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Sample records for acl reconstruction methods

  1. Predicting success in ACL reconstruction.

    PubMed

    Shalvoy, Robert M

    2014-11-03

    Anterior Cruciate Ligament (ACL) injury and ACL reconstruction is common in the United States. However, when compared to the standards of other orthopedics procedures today, ACL reconstruction is NOT predictably successful in restoring patients to their pre-injury state. Only 60-70% of reconstructed patients resume their previous level of activity and many patients experience some degree of osteoarthritis. The reasons for such limitations of success are many. A recent renewal of interest in the many variables affecting ACL reconstruction and the understanding of the varying needs of patients with ACL injury holds promise for improving success even today as well as ultimately providing a normal knee for patients after ACL reconstruction.

  2. PRP Augmentation for ACL Reconstruction.

    PubMed

    Andriolo, Luca; Di Matteo, Berardo; Kon, Elizaveta; Filardo, Giuseppe; Venieri, Giulia; Marcacci, Maurilio

    2015-01-01

    Current research is investigating new methods to enhance tissue healing to speed up recovery time and decrease the risk of failure in Anterior Cruciate Ligament (ACL) reconstructive surgery. Biological augmentation is one of the most exploited strategies, in particular the application of Platelet Rich Plasma (PRP). Aim of the present paper is to systematically review all the preclinical and clinical papers dealing with the application of PRP as a biological enhancer during ACL reconstructive surgery. Thirty-two studies were included in the present review. The analysis of the preclinical evidence revealed that PRP was able to improve the healing potential of the tendinous graft both in terms of histological and biomechanical performance. Looking at the available clinical evidence, results were not univocal. PRP administration proved to be a safe procedure and there were some evidences that it could favor the donor site healing in case of ACL reconstruction with patellar tendon graft and positively contribute to graft maturation over time, whereas the majority of the papers did not show beneficial effects in terms of bony tunnels/graft area integration. Furthermore, PRP augmentation did not provide superior functional results at short term evaluation. PMID:26064903

  3. Evidence-Based ACL Reconstruction

    PubMed Central

    Rodriguez-Merchan, E. Carlos

    2015-01-01

    There is controversy in the literature regarding a number of topics related to anterior cruciate ligament (ACL) reconstruction. The purpose of this article is to answer the following questions: 1) Bone-patellar tendon-bone reconstruction (BPTB-R) or hamstrimg reconstruction (H-R); 2) Double bundle or single bundle; 3) Allograft or authograft; 4) Early or late reconstruction; 5) Rate of return to sports after ACL reconstruction; 6) Rate of osteoarthritis after ACL reconstruction. A Cochrane Library and PubMed (MEDLINE) search of systematic reviews and meta-analysis related to ACL reconstruction was performed. The key words were: ACL reconstruction, systematic reviews and meta-analysis. The main criteria for selection were that the articles were systematic reviews and meta-analyses focused on the aforementioned questions. Sixty-nine articles were found, but only 26 were selected and reviewed because they had a high grade (I-II) of evidence. BPTB-R was associated with better postoperative knee stability but with a higher rate of morbidity. However, the results of both procedures in terms of functional outcome in the long-term were similar. The double-bundle ACL reconstruction technique showed better outcomes in rotational laxity, although functional recovery was similar between single-bundle and double-bundle. Autograft yielded better results than allograft. There was no difference between early and delayed reconstruction. 82% of patients were able to return to some kind of sport participation. 28% of patients presented radiological signs of osteoarthritis with a follow-up of minimum 10 years. PMID:25692162

  4. Evidence-Based ACL Reconstruction.

    PubMed

    Rodriguez-Merchan, E Carlos

    2015-01-01

    There is controversy in the literature regarding a number of topics related to anterior cruciate ligament (ACL) reconstruction. The purpose of this article is to answer the following questions: 1) Bone-patellar tendon-bone reconstruction (BPTB-R) or hamstrimg reconstruction (H-R); 2) Double bundle or single bundle; 3) Allograft or authograft; 4) Early or late reconstruction; 5) Rate of return to sports after ACL reconstruction; 6) Rate of osteoarthritis after ACL reconstruction. A Cochrane Library and PubMed (MEDLINE) search of systematic reviews and meta-analysis related to ACL reconstruction was performed. The key words were: ACL reconstruction, systematic reviews and meta-analysis. The main criteria for selection were that the articles were systematic reviews and meta-analyses focused on the aforementioned questions. Sixty-nine articles were found, but only 26 were selected and reviewed because they had a high grade (I-II) of evidence. BPTB-R was associated with better postoperative knee stability but with a higher rate of morbidity. However, the results of both procedures in terms of functional outcome in the long-term were similar. The double-bundle ACL reconstruction technique showed better outcomes in rotational laxity, although functional recovery was similar between single-bundle and double-bundle. Autograft yielded better results than allograft. There was no difference between early and delayed reconstruction. 82% of patients were able to return to some kind of sport participation. 28% of patients presented radiological signs of osteoarthritis with a follow-up of minimum 10 years. PMID:25692162

