years, the frequency of painful episodes has progressively increased: when admitted to our clinics 3 years later, the child was having up to five episodes daily in spite of analgesic, antiepileptic, and antidepressant drugs; he had abandoned school and leisure. Between episodes, neurological examination detected only discomfort to pressure on the right tonsillar fossa. Three-dimensional computed tomography images of the skull base showed an elongated right styloid process and bilateral calcification of the stylohyoid ligament. After surgical excision of the right styloid process and of part of the stylohyoid ligament, the glossopharyngeal painful episodes ceased. The patient remains asymptomatic seven years later. Conclusion In spite of its rarity in childhood, this debilitating but treatable syndrome should be kept in mind for the differential diagnosis of recurrent cranial pain in the pediatric population.

  3. The Development of a Scale to Measure Empathy in 8- and 9-Year Old Children

    ERIC Educational Resources Information Center

    Garton, Alison F.; Gringart, Eyal

    2005-01-01

    Empathy has been suggested to facilitate effective collaborative problem solving in children. The current study adapted the Interpersonal Reactivity Index (IRI, Davis, 1980), a well-validated empathy measure for adults, for use with children aged 8 and 9 years. Four hundred and thirteen school children aged between 7;11 and 9;11 years completed…

  4. Decomposing and Connecting Object Representations in 5- to 9-Year-Old Children's Drawing Behaviour

    ERIC Educational Resources Information Center

    Picard, Delphine; Vinter, Annie

    2006-01-01

    This study aimed at specifying the content of the representational redescription (RR) process assumed by Karmiloff-Smith (1992) with respect to the emergence of inter-representational flexibility in children's drawing behaviour. We hypothesized that the RR process included part-whole decomposition processes that are essential to the ability to…

  5. Validity of dietary restraint among 5- to 9-year old girls.

    PubMed

    Shunk, Jennifer A; Birch, Leann L

    2004-06-01

    Dietary restraint is defined as the cognitive tendency to restrict intake and is often accompanied by the breakdown of restraint, referred to as disinhibition, leading to overeating and overweight in adults. Given recent evidence suggesting that dietary restraint and disinhibition are emerging as early as middle childhood, this study examined the validity of the restraint construct as measured in girls between the ages of 5 and 9. Dietary restraint was assessed longitudinally by questionnaire and validity was established by correlating restraint with measures previously reported to be related to restraint including weight concerns, body esteem, self-reported dieting, and measures of dietary intake when girls were ages 5, 7, and 9. Participants were 153 girls from predominately middle class, and exclusively non-Hispanic white families living in central Pennsylvania. Correlational data were used to assess relationships between dietary restraint and weight concerns, body esteem, dietary intake, and dieting. Results from this study indicate that there is evidence for the validity of the dietary restraint construct among girls by age 9. Specifically, dietary restraint was highly and positively associated with body mass index, weight concerns and body dissatisfaction and negatively correlated with dietary intake, findings similar to those reported in the adult literature.

  6. Knee Menisci.

    PubMed

    Bryceland, James Kevin; Powell, Andrew John; Nunn, Thomas

    2017-04-01

    The menisci of the knees are semicircular fibrocartilaginous structures consisting of a hydrophilic extracellular matrix containing a network of collagen fibers, glycoproteins, and proteoglycans maintained by a cellular component. The menisci are responsible for more than 50% of load transmission across the knee and increase joint congruity thereby also aiding in fluid film lubrication of the joint. In the United Kingdom, meniscal tears are the most common form of intra-articular knee injury and one of the commonest indications for orthopedic intervention. The management of these injuries is dependent on the location within the meniscus (relative to peripheral blood supply) and the pattern of tear. Removal of meniscus is known to place the knee at increased risk of osteoarthritis; therefore repair of meniscal tears is preferable. However, a significant proportion of tears are irreparable and can only be treated by partial or even complete meniscectomy. More recent studies have shown encouraging results with meniscal replacement in this situation, though further work is required in this area.

  7. Soft tissue balance changes depending on joint distraction force in total knee arthroplasty.

    PubMed

    Nagai, Kanto; Muratsu, Hirotsugu; Matsumoto, Tomoyuki; Miya, Hidetoshi; Kuroda, Ryosuke; Kurosaka, Masahiro

    2014-03-01

    The influence of joint distraction force on intraoperative soft tissue balance was evaluated using Offset Repo-Tensor® for 78 knees that underwent primary posterior-stabilized total knee arthroplasty. The joint center gap and varus ligament balance were measured between osteotomized surfaces using 20, 40 and 60 lbs of joint distraction force. These values were significantly increased at extension and flexion as the distraction force increased. Furthermore, lateral compartment stiffness was significantly lower than medial compartment stiffness. Thus, larger joint distraction forces led to larger varus ligament balance and joint center gap, because of the difference in soft tissue stiffness between lateral and medial compartments. These findings indicate the importance of the strength of joint distraction force in the assessment of soft tissue balance, especially when using gap-balancing technique.

  8. Knee CT scan

    MedlinePlus

    CAT scan - knee; Computed axial tomography scan - knee; Computed tomography scan - knee ... scanners can perform the exam without stopping.) A computer makes several images of the body area. These ...

  9. Knee pain (image)

    MedlinePlus

    ... front of the knee can be due to bursitis, arthritis, or softening of the patella cartilage as ... knee. Overall knee pain can be due to bursitis, arthritis, tears in the ligaments, osteoarthritis of the ...

  10. Total Knee Replacement

    MedlinePlus

    ... stability. The long thigh muscles give the knee strength. All remaining surfaces of the knee are covered ... physical examination. This will assess knee motion, stability, strength, and overall leg alignment. • X-rays. These images ...

  11. Knee joint replacement

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/002974.htm Knee joint replacement To use the sharing features on this page, please enable JavaScript. Knee joint replacement is a surgery to replace a knee ...

  12. Water on the Knee

    MedlinePlus

    ... your knee joint. Some people call this condition "water on the knee." A swollen knee may be ... Choose low-impact exercise. Certain activities, such as water aerobics and swimming, don't place continuous weight- ...

  13. The use of highly cross-linked polyethylene in total knee arthroplasty.

    PubMed

    Lachiewicz, Paul F; Geyer, Mark R

    2011-03-01

    Polyethylene wear, with resultant particle-induced osteolysis, is a cause of late failure of total knee arthroplasty. The causes of both wear and osteolysis are multifactorial; still, improvements in the polyethylene liner have been investigated. Available highly cross-linked polyethylene tibial liners and patellar prostheses differ greatly in the amount and method of irradiation, thermal treatments, and sterilization techniques they undergo. Several varieties of highly cross-linked polyethylene reduce the gravimetric and volumetric wear of tibial liners in knee simulator studies. However, reduced fracture toughness and the generation of smaller and possibly more reactive particles also have been reported with some varieties of polyethylene. Clinical studies of the use of highly cross-linked polyethylene in total knee arthroplasty are limited. Two nonrandomized trials of highly cross-linked polyethylene in total knee arthroplasty have reported a nonsignificant decrease in radiolucent lines at 2 and 5 years, respectively. The risks of using highly cross-linked polyethylene include fracture of the liner or of a posterior-stabilized tibial post, liner dislodgement or locking mechanism disruption, and possibly more osteolysis. Highly cross-linked polyethylene tibial liners may be considered for younger, more active patients. However, until additional clinical results are available, a cautious approach is warranted to the widespread use of highly cross-linked polyethylene in total knee arthroplasty.

  14. Knee Injuries and Disorders

    MedlinePlus

    Your knee joint is made up of bone, cartilage, ligaments and fluid. Muscles and tendons help the knee joint move. When any of these structures is hurt ... your life. The most common disease affecting the knee is osteoarthritis. The cartilage in the knee gradually wears away, ...

  15. [Chronic knee joint discomfort].

    PubMed

    Wittke, R

    2005-06-23

    Chronic pain in the knee joint is frequently a sign of arthrosis in adults. This must be clearly differentiated from other knee problems. Patellofemoral stress syndrome (occurs mostly in young people) and arthritis with effusion in the knee joint after long and mostly unusual stress also allow only a reduced function of the knee joint. However, even when the knee joint is still fully functional, chronic problems could already exist: For example, for joggers, iliotibial band friction syndrome (runner's knee) or after high unphysiological stress, patellar tendinopathy (jumper's knee). These must be differentiated from pes anserinus syndrome and a plica mediopatellaris.

  16. Knee Bracing: What Works?

    MedlinePlus

    ... that make knee braces claim that their products work well. Scientific studies have not completely agreed. It's not clear what the knee braces actually do. Braces often work better in the laboratory than they do in ...

  17. Partial knee replacement - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series—Normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited ...

  18. Preventing Knee Injuries

    MedlinePlus

    ... as a result of a twisting or pivoting motion. This injury may cause susceptibility to repeat injuries and knee instability, and therefore often requires surgery. Occasionally, a twisting or hyperextension force to the knee may result in a tibial ...

  19. Knee arthroscopy - discharge

    MedlinePlus

    ... remove it. Torn or damaged anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) Inflamed or damaged ... surgery Knee pain Meniscal allograft transplantation Patient Instructions ACL reconstruction - discharge Getting your home ready - knee or ...

  20. Microprocessor prosthetic knees.

    PubMed

    Berry, Dale

    2006-02-01

    This article traces the development of microprocessor prosthetic knees from early research in the 1970s to the present. Read about how microprocessor knees work, functional options, patient selection, and the future of this prosthetic.

  1. Knee braces - unloading

    MedlinePlus

    ... in their knees, they are referring to a type of arthritis called osteoarthritis . Osteoarthritis is caused by wear and tear inside your knee joints. Cartilage, the firm, rubbery tissue that cushions all of ...

  2. Examining the knee joint.

    PubMed

    Monk, Daniel

    2013-04-01

    Appropriate history taking and examination can ensure accurate diagnosis of common knee problems, and rapid and effective interventions or referral to orthopaedic specialists. This article describes the anatomy of the knee joint and discusses relevant history taking, the examination process, special tests and radiology, as well as common knee injuries and their management.

  3. Knee disarticulation after total-knee replacement.

    PubMed

    Lambregts, S A M; Hitters, W M G C

    2002-12-01

    An 89-year-old woman who had a total-knee replacement in the past, underwent a knee disarticulation of the same leg because of an ischaemic foot. Eight (8) months postoperatively the stump is fully weight-bearing and the patient is able to walk safely, using a prosthesis and a walking frame.

  4. Knee Lymphocutaneous Fistula Secondary to Knee Arthroplasty

    PubMed Central

    Pérez-de la Fuente, T.; Sandoval, E.; Alonso-Burgos, A.; García-Pardo, L.; Cárcamo, C.; Caballero, O.

    2014-01-01

    Lower limb lymphorrhea secondary to a surgical procedure is a rare but difficult-to-solve complication. In lower limb, this entity is frequently associated with vascular procedures around the inguinal area. We report on a case of a knee lymphocutaneous fistula secondary to a knee revision arthroplasty. To our knowledge, no previous reports regarding this complication have been published. PMID:25580333

  5. Bilateral fatigue fracture of the femoral components in a cruciate-retaining cementless total knee prosthesis.

    PubMed

    Saito, Shu; Tokuhashi, Yasuaki; Ishii, Takao; Mori, Sei; Hosaka, Kunihiro; Ryu, Keinosuke; Suzuki, Gen

    2011-10-05

    This article reports a case of bilateral fatigue fracture of the femoral components in a cruciate-retaining uncemented total knee arthroplasty (TKA). A 75-year-old woman (height, 158 cm; weight, 72 kg; body mass index, 29.2) had undergone one-stage bilateral TKA for osteoarthritis 11 years previously at the author's institution. Surgery was performed using an uncemented Flexible Nichidai Knee. Equal tension of the collateral ligaments and normal mechanical axis were achieved during the primary procedure. The patient was an ardent lover of the game of badminton and had higher activity levels with daily playing. At 8 years postoperatively, she started complaining of mild pain in both knees. The pain gradually increased, and at 11 years postoperatively, she had difficulty walking. Anteroposterior radiographs showed narrowing of the medial joint space, indicating wear of the polyethylene insert. Lateral radiographs showed signs of broken implants in both knees. There were no signs of gross implant loosening or osteolysis. One-stage revision surgery was performed, and the knees were converted to cemented posterior-stabilized TKAs. At revision, the bilateral femoral components were found to be fractured at the junction between the trochlear flange and the medial condyle, anteriorly to the medial peg. The polyethylene insert showed mild wear at the medial middle portion. In the majority of case reports, stress fractures of the femoral component have predominantly affected the medial condyle, following uncemented implantation of fixed-bearing knees. In this case, failure of bone ingrowth in uncemented components, higher body mass index, and a higher athletic activity led to fatigue fracture of the femoral components.

  6. Failure of Polyethelene Insert Locking Mechanism after a Posterior Stabilised Total Knee Arthroplasty- A Case Report

    PubMed Central

    Reddy, AY Gurava; Rajan, D Soundar; Chiranjeevi, T; Karthik, C; Kiran, E Krishna

    2016-01-01

    Introduction: Disengagement of polyethylene insert used in total knee arthroplasty is a rare but serious complication. Still rarer is disengagement because of failure of tibial insert locking mechanism. We report a previously unpublished complication of polyethylene insert locking mechanism failure in a 10-months-old posterior stabilized total knee arthroplasty in a 70-year-old woman with osteoarthritis for whom Attune (Depuy) knee implant was used. Case Presentation: A 70-year-old female underwent (Attune, Depuy) primary bilateral posterior stabilised total knee arthroplasty in a private hospital. The patient did not have any complaints and had had been functioning well post her arthroplasty. After five months of surgery she had a fall and sustained injury over right hip which was treated with Cemented Bipolar Hemiarthroplasty. Ten months after index surgery, she sustained trivial fall and presented to the same hospital with knee pain and swelling, where the right knee prosthesis was found to be dislocated. An attempted closed reduction under anaesthesia failed, after which she was referred to our centre with an unstable, painful, swollen right knee in a long knee brace. The physical examination at the time of admission showed posterior sag of the tibia, fullness in the postero-lateral corner, quadriceps muscle atrophy without any neurovascular deficit oflower leg. Postero-lateral dislocation was confirmed with radiographs. Surgical error as a possible causative factor was excluded because patient had been functioning well after surgery. Her comorbidities included hypertension and hyponatremia. ESR and CRP were within normal limits. An open reduction surgery was planned. On exposure, polyethylene was found in the postero-lateral corner of the knee. We were not sure that revising the polyethylene alone would suffice as the poly and locking mechanism was of a relatively new design and hence it was decided to proceed with revision of the components. Revision was done

  7. In vivo kinematic evaluation and design considerations related to high flexion in total knee arthroplasty.

    PubMed

    Argenson, Jean-Noël A; Scuderi, Giles R; Komistek, Richard D; Scott, W Norman; Kelly, Michael A; Aubaniac, Jean-Manuel

    2005-02-01

    In designing a posterior-stabilized total knee arthroplasty (TKA) it is preferable that when the cam engages the tibial spine the contact point of the cam move down the tibial spine. This provides greater stability in flexion by creating a greater jump distance and reduces the stress on the tibial spine. In order to eliminate edge loading of the femoral component on the posterior tibial articular surface, the posterior femoral condyles need to be extended. This provides an ideal femoral contact with the tibial articular surface during high flexion angles. To reduce extensor mechanism impingement in deep flexion, the anterior margin of the tibial articular component should be recessed. This provides clearance for the patella and patella tendon. An in vivo kinematic analysis that determined three dimensional motions of the femorotibial joint was performed during a deep knee bend using fluoroscopy for 20 subjects having a TKA designed for deep flexion. The average weight-bearing range-of-motion was 125 degrees . On average, TKA subjects experienced 4.9 degrees of normal axial rotation and all subjects experienced at least -4.4 mm of posterior femoral rollback. It is assumed that femorotibial kinematics can play a major role in patellofemoral kinematics. In this study, subjects implanted with a high-flexion TKA design experienced kinematic patterns that were similar to the normal knee. It can be hypothesized that forces acting on the patella were not substantially increased for TKA subjects compared with the normal subjects.

  8. Does vitamin E-stabilized ultrahigh-molecular-weight polyethylene address concerns of cross-linked polyethylene in total knee arthroplasty?

    PubMed

    Haider, Hani; Weisenburger, Joel N; Kurtz, Steven M; Rimnac, Clare M; Freedman, Jordan; Schroeder, David W; Garvin, Kevin L

    2012-03-01

    Concerns about reduced strength, fatigue resistance, and oxidative stability of highly cross-linked and remelted ultrahigh-molecular-weight polyethylene (UHMWPE) have limited its clinical acceptance for total knee arthroplasty. We hypothesized that a highly cross-linked UHMWPE stabilized with vitamin E would have less oxidation and loss of mechanical properties. We compared the oxidation, in vitro strength, fatigue-crack propagation resistance, and wear of highly cross-linked UHMWPE doped with vitamin E to γ-inert-sterilized direct compression-molded UHMWPE (control). After accelerated aging, the control material showed elevated oxidation, loss of small-punch mechanical properties, and loss of fatigue-crack propagation resistance. In contrast, the vitamin E-stabilized material had minimal changes and exhibited 73% to 86% reduction in wear for both cruciate-retaining and posterior-stabilized total knee arthroplasty designs. Highly cross-linked vitamin E-stabilized UHMWPE performed well in vitro.

  9. Patterns of knee osteoarthritis in Arabian and American knees.

    PubMed

    Hodge, W Andrew; Harman, Melinda K; Banks, Scott A

    2009-04-01

    This study illustrates differences in the cartilage degeneration in osteoarthritic knees in patients with more frequent hyperflexion activities of daily living compared with Western patients. Proximal tibial articular cartilage wear and cruciate ligament condition were assessed in Saudi Arabian and North American patients with varus osteoarthritis undergoing total knee arthroplasty. In anterior cruciate ligament (ACL) intact knees, there were significant differences in wear location, with a clearly more anterior pattern in Saudi Arabian knees. Complete ACL deficiency occurred in 25% of North American knees but only 14% of Saudi Arabian knees. These ACL-deficient knees showed the most severe cartilage wear in both groups and posterior medial wear patterns. Biomechanical descriptions of knee flexion and axial rotation during kneeling or squatting are consistent with the more pronounced anteromedial and posterolateral cartilage wear patterns observed on the Saudi Arabian knees. These observations provide insight into altered knee mechanics in 2 culturally different populations with different demands on knee flexion.

  10. Evidence of a Transition from Perceptual to Category Induction in 3- to 9-Year-Old Children

    ERIC Educational Resources Information Center

    Badger, Julia R.; Shapiro, Laura R.

    2012-01-01

    We examined whether inductive reasoning development is better characterized by accounts assuming an early category bias versus an early perceptual bias. We trained 264 children aged 3 to 9 years to categorize novel insects using a rule that directly pitted category membership against appearance. This was followed by an induction task with…

  11. Effortful Control Mediates Associations of Fetal Growth with Hyperactivity and Behavioural Problems in 7- to 9-Year-Old Children

    ERIC Educational Resources Information Center

    Schlotz, Wolff; Jones, Alexander; Godfrey, Keith M.; Phillips, David I. W.

    2008-01-01

    Background: Inverse associations of fetal growth with behavioural problems in childhood have been repeatedly reported, suggesting long-term effects of the prenatal developmental environment on behaviour later in life. However, no study so far has examined effects on temperament and potential developmental pathways. Temperamental traits may be…

  12. Effects of a Randomized Reading Intervention Study Aimed at 9-Year-Olds: A 5-Year Follow-up.

    PubMed

    Wolff, Ulrika

    2016-05-01

    The present paper reports on a 5-year follow-up of a randomized reading intervention in grade 3 in Sweden. An intervention group (n = 57) received daily training for 12 weeks in phoneme/grapheme mapping, reading comprehension and reading speed, whereas a control group (n = 55) participated in ordinary classroom activities. The main aim was to investigate if there were remaining effects of the intervention on reading-related skills. Previous analyses showed that the intervention group performed significantly better than the control group on spelling, reading speed, reading comprehension and phoneme awareness at the immediate post-test with sustained effects 1 year later. Results from the 5-year follow-up show that the only significant difference between the intervention (n = 47) and the control group (n = 37) was on word decoding. There was also a significant interaction effect of group assignment and initial word decoding, in the way that the lowest-performing students benefitted the most from the intervention. Another aim was to examine if the children identified in a screening (n = 2212) as poor readers in grade 2 still performed worse than typical readers. The analyses showed that the typically developing students (n = 66) outperformed the students identified as poor readers in grade 2 on working memory, spelling, reading comprehension and word decoding. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Preconception and Prenatal Environmental Factors Associated with Communication Impairments in 9 Year Old Children Using an Exposome-Wide Approach

    PubMed Central

    Steer, Colin D.; Bolton, Patrick; Golding, Jean

    2015-01-01

    Although speech and language deficits are common in children and strongly associated with poor educational and social outcomes, little attention has been paid to the antecedents. In this study we used the information from the Avon Longitudinal Study of Parents and Children to examine preconception and prenatal environmental risk factors that were related to communication difficulties in children using the Children’s Communication Checklist (CCC). We used an exposome-wide approach to identify environmental factors univariably associated with the CCC. Taking account of the False Discovery rate, we used a P value of 0.000157 to identify 621 of 3855 items tested. These were then subjected to a series of stepwise linear regression analyses, firstly within 10 domains: personal characteristics, health, development, education, socio-economic variables, lifestyle, home and social environments, life events and chemical and other exposures; and then with the predictive variables from each domain. The final model consisted of 19 variables independently associated with the communication scale. These variables suggested 6 possible mechanisms: stressors primarily associated with socio-economic disadvantage although other lifestyle choices such as a social network of family or friends can ameliorate these effects; indicators of future parenting skills primarily associated with aspects of parental personality; aspects of the home environment; poor maternal health with a novel finding concerning maternal hearing loss; and maternal education which was partially mediated by the child’s IQ. Finally, there may be a mechanism via the maternal diet in pregnancy in particular the consumption of fatty or processed foods. This is the subject of ongoing investigation. PMID:25739097

  14. Ward's area location, physical activity, and body composition in 8- and 9-year-old boys and girls.

    PubMed

    Cardadeiro, Graça; Baptista, Fátima; Zymbal, Vera; Rodrigues, Luís A; Sardinha, Luís B

    2010-11-01

    Bone strength is the result of its material composition and structural design, particularly bone mass distribution. The purpose of this study was to analyze femoral neck bone mass distribution by Ward's area location and its relationship with physical activity (PA) and body composition in children 8 and 9 years of age. The proximal femur shape was defined by geometric morphometric analysis in 88 participants (48 boys and 40 girls). Using dual-energy X-ray absorptiometry (DXA) images, 18 landmarks were digitized to define the proximal femur shape and to identify Ward's area position. Body weight, lean and fat mass, and bone mineral were assessed by DXA, PA by accelerometry, and bone age by the Tanner-Whitehouse III method. Warps analysis with Thin-Plate Spline software showed that the first axis explained 63% of proximal femur shape variation in boys and 58% in girls. Most of this variation was associated with differences in Ward's area location, from the central zone to the superior aspect of the femoral neck in both genders. Regression analysis demonstrated that body composition explained 4% to 7% of the proximal femur shape variation in girls. In boys, body composition variables explained a similar amount of variance, but moderate plus vigorous PA (MVPA) also accounted for 6% of proximal femur shape variation. In conclusion, proximal femur shape variation in children ages 8 and 9 was due mainly to differences in Ward's area position determined, in part, by body composition in both genders and by MVPA in boys. These variables were positively associated with a central Ward's area and thus with a more balanced femoral neck bone mass distribution.

  15. The Development of Geographical and Spatial Concepts and the Concepts of Country and Nationality Among 9 Year Old Scottish Children

    ERIC Educational Resources Information Center

    Towers, James D.

    1974-01-01

    25 nine year old children from the Outer Islands of Orkney were compared with a matched group of 25 children from Kirkwall in order to find out whether any differences existed in the development of geographical and spatial concepts as well as country and nationality. (Editor/RK)

  16. Effects of different practice conditions on acquisition, retention, and transfer of soccer skills by 9-year-old schoolchildren.

    PubMed

    Vera, Juan Granda; Alvarez, José Carlos Barbero; Medina, Mariano Montilla

    2008-04-01

    This study was designed to examine effects of three practice models, blocked, variable, and combined, on the acquisition, retention, and transfer of new motor skills. 67 subjects (M age = 9.5 yr., SD = .3) from the fourth year of primary school (31 boys and 26 girls) were assigned at random to three different practice groups (Blocked = 22, Variable = 23, Combined = 22) to study acquisition of two skills, dribbling a soccer ball and kicking a soccer ball at a stationary target using the dominant foot. All participants received a pretest and posttest, a transfer test, and a retention test 2 wk. later. Analysis showed significant improvement after practice of kicking skills by the three groups but not in the dribbling skills, for which only the combined practice group showed any notable improvement. At the end of acquisition, the combined practice group had significantly better performance on the dribbling task than the other two groups. However, the only differences noted in performance of kicking the ball with the dominant foot were by combined practice and blocked groups.

  17. Preconception and prenatal environmental factors associated with communication impairments in 9 year old children using an exposome-wide approach.

    PubMed

    Steer, Colin D; Bolton, Patrick; Golding, Jean

    2015-01-01

    Although speech and language deficits are common in children and strongly associated with poor educational and social outcomes, little attention has been paid to the antecedents. In this study we used the information from the Avon Longitudinal Study of Parents and Children to examine preconception and prenatal environmental risk factors that were related to communication difficulties in children using the Children's Communication Checklist (CCC). We used an exposome-wide approach to identify environmental factors univariably associated with the CCC. Taking account of the False Discovery rate, we used a P value of 0.000157 to identify 621 of 3855 items tested. These were then subjected to a series of stepwise linear regression analyses, firstly within 10 domains: personal characteristics, health, development, education, socio-economic variables, lifestyle, home and social environments, life events and chemical and other exposures; and then with the predictive variables from each domain. The final model consisted of 19 variables independently associated with the communication scale. These variables suggested 6 possible mechanisms: stressors primarily associated with socio-economic disadvantage although other lifestyle choices such as a social network of family or friends can ameliorate these effects; indicators of future parenting skills primarily associated with aspects of parental personality; aspects of the home environment; poor maternal health with a novel finding concerning maternal hearing loss; and maternal education which was partially mediated by the child's IQ. Finally, there may be a mechanism via the maternal diet in pregnancy in particular the consumption of fatty or processed foods. This is the subject of ongoing investigation.

  18. [Relation of visual evoked potentials to the integral characteristics of cognitive activity in 8- to 9-year-old children].

    PubMed

    Mariutina, T M; Borodulina, N F; Mel'nikov, G B

    1987-01-01

    Amplitude and temporal parameters of evoked potentials (EPs) in response to a checkerboard pattern, picture of a house, the Russian word "dom", meaning house, combination of letters "DMO" and a number of other stimuli, correlated with indices of the verbal, nonverbal, and general intelligence as well as with those of the cognitive style "field dependence-independence". Maximum number of statistically significant correlations was found in the course of comparison of integrative cognitive characteristics and parameters of EPs to stimuli with increased semantic complexity. No interhemispheric differences were found in the character of interrelations between cognitive characteristics and parameters of EPs to verbal and spatially structured stimuli.

  19. Jumper's Knee (Patellar Tendonitis)

    MedlinePlus

    ... regularly play sports that involve a lot of repetitive jumping — like track and field (particularly high-jumping), basketball, volleyball, gymnastics, running, and soccer — can put a lot of strain on their knees. Jumper's knee can seem like a minor injury that isn't really that serious. Because of ...

  20. Tuberculosis of the knee

    PubMed Central

    Lidder, Surjit; Lang, Kathryn; Haroon, Mallick; Shahidi, Mitra; El-Guindi, Magdi

    2009-01-01

    Extrapulmonary manifestations of tuberculosis are reported in less than one in five cases with the knee affected in 8% after the spine and hip. We report a case of isolated highly erosive tuberculosis of the knee presenting in a previously fit Vietnamese woman. The difficulties of diagnosis, modalities of chemotherapeutic management, and surgical treatment are discussed. PMID:21808686

  1. Partial knee replacement

    MedlinePlus

    ... American Academy of Orthopedic Surgeons (AAOS). Treatment of osteoarthritis of the knee: Evidence-based guideline 2nd edition (summary). Rosemont, IL. ... al. American Academy of Orthopaedic Surgeons. Treatment of osteoarthritis of the knee (nonarthroplasty). J Am Acad Orthop Surg . 2009;17: ...

  2. Pneumatic osteoarthritis knee brace.

    PubMed

    Stamenović, Dimitrije; Kojić, Milos; Stojanović, Boban; Hunter, David

    2009-04-01

    Knee osteoarthritis is a chronic disease that necessitates long term therapeutic intervention. Biomechanical studies have demonstrated an improvement in the external adduction moment with application of a valgus knee brace. Despite being both efficacious and safe, due to their rigid frame and bulkiness, current designs of knee braces create discomfort and difficulties to patients during prolonged periods of application. Here we propose a novel design of a light osteoarthritis knee brace, which is made of soft conforming materials. Our design relies on a pneumatic leverage system, which, when pressurized, reduces the excessive loads predominantly affecting the medial compartment of the knee and eventually reverses the malalignment. Using a finite-element analysis, we show that with a moderate level of applied pressure, this pneumatic brace can, in theory, counterbalance a greater fraction of external adduction moment than the currently existing braces.

  3. Advanced concepts in knee arthrodesis

    PubMed Central

    Wood, Jennifer H; Conway, Janet D

    2015-01-01

    The aim is to describe advanced strategies that can be used to diagnose and treat complications after knee arthrodesis and to describe temporary knee arthrodesis to treat infected knee arthroplasty. Potential difficult complications include nonunited knee arthrodesis, limb length discrepancy after knee arthrodesis, and united but infected knee arthrodesis. If a nonunited knee arthrodesis shows evidence of implant loosening or failure, then bone grafting the nonunion site as well as exchange intramedullary nailing and/or supplemental plate fixation are recommended. If symptomatic limb length discrepancy cannot be satisfactorily treated with a shoe lift, then the patient should undergo tibial lengthening over nail with a monolateral fixator or exchange nailing with a femoral internal lengthening device. If a united knee arthrodesis is infected, the nail must be removed. Then the surgeon has the option of replacing it with a long, antibiotic cement-coated nail. The authors also describe temporary knee arthrodesis for infected knee arthroplasty in patients who have the potential to undergo insertion of a new implant. The procedure has two goals: eradication of infection and stabilization of the knee. A temporary knee fusion can be accomplished by inserting both an antibiotic cement-coated knee fusion nail and a static antibiotic cement-coated spacer. These advanced techniques can be helpful when treating difficult complications after knee arthrodesis and treating cases of infected knee arthroplasty. PMID:25793160

  4. Evolution of knee kinematics three months after total knee replacement.

    PubMed

    Alice, Bonnefoy-Mazure; Stéphane, Armand; Yoshisama, Sagawa Junior; Pierre, Hoffmeyer; Domizio, Suvà; Hermes, Miozzari; Katia, Turcot

    2015-02-01

    In patients with debilitating knee osteoarthritis, total knee replacement is the most common surgical procedure. Numerous studies have demonstrated that knee kinematics one year after total knee replacement are still altered compared to the healthy joint. However, little is known regarding impairments and functional limitations of patients several months after total knee replacement. The aim of this study was to describe the evolution of the knee gait kinematic in patients with knee osteoarthritis before and three months after a total knee replacement. Ninety patients who were to undergo total knee replacement were included in this study. Twenty-three subjects were recruited as the control group. Three-dimensional gait analysis was performed before and three months after surgery. The spatio-temporal parameters and three-dimensional knee kinematics for the operated limb were evaluated during a comfortable gait and compared between groups (the before and after surgery groups and the control group). Three months after surgery, patients always walk with a slower gait velocity and lower knee flexion-extension movements compared to the control group. However, a degree of progress was observed in term of the stride and step length, gait velocity and knee alignment in the coronal plane. Our results suggest that the disability is still significant for most patients three months after total knee replacement. A better understand of the impairments and functional limitations following surgery would help clinicians design rehabilitation programs. Moreover, patients should be informed that rehabilitation after total knee replacement is a long process.

  5. Knee Conditioning Program

    MedlinePlus

    ... muscles help your knee joint absorb shock. Flexibility: Stretching the muscles that you strengthen is important for restoring range of motion and preventing injury. Gently stretching after strengthening exercises can help reduce muscle soreness ...

  6. Anterior knee pain

    MedlinePlus

    ... places extra stress on the kneecap (such as running, jumping or twisting, skiing, or playing soccer). You ... noticeable with: Deep knee bends Going down stairs Running downhill Standing up after sitting for awhile

  7. Prosthetic Knee Systems

    MedlinePlus

    ... must give support when people stand, allow smooth motion when people walk, and permit movement when people ... of knees and their options for stability and motion control would work best for them. There are ...

  8. Knee microfracture surgery

    MedlinePlus

    ... WM, Griesser MJ, Parker RD. Patellofemoral pain. In: Miller MD, Thompson SR, eds. DeLee and Drez's Orthopaedic ... ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 105. Miller RH, Azar FM. Knee injuries. In: Canale ST, ...

  9. Runners knee (image)

    MedlinePlus

    ... forces on the knee, such as a misaligned patella. Chondromalacia is treated with rest or immobilization and nonsteroidal anti-inflammatory drugs for pain. Physical therapy, especially ... alignment of the patella that cannot be corrected with therapy.

  10. Dashboard (in the) Knee

    PubMed Central

    Qureshi, AA; Green, TP

    2015-01-01

    We present the case of a 19-year-old individual presenting to an orthopaedic outpatient clinic several months following a dashboard knee injury during a road traffic accident with intermittent mechanical symptoms. Despite unremarkable examination findings and normal magnetic resonance imaging, the patient was identified subsequently as having an intra-articular plastic foreign body consistent with a piece of dashboard on arthroscopic knee assessment, the retrieval of which resulted in a complete resolution of symptoms. PMID:25723676

  11. Alterations in walking knee joint stiffness in individuals with knee osteoarthritis and self-reported knee instability.

    PubMed

    Gustafson, Jonathan A; Gorman, Shannon; Fitzgerald, G Kelley; Farrokhi, Shawn

    2016-01-01

    Increased walking knee joint stiffness has been reported in patients with knee osteoarthritis (OA) as a compensatory strategy to improve knee joint stability. However, presence of episodic self-reported knee instability in a large subgroup of patients with knee OA may be a sign of inadequate walking knee joint stiffness. The objective of this work was to evaluate the differences in walking knee joint stiffness in patients with knee OA with and without self-reported instability and examine the relationship between walking knee joint stiffness with quadriceps strength, knee joint laxity, and varus knee malalignment. Overground biomechanical data at a self-selected gait velocity was collected for 35 individuals with knee OA without self-reported instability (stable group) and 17 individuals with knee OA and episodic self-reported instability (unstable group). Knee joint stiffness was calculated during the weight-acceptance phase of gait as the change in the external knee joint moment divided by the change in the knee flexion angle. The unstable group walked with lower knee joint stiffness (p=0.01), mainly due to smaller heel-contact knee flexion angles (p<0.01) and greater knee flexion excursions (p<0.01) compared to their knee stable counterparts. No significant relationships were observed between walking knee joint stiffness and quadriceps strength, knee joint laxity or varus knee malalignment. Reduced walking knee joint stiffness appears to be associated with episodic knee instability and independent of quadriceps muscle weakness, knee joint laxity or varus malalignment. Further investigations of the temporal relationship between self-reported knee joint instability and walking knee joint stiffness are warranted.

  12. Runner's knee injuries.

    PubMed

    Lutter, L D

    1984-01-01

    In our series of running injuries 40% of all injuries have been related to the knee area. Over 20 million people in the United States run on a regular basis. Figures from large running sources show that 60% to 70% of individuals running regularly are injured severely enough to temporarily stop running. The figures are significant, not in the seriousness of the knee injury, but in the fact that seeking treatment for their knee problems. Orthopaedic surgeons, because of their ability to evaluate the entire lower extremity, become the central component for treatment of this large group of injured runners. As has been noted, the underlying biomechanical abnormality must be sought and dealt with or the symptoms return. By identification of the injured structure(s) integrated with biomechanical understanding, treatment can be developed on a rational basis, dealing with acute problems and prevention of future ones.

  13. Cementless total knee arthroplasty

    PubMed Central

    Risitano, Salvatore; Sabatini, Luigi; Giachino, Matteo; Agati, Gabriele; Massè, Alessandro

    2016-01-01

    Interest for uncemented total knee arthroplasty (TKA) has greatly increased in recent years. This technique, less used than cemented knee replacement in the last decades, sees a revival thanks an advance in prosthetic design, instrumentation and operative technique. The related literature in some cases shows conflicting data on survival and on the revision’s rate, but in most cases a success rate comparable to cemented TKA is reported. The optimal fixation in TKA is a subject of debate with the majority of surgeons favouring cemented fixation. PMID:27162779

  14. Trunk muscle action compensates for reduced quadriceps force during walking after total knee arthroplasty.

    PubMed

    Li, Katherine; Ackland, David C; McClelland, Jodie A; Webster, Kate E; Feller, Julian A; de Steiger, Richard; Pandy, Marcus G

    2013-05-01

    Patients with total knee arthroplasty (TKA) frequently exhibit changes in gait biomechanics post-surgery, including decreased ranges of joint motion and changes in joint loading; however, the actions of the lower-limb muscles in generating joint moments and accelerating the center of mass (COM) during walking are yet to be described. The aim of the present study was to evaluate differences in lower-limb joint kinematics, muscle-generated joint moments, and muscle contributions to COM accelerations in TKA patients and healthy age-matched controls when both groups walk at the same speed. Each TKA patient was fitted with a posterior-stabilized total knee replacement and underwent patellar resurfacing. Three-dimensional gait analysis and subject-specific musculoskeletal modeling were used to determine lower-limb and trunk muscle forces and muscle contributions to COM accelerations during the stance phase of gait. The TKA patients exhibited a 'quadriceps avoidance' gait pattern, with the vasti contributing significantly less to the extension moment developed about the knee during early stance (p=0.036). There was a significant decrease in the contribution of the vasti to the vertical acceleration (support) (p=0.022) and forward deceleration of the COM (braking) (p=0.049) during early stance; however, the TKA patients compensated for this deficiency by leaning their trunks forward. This significantly increased the contribution of the contralateral back extensor muscle (erector spinae) to support (p=0.030), and that of the contralateral back rotators (internal and external obliques) to braking (p=0.004). These findings provide insight into the biomechanical causes of post-operative gait adaptations such as 'quadriceps avoidance' observed in TKA patients.

  15. Relationship between Tibial Baseplate Design and Rotational Alignment Landmarks in Primary Total Knee Arthroplasty

    PubMed Central

    Indelli, Pier Francesco; Graceffa, Angelo; Baldini, Andrea; Payne, Brielle; Pipino, Gennaro; Marcucci, Massimiliano

    2015-01-01

    This study evaluated the influence of modern tibial baseplate designs when using the anterior tibial cortex as a primary rotational landmark for the tibial baseplate in TKA. Eighty patients undergoing TKA were randomized in two groups. Group 1 included 25 females and 15 males receiving a posterior-stabilized (PS) symmetric tibial baseplate while Group 2 included 24 females and 16 males receiving a PS anatomical tibial component. Identical surgical technique, including the use of the surgical transepicondylar femoral axis (sTEA) and the anterior tibial cortex (“Curve-on-Curve”) as rotational alignment landmarks, was used. All patients underwent CT evaluation performed with the knee in full extension. Three observers independently measured the rotational alignment of the tibial component in relation to the sTEA. The rotational alignment of the symmetric baseplate showed an average external rotation of 1.3° (minimum 5°, maximum −1°): 91% of the knees showed 0 ± 3° with respect to the surgical sTEA, being internally rotated in 20%. The rotational alignment of the anatomical baseplate showed an average external rotation of 4.1° (minimum 0.4°, maximum 8.9°): only 47.5% of the knees showed 0 ± 3°, being externally rotated in 100%. The difference between the two groups was statistically significant. This study confirms the reliability of the “Curve-on-Curve” technique as an adequate rotational alignment anatomical landmark in TKA: the use of an asymmetric tibial baseplate might lead to external rotation of the tibial component when this technique is intraoperatively chosen. PMID:26491564

  16. Reading Knee-Deep

    ERIC Educational Resources Information Center

    Jewett, Pamela

    2007-01-01

    Freire told his audience at a seminar at the University of Massachusetts, "You need to read knee-deep in texts, for deeper than surface meanings, and you need to know the words to be able to do it" (quoted in Cleary, 2003). In a children's literature class, fifteen teachers and I traveled along a path that moved us toward reading…

  17. Hypermobility and Knee Injuries.

    ERIC Educational Resources Information Center

    Steiner, Mark E.

    1987-01-01

    A review of research on the effect of hypermobility on knee injury indicates that greater than normal joint flexibility may be necessary for some athletic endeavors and that it may be possible to change one's underlying flexibility through training. However, for most athletes, inherited flexibility probably plays only a small role, if any, in…

  18. Custom Knee Device for Knee Contractures After Internal Femoral Lengthening.

    PubMed

    Bhave, Anil; Shabtai, Lior; Ong, Peck-Hoon; Standard, Shawn C; Paley, Dror; Herzenberg, John E

    2015-07-01

    The development of knee flexion contractures is among the most common problems and complications associated with lengthening the femur with an internal device or external fixator. Conservative treatment strategies include physical therapy, serial casting, and low-load prolonged stretching with commercially available splinting systems. The authors developed an individually molded, low-cost custom knee device with polyester synthetic conformable casting material to treat knee flexion contractures. The goal of this study was to evaluate the results of treatment with a custom knee device and specialized physical therapy in patients who had knee flexion contracture during femoral lengthening with an intramedullary lengthening femoral nail. This retrospective study included 23 patients (27 limbs) who underwent femoral lengthening with an internal device for the treatment of limb length discrepancy. All patients had a knee flexion contracture raging from 10° to 90° during the lengthening process and were treated with a custom knee device and specialized physical therapy. The average flexion contracture before treatment was 36°. The mean amount of lengthening was 5.4 cm. After an average of 3.8 weeks of use of the custom knee device, only 2 of 27 limbs (7.5%) had not achieved complete resolution of the flexion contracture. The average final extension was 1.4°. Only 7 of 27 limbs (26%) required additional soft tissue release. The custom knee device is an inexpensive and effective method for treating knee flexion contracture after lengthening with an internal device.

  19. 21 CFR 888.3590 - Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Knee joint tibial (hemi-knee) metallic resurfacing... Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis is a device intended to be...

  20. 21 CFR 888.3590 - Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Knee joint tibial (hemi-knee) metallic resurfacing... Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis is a device intended to be...

  1. 21 CFR 888.3580 - Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Knee joint patellar (hemi-knee) metallic... § 888.3580 Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis is a device made...

  2. 21 CFR 888.3580 - Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Knee joint patellar (hemi-knee) metallic... § 888.3580 Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis is a device made...

  3. 21 CFR 888.3580 - Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Knee joint patellar (hemi-knee) metallic... § 888.3580 Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis is a device made...

  4. 21 CFR 888.3580 - Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Knee joint patellar (hemi-knee) metallic... § 888.3580 Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis is a device made...

  5. 21 CFR 888.3590 - Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Knee joint tibial (hemi-knee) metallic resurfacing... Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis is a device intended to be...

  6. 21 CFR 888.3590 - Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint tibial (hemi-knee) metallic resurfacing... Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis is a device intended to be...

  7. Knee Power Is an Important Parameter in Understanding Medial Knee Joint Load in Knee Osteoarthritis

    PubMed Central

    Calder, Kristina M; Acker, Stacey M; Arora, Neha; Beattie, Karen A; Callaghan, Jack P; Adachi, Jonathan D; Maly, Monica R

    2014-01-01

    Objective To determine the extent to which knee extensor strength and power explain variance in knee adduction moment (KAM) peak and impulse in clinical knee osteoarthritis (OA). Methods Fifty-three adults (mean ± SD age 61.6 ± 6.3 years, 11 men) with clinical knee OA participated. The KAM waveform was calculated from motion and force data and ensemble averaged from 5 walking trials. The KAM peak was normalized to body mass (Nm/kg). The mean KAM impulse reflected the mean total medial knee load during stride (Nm × seconds). For strength, the maximum knee extensor moment attained from maximal voluntary isometric contractions (MVIC) was normalized to body mass (Nm/kg). For power, the maximum knee extensor power during isotonic contractions, with the resistance set at 25% of MVIC, was normalized to body mass (W/kg). Covariates included age, sex, knee pain on the Knee Injury and Osteoarthritis Outcome Score, gait speed, and body mass index (BMI). Relationships of the KAM peak and impulse with strength and power were examined using sequential stepwise forward linear regressions. Results Covariates did not explain variance in the KAM peak. While extensor strength did not, peak knee extensor power explained 8% of the variance in the KAM peak (P = 0.02). Sex and BMI explained 24% of the variance in the KAM impulse (P < 0.05). Sex, BMI, and knee extensor power explained 31% of the variance in the KAM impulse (P = 0.02), with power contributing 7% (P < 0.05). Conclusion Knee extensor power was more important than isometric knee strength in understanding medial knee loads during gait. PMID:24920175

  8. Management of the Swollen Knee

    PubMed Central

    Stanish, William D.; Rice, William; Ratson, Gary; Loebenberg, Mark; Langley, Linda

    1988-01-01

    The primary-care physician plays a critical role in the diagnosis, initial treatment, and subsequent rehabilitation of many orthopedic conditions. The knee is the most frequently injured joint in sport medicine. The family physician must therefore be familiar with the etiology, cause, and natural history of problems related to the knee joint. The swollen knee is one of the most common ailments the family physician is asked to assess in his or her busy day-to-day practice of medicine. He or she must therefore remain abreast of the dynamic field of diagnostic procedures, treatments, and rehabilitative measures relating to many knee injuries. This paper deals with the more common causes of the acutely swollen knee, paying particular attention to the infected knee and the acute hemarthrosis. It should provide answers to most questions about diagnosis, initial treatment, and subsequent management of this problem. PMID:21264033

  9. Selectively lockable knee brace

    NASA Technical Reports Server (NTRS)

    Myers, Neill (Inventor); Shadoan, Mike (Inventor); Forbes, John (Inventor); Baker, Kevin (Inventor)

    1994-01-01

    A knee brace for aiding in rehabilitation of damaged leg muscles includes upper and lower housings, normally pivotable, one relative to the other about the knee joint axis of a patient. The upper housing is attachable to the thigh of the patient above the knee joint, while the lower housing is secured to a stirrup which extends downwardly along the patient's leg and is attached to the patient's shoe. An actuation rod is carried within the lower housing and is coupled to a cable. The upper and lower housings carry cooperative clutch/brake elements which normally are disengaged to permit relative movement between the upper and lower housings. When the cable is extended, the clutch/brake elements engage and lock the housings together. A heel strike mechanism fastened to the stirrup and the heel of the shoe is connected to the cable to selectively extend the cable and lock the brace in substantially any position when the patient places weight on the heel.