  5. Graft Diameter matters in Hamstring ACL reconstruction

    PubMed Central

    Clatworthy, Mark

    2016-01-01

    Objective: Recently techniques have been developed to increase graft diameter in hamstring ACL reconstruction with the hope to decrease graft failure. To date there is limited evidence to show that a smaller graft diameter results in a higher ACL failure rate. Method: The factors for failure in 1480 consecutive single surgeon hamstring ACL reconstructions were evaluated prospectively. Patients were followed for 2-15 years. A multivariate analysis was performed which looked at graft size, age, sex, time to surgery, meniscal integrity, meniscal repair and ACL graft placement to determine whether graft diameter matters in determining the failure of hamstring ACL reconstruction. Results: Graft diameters ranged from 6-10 mm. The mean graft diameter for all patients was 7.75 mm. 83 ACL reconstructions failed. The mean size of graft failures was 7.55 mm ACL reconstructions that failed had a significantly smaller hamstring graft diameter p=0.001. The Hazard Ratio for a smaller diameter graft is 0.517 p=<0.0001. For every 1 mm decrease in graft diameter there is a 48.3% higher chance of failure. The multivariate analysis showed a hazard ratio of 0.543 p=0.002. For every 1 mm decrease in graft diameter there is a 45.7% higher chance of failure. Conclusion: Smaller diameter hamstring grafts do have a higher failure rate. Grafts ≤ 7.5 mm had twice the failure rate of grafts ≥8 mm using a multivariate analysis for every 1 mm decrease in graft diameter there is a 45.7% higher chance of failure.

  6. NFL Combine Athletic Performance after ACL Reconstruction

    PubMed Central

    Marshall, Nathan E.; Keller, Robert A.; Mehran, Nima; Austin, William; Moutzouros, Vasilios

    2016-01-01

    Objectives: The purpose of this study was to determine the functional performance of NFL combine participants after ACL reconstruction compared with an age-, size-, and position-matched control group. The hypothesis was that there would be no difference between players after ACL reconstruction as compared with controls in functional athletic performance. Methods: A total of 98 NFL-caliber athletes who had undergone primary ACL reconstruction and participated in the NFL scouting combine between 2010 and 2014 were reviewed and compared with an age-, size-, and position-matched control group. Data recorded for each player included a 40-yard dash, vertical leap, broad jump, shuttle drill, and 3-cone drill. Results: With regard to speed and acceleration, the mean 40-yard dash time for ACL-reconstructed players was 4.74 seconds (range, 4.33-5.55 seconds) compared with controls at 4.74 seconds (range, 4.34-5.38 seconds; P = .96). Jumping performance was also similar, with a mean vertical leap for ACL-reconstructed players of 33.35 inches (range, 23-43 inches) and broad jump of 113.9 inches (range, 96-136 inches) compared with respective values for the controls of 33.22 inches (range, 23.5-43.5 inches; P = .84) and 113.9 inches (range, 92-134 inches; P = .99). Agility and quickness testing measures also did not show a statistically significantly difference, with ACL-reconstructed players performing the shuttle drill in 4.37 seconds (range, 4.02-4.84 seconds) and the 3-cone drill in 7.16 seconds (range, 6.45-8.14 seconds), respectively, compared with respective times for the controls of 4.37 seconds (range, 3.96-5.00 seconds; P = .91) and 7.18 seconds (range, 6.64-8.24 seconds; P = .75). Conclusion: This study suggests that after ACL reconstruction, high-caliber athletes can achieve equivalent levels of perfor- mance with no statistically significant differences compared with matched controls. This information is unique when advising high-level athletes on athletic

  7. ACL reconstruction: patellar tendon versus hamstring grafts--economical aspects.

    PubMed

    Forssblad, Magnus; Valentin, Anders; Engström, Björn; Werner, Suzanne

    2006-06-01

    The aim of the present investigation was to compare the costs for the use of patellar tendon versus hamstring tendons as grafts for anterior cruciate ligament (ACL) reconstruction including the different fixation methods. The background is that during recent years there has been a dramatic shift from patellar tendon to hamstring tendons in ACL reconstructions in Sweden. All our patients with ACL reconstructions performed during 1 year (2004) were included. Knee joints numbering 440 in 439 patients were primary ACL reconstructions. A hamstring graft was used in 345 knee joints (78.4%) and a patellar tendon graft in 95 (21.6%) of the patients (Table 2). On average 34 (SD 12.9; range 14-63) ACL reconstructions per surgeon were performed by a total of 14 surgeons. The average cost for patellar tendon procedure was 197 euros compared to 436 euros for the hamstring procedure. Mean time for surgery in primary reconstructions was 11.5 min shorter (P<0.001) for patellar tendon reconstructions (71.3+/-31 min) compared to hamstring reconstructions (83.2+/-27 min). This means a difference in cost of 90 euros. The total additional cost (fixation and surgery time) for the hamstring method compared to the patellar tendon method was on an average 329 euros. From a strict economic point of view we therefore recommend or at least consider the use of the patellar tendon as a graft in ACL reconstructions. PMID:16570193

  8. Maximizing quadriceps strength after ACL reconstruction.

    PubMed

    Palmieri-Smith, Riann M; Thomas, Abbey C; Wojtys, Edward M

    2008-07-01

    The primary objectives of ACL surgery and rehabilitation are to restore knee function to preinjury levels and promote long-term joint health. Often these goals are not achieved, however. The quadriceps is critical to dynamic joint stability, and weakness of this muscle group is related to poor functional outcomes. Because of this, identifying strategies to minimize quadriceps weakness following ACL injury and reconstruction is of great clinical interest. This article reviews the current literature and critically discusses current rehabilitation approaches to restore quadriceps muscle function after ACL reconstruction.