  10. Selectively Lockable Knee Brace

    NASA Technical Reports Server (NTRS)

    Myers, W. Neill (Inventor); Shadoan, Michael D. (Inventor); Forbes, John C. (Inventor); Baker, Kevin J. (Inventor); Rice, Darron C. (Inventor)

    1996-01-01

    A knee brace for aiding in rehabilitation of damaged leg muscles includes upper and lower housings normally pivotable one relative to the other about the knee joint axis of a patient. The upper housing is attachable to the thigh of the patient above the knee joint while the lower housing is secured to a stirrup which extends downwardly along the patient's leg and is attached to the patient's shoe. An actuation rod is carried within the lower housing and is coupled to a cable. The upper and lower housings carry cooperative clutch/brake elements which normally are disengaged to permit relative movement between the upper and lower housings. When the cable is extended the clutch/brake elements engage and lock the housings together. A heel strike mechanism fastened to the stirrup and the heel of the shoe is connected to the cable to selectively extend the cable and lock the brace in substantially any position when the patient places weight on the heel.

  11. [Physical activity for knee osteoarthritis.

    PubMed

    Nagao, Masashi; Ishijima, Muneaki; Kaneko, Haruka; Takazawa, Yuji; Ikeda, Hiroshi; Kaneko, Kazuo

    Elder populations have been increasing in Japan and estimated 24 million people have knee osteoarthritis(OA). Recently, people have diverse sociological background and demand for participating sports has been growing. People may participate sports to prevent some diseases such as locomotive syndrome. According to the recent studies, excessive high impact sports increase the risk of OA, while daily life exercise decrease the risk. Epidemiological approach demonstrated that reduced knee extension muscle strength increases the risk of OA. We reviewed and discussed the recent topics including efficacy of physical therapy for knee OA and how much sports activities could be beneficial after knee surgery.

  12. Knee stabilization in patients with medial compartment knee osteoarthritis

    PubMed Central

    Lewek, Michael D.; Ramsey, Dan K.; Snyder-Mackler, Lynn; Rudolph, Katherine S.

    2005-01-01

    OBJECTIVE Individuals with medial knee osteoarthritis (MKOA) experience knee laxity and instability. Muscle stabilization strategies may influence the long term integrity of the joint. In this study we determined how individuals with medial knee OA respond to a rapid valgus knee movement to investigate the relationship between muscle stabilization strategies and knee instability. METHODS Twenty one subjects with MKOA and genu varum, and 19 control subjects were tested. Subjects stood with the test limb on a moveable platform that translated laterally to rapidly stress the knee’s medial periarticular structures and create a potentially destabilizing feeling at the knee joint. Knee motion and muscle responses were recorded. Subjects rated their knee instability with a self-report questionnaire about knee instability during daily activities. RESULTS Prior to plate movement the OA subjects demonstrated more medial muscle co-contraction (p=0.014). Following plate movement the OA subjects shifted less weight off the test limb (p = 0.013) and had more medial co-contraction (p=0.037). Those without instability had higher VMMH co-contraction than those who reported more instability (p=0.038). Knee stability correlated positively with VMMH co-contraction prior to plate movement (r = 0.459; p = 0.042). CONCLUSION This study demonstrates that individuals with MKOA attempt to stabilize the knee with greater medial muscle co-contraction in response to laxity that appears on only the medial side of the joint. This strategy presumably contributes to higher joint compression and could exacerbate joint destruction and needs to be altered to slow or stop the progression of the OA disease process. PMID:16142714

  13. Biomechanical effects of total knee arthroplasty component malrotation: a computational simulation.

    PubMed

    Thompson, Julie A; Hast, Michael W; Granger, Jeffrey F; Piazza, Stephen J; Siston, Robert A

    2011-07-01

    Modern total knee arthroplasty (TKA) is an effective procedure to treat pain and disability due to osteoarthritis, but some patients experience quadriceps weakness after surgery and have difficulty performing important activities of daily living. The success of TKA depends on many factors, but malalignment of the prosthetic components is a major cause of postoperative complications. Significant variability is associated with femoral and tibial component rotational alignment, but how this variability translates into functional outcome remains unknown. We used a forward-dynamic computer model of a simulated squatting motion to perform a parametric study of the effects of variations in component rotational alignment in TKA. A cruciate-retaining and posterior-stabilized version of the same TKA implant were compared. We found that femoral rotation had a greater effect on quadriceps forces, collateral ligament forces, and varus/valgus kinematics, while tibial rotation had a greater effect on anteroposterior translations. Our findings support the tendency for orthopedic surgeons to bias the femoral component into external rotation and avoid malrotation of the tibial component.

  14. Medial pivot knee in primary total knee arthroplasty.

    PubMed

    Atzori, Francesco; Salama, Wael; Sabatini, Luigi; Mousa, Shazly; Khalefa, Abdelrahman

    2016-01-01

    Total knee arthroplasty (TKA) with a medial pivot design was developed in order to mimic normal knee kinematics; the highly congruent medial compartment implant should improve clinical results and decrease contact stresses. Clinical and radiographic mid-term outcomes are satisfactory, but we need other studies to evaluate long-term results and indications for unusual cases.

  15. New Generation Lockable Knee Brace

    NASA Technical Reports Server (NTRS)

    1996-01-01

    A knee brace that uses Space Shuttle propulsion technology has moved a step closer to being available to help knee injury and stroke patients and may possibly benefit patients with birth defects, spinal cord injuries, and post-polio conditions. After years of hard work, inventors at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama, have turned over the final design and prototype to industry partners at Horton's Orthotic Lab in Little Rock, Arkansas for further clinical testing. The device, called the Selectively Lockable Knee Brace, may mean faster, less painful rehabilitation for patients by allowing the knee to move when weight is not on the heel. Devices currently on the market lock the knee in a rigid, straight-leg position, or allow continuous free motion. Pictured here is a knee brace prototype being tested and fitted at Horton's Orthotic Lab. The knee brace is just one example of how space technology is being used to improve the lives of people on Earth. NASA's MSFC inventors Michael Shadoan and Neill Myers are space propulsion engineers who use the same mechanisms and materials to build systems for rockets that they used to design and develop the knee brace.

  16. Automatic locking orthotic knee device

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce C. (Inventor)

    1993-01-01

    An articulated tang in clevis joint for incorporation in newly manufactured conventional strap-on orthotic knee devices or for replacing such joints in conventional strap-on orthotic knee devices is discussed. The instant tang in clevis joint allows the user the freedom to extend and bend the knee normally when no load (weight) is applied to the knee and to automatically lock the knee when the user transfers weight to the knee, thus preventing a damaged knee from bending uncontrollably when weight is applied to the knee. The tang in clevis joint of the present invention includes first and second clevis plates, a tang assembly and a spacer plate secured between the clevis plates. Each clevis plate includes a bevelled serrated upper section. A bevelled shoe is secured to the tank in close proximity to the bevelled serrated upper section of the clevis plates. A coiled spring mounted within an oblong bore of the tang normally urges the shoes secured to the tang out of engagement with the serrated upper section of each clevic plate to allow rotation of the tang relative to the clevis plate. When weight is applied to the joint, the load compresses the coiled spring, the serrations on each clevis plate dig into the bevelled shoes secured to the tang to prevent relative movement between the tang and clevis plates. A shoulder is provided on the tang and the spacer plate to prevent overextension of the joint.

  17. Exercise and the Knee Joint.

    ERIC Educational Resources Information Center

    Clarke, H. Harrison, Ed.

    1976-01-01

    This report by the President's Council on Physical Fitness and Sports examines the effects of various forms of physical exercise on the knee joint which, because of its vulnerability, is especially subject to injury. Discussion centers around the physical characteristics of the joint, commonly used measurements for determining knee stability,…

  18. [Arthroscopic treatment for osteoarthritic knee].

    PubMed

    Bloom, Shlomo; Lebel, David; Cohen, Eugen; Atar, Dan; Rath, Ehud

    2008-04-01

    Osteoarthritis (OA) is the leading cause of knee morbidity. Age and overweight are the main risk factors for development of knee OA. The majority of patients respond to conservative treatment. For those who don't, surgical treatment is the only alternative. Arthroscopic surgery for the osteoarthritic knee is a well known procedure. Recently, numerous publications addressed the advantages of arthroscopic treatment for this indication. Some of the publications concluded that arthroscopic treatment for knee OA equals placebo. Others found temporary relief of symptoms. Among special subgroup of patients, in which acute pain exacerbation, mechanical block or early OA, utilizing arthroscopic techniques revealed satisfactory results. In this review, we discuss the indications and contraindications for arthroscopic treatment of the osteoarthritic knee according to the latest literature.

  19. Anterior knee pain.

    PubMed

    LLopis, Eva; Padrón, Mario

    2007-04-01

    Anterior knee pain is a common complain in all ages athletes. It may be caused by a large variety of injuries. There is a continuum of diagnoses and most of the disorders are closely related. Repeated minor trauma and overuse play an important role for the development of lesions in Hoffa's pad, extensor mechanism, lateral and medial restrain structures or cartilage surface, however usually an increase or change of activity is referred. Although the direct relation of cartilage lesions, especially chondral, and pain is a subject of debate these lesions may be responsible of early osteoarthrosis and can determine athlete's prognosis. The anatomy and biomechanics of patellofemoral joint is complex and symptoms are often unspecific. Transient patellar dislocation has MR distinct features that provide evidence of prior dislocation and rules our complication. However, anterior knee pain more often is related to overuse and repeated minor trauma. Patella and quadriceps tendon have been also implicated in anterior knee pain, as well as lateral or medial restraint structures and Hoffa's pad. US and MR are excellent tools for the diagnosis of superficial tendons, the advantage of MR is that permits to rule out other sources of intraarticular derangements. Due to the complex anatomy and biomechanic of patellofemoral joint maltracking is not fully understood; plain films and CT allow the study of malalignment, new CT and MR kinematic studies have promising results but further studies are needed. Our purpose here is to describe how imaging techniques can be helpful in precisely defining the origin of the patient's complaint and thus improve understanding and management of these injuries.

  20. [Pathogenesis of knee osteoarthrist].

    PubMed

    Bennemann, M; Hönle, W; Simank, H G; Schuh, A

    2007-06-21

    More than 20% of the population of over 60-year olds suffers from degenerative joint diseases of the lower extremities. The cause of primary osteoarthritis of the knee is still unknown. A multifactorial genesis is presumed that includes genetic, nutritional, hormonal and age-related factors. On the other hand, secondary osteoarthritis is a sequela of predisposing factors. The most frequent are axial deformities, pre-existing conditions or injuries. Pre-osteoarthritis appears as dysplasias and dystopias (abnormal presentation) of the patella and axial misalignments, incongruities and joint damage after fractures. The result is the mechanical destruction of the cartilage that, in turn, initiates a vicious circle of further cartilage loss.

  1. Prosthetic knee design by simulation

    SciTech Connect

    Hollerbach, K; Hollister, A

    1999-07-30

    Although 150,000 total knee replacement surgeries are performed annually in North America, current designs of knee prostheses have mechanical problems that include a limited range of motion, abnormal gait patterns, patellofemoral joint dysfunction, implant loosening or subsidence, and excessive wear. These problems fall into three categories: failure to reproduce normal joint kinematics, which results in altered limb function; bone-implant interface failure; and material failure. Modern computer technology can be used to design, prototype, and test new total knee implants. The design team uses the full range of CAD-CAM to design and produce implant prototypes for mechanical and clinical testing. Closer approximation of natural knee kinematics and kinetics is essential for improved patient function and diminished implant loads. Current knee replacement designs are based on 19th Century theories that the knee moves about a variable axis of rotation. Recent research has shown, however, that knee motion occurs about two fixed, offset axes of rotation. These aces are not perpendicular to the long axes of the bones or to each other, and the axes do not intersect. Bearing surfaces of mechanisms that move about axes of rotation are surfaces of revolution of those axes which advanced CAD technology can produce. Solids with surfaces of revolution for the two axes of rotation for the knee have been made using an HP9000 workstation and Structural Ideas Master Series CAD software at ArthroMotion. The implant's CAD model should closely replicate movements of the normal knee. The knee model will have a range of flexion-extension (FE) from -5 to 120 degrees. Movements include varus, valgus, internal and external rotation, as well as flexion and extension. The patellofemoral joint is aligned perpendicular to the FE axis and replicates the natural joint more closely than those of existing prostheses. The bearing surfaces will be more congruent than current designs and should

  2. 49 CFR 572.166 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Knees and knee impact test procedure. 572.166... Hybrid III Six-Year-Old Weighted Child Test Dummy § 572.166 Knees and knee impact test procedure. The knee assembly is assembled and tested as specified in 49 CFR 572.126 (Subpart N)....

  3. 49 CFR 572.166 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Knees and knee impact test procedure. 572.166... Hybrid III Six-Year-Old Weighted Child Test Dummy § 572.166 Knees and knee impact test procedure. The knee assembly is assembled and tested as specified in 49 CFR 572.126 (Subpart N)....

  4. 21 CFR 888.3570 - Knee joint femoral (hemi-knee) metallic uncemented prosthesis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Knee joint femoral (hemi-knee) metallic uncemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3570 Knee joint femoral (hemi-knee) metallic uncemented prosthesis. (a) Identification. A knee joint femoral...

  5. 21 CFR 888.3570 - Knee joint femoral (hemi-knee) metallic uncemented prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femoral (hemi-knee) metallic uncemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3570 Knee joint femoral (hemi-knee) metallic uncemented prosthesis. (a) Identification. A knee joint femoral...

  6. 21 CFR 888.3570 - Knee joint femoral (hemi-knee) metallic uncemented prosthesis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Knee joint femoral (hemi-knee) metallic uncemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3570 Knee joint femoral (hemi-knee) metallic uncemented prosthesis. (a) Identification. A knee joint femoral...

  7. 21 CFR 888.3570 - Knee joint femoral (hemi-knee) metallic uncemented prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Knee joint femoral (hemi-knee) metallic uncemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3570 Knee joint femoral (hemi-knee) metallic uncemented prosthesis. (a) Identification. A knee joint femoral...

  8. 49 CFR 572.166 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Knees and knee impact test procedure. 572.166... Hybrid III Six-Year-Old Weighted Child Test Dummy § 572.166 Knees and knee impact test procedure. The knee assembly is assembled and tested as specified in 49 CFR 572.126 (Subpart N)....

  9. 49 CFR 572.166 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Knees and knee impact test procedure. 572.166... Hybrid III Six-Year-Old Weighted Child Test Dummy § 572.166 Knees and knee impact test procedure. The knee assembly is assembled and tested as specified in 49 CFR 572.126 (Subpart N)....

  10. 21 CFR 888.3570 - Knee joint femoral (hemi-knee) metallic uncemented prosthesis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Knee joint femoral (hemi-knee) metallic uncemented... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3570 Knee joint femoral (hemi-knee) metallic uncemented prosthesis. (a) Identification. A knee joint femoral...

  11. 49 CFR 572.166 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Knees and knee impact test procedure. 572.166... Hybrid III Six-Year-Old Weighted Child Test Dummy § 572.166 Knees and knee impact test procedure. The knee assembly is assembled and tested as specified in 49 CFR 572.126 (Subpart N)....

  12. Exercise for knee osteoarthritis.

    PubMed

    Baker, K; McAlindon, T

    2000-09-01

    Adverse outcomes in knee osteoarthritis include pain, loss of function, and disability. These outcomes can have devastating effects on the quality of life of those suffering from the disease. Treatments have generally targeted pain, assuming that disability would improve as a direct result of improvements in pain. However, there is evidence to suggest that determinants of pain and disability differ. In general, treatments have been more successful at decreasing pain rather than disability. Many of the factors that lead to disability can be improved with exercise. Exercise, both aerobic and strength training, have been examined as treatments for knee osteoarthritis, with considerable variability in the results. The variability between studies may be due to differences in study design, exercise protocols, and participants in the studies. Although there is variability among studies, it is notable that a majority of the studies had a positive effect on pain and or disability. The mechanism of exercise remains unclear and merits future studies to better define a concise, clear exercise protocol that may have the potential for a public health intervention.

  13. New Generation Lockable Knee Brace

    NASA Technical Reports Server (NTRS)

    2000-01-01

    A knee brace that uses Space Shuttle propulsion technology has moved a step closer to being available to help knee injury and stroke patients and may possibly benefit patients with birth defects, spinal cord injuries, and post-polio conditions. After years of hard work, inventors at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama, have turned over the final design and prototype to industry partners at Horton's Orthotic Lab in Little Rock, Arkansas for further clinical testing. The device, called the Selectively Lockable Knee Brace, may mean faster, less painful rehabilitation for patients by allowing the knee to move when weight is not on the heel. Devices currently on the market lock the knee in a rigid, straight-leg position, or allow continuous free motion. The knee brace is just one example of how space technology is being used to improve the lives of people on Earth. NASA's MSFC inventors Michael Shadoan and Neill Myers are space propulsion engineers who use the same mechanisms and materials to build systems for rockets that they used to design and develop the knee brace.

  14. Physiotherapy management of knee osteoarthritis.

    PubMed

    Page, Carolyn J; Hinman, Rana S; Bennell, Kim L

    2011-05-01

    Knee osteoarthritis (OA) is a prevalent chronic joint disease causing pain and disability. Physiotherapy, which encompasses a number of modalities, is a non-invasive treatment option in the management of OA. This review summarizes the evidence for commonly used physiotherapy interventions. There is strong evidence to show short-term beneficial effects of exercise on pain and function, although the type of exercise does not seem to influence treatment outcome. Delivery modes, including individual, group or home exercise are all effective, although therapist contact may improve benefits. Attention to improving adherence to exercise is needed to maximize outcomes in the longer-term. Knee taping applied with the aim of realigning the patella and unloading soft tissues can reduce pain. There is also evidence to support the use of knee braces in people with knee OA. Biomechanical studies show that lateral wedge shoe insoles reduce knee load but clinical trials do not support symptomatic benefits. Recent studies suggest individual shoe characteristics also affect knee load and there is current interest in the effect of modified shoe designs. Manual therapy, while not to be used as a stand-alone treatment, may be beneficial. In summary, although the research is not equivocal, there is sufficient evidence to indicate that physiotherapy interventions can reduce pain and improve function in those with knee OA.

  15. Immunohistochemical analysis of the neural structures of the posterior cruciate ligament in osteoarthritis patients submitted to total knee arthroplasty: an analysis of thirty-four cases

    PubMed Central

    Martins, Glaucus Cajaty; Camanho, Gilberto; Rodrigues, Mara Ibis

    2015-01-01

    OBJECTIVES: Many authors recommend posterior cruciate ligament-retaining arthroplasty with the intention to maintain the proprioception properties of this ligament. Preservation of the neuroreceptors and nervous fibers may be essential for retaining the proprioception function of the posterior cruciate ligament. The present study was thus developed to evaluate the presence of neural structures in the posterior cruciate ligament resected during posterior stabilized arthroplasty in osteoarthritis patients. In particular, clinical, radiographic and histological parameters were correlated with the presence or absence of neural structures in the posterior cruciate ligament. METHODS: In total, 34 posterior cruciate ligament specimens were stained with hematoxylin-eosin and Gomori trichrome. An immunohistochemical analysis using antibodies against the S100 protein and neurofilaments was also performed. The presence of neural structures was correlated with parameters such as tibiofemoral angulation, histological degeneration of the posterior cruciate ligament, Ahlbäck radiological classification, age, gender and the histologic pattern of the synovial neurovascular bundle around the posterior cruciate ligament. RESULTS: In total, 67.5% of the cases presented neural structures in the posterior cruciate ligament. In 65% of the cases, the neurovascular bundle was degenerated. Nervous structures were more commonly detected in varus knees than in valgus knees (77% versus 50%). Additionally, severe histologic degeneration of the posterior cruciate ligament was related to neurovascular bundle degeneration. CONCLUSIONS: Severe posterior cruciate ligament degeneration was related to neurovascular bundle compromise. Neural structures were more commonly detected in varus knees. Intrinsic neural structures were detected in the majority of the posterior cruciate ligaments of patients submitted to knee arthroplasty for osteoarthritis. PMID:25789514

  16. Anterior Knee Pain (Chondromalacia Patellae).

    ERIC Educational Resources Information Center

    Garrick, James G.

    1989-01-01

    This article presents a pragmatic approach to the definition, diagnosis, and management of anterior knee pain. Symptoms and treatment are described. Emphasis is on active involvement of the patient in the rehabilitation exercise program. (IAH)

  17. Arthroplasty of a Charcot knee

    PubMed Central

    Babazadeh, Sina; Stoney, James D.; Lim, Keith; Choong, Peter F.M.

    2010-01-01

    The Charcot knee - or neuropathic arthropathy - presents a considerable challenge to the orthopaedic surgeon. Caused by a combination of sensory, motor and autonomic neuropathy, it was originally described as an arthritic sequelae of neurosyphilis. In today's western orthopaedics it is more often caused by diabetes. A Charcot knee is often symptomatically painful and unstable. Traditional management has usually been conservative or arthrodesis, with limited success. Arthroplasty of a Charcot joint has commonly been avoided at all costs. However, in the right patient, using the right technique, arthroplasty can significantly improve the symptoms of a Charcot joint. This article explores the evidence surrounding the role of arthroplasty in the management of a Charcot knee. Arthroplasty is compared to other forms of treatment and specific patient demographics and surgical techniques are explored in an attempt to define the role of arthroplasty in the management of a Charcot knee. PMID:21808708

  18. Bowlegs and Knock-Knees

    MedlinePlus

    ... Infections Learning Disabilities Obesity Orthopedic Prevention Sexually Transmitted ... and Knock-Knees Page Content Article Body Toddlers’ legs often have a bowed appearance. In fact, many children have bowing of the ...

  19. Knee Brace Would Lock And Unlock Automatically

    NASA Technical Reports Server (NTRS)

    Myers, Neill; Forbes, John; Shadoan, Mike; Baker, Kevin

    1995-01-01

    Proposed knee brace designed to aid rehabilitation of person who suffered some muscle damage in leg. Not limited to locking in straight-leg position and, instead, locks at any bend angle. Does not prevent knee from bearing weight. Instead, knee brace allows knee to bear weight and locks only when foot and lower leg bear weight. Thus, brace prevents flexion that wearer desired to prevent but could not prevent because of weakened muscles. Knee bends freely to exercise knee-related muscles. Knee brace strapped at upper end to leg above knee, and anchored at lower end by stirrup under foot. Joint mechanism (identical mechanisms used in left and right assemblies) allows knee joint to flex freely except when weight applied to heel.

  20. [Congenital knee dislocation: case report].

    PubMed

    Arvinius, C; Luque, R; Díaz-Ceacero, C; Marco, F

    2016-01-01

    Congenital knee dislocation is an infrequent condition with unknown etiology. In some cases it occurs as an isolated condition, while in others it coexists with associated conditions or syndromes. The treatment of congenital knee dislocation is driven by the severity and flexibility of the deformity. The literature includes from serial casting or the Pavlik harness to quadriceps tendon plasty or femoral osteotomies. We report herein the case of a congenital dislocation treated with serial casting with a good outcome.

  1. Tibia valga morphology in osteoarthritic knees: importance of preoperative full limb radiographs in total knee arthroplasty.

    PubMed

    Alghamdi, Ahmed; Rahmé, Michel; Lavigne, Martin; Massé, Vincent; Vendittoli, Pascal-André

    2014-08-01

    Osteoarthritis of the knee is associated with deformities of the lower limb. Tibia valga is a contributing factor to lower limb alignment in valgus knees. We evaluated 97 valgus knees and 100 varus knees. Long-leg films were taken in weight bearing with both knees in full extension. For valgus knees, 52 knees (53%) had a tibia valga deformity. Average tibia valgus deformation was 5.0°. For varus knees, there was only 1 case of tibia valga (1%), with a deformation of 2.5°. The aim of this study was to assess the prevalence of primary tibia valga in valgus and varus knees and understand how it affects our approach to total knee arthroplasty (TKA). We recommend having full-leg length films when planning for TKA in valgus knees.

  2. Changes in knee kinematics following total knee arthroplasty.

    PubMed

    Akbari Shandiz, Mohsen; Boulos, Paul; Saevarsson, Stefan Karl; Yoo, Sam; Miller, Stephen; Anglin, Carolyn

    2016-04-01

    Total knee arthroplasty (TKA) changes the knee joint in both intentional and unintentional, known and unknown, ways. Patellofemoral and tibiofemoral kinematics play an important role in postoperative pain, function, satisfaction and revision, yet are largely unknown. Preoperative kinematics, postoperative kinematics or changes in kinematics may help identify causes of poor clinical outcome. Patellofemoral kinematics are challenging to record since the patella is obscured by the metal femoral component in X-ray and moves under the skin. The purpose of this study was to determine the kinematic degrees of freedom having significant changes and to evaluate the variability in individual changes to allow future study of patients with poor clinical outcomes. We prospectively studied the 6 degrees of freedom patellofemoral and tibiofemoral weightbearing kinematics, tibiofemoral contact points and helical axes of rotation of nine subjects before and at least 1 year after total knee arthroplasty using clinically available computed tomography and radiographic imaging systems. Normal kinematics for healthy individuals were identified from the literature. Significant differences existed between pre-TKA and post-TKA kinematics, with the post-TKA kinematics being closer to normal. While on average the pre-total knee arthroplasty knees in this group displayed no pivoting (only translation), individually only five knees displayed this behaviour (of these, two showed lateral pivoting, one showed medial pivoting and one showed central pivoting). There was considerable variability postoperatively as well (five central, two lateral and two medial pivoting). Both preop and postop, flexion behaviour was more hinge-like medially and more rolling laterally. Helical axes were more consistent postop for this group. An inclusive understanding of the pre-TKA and post-TKA kinematics and changes in kinematics due to total knee arthroplasty could improve implant design, patient diagnosis and

  3. MRI of knee ligament injury and reconstruction.

    PubMed

    Farshad-Amacker, Nadja A; Potter, Hollis G

    2013-10-01

    Knee ligament instability may lead to meniscal and chondral damage, resulting in early osteoarthritis. Due to its superior soft tissue contrast and avoidance of harmful ionizing radiation, MRI has become the most important imaging modality for early recognition of structural defects of the knee joint. This review aims to the understanding of MRI appearances of knee ligament structures associated with knee instability, and to review the common patterns of altered knee mechanics that lead to ligament failure. Normal anatomy of the knee ligaments, pathologic conditions, and postsurgical appearances of the anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament, and posterolateral corner are described.

  4. Medial unicondylar knee arthroplasty: technical pearls

    PubMed Central

    BONIFORTI, FILIPPO

    2015-01-01

    Unicondylar knee arthroplasty implantation is extremely demanding as the prosthesis needs to be integrated in the natural anatomy of the knee. It ensures the integrity of the natural knee kinematic. Some studies and registries data have shown lower success rate in comparison with total knee arthroplasty, and patient-related factors may have an impact on outcome. While, better results have been published by high volume centres. The indications for surgery should be reconsidered critically, even if medial osteoarthritis of the knee remains the most common. This article sets out the diagnostic, and surgical steps in order to fine tuning the unicompartmental replacement of the knee. PMID:26605256

  5. Intraoperative passive knee kinematics during total knee arthroplasty surgery.

    PubMed

    Young, Kathryn L; Dunbar, Michael J; Richardson, Glen; Astephen Wilson, Janie L

    2015-11-01

    Surgical navigation systems for total knee arthroplasty (TKA) surgery are capable of capturing passive three-dimensional (3D) angular joint movement patterns intraoperatively. Improved understanding of patient-specific knee kinematic changes between pre and post-implant states and their relationship with post-operative function may be important in optimizing TKA outcomes. However, a comprehensive characterization of the variability among patients has yet to be investigated. The objective of this study was to characterize the variability within frontal plane joint movement patterns intraoperatively during a passive knee flexion exercise. Three hundred and forty patients with severe knee osteoarthritis (OA) received a primary TKA using a navigation system. Passive kinematics were captured prior to (pre-implant), and after prosthesis insertion (post-implant). Principal component analysis (PCA) was used to capture characteristic patterns of knee angle kinematics among patients, to identify potential patient subgroups based on these patterns, and to examine the subgroup-specific changes in these patterns between pre- and post-implant states. The first four extracted patterns explained 99.9% of the diversity within the frontal plane angle patterns among the patients. Post-implant, the magnitude of the frontal plane angle shifted toward a neutral mechanical axis in all phenotypes, yet subtle pattern (shape of curvature) features of the pre-implant state persisted.

  6. Anterior knee pain after total knee arthroplasty: a narrative review.

    PubMed

    Petersen, Wolf; Rembitzki, Ingo Volker; Brüggemann, Gerd-Peter; Ellermann, Andree; Best, Raymond; Koppenburg, Andreas Gösele-; Liebau, Christian

    2014-02-01

    Anterior knee pain is one of the most common causes of persistent problems after implantation of a total knee replacement. It can occur in patients with or without patellar resurfacing. As a result of the surgical procedure itself many changes can occur which may affect the delicate interplay of the joint partners in the patello-femoral joint. Functional causes of anterior knee pain can be distinguished from mechanical causes. The functional causes concern disorders of inter- and intramuscular coordination, which can be attributed to preoperative osteoarthritis. Research about anterior knee pain has shown that not only the thigh muscles but also the hip and trunk stabilising muscles may be responsible for the development of a dynamic valgus malalignment. Dynamic valgus may be a causative factor for patellar maltracking. The mechanical causes of patello-femoral problems after knee replacement can be distinguished according to whether they increase instability in the joint, increase joint pressure or whether they affect the muscular lever arms. These causes include offset errors, oversizing, rotational errors of femoral or tibial component, instability, maltracking and chondrolysis, patella baja and aseptic loosening. In these cases, reoperation or revision is often necessary.

  7. Matching "The Carnival of the Animals" to Drawings with Children 6-9 Years Old in England, Japan, Korea, Spain, and the United States.

    ERIC Educational Resources Information Center

    Moore, Randall; Cutler, Joan E.; Mito, Hiromichi; Auh, Myung-Sook; Brotons, Melissa

    1999-01-01

    Investigates how accurately children, ages 6-9 from England, Japan, Korea, Spain, and the United States, could match eight animal drawings to excerpts from the well-known concert music, "The Carnival of the Animals" by Charles Camille Saint-Saens. Indicates a mean correct response of 40% without instruction. Discusses two extension…

  8. Effects of English Cued Speech on Speech Perception, Phonological Awareness and Literacy: A Case Study of a 9-Year-Old Deaf Boy Using a Cochlear Implant

    ERIC Educational Resources Information Center

    Rees, Rachel; Bladel, Judith

    2013-01-01

    Many studies have shown that French Cued Speech (CS) can enhance lipreading and the development of phonological awareness and literacy in deaf children but, as yet, there is little evidence that these findings can be generalized to English CS. This study investigated the possible effects of English CS on the speech perception, phonological…

  9. Ritual circumcision and risk of autism spectrum disorder in 0- to 9-year-old boys: national cohort study in Denmark

    PubMed Central

    Simonsen, Jacob

    2015-01-01

    Objective Based on converging observations in animal, clinical and ecological studies, we hypothesised a possible impact of ritual circumcision on the subsequent risk of autism spectrum disorder (ASD) in young boys. Design National, register-based cohort study. Setting Denmark. Participants A total of 342,877 boys born between 1994 and 2003 and followed in the age span 0–9 years between 1994 and 2013. Main outcome measures Information about cohort members’ ritual circumcisions, confounders and ASD outcomes, as well as two supplementary outcomes, hyperkinetic disorder and asthma, was obtained from national registers. Hazard ratios (HRs) with 95% confidence intervals (CIs) associated with foreskin status were obtained using Cox proportional hazards regression analyses. Results With a total of 4986 ASD cases, our study showed that regardless of cultural background circumcised boys were more likely than intact boys to develop ASD before age 10 years (HR = 1.46; 95% CI: 1.11–1.93). Risk was particularly high for infantile autism before age five years (HR = 2.06; 95% CI: 1.36–3.13). Circumcised boys in non-Muslim families were also more likely to develop hyperkinetic disorder (HR = 1.81; 95% CI: 1.11–2.96). Associations with asthma were consistently inconspicuous (HR = 0.96; 95% CI: 0.84–1.10). Conclusions We confirmed our hypothesis that boys who undergo ritual circumcision may run a greater risk of developing ASD. This finding, and the unexpected observation of an increased risk of hyperactivity disorder among circumcised boys in non-Muslim families, need attention, particularly because data limitations most likely rendered our HR estimates conservative. Considering the widespread practice of non-therapeutic circumcision in infancy and childhood around the world, confirmatory studies should be given priority. PMID:25573114

  10. Autistic Features in a Total Population of 7-9-Year-Old Children Assessed by the ASSQ (Autism Spectrum Screening Questionnaire)

    ERIC Educational Resources Information Center

    Posserud, Maj-Britt; Lundervold, Astri J.; Gillberg, Christopher

    2006-01-01

    Background: The prevalence of autism is reported to be on the rise worldwide. Change of diagnostic criteria and a broadening of the concept of autism have been mentioned as contributing factors. Further studies of general populations are needed. The present study assessed the distribution of autistic features in a total population of children 7-9…

  11. Omega 3/6 Fatty Acids for Reading in Children: A Randomized, Double-Blind, Placebo-Controlled Trial in 9-Year-Old Mainstream Schoolchildren in Sweden

    ERIC Educational Resources Information Center

    Johnson, Mats; Fransson, Gunnar; Östlund, Sven; Areskoug, Björn; Gillberg, Christopher

    2017-01-01

    Background: Previous research has shown positive effects of Omega 3/6 fatty acids in children with inattention and reading difficulties. We aimed to investigate if Omega 3/6 improved reading ability in mainstream schoolchildren. Methods: We performed a 3-month parallel, randomized, double-blind, placebo-controlled trial followed by 3-month active…

  12. Preterm born 9-year-olds have elevated IGF-1 and low prolactin, but levels vary with behavioural and eating disorders

    PubMed Central

    Kistner, A; Deschmann, E; Legnevall, L; Vanpee, M

    2014-01-01

    Aim This study examined the relationship between hypothalamic-associated hormones and behavioural and eating disorders in children with low birthweight. Methods We included 100 children (mean age 9.7 years): 39 were born preterm at <32 gestational weeks, 28 were full-term, but small for gestational age, and 33 were full-term controls. Behavioural histories were analysed, together with fasting blood samples of leptin, insulin, insulin-like growth factor-1 (IGF-I), prolactin, glucagon and cortisol. Results Preterm children had lower prolactin (p = 0.01) and higher IGF-I than controls (p < 0.05, adjusted for confounders), despite being significantly shorter than the predicted target height (p < 0.001). More preterm children displayed behavioural disorders (38% versus 10%, p < 0.001) and eating disorders (26% versus 8%, p < 0.05) than full-term children. These disorders were associated with lower leptin (p < 0.01), insulin (p < 0.05) and IGF-I (p < 0.05), but correlations between these hormones and leptin were similar among the groups. Combined behavioural and eating disorders were only observed in preterm children, who were also the shortest in height. Conclusion Behavioural and eating disorders among preterm children were associated with low leptin, insulin and IGF-1. Low prolactin in all preterm children indicated an increased dopaminergic tonus, which might inhibit body weight incrementation. This raises speculation about IGF-I receptor insensitivity. PMID:25040495

  13. A Comparison of the Motor Ability of 8 and 9 Year Old Primary School Children in Hamburg, Melbourne and Cape Town--An Exploratory Study

    ERIC Educational Resources Information Center

    Kretschmer, Jurgen; Saunders, John; Bressan, Liz; Erhorn, Jan; Wirszing, Daniel

    2013-01-01

    An increasing worldwide concern about a decline in the quality of the motor ability of children was the motivation for this exploratory comparative study. It involves a comparison of the motor ability of children aged 8 and 9 years from Hamburg (n = 774), Melbourne (n = 141) and Cape Town (n = 81). Since each of these global cities represents a…

  14. Children's Cognitive Ability from 4 to 9 Years Old as a Function of Prenatal Cocaine Exposure, Environmental Risk, and Maternal Verbal Intelligence

    ERIC Educational Resources Information Center

    Bennett, David S.; Bendersky, Margaret; Lewis, Michael

    2008-01-01

    This study examined the effects of prenatal cocaine exposure, environmental risk, and maternal verbal intelligence on children's cognitive ability. Gender and age were examined as moderators of potential cocaine exposure effects. The Stanford-Binet IV intelligence test was administered to 231 children (91 cocaine exposed, 140 unexposed) at ages 4,…

  15. A study on nutritional status and tooth crown size among 6–9-year-old children: An observational cross-sectional study

    PubMed Central

    Zameer, Mohammed; Basheer, Syed Nahid; Anwar, Naviwala Gulam; Mudassar, Mohammed; Reddy, Arun; Quadri, Haroon

    2016-01-01

    Background: Numerous factors contribute to variation in tooth size. This is broadly described as genetic, epigenetic, and environmental factors. A strong genetic contribution has been shown, but environmental factors may also play a role. Aim: The aim of this study was to determine the relationship between nutritional status and tooth crown size. Design: An observational cross-sectional survey was conducted among 100 school-going children of 6–9 years. The value obtained was plotted on age- and gender-specific percentile curves chart given by the Centers for Disease Control and Prevention; individuals were categorized based on body mass index criteria. The participants were examined for the mesiodistal width of primary second molar and permanent first molar by three different observers using a Vernier Caliper. Data obtained were statistically analyzed. Results: total of 45, 40, and 15 belonged to underweight, normal, and overweight category, respectively. The tooth size of primary molar between healthy, overweight, and underweight children was 9.87 ± 0.23, 9.47 ± 0.48, and 9.61 ± 0.7, respectively, and for permanent molar between healthy, overweight, and underweight children was 10.63 ± 0.2, 10.56 ± 0.5, and 10.57 ± 0.6, respectively. Conclusion: The correlation between tooth crown size with an exogenous chronic stressor, i.e., malnutrition, was found to be nonsignificant when compared with the healthy individuals. The findings indicate that nutritional status does not significantly influence the determination of tooth size in humans. PMID:28123266

  16. Understanding Expressive Speech Acts: The Role of Prosody and Situational Context in French-Speaking 5- to 9-Year-Olds

    ERIC Educational Resources Information Center

    Aguert, Marc; Laval, Virginie; Le Bigot, Ludovic; Bernicot, Josie

    2010-01-01

    Purpose: This study was aimed at determining the role of prosody and situational context in children's understanding of expressive utterances. Which one of these 2 cues will help children grasp the speaker's intention? Do children exhibit a "contextual bias" whereby they ignore prosody, such as the "lexical bias" found in other studies (M. Friend…

  17. Psychological and Physiological Processes in Figure-Tracing Abilities Measured Using a Tablet Computer: A Study with 7 and 9 Years Old Children

    PubMed Central

    Giammarco, Enrico; Di Sano, Sergio; Aureli, Tiziana; Cerratti, Paola; Fanò-Illic, Giorgio; Pietrangelo, Tiziana

    2016-01-01

    The present study investigated the use of a tablet computer to assess figure-tracing skills and their relationships with psychological (visual–perceptual processes, cognitive processes, handwriting skills) and physiological (body mass index, isometric strength of arms) parameters with school-children of second (7–8-year-olds) and fourth (9–10-year-olds) grades. We were also interested in gender differences. The task required tracing of geometric figures on a template, shown on a tablet screen in light gray, for the segments that make up the target figure, one at a time. This figure-tracing tablet test allows acquisition and automated analysis of four parameters: number of strokes (pen lift) for each segment; oscillations of lines drawn with respect to reference lines; pressure of pen on tablet; and average speed of tracing. The results show a trade-off between speed and quality for the tablet parameters, with higher speed associated with more oscillations with respect to the reference lines, and lower number of strokes for each segment, in both male and female children. The involvement of visual–motor integration on the ability to reduce the oscillations in this tablet test was only seen for the male children, while both the male and female children showed a relationship between oscillations and more general/abstract visual–spatial processes. These data confirm the role of visual–motor processes in this figure-tracing tablet test only for male children, while more general visual–spatial processes influence the performance in the tablet test for both sexes. We conclude that the test proposed is useful to screen for grapho-motor difficulties. PMID:27803678

  18. How to Measure Qualitative Understanding of DC-Circuit Phenomena--Taking a Closer Look at the External Representations of 9-Year-Olds

    ERIC Educational Resources Information Center

    Kallunki, Veera

    2013-01-01

    Pupils' qualitative understanding of DC-circuit phenomena is reported to be weak. In numerous research reports lists of problems in understanding the functioning of simple DC-circuits have been presented. So-called mental model surveys have uncovered difficulties in different age groups, and in different phases of instruction. In this study, the…

  19. Do Challenge, Task Experience or Computer Familiarity Influence the Learning of Historical Chronology from Virtual Environments in 8-9 Year Old Children?

    ERIC Educational Resources Information Center

    Korallo, Liliya; Foreman, Nigel; Boyd-Davis, Stephen; Moar, Magnus; Coulson, Mark

    2012-01-01

    Studies examined the potential use of VEs in teaching historical chronology to 127 children of primary school age (8-9 years). The use of passive fly-through VEs had been found, in an earlier study, to be disadvantageous with this age group when tested for their subsequent ability to place displayed sequential events in correct chronological…

  20. Comparison of knee gait kinematics of workers exposed to knee straining posture to those of non-knee straining workers.

    PubMed

    Gaudreault, Nathaly; Hagemeister, Nicola; Poitras, Stéphane; de Guise, Jacques A

    2013-06-01

    Workers exposed to knee straining postures, such as kneeling and squatting, may present modifications in knee gait kinematics that can make them vulnerable to osteoarthritis. In this study, knee kinematics of workers exposed to occupational knee straining postures (KS workers) were compared to those of non-knee straining (non-KS) workers. Eighteen KS workers and 20 non-KS workers participated in the study. Three-dimensional gait kinematic data were recorded at the knee using an electromagnetic motion tracking system. The following parameters were extracted from flexion/extension, adduction/abduction and internal/external rotation angle data and used for group comparisons: knee angle at initial foot contact, peak angles, minimal angles and angle range during the entire gait cycle. Group comparisons were performed with Student t-tests. In the sagittal plane, KS workers had a greater knee flexion angle at initial foot contact, a lower peak knee flexion angle during the swing phase and a lower angle range than non-KS workers (p<0.05). In the frontal plane, all parameters indicated that KS workers had their knees more adducted than non-KS workers. External/internal rotation range was greater for KS workers. This study provides new knowledge on work related to KS postures and knee kinematics. The results support the concept that KS workers might exhibit knee kinematics that are different from those of non-KS workers.

  1. Predicting Knee Osteoarthritis.

    PubMed

    Gardiner, Bruce S; Woodhouse, Francis G; Besier, Thor F; Grodzinsky, Alan J; Lloyd, David G; Zhang, Lihai; Smith, David W

    2016-01-01

    Treatment options for osteoarthritis (OA) beyond pain relief or total knee replacement are very limited. Because of this, attention has shifted to identifying which factors increase the risk of OA in vulnerable populations in order to be able to give recommendations to delay disease onset or to slow disease progression. The gold standard is then to use principles of risk management, first to provide subject-specific estimates of risk and then to find ways of reducing that risk. Population studies of OA risk based on statistical associations do not provide such individually tailored information. Here we argue that mechanistic models of cartilage tissue maintenance and damage coupled to statistical models incorporating model uncertainty, united within the framework of structural reliability analysis, provide an avenue for bridging the disciplines of epidemiology, cell biology, genetics and biomechanics. Such models promise subject-specific OA risk assessment and personalized strategies for mitigating or even avoiding OA. We illustrate the proposed approach with a simple model of cartilage extracellular matrix synthesis and loss regulated by daily physical activity.

  2. Knee Replacement: MedlinePlus Health Topic

    MedlinePlus

    ... Arthritis and Musculoskeletal and Skin Diseases) Also in Spanish Knee Replacement (Mayo Foundation for Medical Education and ... American Academy of Orthopaedic Surgeons) - PDF Also in Spanish Total Knee Replacement (Arthroplasty) (Beyond the Basics) (UpToDate) ...

  3. [What's new about total knee arthroplasty].

    PubMed

    Dao Trong, Mai Lang; Helmy, Näder

    2013-10-30

    Osteoarthritis of the knee is one of the most common problems in the orthopedic practice and its surgical technique is still challenging. This Mini-Review presents patient specific cutting blocks for the implantation of a total knee arthroplasty.

  4. Knee joint forces: prediction, measurement, and significance

    PubMed Central

    D’Lima, Darryl D.; Fregly, Benjamin J.; Patil, Shantanu; Steklov, Nikolai; Colwell, Clifford W.

    2011-01-01

    Knee forces are highly significant in osteoarthritis and in the survival and function of knee arthroplasty. A large number of studies have attempted to estimate forces around the knee during various activities. Several approaches have been used to relate knee kinematics and external forces to internal joint contact forces, the most popular being inverse dynamics, forward dynamics, and static body analyses. Knee forces have also been measured in vivo after knee arthroplasty, which serves as valuable validation of computational predictions. This review summarizes the results of published studies that measured knee forces for various activities. The efficacy of various methods to alter knee force distribution, such as gait modification, orthotics, walking aids, and custom treadmills are analyzed. Current gaps in our knowledge are identified and directions for future research in this area are outlined. PMID:22468461

  5. Automatically Locking/Unlocking Orthotic Knee Joint

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce

    1994-01-01

    Proposed orthotic knee joint locks and unlocks automatically, at any position within range of bend angles, without manual intervention by wearer. Includes tang and clevis, locks whenever wearer transfers weight to knee and unlocks when weight removed. Locking occurs at any angle between 45 degrees knee bend and full extension.

  6. Knee Replacement - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Knee Replacement (Arabic) العربية Bilingual PDF Health Information Translations Bosnian (Bosanski) Total Knee Replacement Potpuna zamjena koljena - Bosanski (Bosnian) Bilingual PDF Health Information Translations Chinese - Simplified (简体中文) Total Knee Replacement 全膝关节置换 - 简体中文 ( ...

  7. Effect of exercise and gait retraining on knee adduction moment in people with knee osteoarthritis.

    PubMed

    Khalaj, Nafiseh; Abu Osman, Noor A; Mokhtar, Abdul H; Mehdikhani, Mahboobeh; Wan Abas, Wan A B

    2014-02-01

    The knee adduction moment represents the medial knee joint load, and greater value is associated with higher load. In people with knee osteoarthritis, it is important to apply proper treatment with the least side effects to reduce knee adduction moment and, consequently, reduce medial knee joint load. This reduction may slow the progression of knee osteoarthritis. The research team performed a literature search of electronic databases. The search keywords were as follows: knee osteoarthritis, knee adduction moment, exercise program, exercise therapy, gait retraining, gait modification and knee joint loading. In total, 12 studies were selected, according to the selection criteria. Findings from previous studies illustrated that exercise and gait retraining programs could alter knee adduction moment in people with knee osteoarthritis. These treatments are noninvasive and nonpharmacological which so far have no or few side effects, as well as being low cost. The results of this review revealed that gait retraining programs were helpful in reducing the knee adduction moment. In contrast, not all the exercise programs were beneficial in reducing knee adduction moment. Future studies are needed to indicate best clinical exercise and gait retraining programs, which are most effective in reducing knee adduction moment in people with knee osteoarthritis.