  9. Transphyseal ACL Reconstruction in Skeletally Immature Patients

    PubMed Central

    Cruz, Aristides I.; Lakomkin, Nikita; Fabricant, Peter D.; Lawrence, J. Todd R.

    2016-01-01

    Background: Most studies examining the safety and efficacy of transphyseal anterior cruciate ligament (ACL) reconstruction for skeletally immature patients utilize transtibial drilling. Independent femoral tunnel drilling may impart a different pattern of distal femoral physeal involvement. Purpose: To radiographically assess differences in distal femoral physeal disruption between transtibial and independent femoral tunnel drilling. We hypothesized that more oblique tunnels associated with independent drilling involve a significantly larger area of physeal disruption compared with vertically oriented tunnels. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We analyzed skeletally immature patients aged between 10 and 15 years who underwent transphyseal ACL reconstruction utilizing an independent femoral tunnel drilling technique between January 1, 2008, and March 31, 2011. These patients were matched with a transtibial technique cohort based on age and sex. Radiographic measurements were recorded from preoperative magnetic resonance imaging and postoperative radiographs. Results: Ten patients in each group were analyzed. There were significant differences between independent drilling and transtibial drilling cohorts in the estimated area of physeal disruption (1.64 vs 0.74 cm2; P < .001), femoral tunnel angles (32.1° vs 72.8°; P < .001), and medial/lateral location of the femoral tunnel (24.2 vs 36.1 mm from lateral cortex; P = .001), respectively. There was a significant inverse correlation between femoral tunnel angle and estimated area of distal femoral physeal disruption (r = –0.8255, P = .003). Conclusion: Femoral tunnels created with an independent tunnel drilling technique disrupt a larger area of the distal femoral physis and create more eccentric tunnels compared with a transtibial technique. Clinical Relevance: As most studies noting the safety of transphyseal ACL reconstruction have utilized a central, vertical femoral tunnel

  10. Abnormal landing strategies after ACL reconstruction.

    PubMed

    Gokeler, A; Hof, A L; Arnold, M P; Dijkstra, P U; Postema, K; Otten, E

    2010-02-01

    The objective was to analyze muscle activity and movement patterns during landing of a single leg hop for distance after anterior cruciate ligament (ACL) reconstruction. Nine (six males, three females) ACL-reconstructed patients 6 months after surgery and 11 (eight males, three females) healthy control subjects performed the hop task. Electromyographic signals from lower limb muscles were analyzed to determine onset time before landing. Biomechanical data were collected using an Optotrak Motion Analysis System and force plate. Matlab was used to calculate kinetics and joint kinematics. Side-to-side differences in ACL-reconstructed patients and healthy subjects as well as differences between the patients and control group were analyzed. In ACL-reconstructed limbs, significantly earlier onset times were found for all muscles, except vastus medialis, compared with the uninvolved side. The involved limbs had significantly reduced knee flexion during the take-off and increased plantarflexion at initial contact. The knee extension moment was significantly lower in the involved limb. In the control group, significantly earlier onset times were found for the semitendinosus, vastus lateralis and medial gastrocnemius of the non-dominant side compared with the dominant side. Muscle onset times are earlier and movement patterns are altered in the involved limb 6 months after ACL reconstruction.

  11. Stability Outcomes following Computer-Assisted ACL Reconstruction

    PubMed Central

    Christino, Melissa A.; Vopat, Bryan G.; Matson, Andrew P.; Reinert, Steven E.; Shalvoy, Robert M.

    2015-01-01

    Purpose. The purpose of this study was to determine whether intraoperative prereconstruction stability measurements and/or patient characteristics were associated with final knee stability after computer-assisted ACL reconstruction. Methods. This was a retrospective review of all patients who underwent computer-assisted single-bundle ACL reconstruction by a single surgeon. Prereconstruction intraoperative stability measurements were correlated with patient characteristics and postreconstruction stability measurements. 143 patients were included (87 male and 56 female). Average age was 29.8 years (SD ± 11.8). Results. Females were found to have significantly more pre- and postreconstruction internal rotation than males (P < 0.001 and P = 0.001, resp.). Patients with additional intra-articular injuries demonstrated more prereconstruction anterior instability than patients with isolated ACL tears (P < 0.001). After reconstruction, these patients also had higher residual anterior translation (P = 0.01). Among all patients with ACL reconstructions, the percent of correction of anterior translation was found to be significantly higher than the percent of correction for internal or external rotation (P < 0.001). Conclusion. Anterior translation was corrected the most using a single-bundle ACL reconstruction. Females had higher pre- and postoperative internal rotation. Patients with additional injuries had greater original anterior translation and less operative correction of anterior translation compared to patients with isolated ACL tears. PMID:25883804

  12. PROPRIOCEPTION, BODY BALANCE AND FUNCTIONALITY IN INDIVIDUALS WITH ACL RECONSTRUCTION

    PubMed Central

    Furlanetto, Tássia Silveira; Peyré-Tartaruga, Leonardo Alexandre; do Pinho, Alexandre Severo; Bernardes, Emanuele da Silva; Zaro, Milton Antonio

    2016-01-01

    Objective : To evaluate and compare proprioception, body balance and knee functionality of individuals with or without unilateral anterior cruciate ligament (ACL) reconstruction. Methods : Forty individuals were divided in two groups: Experimental group, 20 individuals with ACL reconstruction at six months postoperative, and control group, 20 individuals with no history of lower limb pathologies. In the experimental group, we assessed lower limbs with reconstructed ACL and contralateral limb; in the control group the dominant and the non-dominant lower limbs were assessed. All subjects were submitted to joint position sense test to evaluate proprioception, postural control measure in single-limb, and step up and down (SUD) test for functional assessment. Results : There were no deficits in proprioception and postural control. In the SUD test, a 5% decrease in lift up force was found in reconstructed ACL lower limbs, however, a statistically not significant difference. The impact and step down force during the course of test were 30% greater in anatomic ACL than in control lower limbs. Conclusion : The individuals with ACL reconstruction at six months postoperative did not show changes in proprioception and postural control, but showed motor control changes, influencing knee functionality. Level of Evidence IV, Prognostic Studies. PMID:26981038

  13. Femoral tunnel malposition in ACL revision reconstruction.

    PubMed

    Morgan, Joseph A; Dahm, Diane; Levy, Bruce; Stuart, Michael J

    2012-11-01

    The Multicenter Anterior Cruciate Ligament (ACL) Revision Study (MARS) group was formed to study a large cohort of revision ACL reconstruction patients. The purpose of this subset analysis study of the MARS database is to describe specific details of femoral tunnel malposition and subsequent management strategies that surgeons chose in the revision setting. The design of this study is a case series. The multicenter MARS database is compiled from a questionnaire regarding 460 ACL reconstruction revision cases returned by 87 surgeons. This subset analysis described technical aspects and operative findings in specifically those cases in which femoral tunnel malposition was cited as the cause of primary ACL reconstruction failure. Of the 460 revisions included for study, 276 (60%) cases cited a specific "technical cause of failure." Femoral tunnel malposition was cited in 219 (47.6%) of 460 cases. Femoral tunnel malposition was cited as the only cause of failure in 117 cases (25.4%). Surgeons judged the femoral tunnel too vertical in 42 cases (35.9%), too anterior in 35 cases (29.9%), and too vertical and anterior in 31 cases (26.5%). Revision reconstruction involved the drilling of an entirely new femoral tunnel in 91 cases (82.1%). For primary reconstruction, autograft tissue was used in 82 cases (70.1%). For revision reconstruction, autograft tissue was used in 61 cases (52.1%) and allograft tissue in 56 cases (47.9%). Femoral tunnel malposition in primary ACL reconstruction was the most commonly cited reason for graft failure in this cohort. Graft selection is widely variable among surgeons.

  14. Femoral Tunnel Malposition in ACL Revision Reconstruction

    PubMed Central

    Morgan, Joseph A.; Dahm, Diane; Levy, Bruce; Stuart, Michael J.

    2013-01-01

    The Multicenter Anterior Cruciate Ligament (ACL) Revision Study (MARS) group was formed to study a large cohort of revision ACL reconstruction patients. The purpose of this subset analysis study of the MARS database is to describe specific details of femoral tunnel malposition and subsequent management strategies that surgeons chose in the revision setting. The design of this study is a case series. The multicenter MARS database is compiled from a questionnaire regarding 460 ACL reconstruction revision cases returned by 87 surgeons. This subset analysis described technical aspects and operative findings in specifically those cases in which femoral tunnel malposition was cited as the cause of primary ACL reconstruction failure. Of the 460 revisions included for study, 276 (60%) cases cited a specific “technical cause of failure.” Femoral tunnel malposition was cited in 219 (47.6%) of 460 cases. Femoral tunnel malposition was cited as the only cause of failure in 117 cases (25.4%). Surgeons judged the femoral tunnel too vertical in 42 cases (35.9%), too anterior in 35 cases (29.9%), and too vertical and anterior in 31 cases (26.5%). Revision reconstruction involved the drilling of an entirely new femoral tunnel in 91 cases (82.1%). For primary reconstruction, autograft tissue was used in 82 cases (70.1%). For revision reconstruction, autograft tissue was used in 61 cases (52.1%) and allograft tissue in 56 cases (47.9%). Femoral tunnel malposition in primary ACL reconstruction was the most commonly cited reason for graft failure in this cohort. Graft selection is widely variable among surgeons. PMID:23150344

  15. Update on rehabilitation following ACL reconstruction

    PubMed Central

    Nyland, John; Brand, Emily; Fisher, Brent

    2010-01-01

    As anterior cruciate ligament (ACL) reconstruction has evolved to less invasive, more anatomical approaches, rehabilitation of the injured athlete has likewise become more progressive and innovative, with a sound understanding of graft and fixation strength and biologic healing-remodeling constraints. This review discusses these innovations including specific considerations before surgery, when planning rehabilitation timetables, and the importance of reestablishing nonimpaired active and passive knee range of motion and biarticular musculotendinous extensibility in positions of function. Concepts of self-efficacy or confidence and reestablishing the “athlete role” are also addressed. Since ACL injury and reinjury are largely related to the influence of structure-form-function on dynamic knee joint stability, the interrelationships between sensorimotor, neuromuscular, and conventional resistance training are also discussed. Although pivot shift “giving way” relates to function loss following ACL injury, anterior translational laxity often does not. Although there is growing evidence that progressive eccentric training may benefit the patient following ACL reconstruction, there is less evidence supporting the use of functional ACL knee braces. Of considerable importance is selecting and achieving a criteria-based progression to sports-specific training, reestablishing osseous homeostasis and improved bone density, blending open and closed kinetic chain exercises at the appropriate time period, and appreciating the influence of the trunk, upper extremities, and sports equipment use on knee loads. We believe that knee dysfunction and functional recovery should be considered from a local, regional, and global perspective. These concepts are consolidated into our approach to prepare patients for return to play including field testing and maintenance training. PMID:24198553