  8. Intraoperative passive kinematics of osteoarthritic knees before and after total knee arthroplasty.

    PubMed

    Siston, Robert A; Giori, Nicholas J; Goodman, Stuart B; Delp, Scott L

    2006-08-01

    Total knee arthroplasty is a successful procedure to treat pain and functional disability due to osteoarthritis. However, precisely how a total knee arthroplasty changes the kinematics of an osteoarthritic knee is unknown. We used a surgical navigation system to measure normal passive kinematics from 7 embalmed cadaver lower extremities and in vivo intraoperative passive kinematics on 17 patients undergoing primary total knee arthroplasty to address two questions: How do the kinematics of knees with advanced osteoarthritis differ from normal knees?; and, Does posterior substituting total knee arthroplasty restore kinematics towards normal? Osteoarthritic knees displayed a decreased screw-home motion and abnormal varus/valgus rotations between 10 degrees and 90 degrees of knee flexion when compared to normal knees. The anterior-posterior motion of the femur in osteoarthritic knees was not different than in normal knees. Following total knee arthroplasty, we found abnormal varus/valgus rotations in early flexion, a reduced screw-home motion when compared to the osteoarthritic knees, and an abnormal anterior translation of the femur during the first 60 degrees of flexion. Posterior substituting total knee arthroplasty does not appear to restore normal passive varus/valgus rotations or the screw motion and introduces an abnormal anterior translation of the femur during intraoperative evaluation.

  9. Early osteoarthritis of the knee.

    PubMed

    Madry, Henning; Kon, Elizaveta; Condello, Vincenzo; Peretti, Giuseppe M; Steinwachs, Matthias; Seil, Romain; Berruto, Massimo; Engebretsen, Lars; Filardo, Giuseppe; Angele, Peter

    2016-06-01

    There is an increasing awareness on the importance in identifying early phases of the degenerative processes in knee osteoarthritis (OA), the crucial period of the disease when there might still be the possibility to initiate treatments preventing its progression. Early OA may show a diffuse and ill-defined involvement, but also originate in the cartilage surrounding a focal lesion, thus necessitating a separate assessment of these two entities. Early OA can be considered to include a maximal involvement of 50 % of the cartilage thickness based on the macroscopic ICRS classification, reflecting an OARSI grade 4. The purpose of this paper was to provide an updated review of the current status of the diagnosis and definition of early knee OA, including the clinical, radiographical, histological, MRI, and arthroscopic definitions and biomarkers. Based on current evidence, practical classification criteria are presented. As new insights and technologies become available, they will further evolve to better define and treat early knee OA.

  10. [Rehabilitation after total knee arthroplasty of hip and knee].

    PubMed

    Jansen, E; Brienza, S; Gierasimowicz-Fontana, A; Matos, C; Reynders-Frederix-Dobre, C; HateM, S M

    2015-09-01

    Numbers of total hip and knee arthroplasties are increasing on a regular basis. Clinical pathways tend to shorten the duration of hospitalization in acute care after surgery. Therefore, the preoperative preparation of the patient and his abilities for postoperative rehabilitation should be carefully addressed. Before the surgical intervention, it is recommended that the patient receives an educational program and a physical preparation. After the surgical intervention, the patient can benefit from a home-based rehabilitation program supervised by a physiotherapist, if there were no preoperative reasons for prolonging the hospital stay and if the surgery took place without complications. Some patients may benefit from postsurgical rehabilitation in a specialized locomotor rehabilitation long-stay care unit. The indications for inpatient multidisciplinary rehabilitation are : two simultaneous arthroplasties, revision of a previous hip or knee arthroplasty, postsurgical complications, advanced age, comorbidities influencing the rehabilitation process, social difficulties, necessity for adaptation of the environment, insufficient or unadapted out-patient (para)medical care. The goals of the rehabilitation treatment depend on the patient's characteristics and environment, on the properties of the prosthesis and on the postsurgical complications. The functional prognosis of a total joint arthroplasty of the knee or hip is excellent, provided that there are no post-surgical complications and that the patient benefits from adequate rehabilitation therapy. The present paper describes the different phases of rehabilitation treatment and the general and specific complications of total hip and knee arthroplasties that may influence the rehabilitation outcome.

  11. Basic knee arthroscopy part 3: diagnostic arthroscopy.

    PubMed

    Ward, Benjamin D; Lubowitz, James H

    2013-11-01

    Knee arthroscopy is an important diagnostic and therapeutic tool in the management of disorders of the knee. In a series of 4 articles, the basics of knee arthroscopy are reviewed. In this article (part 3), step-by-step diagnostic arthroscopy is reviewed. Diagnostic arthroscopy is a crucial skill for diagnosing intra-articular disorders of the knee including meniscal, synovial, ligamentous, and articular cartilage pathology. Mastery of the basic diagnostic arthroscopy is a critical tool for orthopaedic surgeons treating disorders of the knee.

  12. Basic Knee Arthroscopy Part 1: Patient Positioning

    PubMed Central

    Ward, Benjamin D.; Lubowitz, James H.

    2013-01-01

    Knee arthroscopy is an important diagnostic and therapeutic tool in the management of disorders of the knee. In a series of 4 articles, the basics of knee arthroscopy are reviewed. In this article (part 1), patient positioning, tourniquet placement, and draping are reviewed. Meticulous attention to these details allows surgical access to the compartments of the knee. A circumferential leg holder or a lateral post allows the application of varus and valgus forces to open the medial and lateral compartments of the knee. PMID:24892015

  13. Knee extension torque variability after exercise in ACL reconstructed knees.

    PubMed

    Goetschius, John; Kuenze, Christopher M; Hart, Joseph M

    2015-08-01

    The purpose of this study was to compare knee extension torque variability in patients with ACL reconstructed knees before and after exercise. Thirty two patients with an ACL reconstructed knee (ACL-R group) and 32 healthy controls (control group) completed measures of maximal isometric knee extension torque (90° flexion) at baseline and following a 30-min exercise protocol (post-exercise). Exercise included 30-min of repeated cycles of inclined treadmill walking and hopping tasks. Dependent variables were the coefficient of variation (CV) and raw-change in CV (ΔCV): CV = (torque standard deviation/torque mean x 100), ΔCV = (post-exercise - baseline). There was a group-by-time interaction (p = 0.03) on CV. The ACL-R group demonstrated greater CV than the control group at baseline (ACL-R = 1.07 ± 0.55, control = 0.79 ± 0.42, p = 0.03) and post-exercise (ACL-R = 1.60 ± 0.91, control = 0.94 ± 0.41, p = 0.001). ΔCV was greater (p = 0.03) in the ACL-R group (0.52 ± 0.82) than control group (0.15 ± 0.46). CV significantly increased from baseline to post-exercise (p = 0.001) in the ACL-R group, while the control group did not (p = 0.06). The ACL-R group demonstrated greater knee extension torque variability than the control group. Exercise increased torque variability more in the ACL-R group than control group.

  14. Complex function of the knee joint: the current understanding of the knee.

    PubMed

    Hirschmann, Michael T; Müller, Werner

    2015-10-01

    Since the early years of orthopaedics, it is a well-known fact that anatomy follows function. During the evolution of mankind, the knee has been optimally adapted to the forces and loads acting at and through the knee joint. However, anatomy of the knee joint is variable and the only constant is its complex function. In contrast to the time of open surgery, nowadays the majority of reconstructive knee surgery is done arthroscopically. Keyhole surgery is less invasive, but on the backside, the knee surgeon lacks daily visualisation of the complex open anatomy. As open anatomical knowledge is less present in our daily practice, it is even more important to highlight this complex anatomy and function of the knee. It is the purpose of this review to perform a systematic review of knee anatomy, highlight the complex function of the knee joint and present an overview about recent and current knowledge about knee function. Level of evidence Systematic review, Level IV.

  15. Can generic knee joint models improve the measurement of osteoarthritic knee kinematics during squatting activity?

    PubMed

    Clément, Julien; Dumas, Raphaël; Hagemeister, Nicola; de Guise, Jaques A

    2017-01-01

    Knee joint kinematics derived from multi-body optimisation (MBO) still requires evaluation. The objective of this study was to corroborate model-derived kinematics of osteoarthritic knees obtained using four generic knee joint models used in musculoskeletal modelling - spherical, hinge, degree-of-freedom coupling curves and parallel mechanism - against reference knee kinematics measured by stereo-radiography. Root mean square errors ranged from 0.7° to 23.4° for knee rotations and from 0.6 to 9.0 mm for knee displacements. Model-derived knee kinematics computed from generic knee joint models was inaccurate. Future developments and experiments should improve the reliability of osteoarthritic knee models in MBO and musculoskeletal modelling.

  16. Biomechanics of knee joint — A review

    NASA Astrophysics Data System (ADS)

    Madeti, Bhaskar Kumar; Chalamalasetti, Srinivasa Rao; Bolla Pragada, S. K. Sundara siva rao

    2015-06-01

    The present paper is to know how the work is carried out in the field of biomechanics of knee. Various model formulations are discussed and further classified into mathematical model, two-dimensional model and three-dimensional model. Knee geometry is a crucial part of human body movement, in which how various views of knee is shown in different planes and how the forces act on tibia and femur are studied. It leads to know the forces acting on the knee joint. Experimental studies of knee geometry and forces acting on knee shown by various researchers have been discussed, and comparisons of results are made. In addition, static and dynamic analysis of knee has been also discussed respectively to some extent.

  17. Immediate effect of Masai Barefoot Technology shoes on knee joint moments in women with knee osteoarthritis.

    PubMed

    Tateuchi, Hiroshige; Taniguchi, Masashi; Takagi, Yui; Goto, Yusuke; Otsuka, Naoki; Koyama, Yumiko; Kobayashi, Masashi; Ichihashi, Noriaki

    2014-01-01

    Footwear modification can beneficially alter knee loading in patients with knee osteoarthritis. This study evaluated the effect of Masai Barefoot Technology shoes on reductions in external knee moments in patients with knee osteoarthritis. Three-dimensional motion analysis was used to examine the effect of Masai Barefoot Technology versus control shoes on the knee adduction and flexion moments in 17 women (mean age, 63.6 years) with radiographically confirmed knee osteoarthritis. The lateral and anterior trunk lean values, knee flexion and adduction angles, and ground reaction force were also evaluated. The influence of the original walking pattern on the changes in knee moments with Masai Barefoot Technology shoes was evaluated. The knee flexion moment in early stance was significantly reduced while walking with the Masai Barefoot Technology shoes (0.25±0.14Nm/kgm) as compared with walking with control shoes (0.30±0.19 Nm/kgm); whereas the knee adduction moment showed no changes. Masai Barefoot Technology shoes did not increase compensatory lateral and anterior trunk lean. The degree of knee flexion moment in the original walking pattern with control shoes was correlated directly with its reduction when wearing Masai Barefoot Technology shoes by multiple linear regression analysis (adjusted R2=0.44, P<0.01). Masai Barefoot Technology shoes reduced the knee flexion moment during walking without increasing the compensatory trunk lean and may therefore reduce external knee loading in women with knee osteoarthritis.

  18. The Meniscus-Deficient Knee

    PubMed Central

    Rao, Allison J.; Erickson, Brandon J.; Cvetanovich, Gregory L.; Yanke, Adam B.; Bach, Bernard R.; Cole, Brian J.

    2015-01-01

    Meniscal tears are the most common knee injury, and partial meniscectomies are the most common orthopaedic surgical procedure. The injured meniscus has an impaired ability to distribute load and resist tibial translation. Partial or complete loss of the meniscus promotes early development of chondromalacia and osteoarthritis. The primary goal of treatment for meniscus-deficient knees is to provide symptomatic relief, ideally to delay advanced joint space narrowing, and ultimately, joint replacement. Surgical treatments, including meniscal allograft transplantation (MAT), high tibial osteotomy (HTO), and distal femoral osteotomy (DFO), are options that attempt to decrease the loads on the articular cartilage of the meniscus-deficient compartment by replacing meniscal tissue or altering joint alignment. Clinical and biomechanical studies have reported promising outcomes for MAT, HTO, and DFO in the postmeniscectomized knee. These procedures can be performed alone or in conjunction with ligament reconstruction or chondral procedures (reparative, restorative, or reconstructive) to optimize stability and longevity of the knee. Complications can include fracture, nonunion, patella baja, compartment syndrome, infection, and deep venous thrombosis. MAT, HTO, and DFO are effective options for young patients suffering from pain and functional limitations secondary to meniscal deficiency. PMID:26779547

  19. Phaeohyphomycosis infection in the knee.

    PubMed

    Sadigursky, David; Nogueira E Ferreira, Luisa; Moreno de Oliveira Corrêa, Liz

    2016-01-01

    Phaeohyphomycosis is caused by cutaneous fungi and rarely affects large joints. This is a case report on phaeohyphomycosis in the left knee of an elderly individual without immunosuppression. It was accompanied by pain and swelling the anterior knee. The case was first suspected to be suprapatellar bursitis, and was treated with nonsteroidal anti-inflammatory drugs, without remission of symptoms. Surgical treatment was performed, with resection of the suprapatellar bursa and anterior region of the quadriceps tendon. The material was sent for anatomopathological examination and culturing. The pathological examination showed phaeohyphomycosis. The treatment instituted consisted of itraconazole, 200 mg/day for six weeks, and complete remission of symptoms was achieved. The physical examination remained normal after one year of follow-up. This is the first published case of phaeohyphomycosis infection in the suprapatellar region of the knee. Although almost all the cases reported have been associated with immunosuppressed patients, this was an exception. It is important to suspect phaeohyphomycosis in cases of knee infection, in the area of the suprapatellar bursa, when the symptoms do not resolve after clinical treatment.

  20. Dynamic splinting for knee flexion contracture following total knee arthroplasty: a case report.

    PubMed

    Finger, Eric; Willis, F Buck

    2008-12-29

    Total Knee Arthroplasty operations are increasing in frequency, and knee flexion contracture is a common pathology, both pre-existing and post-operative. A 61-year-old male presented with knee flexion contracture following a total knee arthroplasty. Physical therapy alone did not fully reduce the contracture and dynamic splinting was then prescribed for daily low-load, prolonged-duration stretch. After 28 physical therapy sessions, the active range of motion improved from -20 degrees to -12 degrees (stiff knee still lacking full extension), and after eight additional weeks with nightly wear of dynamic splint, the patient regained full knee extension, (active extension improved from -12 degrees to 0 degrees ).

  1. Posterior femoral condylar offset after total knee replacement in the risk of knee flexion contracture.

    PubMed

    Onodera, Tomohiro; Majima, Tokifumi; Nishiike, Osamu; Kasahara, Yasuhiko; Takahashi, Daisuke

    2013-08-01

    The aim of this study was to clarify the risk of knee flexion contracture associated with a posterior femoral condylar offset after total knee replacement (TKR). Radiographs from 100 healthy Japanese volunteers were included in the study. We evaluated femoral component posterior offset in various implants and compared them with the normal Japanese knee. Posterior offset of the femoral condyle is up to a maximum of 4.7 times greater than that of the healthy Japanese knee in all knee implants. Excess posterior offset of the femoral condyle in TKR prostheses may cause knee joint flexion contracture due to the relative shortening of the posterior soft tissue.

  2. Parametric modelling of a knee joint prosthesis.

    PubMed

    Khoo, L P; Goh, J C; Chow, S L

    1993-01-01

    This paper presents an approach for the establishment of a parametric model of knee joint prosthesis. Four different sizes of a commercial prosthesis are used as an example in the study. A reverse engineering technique was employed to reconstruct the prosthesis on CATIA, a CAD (computer aided design) system. Parametric models were established as a result of the analysis. Using the parametric model established and the knee data obtained from a clinical study on 21 pairs of cadaveric Asian knees, the development of a prototype prosthesis that suits a patient with a very small knee joint is presented. However, it was found that modification to certain parameters may be inevitable due to the uniqueness of the Asian knee. An avenue for rapid modelling and eventually economical production of a customized knee joint prosthesis for patients is proposed and discussed.

  3. Adjustable hinge permits movement of knee in plaster cast

    NASA Technical Reports Server (NTRS)

    Maley, W. E.

    1967-01-01

    Metal knee hinge with an adjustable sleeve worn on the outside of a leg cast facilitates movement of the knee joint. This helps eliminate stiffness of the knee and eliminates bulkiness and adjustment difficulty.

  4. Sonography of the knee joint☆

    PubMed Central

    Razek, A.A.K.A.; Fouda, N.S.; Elmetwaley, N.; Elbogdady, E.

    2009-01-01

    The aim of this article is to review the sonographic appearances of common disorders involving the knee joint. Ultrasound is a sensitive method for diagnosis of tendon injuries. Injured ligaments appear swollen with mixed echogenicity. Meniscal injuries and muscle tears can be easily diagnosed. Ultrasound shows synovial thickening and effusion in inflammatory arthropathy and erosions of the articular surface in degenerative arthritis. It can be used effectively in the detection of rheumatoid arthritic activity and for grading degenerative arthritis lesions. Cystic lesions, as well as benign and malignant soft-tissue masses, are clearly delineated. Ultrasound is a safe noninvasive imaging modality that can be used for diagnosis of different disorders involving the knee joint. PMID:23397073

  5. MRI of anterior knee pain.

    PubMed

    Samim, Mohammad; Smitaman, Edward; Lawrence, David; Moukaddam, Hicham

    2014-07-01

    Anterior knee pain is the most common knee complaint. It may be due to a variety of soft tissue or osseous abnormalities. Knowledge of the radiologic appearance of the abnormalities allows more accurate diagnosis of the cause of the pain including chondral abnormalities, patellar instability and dislocation, femoral trochlear dysplasia, abnormal patellar location, bipartite patella, various tendinopathies, bursal inflammation, traction apophysitis in pediatric and adolescent patients, and miscellaneous diseases including mediopatellar plica syndrome and Hoffa's disease. Radiographs are often obtained to exclude acute osseous abnormalities, such as fractures. Magnetic resonance (MR) imaging offers superior soft tissue contrast resolution and allows for more accurate evaluation of the underlying etiology and therefore may improve treatment and possible surgical planning.

  6. Normal anatomy and biomechanics of the knee.

    PubMed

    Flandry, Fred; Hommel, Gabriel

    2011-06-01

    Functionally, the knee comprises 2 articulations-the patellofemoral and tibiofemoral. Stability of the joint is governed by a combination of static ligaments, dynamic muscular forces, meniscocapsular aponeurosis, bony topography, and joint load. The surgeon is ill equipped to undertake surgical treatment of a dislocated knee without a sound footing in the anatomic complexities of this joint. We review the normal anatomy of the knee, emphasizing connective tissue structures and common injury patterns.

  7. A prosthetic knee using magnetorhelogical fluid damper for above-knee amputees

    NASA Astrophysics Data System (ADS)

    Park, Jinhyuk; Choi, Seung-Bok

    2015-04-01

    A prosthetic knee for above-knee (AK) amputees is categorized into two types; namely a passive and an active type. The passive prosthetic knee is generally made by elastic materials such as carbon fiber reinforced composite material, titanium and etc. The passive prosthetic knee easy to walk. But, it has disadvantages such that a knee joint motion is not similar to ordinary people. On the other hand, the active prosthetic knee can control the knee joint angle effectively because of mechanical actuator and microprocessor. The actuator should generate large damping force to support the weight of human body. But, generating the large torque using small actuator is difficult. To solve this problem, a semi-active type prosthetic knee has been researched. This paper proposes a semi-active prosthetic knee using a flow mode magneto-rheological (MR) damper for AK amputees. The proposed semi-active type prosthetic knee consists of the flow mode MR damper, hinge and prosthetic knee body. In order to support weight of human body, the required energy of MR damper is smaller than actuator of active prosthetic leg. And it can control the knee joint angle by inducing the magnetic field during the stance phase.

  8. Instability following total knee arthroplasty.

    PubMed

    Rodriguez-Merchan, E Carlos

    2011-10-01

    Background Knee prosthesis instability (KPI) is a frequent cause of failure of total knee arthroplasty. Moreover, the degree of constraint required to achieve immediate and long-term stability in total knee arthroplasty (TKA) is frequently debated. Questions This review aims to define the problem, analyze risk factors, and review strategies for prevention and treatment of KPI. Methods A PubMed (MEDLINE) search of the years 2000 to 2010 was performed using two key words: TKA and instability. One hundred and sixty-five initial articles were identified. The most important (17) articles as judged by the author were selected for this review. The main criteria for selection were that the articles addressed and provided solutions to the diagnosis and treatment of KPI. Results Patient-related risk factors predisposing to post-operative instability include deformity requiring a large surgical correction and aggressive ligament release, general or regional neuromuscular pathology, and hip or foot deformities. KPI can be prevented in most cases with appropriate selection of implants and good surgical technique. When ligament instability is anticipated post-operatively, the need for implants with a greater degree of constraint should be anticipated. In patients without significant varus or valgus malalignment and without significant flexion contracture, the posterior cruciate ligament (PCL) can be retained. However, the PCL should be sacrificed when deformity exists particularly in patients with rheumatoid arthritis, previous patellectomy, previous high tibial osteotomy or distal femoral osteotomy, and posttraumatic osteoarthritis with disruption of the PCL. In most cases, KPI requires revision surgery. Successful outcomes can only be obtained if the cause of KPI is identified and addressed. Conclusions Instability following TKA is a common cause of the need for revision. Typically, knees with deformity, rheumatoid arthritis, previous patellectomy or high tibial osteotomy, and

  9. The Swedish Knee Arthroplasty Register

    PubMed Central

    Robertsson, O.; Ranstam, J.; Sundberg, M.; W-Dahl, A.; Lidgren, L.

    2014-01-01

    We are entering a new era with governmental bodies taking an increasingly guiding role, gaining control of registries, demanding direct access with release of open public information for quality comparisons between hospitals. This review is written by physicians and scientists who have worked with the Swedish Knee Arthroplasty Register (SKAR) periodically since it began. It reviews the history of the register and describes the methods used and lessons learned. Cite this article: Bone Joint Res 2014;3:217–22. PMID:24986492

  10. Hinge total knee replacement revisited

    PubMed Central

    Cameron, Hugh U.; Hu, Cungen; Vyamont, Didier

    1997-01-01

    Objective To determine if aseptic loosening is a major problem in hinge total knee replacement. Design A cohort study. Setting A university-affiliated institute, specializing in elective orthopedic surgery. Patients Fifty-eight patients, mainly those requiring revision, in whom the conditions were such that it was felt only a totally constrained implant was appropriate. In 7 patients the implant was press-fitted; in the remainder it was cemented. Five patients required fusion or revision, and 8 died less than 2 years after implantation, leaving 45 for review. Follow-up was 2 to 13 years. Intervention Total knee replacement with a Guepar II prosthesis. Main outcome measures Radiolucency determined by the Cameron system and clinical scoring using the Hospital for Special Surgery system. Results Of the cemented components, 91% of femoral stems were type IA (no lucency), 9% were type IB (partial lucency), with no type II or III lucency. Tibial lucency was 87% type IA and 13% type IB, with no type II or III lucency. Of the noncemented components, 58% of femoral components were type IA and 42% type IB. Tibial lucency was 71% type IA and 29% type IB. Lucency was mainly present in zones 1 and 2 adjacent to the knee. Clinical rating was 18% excellent, 20% good, 20% fair and 42% poor. Postoperative complications included infection (13%), aseptic loosening (7%), quadriceps lag (16%) and extensor mechanism problems (16%). Conclusions Aseptic loosening is an uncommon problem in hinge total knee replacement. The complication rate in cases of sufficient severity as to require a hinge replacement remains high. Current indications for a hinge prosthesis are anteroposterior instability with a very large flexion gap, complete absence of the collateral ligaments and complete absence of a functioning extensor mechanism. PMID:9267296

  11. Bursae around the knee joints

    PubMed Central

    Chatra, Priyank S

    2012-01-01

    A bursa is a fluid-filled structure that is present between the skin and tendon or tendon and bone. The main function of a bursa is to reduce friction between adjacent moving structures. Bursae around the knee can be classified as those around the patella and those that occur elsewhere. In this pictorial essay we describe the most commonly encountered lesions and their MRI appearance. PMID:22623812

  12. Painful knee prosthesis: surgical approach

    PubMed Central

    Villano, Marco; Carulli, Christian; Puccini, Serena; Soderi, Stefano; Innocenti, Massimo

    2011-01-01

    Summary There are many conditions that may be responsible of a painful knee prosthesis. The possible causes are not always easily diagnosed. Common causes of prosthetic failure, such as aseptic loosening, infection, instability, progressive patellar arthropathy and recurrent synovitis are associated with clearly defined radiographic and/or clinical evidence. Prosthetic infection should always be considered first until any other cause has been demonstrated. In the presence of an infected prosthesis we carry out a two-step revision. Aseptic loosening needs implant revision more often with increasing prosthesis stability. Varus-valgus, anteroposterior, global and patello-femoral instability are failures often due to technical errors; superstabilized or constrained implants are needed depending on the instability entity. In presence of patello-femoral pain it is necessary to evaluate the stability of the patellar component and any alterations in its motion. Patellar progressive arthropathy can often cause late-onset knee pain; in this case patella resurfacing is needed. Altered patellar tracking, may need a lateral release but in some cases is related to misalignment of the components and the revision procedure is mandatory. Nevertheless, the diagnosis and treatment of a painful knee prosthesis can be extremely difficult if there is no clear evidence of any of the most common causes of failure. Referred pain, ligament and tendon dysfunction, cutaneous neuromas, synovitis, a patellar clunk have to be diagnosed and treated. A possible aetiological understimated factor is painful knee prosthesis due to metals sensibilization, in particular to nickel. In this event the quantity of nickel in the revision prosthesis must be minimal. PMID:22461812

  13. Imaging following acute knee trauma.

    PubMed

    Kijowski, R; Roemer, F; Englund, M; Tiderius, C J; Swärd, P; Frobell, R B

    2014-10-01

    Joint injury has been recognized as a potent risk factor for the onset of osteoarthritis. The vast majority of studies using imaging technology for longitudinal assessment of patients following joint injury have focused on the injured knee joint, specifically in patients with anterior cruciate ligament injury and meniscus tears where a high risk for rapid onset of post-traumatic osteoarthritis is well known. Although there are many imaging modalities under constant development, magnetic resonance (MR) imaging is the most important instrument for longitudinal monitoring after joint injury. MR imaging is sensitive for detecting early cartilage degeneration and can evaluate other joint structures including the menisci, bone marrow, tendons, and ligaments which can be sources of pain following acute injury. In this review, focusing on imaging following acute knee trauma, several studies were identified with promising short-term results of osseous and soft tissue changes after joint injury. However, studies connecting these promising short-term results to the development of osteoarthritis were limited which is likely due to the long follow-up periods needed to document the radiographic and clinical onset of the disease. Thus, it is recommended that additional high quality longitudinal studies with extended follow-up periods be performed to further investigate the long-term consequences of the early osseous and soft tissue changes identified on MR imaging after acute knee trauma.

  14. Cryotherapy impairs knee joint position sense.

    PubMed

    Oliveira, R; Ribeiro, F; Oliveira, J

    2010-03-01

    The effects of cryotherapy on joint position sense are not clearly established; however it is paramount to understand its impact on peripheral feedback to ascertain the safety of using ice therapy before resuming exercise on sports or rehabilitation settings. Thus, the aim of the present study was to determine the effects of cryotherapy, when applied over the quadriceps and over the knee joint, on knee position sense. This within-subjects repeated-measures study encompassed fifteen subjects. Knee position sense was measured by open kinetic chain technique and active positioning at baseline and after cryotherapy application. Knee angles were determined by computer analysis of the videotape images. Twenty-minute ice bag application was applied randomly, in two sessions 48 h apart, over the quadriceps and the knee joint. The main effect for cryotherapy application was significant (F (1.14)=7.7, p=0.015) indicating an increase in both absolute and relative angular errors after the application. There was no significant main effect for the location of cryotherapy application, indicating no differences between the application over the quadriceps and the knee joint. In conclusion, cryotherapy impairs knee joint position sense in normal knees. This deleterious effect is similar when cryotherapy is applied over the quadriceps or the knee joint.

  15. Surgery for osteoarthritis of the knee.

    PubMed

    Richmond, John C

    2013-02-01

    Although total knee replacement is an excellent treatment of end-stage osteoarthritis of the knee in the older (>65 years) population, many patients with less severe disease are significantly impacted by their symptoms and have failed to respond to less invasive treatment alternatives. For this group, there are several less invasive surgical alternatives, including arthroscopic meniscectomy, grafting of symptomatic areas of bone marrow lesions, unloading osteotomy, and unicompartmental knee replacement. Current total knee arthroplasty designs can be expected to survive 20 years or more in the older, less active population. New materials may extend that survivorship.

  16. Immediate Effects of an Elastic Knee Sleeve on Frontal Plane Gait Biomechanics in Knee Osteoarthritis

    PubMed Central

    Schween, Raphael; Gehring, Dominic; Gollhofer, Albert

    2015-01-01

    Introduction Osteoarthritis of the knee affects millions of people. Elastic knee sleeves aim at relieving symptoms. While symptomatic improvements have been demonstrated as a consequence of elastic knee sleeves, evidence for biomechanical alterations only exists for the sagittal plane. We therefore asked what effect an elastic knee sleeve would have on frontal plane gait biomechanics. Methods 18 subjects (8 women, 10 men) with osteoarthritis of the medial tibiofemoral joint walked over ground with and without an elastic knee sleeve. Kinematics and forces were recorded and joint moments were calculated using an inverse dynamics approach. Conditions with sleeve and without sleeve were compared with paired t-Tests. Results With the sleeve, knee adduction angle at ground contact was reduced by 1.9±2.1° (P = 0.006). Peak knee adduction was reduced by 1.5±1.6° (P = 0.004). The first peak knee adduction moment and positive knee adduction impulse were decreased by 10.1% (0.74±0.9 Nm•kg-1; P = 0.002) and 12.9% (0.28±0.3 Nm•s•kg-1; P < 0.004), respectively. Conclusion Our study provides evidence that wearing an elastic knee sleeve during walking can reduce knee adduction angles, moments and impulse in subjects with knee osteoarthritis. As a higher knee adduction moment has previously been identified as a risk factor for disease progression in patients with medial knee osteoarthritis, we speculate that wearing a knee sleeve may be beneficial for this specific subgroup. PMID:25621488

  17. Unicondylar knee arthroplasty: a cementless perspective

    PubMed Central

    Forsythe, Michael E.; Englund, Roy E.; Leighton, Ross K.

    2000-01-01

    Objective To compare the results of cementless unicondylar knee arthroplasty (UKA) with those already reported in a similar study on cemented UKA. Design A case-series cross-sectional study. Setting The Queen Elizabeth II Health Sciences Centre, Dalhousie University, Halifax. Patients Fifty-one patients who underwent a total of 57 UKAs between May 1989 and May 1997. Inclusion criteria were osteoarthritis involving the predominantly the medial compartment of the knee, relative sparing of the other compartments, less than 15° of varus, minimal knee instability, and attendance at the postoperative clinical visit. Intervention Cementless UKA. Main outcome measures Clinical parameters that included pain, range of motion and the Knee Society Clinical Knee Score. Roentgenographic parameters that included α, β, γ and σ angles and the presence of periprosthetic radiolucency or loose beads. Results Age, weight, gender and follow-up interval did not significantly affect the clinical results in terms of pain, range of motion or knee score. Knees with more than 1 mm of radiolucency had significantly lower knee scores than those with no radiolucency. Knees that radiologically had loose beads also had significantly lower knee scores. The clinical outcomes of cementless UKA were comparable to those already reported on cemented UKA. Cementless femurs had less radiolucency than the cemented femurs, whereas cementless tibias had more radiolucency than their cemented counterparts. Conclusions Cementless UKA seems to be as efficacious as cemented UKA. However, there is some concern about the amount of radiolucency in the cementless tibial components. A randomized clinical trial comparing both cementless and cemented tibial components with a cementless femur (hybrid knee) is needed to further assess this controversial issue in UKA. PMID:11129829

  18. Astym® Therapy for the Management of Recalcitrant Knee Joint Stiffness after Total Knee Arthroplasty.

    PubMed

    Bhave, Anil; Corcoran, James; Cherian, Jeffery J; Mont, Michael A

    2016-01-01

    Knee stiffness is a common complication after total knee arthroplasty (TKA). Despite studies published on the surgical management of reduced range of motion (ROM) after TKA, there is limited evidence on the nonoperative management of joint and soft tissue imbalances possibly contributing to reduced knee ROM. This report assesses changes in ROM, pain, function, and patellar tendon length after Astym® joint mobilization use. A 38-year-old male professional skier had a right TKA 3 months before presentation with 2 subsequent manipulations under anesthesia secondary to persistent knee stiffness. He had patellar baja on radiograph, a reduced arc of ROM, reduced patellar mobility and muscular extensibility, and pain to palpation along the patellar tendon. He had 12 visits of physical therapy with the use of Astym®, patellar mobilization, and tibio-femoral mobilizations with movement. The patient also used a customized knee device at home for prolonged knee extension stretching. The patient was treated for 12 visits, along with home use of customized bracing for knee extension. Significant improvements were seen in pain, function, and ROM. He returned to work full-time, ambulated prolonged distances, and negotiated stairs pain-free. He also demonstrated resolution of patellar baja radiographically. Conservative management of recalcitrant knee joint stiffness after primary TKA can be effective in restoring knee mobility and reducing pain and activity limitation. A multimodal approach using Astym® treatment, customized knee bracing, and targeted joint mobilization can be effective in resolving knee joint stiffness.

  19. Total Knee Arthroplasty in Severe Unstable Knee: Case-Report and Literature Review

    PubMed Central

    Tahmasebi, Mohammad Naghi; Amjad, Gholamreza Ghorbani; Kaseb, Mohammad Hassan; Bashti, Kaveh

    2017-01-01

    Multiplanar or global laxity in arthritic knee is rare, most of this patients have neuromuscular disorder (post poliomyelitis, spinal dystrophy) or history of knee trauma. Ligament insufficiency and severe bone loss is significant in this patient. The estimated prevalence for the concurrence of charcot marie-tooth (CMT) with myasthenia gravis (MG) suggests an extremely rare event. We have presented a 54-year-old female patient with CMT and MG complaining of progressive pain, swelling, and crepitation of the knee joints who had been undergone total knee arthroplasty (TKA) with rotating hinge prosthesis. She had an acute myasthenia crisis soon after operation with prolonged intubation and intensive care unit admission. Radiographies and physical examination revealed bilateral severe unstable arthritic knee joints and left knee posterior dislocation. Short-term postoperative follow-up revealed improved knee function and resolution of all symptoms in the operated side. PMID:28271089

  20. Total Knee Arthroplasty for Severe Flexion Contracture in Rheumatoid Arthritis Knees

    PubMed Central

    Hwang, Youn Soo; Moon, Kyu Pill; Kim, Kyung Taek; Kim, Jin Wan; Park, Won Seok

    2016-01-01

    Flexion contracture deformities, as well as severe varus and valgus deformities of the knee joint, accompany osteoarthritis or rheumatoid arthritis (RA). In particular, severe flexion contracture deformity of the knee joint is often found in patients with RA, which renders them nonambulatory. This report describes a 26-year-old female patient diagnosed with RA 10 years ago. She had chronic joint pain, severe flexion contracture, valgus deformity in both knees, and limited range of motion in both knees and became nonambulatory. She underwent a total knee arthroplasty (TKA) and serial casting and physical therapy to restore stable joint movement and correct knee joint deformity. Her pain was successfully relieved, and she was able to walk after surgery. Here, we report the excellent results of TKA in this RA patient with severe flexion contracture of both knees. PMID:27894181

  1. Effect of patellar thickness on knee flexion in total knee arthroplasty: a biomechanical and experimental study.

    PubMed

    Abolghasemian, Mansour; Samiezadeh, Saeid; Sternheim, Amir; Bougherara, Habiba; Barnes, C Lowry; Backstein, David J

    2014-01-01

    A biomechanical computer-based model was developed to simulate the influence of patellar thickness on passive knee flexion after arthroplasty. Using the computer model of a single-radius, PCL-sacrificing knee prosthesis, a range of patella-implant composite thicknesses was simulated. The biomechanical model was then replicated using two cadaveric knees. A patellar-thickness range of 15 mm was applied to each of the knees. Knee flexion was found to decrease exponentially with increased patellar thickness in both the biomechanical and experimental studies. Importantly, this flexion loss followed an exponential pattern with higher patellar thicknesses in both studies. In order to avoid adverse biomechanical and functional consequences, it is recommended to restore patellar thickness to that of the native knee during total knee arthroplasty.

  2. In vivo knee kinematics in patients with bilateral total knee arthroplasty of 2 designs.

    PubMed

    Okamoto, Nobukazu; Breslauer, Leigh; Hedley, Anthony K; Mizuta, Hiroshi; Banks, Scott A

    2011-09-01

    Many younger and highly active patients desire to achieve high flexion after total knee arthroplasty. This study's purpose was to determine if a contemporary total knee arthroplasty design improved functional knee flexion compared with a traditional total knee arthroplasty in patients living a Western lifestyle. Ten patients with bilateral total knee arthroplasty of 2 types were studied during weight-bearing lunge, kneeling, and stair activities using fluoroscopic imaging. There were no differences in maximum knee flexion during lunging or kneeling. Statistically significant differences in tibial rotation and condylar translation were observed during the 3 activities. Although several joint kinematic differences were observed, no important functional differences were observed in clinically excellent, high performing subjects with bilateral total knee arthroplasty of 2 types.

  3. The effect of orthotic devices on knee adduction moment, pain and function in medial compartment knee osteoarthritis: a literature review.

    PubMed

    Baghaei Roodsari, Roshanak; Esteki, Ali; Aminian, Gholamreza; Ebrahimi, Ismaeil; Mousavi, Mohammad Ebramim; Majdoleslami, Basir; Bahramian, Fatemeh

    2016-03-15

    Background Knee braces and foot orthoses are commonly used to improve knee adduction moment, pain and function in subjects with knee osteoarthritis (OA). However, no literature review has been performed to compare the effects of foot orthoses and knee braces in this group of patients. Purpose The aim of this review was to evaluate the effects of foot orthoses and knee braces on knee adduction moment, pain and function in individuals with knee OA. Study design Literature review. Method The search strategy was based on the Population Intervention Comparison Outcome method. A search was performed in PubMed, Science Direct, Google Scholar and ISI web of knowledge databases using the PRISMA method and based on selected keywords. Thirty-one related articles were selected for final evaluation. Results The results of the analysis of these studies demonstrated that orthotic devices reduce knee adduction moment and also improve pain and function in individuals with knee OA. Conclusion Foot orthoses may be more effective in improving pain and function in subjects with knee OA. Both knee braces and foot orthoses reduce the knee adduction moment in knee OA and consequently patients typically do not need to use knee braces for a long period of time. Also, foot orthoses and knee braces may be more effective for medial compartment knee OA patients due to the fact that this treatment helps improve pain and function. Implications for Rehabilitation Knee braces and foot orthoses are commonly used for improving knee adduction moment, pain and function in subjects with knee osteoarthritis (OA). Orthotic devices can reduce knee adduction moment, pain and improve function in knee OA. The combined use of a knee braces and foot orthoses can provide more improvement in knee adduction moment, reduced pain and increased function.

  4. Arthroscopic knee debridement can delay total knee replacement in painful moderate haemophilic arthropathy of the knee in adult patients.

    PubMed

    Rodriguez-Merchan, E Carlos; Gomez-Cardero, Primitivo

    2016-09-01

    The role of arthroscopic debridement of the knee in haemophilia is controversial in the literature. The purpose of this study is to describe the results of arthroscopic knee debridement (AKD), with the aim of determining whether it is possible to delay total knee replacement (TKR) for painful moderate haemophilic arthropathy of the knee in adult patients. In a 14-year period (1998-2011), AKD was performed for moderate haemophilic arthropathy of the knee in 27 patients with haemophilia A. Their average age at operation was 28.6 years (range 26-39 years). Indications for surgery were as follows: more than 90° of knee flexion, flexion deformity less than 30°, good axial alignment of the knee, good patellar alignment, and pain above >60 points in a visual analogue scale [0 (no pain) to 100 points]. Secondary haematological prophylaxis and rehabilitation (physiotherapy) was given for at least 3 months after surgery. Follow-up was for an average of 7.5 years (range 2-14 years). We assessed the clinical outcome before surgery and at the time of latest follow-up using the Knee Society pain and function scores, the range of motion, and the radiological score of the World Federation of Haemophilia. Knee Society pain scores improved from 39 preoperatively to 66 postoperatively, and function scores improved from 36 to 52. Range of motion improved on an average from -15° of extension and 90° of flexion before surgery, to -5° of extension and 110° of flexion at the last follow-up. A radiological deterioration of 2.8 points on average was found. There were two (7.4%) postoperative complications (haemarthroses resolved by joint aspiration). One patient (3.7%) required a TKR 12.5 years later. AKD should be considered in painful moderate haemophilic arthropathy of the knee in adult patients to delay TKR.

  5. KNEE-JOINT LOADING IN KNEE OSTEOARTHRITIS: INFLUENCE OF ABDOMINAL AND THIGH FAT

    PubMed Central

    Messier, Stephen P.; Beavers, Daniel P.; Loeser, Richard F.; Carr, J. Jeffery; Khajanchi, Shubham; Legault, Claudine; Nicklas, Barbara J.; Hunter, David J.; DeVita, Paul

    2014-01-01

    Purpose Using three separate models that included total body mass, total lean and total fat mass, and abdominal and thigh fat as independent measures, we determined their association with knee-joint loads in older overweight and obese adults with knee osteoarthritis (OA). Methods Fat depots were quantified using computed tomography and total lean and fat mass determined with dual energy x-ray absorptiometry in 176 adults (age = 66.3 yr., BMI = 33.5 kg·m−2) with radiographic knee OA. Knee moments and joint bone-on-bone forces were calculated using gait analysis and musculoskeletal modeling. Results Higher total body mass was significantly associated (p ≤ 0.0001) with greater knee compressive and shear forces, compressive and shear impulses (p < 0.0001), patellofemoral forces (p< 0.006), and knee extensor moments (p = 0.003). Regression analysis with total lean and total fat mass as independent variables revealed significant positive associations of total fat mass with knee compressive (p = 0.0001), shear (p < 0.001), and patellofemoral forces (p = 0.01) and knee extension moment (p = 0.008). Gastrocnemius and quadriceps forces were positively associated with total fat mass. Total lean mass was associated with knee compressive force (p = 0.002). A regression model that included total thigh and total abdominal fat found both were significantly associated with knee compressive and shear forces (p ≤ 0.04). Thigh fat was associated with the knee abduction (p = 0.03) and knee extension moment (p = 0.02). Conclusions Thigh fat, consisting predominately of subcutaneous fat, had similar significant associations with knee joint forces as abdominal fat despite its much smaller volume and could be an important therapeutic target for people with knee OA. PMID:25133996

  6. Prophylactic Knee Braces: Where Do They Stand?

    ERIC Educational Resources Information Center

    McCarthy, Paul

    1988-01-01

    The effectiveness of knee braces in preventing knee injuries in football is inconclusive. This article reviews research from epidemiologic, cadaver, and surrogate studies; discusses reasons for conflicting study results, including research design problems; and describes alternative approaches that have been suggested. (IAH)

  7. [Ossifying bursitis praepatellaris of the knee joint].

    PubMed

    Erler, M

    2009-01-01

    A 53-year-old patient was admitted to our hospital with a tumour at the site of the left knee joint praepatellar. The diagnostic imaging, operative findings and histology showed a chronic ossifying bursitis praepatellaris of the knee joint. Aetiology and pathogenesis of the ossifying bursitis are discussed.

  8. Jumper's Knee (Patellar Tendonitis) (For Parents)

    MedlinePlus

    ... regularly play sports that involve a lot of repetitive jumping — like track and field (particularly high-jumping), basketball, volleyball, gymnastics, running, and soccer — can put a lot of strain on their knees. Jumper's knee can seem like a minor injury that isn't really that serious. Because of ...

  9. Knee Braces to Prevent Injuries in Football.

    ERIC Educational Resources Information Center

    Physician and Sportsmedicine, 1986

    1986-01-01

    Five physicians discuss the use of knee braces to prevent injuries in football players. Questions are raised regarding the strength and design of the braces, whether they prestress the knee in some cases, and whether they actually reduce injuries. More clinical and biomechanical research is called for. (MT)

  10. The acute swollen knee: diagnosis and management.

    PubMed

    Gupte, Chinmay; St Mart, Jean-Pierre

    2013-07-01

    The acutely swollen knee is a common presentation of knee pathology in both primary care and the emergency department. The key to diagnosis and management is a thorough history and examination to determine the primary pathology, which includes inflammation, infection or a structural abnormality in the knee. The location of pain and tenderness can aid to localization of structural pathology even before radiological tests are requested, and indeed inform the investigations that should be carried out. Aspiration of an acutely swollen knee can aid diagnosis and help relieve pain. The management of the swollen knee depends on underlying pathology and can range from anti-inflammatory medication for inflammation to operative intervention for a structural abnormality.

  11. The acute swollen knee: diagnosis and management

    PubMed Central

    Gupte, Chinmay; St Mart, Jean-Pierre

    2013-01-01

    The acutely swollen knee is a common presentation of knee pathology in both primary care and the emergency department. The key to diagnosis and management is a thorough history and examination to determine the primary pathology, which includes inflammation, infection or a structural abnormality in the knee. The location of pain and tenderness can aid to localization of structural pathology even before radiological tests are requested, and indeed inform the investigations that should be carried out. Aspiration of an acutely swollen knee can aid diagnosis and help relieve pain. The management of the swollen knee depends on underlying pathology and can range from anti-inflammatory medication for inflammation to operative intervention for a structural abnormality. PMID:23821708

  12. Gait Analysis of Conventional Total Knee Arthroplasty and Bicruciate Stabilized Total Knee Arthroplasty Using a Triaxial Accelerometer

    PubMed Central

    Saito, Hidetomo; Aizawa, Toshiaki; Miyakoshi, Naohisa; Shimada, Yoichi

    2016-01-01

    One component of conventional total knee arthroplasty is removal of the anterior cruciate ligament, and the knee after total knee arthroplasty has been said to be a knee with anterior cruciate ligament dysfunction. Bicruciate stabilized total knee arthroplasty is believed to reproduce anterior cruciate ligament function in the implant and provide anterior stability. Conventional total knee arthroplasty was performed on the right knee and bicruciate stabilized total knee arthroplasty was performed on the left knee in the same patient, and a triaxial accelerometer was fitted to both knees after surgery. Gait analysis was then performed and is reported here. The subject was a 78-year-old woman who underwent conventional total knee arthroplasty on her right knee and bicruciate stabilized total knee arthroplasty on her left knee. On the femoral side with bicruciate stabilized total knee arthroplasty, compared to conventional total knee arthroplasty, there was little acceleration in the x-axis direction (anteroposterior direction) in the early swing phase. Bicruciate stabilized total knee arthroplasty may be able to replace anterior cruciate ligament function due to the structure of the implant and proper anteroposterior positioning. PMID:27648328

  13. [Jumper's knee--a review].