  16. Risk Factors and Predictors Of Subsequent ACL Injury After ACL Reconstruction: Prospective Analysis Of 2801 Primary ACL Reconstructions

    PubMed Central

    Kaeding, Christopher C.; Pedroza, Angela; Reinke, Emily; Huston, Laura J.; Spindler, Kurt P.

    2014-01-01

    Objectives: Retear of an ACL after an ACL reconstruction (ACLR) is devastating for all involved. Understanding risk factors and predictors of subsequent ACL tear after an ACLR is vital for patient education of subsequent risk of injury and if a predictor is modifiable, to make adjustments to minimize the risk of repeat ACL tear. The objectives of this study were 1) to identify the risk factors and predictors for ispilateral and contralateral ACL tears after primary ACLR and 2) to compare retear risk between the 2002/03 and 2007/08 cohorts. This is the largest and most comprehensive prospective analysis of this kind in the literature. Methods: Data from the 2002-2008 MOON database was used to identify risk factors for ACL retear. Subjects who had a primary ACLR with no history of contralateral knee surgery and had 2 year follow-up data were included. Subjects who had multiligament surgery were excluded. Graft type (auto-BTB, auto-hamstring, allograft), age, Marx score at time of index surgery, sport played post ACLR, sex, smoking status, lateral meniscus tear at the time of ACLR, medial meniscus tear at the time of ACLR, BMI, and MOON site were evaluated to determine their contribution to both ipsilateral retear and contralateral ACL tear. The analysis was repeated using the 2002/3 and 2007/8 cohort and included age, graft, sex, and Marx. An ANOVA with post-hoc analysis was performed to detect significant differences in age and Marx score by graft type over time. Results: A total of 2801 subjects met all inclusion/exclusion criteria. There were 165/2801 (5.89%) ipsilateral and 177/2801 (6.32%) contralateral ACL tears identified in the cohort at the two year follow-up. The odds of ipsilateral retear are 1.68 times greater for hamstring autograft (p=0.04) and 4.67 times greater for an allograft (p<0.001) compared to auto-BTB. The odds of ipsilateral retear decrease by 8% for every yearly increase in age (p < 0.001) and increases by 6% for every increased point on the

  17. ACL reconstruction in children: a transphyseal technique.

    PubMed

    Lemaitre, G; Salle de Chou, E; Pineau, V; Rochcongar, G; Delforge, S; Bronfen, C; Haumont, T; Hulet, C

    2014-06-01

    The annual incidence of ACL tears is increasing steadily in pediatric patients. Chronic anterior instability causes meniscal lesions at a frequency that increases significantly with the injury-to-surgery interval. Conservative therapy, simple suturing, and isolated extra-articular tendon reconstruction are associated with high failure rates. Intra-articular arthroscopy-assisted tendon reconstruction is a good treatment method, although several different techniques have been described. We used a transphyseal technique with a hamstring tendon graft to treat 14 knees in 13 patients with a mean age of 13 years and 7 months. Mean injury-to-surgery interval was 6 months. Strict compliance with technical rules is required when using this technique. Bone tunnel diameter must not exceed 8 mm. Bone tunnels must be as vertical and central as possible. The fixation material must not bridge the physis (at the femur, cortical fixation; and at the tibia, fixation using a resorbable screw no longer than 25 mm combined with a staple). Meniscal lesions were present in half the knees and meniscal preservation considered mandatory. Conservative treatment of concomitant lesions was performed routinely. After a mean follow-up of 15 months, no recurrent tears or revision procedures for meniscectomy had been recorded. The IKDC grade was A or B in 93% of knees. The mean subjective IKDC score was 83.3 and the Lysholm score was in the excellent or good range in 93% of knees. Of the 14 knees, 2 exhibited signs suggesting femoral epiphysiodesis, with 4° of valgus deformity compared to the contra-lateral knee and no clinical consequences. Transphyseal reconstruction with open physes conducted in strict compliance with technical rules can be performed to control the instability and preserve the menisci. Nevertheless, this technique carries a risk of epiphysiodesis, chiefly at the femur.

  18. ACL Reconstruction With Autografts Weighing Performance Considerations and Postoperative Care.

    PubMed

    Grant, John A; Mohtadi, Nicholas G

    2003-04-01

    Anterior cruciate ligament (ACL) reconstruction is the treatment of choice for patients who experience episodes of instability and a decreased quality of life after ACL rupture. The bone-patellar tendon-bone and hamstring autografts are the current standards for ACL reconstruction. Primary care physicians, especially sports medicine clinicians, are the first-line providers of nonoperative care for patients who have ACL injuries. Care providers need to know the biologic and biomechanic properties of these grafts, clinical indications for each graft, and rehabilitation considerations to appropriately counsel their patients. PMID:20086463

  19. Incidence of Second ACL Injuries 2 Years After Primary ACL Reconstruction and Return to Sport

    PubMed Central

    Paterno, Mark V.; Rauh, Mitchell J.; Schmitt, Laura C.; Ford, Kevin R.; Hewett, Timothy E.