    PubMed

    Tibesku, C O; Pässler, H H

    2005-06-01

    Jumper's knee has been defined as painful chronic overuse injury of the extensor mechanism of the knee joint. The disease has a high incidence in jumping sports and depends on training frequency and level of performance. Its natural course is protracted, repetitive, and often bilaterally occurring. Its etiology is a chronic overload of the knee extensor mechanism which is triggered by jumping sports (volleyball, basketball etc.) as well as different intrinsic (ligamentous laxity, Q-angle, patella height, tenderness, pattern of force development) and extrinsic dispositions (frequency of training, level of performance, hardness of underground). The place of pathology most often is the osteo-tendinous transition zone of the proximal patellar tendon. Histologic evaluation of the tendon showed that the disease is rather degenerative than inflammatory. The diagnosis is primarily based on the typical sports history, physical examination, and ultrasound. MRI is helpful in operation planning. Plain radiography, CT, and bone scans are used to rule out differential diagnoses. Therapy should be chosen according to the stage of the disease and usually starts with a non-surgical approach. This includes rest from sports activities, immobilisation, non-steroid antiphlogistics, para-tendinous cortisone injections, massage, electric therapy, ultrasound and extracorporal shock waves. Afterwards an increase of activities is begun (moderate training, adequate warm-up, ice cooling after activity, muscle stretching, eccentric strengthening of the quadriceps). Patella straps and soft insoles are used as prevention. Up to 42 % of patients need surgical therapy after failure of long-lasting non-surgical measures, carried out either open or arthroscopically. Surgical principles include excision of the para-tendon, excision of the degenerative tissue, resection of the lower patella pole, and longitudinal incisions into the tendon. Most patients are pain-free after surgery but return to sports

  14. Radionuclide therapy for arthritic knees

    SciTech Connect

    Doepel, L.K.

    1985-02-08

    A new radionuclide therapeutic approach for rheumatoid arthritis of the knee is described. This therapy combines a short-lived radionuclide with a carrier whose physical and chemical characteristics aid retention of the radioactive particles within the joint. Joining a radionuclide to a particulate carrier had not been explored previously as a potential method for inhibiting radiation leakage. The treatment couples the rare earth element dysprosium 165 to ferric hydroxide in macroaggregate form (size range: 3 to 10 ..mu..m). After the relatively inert iron complex penetrates the synovium, it causes cell death. Macrophages and phagocytes clear away the cellular debris, essentially eliminating the synovium.

  15. Automatic locking knee brace joint

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce (Inventor)

    1995-01-01

    This invention is an apparatus for controlling the pivotal movement of a knee brace comprising a tang-and-clevis joint that has been uniquely modified. Both the tang and the clevis have a set of teeth that, when engaged, can lock the tang and the clevis together. In addition, the tang is biased away from the clevis. Consequently, when there is no axial force (i.e., body weight) on the tang, the tang is free to pivot within the clevis. However, when an axial force is exerted on the tang, the tang is pushed into the clevis, both sets of teeth engage, and the tang and the clevis lock together.

  16. Molecular Biomarkers of Knee Pathology.

    PubMed

    Cuellar, Vanessa; Strauss, Eric

    2017-01-01

    The identification of biomarkers has become increasingly important in our fundamental understanding of the molecular basis for disease and subsequently in the advancement of modern medicine. Biomarkers have been identified in a plethora of normal and pathologic conditions and are most often found in blood, tissue, or synovial fluid. Orthopaedic research has more recently focused on biomarkers of cartilage and joint diseases, with an emphasis on understanding the molecular underpinnings of their pathophysiology. This article focuses on the biomarkers identified to date in several select knee pathologies and how further research can contribute to new diagnostic tools and targeted therapeutics.

  17. MRI EVALUATION OF KNEE CARTILAGE

    PubMed Central

    Rodrigues, Marcelo Bordalo; Camanho, Gilberto Luís

    2015-01-01

    Through the ability of magnetic resonance imaging (MRI) to characterize soft tissue noninvasively, it has become an excellent method for evaluating cartilage. The development of new and faster methods allowed increased resolution and contrast in evaluating chondral structure, with greater diagnostic accuracy. In addition, physiological techniques for cartilage assessment that can detect early changes before the appearance of cracks and erosion have been developed. In this updating article, the various techniques for chondral assessment using knee MRI will be discussed and demonstrated. PMID:27022562

  18. Knee injuries account for the sports-related increased risk of knee osteoarthritis.

    PubMed

    Thelin, N; Holmberg, S; Thelin, A

    2006-10-01

    Increased risk of osteoarthritis has been found among athletes active in different kinds of sports. Knee injury is an established risk factor for knee osteoarthritis. In this population-based case-control study we investigated the risk of knee osteoarthritis with respect to sports activity and previous knee injuries. A total of 825 cases with x-ray-verified femorotibial osteoarthritis were identified at six hospitals in southern Sweden. The cases were matched (age, sex and residential area) with 825 controls from the general population. Mailed questionnaire data on sports activity for more than 1 year after the age of 16, knee injuries and confounding variables (weight, height, heredity, smoking and occupation) were collected and analyzed using logistic regression models. The response frequency was 89%. Among men knee osteoarthritis was related to soccer (odds ratio (OR) 1.6, 95% confidence interval (CI) 1.1-2.2), ice hockey (OR 1.9, 95% CI 1.2-3.0) and tennis (OR 2.0, 95% CI 1.1-3.8) but not to track and field sports, cross-country skiing, and orienteering. After adjustment for confounding variables soccer and ice hockey remained significantly related to knee osteoarthritis, but after adjustment for knee injuries no significant relation remained. The sports-related increased risk for knee osteoarthritis was explained by knee injuries.

  19. Real-Time Tracking of Knee Adduction Moment in Patients with Knee Osteoarthritis

    PubMed Central

    Kang, Sang Hoon; Lee, Song Joo; Zhang, Li-Qun

    2014-01-01

    Background The external knee adduction moment (EKAM) is closely associated with the presence, progression, and severity of knee osteoarthritis (OA). However, there is a lack of convenient and practical method to estimate and track in real-time the EKAM of patients with knee OA for clinical evaluation and gait training, especially outside of gait laboratories. New Method A real-time EKAM estimation method was developed and applied to track and investigate the EKAM and other knee moments during stepping on an elliptical trainer in both healthy subjects and a patient with knee OA. Results Substantial changes were observed in the EKAM and other knee moments during stepping in the patient with knee OA. Comparison with Existing Method(s) This is the first study to develop and test feasibility of real-time tracking method of the EKAM on patients with knee OA using 3-D inverse dynamics. Conclusions The study provides us an accurate and practical method to evaluate in real-time the critical EKAM associated with knee OA, which is expected to help us to diagnose and evaluate patients with knee OA and provide the patients with real-time EKAM feedback rehabilitation training. PMID:24361759

  20. Anterior knee pain and cold knees: a possible association in women.

    PubMed

    Selfe, James; Sutton, Chris; Hardaker, Natalie J; Greenhalgh, Sue; Karki, Anne; Dey, Paola

    2010-10-01

    Abnormal reactions to environmental cold have been observed in some patients with Anterior Knee Pain (AKP). The aims of this study were to investigate whether palpation of the knee could classify patients into those with and those without cold knees; whether this classification could be objectively validated using thermal imaging; whether the cold and not cold knee groups varied in response to a cold stress test and in patient-reported measures. Fifty eight patients were recruited; palpation classified them into cold and not cold groups. Twenty-one (36%) patients were classified as having a cold knee by palpation: fourteen (36%) females and seven males (37%). Preliminary analysis suggested gender might be an effect modifier and the number of men was small, therefore the analysis focussed on females. Women with cold knees had a significantly smaller patellar skin fold, lower levels of activity and worse scores on the MFIQ, there also appeared to be an association with a traumatic onset. Women with cold knees were more likely to report cold weather affected their knees and they preferred a hot water bottle compared to an ice-pack on their knee; there was also a trend towards having to wear extra tights/long johns in the winter. This study has helped to define a clinical profile for a group of females with AKP and cold knees. This group appears to demonstrate a mild form of Reflex Sympathetic Dystrophy.

  1. Six degree-of-freedom knee joint kinematics in obese individuals with knee pain during gait

    PubMed Central

    Li, Jing-Sheng; Tsai, Tsung-Yuan; Felson, David T.; Li, Guoan; Lewis, Cara L.

    2017-01-01

    Knee joint pain is a common symptom in obese individuals and walking is often prescribed as part of management programs. Past studies in obese individuals have focused on standing alignment and kinematics in the sagittal and coronal planes. Investigation of 6 degree-of-freedom (6DOF) knee joint kinematics during standing and gait is important to thoroughly understand knee function in obese individuals with knee pain. This study aimed to investigate the 6DOF knee joint kinematics in standing and during gait in obese patients using a validated fluoroscopic imaging system. Ten individuals with obesity and knee pain were recruited. While standing, the knee was in 7.4±6.3°of hyperextension, 2.8±3.3° of abduction and 5.6±7.3° of external rotation. The femoral center was located 0.7±3.1mm anterior and 5.1±1.5mm medial to the tibial center. During treadmill gait, the sagittal plane motion, i.e., flexion/extension and anterior-posterior translation, showed a clear pattern. Specifically, obese individuals with knee pain maintained the knee in more flexion and more anterior tibial translation during most of the stance phase of the gait cycle and had a reduced total range of knee flexion when compared to a healthy non-obese group. In conclusion, obese individuals with knee pain used hyperextension knee posture while standing, but maintained the knee in more flexion during gait with reduced overall range of motion in the 6DOF analysis. PMID:28339477

  2. Three-dimensional dynamic analysis of knee joint during gait in medial knee osteoarthritis using loading axis of knee.

    PubMed

    Nishino, Katsutoshi; Omori, Go; Koga, Yoshio; Kobayashi, Koichi; Sakamoto, Makoto; Tanabe, Yuji; Tanaka, Masaei; Arakawa, Masaaki

    2015-07-01

    We recently developed a new method for three-dimensional evaluation of mechanical factors affecting knee joint in order to help identify factors that contribute to the progression of knee osteoarthritis (KOA). This study aimed to verify the clinical validity of our method by evaluating knee joint dynamics during gait. Subjects were 41 individuals (14 normal knees; 8 mild KOAs; 19 severe KOAs). The positions of skin markers attached to the body were captured during gait, and bi-planar X-ray images of the lower extremities were obtained in standing position. The positional relationship between the markers and femorotibial bones was determined from the X-ray images. Combining this relationship with gait capture allowed for the estimation of relative movement between femorotibial bones. We also calculated the point of intersection of loading axis of knee on the tibial proximal surface (LAK point) to analyze knee joint dynamics. Knee flexion range in subjects with severe KOA during gait was significantly smaller than that in those with normal knees (p=0.011), and knee adduction in those with severe KOA was significantly larger than in those with mild KOA (p<0.000). LAK point was locally loaded on the medial compartment of the tibial surface as KOA progressed, with LAK point of subjects with severe KOA rapidly shifting medially during loading response. Local loading and medial shear force were applied to the tibial surface during stance phase as medial KOA progressed. Our findings suggest that our method is useful for the quantitative evaluation of mechanical factors that affect KOA progression.

  3. Can a finite set of knee extension in supine position be used for a knee functional examination?

    PubMed

    Marin, F; Sangeux, M; Charleux, F; Ho Ba Tho, M-C; Dürselen, L

    2006-01-01

    The kinematic magnetic resonance imaging technique has been developed to provide a functional examination of the knee. Technical limitations require this examination to be performed in supine position, and the knee motion is represented by an assembly of static positions at different knee angles. However, the main knee function is to support the body weight and perform continuous motion, e.g. parallel squat. Our study quantified the knee kinematics of 20 healthy subjects in different motion conditions (finite and continuous) and in different mechanical conditions (continuous unloaded and continuous loaded). We evaluated the angular and localisation difference of a finite helical axis of the knee motion for parallel squat, continuous knee extension in supine position and the finite set of knee extension in supine position. We found large inter-individual dispersion. The majority of subjects had equivalent knee kinematics between continuous knee extension and the finite set of knee extension in supine position, but not between continuous knee extension in supine position and the parallel squat. Therefore, results from a functional examination of a finite set of knee extensions in supine position do not represent the knee motion in a parallel squat. Our results suggest that functional examination of the knee from magnetic resonance imaging do not necessarily reflect the physiological kinematics of the knee. Further investigation should focus on a new magnetic resonance imaging acquisition protocol that allows image acquisition during weight bearing or includes a special device which reproduces the loaded condition.

  4. Intraoperative knee anthropometrics: correlation with cartilage wear.

    PubMed

    Rooney, N; Fitzpatrick, D P; Beverland, D E

    2006-08-01

    Accurate knee morphology is of value in determining the correct sizing of prosthetic implants. Intraoperative measurement of key linear dimensional variables was carried out on 196 Caucasian knees (osteoarthritic patients: 68 male and 128 female). Of the 196 knees measured, 70 had extensive cartilage degeneration. Statistical analysis was carried out on this large sample size of data. Summary statistics and correlation coefficients between variables were determined and compared between subgroups. Male knees were on average larger than female knees. Higher correlation was found between variables for males than between variables for females. Overall, the patellar dimensions were seen to correlate least well with other anatomical variables. High correlation between femoral variables supports current femoral sizing procedure, although routine patellar resection practices are called into question. Average values for the 70 knees with extensive cartilage degeneration were significantly smaller (P < 0.01) than their counterparts for the other 126 knees. For a measurement not containing cartilage, such as femoral epicondylar width, this difference cannot be accounted for by the loss of cartilage owing to wear. This suggests that, for similar height and weight, a naturally narrower femoral epicondylar width may be associated with severe osteoarthritis.

  5. Translational and rotational knee joint stability in anterior and posterior cruciate-retaining knee arthroplasty.

    PubMed

    Lo, JiaHsuan; Müller, Otto; Dilger, Torsten; Wülker, Nikolaus; Wünschel, Markus

    2011-12-01

    This study investigated passive translational and rotational stability properties of the intact knee joint, after bicruciate-retaining bi-compartmental knee arthroplasty (BKA) and after posterior cruciate retaining total knee arthroplasty (TKA). Fourteen human cadaveric knee specimens were used in this study, and a robotic manipulator with six-axis force/torque sensor was used to test the joint laxity in anterior-posterior translation, valgus-varus, and internal-external rotation. The results show the knee joint stability after bicruciate-retaining BKA is similar to that of the native knee. On the other hand, the PCL-retaining TKA results in inferior joint stability in valgus, varus, external rotation, anterior and, surprisingly, posterior directions. Our findings suggest that, provided functional ligamentous structures, bicruciate-retaining BKA is a biomechanically attractive treatment for joint degenerative disease.

  6. Human knee joint anatomy revisited: morphometry in the light of sex-specific total knee arthroplasty.

    PubMed

    Dargel, Jens; Michael, Joern W P; Feiser, Janna; Ivo, Roland; Koebke, Juergen

    2011-04-01

    This study investigates differences in the anatomy of male and female knee joints to contribute to the current debate on sex-specific total knee implants. Morphometric data were obtained from 60 human cadaver knees, and sex differences were calculated. All data were corrected for height, and male and female specimens presenting with an identical length of the femur were analyzed as matched pairs. Male linear knee joint dimensions were significantly larger when compared with females. When corrected for differences in height, medial-lateral dimensions of male knees were significantly larger than female; however, matched paired analysis did not prove these differences to be consistent. Although implant design should focus interindividual variations in knee joint anatomy, our data do not support the concept of a female-specific implant design.

  7. Knee range of motion after total knee arthroplasty: how important is this as an outcome measure?

    PubMed

    Miner, Andrew L; Lingard, Elizabeth A; Wright, Elizabeth A; Sledge, Clement B; Katz, Jeffrey N

    2003-04-01

    We investigated the relationship of knee range of motion (ROM) and function in a prospective, observational study of primary total knee arthroplasty (TKA). Preoperative and 12-month data were collected on 684 patients, including knee ROM, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function questionnaire scores, patient satisfaction, and perceived improvement in quality of life (QOL). Only modest correlations were found between knee ROM and WOMAC function (r<0.34). At 12 months we found significantly worse WOMAC function scores for patients with <95 degrees flexion compared with patients with > or =95 degrees (mean, 61.9 vs 75.0; P<.0001). In linear regression models, WOMAC pain and function scores at 12 months were both correlates of patient satisfaction and perceived improvement in QOL (standardized beta>3.5; P<.0001), but knee flexion was not. For assessment of these outcomes, WOMAC function appears to be more important than knee flexion.

  8. Osteotomies about the knee: AAOS exhibit selection.

    PubMed

    Uquillas, Carlos; Rossy, William; Nathasingh, Christopher K; Strauss, Eric; Jazrawi, Laith; Gonzalez-Lomas, Guillem

    2014-12-17

    Varus or valgus malalignment of the lower extremity can alter the load distribution across the knee and hasten the development of focal osteoarthritis. Although knee arthroplasty remains an effective option for end-stage arthritis, it is not typically recommended in the young, active patient. In the setting of painful unicompartmental cartilage injury in a mechanically malaligned limb, alignment correction by osteotomy has been shown to slow the progression of osteoarthritis and lessen pain. In this review, we will discuss the different options, indications, and techniques for osteotomies about the knee.

  9. SYNOVIAL GIANT CELL TUMOR OF THE KNEE.

    PubMed

    Abdalla, Rene Jorge; Cohen, Moisés; Nóbrega, Jezimar; Forgas, Andrea

    2009-01-01

    Synovial giant cell tumor is a benign neoplasm, rarely reported in the form of malignant metastasis. Synovial giant cell tumor most frequently occurs on the hand, and, most uncommon, on the ankle and knee. In the present study, the authors describe a rare case of synovial giant cell tumor on the knee as well as the treatment approach. Arthroscopy has been shown, in this case, to be the optimal method for treating this kind of lesion, once it allowed a less aggressive approach, while providing good visualization of all compartments of knee joint and full tumor resection.

  10. Which osteotomy for a valgus knee?

    PubMed Central

    Cipolla, Massimo; Cerullo, Guglielmo; Franco, Vittorio; Giannì, Enrico

    2009-01-01

    A valgus knee is a disabling condition that can affect patients of all ages. Antivalgus osteotomy of the knee is the treatment of choice to correct the valgus, to eliminate pain in the young or middle age patient, and to avoid or delay a total knee replacement. A distal femoral lateral opening wedge procedure appears to be one of the choices for medium or large corrections and is particularly easy and precise if compared to the medial femoral closing wedge osteotomy. However, if the deformity is minimal, a tibial medial closing wedge osteotomy can be done with a faster healing and a short recovery time. PMID:19547972

  11. Gap balancing in total knee arthroplasty.

    PubMed

    Bottros, John; Gad, Bishoy; Krebs, Viktor; Barsoum, Wael K

    2006-06-01

    It is well known that the success of total knee arthroplasty is collectively dependent on the proper recreation of the joint line, appropriate soft tissue balancing, and respectful management of the extensor mechanism. One of the most decisive factors within the surgeon's control is the reestablishment of proper knee kinematics through both medial-lateral and flexion-extension ligamentous balancing. This can be accomplished only by a comprehensive intraoperative evaluation in full flexion, mid flexion, and full extension to minimize potential gap mismatches. Most of the discussion will focus on this aspect of soft tissue balancing, but this does not undermine the importance of the other aforementioned principles of successful knee arthroplasty.

  12. Proprioception and Knee Arthroplasty: A Literature Review.

    PubMed

    Wodowski, Andrew J; Swigler, Colin W; Liu, Hongchao; Nord, Keith M; Toy, Patrick C; Mihalko, William M

    2016-04-01

    Proprioceptive mechanoreceptors provide neural feedback for position in space and are critical for three-dimensional interaction. Proprioception is decreased with osteoarthritis of the knees, which leads to increased risk of falling. As the prevalence of osteoarthritis increases so does the need for total knee arthroplasty (TKA), and knowing the effect of TKA on proprioception is essential. This article reviews the literature regarding proprioception and its relationship to balance, aging, osteoarthritis, and the effect of TKA on proprioception. Knee arthroplasty involving retention of the cruciate ligaments is also reviewed, as well the evidence of proprioception in the posterior cruciate ligament after TKA.

  13. SYNOVIAL GIANT CELL TUMOR OF THE KNEE

    PubMed Central

    Abdalla, Rene Jorge; Cohen, Moisés; Nóbrega, Jezimar; Forgas, Andrea

    2015-01-01

    Synovial giant cell tumor is a benign neoplasm, rarely reported in the form of malignant metastasis. Synovial giant cell tumor most frequently occurs on the hand, and, most uncommon, on the ankle and knee. In the present study, the authors describe a rare case of synovial giant cell tumor on the knee as well as the treatment approach. Arthroscopy has been shown, in this case, to be the optimal method for treating this kind of lesion, once it allowed a less aggressive approach, while providing good visualization of all compartments of knee joint and full tumor resection. PMID:27004193

  14. Unicompartmental Knee Osteoarthritis (UKOA): Unicompartmental Knee Arthroplasty (UKA) or High Tibial Osteotomy (HTO)?

    PubMed Central

    Rodriguez-Merchan, E. Carlos

    2016-01-01

    The aim of this review article is to analyze the results of high tibial osteotomy compared to unicompartmental knee arthroplasty in patients with unicompartmental knee osteoarthritis. The search engine used was PubMed. The keywords were: “high tibial osteotomy versus unicompartmental knee arthroplasty”. Twenty-one articles were found on 28 February 2015, but only eighteen were selected and reviewed because they strictly focused on the topic. In a meta-analysis the ratio for an excellent outcome was higher in unicompartmental knee arthroplasty than high tibial osteotomy and the risks of revision and complications were lower in the former. A prospective comparative study showed that unicompartmental knee arthroplasty offers better long-term success (77% for unicompartmental knee arthroplasty and 60% for high tibial osteotomy at 7-10 years). However, a review of the literature showed no evidence of superior results of one treatment over the other. A multicenter study stated that unicompartmental knee osteoarthritis without constitutional deformity should be treated with unicompartmental knee arthroplasty while in cases with constitutional deformity high tibial osteotomy should be indicated. A case control study stated that unicompartmental knee arthroplasty offers a viable alternative to high tibial osteotomy if proper patient selection is done. The literature is still controversial regarding the best surgical treatment for unicompartmental knee osteoarthritis (high tibial osteotomy or unicompartmental knee arthroplasty). However, unicompartmental knee arthroplasty utilization is increasing, while high tibial osteotomy utilization is decreasing, and a meta-analysis has shown better outcomes and less risk of revision and complications in the former. A systematic review has found that with correct patient selection, both procedures show effective and reliable results. However, prospective randomized studies are needed in order to answer the question of this article

  15. Biceps tendinitis as a cause of acute painful knee after total knee arthroplasty.

    PubMed

    Pandher, Dilbans Singh; Boparai, Randhir Singh; Kapila, Rajesh

    2009-12-01

    The case report highlights an unusual case of posterolateral knee pain after total knee arthroplasty. Tendinitis of the patellar tendon or pes anserinus is a common complication after total knee arthroplasty; however, there is no report in the literature regarding the biceps femoris tendinitis causing acute pain in the early postoperative period. In this case, the biceps tendinitis was diagnosed and treated by ultrasound-guided injection into the tendon sheath.

  16. Is Lifelong Knee Joint Force from Work, Home, and Sport Related to Knee Osteoarthritis?

    PubMed Central

    Ratzlaff, Charles R.; Koehoorn, Mieke; Cibere, Jolanda; Kopec, Jacek A.

    2012-01-01

    Purpose. To investigate the association of cumulative lifetime knee joint force on the risk of self-reported medically-diagnosed knee osteoarthritis (OA). Methods. Exposure data on lifetime physical activity type (occupational, household, sport/recreation) and dose (frequency, intensity, duration) were collected from 4,269 Canadian men and women as part of the Physical Activity and Joint Heath cohort study. Subjects were ranked in terms of the “cumulative peak force index”, a measure of lifetime mechanical knee force. Multivariable logistic regression was conducted to obtain adjusted effects for mean lifetime knee force on the risk of knee OA. Results. High levels of total lifetime, occupational and household-related force were associated with an increased in risk of OA, with odds ratio's ranging from approximately 1.3 to 2. Joint injury, high BMI and older age were related to risk of knee OA, consistent with previous studies. Conclusions. A newly developed measure of lifetime mechanical knee force from physical activity was employed to estimate the risk of self-reported, medically-diagnosed knee OA. While there are limitations, this paper suggests that high levels of total lifetime force (all domains combined), and occupational force in men and household force in women were risk factors for knee OA. PMID:22848225

  17. A comparative evaluation of the Adaptive knee and Catech knee joints: a preliminary study.

    PubMed

    Jepson, F; Datta, D; Harris, I; Heller, B; Howitt, J; McLean, J

    2008-03-01

    The Adaptive knee joint is a microprocessor-controlled prosthetic knee that incorporates both pneumatic and hydraulic control in one electronic unit. Pneumatic control is said to provide control during swing phase and the hydraulic control during the stance phase of the gait. This hybrid controller is triggered by a computer contained within the knee that responds to input from force, time and angle sensors. The microprocessor then selects an appropriate speed and stability setting. The Catech knee joint is a conventional hydraulic knee joint. The aim of this study was to compare the Adaptive and Catech knee joints in established trans-femoral amputees. The patients meeting the inclusion criteria were all established trans-femoral amputees using the Catech knee joint. The study was carried out by performing gait analysis, assessing energy requirements using the Physiological Cost Index (PCI) and using questionnaires. There was no significant benefit gained from the use of the Adaptive knee over the Catech knee joint in our small study group.

  18. EFFECTS OF THE GENIUM MICROPROCESSOR KNEE SYSTEM ON KNEE MOMENT SYMMETRY DURING HILL WALKING

    PubMed Central

    Highsmith, M. Jason; Klenow, Tyler D.; Kahle, Jason T.; Wernke, Matthew M.; Carey, Stephanie L.; Miro, Rebecca M.; Lura, Derek J.

    2016-01-01

    Use of the Genium microprocessor knee (MPK) system reportedly improves knee kinematics during walking and other functional tasks compared to other MPK systems. This improved kinematic pattern was observed when walking on different hill conditions and at different speeds. Given the improved kinematics associated with hill walking while using the Genium, a similar improvement in the symmetry of knee kinetics is also feasible. The purpose of this study was to determine if Genium MPK use would reduce the degree of asymmetry (DoA) of peak stance knee flexion moment compared to the C-Leg MPK in transfemoral amputation (TFA) patients. This study used a randomized experimental crossover of TFA patients using Genium and C-Leg MPKs (n = 20). Biomechanical gait analysis by 3D motion tracking with floor mounted force plates of TFA patients ambulating at different speeds on 5° ramps was completed. Knee moment DoA was significantly different between MPK conditions in the slow and fast uphill as well as the slow and self-selected downhill conditions. In a sample of high-functioning TFA patients, Genium knee system accommodation and use improved knee moment symmetry in slow speed walking up and down a five degree ramp compared with C-Leg. Additionally, the Genium improved knee moment symmetry when walking downhill at comfortable speed. These results likely have application in other patients who could benefit from more consistent knee function, such as older patients and others who have slower walking speeds. PMID:28066523

  19. Improvements in knee biomechanics during walking are associated with increased physical activity after total knee arthroplasty.

    PubMed

    Arnold, John B; Mackintosh, Shylie; Olds, Timothy S; Jones, Sara; Thewlis, Dominic

    2015-12-01

    Total knee arthroplasty (TKA) in people with knee osteoarthritis increases knee-specific and general physical function, but it has not been established if there is a relationship between changes in these elements of functional ability. This study investigated changes and relationships between knee biomechanics during walking, physical activity, and use of time after TKA. Fifteen people awaiting TKA underwent 3D gait analysis before and six months after surgery. Physical activity and use of time were determined in free-living conditions from a high resolution 24-h activity recall. After surgery, participants displayed significant improvements in sagittal plane knee biomechanics and improved their physical activity profiles, standing for 105 more minutes (p=0.001) and performing 64 min more inside chores on average per day (p=0.008). Changes in sagittal plane knee range of motion (ROM) and peak knee flexion positively correlated with changes in total daily energy expenditure, time spent undertaking moderate to vigorous physical activity, inside chores and passive transport (r=0.52-0.66, p=0.005-0.047). Restoration of knee function occurs in parallel and is associated with improvements in physical activity and use of time after TKA. Increased functional knee ROM is required to support improvements in total and context specific physical activity.

  20. EFFECTS OF THE GENIUM MICROPROCESSOR KNEE SYSTEM ON KNEE MOMENT SYMMETRY DURING HILL WALKING.

    PubMed

    Highsmith, M Jason; Klenow, Tyler D; Kahle, Jason T; Wernke, Matthew M; Carey, Stephanie L; Miro, Rebecca M; Lura, Derek J

    2016-09-01

    Use of the Genium microprocessor knee (MPK) system reportedly improves knee kinematics during walking and other functional tasks compared to other MPK systems. This improved kinematic pattern was observed when walking on different hill conditions and at different speeds. Given the improved kinematics associated with hill walking while using the Genium, a similar improvement in the symmetry of knee kinetics is also feasible. The purpose of this study was to determine if Genium MPK use would reduce the degree of asymmetry (DoA) of peak stance knee flexion moment compared to the C-Leg MPK in transfemoral amputation (TFA) patients. This study used a randomized experimental crossover of TFA patients using Genium and C-Leg MPKs (n = 20). Biomechanical gait analysis by 3D motion tracking with floor mounted force plates of TFA patients ambulating at different speeds on 5° ramps was completed. Knee moment DoA was significantly different between MPK conditions in the slow and fast uphill as well as the slow and self-selected downhill conditions. In a sample of high-functioning TFA patients, Genium knee system accommodation and use improved knee moment symmetry in slow speed walking up and down a five degree ramp compared with C-Leg. Additionally, the Genium improved knee moment symmetry when walking downhill at comfortable speed. These results likely have application in other patients who could benefit from more consistent knee function, such as older patients and others who have slower walking speeds.

  1. Determination of representative dimension parameter values of Korean knee joints for knee joint implant design.

    PubMed

    Kwak, Dai Soon; Tao, Quang Bang; Todo, Mitsugu; Jeon, Insu

    2012-05-01

    Knee joint implants developed by western companies have been imported to Korea and used for Korean patients. However, many clinical problems occur in knee joints of Korean patients after total knee joint replacement owing to the geometric mismatch between the western implants and Korean knee joint structures. To solve these problems, a method to determine the representative dimension parameter values of Korean knee joints is introduced to aid in the design of knee joint implants appropriate for Korean patients. Measurements of the dimension parameters of 88 male Korean knee joint subjects were carried out. The distribution of the subjects versus each measured parameter value was investigated. The measured dimension parameter values of each parameter were grouped by suitable intervals called the "size group," and average values of the size groups were calculated. The knee joint subjects were grouped as the "patient group" based on "size group numbers" of each parameter. From the iterative calculations to decrease the errors between the average dimension parameter values of each "patient group" and the dimension parameter values of the subjects, the average dimension parameter values that give less than the error criterion were determined to be the representative dimension parameter values for designing knee joint implants for Korean patients.

  2. Effect of knee sleeve on static and dynamic balance in patients with knee osteoarthritis.

    PubMed

    Chuang, Shih-Hung; Huang, Mao-Hsiung; Chen, Tien-Wen; Weng, Ming-Chang; Liu, Chin-Wei; Chen, Chia-Hsin

    2007-08-01

    Patients with knee osteoarthritis (OA) find that use of elastic knee sleeves gives them partial pain relief and a greater sense of joint stability. However, the scientific effects of knee OA patients wearing braces are unclear. The purpose of this study was to investigate the effects of knee sleeves on static and dynamic balance in knee OA patients. Fifty patients with knee OA were enrolled in the study and all subjects were randomly divided into two groups. Initially, subjects in group A did not wear a neoprene sleeve while receiving balance tests but then wore them to be re-tested. Subjects in group B did just the reverse procedure. In this investigation, an instrument (KAT 2000; Breg Inc., Vista, CA, USA), which quantified motor control performance of the lower extremities was used and balance scores from the KAT 2000 software were obtained. The results revealed that the scores of patients wearing braces were significantly lower than those of patients without braces (p < 0.05).The finding of this study demonstrated that knee OA patients wearing knee sleeves could experience increased balance ability in both static and dynamic conditions. The improvement might prevent knee OA patients from falling down and increase their sense of security during physical activities.

  3. Lockable Knee Brace Speeds Rehabilitation

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Marshall Space Flight Center develops key transportation and propulsion technologies for the Space Agency. The Center manages propulsion hardware and technologies of the space shuttle, develops the next generation of space transportation and propulsion systems, oversees science and hardware development for the International Space Station, manages projects and studies that will help pave the way back to the Moon, and handles a variety of associated scientific endeavors to benefit space exploration and improve life here on Earth. It is a large and diversified center, and home to a great wealth of design skill. Some of the same mechanical design skill that made its way into the plans for rocket engines and advanced propulsion at this Alabama-based NASA center also worked its way into the design of an orthotic knee joint that is changing the lives of people with weakened quadriceps.

  4. Arthroscopic lysis in knee arthrofibrosis.

    PubMed

    Vaquero, J; Vidal, C; Medina, E; Baena, J

    1993-01-01

    Arthrofibrosis continues to be a difficult complication in articular surgery on the knee. We present our experience in 21 cases of arthroscopic lysis as an alternative to mobilization under anesthesia. The technique begins with the liberation of the adhesions of the suprapatellar pouch, continues down both gutters, and ends with a cleaning of the notch where necessary. When a restriction of patellar mobility persists, we make a retinacular release. The results obtained are very satisfactory, with an average increase in the arc of mobility of 68 degrees. The average gain in mobility at 6 months is significantly greater than that achieved in the immediate postoperative period. Longer follow-up showed no improvement in range of motion after 6 months.

  5. Update management below knee intervention.

    PubMed

    Bosiers, M; Deloose, K; Verbist, J; Peeters, P

    2009-02-01

    The application of percutaneous techniques for the treatment of peripheral arterial occlusive disease (PAOD) has gained widespread interest over the last decade. Together with the development of new endovascular tools and with an increasing operator experience, the minimal invasive percutaneous therapy became first line therapy at many institutions. Patients with critical limb ischemia (CLI) due to infrapopliteal lesions are often no good candidates infra-geniculate bypass surgery (IBS), as they often present with prohibitive comorbidities, inadequate conduit, and lack of suitable distal targets for revascularization. Therefore, CLI patients due to blockage of below-the-knee (BTK) arteries are in benefit of the endovascular approach: it offers the advantages of local anesthesia, potentially reduced costs (even anticipating the need for reintervention in many patients), shorter hospital stays The current article provides an overview of the diagnosis and endovascular treatment strategies for infrapopliteal lesions in patients with CLI and gives recommendations for future infrapopliteal device technology advancements.

  6. NAVIGATION IN TOTAL KNEE ARTHROPLASTY

    PubMed Central

    da Mota e Albuquerque, Roberto Freire

    2015-01-01

    Navigation was the most significant advance in instrumentation for total knee arthroplasty over the last decade. It provides surgeons with a precision tool for carrying out surgery, with the possibility of intraoperative simulation and objective control over various anatomical and surgical parameters and references. Since the first systems, which were basically used to control the alignment of bone cutting referenced to the mechanical axis of the lower limb, many other surgical steps have been incorporated, such as component rotation, ligament balancing and arranging the symmetry of flexion and extension spaces, among others. Its efficacy as a precision tool with an effective capacity for promoting better alignment of the lower-limb axis has been widely proven in the literature, but the real value of optimized alignment and the impact of navigation on clinical results and the longevity of arthroplasty have yet to be established. PMID:27026979

  7. MRI based knee cartilage assessment

    NASA Astrophysics Data System (ADS)

    Kroon, Dirk-Jan; Kowalski, Przemyslaw; Tekieli, Wojciech; Reeuwijk, Els; Saris, Daniel; Slump, Cornelis H.

    2012-03-01

    Osteoarthritis is one of the leading causes of pain and disability worldwide and a major health problem in developed countries due to the gradually aging population. Though the symptoms are easily recognized and described by a patient, it is difficult to assess the level of damage or loss of articular cartilage quantitatively. We present a novel method for fully automated knee cartilage thickness measurement and subsequent assessment of the knee joint. First, the point correspondence between a pre-segmented training bone model is obtained with use of Shape Context based non-rigid surface registration. Then, a single Active Shape Model (ASM) is used to segment both Femur and Tibia bone. The surfaces obtained are processed to extract the Bone-Cartilage Interface (BCI) points, where the proper segmentation of cartilage begins. For this purpose, the cartilage ASM is trained with cartilage edge positions expressed in 1D coordinates at the normals in the BCI points. The whole cartilage model is then constructed from the segmentations obtained in the previous step. An absolute thickness of the segmented cartilage is measured and compared to the mean of all training datasets, giving as a result the relative thickness value. The resulting cartilage structure is visualized and related to the segmented bone. In this way the condition of the cartilage is assessed over the surface. The quality of bone and cartilage segmentation is validated and the Dice's coefficients 0.92 and 0.86 for Femur and Tibia bones and 0.45 and 0.34 for respective cartilages are obtained. The clinical diagnostic relevance of the obtained thickness mapping is being evaluated retrospectively. We hope to validate it prospectively for prediction of clinical outcome the methods require improvements in accuracy and robustness.

  8. Hyperextended Knee: Cause of Serious Injury?

    MedlinePlus

    ... www.clinicalkey.com. Accessed April 24, 2015. Brooks GP, et al. Treatment of knee injuries in the ... of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.org," "Mayo ...

  9. Is Running Bad for Your Knees?

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_162903.html Is Running Bad for Your Knees? Study suggests it may ... THURSDAY, Jan. 5, 2017 (HealthDay News) -- Everybody believes running can leave you sore and swollen, right? Well, ...

  10. Deciding to have knee or hip replacement

    MedlinePlus

    ... the hip In: Canale ST, Beaty JH, eds. Campbell's Operative Orthopaedics . 12th ed. Philadelphia, PA: Elsevier Mosby; ... the knee. In: Canale ST, Beaty JH, eds. Campbell's Operative Orthopaedics . 12th ed. Philadelphia, PA: Elsevier Mosby; ...

  11. Risks of hip and knee replacement

    MedlinePlus

    ... the hip In: Canale ST, Beaty JH, eds. Campbell's Operative Orthopaedics . 12th ed. Philadelphia, PA: Elsevier Mosby; ... the knee. In: Canale ST, Beaty JH, eds. Campbell's Operative Orthopaedics . 12th ed. Philadelphia, PA: Elsevier Mosby; ...

  12. Periprosthetic Knee Infection: Ten Strategies That Work

    PubMed Central

    Cavanaugh, Priscilla Ku; Diaz-Ledezma, Claudio

    2013-01-01

    Periprosthetic joint infection (PJI) is one of the most serious complications following total knee arthroplasty (TKA). The demand for TKA is rapidly increasing, resulting in a subsequent increase in infections involving knee prosthesis. Despite the existence of common management practices, the best approach for several aspects in the management of periprosthetic knee infection remains controversial. This review examines the current understanding in the management of the following aspects of PJI: preoperative risk stratification, preoperative antibiotics, preoperative skin preparation, outpatient diagnosis, assessing for infection in revision cases, improving culture utility, irrigation and debridement, one and two-stage revision, and patient prognostic information. Moreover, ten strategies for the management of periprosthetic knee infection based on available literature, and experience of the authors were reviewed. PMID:24368992

  13. American Association of Hip and Knee Surgeons

    MedlinePlus

    ... Programs Performance & Quality Practice Management FARE – AAHKS Foundation Partner With AAHKS AAHKS Committee Orientation AJRR 2016 Annual Report Hip and Knee Online Exam Page AAHKS Business Reports AAHKS Committee Orientation AAHKS News 2014 AAHKS ...

  14. Knee bone tumors: findings on conventional radiology*

    PubMed Central

    Andrade Neto, Francisco; Teixeira, Manuel Joaquim Diógenes; Araújo, Leonardo Heráclio do Carmo; Ponte, Carlos Eduardo Barbosa

    2016-01-01

    The knee is a common site for bone tumors, whether clinically painful or not. Conventional radiology has been established as the first line of investigation in patients with knee pain and can reveal lesions that often generate questions not only for the generalist physician but also for the radiologist or general orthopedist. History, image examination, and histopathological analysis compose the essential tripod of the diagnosis of bone tumors, and conventional radiology is an essential diagnostic tool in patients with knee pain. This pictorial essay proposes to depict the main conventional radiography findings of the most common bone tumors around the knee, including benign and malignant tumors, as well as pseudo-tumors. PMID:27403019

  15. Knee System Utilizing Personalized Solutions Instrumentation

    MedlinePlus

    ATTUNE® Knee System utilizing the TRUMATCH® Personalized Solutions Instrumentation Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2017 BroadcastMed, Inc. All rights reserved.

  16. Computational Poromechanics of Human Knee Joint

    NASA Astrophysics Data System (ADS)

    Kazemi, Mojtaba; Li, LePing

    2012-02-01

    Extensive computer modeling has been performed in the recent decade to investigate the mechanical response of the healthy and repaired knee joints. Articular cartilages and menisci have been commonly modeled as single-phase elastic materials in the previous 3D simulations. A comprehensive study considering the interplay of the collagen fibers and fluid pressurization in the tissues in situ remains challenging. We have developed a 3D model of the human knee accounting for the mechanical function of collagen fibers and fluid flow in the cartilages and menisci. An anatomically accurate structure of the human knee was used for this purpose including bones, articular cartilages, menisci and ligaments. The fluid pressurization in the femoral cartilage and menisci under combined creep loading was investigated. Numerical results showed that fluid flow and pressure in the tissues played an important role in the mechanical response of the knee joint. The load transfer in the joint was clearly seen when the fluid pressure was considered.

  17. Obesity May Not Compromise Knee Surgery Success

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_164282.html Obesity May Not Compromise Knee Surgery Success Results similar ... over 35, so it's unclear if more severe obesity might increase the risk of meniscal repair failure, ...

  18. Self-reported knee instability and activity limitations in patients with knee osteoarthritis: results of the Amsterdam osteoarthritis cohort.

    PubMed

    van der Esch, Martin; Knoop, Jesper; van der Leeden, Marike; Voorneman, Ramon; Gerritsen, Martijn; Reiding, Dick; Romviel, Suzanne; Knol, Dirk L; Lems, Willem F; Dekker, Joost; Roorda, Leo D

    2012-10-01

    The objective of this study was to evaluate whether self-reported knee instability is associated with activity limitations in patients with knee osteoarthritis (OA), in addition to knee pain and muscle strength. A cohort of 248 patients diagnosed with knee OA was examined. Self-reported knee instability was defined as the perception of any episode of buckling, shifting, or giving way of the knee in the past 3 months. Knee pain was assessed using a numeric rating scale, and knee extensor and flexor strength were measured using an isokinetic dynamometer. Activity limitations were measured by using the Western Ontario and McMasters Universities Osteoarthritis Index physical function questionnaire, the timed Get Up and Go, and the timed stair climbing and three questionnaires evaluating walking, climbing stairs, and rising from a chair. Other potential determinants of activity limitations were also collected, including joint proprioception, joint laxity, age, sex, body mass index (BMI), disease duration, and radiographic disease severity. Regression analyses evaluated the effect of adding self-reported knee instability to knee pain and muscle strength, when examining associations with the activity limitations measures. Self-reported knee instability was common (65 %) in this cohort of patients with knee OA. Analyses revealed that self-reported knee instability is significantly associated with activity limitations, even after controlling for knee pain and muscle strength. Joint proprioception, joint laxity, age, sex, BMI, duration of complaints, and radiographic severity did not confound the associations. In conclusion, self-reported knee instability is associated with activity limitations in patients with knee OA, in addition to knee pain and muscle strength. Clinically, self-reported knee instability should be assessed in addition to knee pain and muscle strength.

  19. Tantalum Cones in Revision Total Knee Arthroplasty.

    PubMed

    Kim, Eric G; Patel, Nirav K; Chughtai, Morad; Elmallah, Randa D K; Delanois, Ronald E; Harwin, Steven F; Mont, Michael A

    2016-11-01

    The best strategy to address large bony defects in revision total knee arthroplasty has yet to be determined. The relatively recent development of porous tantalum cones and their use to address massive bone loss in knee arthroplasty has shown promising short- and intermediate-term results. The purpose of this review is to present the current literature on: (1) basic science of porous tantalum, (2) classification and treatment for bone loss, (3) clinical results, and (4) evolution of newer generation cones.

  20. Multibody dynamic simulation of knee contact mechanics

    PubMed Central

    Bei, Yanhong; Fregly, Benjamin J.

    2006-01-01

    Multibody dynamic musculoskeletal models capable of predicting muscle forces and joint contact pressures simultaneously would be valuable for studying clinical issues related to knee joint degeneration and restoration. Current three-dimensional multi-body knee models are either quasi-static with deformable contact or dynamic with rigid contact. This study proposes a computationally efficient methodology for combining multibody dynamic simulation methods with a deformable contact knee model. The methodology requires preparation of the articular surface geometry, development of efficient methods to calculate distances between contact surfaces, implementation of an efficient contact solver that accounts for the unique characteristics of human joints, and specification of an application programming interface for integration with any multibody dynamic simulation environment. The current implementation accommodates natural or artificial tibiofemoral joint models, small or large strain contact models, and linear or nonlinear material models. Applications are presented for static analysis (via dynamic simulation) of a natural knee model created from MRI and CT data and dynamic simulation of an artificial knee model produced from manufacturer’s CAD data. Small and large strain natural knee static analyses required 1 min of CPU time and predicted similar contact conditions except for peak pressure, which was higher for the large strain model. Linear and nonlinear artificial knee dynamic simulations required 10 min of CPU time and predicted similar contact force and torque but different contact pressures, which were lower for the nonlinear model due to increased contact area. This methodology provides an important step toward the realization of dynamic musculoskeletal models that can predict in vivo knee joint motion and loading simultaneously. PMID:15564115

  1. Knee Instability and Basic and Advanced Function Decline in Persons with Knee Osteoarthritis

    PubMed Central

    Sharma, Leena; Chmiel, Joan S.; Almagor, Orit; Moisio, Kirsten; Chang, Alison H.; Belisle, Laura; Zhang, Yunhui; Hayes, Karen W.