    2014-01-01

    Background The incidence of second anterior cruciate ligament (ACL) injuries in the first 12 months after ACL reconstruction (ACLR) and return to sport (RTS) in a young, active population has been reported to be 15 times greater than that in a previously uninjured cohort. There are no reported estimates of whether this high relative rate of injury continues beyond the first year after RTS and ACLR. Hypothesis The incidence rate of a subsequent ACL injury in the 2 years after ACLR and RTS would be less than the incidence rate reported within the first 12 months after RTS but greater than the ACL injury incidence rate in an uninjured cohort of young athletes. Study Design Cohort study; Level of evidence, 2. Methods Seventy-eight patients (mean age, 17.1 ± 3.1 years) who underwent ACLR and were ready to return to a pivoting/ cutting sport and 47 controls (mean age, 17.2 ± 2.6 years) who also participated in pivoting/cutting sports were prospectively enrolled. Each participant was followed for injury and athlete exposure (AE) data for a 24-month period after RTS. Twenty-three ACLR and 4 control participants suffered an ACL injury during this time. Incidence rate ratios (IRRs) were calculated to compare the rates (per 1000 AEs) of ACL injury in athletes in the ACLR and control groups. For the ACLR group, similar comparisons were conducted for side of injury by sex. Results The overall incidence rate of a second ACL injury within 24 months after ACLR and RTS (1.39/1000 AEs) was nearly 6 times greater (IRR, 5.71; 95% CI, 2.0–22.7; P = .0003) than that in healthy control participants (0.24/1000 AEs). The rate of injury within 24 months of RTS for female athletes in the ACLR group was almost 5 times greater (IRR, 4.51; 95% CI, 1.5–18.2; P = .0004) than that for female controls. Although only a trend was observed, female patients within the ACLR group were twice as likely (IRR, 2.43; 95% CI, 0.8–8.6) to suffer a contralateral injury (1.13/1000 AEs) than an

  20. Risk Factors and Predictors of Subsequent ACL Injury in either Knee after ACL Reconstruction: Prospective Analysis of 2488 Primary ACL Reconstructions from the MOON Cohort

    PubMed Central

    Kaeding, Christopher C.; Pedroza, Angela D.; Reinke, Emily K.; Huston, Laura J.; Spindler, Kurt P.

    2015-01-01

    Background Anterior cruciate ligament (ACL) re-injury results in worse outcomes and increases risk of post-traumatic osteoarthritis. Objectives To identify the risk factors for both ipsilateral and contralateral ACL tears after primary ACL reconstruction (ACLR). Study Design Cohort study; Level of evidence, 3. Methods Data from the Multicenter Orthopaedic Outcomes Network (MOON), a prospective longitudinal cohort, were used to identify risk factors for ACL retear. Subjects with primary ACLR, no history of contralateral knee surgery, and a minimum of 2-year follow-up data were included. Age, sex, Marx activity score, graft type, lateral meniscus tear, medial meniscus tear, sport played at index injury, and surgical facility were evaluated to determine their contribution to both ipsilateral retear and contralateral ACL tear. Results A total of 2683 subjects with average age of 27 ± 11 years (1498 men; 56%) met all study inclusion/exclusion criteria. Overall there were 4.4% ipsilateral graft tears and 3.5% contralateral ACL tears. The odds of ipsilateral retear were 5.2 times greater for an allograft (p<0.01) compared with a bone-patellar tendon-bone (BTB) autograft; the odds of retear were not significantly different between BTB autograft and hamstring autograft (p=0.12). The odds of an ipsilateral ACL retear decreased by 0.09 for every yearly increase in age (p<0.01) and increased by 0.11 for every increased point on the Marx score (p< 0.01). The odds were not significantly influenced by sex, smoking status, sport played, medial or lateral meniscus tear, or consortium site (p>0.05). The odds of a contralateral ACL tear decreased by 0.04 for every yearly increase in age (p=0.04) and increased by 0.12 for every increased point on the Marx score (p<0.01); these odds were not significantly different between sex, smoking status, sport played, graft type, medial meniscal tear, and lateral meniscal tear (p>0.05). Conclusions Younger age, higher activity level, and

  1. Rehabilitation Predictors of Clinical Outcome following Revision ACL Reconstruction

    PubMed Central

    Wright, Rick W.; Group, Mars

    2016-01-01

    Objectives: Revision ACL reconstruction has been documented to have worse outcomes compared with primary ACL reconstructions. The reasons why remain unknown. The purpose of this study was to determine whether rehabilitation-related factors prescribed at the time of ACL revision reconstruction significantly influence two year outcomes, as well as the incidence of incurring a subsequent re-operation. Our hypothesis was that immediate versus passive, active range of motion (ROM) and weightbearing will result in improved outcomes without incidence of subsequent surgery. Use of postoperative and functional return to sport braces will not improve return to sports function. Methods: Revision ACL reconstruction patients were identified and prospectively enrolled between 2006 and 2011. Data collected included baseline demographics, surgical technique and pathology, prescribed post-op and rehabilitation instructions (ie. timing of weightbearing, timing of passive and active ROM, use of postoperative and return to sport braces) and a series of validated patient reported outcome instruments (IKDC, KOOS, and Marx activity rating score). Patients were followed up for 2 years, and asked to complete the identical set of outcome instruments. Because meniscal repair, meniscal transplants, HTOs, concurrent ligamentous reconstructions, and certain chondral treatments (ie. microfracture, abrasion arthroplasty, mosiacplasty, etc) are known to affect prescribed rehab treatments, patients with these pathologies were excluded from the analyses. Regression analysis was used to control for age, gender, activity level, baseline outcome scores, and the above-mentioned rehabilitation-related variables, in order to assess the risk factors for clinical outcomes 2 years after revision ACL reconstruction. Results: A total of 843 patients met the inclusion criteria and were successfully enrolled. 482 (57%) were males, with a median cohort age of 27 years. Baseline characteristics of the cohort are