    2015-01-01

    Objective Manifestations of instability in knee OA include low overall knee confidence, low confidence that the knees will not buckle, buckling, and excessive motion during gait. Confidence and buckling may particularly influence activity choices, contributing to events leading to disability. Buckling is more likely to affect advanced than basic functional tasks. In this prospective, longitudinal study, we tested the hypotheses: overall knee confidence, buckling confidence, buckling, and frontal plane motion during gait are associated with advanced 2-year function outcome in persons with knee OA. Methods Persons with knee OA were queried about overall knee confidence (higher worse), buckling confidence, and knee buckling, and underwent quantitative gait analysis to quantify varus-valgus excursion and angular velocity. Physical function was assessed using the LLFDI Basic and Advanced Lower Extremity Domain scores. Logistic regression was used to evaluate the relationship between baseline instability measures and baseline-to-2-year function outcome, adjusting for potential confounders. Results 212 persons (mean age 64.6 years, 76.9% women) comprised the sample. Buckling was significantly associated with poor advanced (adjusted OR 2.08, 95% CI: 1.03–4.20) but not basic function outcome. Overall knee confidence was significantly associated with advanced outcome (adjusted OR 1.65, 95% CI: 1.01–2.70), while associations between buckling confidence and both outcomes approached significance. Neither varus-valgus excursion nor angular velocity during gait was associated with either outcome. Conclusion Knee buckling and confidence were each associated with poor 2-year advanced function outcome. Current treatment does not address these modifiable factors; interventions to address them may improve outcome in knee OA. PMID:25732594

  2. Injury risk curves for the skeletal knee-thigh-hip complex for knee-impact loading.

    PubMed

    Rupp, Jonathan D; Flannagan, Carol A C; Kuppa, Shashi M

    2010-01-01

    Injury risk curves for the skeletal knee-thigh-hip (KTH) relate peak force applied to the anterior aspect of the flexed knee, the primary source of KTH injury in frontal motor-vehicle crashes, to the probability of skeletal KTH injury. Previous KTH injury risk curves have been developed from analyses of peak knee-impact force data from studies where knees of whole cadavers were impacted. However, these risk curves either neglect the effects of occupant gender, stature, and mass on KTH fracture force, or account for them using scaling factors derived from dimensional analysis without empirical support. A large amount of experimental data on the knee-impact forces associated with KTH fracture are now available, making it possible to estimate the effects of subject characteristics on skeletal KTH injury risk by statistically analyzing empirical data. Eleven studies were identified in the biomechanical literature in which the flexed knees of whole cadavers were impacted. From these, peak knee-impact force data and the associated subject characteristics were reanalyzed using survival analysis with a lognormal distribution. Results of this analysis indicate that the relationship between peak knee-impact force and the probability of KTH fracture is a function of age, total body mass, and whether the surface that loads the knee is rigid. Comparisons between injury risk curves for the midsize adult male and small adult female crash test dummies defined in previous studies and new risk curves for these sizes of occupants developed in this study suggest that previous injury risk curves generally overestimate the likelihood of KTH fracture at a given peak knee-impact force. Future work should focus on defining the relationships between impact force at the human knee and peak axial compressive forces measured by load cells in the crash test dummy KTH complex so that these new risk curves can be used with ATDs.

  3. Quantifying knee mechanics during balance training exercises.

    PubMed

    Benson, Lauren C; Almonroeder, Thomas G; O'Connor, Kristian M

    2017-01-01

    Patellofemoral pain (PFP) is common among runners and those recovering from anterior cruciate ligament reconstruction. Training programs designed to prevent or treat injuries often include balance training, although balance interventions have been reported to coincide with more knee injuries. Knowledge of the effect of balance exercises on knee mechanics may be useful when designing training programs. High knee abduction moment has been implicated in the development of PFP, and imbalance between vastus lateralis (VL) and vastus medialis oblique (VMO) may contribute to patellofemoral stress. The purpose was to quantify knee abduction moment and vasti muscle activity during balance exercises. Muscle activity of VMO and VL, three-dimensional lower-extremity kinematics, and ground reaction forces of healthy recreational athletes (12M, 13F) were recorded during five exercises. Peak knee abduction moment, ratio of VMO:VL activity, and delay in onset of VMO relative to VL were quantified for each exercise. The influence of sex and exercise on each variable was determined using a mixed-model ANOVA. All analyses indicated a significant main effect of exercise, p<0.05. Follow-up comparisons showed low peak knee abduction moment and high VMO:VL ratio for the task with anterior-posterior motion. Delay of VMO relative to VL was similar among balance board tasks.

  4. Arthroscopic treatment of the septic knee.

    PubMed

    Smith, M J

    1986-01-01

    Pyarthrosis of the knee was treated in 30 patients by arthroscopic decompression and lavage, coupled with parenteral and oral antibiotics. There were 21 men and nine women patients whose ages ranged from 6 months to 65 years of age. Twenty-two patients were considered to have a hematogenous origin as a cause of their pyarthrosis, and eight were caused by penetrating trauma. Twenty-eight of these patients had the onset of symptoms within 72 h prior to arthroscopy. Two adults had the onset of their symptoms 1 week prior to treatment. Follow-up has ranged from 6 months to 5 years. Staphylococcus aureus was cultured in 20 knees, Streptococcus pneumonia in three knees, Haemophilus influenzae in four knees, and Neisseria gonorrhoeae in one knee. The average hospital stay among 22 children aged 12 years or younger was 3.50 days. The other eight patients had an average hospital stay of 9.50 days. Three adults with diabetes and other medical problems, such as renal failure, had an average hospital stay of 17.33 days. Excellent results were obtained in 28 (93.3%) of 30 patients and good results were obtained in two (6.7%) of 30 patients. There were no poor results or recurrences, and no cases of osteomyelitis occurred. This method of treatment markedly reduces the morbidity and hospital stay of patients with a septic knee.

  5. Associations of knee muscle force, bone malalignment, and knee-joint laxity with osteoarthritis in elderly people

    PubMed Central

    Nakagawa, Kazumasa; Maeda, Misako

    2017-01-01

    [Purpose] From the viewpoint of prevention of knee osteoarthritis, the aim of this study was to verify how muscle strength and joint laxity are related to knee osteoarthritis. [Subjects and Methods] The study subjects consisted of 90 community-dwelling elderly people aged more than 60 years (22 males, 68 females). Femorotibial angle alignment, knee joint laxity, knee extensors and flexor muscle strengths were measured in all subjects. In addition, the subjects were divided into four groups based on the presence of laxity and knee joint deformation, and the muscle strength values were compared. [Results] There was no significant difference in knee extensor muscle strength among the four groups. However, there was significant weakness of the knee flexor muscle in the group with deformation and laxity was compared with the group without deformation and laxity. [Conclusion] Decreased knee flexor muscle strengths may be involved in knee joint deformation. The importance of muscle strength balance was also considered. PMID:28356631

  6. Associations of knee muscle force, bone malalignment, and knee-joint laxity with osteoarthritis in elderly people.

    PubMed

    Nakagawa, Kazumasa; Maeda, Misako

    2017-03-01

    [Purpose] From the viewpoint of prevention of knee osteoarthritis, the aim of this study was to verify how muscle strength and joint laxity are related to knee osteoarthritis. [Subjects and Methods] The study subjects consisted of 90 community-dwelling elderly people aged more than 60 years (22 males, 68 females). Femorotibial angle alignment, knee joint laxity, knee extensors and flexor muscle strengths were measured in all subjects. In addition, the subjects were divided into four groups based on the presence of laxity and knee joint deformation, and the muscle strength values were compared. [Results] There was no significant difference in knee extensor muscle strength among the four groups. However, there was significant weakness of the knee flexor muscle in the group with deformation and laxity was compared with the group without deformation and laxity. [Conclusion] Decreased knee flexor muscle strengths may be involved in knee joint deformation. The importance of muscle strength balance was also considered.

  7. Nonuniform Weakness in the Paretic Knee and Compensatory Strength Gains in the Nonparetic Knee Occurs after Stroke

    PubMed Central

    Lomaglio, Melanie J.; Eng, Janice J.

    2015-01-01

    Background This study was designed to quantify torque production at different joint angles in the paretic and non-paretic knee joints of individuals with stroke. Methods Extension and flexion torques were measured at 6 angles of the knee joint and normalized to peak torque in 19 subjects with stroke and 19 controls. Results Paretic knee extension torque was lower than controls when the knee was positioned near extension. In contrast, nonparetic knee extension and flexion torques were higher than controls when the knee was positioned near full flexion. Conclusions The paretic knee extensors demonstrated exaggerated weakness at short muscle lengths and the nonparetic knee extensors and flexors demonstrated selective strength gains. Clinicians should therefore consider paretic knee extensor strengthening near full extension and promote symmetrical use of the legs to prevent compensatory overuse of the non-paretic leg. PMID:18946213

  8. Effect of center of pressure modulation on knee adduction moment in medial compartment knee osteoarthritis.

    PubMed

    Haim, Amir; Wolf, Alon; Rubin, Guy; Genis, Yulya; Khoury, Mona; Rozen, Nimrod

    2011-11-01

    The knee adduction moment (KAM) provides a major contribution to the elevated load in the medial compartment of the knee. An abnormally high KAM has been linked with the progression of knee osteoarthritis (OA). Footwear-generated biomechanical manipulations reduce the magnitude of this moment by conveying a more laterally shifted trajectory of the foot's center of pressure (COP), reducing the distance between the ground reaction force and the center of the knee joint, thus lowering the magnitude of the torque. We sought to examine the outcome of a COP shift in a cohort of female patients suffering from medial knee OA. Twenty-two female patients suffering from medial compartment knee OA underwent successive gait analysis testing and direct pedobarographic examination of the COP trajectory with a foot-worn biomechanical device allowing controlled manipulation of the COP. Modulation of the COP coronal trajectory from medial to lateral offset resulted in a significant reduction of the KAM. This trend was demonstrated in subjects with mild-to-moderate OA and in patients suffering from severe stages of the disease. Our results indicate that controlled manipulation of knee coronal kinetics in individuals suffering from medial knee OA can be facilitated by customized COP modification.

  9. 49 CFR 572.126 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... percent for at least four hours prior to a test. (2) Mount the test material and secure it to a rigid test... 49 Transportation 7 2014-10-01 2014-10-01 false Knees and knee impact test procedure. 572.126... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES...

  10. 49 CFR 572.176 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 70 percent for at least four hours prior to a test. (2) Mount the test material and secure it to a... 49 Transportation 7 2012-10-01 2012-10-01 false Knees and knee impact test procedure. 572.176... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST...

  11. 49 CFR 572.136 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the test material and secure it to a rigid test fixture as shown in Figure O5. No part of the foot or... 49 Transportation 7 2011-10-01 2011-10-01 false Knees and knee impact test procedure. 572.136... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST...

  12. 49 CFR 572.176 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 70 percent for at least four hours prior to a test. (2) Mount the test material and secure it to a... 49 Transportation 7 2014-10-01 2014-10-01 false Knees and knee impact test procedure. 572.176... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST...

  13. 49 CFR 572.136 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the test material and secure it to a rigid test fixture as shown in Figure O5. No part of the foot or... 49 Transportation 7 2014-10-01 2014-10-01 false Knees and knee impact test procedure. 572.136... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST...

  14. 49 CFR 572.136 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the test material and secure it to a rigid test fixture as shown in Figure O5. No part of the foot or... 49 Transportation 7 2013-10-01 2013-10-01 false Knees and knee impact test procedure. 572.136... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST...

  15. 49 CFR 572.126 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... percent for at least four hours prior to a test. (2) Mount the test material and secure it to a rigid test... 49 Transportation 7 2013-10-01 2013-10-01 false Knees and knee impact test procedure. 572.126... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES...

  16. 49 CFR 572.126 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... percent for at least four hours prior to a test. (2) Mount the test material and secure it to a rigid test... 49 Transportation 7 2012-10-01 2012-10-01 false Knees and knee impact test procedure. 572.126... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES...

  17. 49 CFR 572.126 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... percent for at least four hours prior to a test. (2) Mount the test material and secure it to a rigid test... 49 Transportation 7 2010-10-01 2010-10-01 false Knees and knee impact test procedure. 572.126... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES...

  18. 49 CFR 572.136 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the test material and secure it to a rigid test fixture as shown in Figure O5. No part of the foot or... 49 Transportation 7 2010-10-01 2010-10-01 false Knees and knee impact test procedure. 572.136... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST...

  19. 49 CFR 572.176 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 70 percent for at least four hours prior to a test. (2) Mount the test material and secure it to a... 49 Transportation 7 2013-10-01 2013-10-01 false Knees and knee impact test procedure. 572.176... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST...

  20. 49 CFR 572.136 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the test material and secure it to a rigid test fixture as shown in Figure O5. No part of the foot or... 49 Transportation 7 2012-10-01 2012-10-01 false Knees and knee impact test procedure. 572.136... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST...

  1. 49 CFR 572.126 - Knees and knee impact test procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... percent for at least four hours prior to a test. (2) Mount the test material and secure it to a rigid test... 49 Transportation 7 2011-10-01 2011-10-01 false Knees and knee impact test procedure. 572.126... TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES...

  2. [Knee joint distraction: a solution for young patients with osteoarthritis of the knee?

    PubMed

    Piscaer, T M; van der Jagt, O P; Gosens, T

    2016-01-01

    The current treatment for patients with end-stage generalised osteoarthritis of the knee is total knee replacement. In a recent paper in Plos One the authors examined an alternative approach, namely knee joint distraction. On the basis of a model, they claim that this treatment can postpone total knee replacement for about 20 years. This would reduce the costs for the healthcare services and improve quality of life for these patients. Although these claims seem promising, the model is only based on extrapolations of short-term results of small cohort studies. Furthermore, concerns about potential complications, e.g. osteomyelitis following pin-tract infections, are not mentioned. Further high quality studies in knee joint distraction are needed to prove its long-term efficacy and safety before this procedure can be implemented in standard clinical care.

  3. Position controlled Knee Rehabilitation Orthotic Device for Patients after Total Knee Replacement Arthroplasty

    NASA Astrophysics Data System (ADS)

    Wannaphan, Patsiri; Chanthasopeephan, Teeranoot

    2016-11-01

    Knee rehabilitation after total knee replacement arthroplasty is essential for patients during their post-surgery recovery period. This study is about designing one degree of freedom knee rehabilitation equipment to assist patients for their post-surgery exercise. The equipment is designed to be used in sitting position with flexion/extension of knee in sagittal plane. The range of knee joint motion is starting from 0 to 90 degrees angle for knee rehabilitation motion. The feature includes adjustable link for different human proportions and the torque feedback control at knee joint during rehabilitation and the control of flexion/extension speed. The motion of the rehabilitation equipment was set to move at low speed (18 degrees/sec) for knee rehabilitation. The rehabilitation link without additional load took one second to move from vertical hanging up to 90° while the corresponding torque increased from 0 Nm to 2 Nm at 90°. When extra load is added, the link took 1.5 seconds to move to 90° The torque is then increased from 0 Nm to 4 Nm. After a period of time, the speed of the motion can be varied. User can adjust the motion to 40 degrees/sec during recovery activity of the knee and users can increase the level of exercise or motion up to 60 degrees/sec to strengthen the muscles during throughout their rehabilitation program depends on each patient. Torque control is included to prevent injury. Patients can use the equipment for home exercise to help reduce the number of hospital visit while the patients can receive an appropriate therapy for their knee recovery program.

  4. Exercise and knee osteoarthritis: benefit or hazard?

    PubMed Central

    Bosomworth, Neil J.

    2009-01-01

    ABSTRACT OBJECTIVE To determine whether physical exercise constitutes a benefit or a risk in the development and progression of knee osteoarthritis. QUALITY OF EVIDENCE MEDLINE, EMBASE, DARE, ACP Journal Club, and Cochrane databases were searched from registry inception to January 2009 using MeSH headings or text words, including osteoarthritis, arthritis and knee and exercise, physical training, and run. Reference lists from retrieved articles, citation listings when available, and related articles suggested in PubMed were also evaluated. For individuals without osteoarthritis, strong level II evidence was found (limited by problems with blinding and randomization); for those with pre-existing knee osteoarthritis, robust level I evidence was available. MAIN MESSAGE Knee osteoarthritis is a major contributor to disability in seniors, and patients have expressed concern that continued exercise might lead to knee symptoms in later years. Studies done on subjects self-selected for exercise and followed for substantial periods of time show no evidence of accelerated development of osteoarthritis, provided injury is avoided. Further, there is good evidence for reduced pain and disability with exercise in this cohort compared with controls. Patients with established osteoarthritis are shown to derive uniform benefit to physical functioning, with reduction of pain and disability, using aerobic, muscle strengthening, aquatic, or physiotherapy-based exercise modalities. CONCLUSION Provided trauma is avoided, moderate exercise does not lead to acceleration of knee osteoarthritis, whether or not there is evidence of pre-existing disease. In either case there appears to be improved physical functioning and reduction of pain and disability in those who exercise. It is likely that exercise interventions are underused in the management of established knee osteoarthritis symptoms. PMID:19752252

  5. Functional state of knee arthritis patients and related factors

    PubMed Central

    Lee, Jiyeon; Kim, Jung-Hee; Chung, EunJung; Lee, Byoung-Hee

    2017-01-01

    [Purpose] The objective of this study is to provide a direction for efficient management of arthritis through the analysis of multiple factors related to the functional state of patients. [Subjects and Methods] The Visual Analog Scale, Knee Society Knee Score & Function Score, Hospital for Special Surgery, Short Form-36 Health Survey and Western Ontario McMaster Universities Osteoarthritis Index for a total of 135 patients with knee arthritis were determined with a survey. [Results] There is a significant correlation between age, pain, Knee Society Knee Score, Hospital for Special Surgery, Knee Society Function Score, and Western Ontario McMaster Universities Osteoarthritis Index score. [Conclusion] It is necessary to improve the factors that affect knee function and quality of life, and a study on knee joint muscle strength is suggested as a follow-up study. PMID:28265166

  6. Techniques for assessing knee joint pain in arthritis

    PubMed Central

    Neugebauer, Volker; Han, Jeong S; Adwanikar, Hita; Fu, Yu; Ji, Guangchen

    2007-01-01

    The assessment of pain is of critical importance for mechanistic studies as well as for the validation of drug targets. This review will focus on knee joint pain associated with arthritis. Different animal models have been developed for the study of knee joint arthritis. Behavioral tests in animal models of knee joint arthritis typically measure knee joint pain rather indirectly. In recent years, however, progress has been made in the development of tests that actually evaluate the sensitivity of the knee joint in arthritis models. They include measurements of the knee extension angle struggle threshold, hind limb withdrawal reflex threshold of knee compression force, and vocalizations in response to stimulation of the knee. A discussion of pain assessment in humans with arthritis pain conditions concludes this review. PMID:17391515

  7. Joint Line Reconstruction in Navigated Total Knee Arthroplasty Revision

    ClinicalTrials.gov

    2012-05-16

    Revision Total Knee Arthroplasty Because of; Loosening; Instability; Impingement; or Other Reasons Accepted as Indications for TKA Exchange.; The Focus is to Determine the Precision of Joint Line Restoration in Navigated vs. Conventional Revision Total Knee Arthroplasty

  8. Getting your home ready - knee or hip surgery

    MedlinePlus

    ... if it is placed in a bathtub. Avoiding Falls Keep tripping hazards out of your home. Remove ... Knee arthroscopy - discharge Knee joint replacement - discharge Preventing falls - what to ask your doctor Taking care of ...

  9. Editorial Commentary: Knee Hyaluronic Acid Viscosupplementation Reduces Osteoarthritis Pain.

    PubMed

    Lubowitz, James H

    2015-10-01

    In contrast to the AAOS knee osteoarthritis guidelines, systematic review of overlapping meta-analyses shows that viscosupplementation with intra-articular hyaluronic acid injection reduces knee osteoarthritis pain and improves function according to the highest level of evidence.

  10. Knee Replacement Doesn't Always Pay, Researchers Say

    MedlinePlus

    ... gov/news/fullstory_164320.html Knee Replacement Doesn't Always Pay, Researchers Say Less pain to begin ... 28, 2017 (HealthDay News) -- Knee replacement surgery isn't always a game changer, according to a new ...

  11. Hip or knee replacement - before - what to ask your doctor

    MedlinePlus

    ... PA: Elsevier Mosby; 2012:chap 7. Read More Hip joint replacement Hip pain Knee joint replacement Knee pain ... joint replacement - discharge Taking care of your new hip joint Review Date 3/5/2015 Updated by: C. ...

  12. Hip or knee replacement - after - what to ask your doctor

    MedlinePlus

    ... PA: Elsevier Mosby; 2012:chap 7. Read More Hip joint replacement Hip pain Knee joint replacement Knee pain ... joint replacement - discharge Taking care of your new hip joint Review Date 3/5/2015 Updated by: C. ...

  13. Post-traumatic chylous knee effusion.

    PubMed

    Tahara, Masamichi; Katsumi, Akira; Akazawa, Tsutomu; Otsuka, Yoshinori; Kitahara, Sota

    2011-03-01

    Chylous joint effusion is a rare condition in which synovial fluids containing large amounts of lipids take on a milky appearance as a result. We report on a 19-year-old male patient with posttraumatic chylous knee effusion. Several days after striking his knee against the ground because of a traffic accident, his left knee showed obvious swelling. Aspiration of his knee was performed, yielding 70ml of purulent-appearing fluid. To distinguish this condition from purulent or tuberculosis arthritis, arthroscopic biopsy and debridement were performed. Arthroscopic examination visualized distinctive yellow-white soft lesions covering much of the joint capsule, resembling a cobweb. Tissue cultures for bacteria were negative. Pathologically, we identified clusters of xanthoma cells with fibrin exudation due to disruption of the synovium and intra-articular fat pad necrosis. Centrifuging the aspiration fluid yielded a thick creamy lipid layer as the supernatant. A fresh drop preparation showed that the specimen contained innumerable fat globules, which stained red with oil red O stain. The patient was able to walk without difficulty or further swelling of his knee at the end of the second postoperative week. Posttraumatic chylous effusion is self-limited. Purulent arthritis or tuberculosis arthritis, however, should still be the presumptive diagnosis in such cases. Arthroscopic irrigation and debridement should be considered for these traumatic cases to confirm diagnosis and to speed up recovery.

  14. Post-traumatic knee stiffness: surgical techniques.

    PubMed

    Pujol, N; Boisrenoult, P; Beaufils, P

    2015-02-01

    Post-traumatic knee stiffness and loss of range of motion is a common complication of injuries to the knee area. The causes of post-traumatic knee stiffness can be divided into flexion contractures, extension contractures, and combined contractures. Post-traumatic stiffness can be due to the presence of dense intra-articular adhesions and/or fibrotic transformation of peri-articular structures. Various open and arthroscopic surgical treatments are possible. A precise diagnosis and understanding of the pathology is mandatory prior to any surgical treatment. Failure is imminent if all pathologies are not addressed correctly. From a general point of view, a flexion contracture is due to posterior adhesions and/or anterior impingement. On the other hand, extension contractures are due to anterior adhesions and/or posterior impingement. This overview will describe the different modern surgical techniques for treating post-traumatic knee stiffness. Any bony impingements must be treated before soft tissue release is performed. Intra-articular stiff knees with a loss of flexion can be treated by an anterior arthroscopic arthrolysis. Extra-articular pathology causing a flexion contracture can be treated by open or endoscopic quadriceps release. Extension contractures can be treated by arthroscopic or open posterior arthrolysis. Postoperative care (analgesia, rehabilitation) is essential to maintaining the range of motion obtained intra-operatively.

  15. Knee injuries in women collegiate rugby players.

    PubMed

    Levy, A S; Wetzler, M J; Lewars, M; Laughlin, W

    1997-01-01

    We evaluated the prevalence and patterns of knee injuries in 810 women collegiate rugby players. Injuries that resulted in players missing at least one game were recorded and a questionnaire was used to delineate players' rugby and knee injury history. There were 76 total knee injuries in 58,296 exposures. This resulted in a 1.3 knee injury rate per 1000 exposures. Twenty-one anterior cruciate ligament tears were reported for a 0.36 incidence per 1000 exposures. Other injuries included meniscal tears (25), medical collateral ligament sprains (23), patellar dislocations (5), and posterior cruciate ligament tears (2). Sixty-one percent of the medial collateral ligament sprains occurred in rugby forwards and 67% of anterior cruciate ligament tears occurred in rugby backs. All other injuries occurred with equal frequency in backs and forwards. This study demonstrates that knee injury rates in women's collegiate rugby are similar to those reported for other women's collegiate sports. The overall rate of anterior cruciate ligament injury in women's rugby, however, is slightly higher than that reported for women soccer and basketball players.

  16. Model-Based Estimation of Knee Stiffness

    PubMed Central

    Pfeifer, Serge; Vallery, Heike; Hardegger, Michael; Riener, Robert; Perreault, Eric J.

    2013-01-01

    During natural locomotion, the stiffness of the human knee is modulated continuously and subconsciously according to the demands of activity and terrain. Given modern actuator technology, powered transfemoral prostheses could theoretically provide a similar degree of sophistication and function. However, experimentally quantifying knee stiffness modulation during natural gait is challenging. Alternatively, joint stiffness could be estimated in a less disruptive manner using electromyography (EMG) combined with kinetic and kinematic measurements to estimate muscle force, together with models that relate muscle force to stiffness. Here we present the first step in that process, where we develop such an approach and evaluate it in isometric conditions, where experimental measurements are more feasible. Our EMG-guided modeling approach allows us to consider conditions with antagonistic muscle activation, a phenomenon commonly observed in physiological gait. Our validation shows that model-based estimates of knee joint stiffness coincide well with experimental data obtained using conventional perturbation techniques. We conclude that knee stiffness can be accurately estimated in isometric conditions without applying perturbations, which presents an important step towards our ultimate goal of quantifying knee stiffness during gait. PMID:22801482

  17. Knee alignment in professional tennis players.

    PubMed

    Maquirriain, Javier

    2002-01-01

    This study determined lower-limb alignment and knee geometry in professional tennis players and compared the data with those from nonathletic individuals. Twenty-four radiographs from 12 asymptomatic players (mean age: 23.4+/-3.8 years) were prospectively studied. The three angles most useful for describing limb alignment and knee geometry in the coronal plane were measured: hip-knee-ankle, condylar-hip, and plateau-ankle. The condylar-plateau angle, frontal foot rotation angle, and the relationship between the mechanical axis and tibial plateau also were calculated. Varus limb alignment was predominant and the mechanical axis passed medially through the knee center; there was increased valgus inclination of the distal femur, varus angulation of the tibial plateau, near parallel alignment of the joint, and exaggerated external foot rotation. Hip-knee-ankle, condylar-hip, plateau-ankle, and frontal foot rotation angles were significantly different (P<.05, two-tailed t test) from previously reported angles of nonathletic individuals. Variations, probably due to repetitive dynamic demands imposed on lower limbs from an early age, seem to involve both femoral condyles and proximal tibial metaphyses, maintaining normal parallel joint alignment.

  18. [The acute knee injury - practical considerations].

    PubMed

    Bouaicha, Samy

    2014-04-09

    The acute knee injury represents one of the most common reasons to visit a general practitioner or an emergency department in a hospital. The initial assessment of an acute knee injury usually is affected by severe swelling, pain and a significant lack of motion. Conventional radiographs in three planes may provide additional information to limit the differential diagnosis. A clinical re-evaluation after five to ten days usually allows proper functional testing and therefore correct diagnosis in the majority of cases can be made. With suspicious clinical findings, MRI may be helpful to evaluate ligamentous, meniscal and cartilaginous structures. Femoro-tibial knee dislocation represents the most harmful acute knee injury and needs to be further evaluated and treated in an adequate medical institution in every suspicious case. Rapid vascular diagnostic with (CT)-angiography is crucial. Behind a multi-ligament injury of the knee a spontaneously reduced dislocation may hide and proper neuro-vascular exam therefore is mandatory in every patient. When fracture, blocking and major instability can be excluded at initial assessment, there is usually no need for any acute surgical intervention and initial conservative treatment may be conducted on an out-patient basis for most of the patients. Priority of surgical treatment depends on the injury pattern and delayed intervention with a pre-habilitative phase may be beneficial for certain pathologies.

  19. Effects of Hata Yoga on Knee Osteoarthritis

    PubMed Central

    Ghasemi, Gholam A; Golkar, Ainaz; Marandi, Sayyd M

    2013-01-01

    Background: The purpose of this research was to study the effects of 8 weeks of Hata yoga exercises on women with knee osteoarthritis. Studies about effects of Yoga on different chronic diseases show that these exercises have positive effects on chronic diseases. As knee osteoarthritis is very common among middle age women we decided to measure effectiveness of these exercises on knee osteoarthritis. Methods: Sample included 30 women with knee osteoarthritis who voluntarily participated in this semi-experimental study and were divided into a control group (15) and a yoga group (15). The yoga group received 60 minutes sessions of Hata yoga, 3 times a week and for 8 weeks. Pain, symptoms, daily activities, sports and spare-time activities, and quality of life were respectively measured by Visual Analog Scale (VAS) and Knee injury and Osteoarthritis Outcome Scale (KOOS) questionnaire. The Analysis of Variance (ANOVA) method for repetitive data was used to analyze the results (P = 0.05). Results: Findings showed that pain and symptoms were significantly decreased and scores of daily activities, sports, spare-time activities, and quality of life were significantly increased in the yoga group. Conclusions: It seems that yoga can be used as a conservative treatment besides usual treatments and medications to improve the condition of people with osteoarthritis. PMID:23717763

  20. Cooling Does Not Affect Knee Proprioception

    PubMed Central

    Ozmun, John C.; Thieme, Heather A.; Ingersoll, Christopher D.; Knight, Kenneth L.

    1996-01-01

    The effect of cooling on proprioception of the knee has not been studied extensively. In this study, we investigated the movement reproduction (timing and accuracy) aspect of proprioception. Subjects were tested under two conditions: a 20-minute application of ice and control. Proprioceptive accuracy and timing were measured by passively moving the knee, then comparing the subject's active reproduction of the passive movement. Subjects were blindfolded, then tested in three sectors of the knee's range of motion: 90° to 60°, 60° to 30°, and 30° to full extension. Ice application had no apparent effect on the subject's ability to perform accurate movement reproductions in the sectors tested. However, accuracy of the subject's final angle reproduction varied between the sectors as did the total time of the movement. One possible explanation for the difference between sectors is that different receptors are active at different points in the knee's range of motion. We conclude that cooling the knee joint for 20 minutes does not have an adverse effect on proprioception. PMID:16558379

  1. Cooling does not affect knee proprioception.

    PubMed

    Ozmun, J C; Thieme, H A; Ingersoll, C D; Knight, K L

    1996-01-01

    The effect of cooling on proprioception of the knee has not been studied extensively. In this study, we investigated the movement reproduction (timing and accuracy) aspect of proprioception. Subjects were tested under two conditions: a 20-minute application of ice and control. Proprioceptive accuracy and timing were measured by passively moving the knee, then comparing the subject's active reproduction of the passive movement. Subjects were blindfolded, then tested in three sectors of the knee's range of motion: 90 degrees to 60 degrees , 60 degrees to 30 degrees , and 30 degrees to full extension. Ice application had no apparent effect on the subject's ability to perform accurate movement reproductions in the sectors tested. However, accuracy of the subject's final angle reproduction varied between the sectors as did the total time of the movement. One possible explanation for the difference between sectors is that different receptors are active at different points in the knee's range of motion. We conclude that cooling the knee joint for 20 minutes does not have an adverse effect on proprioception.

  2. Improved Automatically Locking/Unlocking Orthotic Knee Joint

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce

    1995-01-01

    Proposed orthotic knee joint improved version of one described in "Automatically Locking/Unlocking Orthotic Knee Joint" (MFS-28633). Locks automatically upon initial application of radial force (wearer's weight) and unlocks automatically, but only when all loads (radial force and bending) relieved. Joints lock whenever wearer applies weight to knee at any joint angle between full extension and 45 degree bend. Both devices offer increased safety and convenience relative to conventional orthotic knee joints.

  3. Patellar Skin Surface Temperature by Thermography Reflects Knee Osteoarthritis Severity

    PubMed Central

    Denoble, Anna E.; Hall, Norine; Pieper, Carl F.; Kraus, Virginia B.

    2010-01-01

    Background: Digital infrared thermal imaging is a means of measuring the heat radiated from the skin surface. Our goal was to develop and assess the reproducibility of serial infrared measurements of the knee and to assess the association of knee temperature by region of interest with radiographic severity of knee Osteoarthritis (rOA). Methods: A total of 30 women (15 Cases with symptomatic knee OA and 15 age-matched Controls without knee pain or knee OA) participated in this study. Infrared imaging was performed with a Meditherm Med2000™ Pro infrared camera. The reproducibility of infrared imaging of the knee was evaluated through determination of intraclass correlation coefficients (ICCs) for temperature measurements from two images performed 6 months apart in Controls whose knee status was not expected to change. The average cutaneous temperature for each of five knee regions of interest was extracted using WinTes software. Knee x-rays were scored for severity of rOA based on the global Kellgren-Lawrence grading scale. Results: The knee infrared thermal imaging procedure used here demonstrated long-term reproducibility with high ICCs (0.50–0.72 for the various regions of interest) in Controls. Cutaneous temperature of the patella (knee cap) yielded a significant correlation with severity of knee rOA (R = 0.594, P = 0.02). Conclusion: The skin temperature of the patellar region correlated with x-ray severity of knee OA. This method of infrared knee imaging is reliable and as an objective measure of a sign of inflammation, temperature, indicates an interrelationship of inflammation and structural knee rOA damage. PMID:21151853

  4. Primary Total Knee Arthroplasty for Simple Distal Femoral Fractures in Elderly Patients with Knee Osteoarthritis

    PubMed Central

    Choi, Nam-Yong; Sohn, Jong-Min; Cho, Sung-Gil; Kim, Seung-Chan

    2013-01-01

    Purpose Primary total knee arthroplasty (TKA) can be an alternative method for treating distal femoral fractures in elderly patients with knee osteoarthritis. The purpose of this study was to evaluate the clinical and radiographic results in patients with knee osteoarthritis who underwent TKA with the Medial Pivot prosthesis for distal femoral fractures. Materials and Methods Eight displaced distal femoral fractures in 8 patients were treated with TKA using the Medial Pivot prosthesis and internal fixation. The radiographic and clinical evaluations were performed using simple radiographs and Hospital for Special Surgery (HSS) knee scores during a mean follow-up period of 49 months. Results All fractures united and the mean time to radiographic union was 15 weeks. The mean range of motion of the knee joint was 114.3° and the mean HSS knee score was 85.1 at the final follow-up. Conclusions Based on the radiographic and clinical results, TKA with internal fixation can be considered as an option for the treatment of simple distal femoral fractures in elderly patients who have advanced osteoarthritis of the knee with appropriate bone stock. PMID:24032103

  5. One-stage long-stem total knee arthroplasty for arthritic knees with stress fractures.

    PubMed

    Mittal, Amber; Bhosale, Pradeep B; Suryawanshi, Ashish V; Purohit, Shaligram

    2013-08-01

    PURPOSE. To evaluate the outcome of one-stage long-stem total knee arthroplasty (TKA) for patients with arthritic knees and tibiofemoral stress fractures. METHODS. Records of 11 men and 18 women aged 47 to 78 (mean, 66) years who underwent fixed-bearing posterior-stabilised TKA for osteoarthritis or rheumatoid arthritis of the knee with tibial (n=31) and femoral (n=3) stress fractures were reviewed. All the tibial fractures involved the proximal half. There were 7 associated fibular stress fractures. Of the 31 knees with tibial stress fractures, 26 and 5 manifested varus and valgus deformity, respectively. RESULTS. The mean follow-up period was 51 (range, 24-96) months. The mean tibiofemoral angle improved from 23.2 to 1.9 degrees varus. The mean Knee Society knee score improved from 38.5 (range, 15- 63) to 89.6 (range, 80-95) [p<0.05]. The mean Knee Society functional score improved from 25.5 (range, 0-40) to 86.5 (range, 60-100) [p<0.05]. All fractures were united at the last follow-up. No complications were encountered. CONCLUSION. One-stage long-stem TKA restores limb alignment and facilitates fracture healing, with excellent outcome.

  6. Relationship between knee alignment and the electromyographic activity of quadriceps muscles in patients with knee osteoarthritis

    PubMed Central

    Lim, Seong Hoon; Hong, Bo Young; Oh, Jee Hae; Lee, Jong In

    2015-01-01

    [Purpose] We evaluated the relationship between knee alignment and the electromyographic (EMG) activity of the vastus medialis (VM) to the vastus lateralis (VL) muscles in patients with knee osteoarthritis (OA) in a cross-sectional study. [Subjects and Methods] Forty subjects with knee OA were assessed by anatomic radiographic knee alignment and the VM/VL ratio was calculated. Surface EMG from both the VM and VL muscles were evaluated during maximal isometric contraction at 60° knee flexion. Simultaneously, peak quadriceps torque was assessed using an isokinetic dynamometer. Subjects were categorized into low, moderate, and high varus groups according to knee malalignment. The peak quadriceps torque and VM/VL ratio across groups, and their relationships with varus malalignment were analyzed. [Results] All subjects had medial compartment OA and the VM/VL ratio of all subjects was 1.31 ± 0.28 (mean ± SD). There were no significant differences in the peak quadriceps torque or VM/VL ratios across the groups nor were there any significant relationships with varus malalignment. [Conclusion] The VM/VL ratio and peak quadriceps torque were not associated with the severity of knee varus malalignment. PMID:25995602

  7. Variable stiffness actuated prosthetic knee to restore knee buckling during stance: a modeling study.

    PubMed

    Wentink, E C; Koopman, H F J M; Stramigioli, S; Rietman, J S; Veltink, P H

    2013-06-01

    Most modern intelligent knee prosthesis use dampers to modulate dynamic behavior and prevent excessive knee flexion, but they dissipate energy and do not assist in knee extension. Energy efficient variable stiffness control (VSA) can reduce the energy consumption yet effectively modulate the dynamic behavior and use stored energy during flexion to assist in subsequent extension. A principle design of energy efficient VSA in a prosthetic knee is proposed and analyzed for the specific case of rejection of a disturbed stance phase. The concept is based on the principle that the output stiffness of a spring can be changed without changing the energy stored in the elastic elements of the spring. The usability of this concept to control a prosthetic knee is evaluated using a model. Part of the stance phase of the human leg was modeled by a double pendulum. Specifically the rejection of a common disturbance of transfemoral prosthetic gait, an unlocked knee at heel strike, was evaluated. The ranges of spring stiffnesses were determined such that the angular characteristics of a normal stance phase were preserved, but disturbances could also be rejected. The simulations predicted that energy efficient VSA can be useful for the control of prosthetic knees.

  8. Lateral Knee Braces in Football: Do They Prevent Injury?

    ERIC Educational Resources Information Center

    Paulos, Lonnie E.; And Others

    1986-01-01

    The results of three recently presented clinical studies and a biomechanical study of the use of lateral knee braces to prevent knee injuries are reviewed. The results raise serious doubts about the efficacy of the preventive knee braces which are currently available. (Author/MT)

  9. Evaluation of total knee mechanics using a crouching simulator with a synthetic knee substitute.

    PubMed

    Lowry, Michael; Rosenbaum, Heather; Walker, Peter S

    2016-05-01

    Mechanical evaluation of total knees is frequently required for aspects such as wear, strength, kinematics, contact areas, and force transmission. In order to carry out such tests, we developed a crouching simulator, based on the Oxford-type machine, with novel features including a synthetic knee including ligaments. The instrumentation and data processing methods enabled the determination of contact area locations and interface forces and moments, for a full flexion-extension cycle. To demonstrate the use of the simulator, we carried out a comparison of two different total knee designs, cruciate retaining and substituting. The first part of the study describes the simulator design and the methodology for testing the knees without requiring cadaveric knee specimens. The degrees of freedom of the anatomic hip and ankle joints were reproduced. Flexion-extension was obtained by changing quadriceps length, while variable hamstring forces were applied using springs. The knee joint was represented by three-dimensional printed blocks on to which the total knee components were fixed. Pretensioned elastomeric bands of realistic stiffnesses passed through holes in the block at anatomical locations to represent ligaments. Motion capture of the knees during flexion, together with laser scanning and computer modeling, was used to reconstruct contact areas on the bearing surfaces. A method was also developed for measuring tibial component interface forces and moments as a comparative assessment of fixation. The method involved interposing Tekscan pads at locations on the interface. Overall, the crouching machine and the methodology could be used for many different mechanical measurements of total knee designs, adapted especially for comparative or parametric studies.

  10. The Knee Pain Map: Reliability of a Method to Identify Knee Pain Location and Pattern

    PubMed Central

    THOMPSON, LAURA R.; BOUDREAU, ROBERT; HANNON, MICHAEL J.; NEWMAN, ANNE B.; CHU, CONSTANCE R.; JANSEN, MARY; NEVITT, MICHAEL C.; KWOH, C. KENT

    2009-01-01

    Objective To describe the location and pattern of knee pain in patients with chronic, frequent knee pain using the Knee Pain Map, and to evaluate the inter- and intrarater reliability of the map. Methods A cohort of 799 participants from the University of Pittsburgh Osteoarthritis Initiative Clinical Center who had knee pain in the last 12 months were studied. Trained interviewers assessed and recorded participant-reported knee pain patterns into 8 local areas, 4 regional areas, or as diffuse. Inter- and intrarater reliability were assessed using Fleiss’ kappa. Results Participants most often reported localized (69%) followed by regional (14%) or diffuse (10%) knee pain. In those with localized pain, the most commonly reported locations were the medial (56%) and lateral (43%) joint lines. In those with regional pain, the most commonly reported regions were the patella (44%) and medial region (38%). There was excellent interrater reliability for the identification of localized and regional pain patterns (κ = 0.7–0.9 and 0.7–0.8, respectively). The interrater reliability for specific locations was also excellent (κ = 0.7–1.0) when the number of participants with pain in a location was >4. For regional pain, the kappa for specific regions varied from 0.7–1.0. Conclusion The majority of participants could identify the location of their knee pain, and trained interviewers could reliably record those locations. The variation in locations suggests that there are multiple sources of pain in knee OA. Additional studies are needed to determine whether specific knee pain patterns correlate with discrete pathologic findings on radiographs or magnetic resonance images. PMID:19479703

  11. Single Portal Knee Arthroscopy: 2015 Technique Update

    PubMed Central

    Cooper, Daniel E.

    2016-01-01

    A technique of single portal knee arthroscopy was reported in 2013. Using a parallel working cannula assembled to the arthroscope cannula, the instruments are passed into the joint in line with the arthroscope. The original technique video in Arthroscopy Techniques shows the use of a 25 mm tube assembly with a parallel portal through which biters and proximally bent cutter instruments are used to perform procedures in the knee. This 2015 technical update shows the current preferred and most versatile method of single portal knee arthroscopy using a parallel locking and rotating hub for passage of biters and double-bend cutters. The video shows adequate completion of a partial meniscectomy using only 1 portal. PMID:27073772

  12. [Knee joint pain with signs of arthrosis].

    PubMed

    Bender, T T A; Marinova, M; Radbruch, L; Conrad, R; Jobst, D; Mücke, M

    2017-03-14

    Chronic pain in the knee joint is most commonly caused by osteoarthritis, especially in elderly patients but can be due to other causes, such as rheumatoid arthritis. The diagnostics include an exact patient medical history and a clinical examination, which often already provide clear indications of the cause of the knee pain. Subsequently, further diagnostics can then be considered, such as radiological procedures and laboratory diagnostics. The treatment is determined by the cause and the individual patient and aims to reduce pain and to preserve the mobility of the joint. Generally, therapy consists of pain management and physiotherapy as well as alternative therapeutic procedures, mostly in combination. Proximal tibial opening wedge osteotomy can be useful; however, partial or total knee arthroplasty should only be considered when conservative treatment options have been exhausted.

  13. Robotic control in knee joint replacement surgery.

    PubMed

    Davies, B L; Rodriguez y Baena, F M; Barrett, A R W; Gomes, M P S F; Harris, S J; Jakopec, M; Cobb, J P

    2007-01-01

    A brief history of robotic systems in knee arthroplasty is provided. The place of autonomous robots is then discussed and compared to more recent 'hands-on' robotic systems that can be more cost effective. The case is made for robotic systems to have a clear justification, with improved benefits compared to those from cheaper navigation systems. A number of more recent, smaller, robot systems for knee arthroplasty are also described. A specific example is given of an active constraint medical robot, the ACROBOT system, used in a prospective randomized controlled trial of unicondylar robotic knee arthroplasty in which the robot was compared to conventional surgery. The results of the trial are presented together with a discussion of the need for measures of accuracy to be introduced so that the efficacy of the robotic surgery can be immediately identified, rather than have to wait for a number of years before long-term clinical improvements can be demonstrated.

  14. Knee ligament injury during lateral impact.

    PubMed

    Hearon, B F; Brinkley, J W; Raddin, J H; Fleming, B W

    1985-01-01

    A volunteer woman subject incurred injury to her right knee consisting of a torn anterior cruciate ligament and stretched medial collateral ligament during a lateral (+Gy) impact test. Similar injury has not been reported in the English-language literature an accidental sideward automotive crashes or lateral impact experimentation involving humans. The primary mechanism which produced this injury was external tibial rotation on the femur with the knee flexed. The factors contributing to the injury included extraordinarily forceful leg bracing by the subject, her knee joint laxity or hypermobility, and the absence of side supports to limit lower extremity flailing during the impact response. In future lateral impact tests, women subjects should be used with caution and any subject with abnormal joint mobility should be excluded from participation.

  15. Acute arterial occlusion after total knee arthroplasty.

    PubMed

    Gregory, Patricia C; Rogic, Roselyn; Eddington, Carolyn

    2006-11-01

    There are a number of complications associated with total knee-joint arthroplasty. These include deep venous thromboses, peroneal palsy, infection, anemia, and Ogilvie's syndrome. An uncommon but potentially limb-threatening complication is acute arterial occlusion. Approximately 35 cases have been reported in the orthopedic literature. Prompt recognition and treatment intervention are the keys to successful outcome. We describe the case of one patient who had mild peroneal palsy and developed acute arterial occlusion 9 days postoperatively while on the inpatient rehabilitation service. Prompt aggressive management restored arterial circulation to the lower limb. Careful management of patients after total knee arthroplasty requires an understanding that arterial occlusion is a rare limb-threatening complication of surgery, but that it is treatable with prompt, deliberate management. Physiatrists should be aware that this condition exists in postoperative knee-joint arthroplasty patients. They should pay careful attention to any patient with a history of peripheral vascular disease or postoperative peroneal palsy.

  16. Moxibustion Treatment for Knee Osteoarthritis

    PubMed Central

    Li, Ang; Wei, Zhi-Jian; Liu, Yi; Li, Bo; Guo, Xing; Feng, Shi-Qing

    2016-01-01

    Abstract To determine whether the administration of moxibustion is an effective treatment for knee osteoarthritis (KOA). We conducted a search of relevant articles using Medline, EMBASE, the Web of Science, and the Cochrane Library published before October 2015. The Western Ontario and McMaster Universities’ Osteoarthritis Index (WOMAC scale) and the short form 36 questionnaire (SF-36 scale) were assessed. Evidence grading was evaluated according to the Grading of Recommendations, Assessment, Development and Evaluation system. Four studies containing 746 participants fulfilled the inclusion criteria in the final analysis. In terms of quality of life (QOL), the meta-analysis of 2 randomized clinical trials (RCTs) showed significantly effects of moxibustion only in bodily pain (BP) compared with those in the control group (n = 348; weighted mean difference [WMD], 4.36; 95% confidence intervals [CIs], 2.27–6.44; P < 0.0001; heterogeneity: χ2 = 1.53, P = 0.22, I2 = 34%) in all of the subcategories of the SF-36 scale, with moderate quality. The meta-analysis of the 2 included trials showed that there was not a statistically significant difference in the pain or function subscale for the WOMAC scale when the 2 groups were compared (n = 322; WMD, 17.63; 95% CI, −23.15–58.41; P = 0.40; heterogeneity: χ2 = 19.42, P < 0.0001, I2 = 95%), with low or moderate quality separately. The administration of moxibustion can to some extent alleviate the symptoms of KOA. More rigorous, randomized controlled trials are required in the future. PMID:27057863

  17. A Novel Method of Evaluating Knee Joint Stability of Patients with Knee Osteoarthritis: Multiscale Entropy Analysis with A Knee-Aiming Task.

    PubMed

    Zhou, Diange; Zhang, Shijie; Zhang, Hui; Jiang, Long; Zhang, Jue; Fang, Jing

    2017-03-23

    Deteriorating knee stability is a local risk factor that reflects the occurrence and aggregative of osteoarthritis (OA). Despite the many biomechanics-based methods for assessing the structural stability of knee joints in clinics, these methods have many limitations. The stability of the knee joint relies on not only biomechanical factors, but also proprioception and the central nervous system. In this study, we attempt to depict the stability of knee joint from a holistic viewpoint, and a novel index of knee joint stability (IKJS) was thus extracted. We compared the differences of IKJS in 57 healthy volunteers and 55 patients with OA before and after total knee replacement (TKR). Analysis of Variance results demonstrated that there existed significant differences in IKJS among the three participating groups (<0.0001). Also, the IKJS of the operated leg in patients with knee OA increased remarkably after TKR (p < 0.0001). Furthermore, the results of the experiment suggested that the IKJS has sufficient reproducibility (ICC = 0.80). In conclusion, the proposed IKJS that employs the knee-aiming task is feasible for quantitatively determining knee stability. It can provide a potentially valuable and convenient tool to evaluate the effect of postoperative rehabilitation for patients with knee OA.

  18. High Knee Valgus in Female Subjects Does Not Yield Higher Knee Translations During Drop Landings: A Biplane Fluoroscopic Study

    PubMed Central

    Torry, Michael R.; Shelburne, Kevin B.; Myers, Casey; Giphart, J. Erik; Pennington, W. Wesley; Krong, Jacob P.; Peterson, Daniel S.; Steadman, J. Richard; Woo, Savio L-Y.

    2012-01-01

    The goal of this study was to determine the effects of peak knee valgus angle and peak knee abductor moment on the anterior, medial, and lateral tibial translations (ATT, MTT, LTT) in the ‘at risk’ female knee during drop landing. Fifteen female subjects performed drop landings from 40 cm. 3D knee motion was simultaneously recorded using a high speed, biplane fluoroscopy system and a video-based motion analysis system. Valgus knee angles and knee abduction moments were stratified into low, intermediate and high groups and peak ATT, MTT and LTT were compared between these groups with ANOVA (α = .05). Significant differences were observed between stratified groups in peak knee valgus angle (p < .0001) and peak knee abduction moment (p < .0001). However, no corresponding differences in peak ATT, LTT and MTT between groups exhibiting low to high peak knee valgus angles (ATT: p = .80; LTT: p = .25; MTT: p = .72); or, in peak ATT (p = .61), LTT (p = .26) and MTT (p = .96) translations when stratified according to low to high knee abduction moments, were found. We conclude that the healthy female knee is tightly regulated with regard to translations even when motion analysis derived knee valgus angles and abduction moments are high. PMID:22968826

  19. High knee valgus in female subjects does not yield higher knee translations during drop landings: a biplane fluoroscopic study.

    PubMed

    Torry, Michael R; Shelburne, Kevin B; Myers, Casey; Giphart, J Erik; Pennington, W Wesley; Krong, Jacob P; Peterson, Daniel S; Steadman, J Richard; Woo, Savio L-Y

    2013-02-01

    The goal of this study was to determine the effects of peak knee valgus angle and peak knee abductor moment on the anterior, medial, and lateral tibial translations (ATT, MTT, LTT) in the "at risk" female knee during drop landing. Fifteen female subjects performed drop landings from 40 cm. Three-dimension knee motion was simultaneously recorded using a high speed, biplane fluoroscopy system, and a video-based motion analysis system. Valgus knee angles and knee abduction moments were stratified into low, intermediate, and high groups and peak ATT, MTT, and LTT were compared between these groups with ANOVA (α = 0.05). Significant differences were observed between stratified groups in peak knee valgus angle (p < 0.0001) and peak knee abduction moment (p < 0.0001). However, no corresponding differences in peak ATT, LTT, and MTT between groups exhibiting low to high-peak knee valgus angles (ATT: p = 0.80; LTT: p = 0.25; MTT: p = 0.72); or, in peak ATT (p = 0.61), LTT (p = 0.26) and MTT (p = 0.96) translations when stratified according to low to high knee abduction moments, were found. We conclude that the healthy female knee is tightly regulated with regard to translations even when motion analysis derived knee valgus angles and abduction moments are high.

  20. Predictors of self-reported knee instability among patients with knee osteoarthritis: results of the Amsterdam osteoarthritis cohort.

    PubMed

    van der Esch, Martin; van der Leeden, Marike; Roorda, Leo D; Lems, Willem F; Dekker, Joost

    2016-12-01

    The aims of the study were to (i) determine the prevalence and course of self-reported knee instability at 2-year follow-up and (ii) identify factors predictive of retention of self-reported knee instability among patients with established knee osteoarthritis (OA). Among 201 patients from the Amsterdam Osteoarthritis (AMS-OA) cohort, demographic characteristics, self-reported knee instability, muscle strength, proprioception, pain, and physical function were assessed at baseline and at 2 years. Exercise over the past 2 years was assessed by evaluating the medical files. The course of self-reported knee instability was determined in patients reporting instability at baseline. Baseline predictors of self-reported knee instability were determined by uni- and multivariable logistic regression analyses. At baseline, 123 (61 %) patients reported knee instability, and of these, 85 (64 %) patients reported instability 2 years later, while 38 (29 %) reported no instability 2 years later. Poor proprioception and high pain assessed at baseline predicted retention of self-reported knee instability at 2 years among patients with self-reported instability at baseline. Knee instability is highly prevalent among patients with knee osteoarthritis. In patients with self-reported knee instability, the majority retained instability over 2 years. Poor proprioception and high pain predicted retention of self-reported knee instability over time.

  1. PERIPROSTHETIC FRACTURES IN TOTAL KNEE ARTHROPLASTY

    PubMed Central

    de Alencar, Paulo Gilberto Cimbalista; De Bortoli, Giovani; Ventura Vieira, Inácio Facó; Uliana, Christiano Saliba

    2015-01-01

    The increasing number of total knee arthroplasties, in combination with the population's longer life expectancy, has led to a greater number of long-term complications. These add to the poor bone quality of elderly patients and often culminate in periprosthetic fractures. This complex orthopedic problem has a great diversity of clinical presentation. It may affect any of the bones in the knee and, because of the difficulty in finding solutions, may lead to disastrous outcomes. Its treatment requires that orthopedists should have broad knowledge both of arthroplasty techniques and of osteosynthesis, as well as an elaborate therapeutic arsenal including, for example, access to a bone bank. PMID:27022546

  2. Total knee arthroplasty in vascular malformation

    PubMed Central

    Bhende, Harish; Laud, Nanadkishore; Deore, Sandeep; Shashidhar, V

    2015-01-01

    In Klippel–Trenaunay syndrome, vascular malformations are not only in skin and superficial soft tissues but also in deep tissues like muscles bones and joints. It is well documemted that these recurrent intraarticular bleeds can cause early arthritis and joint pain. Performing arthroplasty in such patients is difficult and fraught with complications. We describe such a case where navigated total knee arthroplasty was performed with success to avoid the problems of intra medullary alignment used in the presence of intra medullary vascular malformations. We also suggest certain measures when knee arthroplasty is considered in such patients. PMID:26538765

  3. Anterolateral rotatory instability of the knee.

    PubMed

    Guenther, Daniel; Griffith, Chad; Lesniak, Bryson; Lopomo, Nicola; Grassi, Alberto; Zaffagnini, Stefano; Fu, Freddie H; Musahl, Volker

    2015-10-01

    Recent publications have generated renewed interest in the anatomy of the anterolateral capsule. Knowledge of the biomechanical function of the anterolateral components is lacking. Further research is required to evaluate the influence of the anterolateral capsule on rotatory laxity of the knee. The role of surgical procedures, such as an extra-articular tenodesis or lateral plasty, has to be defined based on quantification of the injury. This article seeks to summarize the current literature and discusses the role of the anterolateral capsule and reconstructive techniques in combined ligamentous knee trauma. Level of evidence V.

  4. Snapping Pes Syndrome after Unicompartmental Knee Arthroplasty

    PubMed Central

    Taketomi, Shuji; Yamagami, Ryota; Tahara, Keitaro; Tanaka, Sakae

    2016-01-01

    Snapping pes syndrome is defined as a snapping sensation in the medial knee caused by pes anserinus and rarely occurs. Snapping pes syndrome after unicompartmental knee arthroplasty (UKA) has not been reported yet. We experienced two cases with this syndrome after UKA. Conservative treatment was effective in one case, while surgical excision of the gracilis tendon was necessary to relieve painful snapping in the other case. The main cause of the first case might be posteromedial overhang of the tibial tray that reached up to 5 mm. The probable cause of the second case was posteromedial overhang of the mobile bearing. PMID:27274476

  5. Spitalfields knees study--a photographic challenge.

    PubMed

    Finan, Nicola; Oliver, Matthew; Shepperd, John

    2007-06-01

    This paper reports a study into human lower limb anatomy based on the Spitalfields collection of human skeletons at the Natural History Museum, London. The objective was to document knee alignment in a range of rotations, and also to define the topography of the knee surfaces. The work was a collaborative between the Medical Illustration department and the orthopaedic surgical team. This project involved photographic challenges that required development of versatile techniques in order to generate credible scientific data. The results have produced a valuable and unique record not previously available. It demonstrates the key role medical photography offers in this type of investigation.

  6. The infected total knee: management options.

    PubMed

    Cuckler, John M

    2005-06-01

    The management of infection after total knee arthroplasty depends on the chronicity of the infection, host factors, and sensitivity of the infecting bacteria. Two-stage salvage consisting of removal of implants and cement, placement of an antibiotic spacer, and appropriate intravenous antibiotic therapy followed by reimplantation with an antibiotic-impregnated cement appears to be the predominant approach to managing this complication. The use of articulated spacers consisting of the sterilized femoral and polyethylene components with antibiotic cement allows maintenance of motion and bone stock. This report details the author's experience with 44 infected knee arthroplasties.

  7. Long-term clinical outcomes and survivorship after total knee arthroplasty using a rotating platform knee prosthesis: a meta-analysis.

    PubMed

    Hopley, Colin D J; Crossett, Lawrence S; Chen, Antonia F

    2013-01-01

    A systematic search identified 29 papers reporting survivorship and clinical and function Knee Society Scores (KSS) of 6437 total knee replacements using the Low Contact Stress (LCS) Rotating Platform (RP) mobile bearing knee. Low Contact Stress RP survivorship and KSS outcomes were compared with non-LCS knees in the Swedish knee registry at comparable time periods and in 2 independent systematic reviews of knee arthroplasty outcomes. There is a substantial body of mainly observational evidence supporting the LCS RP knee. Knee Society Score outcomes were comparable for LCS RP and non-LCS RP knees at up to 15 years of follow-up, with mean clinical and function scores ranging from 72 to 96 and 58 to 90, respectively. Survivorship of LCS RP knees up to 14 years was higher than that for all knees in the Swedish Knee Registry.

  8. Complicated Congenital Dislocation of the Knee: A Case Report

    PubMed Central

    Madadi, Firooz; Tahririan, Mohammad A.; Karami, Mohsen; Madadi, Firoozeh

    2016-01-01

    Congenital dislocation of the knee (CDK) is a rare disorder. We report the case of a 7-year-old girl with bilateral knee stiffness, marked anterior bowing of both legs, and inability to walk without aid. Radiologic investigation revealed bilateral knee joint dislocation accompanied by severe anterior bowing of both tibia proximally and posterior bowing of both femur distally, demonstrating a complicated congenital knee dislocation. Two-staged open reduction with proximal tibial osteotomy was performed to align the reduced knee joints. The patient was completely independent in her daily activities after surgical correction. PMID:27847857

  9. Unexpected wear of an unicompartimental knee arthroplasty in oxidized zirconium.

    PubMed

    Luyet, Anais; Fischer, Jean-François; Jolles, Brigitte M; Lunebourg, Alexandre

    2015-12-01

    Unicompartimental knee arthroplasty is a successful procedure for the treatment of localized osteoarthritis to one compartment of the knee with good long-term results. However, several modes of failure of unicompartimental knee arthroplasty have been described, namely aseptic or septic loosening, progression of disease, wear, and instability. Metallosis after unicompartimental knee arthroplasty is rarely reported and is most often related with polyethylene wear or break. We report on a case of rapid failure of unicompartimental knee arthroplasty in oxidized zirconium associated with metallosis secondary to the dislocation of the polyethylene.

  10. Segmentation of multiple knee bones from CT for orthopedic knee surgery planning.

    PubMed

    Wu, Dijia; Sofka, Michal; Birkbeck, Neil; Zhou, S Kevin

    2014-01-01

    Patient-specific orthopedic knee surgery planning requires precisely segmenting from 3D CT images multiple knee bones, namely femur, tibia, fibula, and patella, around the knee joint with severe pathologies. In this work, we propose a fully automated, highly precise, and computationally efficient segmentation approach for multiple bones. First, each bone is initially segmented using a model-based marginal space learning framework for pose estimation followed by non-rigid boundary deformation. To recover shape details, we then refine the bone segmentation using graph cut that incorporates the shape priors derived from the initial segmentation. Finally we remove overlap between neighboring bones using multi-layer graph partition. In experiments, we achieve simultaneous segmentation of femur, tibia, patella, and fibula with an overall accuracy of less than 1mm surface-to-surface error in less than 90s on hundreds of 3D CT scans with pathological knee joints.

  11. Blastomycosis infection of the knee treated with staged total knee arthroplasty.

    PubMed

    MacLean, Ian S; Day, Shandra R; Moore, Christopher C; Browne, James A

    2015-12-01

    Blastomycosis is a rare fungal disease that can cause intraarticular infection and joint destruction requiring surgical reconstruction. We describe a patient who presented with destruction of the knee joint of unknown etiology. The patient was initially treated with debridement and spacer placement followed by antifungal therapy after cultures grew blastomycosis. Following adequate treatment of the infection, the patient was taken back to the operating room for reconstruction with a total knee arthroplasty. The patient had a successful outcome with no evidence of infection at two years following surgery. To our knowledge, this case report represents the first documented case in which a blastomycotic infection of a native knee was successfully treated with a two-stage total knee arthroplasty.

  12. Accuracy of knee range of motion assessment after total knee arthroplasty.

    PubMed

    Lavernia, Carlos; D'Apuzzo, Michele; Rossi, Mark D; Lee, David

    2008-09-01

    Measurement of knee joint range of motion (ROM) is important to assess after total knee arthroplasty. Our objective was to determine level of agreement and accuracy between observers with different knowledge on total ROM after total knee arthroplasty. Forty-one patients underwent x-ray of active and passive knee ROM (gold standard). Five different raters evaluated observed and measured ROM: orthopedic surgeon, clinical fellow, physician assistant, research fellow, and a physical therapist. A 1-way analysis of variance was used to determine differences in ROM between raters over both conditions. Limit of agreement for each rater for both active and passive total ROM under both conditions was calculated. Analysis of variance indicated a difference between raters for all conditions (range, P = .004 to P < or =.0001). The trend for all raters was to overestimate ROM at higher ranges. Assessment of ROM through direct observation without a goniometer provides inaccurate findings.

  13. Soft tissue artifact compensation in knee kinematics by multi-body optimization: Performance of subject-specific knee joint models.

    PubMed

    Clément, Julien; Dumas, Raphaël; Hagemeister, Nicola; de Guise, Jaques A

    2015-11-05

    Soft tissue artifact (STA) distort marker-based knee kinematics measures and make them difficult to use in clinical practice. None of the current methods designed to compensate for STA is suitable, but multi-body optimization (MBO) has demonstrated encouraging results and can be improved. The goal of this study was to develop and validate the performance of knee joint models, with anatomical and subject-specific kinematic constraints, used in MBO to reduce STA errors. Twenty subjects were recruited: 10 healthy and 10 osteoarthritis (OA) subjects. Subject-specific knee joint models were evaluated by comparing dynamic knee kinematics recorded by a motion capture system (KneeKG™) and optimized with MBO to quasi-static knee kinematics measured by a low-dose, upright, biplanar radiographic imaging system (EOS(®)). Errors due to STA ranged from 1.6° to 22.4° for knee rotations and from 0.8 mm to 14.9 mm for knee displacements in healthy and OA subjects. Subject-specific knee joint models were most effective in compensating for STA in terms of abduction-adduction, inter-external rotation and antero-posterior displacement. Root mean square errors with subject-specific knee joint models ranged from 2.2±1.2° to 6.0±3.9° for knee rotations and from 2.4±1.1 mm to 4.3±2.4 mm for knee displacements in healthy and OA subjects, respectively. Our study shows that MBO can be improved with subject-specific knee joint models, and that the quality of the motion capture calibration is critical. Future investigations should focus on more refined knee joint models to reproduce specific OA knee geometry and physiology.

  14. The SIGN nail for knee fusion: technique and clinical results

    PubMed Central

    Anderson, Duane Ray; Anderson, Lucas Aaron; Haller, Justin M.; Feyissa, Abebe Chala

    2016-01-01

    Purpose: Evaluate the efficacy of using the SIGN nail for instrumented knee fusion. Methods: Six consecutive patients (seven knees, three males) with an average age of 30.5 years (range, 18–50 years) underwent a knee arthrodesis with SIGN nail (mean follow-up 10.7 months; range, 8–14 months). Diagnoses included tuberculosis (two knees), congenital knee dislocation in two knees (one patient), bacterial septic arthritis (one knee), malunited spontaneous fusion (one knee), and severe gout with 90° flexion contracture (one knee). The nail was inserted through an anteromedial entry point on the femur and full weightbearing was permitted immediately. Results: All knees had clinical and radiographic evidence of fusion at final follow-up and none required further surgery. Four of six patients ambulated without assistive device, and all patients reported improved overall physical function. There were no post-operative complications. Conclusion: The technique described utilizing the SIGN nail is both safe and effective for knee arthrodesis and useful for austere environments with limited fluoroscopy and implant options. PMID:27163095

  15. Total knee arthroplasty in patients with prior ipsilateral hip fusion.

    PubMed

    Romness, D W; Morrey, B F

    1992-03-01

    Sixteen total knee arthroplasties performed between 1977 and 1985 in 13 patients with prior ipsilateral hip arthrodesis or ankylosis were studied to determine the preferred sequence and long-term follow-up of procedures in this clinical setting. Twelve of 16 underwent fusion takedown and total hip arthroplasty prior to knee replacement. The average age at total knee arthroplasty was 52.7 years and the average time from hip fusion to total knee arthroplasty was 36.3 years. Mean follow-up after total knee arthroplasty was 5.5 years (range, 2.3 to 10 years). The Hospital for Special Surgery knee score increased from a mean of 31.8 preoperatively to 72.2 after surgery. In patients who had conversion of the hip fusion prior to knee replacement, knee scores were 28 before and 72.5 after both procedures. Patients who retained their hip fusion had mean scores of 43.5 and 72.1, respectively. None of the knees has been removed and 14 of 16 had no pain at last follow-up. One had mild pain and one had moderate pain attributed to pes anserine bursitis. Although the numbers are small, this experience reveals that takedown of the fusion with total hip arthroplasty is an effective technique before performing the knee replacement. Though successful in some instances, the experience is too small to show that if hip fusion is in good position, knee replacement without fusion takedown is acceptable.

  16. Recent Advances and Developments in Knee Surgery: Principles of Periprosthetic Knee Fracture Management

    PubMed Central

    Chimutengwende-Gordon, Mukai; Khan, Wasim; Johnstone, David

    2012-01-01

    The management of distal femoral, tibial and patellar fractures after total knee arthroplasty can be complex. The incidence of these fractures is increasing as the number of total knee arthroplasties being performed and patient longevity is increasing. There is a wide range of treatment options including revision arthroplasty for loose implants. This review article discusses the epidemiology, risk factors, classification and treatment of these fractures. PMID:22888380

  17. Robotic Total Knee Arthroplasty: Surgical Assistant for a Customized Normal Kinematic Knee.

    PubMed

    Urish, Kenneth L; Conditt, Michael; Roche, Martin; Rubash, Harry E

    2016-09-01

    Although current total knee arthroplasty (TKA) is considered a highly successful surgical procedure, patients undergoing TKA can still experience substantial functional impairment and increased revision rates as compared with those undergoing total hip arthroplasty. Robotic-assisted surgery has been available clinically for almost 15 years and was developed, in part, to address these concerns. Robotic-assisted surgery aims to improve TKA by enhancing the surgeon's ability to optimize soft tissue balancing, reproduce alignment, and restore normal knee kinematics. Current systems include a robotic arm with a variety of different navigation systems with active, semi-active, or passive control. Semi-active systems have become the dominant strategy, providing a haptic window through which the surgeon consistently prepares a TKA based on preoperative planning. A review of previous designs and clinical studies demonstrates that these robotic systems decrease variability and increase precision, primarily with the mechanical axis and restoration of the joint line. Future design objectives include precise planning and consistent intraoperative execution. Preoperative planning, intraoperative sensors, augmenting surgical instrumentation, and biomimetic surfaces will be used to re-create the 4-bar linkage system in the knee. Implants will be placed so that the knee functions with a medial pivot, lateral rollback, screw home mechanism, and patellar femoral tracking. Soft tissue balancing will become more than equalizing the flexion and extension gaps and will match the kinematics to a normal knee. Together, coupled with advanced knee designs, they may be the key to a patient stating, "My knee feels like my natural knee." [Orthopedics. 2016; 39(5):e822-e827.].

  18. Reverse Engineering Nature to Design Biomimetic Total Knee Implants.

    PubMed

    Varadarajan, Kartik Mangudi; Zumbrunn, Thomas; Rubash, Harry E; Malchau, Henrik; Muratoglu, Orhun K; Li, Guoan

    2015-10-01

    While contemporary total knee arthroplasty (TKA) provides tremendous clinical benefits, the normal feel and function of the knee is not fully restored. To address this, a novel design process was developed to reverse engineer "biomimetic" articular surfaces that are compatible with normal soft-tissue envelope and kinematics of the knee. The biomimetic articular surface is created by moving the TKA femoral component along in vivo kinematics of normal knees and carving out the tibial articular surface from a rectangular tibial block. Here, we describe the biomimetic design process. In addition, we utilize geometric comparisons and kinematic simulations to show that; (1) tibial articular surfaces of conventional implants are fundamentally incompatible with normal knee motion, and (2) the anatomic geometry of the biomimetic surface contributes directly to restoration of normal knee kinematics. Such biomimetic implants may enable us to achieve the long sought after goal of a "normal" knee post-TKA surgery.

  19. Kinematics and Mechanical Properties of Knees following Patellar Replacing and Patellar Retaining Total Knee Arthroplasty

    PubMed Central

    Huang, Rongying; Liu, Yanqiang; Zhu, Jun

    2015-01-01

    Knee injury is a common medical issue. A full understanding of the kinematics and mechanical properties of knees following total knee arthroplasty (TKA) repair utilizing patellar replacement (only the base of the patella is replaced) versus patellar retaining surgical techniques is still lacking. In the current paper, we investigated magnetic resonance (MR) imaging data from knees repaired by these two methods and evaluated total knee models created using imaging reconstruction technology that simulated gait conditions. Results revealed that patellar replacement had little influence on tibiofemoral kinematics, although the tibia-surface equivalent stress increased slightly. By contrast, patellar replacement had a significant influence on the patellofemoral joint; patellar internal rotation, external rotation, and medial-lateral translation were all increased. Moreover, the stress distribution on patellar prostheses was altered, resulting in an increased surface maximal equivalent stress on the corresponding area. Moreover, during the gait cycle, we found that the area with maximal equivalent stress shifted its position. Finally, the patellofemoral joint showed decreased motion stability. From the view of kinematics and mechanics, this paper suggests that patella should be retained during TKA if it is possible. The present study presented approaches and technologies for evaluating kinematics and mechanical properties of total knee joint after TKA under gait loads. PMID:27057134

  20. Predicting dynamic knee joint load with clinical measures in people with medial knee osteoarthritis.

    PubMed

    Hunt, Michael A; Bennell, Kim L

    2011-08-01

    Knee joint loading, as measured by the knee adduction moment (KAM), has been implicated in the pathogenesis of knee osteoarthritis (OA). Given that the KAM can only currently be accurately measured in the laboratory setting with sophisticated and expensive equipment, its utility in the clinical setting is limited. This study aimed to determine the ability of a combination of four clinical measures to predict KAM values. Three-dimensional motion analysis was used to calculate the peak KAM at a self-selected walking speed in 47 consecutive individuals with medial compartment knee OA and varus malalignment. Clinical predictors included: body mass; tibial angle measured using an inclinometer; walking speed; and visually observed trunk lean toward the affected limb during the stance phase of walking. Multiple linear regression was performed to predict KAM magnitudes using the four clinical measures. A regression model including body mass (41% explained variance), tibial angle (17% explained variance), and walking speed (9% explained variance) explained a total of 67% of variance in the peak KAM. Our study demonstrates that a set of measures easily obtained in the clinical setting (body mass, tibial alignment, and walking speed) can help predict the KAM in people with medial knee OA. Identifying those patients who are more likely to experience high medial knee loads could assist clinicians in deciding whether load-modifying interventions may be appropriate for patients, whilst repeated assessment of joint load could provide a mechanism to monitor disease progression or success of treatment.

  1. Knee Joint Loads and Surrounding Muscle Forces during Stair Ascent in Patients with Total Knee Replacement

    PubMed Central

    Rasnick, Robert; Standifird, Tyler; Reinbolt, Jeffrey A.; Cates, Harold E.

    2016-01-01

    Total knee replacement (TKR) is commonly used to correct end-stage knee osteoarthritis. Unfortunately, difficulty with stair climbing often persists and prolongs the challenges of TKR patents. Complete understanding of loading at the knee is of great interest in order to aid patient populations, implant manufacturers, rehabilitation, and future healthcare research. Musculoskeletal modeling and simulation approximates joint loading and corresponding muscle forces during a movement. The purpose of this study was to determine if knee joint loadings following TKR are recovered to the level of healthy individuals, and determine the differences in muscle forces causing those loadings. Data from five healthy and five TKR patients were selected for musculoskeletal simulation. Variables of interest included knee joint reaction forces (JRF) and the corresponding muscle forces. A paired samples t-test was used to detect differences between groups for each variable of interest (p<0.05). No differences were observed for peak joint compressive forces between groups. Some muscle force compensatory strategies appear to be present in both the loading and push-off phases. Evidence from knee extension moment and muscle forces during the loading response phase indicates the presence of deficits in TKR in quadriceps muscle force production during stair ascent. This result combined with greater flexor muscle forces resulted in similar compressive JRF during loading response between groups. PMID:27258086

  2. Cysts about the knee: evaluation and management.

    PubMed

    Stein, Drew; Cantlon, Matthew; Mackay, Brendan; Hoelscher, Christian

    2013-08-01

    Popliteal (Baker) cysts, meniscal cysts, proximal tibiofibular joint cysts, and cruciate ligament ganglion cysts are cystic masses commonly found about the knee. Popliteal cysts form when a bursa swells with synovial fluid, with or without a clear inciting etiology. Presentation ranges from asymptomatic to painful, limited knee motion. Management varies based on symptomatology and etiology. Meniscal cysts form within or adjacent to the menisci. These collections of synovial fluid are thought to develop from translocation of synovial cells or extravasation of synovial fluid into the meniscus through a tear. Joint-line pain and swelling are common symptoms. Management entails partial meniscectomy with cyst decompression or excision. Proximal tibiofibular joint cysts are rare, and their etiology remains unclear. Pain and swelling secondary to local tissue invasion is common, and management consists of surgical excision. Cruciate ligament ganglion cysts have no clear etiology but are associated with mucoid degeneration of the anterior and posterior cruciate ligaments, knee trauma, and synovial translocation into these ligaments. Knee pain and limited range of motion, especially with exercise, are common presenting symptoms. In symptomatic cases, arthroscopic excision is commonly performed.

  3. [Chronic sports injuries of the knee joint].

    PubMed

    Mannil, M; Andreisek, G; Weishaupt, D; Fischer, M A

    2016-05-01

    Chronic sports injuries of the knee joint are common and mainly caused by repetitive (micro) trauma and exertion. Chronic insertion tendinopathies and avulsion fractures and symptoms related to entrapment, friction and impingement can be pathophysiologically distinguished in athletes. In this review, we depict the characteristic magnetic resonance imaging (MRI) findings of the most commonly occurring pathologies.

  4. Extensor tendon ruptures after total knee arthroplasty.

    PubMed

    Bonnin, M; Lustig, S; Huten, D

    2016-02-01

    Extensor tendon rupture is a rare but serious complication after total knee arthroplasty (TKA) that impairs active knee extension, thereby severely affecting knee function. Surgery is usually required. Surgical options range from simple suturing to allograft reconstruction of the entire extensor mechanism and include intermediate methods such as reconstruction using neighbouring tendons or muscles, synthetic ligament implantation, and partial allograft repair. Simple suturing carries a high failure rate and should therefore be routinely combined with tissue augmentation using a neighbouring tendon or a synthetic ligament. After allograft reconstruction, outcomes are variable and long-term complications common. Salvage procedures for managing the most severe cases after allograft failure involve reconstruction using gastrocnemius or vastus flaps. Regardless of the technique used, suturing must be performed under tension, with the knee fully extended, and rehabilitation must be conducted with great caution. Weaknesses of available case-series studies include small sample sizes, heterogeneity, and inadequate follow-up duration. All treatment options are associated with substantial failure rates. The patient should be informed of this fact and plans made for a salvage option. Here, the main techniques and their outcomes are discussed, and a therapeutic strategy is suggested.

  5. Tibial osteotomy for the varus osteoarthritic knee.

    PubMed

    Aglietti, P; Rinonapoli, E; Stringa, G; Taviani, A

    1983-06-01

    High tibial osteotomy is a reliable method for relieving pain in the varus osteoarthritic knee. In a review of 139 osteotomies, excellent and good results were noted in 64% of the knees after a follow-up period of at least ten years. The ideal candidate for this operation has Grade I or II osteoarthritis; less than 10 degrees of varus deformity, as measured by a single leg standing roentgenogram; no lateral subluxation; and no instability. The lateral closed wedge osteotomy without internal fixation is the preferred technique, and correction beyond the normal anatomic position, to 5 degrees of valgus, is advised. Protected weight-bearing after the second postoperative day is allowed. Complications have been infrequent and minor. Forty-seven knees were managed in this manner, and 88% had an excellent or good result at a four-year follow-up evaluation. In the majority of the well corrected knees, the alignment did not change with time, and the osteoarthritis did not progress. No failures in this series were attributable to the associated patellofemoral osteoarthritis; the reaction of the patellofemoral joint to osteotomy is obscure.

  6. [Unicondylar replacement of the knee joint.].

    PubMed

    Stedrý, V; Vanecek, L

    1999-01-01

    Twenty-nine unicondylar replacements of the knee joint (UKR) of St. Georg type were implanted in 27 patients at the Orthopaedic Clinic IPVZ in the period between 1985-1994. The average age in case of females was 73 years, in case of men 71 years. The most frequent indication was osteoarthritis of the knee joint of varus type. Two patients (7 %) had to be reoperated on for aseptic loosening of the tibial component, on average 5,5 years after the surgery. Revision surgery for breaking of femoral component was performed in five cases, on average 6 years after the primary implantation. The authores evaluated 16 patients with UKR still in situ. In 8 patients the prosthesis is entirely painless, in 10 joints operated on the radiograph showed a developed femoropatelar osteoarthritis, osteoarthritic changes of the opposite compartment in 2 of them and a radioluscent line up to 1 mm in 3 cases. Despite a high frequency of late complications the authors consider UKR for an alternative to high supratubercular osteotomy of tibia in older patients, for a suitable method of the treatment of osteochondritis dissecans and Ahlbäck disease of the knee joint. The success of this operation is conditioned by a perfect surgical technique and implant of suitable design. Key words: replacement of the knee joint, aseptic loosening, fatique failure of material.

  7. Knee joint functional range of movement prior to and following total knee arthroplasty measured using flexible electrogoniometry.

    PubMed

    Myles, Christine M; Rowe, Philip J; Walker, Colin R C; Nutton, Richard W

    2002-08-01

    The functional ranges of movement of the knee were investigated in a group of patients with knee osteoarthritis (n = 42, mean age 70 years) before, 4 months and at 18-24 months after total knee arthroplasty and then compared with age matched normal subjects (n = 20, mean age 67 years). Flexible electrogoniometry was used to record the maximum flexion-extension angle, the minimum flexion-extension angle and flexion-extension excursions of both knees during eleven functional activities along with the active and passive knee joint range of motion measured using a manual goniometer. Over the eleven functional activities the patients pre-operatively exhibited 28% less knee joint excursion than normal age matched subjects. By 18-24 months following total knee arthroplasty only 2% of this deficit was recovered. Statistically this recovery was only significant in level walking, slope ascent and slope descent. A greater range of movement was measured in a non-weight bearing position than was used in weight bearing functional activity. It is concluded that total knee arthroplasty gives rise to little improvement in knee motion during functional activities and that functional range of movement of the knee remains limited when compared to normal knee function for a minimum of 18 months following operation.

  8. Effects of proprioceptive circuit exercise on knee joint pain and muscle function in patients with knee osteoarthritis.

    PubMed

    Ju, Sung-Bum; Park, Gi Duck; Kim, Sang-Soo

    2015-08-01

    [Purpose] This study applied proprioceptive circuit exercise to patients with degenerative knee osteoarthritis and examined its effects on knee joint muscle function and the level of pain. [Subjects] In this study, 14 patients with knee osteoarthritis in two groups, a proprioceptive circuit exercise group (n = 7) and control group (n = 7), were examined. [Methods] IsoMed 2000 (D&R Ferstl GmbH, Hemau, Germany) was used to assess knee joint muscle function, and a Visual Analog Scale was used to measure pain level. [Results] In the proprioceptive circuit exercise group, knee joint muscle function and pain levels improved significantly, whereas in the control group, no significant improvement was observed. [Conclusion] A proprioceptive circuit exercise may be an effective way to strengthen knee joint muscle function and reduce pain in patients with knee osteoarthritis.

  9. Data Collection and Analysis Using Wearable Sensors for Monitoring Knee Range of Motion after Total Knee Arthroplasty

    PubMed Central

    Chiang, Chih-Yen; Chen, Kun-Hui; Liu, Kai-Chun; Hsu, Steen Jun-Ping; Chan, Chia-Tai

    2017-01-01

    Total knee arthroplasty (TKA) is the most common treatment for degenerative osteoarthritis of that articulation. However, either in rehabilitation clinics or in hospital wards, the knee range of motion (ROM) can currently only be assessed using a goniometer. In order to provide continuous and objective measurements of knee ROM, we propose the use of wearable inertial sensors to record the knee ROM during the recovery progress. Digitalized and objective data can assist the surgeons to control the recovery status and flexibly adjust rehabilitation programs during the early acute inpatient stage. The more knee flexion ROM regained during the early inpatient period, the better the long-term knee recovery will be and the sooner early discharge can be achieved. The results of this work show that the proposed wearable sensor approach can provide an alternative for continuous monitoring and objective assessment of knee ROM recovery progress for TKA patients compared to the traditional goniometer measurements. PMID:28241434

  10. Does a standard outpatient physiotherapy regime improve the range of knee motion after primary total knee arthroplasty?

    PubMed

    Mockford, Brian James; Thompson, Neville W; Humphreys, Patricia; Beverland, David E

    2008-12-01

    The aim of this study was to investigate whether a standard course of outpatient physiotherapy improves the range of knee motion after primary total knee arthroplasty. One hundred and fifty patients were randomly assigned into one of 2 groups. One group received outpatient physiotherapy for 6 weeks (group A). Another received no outpatient physiotherapy (group B). Range of knee motion was measured preoperatively and at 1-year review. Validated knee scores and an SF-12 health questionnaire were also recorded. Although patients in group A achieved a greater range of knee motion than those in group B, this was not statistically significant. No difference either was noted in any of the outcome measures used. In conclusion, outpatient physiotherapy does not improve the range of knee motion after primary total knee arthroplasty.

  11. Measured flexion following total knee arthroplasty.

    PubMed

    Mai, Kenny T; Verioti, Christopher A; Hardwick, Mary E; Ezzet, Kace A; Copp, Steven N; Colwell, Clifford W

    2012-10-01

    Postoperative flexion is an important factor in the outcome of total knee arthroplasty. Although normal activities of daily living require a minimum of 105° to 110° of flexion, patients from non-Western cultures often engage in activities such as kneeling and squatting that require higher flexion. The desire to achieve greater flexion serves as the driving force for prosthetic modifications, including high-flexion designs. Techniques used to measure knee flexion and knee position during measurement are not often described or are different depending on the examiner. The purpose of this study was to compare active (self) and passive (assisted) flexion after successful total knee arthroplasty for 5 prostheses (2 standard and 3 high-flexion) using clinical (goniometer) and radiographic (true lateral radiograph) measurement techniques by different independent examiners.At a mean follow-up of 2.7 years (range, 1-5.6 years), a total of 108 patients (144 total knee arthroplasties) had completed the study. Mean postoperative active flexion was 111° clinically and 109° radiographically for the standard designs and 114° clinically and 117° radiographically for the high-flexion designs. Adding passive flexion increased flexion to 115° clinically and 117° radiographically for the standard designs and 119° clinically and 124° radiographically for the high-flexion designs. Flexion differences between the 2 measurement techniques (active vs passive and clinically vs radiographically) were statistically significant (P<.05). These findings demonstrate the importance of describing how flexion is measured in studies and understanding how the method of measurement can affect the findings.

  12. Influence of Bicompartmental Knee Replacement on Stand-to-Sit Movement

    ERIC Educational Resources Information Center

    Wang, He; Frame, Jeff; Rolston, Lindsey

    2012-01-01

    Knee osteoarthritis often occurs in medial and patellofemoral compartments. A bicompartmental knee replacement system replaces these two affected knee compartments and keeps the lateral compartment and cruciate ligaments intact. It is yet to be determined whether limbs with bicompartmental knee systems can demonstrate frontal-plane knee mechanics…

  13. Decreased Knee Joint Loading Associated With Early Knee Osteoarthritis After Anterior Cruciate Ligament Injury

    PubMed Central

    Wellsandt, Elizabeth; Gardinier, Emily S.; Manal, Kurt; Axe, Michael J.; Buchanan, Thomas S.; Snyder-Mackler, Lynn

    2015-01-01

    Background Anterior cruciate ligament (ACL) injury predisposes individuals to early-onset knee joint osteoarthritis (OA). Abnormal joint loading is apparent after ACL injury and reconstruction. The relationship between altered joint biomechanics and the development of knee OA is unknown. Hypothesis Altered knee joint kinetics and medial compartment contact forces initially after injury and reconstruction are associated with radiographic knee OA 5 years after reconstruction. Study Design Case-control study; Level of evidence, 3. Methods Individuals with acute, unilateral ACL injury completed gait analysis before (baseline) and after (posttraining) preoperative rehabilitation and at 6 months, 1 year, and 2 years after reconstruction. Surface electromyographic and knee biomechanical data served as inputs to an electromyographically driven musculoskeletal model to estimate knee joint contact forces. Patients completed radiographic testing 5 years after reconstruction. Differences in knee joint kinetics and contact forces were compared between patients with and those without radiographic knee OA. Results Patients with OA walked with greater frontal plane interlimb differences than those without OA (nonOA) at baseline (peak knee adduction moment difference: 0.00 ± 0.08 N·m/kg·m [nonOA] vs −0.15 ± 0.09 N·m/kg·m [OA], P = .014; peak knee adduction moment impulse difference: −0.001 ± 0.032 N·m·s/kg·m [nonOA] vs −0.048 ± 0.031 N·m·s/kg·m [OA], P = .042). The involved limb knee adduction moment impulse of the group with osteoarthritis was also lower than that of the group without osteoarthritis at baseline (0.087 ± 0.023 N·m·s/kg·m [nonOA] vs 0.049 ± 0.018 N·m·s/kg·m [OA], P = .023). Significant group differences were absent at posttraining but reemerged 6 months after reconstruction (peak knee adduction moment difference: 0.02 ± 0.04 N·m/kg·m [nonOA] vs −0.06 ± 0.11 N·m/kg·m [OA], P = .043). In addition, the OA group walked with lower peak

  14. External Knee Adduction and Flexion Moments during Gait and Medial Tibiofemoral Disease Progression in Knee Osteoarthritis

    PubMed Central

    Chang, Alison H.; Moisio, Kirsten C.; Chmiel, Joan S.; Eckstein, Felix; Guermazi, Ali; Prasad, Pottumarthi V.; Zhang, Yunhui; Almagor, Orit; Belisle, Laura; Hayes, Karen; Sharma, Leena

    2015-01-01

    Objective Test the hypothesis that greater baseline peak external knee adduction moment (KAM), KAM impulse, and peak external knee flexion moment (KFM) during the stance phase of gait are associated with baseline-to-2-year medial tibiofemoral cartilage damage and bone marrow lesion progression, and cartilage thickness loss. Methods Participants all had knee OA in at least one knee. Baseline peak KAM, KAM impulse, and peak KFM (normalized to body weight and height) were captured and computed using a motion analysis system and 6 force plates. Participants underwent MRI of both knees at baseline and two years later. To assess the association between baseline moments and baseline-to-2-year semiquantitative cartilage damage and bone marrow lesion progression and quantitative cartilage thickness loss, we used logistic regression with generalized estimating equations (GEE), adjusting for gait speed, age, gender, disease severity, knee pain severity, and medication use. Results The sample consisted of 391 knees (204 persons): mean age 64.2 years (SD 10.0); BMI 28.4 kg/m2 (5.7); 156 (76.5%) women. Greater baseline peak KAM and KAM impulse were each associated with worsening of medial bone marrow lesions, but not cartilage damage. Higher baseline KAM impulse was associated with 2-year medial cartilage thickness loss assessed both as % loss and as a threshold of loss, whereas peak KAM was related only to % loss. There was no relationship between baseline peak KFM and any medial disease progression outcome measures. Conclusion Findings support targeting KAM parameters in an effort to delay medial OA disease progression. PMID:25677110

  15. Knee kinematics during walking at different speeds in people who have undergone total knee replacement.

    PubMed

    McClelland, Jodie A; Webster, Kate E; Feller, Julian A; Menz, Hylton B

    2011-06-01

    People who have undergone total knee replacement (TKR) experience difficulties in some daily activities including walking. Walking at faster speeds requires more knee flexion and may therefore present a greater challenge following TKR. The aim of this study was to compare the knee kinematics of patients following TKR and unimpaired controls during comfortable and fast walking speeds. Forty patients (22 women, 18 men) 12 months following TKR and 40 control participants (matched for age and sex) were assessed during walking at self-selected comfortable and fast speeds using three dimensional motion analysis. The group averages of spatiotemporal and peak kinematic characteristics in the sagittal, coronal and transverse movement planes were compared using univariate analysis of variance with walking speed as a co-variate. The TKR group walked with significantly reduced cadence (p < 0.001 at both speeds) and reduced stride length (p < 0.001 at both speeds), less knee flexion during stance and swing phases (p < 0.001 for both speeds) and less knee extension during stance phase (p < 0.024 for comfortable speed; p < 0.042 for fast speed). The TKR group also walked with less peak knee external rotation than controls at both speeds (p < 0.001 for both speeds). Both groups increased their velocity, cadence and stride length by a similar proportion when walking at fast speed. When walking at a faster speed, spatiotemporal gait parameters and knee motion are altered in a similar manner for both TKR patients and controls. However, at both walking speeds, TKR patients exhibit residual deficits 12 months following surgery.

  16. The influence of pain on knee motion in patients with osteoarthritis undergoing total knee arthroplasty.

    PubMed

    Bennett, Damien; Hanratty, Brian; Thompson, Neville; Beverland, David E

    2009-04-01

    Pain is the predominant symptom of degenerative knee arthritis and the main reason patients undergo total knee arthroplasty (TKA). Variation in patient response to pain has proved difficult to quantify. The effect of removing pain by testing TKA patients' range of motion (ROM) before and after the administration of anesthesia has not previously been analyzed. This study objectively quantifies the effect of eliminating pain on knee joint ROM for a typical group of TKA patients with osteoarthritis. We prospectively recruited 141 patients with osteoarthritis admitted for TKA to assess the inhibitory effect of pain on ROM. Passive maximum flexion, extension, and ROM were measured preoperatively before and after administration of anesthesia (spinal anesthetic followed by femoral and sciatic regional nerve blocks). Following pain abolition, passive maximum flexion increased by an average of 13.4 degrees (SD=11.9 degrees), passive maximum extension improved by an average of 3.0 degrees (SD=4.2 degrees), and passive ROM increased by an average of 16.4 degrees (SD=13.1 degrees). The change in each parameter was statistically significant (P<.0001). Improvements in flexion (P=.01) and ROM (P=.005) were significantly greater in women. Measurements taken before anesthesia reflect knee ROM that the patient will tolerate before pain becomes the limiting factor, while measurements taken after anesthesia is achieved suggest the knee ROM possible once pain is eliminated. Abolition of pain led to significant increases in knee flexion, extension, and ROM, suggesting that pain has a significant inhibitory effect on knee motion.

  17. Anterior opening wedge osteotomy of the proximal tibia for anterior knee pain in idiopathic hyperextension knees

    PubMed Central

    van Raaij, T. M.

    2006-01-01

    We analysed 20 patients with 24 knees affected by idiopathic genu recurvatum who were treated with an anterior opening wedge osteotomy of the proximal tibia because of anterior knee pain. We managed to attain full satisfaction in 83% of the patients with a mean follow-up of 7.4 years. The mean Hospital for Special Surgery score was 90.3 (range 70.5–99.5), and the mean Knee Society score score was 94.6 (70–100) for function and 87.7 (47–100) for pain. The mean Western Ontario and McMaster University Osteoarthritis Index score for knee function was 87.5 (42–100), for stiffness 82.8 (25–100) and for pain 87.3 (55–100). Radiographs showed a significant increase in posterior tibial slope of 9.4 deg and a significant decrease of patellar height according to the Blackburne–Peel method of 0.16 postoperatively. No cases of non-union, deep infection or compartment syndrome were seen. No osteoarthritic changes in the lateral or medial knee compartment were found with more than 5 years’ follow-up in 16 patients with 19 affected knees. Three out of the four dissatisfied patients had a patella infera which led to patellofemoral complaints. One patient in the study underwent a secondary superior displacement of the patella with excellent results. We conclude that in a selected group of patients with idiopathic genu recurvatum and anterior knee pain an opening wedge osteotomy of the proximal tibia can be beneficial. PMID:16521014

  18. Muscles that do not cross the knee contribute to the knee adduction moment and tibiofemoral compartment loading during gait.