  2. Increased Platelet Concentration does not Improve Functional Graft Healing in Bio-Enhanced ACL Reconstruction

    PubMed Central

    Fleming, Braden C.; Proffen, Benedikt L.; Vavken, Patrick; Shalvoy, Matthew R.; Machan, Jason T.; Murray, Martha M.

    2014-01-01

    Purpose The use of an extra-cellular matrix scaffold (ECM) combined with platelets to enhance healing of an ACL graft (“bio-enhanced ACL reconstruction”) has shown promise in animal models. However, the effects of platelet concentration on graft healing remains unknown. The objectives of this study were to determine if increasing the platelet concentration in the ECM scaffold would; 1) improve the graft biomechanical properties, and 2) decrease cartilage damage after surgery. Methods Fifty-five adolescent minipigs were randomized to 5 treatment groups; untreated ACL transection (n=10), conventional ACL reconstruction (n=15), and bio-enhanced ACL reconstruction using 1X (n=10), 3X (n=10) or 5X (n=10) platelet-rich plasma. The graft biomechanical properties, anteroposterior (AP) knee laxity, graft histology and macroscopic cartilage integrity were measured at 15 weeks. Results The mean linear stiffness of the bio-enhanced ACL reconstruction procedure using the 1X preparation was significantly greater than traditional reconstruction while the 3X and 5X preparations were not. The failure loads of all the ACL reconstructed groups were equivalent but significantly greater than untreated ACL transection. There were no significant differences in the ligament maturity index or AP laxity between reconstructed knees. Macroscopic cartilage damage was relatively minor, though significantly less when the ECM-platelet composite was used. Conclusions Only the 1X platelet concentration improved healing over traditional ACL reconstruction. Increasing the platelet concentration from 1X to 5X in the ECM scaffold did not further improve the graft mechanical properties. The use of an ECM-platelet composite decreased the amount of cartilage damage seen after ACL surgery. PMID:24633008

  3. Cross-exercise on quadriceps deficit after ACL reconstruction.

    PubMed

    Papandreou, Maria; Billis, Evdokia; Papathanasiou, George; Spyropoulos, Panagiotis; Papaioannou, Nikos

    2013-02-01

    A few studies concerning the improvement of quadriceps muscle strength deficit (QD) at an early stage following anterior cruciate ligament (ACL) reconstruction have been conducted whereas, ACL rehabilitation protocols based on contralateral quadriceps strength (QS) do not exist. Given these, the goals of our study were (1) to evaluate the effects of cross-eccentric exercise (CEE) on QD on ACL reconstructed knees, and (2) to explore any changes in QD following CEE provided at the frequencies of 3 or 5 times per week. For this study, 42 ACL-reconstructed patients were randomly assigned into 3 groups, two experimental and one control and followed an 8-week rehabilitation program. Additionally, the experimental groups received CEE for 3 and 5 days per week for 8 weeks in their uninjured knees. QS was evaluated with an isokinetic/isometric test, at 60 degrees of knee flexion of both limbs before and after completion of CEE. Two-factor ANOVA showed a significant improvement of QD between groups (F = 5.16, p = 0.01) after CEE completion on ACL reconstructed knees. Statistically significant results arose from the 3 days per week (D = 18.60, p = 0.01) and 5 days per week (D = 15.12, p = 0.04) experimental groups, whereas the control group did not yield any statistically significant differences. CEE used as an adjunct to the ACL traditional rehabilitation program at the weekly frequencies of 3 and 5 times at the early stage of reconstruction significantly improved QD.

  4. 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.

  5. Physeal Disruption During ACL Reconstruction in Skeletally Immature Patients

    PubMed Central

    Cruz, Aristides Ignacio; Lakomkin, Nikita; Fabricant, Peter D.; Lawrence, John Todd R.