    PubMed

    Sritharan, Prasanna; Lin, Yi-Chung; Pandy, Marcus G

    2012-10-01

    The aims of this study were to evaluate and explain the individual muscle contributions to the medial and lateral knee compartment forces during gait, and to determine whether these quantities could be inferred from their contributions to the external knee adduction moment. Gait data from eight healthy male subjects were used to compute each individual muscle contribution to the external knee adduction moment, the net tibiofemoral joint reaction force, and reaction moment. The individual muscle contributions to the medial and lateral compartment forces were then found using a least-squares approach. While knee-spanning muscles were the primary contributors, non-knee-spanning muscles (e.g., the gluteus medius) also contributed substantially to the medial compartment compressive force. Furthermore, knee-spanning muscles tended to compress both compartments, while most non-knee-spanning muscles tended to compress the medial compartment but unload the lateral compartment. Muscle contributions to the external knee adduction moment, particularly those from knee-spanning muscles, did not accurately reflect their tendencies to compress or unload the medial compartment. This finding may further explain why gait modifications may reduce the knee adduction moment without necessarily decreasing the medial compartment force.

  19. Comparison of Diagnostic Performance of Semi-Quantitative Knee Ultrasound and Knee Radiography with MRI: Oulu Knee Osteoarthritis Study.

    PubMed

    Podlipská, Jana; Guermazi, Ali; Lehenkari, Petri; Niinimäki, Jaakko; Roemer, Frank W; Arokoski, Jari P; Kaukinen, Päivi; Liukkonen, Esa; Lammentausta, Eveliina; Nieminen, Miika T; Tervonen, Osmo; Koski, Juhani M; Saarakkala, Simo

    2016-03-01

    Osteoarthritis (OA) is a common degenerative musculoskeletal disease highly prevalent in aging societies worldwide. Traditionally, knee OA is diagnosed using conventional radiography. However, structural changes of articular cartilage or menisci cannot be directly evaluated using this method. On the other hand, ultrasound is a promising tool able to provide direct information on soft tissue degeneration. The aim of our study was to systematically determine the site-specific diagnostic performance of semi-quantitative ultrasound grading of knee femoral articular cartilage, osteophytes and meniscal extrusion, and of radiographic assessment of joint space narrowing and osteophytes, using MRI as a reference standard. Eighty asymptomatic and 79 symptomatic subjects with mean age of 57.7 years were included in the study. Ultrasound performed best in the assessment of femoral medial and lateral osteophytes, and medial meniscal extrusion. In comparison to radiography, ultrasound performed better or at least equally well in identification of tibio-femoral osteophytes, medial meniscal extrusion and medial femoral cartilage morphological degeneration. Ultrasound provides relevant additional diagnostic information on tissue-specific morphological changes not depicted by conventional radiography. Consequently, the use of ultrasound as a complementary imaging tool along with radiography may enable more accurate and cost-effective diagnostics of knee osteoarthritis at the primary healthcare level.

  20. Exercise Alters Gait Pattern but Not Knee Load in Patients with Knee Osteoarthritis

    PubMed Central

    Lin, Yi-Jia; Chang, Chao-Chin; Chou, You-Cai

    2016-01-01

    Six female patients with bilateral medial knee OA and 6 healthy controls were recruited. Patients with knee OA received a 6-week physiotherapist-supervised and home-based exercise program. Outcome measures, including the Western Ontario and McMaster Universities Arthritis Index and Short Form-36 Health Survey as well as objective biomechanical indices were obtained at baseline and follow-up. After treatment, no significant difference was observed in the knee abductor moment (KAM), lever arm, and ground reaction force. We, however, observed significantly improved pain and physical function as well as altered gait patterns, including a higher hip flexor moment and hip extension angle with a faster walking speed. Although KAM was unchanged, patients with bilateral knee OA showed an improved walking speed and altered the gait pattern after 6 weeks of supervised exercise. This finding suggests that the exercise intervention improves proximal joint mechanics during walking and can be considered for patients with bilateral knee OA. Non-weight-bearing strengthening without external resistance combined with stretching exercise may be an option to improve pain and function in individuals with OA who cannot perform high resistance exercises owing to pain or other reasons. PMID:27725941

  1. In vivo determination of total knee arthroplasty kinematics

    SciTech Connect

    Komistek, Richard D; Mahfouz, Mohamed R; Bertin, Kim; Rosenberg, Aaron; Kennedy, William

    2008-01-01

    The objective of this study was to determine if consistent posterior femoral rollback of an asymmetrical posterior cruciate retaining (PCR) total knee arthroplasty was mostly influenced by the implant design, surgical technique, or presence of a well-functioning posterior cruciate ligament (PCL). Three-dimensional femorotibial kinematics was determined for 80 subjects implanted by 3 surgeons, and each subject was evaluated under fluoroscopic surveillance during a deep knee bend. All subjects in this present study having an intact PCL had a well-functioning PCR knee and experienced normal kinematic patterns, although less in magnitude than the normal knee. In addition, a surprising finding was that, on average, subjects without a PCL still achieved posterior femoral rollback from full extension to maximum knee flexion. The findings in this study revealed that implant design did contribute to the normal kinematics demonstrated by subjects having this asymmetrical PCR total knee arthroplasty.

  2. Knee Pain and a Prior Injury Are Associated With Increased Risk of a New Knee Injury: Data from the Osteoarthritis Initiative

    PubMed Central

    Driban, Jeffrey B.; Lo, Grace H.; Eaton, Charles B.; Price, Lori Lyn; Lu, Bing; McAlindon, Timothy E.

    2015-01-01

    Objectives We explored if knee pain or a history of knee injury was associated with a knee injury in the following 12 months. Methods We conducted longitudinal knee-based analyses among knees in the Osteoarthritis Initiative. We included both knees of all participants who had at least one follow-up visit with complete data. Our first sets of exposures were knee pain (chronic knee symptoms and severity) at baseline, 12-month, 24-month, and 36-month visits. Another exposure was a history of injury, which we defined as a self-reported injury at any time prior to baseline, 12-month, 24-month, or 36-month visits. The outcome was self-reported knee injury during the past year at 12-month, 24-month, 36-month, and 48-month visits. We evaluated the association between ipsilateral and contralateral knee pain or history of injury and a new knee injury within 12 months of the exposure using generalized linear mixed model for repeated binary outcomes. Results A knee with reported chronic knee symptoms or ipsilateral or contralateral history of an injury was more likely to experience a new knee injury in the following 12 months than a knee without chronic knee symptoms (odds ratio [OR]=1.84, 95% confidence interval [CI]=1.57, 2.16) or prior injury (prior ipsilateral knee injury OR=1.81, 95% CI=1.56, 2.09; prior contralateral knee injury OR=1.43, 95% CI=1.23, 1.66). Conclusion Knee pain and a history of injury are associated with new knee injuries. It may be beneficial for individuals with knee pain or a history of injury to participate in injury prevention programs. PMID:26034152

  3. Anterior cruciate ligament reconstruction and knee osteoarthritis

    PubMed Central

    Paschos, Nikolaos K

    2017-01-01

    Anterior cruciate ligament (ACL) injury is a traumatic event that can lead to significant functional impairment and inability to participate in high-level sports-related activities. ACL reconstruction is considered the treatment of choice for symptomatic ACL-deficient patients and can assist in full functional recovery. Furthermore, ACL reconstruction restores ligamentous stability to normal, and, therefore, can potentially fully reinstate kinematics of the knee joint. As a consequence, the natural history of ACL injury could be potentially reversed via ACL reconstruction. Evidence from the literature is controversial regarding the effectiveness of ACL reconstruction in preventing the development of knee cartilage degeneration. This editorial aims to present recent high-level evidence in an attempt to answer whether ACL injury inevitably leads to osteoarthritis and whether ACL reconstruction can prevent this development or not. PMID:28361013

  4. Ultrasonographic scan in knee pain in athletes.

    PubMed Central

    Maffulli, N; Regine, R; Carrillo, F; Minelli, S; Beaconsfield, T

    1992-01-01

    Fifty-two knees were examined using real-time high-definition ultrasonography with a 7.5 MHz probe. The extra-articular structures were easily visualized and diagnosis of patellar tendon lesions and Baker's cysts formulated. While the meniscal cartilages were shown as a homogeneous triangular structure between the femoral condyle and the tibial plateau, no lesions were detected. Deeper intra-articular structures, such as the cruciate ligaments, were not shown by the scan, thus their evaluation was not possible. Given its low cost, wide availability, non-invasiveness and patients' acceptability of the technique, ultrasonography may play an important role in the diagnosis of soft tissue lesions in and around the knee joint. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:1623366

  5. Mobile bearings in primary knee arthroplasty.

    PubMed

    Vertullo, C J; Easley, M E; Scott, W N; Insall, J N

    2001-01-01

    Mobile-bearing knee arthroplasty (MBKA) has potential advantages compared with conventional fixed-bearing total knee arthroplasty (TKA). By allowing unconstrained axial rotation, MBKA can offer greater articular conformity without an increased probability of loosening due to increased axial torque. Increased articular conformity minimizes polyethylene contact stresses, thereby reducing linear wear and subsurface fatigue failure. Axial rotation of the platform also enables self-correction of tibial component malrotation. Despite these advantages, the long-term clinical results obtained with current MBKA devices are similar to those obtained with well-designed fixed-bearing TKA prostheses, with no data suggesting their superiority. The disadvantages of MBKA include bearing dislocation and breakage, soft-tissue impingement, a steep technique learning curve, and concerns about volumetric wear. Hypothetically, longer-term follow-up of MBKA results may reveal a significant difference from fixed-bearing TKA results as the fatigue failure threshold of incongruent polyethylene is exceeded.

  6. Bilateral pigmented villonodular synovitis of the knee

    PubMed Central

    Shah, Samir H.; Porrino, Jack A.; Green, John R.; Chew, Felix S.

    2015-01-01

    Pigmented villonodular synovitis is a disorder resulting in a villous, nodular, or villonodular proliferation of the synovium, with pigmentation related to the presence of hemosiderin. These lesions are almost exclusively benign with rare reports of malignancy. Pigmented villonodular synovitis can occur in a variety of joints and at any age but most often occurs within the knee in the young adult. Pigmented villonodular synovitis is a rare disease entity, and bilateral synchronous or metachronous involvement of a joint is even more uncommon, with few reports previously described in the literature. We present a case of pigmented villonodular synovitis involving both the right and left knee in the same patient, with radiographic imaging, magnetic resonance imaging, photograph and video intraoperative imaging, and pathologic correlation. PMID:26649121

  7. Be aware of wood in the knee

    PubMed Central

    O’Connell, Rachel Louise; Fageir, Mazin M; Addison, Anthony

    2011-01-01

    The authors report a case of a 7-year-old boy who sustained a penetrating injury of a splinter of wood to the knee. Arthroscopic examination, removal of visualised foreign material and washout did not alleviate the symptoms of pain and swelling in its entirety. Microbiology cultures also failed to determine the cause of the on-going symptoms. Five days later, the patient underwent a mini arthrotomy through a lateral incision, which demonstrated synovitis, and removal of the remaining embedded foreign body from the lateral condyle. Although the authors advocate arthroscopy as the surgeon’s first choice for removal of a foreign body from the knee, a mini-arthrotomy should also be considered to facilitate superior visualisation and easier instrumentation to remove embedded foreign bodies. PMID:22669952

  8. Posterolateral Corner of the Knee: Current Concepts

    PubMed Central

    Chahla, Jorge; Moatshe, Gilbert; Dean, Chase S.; LaPrade, Robert F.

    2016-01-01

    Injuries to the posterolateral corner (PLC) comprise a significant portion of knee ligament injuries. A high index of suspicion is necessary when evaluating the injured knee to detect these sometimes occult injuries. Moreover, a thorough physical examination and a comprehensive review of radiographic studies are necessary to identify these injuries. In this sense, stress radiographs can help to objectively determine the extent of these lesions. Non-operative and operative treatment options have been reported depending on the extent of the injury. Complete PLC lesions rarely heal with non-operative treatment, and are therefore most often treated surgically. The purpose of this article was to review the anatomy and clinically relevant biomechanics, diagnosis algorithms, treatment and rehabilitation protocols for PLC injuries. PMID:27200384

  9. Knee osteoarthritis: Therapeutic alternatives in primary care

    PubMed Central

    Evaniew, Allison L; Evaniew, Nathan

    2017-01-01

    AIM To discusses pharmacological and non-pharmacological therapeutic alternatives for managing knee osteoarthritis in primary care by primary health care nurse practitioners. METHODS A case example is presented, the evidence-based guideline recommendations of the Osteoarthritis Research Society International and the American Academy of Orthopaedic Surgeons are reviewed, and a plan of care is developed. RESULTS Osteoarthritis is the most common form of arthritis seen in primary care, and it is a major public health issue because the aging population and widespread obesity have drastically increased incidence. Osteoarthritis is clinically associated with escalating chronic pain, physical disability, and decreased quality of life. Early diagnosis of mild osteoarthritis in relatively young patients presents an opportunity for primary health care providers to manage pain, increase quality of life, and decrease risk of disability. CONCLUSION Primary health care providers can implement these recommendations in their own practices to provide care to patients with knee osteoarthritis based on current best evidence. PMID:28251070

  10. Fracture Blisters After Primary Total Knee Arthroplasty.

    PubMed

    Halawi, Mohamad J

    2015-08-01

    Fracture blisters are tense vesicles that arise on markedly swollen skin overlying traumatized soft tissue. While this relatively uncommon complication has been well described in the trauma literature, this article reports for the first time a case of fracture blisters after primary total knee arthroplasty. The fracture blisters developed within 36 hours of surgery and were associated with profound swelling and erythema. There was no evidence of vascular injury, compartment syndrome, iatrogenic fracture, or deep venous thrombosis. The patient was treated with leg elevation, loosely applied nonadhesive dressings, and a short course of oral antibiotics after skin desquamation. Blood-filled blisters required longer time to reepithelialization than fluid-filled blisters. Knee stiffness developed because of pain and fear of participation with physical therapy, but the patient was able to resume intensive rehabilitation after resolution of the blisters. Patient factors, surgical factors, and review of the literature are discussed.

  11. Tuberculosis of the knee in children.

    PubMed

    Lee, A S; Campbell, J A; Hoffman, E B

    1995-03-01

    We reviewed 33 children with tuberculosis of the knee treated during the period from 1979 to 1991. All were treated with triple chemotherapy, using rifampicin, isoniazid and pyrazinamide for nine months. No patient had a synovectomy; surgery was limited to open biopsy or salvage procedures such as posterior release and arthrodesis for late stages of the disease. The radiological appearance of the knee at presentation predicted the outcome. The 30 patients with stage-1 (normal) or stage-2 (osteomyelitic) disease had excellent or good results; the three with narrowed joint spaces in stage 3 or stage 4 (arthritic) had fair or poor results. Early active mobilisation, as against long-term immobilisation, seemed to have no effect on the outcome of stage-1 or stage-2 disease.

  12. Knee Injuries in American Football: An Epidemiological Review.

    PubMed

    Rothenberg, Paul; Grau, Luis; Kaplan, Lee; Baraga, Michael G

    Football has the highest injury rate amongst popular American sports. Of those injuries that end seasons or careers, the knee is the most common culprit. This is of particular concern because knee injuries are most common in football. This article reviews 4 of the most common knee injuries in American football, with emphasis on epidemiology, risk factors, and treatment outcomes. The injuries reviewed are tears of the anterior cruciate ligament, medial collateral ligament, medial patellofemoral ligament, and posterior cruciate ligament.

  13. Clinical strategies for addressing muscle weakness following knee injury.

    PubMed

    Pietrosimone, Brian; Blackburn, J Troy; Harkey, Matthew S; Luc, Brittney A; Pamukoff, Derek N; Hart, Joe M

    2015-04-01

    Muscle strength is a determinate of physical function and increasing muscle strength is an important clinical goal for patients with knee injury. This article discusses the emerging evidence regarding a novel rehabilitation strategy that uses disinhibitory modalities to increase neuromuscular activation in conjunction with traditional muscle strengthening for the purpose of maximizing strength gains following acute knee injury or surgery and in patients with knee osteoarthritis. The use of disinhibitory modalities and specific types of neuromuscular training for clinically maximizing strength are discussed.

  14. Stress fracture of the proximal fibula after total knee arthroplasty.

    PubMed

    Vaish, Abhishek; Vaishya, Raju; Agarwal, Amit Kumar; Vijay, Vipul

    2016-04-22

    We report a rare case of proximal fibular fatigue fracture developing 14 years after total knee arthroplasty in a known case of rheumatoid arthritis. A valgus deformity of the knee can put abnormal stress on the upper fibula leading to its failure. We believe that, as the fibula acts as an important lateral strut, its disruption due to a fracture led to rapid progress of the valgus deformity of the knee in this patient.

  15. Unusual lesions that distend the knee joint: pictorial essay*

    PubMed Central

    de Lima, Luana T. Barros; de Albuquerque Filho, Eolo Santana; Batista, Laecio Leitão; de Moraes, Talita Peixoto; Pereira, Bruno Perez Guedes

    2016-01-01

    The high number of knee imaging exams at radiology clinics, together with the wide variety of knee disorders, calls for expanding the knowledge about the less common lesions seen in routine diagnostic practice. The purpose of this pictorial essay was to illustrate unusual lesions that distend the knee joint, selected by relevance and evaluated with multiple imaging modalities, including X-ray, computed tomography, and magnetic resonance imaging, as well as to perform a brief review of the literature. PMID:27818547

  16. Mathematical modeling of the human knee joint

    SciTech Connect

    Ricafort, Juliet

    1996-05-01

    A model was developed to determine the forces exerted by several flexor and extensor muscles of the human knee under static conditions. The following muscles were studied: the gastrocnemius, biceps femoris, semitendinosus, semimembranosus, and the set of quadricep muscles. The tibia and fibula were each modeled as rigid bodies; muscles were modeled by their functional lines of action in space. Assumptions based on previous data were used to resolve the indeterminacy.

  17. Metal Hypersensitivity and Total Knee Arthroplasty.

    PubMed

    Lachiewicz, Paul F; Watters, Tyler Steven; Jacobs, Joshua J

    2016-02-01

    Metal hypersensitivity in patients with a total knee arthroplasty (TKA) is a controversial topic. The diagnosis is difficult, given the lack of robust clinical validation of the utility of cutaneous and in vitro testing. Metal hypersensitivity after TKA is quite rare and should be considered after eliminating other causes of pain and swelling, such as low-grade infection, instability, component loosening or malrotation, referred pain, and chronic regional pain syndrome. Anecdotal observations suggest that two clinical presentations of metal hypersensitivity may occur after TKA: dermatitis or a persistent painful synovitis of the knee. Patients may or may not have a history of intolerance to metal jewelry. Laboratory studies, including erythrocyte sedimentation rate, C-reactive protein level, and knee joint aspiration, are usually negative. Cutaneous and in vitro testing have been reported to be positive, but the sensitivity and specificity of such testing has not been defined. Some reports suggest that, if metal hypersensitivity is suspected and nonsurgical measures have failed, then revision to components fabricated of titanium alloy or zirconium coating can be successful in relieving symptoms. Revision should be considered as a last resort, however, and patients should be informed that no evidence-based medicine is available to guide the management of these conditions, particularly for decisions regarding revision. Given the limitations of current testing methods, the widespread screening of patients for metal allergies before TKA is not warranted.

  18. Knee Articular Cartilage Repair and Restoration Techniques

    PubMed Central

    Richter, Dustin L.; Schenck, Robert C.; Wascher, Daniel C.; Treme, Gehron

    2015-01-01

    Context: Isolated chondral and osteochondral defects of the knee are a difficult clinical challenge, particularly in younger patients for whom alternatives such as partial or total knee arthroplasty are rarely advised. Numerous surgical techniques have been developed to address focal cartilage defects. Cartilage treatment strategies are characterized as palliation (eg, chondroplasty and debridement), repair (eg, drilling and microfracture [MF]), or restoration (eg, autologous chondrocyte implantation [ACI], osteochondral autograft [OAT], and osteochondral allograft [OCA]). Evidence Acquisition: PubMed was searched for treatment articles using the keywords knee, articular cartilage, and osteochondral defect, with a focus on articles published in the past 5 years. Study Design: Clinical review. Level of Evidence: Level 4. Results: In general, smaller lesions (<2 cm2) are best treated with MF or OAT. Furthermore, OAT shows trends toward greater longevity and durability as well as improved outcomes in high-demand patients. Intermediate-size lesions (2-4 cm2) have shown fairly equivalent treatment results using either OAT or ACI options. For larger lesions (>4 cm2), ACI or OCA have shown the best results, with OCA being an option for large osteochondritis dissecans lesions and posttraumatic defects. Conclusion: These techniques may improve patient outcomes, though no single technique can reproduce normal hyaline cartilage. PMID:26502188

  19. Accuracy of clinical diagnosis in knee arthroscopy.

    PubMed Central

    Brooks, Stuart; Morgan, Mamdouh

    2002-01-01

    A prospective study of 238 patients was performed in a district general hospital to assess current diagnostic accuracy rates and to ascertain the use and the effectiveness of magnetic resonance imaging (MRI) scanning in reducing the number of negative arthroscopies. The pre-operative diagnosis of patients listed for knee arthroscopy was medial meniscus tear 94 (40%) and osteoarthritis 59 (25%). MRI scans were requested in 57 patients (24%) with medial meniscus tear representing 65% (37 patients). The correlation study was done between pre-operative diagnosis, MRI and arthroscopic diagnosis. Clinical diagnosis was as accurate as the MRI with 79% agreement between the preoperative diagnosis and arthroscopy compared to 77% agreement between MRI scan and arthroscopy. There was no evidence, in this study, that MRI scan can reduce the number of negative arthroscopies. Four normal MRI scans had positive arthroscopic diagnosis (two torn medial meniscus, one torn lateral meniscus and one chondromalacia patella). Out of 240 arthroscopies, there were only 10 normal knees (negative arthroscopy) representing 4% of the total number of knee arthroscopies; one patient of those 10 cases had MRI scan with ACL rupture diagnosis. Images Figure 1 Figure 2 PMID:12215031

  20. Periprosthetic fractures around total knee arthroplasty

    PubMed Central

    Sarmah, SS; Patel, S; Reading, G; El-Husseiny, M; Douglas, S; Haddad, FS

    2012-01-01

    INTRODUCTION The number of total knee arthroplasties performed continues to rise annually and it would be expected that complications, which include periprosthetic fractures, will also therefore become more commonplace. This article reviews the current literature regarding this injury and identifies the treatment principles that enable patients to regain optimal function. METHODS A comprehensive search of the Pubmed and Embase™ databases was performed to identify relevant articles. Keywords and MeSH (Medical Subject Headings) terms included in the search strategy were ‘periprosthetic fracture(s)’, ‘femur’, ‘tibia’, ‘patella(r)’, ‘complication(s)’, ‘failure(s)’, ‘risk(s)’, ‘prevalence’, ‘incidence’, ‘epidemiology’ and ‘classification(s)’. The search was limited to all articles published in English and reference lists from the original articles were reviewed to identify pertinent articles to include in this review. A total number of 43 studies were identified. RESULTS Common treatment aims have been identified when managing patients with a periprosthetic fracture around total knee arthoplasty. The main criterion that determines which option to choose is the degree of remaining bone stock and the amount of fracture displacement. CONCLUSIONS Treatment of a periprosthetic fracture around total knee arthroplasty will either be non-operative, osteosynthesis or revision arthroplasty. It is imperative that a suitable option is chosen and based on the published literature, pathways are outlined to aid the surgeon. PMID:22943223

  1. [SECOT consensus on painful knee replacement].

    PubMed

    Vaquero, J; Macule, F; Bello, S; Chana, F; Forriol, F

    2013-01-01

    The opinions of 21 experts in knee surgery were evaluated in this study, using a DELPHI questionnaire method in two successive rounds, on 64 controversial scenarios that covered both the diagnosis and possible treatment of painful knee replacements. The level of consensus was significantly unanimous in 42 items and of the design in 5, with no agreement in 17 of the questions presented. light of the published scientific evidence, the surgeons who took part showed to have a notable level of information on the most effective diagnostic tests, although, it should be pointed out that there was a lack of confidence in the possibility of ruling out an infection when the erythrocyte sedimentation rate and the C-reactive protein were within normal values, which have been demonstrated in the literature to have a high negative predictive value As regards the treatments to employ in the different situations, the responses of the expert panel were mainly in agreement with the data in the literature. The conclusions of this consensus may help other surgeons when they are faced with a painful knee prosthesis.

  2. Metal Hypersensitivity and Total Knee Arthroplasty

    PubMed Central

    Lachiewicz, Paul F.; Watters, Tyler Steven; Jacobs, Joshua J.

    2015-01-01

    Metal hypersensitivity in patients with a total knee arthroplasty (TKA) is a controversial topic. The diagnosis is difficult, given the lack of robust clinical validation of the utility of cutaneous and in vitro testing. Metal hypersensitivity after TKA is quite rare and should be considered after eliminating other causes of pain and swelling, such as low-grade infection, instability, component loosening or malrotation, referred pain, and chronic regional pain syndrome. Anecdotal observations suggest that two clinical presentations of metal hypersensitivity may occur after TKA: dermatitis or a persistent painful synovitis of the knee. Patients may or may not have a history of intolerance to metal jewelry. Laboratory studies, including erythrocyte sedimentation rate, C-reactive protein level, and knee joint aspiration, are usually negative. Cutaneous and in vitro testing have been reported to be positive, but the sensitivity and specificity of such testing has not been defined. Anecdotal reports suggest that, if metal hypersensitivity is suspected and nonsurgical measures have failed, then revision to components fabricated of titanium alloy or zirconium coating can be successful in relieving symptoms. Revision should be considered as a last resort, however, and patients should be informed that no evidence-based medicine is available to guide the management of these conditions, particularly for decisions regarding revision. Given the limitations of current testing methods, the widespread screening of patients for metal allergies before TKA is not warranted. PMID:26752739

  3. Glanzmann's Thrombasthenia Diagnosed following Knee Arthroscopy

    PubMed Central

    Zvijac, John E.; Ammus, Sharhabil S.; Aran, Fernando; Kiebzak, Gary M.

    2015-01-01

    A 41-year-old man with an unremarkable medical history presented with a painful knee after a sports injury. He was diagnosed with a medial meniscal tear. Symptoms did not abate after 6 months of physical therapy, and he underwent arthroscopic partial medial meniscectomy. A week after beginning physical therapy he experienced a knee effusion, decreased ROM, and inability to flex his quadriceps. His knee was aspirated. Blood tests were ordered and his complete blood count, liver functions tests, and INR/PTT were normal. The patient had recurrent effusions requiring three additional joint aspirations. Ten weeks after the initial surgery, the patient underwent a second arthroscopy, during which a hematoma was removed and a synovectomy performed. The patient continued bleeding from the incisions after portals were sutured, and he was admitted to the hospital. A hematologist was consulted and comprehensive platelet aggregation testing revealed previously undiagnosed Glanzmann's thrombasthenia. The patient began treatment with platelet infusions and desmopressin and progressed to a full recovery. Clinical suspicion for surgical patients with unusual repetitive postoperative bleeding should include previously undetected rare bleeding disorders even in adults. PMID:26000186

  4. Glanzmann's Thrombasthenia Diagnosed following Knee Arthroscopy.

    PubMed

    Zvijac, John E; Ammus, Sharhabil S; Aran, Fernando; Kiebzak, Gary M

    2015-01-01

    A 41-year-old man with an unremarkable medical history presented with a painful knee after a sports injury. He was diagnosed with a medial meniscal tear. Symptoms did not abate after 6 months of physical therapy, and he underwent arthroscopic partial medial meniscectomy. A week after beginning physical therapy he experienced a knee effusion, decreased ROM, and inability to flex his quadriceps. His knee was aspirated. Blood tests were ordered and his complete blood count, liver functions tests, and INR/PTT were normal. The patient had recurrent effusions requiring three additional joint aspirations. Ten weeks after the initial surgery, the patient underwent a second arthroscopy, during which a hematoma was removed and a synovectomy performed. The patient continued bleeding from the incisions after portals were sutured, and he was admitted to the hospital. A hematologist was consulted and comprehensive platelet aggregation testing revealed previously undiagnosed Glanzmann's thrombasthenia. The patient began treatment with platelet infusions and desmopressin and progressed to a full recovery. Clinical suspicion for surgical patients with unusual repetitive postoperative bleeding should include previously undetected rare bleeding disorders even in adults.

  5. Radiological and clinical effect of prosthesis design in varus knees?

    PubMed Central

    Isyar, Mehmet; Guler, Olcay; Cakmak, Selami; Kara, Adnan; Yalcin, Sercan; Mahirogullari, Mahir

    2015-01-01

    Purpose The aim of the study is to investigate the efficacy of the prosthesis design used in total knee arthroplasty in patients with varus malalignment. Methods After exclusion criteria we classified 90 patients underwent total knee arthroplasty according to prosthesis used into two groups: posterior cruciate ligament substituting and retaining. Mean follow up period was 25–98 months. We evaluated preoperative and postoperative radiological and as well as clinical parameters such as pain, knee function, flexion deformity. Results We found statistically significant difference in both groups in terms of deformity correction (p = 0.000). Conclusion Prosthesis design affects radiological outcomes in varus knees. PMID:26566321

  6. MIS unicondylar knee arthroplasty: surgical approach and early results.

    PubMed

    Gesell, Mark W; Tria, Alfred J

    2004-11-01

    Unicondylar arthroplasty of the knee has seen a resurgence of interest in the United States. The principles of unicondylar arthroplasty of the knee are different from those for total knee arthroplasty, allowing replacement of only the affected joint compartment with less bone loss. Minimally invasive surgery allows for less soft tissue dissection with the potential for less morbidity. The key question is: will the changes associated with the minimally invasive surgery procedure improve the clinical results of the standard unicondylar arthroplasty of the knee or will the changes make the procedure too difficult and lead to an increasing failure rate? This study reviews the surgical technique and presents the 2 to 4 year results of the minimally invasive unicondylar arthroplasty of the knee 47 knees in 41 patients. The average range of motion increased from 121 degrees -132 degrees . The Knee Society pain score improved from 45-80 and the function score improved from 47-78. Only one knee has been revised. With proper patient selection, minimally invasive unicondylar arthroplasty of the knee allows for results that are at least equal to those of the standard open procedure at 2 to 4 years after the surgery.

  7. Mobile Sensor Application for Kinematic Detection of the Knees

    PubMed Central

    Suputtitada, Areerat; Khovidhungij, Watcharapong

    2015-01-01

    Objective To correctly measure the knee joint angle, this study utilized a Qualisys motion capture system and also used it as the reference to assess the validity of the study's Inertial Measurement Unit (IMU) system that consisted of four IMU sensors and the Knee Angle Recorder software. The validity was evaluated by the root mean square (RMS) of different angles and the intraclass correlation coefficient (ICC) values between the Qualisys system and the IMU system. Methods Four functional knee movement tests for ten healthy participants were investigated, which were the knee flexion test, the hip and knee flexion test, the forward step test and the leg abduction test, and the walking test. Results The outcomes of the knee flexion test, the hip and knee flexion test, the forward step test, and the walking test showed that the RMS of different angles were less than 6°. The ICC values were in the range of 0.84 to 0.99. However, the leg abduction test showed a poor correlation in the measurement of the knee abduction-adduction movement. Conclusion The IMU system used in this study is a new good method to measure the knee flexion-extension movement. PMID:26361597

  8. The Unique Macroscopic Appearance of Gouty Arthritis of the Knee.

    PubMed

    Mittl, Gregory S; Zuckerman, Joseph D

    2015-07-01

    Patients with significant gouty arthritis can develop disabling joint pain secondary to monosodium urate (MSU) articular deposition. We report a case of white, chalky MSU crystal deposition covering the articular surfaces of the knee as discovered by total knee arthroplasty. A 65-year-old male with a history of gout presented with bilateral knee pain. His radiographic imaging was negative for gouty tophi, and he elected to undergo left total knee arthroplasty. Intraoperatively a distinct chalky, white paste consistent with MSU deposition was observed covering the articular surfaces of the knee consistent with the diagnosis of gouty arthritis. Gout is the most common inflammatory arthritis affecting more than 3 million people in the USA. The inflammation results from the phagocytosis of monosodium urate crystals (MSU) and the release of inflammatory cytokines within the joint. Gout progresses from acute to chronic over many years and frequently causes chronic arthropathy. When significant knee pain and disability is associated with gouty arthropathy, total knee arthroplasty is certainly an option. The pathological appearance of gouty joints is characteristic. Macroscopic examination of joints affected by gout reveals a nodular, white, chalky appearance. Polarized microscopy of gout demonstrates negative birefringent needle-shaped MSU crystals. In this case report, we describe the characteristic chalky, white MSU deposit that covers the articular surfaces of a knee joint in a patient with a history of gout undergoing total knee arthroplasty. The investigators have obtained the patient's informed written consent for print and electronic publication of the case report.

  9. Relationship between ultrastructure and biomechanical properties of the knee meniscus.

    PubMed

    Gabrion, A; Aimedieu, P; Laya, Z; Havet, E; Mertl, P; Grebe, R; Laude, M

    2005-12-01

    The purpose of this study was to determine the biomechanical properties of the knee meniscus and to relate them to its ultrastructure. The knee joint menisci are semicircular, fibrocartilaginous structures interposed between the femoral and tibial condyles. For a long time, they were considered to be embryologic vestiges. This study describes the response of the knee joint meniscus to circumferential, radial and axial compressive forces. The results show an anisotropic response of the knee joint meniscus to unconfined compression. The Young's modulus increased approximately twofold between vertical and circumferential or radial directions with a 10 mm/min-compression rate. This response is probably a direct consequence of the orientation of collagen fibres.

  10. Low contact stress (LCS) complete knee system in revision surgery.

    PubMed

    Lippe, Craig N; Crossett, Lawrence S

    2006-09-01

    Revision total knee arthroplasty (TKA) should offer the same benefits to patients as primary TKA. As in primary TKA, a main objective of revision TKA is to reduce pain and restore functional range of motion. There are several potential causes of total knee failure, but the principles of repairing each of them is similar. The long-term success of the low contact stress knee system in primary TKA is well established, and clinical evidence for revision TKA with the low contact stress knee is promising.

  11. Chronic knee extensor mechanism lesions in total knee arthroplasty: a literature review

    PubMed Central

    COTTINO, UMBERTO; DELEDDA, DAVIDE; ROSSO, FEDERICA; BLONNA, DAVIDE; BONASIA, DAVIDE EDOARDO; ROSSI, ROBERTO

    2016-01-01

    Knee extensor mechanism rupture is a serious complication of total knee arthroplasty (TKA). Its prevalence ranges from 1 to 10% and it is commonly observed as a chronic multifactorial pathology with the patellar tendon as the most common site of rupture. Knee extensor mechanism reconstruction can be performed using allogenic or synthetic grafts. In the literature it is still not clear whether one of these techniques is superior to the other and the choice is usually tailored to the patient case by case. Allografts allow better restoration of the anatomical landmarks, whereas the mesh technique is more reproducible and the graft does not elongate over time. Allografts carry an increased risk of infection compared with synthetic reconstructions, while the mesh technique is cheaper and more readily available. In this paper, we review the etiology, diagnosis and treatment of this pathology, drawing on the most recent literature. PMID:27900308

  12. Knee arthrodesis as limb salvage for complex failures of total knee arthroplasty.

    PubMed

    Kuchinad, Raul; Fourman, Mitchell S; Fragomen, Austin T; Rozbruch, S Robert

    2014-11-01

    Patients with multiple failures of total knee arthroplasty (TKA) are challenging limb salvage cases. Twenty one patients over the last 10 years were referred to our service for knee fusion by arthroplasty surgeons who felt they were not candidates for revision TKA. Active infection was present in 76.2% and total bone loss averaged 6.6 cm. Lengthening was performed in 7/22 patients. Total time in Ilizarov frames was 9 months, with 93.3% union. Patients treated with IM fusion nails had 100% union. Average LLD increased from 3.6 to 4.5 cm following intervention, while those with concurrent lengthening improved to 1.6 cm. Findings suggest that bone loss and the soft-tissue envelope dictate knee fusion method, and multiple techniques may be needed. A treatment algorithm is presented.

  13. Clinical examination of the knee: know your tools for diagnosis of knee injuries

    PubMed Central

    2011-01-01

    The clinical evaluation of the knee is a fundamental tool to correctly address diagnosis and treatment, and should never be replaced by the findings retrieved by the imaging studies carried on the patient. Every surgeon has his own series of exams with whom he is more confident and on whom he relies on for diagnosis. Usually, three sets of series are used: one for patello-femoral/extensor mechanism pathologies; one for meniscal and chondral (articular) lesions; and one for instability evaluation. This review analyses the most commonly used tests and signs for knee examination, outlining the correct way to perform the test, the correct interpretation of a positive test and the best management for evaluating an injured knee both in the acute and delayed timing. PMID:22035381

  14. Above knee amputation following total knee arthroplasty: when enough is enough.

    PubMed

    Khanna, Vickas; Tushinski, Daniel M; Soever, Leslie J; Vincent, Alex D; Backstein, David J

    2015-04-01

    In some cases, above knee amputation (AKA) for a chronically infected total knee arthroplasty is the only option. The purpose of this study was to assess patient satisfaction following AKA and to identify factors which may be indicative of successful outcome following AKA. A review was performed of 7 patients who underwent an AKA for a recurrent peri-prosthetic knee infection. Patient satisfaction was gauged through a modified questionnaire. All patients were satisfied with their AKA and 6 of 7 stated that they would have chosen an amputation earlier. Greater than 6 attempts at limb-salvage and failed gastrocnemius flap were identified by expert opinion as possible poor prognostic factors. Despite poor function, patients with chronically infected TKAs are satisfied following an AKA.

  15. Knee joint kinematics, fixation and function related to joint area design in total knee arthroplasty.

    PubMed

    Uvehammer, J

    2001-02-01

    The aim was to study the influence of different designs of the joint area on tibial component fixation, kinematics and clinical outcome after a cemented total knee arthroplasty (TKA). The HSS score and a special questionnaire were used at the clinical examination. Conventional radiography was done to record the positioning of the implants and development of radiolucencies. The migration and inducible displacement were evaluated using radiostereometry (RSA). The kinematics of the knee during active extension was studied using dynamic RSA. In randomised and prospective studies 87 knees in 83 patients (28 male, 55 female, age 69, range 50-83) received an AMK (DePuy, Johnson & Johnson) TKA. The patients were divided into two groups. In group 1 the patients had varus/valgus deformities of < or = 5 degrees and the PCL was retained. The PCL was resected in group 2 where the patients had deformities exceeding 5 degrees and/or fixed flexion deformities of more than 10 degrees. In group 1 a flat (F, n = 20) or a concave (C, n = 20) design was implanted (study 3). In group 2 (study 4) the patients received a concave (n = 25) or a posterior-stabilised (PS, n = 22) tibial plateau. The migration of the tibial component, positioning of the prosthesis, development of radiolucencies and the clinical outcome was evaluated after 1 and 2 years. Twenty-two patients (11 F, 11 C) in group 1 (study 1) and 22 knees in 20 patients in group 2 (study 2, 11 C, 11 PS) were examined 1 year post-operatively to evaluate the kinematics of the knee. Eleven normals served as controls. During active extension of the knee the inducible displacements of the tibial component were recorded in 16 knees (15 patients). Based on successful RSA examinations 5 knees (4 F, 1 C) from group 1 and 11 knees (5 C, 6 PS) from group 2 were selected (study 5). Abnormal kinematics and especially increased AP translations compared to normals (p < 0.0005) were recorded in all designs. The concave design showed the widest

  16. Long-Term Clinical Outcomes and Survivorship of Revision Total Knee Arthroplasty with Use of a Constrained Condylar Knee Prosthesis.

    PubMed

    Kim, Young-Hoo; Park, Jang-Won; Kim, Jun-Shik; Oh, Hyun-Keun

    2015-10-01

    The purpose of this study was to determine long-term clinical and radiographic results. One hundred and ninety-four patients (228 knees) underwent revision TKA with use of a constrained condylar knee prosthesis. The mean duration of follow-up was 14.6 years (range, 11 to 16 years). The mean pre-revision Knee Society knee scores (43.5 points) and function scores (47.0 points), and Western Ontario and McMaster Universities Osteoarthritis index scores (88 points) were improved significantly (P=0.002) to 85.6, 68.5, and 25 points, respectively, at 14.6 years follow-up. Eighteen knees (8%) had re-revision. Four knees were re-revised for infection. Kaplan-Meier survivorship analysis revealed that the 16-year rate of survival of the components was 94.7% as the end point of loosening and 92% as the end point of revision.

  17. Arthroscopic Scar Resection for the Treatment of Anteromedial Knee Pain after Oxford Unicompartmental Knee Arthroplasty: A Case Report

    PubMed Central

    Kawaguchi, Kohei; Michishita, Kazuhiko; Manabe, Takeshi; Akasaka, Yoshiyuki; Kaminaga, Naoto

    2016-01-01

    Introduction: It has been reported that the unicompartmental knee arthroplasty has good long-term outcomes for Western and Japanese patients. Alternatively, several reports have described reoperations after unicompartmental knee arthroplasty because of post-operative knee pain and sometimes it is difficult to diagnose the cause of pain. Case Report: We treated a patient with anteromedial knee pain caused by intra-articular scar tissue that contained residual cement fragments on the anterior surface of a femoral implant following Oxford unicompartmental knee arthroplasty. After arthroscopic resection of the scar tissue and removal of the 3 mm residual cement covered with the scar tissue, the patient’s post-operative symptoms were considerably alleviated. Conclusion: This is the first report describing a case of painful intra-articular scar tissue following unicompartmental knee arthroplasty. PMID:28164064

  18. "You Might Say You're 9 Years Old but You're Actually 'B' Years Old Because You're Always Getting Older": Facilitating Young Students' Understanding of Variables

    ERIC Educational Resources Information Center

    Hunter, Jodie

    2010-01-01

    Student transition from arithmetical understandings to algebraic reasoning is recognised as an important but complex process. An essential element of the transition is the development of a rich understanding of variables. Drawing on findings from a classroom-based study, this paper outlines the instructional tasks and pedagogical actions a teacher…

  19. Enquete sur le langage de l'enfant francais: Transcriptions de conversations d'enfants de 9 ans (Investigation of the Language of French Children: Transcriptions of Conversations of 9-Year-Olds). Document No. 1.

    ERIC Educational Resources Information Center

    Leclercq, Janine, Comp.

    These transcriptions of children living in a suburb of Paris represent and illustrate linguistic behavior and interests of the average nine-year-old French child. Seventy-nine children in groups of three were recorded in 30-minute periods of free conversation and 10-minute periods of play. Analysis reveals more than 30 centers of interest which…

  20. The relationship of birthweight, muscle size at birth and post-natal growth to grip strength in 9-year-old Indian children: findings from the Mysore Parthenon study.

    PubMed

    Barr, J G; Veena, S R; Kiran, K N; Wills, A K; Winder, N R; Kehoe, S; Fall, C H D; Sayer, A A; Krishnaveni, G V

    2010-10-01

    Foetal development may permanently affect muscle function. Indian newborns have a low mean birthweight, predominantly due to low lean tissue and muscle mass. We aimed to examine the relationship of birthweight, and arm muscle area (AMA) at birth and post-natal growth to handgrip strength in Indian children. Grip strength was measured in 574 children aged 9 years, who had detailed anthropometry at birth and every 6-12 months post-natally. Mean (standard deviation (s.d.)) birthweight was 2863 (446) g. At 9 years, the children were short (mean height s.d. -0.6) and light (mean weight s.d. -1.1) compared with the World Health Organization growth reference. Mean (s.d.) grip strength was 12.7 (2.2) kg (boys) and 11.0 (2.0) kg (girls). Weight, length and AMA at birth, but not skinfold measurements at birth, were positively related to 9-year grip strength (β = 0.40 kg/s.d. increase in birthweight, P < 0.001; and β = 0.41 kg/s.d. increase in AMA, P < 0.001). Grip strength was positively related to 9-year height, body mass index and AMA and to gains in these measurements from birth to 2 years, 2-5 years and 5-9 years (P < 0.001 for all). The associations between birth size and grip strength were attenuated but remained statistically significant for AMA after adjusting for 9-year size. We conclude that larger overall size and muscle mass at birth are associated with greater muscle strength in childhood, and that this is mediated mainly through greater post-natal size. Poorer muscle development in utero is associated with reduced childhood muscle strength.

  1. Knee-Extension Training with a Single-Joint Hybrid Assistive Limb during the Early Postoperative Period after Total Knee Arthroplasty in a Patient with Osteoarthritis

    PubMed Central

    Sugaya, Hisashi; Kubota, Shigeki; Onishi, Mio; Kanamori, Akihiro; Sankai, Yoshiyuki; Yamazaki, Masashi

    2016-01-01

    The knee range of motion is an important outcome of total knee arthroplasty (TKA). According to previous studies, the knee range of motion temporarily decreases for approximately 1 month after TKA due to postoperative pain and quadriceps dysfunction following surgical invasion into the knee extensor mechanism. We describe our experience with a knee-extension training program based on a single-joint hybrid assistive limb (HAL-SJ, Cyberdyne Inc., Tsukuba, Japan) during the acute recovery phase after TKA. HAL-SJ is a wearable robot suit that facilitates the voluntary control of knee joint motion. A 76-year-old man underwent HAL-SJ-based knee-extension training, which enabled him to perform knee function training during the acute phase after TKA without causing increased pain. Thus, he regained the ability to fully extend his knee postoperatively. HAL-SJ-based knee-extension training can be used as a novel post-TKA rehabilitation modality. PMID:27774330

  2. Knee symptoms among adults at risk for accelerated knee osteoarthritis: data from the Osteoarthritis Initiative.

    PubMed

    Davis, Julie; Eaton, Charles B; Lo, Grace H; Lu, Bing; Price, Lori Lyn; McAlindon, Timothy E; Barbe, Mary F; Driban, Jeffrey B

    2017-02-10

    The purpose of this study was to examine if adults who develop accelerated knee osteoarthritis (KOA) have greater knee symptoms with certain activities than those with or without incident common KOA. We conducted a case-control study using data from baseline and the first four annual visits of the Osteoarthritis Initiative. Participants had no radiographic KOA at baseline (Kellgren-Lawrence (KL) <2). We classified 3 groups as follows: (1) accelerated KOA: > = 1 knee developed advance-stage KOA (KL = 3 or 4) within 48 months, (2) common KOA: > = 1 knee increased in radiographic severity (excluding those with accelerated KOA), and (3) no KOA: no change in radiographic severity by 48 months. We focused on individual items from the WOMAC pain/function subscales and KOOS pain/symptoms subscales. The index visit was a year before a person met the definition for accelerated, common, or no KOA. To examine group difference in knee symptoms, we used ordinal logistic regression models for each symptom. Results are reported as odds ratios (OR) and 95% confidence intervals (CI). Individuals who developed accelerated KOA were more likely to report greater difficulty with lying down (OR = 2.10, 95% CI = 1.04 to 4.25), pain with straightening the knee fully (OR = 2.04, 95% CI = 1.08, 3.85), and pain walking (OR = 2.49, 95% CI = 1.38, 4.84) than adults who developed common KOA. Individuals who develop accelerated KOA report greater symptoms with certain activities than those with common KOA. Our results may help identify individuals at risk for accelerated KOA or with early-stage accelerated KOA.

  3. Modified walking shoes for knee osteoarthritis: Mechanisms for reductions in the knee adduction moment.

    PubMed

    Kean, Crystal O; Bennell, Kim L; Wrigley, Tim V; Hinman, Rana S

    2013-08-09

    The objective of this study was to examine mechanisms underpinning the reduction in knee adduction moment (KAM) and changes in frontal plane knee-ground reaction force (GRF) lever arm with a modified shoe that incorporates both a variable-stiffness sole and lateral wedging. Thirty individuals with symptomatic knee osteoarthritis (OA) and 30 overweight asymptomatic individuals underwent gait analyses wearing modified and standard shoes. In both groups, there was a decrease in the lever arm (p<0.001), and a lateral shift in the center of pressure (COP) offset (p ≤ 0.001). There was no change in frontal plane or medial-lateral GRF magnitudes, lateral trunk lean or stance duration in either group. There was no significant change in the frontal plane hip-knee-ankle angle in the OA group but a significant decrease in the overweight group (p=0.003). In both groups, changes in lever arm and frontal plane GRF magnitude predicted change in peak KAM (p<0.01), but only change in lever arm predicted change in KAM impulse (p<0.001). In the OA group, changes in COP offset and medial-lateral GRF magnitude predicted change in lever arm (p<0.05), whereas changes in trunk lean and hip-knee-ankle angle predicted change in lever arm in the overweight group (p=0.01). In conclusion, the change in lever arm contributed the most to explaining change in KAM parameters with modified shoes. The change in the lever arm was driven by changes evident at the foot in the OA participants (COP and medial-lateral GRF), and by more proximal changes (hip-knee-ankle angle and trunk lean) in the overweight group.

  4. Knee adduction moment relates to medial femoral and tibial cartilage morphology in clinical knee osteoarthritis.

    PubMed

    Maly, Monica R; Acker, Stacey M; Totterman, Saara; Tamez-Peña, José; Stratford, Paul W; Callaghan, Jack P; Adachi, Jonathan D; Beattie, Karen A

    2015-09-18

    The objective was to determine the extent to which the external peak knee adduction moment (KAM) and cumulative knee adductor load explained variation in medial cartilage morphology of the tibia and femur in knee osteoarthritis (OA). Sixty-two adults with clinical knee OA participated (61.5 ± 6.2 years). To determine KAM, inverse dynamics was applied to motion and force data of walking. Cumulative knee adductor load reflected KAM impulse and loading frequency. Loading frequency was captured from an accelerometer. Magnetic resonance imaging scans were acquired with a coronal fat-saturated sequence using a 1.0 T peripheral scanner. Scans were segmented for medial cartilage volume, surface area of the bone-cartilage interface, and thickness. Forward linear regressions assessed the relationship of loading variables with cartilage morphology unadjusted, then adjusted for covariates. In the medial tibia, age and peak KAM explained 20.5% of variance in mean cartilage thickness (p<0.001). Peak KAM alone explained 12.3% of the 5th percentile of medial tibial cartilage thickness (i.e., thinnest cartilage region) (p=0.003). In the medial femur, sex, BMI, age, and peak KAM explained 44% of variance in mean cartilage thickness, with peak KAM contributing 7.9% (p<0.001). 20.7% of variance in the 5th percentile of medial femoral cartilage thickness was explained by BMI and peak KAM (p=0.001). In these models, older age, female sex, greater BMI, and greater peak KAM related with thinner cartilage. Models of KAM impulse produced similar results. In knee OA, KAM peak and impulse, but not loading frequency, were associated with cartilage thickness of the medial tibia and femur.

  5. Total Knee Arthroplasty After Knee Arthroscopy in Patients Older Than 50 Years.

    PubMed

    Boyd, Jason A; Gradisar, Ian M

    2016-11-01

    Several orthopedic registries have described the incidence of total knee arthroplasty (TKA) in patients who have undergone knee arthroscopy. Patient risk factors may play a role in the conversion rate from knee arthroscopy to TKA. This study quantifies the incidence of conversion of knee arthroscopy to TKA from a US mixed-payer database and describes some common patient risk factors for conversion. The medical records of more than 50 million patients who were treated between 1998 and 2014 were mined with a commercially available software platform. During the study period, a total of 68,090 patients older than 50 years underwent knee arthroscopy for partial meniscectomy, chondroplasty, or debridement. Reported rates of TKA at 1, 2, and 3 years after arthroscopy were 10.1%, 13.7%, and 15.6%, respectively. Obesity, depressive disorder, rheumatoid arthritis, diabetes, and age 70 years and older were associated with increased relative risk of conversion to TKA at 2 years. When obesity was combined individually with the top 5 other risk factors, no combination produced a higher relative risk than that of obesity alone. Patients who were 50 to 54 years of age had the lowest incidence of conversion to TKA (8.3%, P<.001). Men had a lower incidence of conversion to TKA (11.3%) than women (15.8%, P<.001). This information can help surgeons to counsel patients on the incidence of TKA after knee arthroscopy and identify preoperative risk factors that increase risk. [Orthopedics. 2016; 39(6):e1041-e1044.].

  6. Wear analysis of unicondylar mobile bearing and fixed bearing knee systems: a knee simulator study.

    PubMed

    Kretzer, J Philippe; Jakubowitz, Eike; Reinders, Jörn; Lietz, Eva; Moradi, Babak; Hofmann, Kerstin; Sonntag, Robert

    2011-02-01

    Unicondylar knee arthroplasty is an attractive alternative to total knee arthroplasty for selected patients with osteoarthritis. Mobile bearing knee designs have been developed to improve knee kinematics, lower contact stresses and reduced wear of ultra-high molecular weight polyethylene compared with fixed bearing designs. This study compared in vitro wear behavior of fixed and mobile unicondylar bearing designs. Analysis was performed using a force-controlled AMTI knee simulator according to ISO 14243-1:2002(E). The wear volume of the implants was determined gravimetrically. Optical surface characterization and an estimation of wear particle size and morphology were performed. Implant kinematic data for both designs were determined. The wear rates averaged 10.7 ± 0.59 mg per 10(6) cycles for the medial and 5.38 ± 0.63 mg per 10(6) cycles for the lateral components of the mobile bearings, compared with 7.51 ± 0.29 mg per 10(6) cycles and 3.04 ± 0.35 mg per 10(6) cycles for the fixed bearings. The mobile bearings therefore exhibited higher wear rates (P<0.01) compared with the fixed bearings. The tibial polyethylene inserts of the mobile bearings showed pronounced backside wear at the inferior surface. The kinematics of both designs was similar. However, anterior-posterior translation was lower in the mobile bearings. The wear particles were mainly elongated and small in size for both designs (P=0.462). This study shows that wear may play an important role in unicondylar mobile bearing knee designs. Advantages of unicondylar mobile designs compared with fixed bearing designs, which have been proposed in terms of wear behavior and improved kinematics, could not be confirmed.

  7. Knee kinetic pattern during gait and anterior knee pain before and after rehabilitation in patients with patellofemoral pain syndrome.

    PubMed

    Claudon, B; Poussel, M; Billon-Grumillier, C; Beyaert, C; Paysant, J

    2012-05-01

    Patellofemoral pain is likely due to compressive force acting on the patella related in turn to knee extension moment. The latter variable was assumed to be (i) reduced during short-distance free walking in case of patellofemoral pain syndrome and (ii) increased after therapeutic pain reduction. Peak knee extension moment at beginning of stance phase was recorded by three-dimensional gait analysis in 22 controls and in 23 patients with patellofemoral pain syndrome before and after rehabilitation of knee extensors and flexors to reduce the pain. Pain would occur mainly in stressful activities such as stair negotiation or squatting and was quantified by the anterior knee pain scale. Peak knee extension moment was significantly reduced in all the patients before treatment (n=23) compared to controls, although no one had pain during free walking. In the 17 patients who experienced significant post-rehabilitation pain reduction in their stressful activities, the peak knee extension moment was significantly reduced before treatment compared to controls and significantly increased after treatment, reaching values similar to control values. The peak knee extension moment during free walking appears to be a good kinetic variable related to a compensatory mechanism limiting or avoiding anterior knee pain and may be of interest in assessing knee dynamics alteration in patients with PFPS.

  8. Is latero-medial patellar mobility related to the range of motion of the knee joint after total knee arthroplasty?

    PubMed

    Ota, Susumu; Nakashima, Takeshi; Morisaka, Ayako; Omachi, Takaaki; Ida, Kunio; Kawamura, Morio

    2010-12-01

    Diminished range of motion (ROM) of the knee joint after total knee arthroplasty (TKA) is thought to be related to reduced patellar mobility. This has not been confirmed clinically due to a lack of quantitative methods adequate for measuring patellar mobility. We investigated the relationship between patellar mobility by a reported quantitative method and knee joint ROM after TKA. Forty-nine patients [osteoarthritis--OA: 29 knees; rheumatoid arthritis--RA: 20 knees] were examined after TKA. Respective medial and lateral patellar mobility was measured 1 and 6 months postoperatively using a patellofemoral arthrometer (PFA). Knee joint ROM was also measured in each of those 2 sessions. Although the flexion and extension of the knee joints improved significantly from 1 to 6 months after TKA, the medial and lateral patellar displacements (LPDs) failed to improve during that same period. Moreover, only the changes in knee flexion and medial patellar displacement (MPD) between the two sessions were positively correlated (r = 0.31, p < 0.05). However, our findings demonstrated that medial and lateral patellar mobility had no sufficient longitudinal relationship with knee ROM after TKA.

  9. Highly conforming polyethylene inlays reduce the in vivo variability of knee joint kinematics after total knee arthroplasty.

    PubMed

    Daniilidis, Kiriakos; Skwara, Adrian; Vieth, Volker; Fuchs-Winkelmann, Susanne; Heindel, Walter; Stückmann, Volker; Tibesku, Carsten O

    2012-08-01

    The use of highly conforming polyethylene inlays in total knee arthroplasty (TKA) provides improved anteroposterior stability. The aim of this fluoroscopic study was to investigate the in vivo kinematics during unloaded and loaded active extension with a highly conforming inlay and a flat inlay after cruciate retaining (CR) total knee arthroplasty (TKA). Thirty one patients (50 knees) received a fixed-bearing cruciate retaining total knee arthroplasty (Genesis II, Smith & Nephew, Schenefeld, Germany) for primary knee osteoarthritis. Twenty two of them received a flat polyethylene inlay (PE), nine a deep dished PE and 19 were in the control group (physiological knees). The mean age at the time of surgery was 62 years. Dynamic examination with fluoroscopy was performed to assess the "patella tendon angle" in relation to the knee flexion angle (measure of anteroposterior translation) and the "kinematic index" (measure of reproducibility). Fluoroscopy was performed under active extension and flexion, during unloaded movement, and under full weight bearing, simulated by step climbing. No significant difference was observed between both types of polyethylene inlay designs and the physiological knee during unloaded movement. Anteroposterior (AP) instability was found during weight-bearing movement. The deep-dish inlay resulted in lower AP translation and a non-physiological rollback. Neither inlay types could restore physiological kinematics of the knee. Despite the fact that deep dished inlays reduce the AP translation, centralisation of contact pressure results in non-physiological rollback. The influence of kinematic pattern variability on clinical results warrants further investigation.

  10. The effectiveness of posterior knee capsulotomies and knee extension osteotomies in crouched gait in children with cerebral palsy.

    PubMed

    Taylor, Daveda; Connor, Justin; Church, Chris; Lennon, Nancy; Henley, John; Niiler, Tim; Miller, Freeman

    2016-11-01

    Crouched gait is common in children with cerebral palsy (CP), and there are various treatment options. This study evaluated the effectiveness of single-event multilevel surgery including posterior knee capsulotomy or distal femoral extension osteotomy to correct knee flexion contracture in children with CP. Gait analyses were carried out to evaluate gait preoperatively and postoperatively. Significant improvements were found in physical examination and kinematic measures, which showed that children with CP and crouched gait who develop knee flexion contractures can be treated effectively using single-event multilevel surgery including a posterior knee capsulotomy or distal femoral extension osteotomy.

  11. Kinematic and dynamic analysis of an anatomically based knee joint.

    PubMed

    Lee, Kok-Meng; Guo, Jiajie

    2010-05-07

    This paper presents a knee-joint model to provide a better understanding on the interaction between natural joints and artificial mechanisms for design and control of rehabilitation exoskeletons. The anatomically based knee model relaxes several commonly made assumptions that approximate a human knee as engineering pin-joint in exoskeleton design. Based on published MRI data, we formulate the kinematics of a knee-joint and compare three mathematical approximations; one model bases on two sequential circles rolling a flat plane; and the other two are mathematically differentiable ellipses-based models with and without sliding at the contact. The ellipses-based model taking sliding contact into accounts shows that the rolling-sliding ratio of a knee-joint is not a constant but has an average value consistent with published measurements. This knee-joint kinematics leads to a physically more accurate contact-point trajectory than methods based on multiple circles or lines, and provides a basis to derive a knee-joint kinetic model upon which the effects of a planar exoskeleton mechanism on the internal joint forces and torque during flexion can be numerically investigated. Two different knee-joint kinetic models (pin-joint approximation and anatomically based model) are compared against a condition with no exoskeleton. The leg and exoskeleton form a closed kinematic chain that has a significant effect on the joint forces in the knee. Human knee is more tolerant than pin-joint in negotiating around a singularity but its internal forces increase with the exoskeleton mass-to-length ratio. An oversimplifying pin-joint approximation cannot capture the finite change in the knee forces due to the singularity effect.

  12. A multicenter analysis of axial femorotibial rotation after total knee arthroplasty.

    PubMed

    Dennis, Douglas A; Komistek, Richard D; Mahfouz, Mohamed R; Walker, Scott A; Tucker, Abby

    2004-11-01

    A multicenter analysis was done to determine in vivo femorotibial axial rotation magnitudes and patterns in 1,027 knees (normal knees, nonimplanted ACL-deficient knees, and multiple designs of total knee arthroplasty). All knees were analyzed using fluoroscopy and a three-dimensional computer model-fitting technique during a deep knee bend and/or gait. Normal knees showed 16.5 degrees and 5.7 degrees of internal tibial rotation during a deep knee bend and gait, respectively. Rotation magnitudes and the percent having normal axial rotation patterns decreased in all total knee arthroplasty groups during a deep knee bend. During gait, all knee arthroplasty groups had similar rotational patterns (limited magnitudes). Average axial rotational magnitudes in gait and a deep knee bend were similar among major implant categories (ie, fixed-bearing versus mobile-bearing, etc). Average values in normal knees and ACL-retaining total knee arthroplasty patients (16.5 degrees and 8.1 degrees , respectively) were higher than in groups in which the ACL was absent (< 4.0 degrees ). All total knee arthroplasty groups had at least 19% of patients have a reverse axial rotational pattern during a deep knee bend and at least 31% during gait. Normal axial rotation patterns are essential for good patellar tracking, reduction of patellofemoral shear forces, and maximization of knee flexion.

  13. Relationship of Buckling and Knee Injury to Pain Exacerbation in Knee Osteoarthritis: A Web-Based Case-Crossover Study

    PubMed Central

    Zobel, Isabelle; Erfani, Tahereh; Bennell, Kim L; Makovey, Joanna; Metcalf, Ben; March, Lyn; Zhang, Yuqing; Eckstein, Felix

    2016-01-01

    Background Knee osteoarthritis (OA) is one of the most frequent causes of limited mobility and diminished quality of life. Pain is the main symptom that drives individuals with knee OA to seek medical care and a recognized antecedent to disability and eventually joint replacement. Evidence shows that patients with symptomatic OA experience fluctuations in pain severity. Mechanical insults to the knee such as injury and buckling may contribute to pain exacerbation. Objective Our objective was to examine whether knee injury and buckling (giving way) are triggers for exacerbation of pain in persons with symptomatic knee OA. Methods We conducted a case-crossover study, a novel methodology in which participants with symptomatic radiographic knee OA who have had knee pain exacerbations were used as their own control (self-matched design), with all data collected via the Internet. Participants were asked to log-on to the study website and complete an online questionnaire at baseline and then at regular 10-day intervals for 3 months (control periods)—a total of 10 questionnaires. They were also instructed to go to the website and complete pain exacerbation questionnaires when they experienced an isolated incident of knee pain exacerbation (case periods). A pain exacerbation “case” period was defined as an increase of ≥2 compared to baseline. At each contact the pain exacerbation was designated a case period, and at all other regular 10-day contacts (control periods) participants were asked about knee injuries during the previous 7 days and knee buckling during the previous 2 days. The relationship of knee injury and buckling to the risk of pain exacerbation was examined using conditional logistic regression models. Results The analysis included 157 participants (66% women, mean age: 62 years, mean BMI: 29.5 kg/m2). Sustaining a knee injury was associated with experiencing a pain exacerbation (odds ratio [OR] 10.2, 95% CI 5.4, 19.3) compared with no injury. Knee

  14. Anatomic Versus Mechanically Aligned Total Knee Arthroplasty for Unicompartmental Knee Arthroplasty Revision

    PubMed Central

    Toliopoulos, Panagiota; LeBlanc, Marc-Andre; Hutt, Jonathan; Lavigne, Martin; Desmeules, Francois; Vendittoli, Pascal-Andre

    2016-01-01

    Objectives: The purpose of this study was to compare the intra-operative benefits and the clinical outcomes from kinematic or mechanical alignment for total knee arthroplasty (TKA) in patients undergoing revision of failed unicompartmental kneel arthroplasty (UKA) to TKA. Methods: Ten revisions were performed with a kinematic alignment technique and 11 with a mechanical alignment. Measurements of the hip-knee-ankle angle (HKA), the lateral distal femoral angle (LDFA), and the medial proximal tibial angle (MPTA) were performed using long-leg radiographs. The need for augments, stems, and constrained inserts was compared between groups. Clinical outcomes were compared using the WOMAC score along with maximum distance walked as well as knee range of motion obtained prior to discharge. All data was obtained by a retrospective review of patient files. Results: The kinematic group required less augments, stems, and constrained inserts than the mechanical group and thinner polyethylene bearings. There were significant differences in the lateral distal femoral angle (LDFA) and the medial proximal tibial angle (MPTA) between the two groups (p<0.05). The mean WOMAC score obtained at discharge was better in the kinematic group as was mean knee flexion. At last follow up of 34 months for the kinematic group and 58 months for the mechanical group, no orthopedic complications or reoperations were recorded. Conclusion: Although this study has a small patient cohort, our results suggest that kinematic alignment for TKA after UKA revision is an attractive method. Further studies are warranted. PMID:27563365

  15. Medial knee joint loading increases in those who respond to hyaluronan injection for medial knee osteoarthritis.

    PubMed

    Briem, Kristin; Axe, Michael J; Snyder-Mackler, Lynn

    2009-11-01

    Knee osteoarthritis (OA) is a cause of decline in function and the medial compartment is often affected. Intraarticular injection of hyaluronic acid (HA) is indicated as a symptom modifying treatment with at least 6 months passing between consecutive injection series. The effects of HA injection on gait variables have not been extensively examined. Therefore, our objective was to investigate the effects of HA injection on gait in people with medial knee OA. Twenty-seven subjects were included; each was tested prior to treatment (baseline), no later than 3 weeks following the last injection (post-HA), and again 5 months after treatment ended (follow-up). Responder criteria were defined to identify responders and non-responders. Subjects underwent 3D gait analysis, muscle activity was sampled, and co-contraction indices were calculated. Responders experienced increased peak knee adduction moments post-HA, whereas non-responders did not. Improved self-report scores were associated with increased knee adduction moments and increased medial co-contraction. Pain relief may result in higher loading onto the already vulnerable medial compartment due to changes in lower limb mechanics and muscle activation patterns. Eventually this may result in a more rapid progression of joint deterioration.

  16. Novel knee joint mechanism of transfemoral prosthesis for stair ascent.

    PubMed

    Inoue, Koh; Wada, Takahiro; Harada, Ryuchi; Tachiwana, Shinichi

    2013-06-01

    The stability of a transfemoral prosthesis when walking on flat ground has been established by recent advances in knee joint mechanisms and their control methods. It is, however, difficult for users of a transfemoral prosthesis to ascend stairs. This difficulty is mainly due to insufficient generation of extension moment around the knee joint of the prosthesis to lift the body to the next step on the staircase and prevent any unexpected flexion of the knee joint in the stance phase. Only a prosthesis with an actuator has facilitated stair ascent using a step-over-step gait (1 foot is placed per step). However, its use has issues associated with the durability, cost, maintenance, and usage environment. Therefore, the purpose of this research is to develop a novel knee joint mechanism for a prosthesis that generates an extension moment around the knee joint in the stance phase during stair ascent, without the use of any actuators. The proposed mechanism is based on the knowledge that the ground reaction force increases during the stance phase when the knee flexion occurs. Stair ascent experiments with the prosthesis showed that the proposed prosthesis can realize stair ascent without any undesirable knee flexion. In addition, the prosthesis is able to generate a positive knee joint moment power in the stance phase even without any power source.

  17. This Specialty Line of Clothing Really Is the "Bee's Knees"

    ERIC Educational Resources Information Center

    Hollingsworth, Jan Carter

    2009-01-01

    This article features "Bee's Knees," a specialty line of clothing. While not the typical product one would think of when considering mobility equipment, this line of clothing certainly does aid in helping those with disabilities access their world more safely and comfortably. "Bee's Knees" offers pint-sized pants made of kid-friendly, durable…

  18. Performance of subjects with knee osteoarthritis during walking: differential parameters.

    PubMed

    Esrafilian, Amir; Karimi, Mohammad Taghi; Amiri, Pouya; Fatoye, Francis

    2013-07-01

    The effect of knee OA on kinetic and kinematic parameters during walking and standing is still controversial. Stability and energy consumption have not been well investigated in patients with OA. This research investigated the parameters distinguishing between the healthy subjects and patients with OA performance. It also examined the differences in stability and energy consumption between patients with OA and healthy subjects. Fifteen patients with OA and fifteen healthy subjects were recruited into this study. Kinematic and kinetic assessments were performed using Qualysis motion analysis and a force plate Kistler, respectively. Stability of the subjects during walking was determined using COP. Energy consumption was calculated using the Physiological Index. Independent t test was used to determine the differences between gait, stability, and energy consumption healthy participants and patients with knee OA. The excursion of the knee, hip and pelvis in sagittal plane, excursion of the knee joint in the mediolateral plane were significantly higher (all p < 0.05) in patients with OA of the knee compared with their healthy counterparts. In addition, energy consumption was significantly higher in patients with OA (p = 0.009) than in healthy participants. However, margin of stability was significantly lower (p = 0.05) in patients with OA of the knee than in healthy subjects. These findings suggest that gait parameters and energy consumption assessments may be important in patients with OA of the knee. Therefore, clinicians are to be aware of these findings by developing appropriate gait rehabilitation for patients with OA of the knee.

  19. Medial Patellofemoral Ligament Reconstruction in a Below-Knee Amputee.

    PubMed

    El-Tawil, Sherif; Elfons Tawafig, Marian; Miles, Jonathan

    2015-01-01

    Patellar instability is a common finding in patients with below-knee amputation and yet management options are not commonly described in the literature. We describe the first reported case of a medial patellofemoral ligament reconstruction using allograft in a patient with a below-knee amputation. Clinical outcome at two-year follow-up remains very good.

  20. Medial Patellofemoral Ligament Reconstruction in a Below-Knee Amputee

    PubMed Central

    El-Tawil, Sherif; Elfons Tawafig, Marian; Miles, Jonathan

    2015-01-01

    Patellar instability is a common finding in patients with below-knee amputation and yet management options are not commonly described in the literature. We describe the first reported case of a medial patellofemoral ligament reconstruction using allograft in a patient with a below-knee amputation. Clinical outcome at two-year follow-up remains very good. PMID:26579321

  1. Relationship of bone mineral density to progression of knee osteoarthritis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective. To evaluate the longitudinal relationship between bone mineral density (BMD) and BMD changes and the progression of knee osteoarthritis (OA), as measured by cartilage outcomes. Methods. We used observational cohort data from the Vitamin D for Knee Osteoarthritis trial. Bilateral femoral ...

  2. Pathological Knee Joint Motion Analysis By High Speed Cinephotography

    NASA Astrophysics Data System (ADS)

    Baumann, Jurg U.

    1985-02-01

    The use of cinephotography for evaluation of disturbed knee joint function was compared in three groups of patients. While a sampling rate of 50 images per second was adequate for patients with neuromuscular disorders, a higher frequency of around 300 i.p.s. is necessary in osteoarthritis and ligamentous knee joint injuries, but the task of digitizing is prohibitive unless automated.

  3. The elephant knee joint: morphological and biomechanical considerations

    PubMed Central

    Weissengruber, G E; Fuss, F K; Egger, G; Stanek, G; Hittmair, K M; Forstenpointner, G

    2006-01-01

    Elephant limbs display unique morphological features which are related mainly to supporting the enormous body weight of the animal. In elephants, the knee joint plays important roles in weight bearing and locomotion, but anatomical data are sparse and lacking in functional analyses. In addition, the knee joint is affected frequently by arthrosis. Here we examined structures of the knee joint by means of standard anatomical techniques in eight African (Loxodonta africana) and three Asian elephants (Elephas maximus). Furthermore, we performed radiography in five African and two Asian elephants and magnetic resonance imaging (MRI) in one African elephant. Macerated bones of 11 individuals (four African, seven Asian elephants) were measured with a pair of callipers to give standardized measurements of the articular parts. In one Asian and three African elephants, kinematic and functional analyses were carried out using a digitizer and according to the helical axis concept. Some peculiarities of healthy and arthrotic knee joints of elephants were compared with human knees. In contrast to those of other quadruped mammals, the knee joint of elephants displays an extended resting position. The femorotibial joint of elephants shows a high grade of congruency and the menisci are extremely narrow and thin. The four-bar mechanism of the cruciate ligaments exists also in the elephant. The main motion of the knee joint is extension–flexion with a range of motion of 142°. In elephants, arthrotic alterations of the knee joint can lead to injury or loss of the cranial (anterior) cruciate ligament. PMID:16420379

  4. Associations between dietary antioxidants intake and radiographic knee osteoarthritis.

    PubMed

    Li, Hui; Zeng, Chao; Wei, Jie; Yang, Tuo; Gao, Shu-Guang; Li, Yu-Sheng; Lei, Guang-Hua

    2016-06-01

    The aim of the study is to examine the cross-sectional associations between dietary antioxidants (carotenoid, vitamin C, E, and selenium) intake and radiographic knee osteoarthritis (OA). A total of 4685 participants were included in this study. Dietary intake was assessed using a validated semi-quantitative food frequency questionnaire. Radiographic knee OA was defined as Kellgren-Lawrence (K-L) grade 2 in at least one leg. A multivariable logistic analysis model was established to test the relationship between dietary antioxidants (carotenoid, vitamin C, E, and selenium) intake and radiographic knee OA with adjustment of a number of potential confounding factors. A significant positive association between dietary vitamin C intake (P value for trend was 0.04 in multivariable adjusted analysis) and radiographic knee OA was observed. The relative odds of radiographic knee OA were increased by 0.39 times in the third quintile (OR 1.39, 95 % CI 1.11-1.73), 0.42 times in the fourth quintile (OR 1.42, 95 % CI 1.13-1.79), and 0.33 times in the fifth quintile (OR 1.33, 95 % CI 1.03-1.71). However, radiographic knee OA was not significantly associated with dietary carotenoid, vitamin E, and selenium. Among dietary antioxidants, dietary vitamin C intake was positively correlated with the prevalence of radiographic knee OA, while no significant association was found between dietary intake of carotenoid, vitamin E, and selenium and the prevalence of radiographic knee OA.

  5. Biomechanical Analysis of the Effects of Bilateral Hinged Knee Bracing.

    PubMed

    Lee, Hangil; Ha, Dokyeong; Kang, Yeoun-Seung; Park, Hyung-Soon

    2016-01-01

    This research analyzed the effect of bilateral hinged knee braces on a healthy knee from a biomechanical frame in vivo. This was accomplished by fitting a knee brace with two customized wireless force/torque (F/T) sensors that could readily record force and torque during live motion, while the kinetics at the knee were computed using the inverse dynamics of the motion capture and force plate data. Four tasks to test the brace's effects were drop vertical jumping, pivoting, stop vertical jumping, and cutting. The results showed that the hinges in the knee brace can absorb up to 18% of the force and 2.7% of the torque at the knee during various athletic motions. Thus, the hinges demonstrated minimal effect in reducing the mechanical load on the knee. There were limitations concerning the consistency of the motions performed by the subjects during the trials and the influence of the other portions of the brace to evaluate the overall effectiveness of the brace as a whole. Future works may incorporate a fatigue protocol and injured subjects to better determine the effects of the brace. There is still a need for more research on the biomechanical influence of knee braces to develop safer and more effective products.

  6. Biomechanical Analysis of the Effects of Bilateral Hinged Knee Bracing

    PubMed Central

    Lee, Hangil; Ha, Dokyeong; Kang, Yeoun-Seung; Park, Hyung-Soon

    2016-01-01

    This research analyzed the effect of bilateral hinged knee braces on a healthy knee from a biomechanical frame in vivo. This was accomplished by fitting a knee brace with two customized wireless force/torque (F/T) sensors that could readily record force and torque during live motion, while the kinetics at the knee were computed using the inverse dynamics of the motion capture and force plate data. Four tasks to test the brace’s effects were drop vertical jumping, pivoting, stop vertical jumping, and cutting. The results showed that the hinges in the knee brace can absorb up to 18% of the force and 2.7% of the torque at the knee during various athletic motions. Thus, the hinges demonstrated minimal effect in reducing the mechanical load on the knee. There were limitations concerning the consistency of the motions performed by the subjects during the trials and the influence of the other portions of the brace to evaluate the overall effectiveness of the brace as a whole. Future works may incorporate a fatigue protocol and injured subjects to better determine the effects of the brace. There is still a need for more research on the biomechanical influence of knee braces to develop safer and more effective products. PMID:27379233

  7. Review for the generalist: evaluation of anterior knee pain

    PubMed Central

    Houghton, Kristin M

    2007-01-01

    Anterior knee pain is common in children and adolescents. Evaluation and management is challenging and requires a thorough history and physical exam, and understanding of the pediatric skeleton. This article will review common causes of chronic anterior knee pain in the pediatric population with a focus on patellofemoral pain. PMID:17550634

  8. A Novel Approach to the Dissection of the Human Knee

    ERIC Educational Resources Information Center

    Clemente, F. Richard; Fabrizio, Philip A.; Shumaker, Michael

    2009-01-01

    The knee is one of the most frequently injured joints of the human body with injuries affecting the general population and the athletic population of many age groups. Dissection procedures for the knee joint typically do not allow unobstructed visualization of the anterior cruciate or posterior cruciate ligaments without sacrificing the collateral…

  9. Possibilities and limitations of novel in-vitro knee simulator.

    PubMed

    Verstraete, Matthias A; Victor, Jan

    2015-09-18

    The ex-vivo evaluation of knee kinematics remains vital to understand the impact of surgical treatments such as total knee arthroplasty (TKA). To that extent, knee simulators have been developed. However, these simulators have mainly focused on the simulation of a squatting motion. The relevance of this motion pattern for patients' activities of daily living is however questionable as squatting is difficult for elderly patients. Walking, stairs and cycling are more relevant motion patterns. This paper presents the design and control of a simulator that allows to independently control the applied kinematic and kinetic boundary conditions to simulate these daily life activities. Thereby, the knee is left with five degrees of freedom; only the knee flexion is actively controlled. From a kinetic point of view, the quadriceps and hamstring muscles are loaded. Optionally, a varus/valgus moment can be applied, facilitating a dynamic evaluation of the knee's stability. The simulator is based on three control loops, whose synchronization appears satisfactory. The input for these control loops can be determined from either musculoskeletal simulations or in accordance to literature data for traditional knee simulators. This opens the door towards an improved understanding of the knee biomechanics and comparison between different applied motion and force patterns.

  10. Relationship between foot function and medial knee joint loading in people with medial compartment knee osteoarthritis

    PubMed Central

    2013-01-01

    Background Dynamic joint loading, particularly the external knee adduction moment (KAM), is an important surrogate measure for the medio-lateral distribution of force across the knee joint in people with knee osteoarthritis (OA). Foot motion may alter the load on the medial tibiofemoral joint and hence affect the KAM. Therefore, this study aimed to investigate the relationship between tibia, rearfoot and forefoot motion in the frontal and transverse planes and the KAM in people with medial compartment knee OA. Method Motion of the knee, tibia, rearfoot and forefoot and knee moments were evaluated in 32 patients with clinically and radiographically-confirmed OA, predominantly in the medial compartment. Pearson’s correlation coefficient was used to investigate the association between peak values of tibia, rearfoot and forefoot motion in the frontal and transverse planes and 1st peak KAM, 2nd peak KAM, and the knee adduction angular impulse (KAAI). Results Lateral tilt of the tibia was significantly associated with increased 1st peak KAM (r = 0.60, p < 0.001), 2nd peak KAM (r = 0.67, p = 0.001) and KAAI (r = 0.82, p = 0.001). Increased peak rearfoot eversion was significantly correlated with decreased 2nd peak KAM (r = 0.59, p < 0.001) and KAAI (r = 0.50, p = 0.004). Decreased rearfoot internal rotation was significantly associated with increased 2nd peak KAM (r = −0.44, p = 0.01) and KAAI (r = −0.38, p = 0.02), while decreased rearfoot internal rotation relative to the tibia was significantly associated with increased 2nd peak KAM (r = 0.43, p = 0.01). Significant negative correlations were found between peak forefoot eversion relative to the rearfoot and 2nd peak KAM (r = −0.53, p = 0.002) and KAAI (r = −0.51, p = 0.003) and between peak forefoot inversion and 2nd peak KAM (r = −0.54, p = 0.001) and KAAI (r = −0.48, p = 0.005). Conclusion Increased rearfoot

  11. The relationship between knee arthroplasty and foot loading.

    PubMed

    Voronov, Michael L; Pinzur, Michael S; Havey, Robert M; Carandang, Gerard; Gil, Joseph A; Hopkinson, William J

    2012-02-01

    Surgeons have questioned whether foot deformity applies abnormal loading on a knee implant. A total of 24 patients with mild knee deformity underwent a static recording of foot loading prior to and at 3 months following knee replacement. Of these patients, 13 had a preoperative varus deformity. The recorded postoperative to preoperative loading in all 6 geographic sites was decreased by an average of 10%. The largest changes were observed in the hallux and lesser toe masks, whereas the postoperative to preoperative foot pressure ratio in the metatarsal head (lateral and medial), heel, and midfoot masks was 0.94. This preliminary investigation reveals a minimal change in geographic foot loading following total knee arthroplasty in patients with mild knee deformity.

  12. Forces and moments on the knee during kneeling and squatting.

    PubMed

    Pollard, Jonisha P; Porter, William L; Redfern, Mark S

    2011-08-01

    Euler angle decomposition and inverse dynamics were used to determine the knee angles and net forces and moments applied to the tibia during kneeling and squatting with and without kneepads for 10 subjects in four postures: squatting (Squat), kneeling on the right knee (One Knee), bilateral kneeling near full flexion (Near Full) and bilateral kneeling near 90° flexion (Near 90). Kneepads affected the knee flexion (p = .002), medial forces (p = .035), and internal rotation moments (p = .006). Squat created loading conditions that had higher varus (p < .001) and resultant moments (p = .027) than kneeling. One Knee resulted in the highest force magnitudes and net moments (p < .001) of the kneeling postures. Thigh-calf and heel-gluteus contact forces decreased the flexion moment on average by 48% during Squat and Near Full.

  13. Interpolation function for approximating knee joint behavior in human gait

    NASA Astrophysics Data System (ADS)

    Toth-Taşcǎu, Mirela; Pater, Flavius; Stoia, Dan Ioan

    2013-10-01

    Starting from the importance of analyzing the kinematic data of the lower limb in gait movement, especially the angular variation of the knee joint, the paper propose an approximation function that can be used for processing the correlation among a multitude of knee cycles. The approximation of the raw knee data was done by Lagrange polynomial interpolation on a signal acquired using Zebris Gait Analysis System. The signal used in approximation belongs to a typical subject extracted from a lot of ten investigated subjects, but the function domain of definition belongs to the entire group. The study of the knee joint kinematics plays an important role in understanding the kinematics of the gait, this articulation having the largest range of motion in whole joints, in gait. The study does not propose to find an approximation function for the adduction-abduction movement of the knee, this being considered a residual movement comparing to the flexion-extension.

  14. Evolution of the low contact stress (LCS) complete knee system.

    PubMed

    Crossett, Larry

    2006-09-01

    The low contact stress knee design was one of the first designs to become widely available and popular for total knee arthroplasty. The low contact stress knee was initially designed to address wear due to high contact stresses seen in fixed-bearing designs. Today, nearly 30 years after its introduction, the technology behind the knee remains just as relevant. Many of the original innovations in early low contact stress knee systems are still in use today. New innovations, like a new instrument set and the advent of computer-assisted surgery, have added to the success of the technology. The history of this innovative design is discussed with special consideration given to the specific design principals that have improved the basic design over the past three decades.

  15. Knee Joint Loading during Gait in Healthy Controls and Individuals with Knee Osteoarthritis

    PubMed Central

    Kumar, Deepak; Manal, Kurt T.; Rudolph, Katherine S.

    2013-01-01

    Objective People with knee osteoarthritis (OA) are thought to walk with high loads at the knee which are yet to be quantfied using modeling techniques that account for subject specific EMG patterns, kinematics and kinetics. The objective was to estimate medial and lateral loading for people with knee OA and controls using an approach that is sensitive to subject specific muscle activation patterns. Methods 16 OA and 12 control (C) subjects walked while kinematic, kinetic and EMG data were collected. Muscle forces were calculated using an EMG-Driven model and loading was calculated by balancing the external moments with internal muscle and contact forces Results OA subjects walked slower and had greater laxity, static and dynamic varus alignment, less flexion and greater knee adduction moment (KAM). Loading (normalized to body weight) was no different between the groups but OA subjects had greater absolute medial load than controls and maintained a greater %total load on the medial compartment. These patterns were associated with body mass, sagittal and frontal plane moments, static alignment and close to signficance for dynamic alignment. Lateral compartment unloading during mid-late stance was observed in 50% of OA subjects. Conclusions Loading for control subjects was similar to data from instrumented prostheses. Knee OA subjects had high medial contact loads in early stance and half of the OA cohort demonstared lateral compartment lift-off. Results suggest that interventions aimed at reducing body weight and dynamic malalignment might be effective in reducing medial compartment loading and establishing normal medio-lateral load sharing patterns. PMID:23182814

  16. Open Knee: Open Source Modeling & Simulation to Enable Scientific Discovery and Clinical Care in Knee Biomechanics

    PubMed Central

    Erdemir, Ahmet

    2016-01-01

    Virtual representations of the knee joint can provide clinicians, scientists, and engineers the tools to explore mechanical function of the knee and its tissue structures in health and disease. Modeling and simulation approaches such as finite element analysis also provide the possibility to understand the influence of surgical procedures and implants on joint stresses and tissue deformations. A large number of knee joint models are described in the biomechanics literature. However, freely accessible, customizable, and easy-to-use models are scarce. Availability of such models can accelerate clinical translation of simulations, where labor intensive reproduction of model development steps can be avoided. The interested parties can immediately utilize readily available models for scientific discovery and for clinical care. Motivated by this gap, this study aims to describe an open source and freely available finite element representation of the tibiofemoral joint, namely Open Knee, which includes detailed anatomical representation of the joint's major tissue structures, their nonlinear mechanical properties and interactions. Three use cases illustrate customization potential of the model, its predictive capacity, and its scientific and clinical utility: prediction of joint movements during passive flexion, examining the role of meniscectomy on contact mechanics and joint movements, and understanding anterior cruciate ligament mechanics. A summary of scientific and clinically directed studies conducted by other investigators are also provided. The utilization of this open source model by groups other than its developers emphasizes the premise of model sharing as an accelerator of simulation-based medicine. Finally, the imminent need to develop next generation knee models are noted. These are anticipated to incorporate individualized anatomy and tissue properties supported by specimen-specific joint mechanics data for evaluation, all acquired in vitro from varying age

  17. Hierarchical imaging of the human knee

    NASA Astrophysics Data System (ADS)

    Schulz, Georg; Götz, Christian; Deyhle, Hans; Müller-Gerbl, Magdalena; Zanette, Irene; Zdora, Marie-Christine; Khimchenko, Anna; Thalmann, Peter; Rack, Alexander; Müller, Bert

    2016-10-01

    Among the clinically relevant imaging techniques, computed tomography (CT) reaches the best spatial resolution. Sub-millimeter voxel sizes are regularly obtained. For investigations on true micrometer level lab-based μCT has become gold standard. The aim of the present study is the hierarchical investigation of a human knee post mortem using hard X-ray μCT. After the visualization of the entire knee using a clinical CT with a spatial resolution on the sub-millimeter range, a hierarchical imaging study was performed using a laboratory μCT system nanotom m. Due to the size of the whole knee the pixel length could not be reduced below 65 μm. These first two data sets were directly compared after a rigid registration using a cross-correlation algorithm. The μCT data set allowed an investigation of the trabecular structures of the bones. The further reduction of the pixel length down to 25 μm could be achieved by removing the skin and soft tissues and measuring the tibia and the femur separately. True micrometer resolution could be achieved after extracting cylinders of several millimeters diameters from the two bones. The high resolution scans revealed the mineralized cartilage zone including the tide mark line as well as individual calcified chondrocytes. The visualization of soft tissues including cartilage, was arranged by X-ray grating interferometry (XGI) at ESRF and Diamond Light Source. Whereas the high-energy measurements at ESRF allowed the simultaneous visualization of soft and hard tissues, the low-energy results from Diamond Light Source made individual chondrocytes within the cartilage visual.

  18. Multiple needle puncturing: balancing the varus knee.

    PubMed

    Bellemans, Johan

    2011-09-09

    The so-called "pie crusting" technique using multiple stab incisions is a well-established procedure for correcting tightness of the iliotibial band in the valgus knee. It is, however, not applicable for balancing the medial side in varus knees because of the risk for iatrogenic transsection of the medial collateral ligament (MCL). This article presents our experience with a safer alternative and minimally invasive technique for medial soft tissue balancing, where we make multiple punctures in the MCL using a 19-gauge needle to progressively stretch the MCL until a correct ligament balance is achieved. Our technique requires minimal to no additional soft tissue dissection and can even be performed percutaneously when necessary. This technique, therefore, does not impact the length of the skin or soft tissue incisions. We analyzed 61 cases with varus deformity that were intraoperatively treated using this technique. In 4 other cases, the technique was used as a percutaneous procedure to correct postoperative medial tightness that caused persistent pain on the medial side. The procedure was considered successful when a 2- to 4-mm mediolateral joint line opening was obtained in extension and 2 to 6 mm in flexion. In 62 cases (95%), a progressive correction of medial tightness was achieved according to the above-described criteria. Three cases were overreleased and required compensatory release of the lateral structures and use of a thicker insert. Based on these results, we consider needle puncturing an effective and safe technique for progressive correction of MCL tightness during minimally invasive total knee arthroplasty.

  19. Regional intravenous anesthesia in knee arthroscopy

    PubMed Central

    Arslan, Mahmut; Cantürk, Mehmet; Örnek, Dilşen; Gamlı, Mehmet; Pala, Yaşar; Dikmen, Bayazit; Basaran, Melekşah

    2010-01-01

    OBJECTIVE: The goal of the study was to investigate the regıonal ıntravenous anesthesıa procedure in knee arthroscopy and to evaluate the effects of adding ketamine over the anesthesia block charactery and tourniquet pain. MATERIAL/METHOD: Forty American Society of Anesthesiologists (ASA) II patients who received knee arthroscopy were enrolled. After monitoring, a peripheral IV line was inserted.The venous blood in the lower extremity was evacuated with a bandage, and the proximal cuff of the double-cuff tourniquet was inflated. The patients were randomly split into two groups. While Group P received 80 ml 0.5% prilocaine, Group PK received 0.15 mg/kg ketamine (80 ml in total) via the dorsum of the foot. We recorded onset time of the sensory block, end time of the sensory block, presence of the motor block, the time when the patient verbally reported tourniquet pain and surgical pain, duration of tourniquet tolerance, fentanyl consumption during the operation, time to first analgesic requirement, methemoglobin values at 60 minutes, operative conditions, 24-hour analgesic consumption, discharge time, and hemodynamic parameters. RESULTS: The body mass index (BMI) of the patients who required general anesthesia was significantly higher than the BMI of other patients. The onset time of the sensory block was shorter for those in Group PK, but the time to first analgesic requirement was longer. CONCLUSION: Regıonal ıntravenous anesthesıa using the doses and volumes commonly used in knee arthroscopy may be an inadequate block among patients with high BMI values. Moreover, the addition of ketamine to the local anesthetic solution may produce a partial solution by shortening the onset of sensory block and prolonging the time until the first analgesic is required. PMID:21049208

  20. Standardized Loads Acting in Knee Implants

    PubMed Central

    Bergmann, Georg; Bender, Alwina; Graichen, Friedmar; Dymke, Jörn; Rohlmann, Antonius; Trepczynski, Adam; Heller, Markus O.; Kutzner, Ines

    2014-01-01

    The loads acting in knee joints must be known for improving joint replacement, surgical procedures, physiotherapy, biomechanical computer simulations, and to advise patients with osteoarthritis or fractures about what activities to avoid. Such data would also allow verification of test standards for knee implants. This work analyzes data from 8 subjects with instrumented knee implants, which allowed measuring the contact forces and moments acting in the joint. The implants were powered inductively and the loads transmitted at radio frequency. The time courses of forces and moments during walking, stair climbing, and 6 more activities were averaged for subjects with I) average body weight and average load levels and II) high body weight and high load levels. During all investigated activities except jogging, the high force levels reached 3,372–4,218N. During slow jogging, they were up to 5,165N. The peak torque around the implant stem during walking was 10.5 Nm, which was higher than during all other activities including jogging. The transverse forces and the moments varied greatly between the subjects, especially during non-cyclic activities. The high load levels measured were mostly above those defined in the wear test ISO 14243. The loads defined in the ISO test standard should be adapted to the levels reported here. The new data will allow realistic investigations and improvements of joint replacement, surgical procedures for tendon repair, treatment of fractures, and others. Computer models of the load conditions in the lower extremities will become more realistic if the new data is used as a gold standard. However, due to the extreme individual variations of some load components, even the reported average load profiles can most likely not explain every failure of an implant or a surgical procedure. PMID:24465856