    2016-01-01

    Objectives: The purpose of this study was to radiographically assess differences in distal femoral physeal disruption between transtibial and independent femoral tunnel drilling techniques following ACL reconstruction in skeletally immature patients. Methods: A retrospective, matched comparative cohort study was performed of skeletally immature patients who underwent transphyseal ACL reconstruction between January 1, 2008 and March 31, 2011. All skeletally immature patients between ten and fifteen years old who underwent independent femoral tunnel drilling and had adequate baseline and post-operative radiographs were analyzed. These patients were matched with a transtibial technique cohort based on age and sex. Demographic characteristics and peri-operative metrics were collected. Radiographic measurements were recorded from pre-operative MRI and post-operative plain radiographs. Results: Twenty patients were analyzed. Between groups, there were significant differences between independent tunnel drilling and transtibial tunnel drilling in the estimated area of physeal disruption (1.64 cm2 vs. 0.74 cm2, P<0.001), femoral (32.1º vs. 72.8º, P<0.001) and tibial (50.1º vs. 60.5º, P=0.003) tunnel angles, medial/lateral location of the femoral tunnel (24.2 mm vs. 36.1 mm from lateral cortex, P=0.001), and distance from the lateral aspect of the distal femoral physis and the femoral tunnel exit (4.7 mm vs. 26.7 mm from the perichondrial ring, P<0.001), respectively. All patients who underwent femoral tunnel drilling at an angle of less than 25º from the transverse axis experienced a greater than 6% disruption of physeal area. There was a significant inverse correlation between femoral tunnel angle and estimated area of femoral physeal involvement (r=-0.8255, P=0.003). Conclusion: With femoral tunnel drilling techniques that create more oblique tunnels, the area of distal femoral physeal damage is larger, more eccentric and closer to the perichondrial ring. Since most

  6. ACL mismatch reconstructions: influence of different tunnel placement strategies in single-bundle ACL reconstructions on the knee kinematics.

    PubMed

    Herbort, Mirco; Lenschow, Simon; Fu, Freddie H; Petersen, Wolf; Zantop, Thore

    2010-11-01

    To evaluate the influence of tibial and femoral tunnel position in ACL reconstruction on knee kinematics, we compared ACL reconstruction with a tibial and femoral tunnel in anteromedial (AM-AM reconstruction) and in posterolateral footprint (PL-PL reconstruction) with a reconstruction technique with tibial posterolateral and femoral anteromedial tunnel placement (PL-AM reconstruction). In 9 fresh-frozen human cadaveric knees, the knee kinematics under simulated Lachman (134 N anterior tibial load) and a simulated pivot shift test (10 N/m valgus and 4 N/m internal tibial torque) were determined at 0°, 30°, 60°, and 90° of flexion. Kinematics were recorded for intact, ACL-deficient, and single-bundle ACL reconstructed knees using three different reconstruction strategies in randomized order: (1) PL-AM, (2) AM-AM and (3) PL-PL reconstructions. Under simulated Lachman test, single-bundle PL-AM reconstruction and PL-PL reconstructions both showed significantly increased anterior tibial translation (ATT) at 60° and 90° when compared to the intact knee. At all flexion angles, AM-AM reconstruction did not show any statistical significant differences in ATT compared to the intact knee. Under simulated pivot shift, PL-AM reconstruction resulted in significantly higher ATT at 0°, 30°, and 60° knee flexion and AM-AM reconstructions showed significantly higher ATT at 30° compared to the intact knee. PL-PL reconstructions did not show any significant differences to the intact knee. AM-AM reconstructions restore the intact knee kinematics more closely when compared to a PL-AM technique resembling a transtibial approach. PL-PL reconstructions showed increased ATT at higher flexion angles, however, secured the rotational stability at all flexion angles. Due to the independent tibial and femoral tunnel location, a medial portal technique may be superior to a transtibial approach. PMID:20461359

  7. Quality of Movement for Athletes Six Months Post ACL Reconstruction

    PubMed Central

    deMille, Polly; Nguyen, Joseph; Brown, Allison; Do, Huong; Selvaggio, Elizabeth; Chiaia, Theresa

    2016-01-01

    Objectives: Anterior cruciate ligament (ACL) injury prevention programs evaluate quality of movement (QM) to identify and correct high-risk movement patterns. However, return to play (RTP) decisions post-ACL reconstruction (ACLR) are often based on non-sport relatedquantitative measures such as isokinetic tests and/or time from surgery, with six months post-ACLR being a common expectation for RTP. The purpose of this study was to evaluate whether athletes are ready to RTP 6 months post ACLR using a QM assessment (QMA). Methods: A QMA including nine dynamic tasks (squat, single leg [SL] stance, step down, SL squat, jump in place, side to side jump, broad jump, hop to opposite, SL hop) progressing from double- to single-limb vertical and horizontal movements was administered to 136 athletes at five to seven months post-ACLR. Tasks were viewed from the frontal and sagittal planes by a physical therapist and performance specialist. Movements were evaluated live for risk factors associated with ACL injury (strategy, depth, control, symmetry, and alignment). The proportion of patients exhibiting risky movement patterns for each task was calculated. Fisher’s Exact test was used to determine if there were differences in movement patterns between males and females. Results: The proportion of patients demonstrating risky movement patterns for a task ranged from 48% to 100%. All 136 patients exhibited risky movement patterns for at least one task and 60% of patients displayed risky movement patterns in five or more of the nine tasks. Rates of risky movement patterns were not different between males and females for all tasks (P>0.1 for all tasks). Conclusion: Six months has been cited as a probable time for RTP post-ACLR; thus this is the expectation of the athlete. Our data show that athletes demonstrate multiple QM patterns associated with initial ACL injury, as well as 2nd injury at five to seven months post-operatively. Altered movement patterns evident in tasks as

  8. Over the top or endobutton for ACL reconstruction?

    PubMed

    Verdano, Michele Arcangelo; Pedrabissi, Bianca; Lunini, Enricomaria; Pellegrini, Andrea; Ceccarelli, Francesco

    2012-08-01

    There are an estimated 80-100,000 ACL repairs in the US each year: most ACL tears occurs from noncontact injuries. The 3.9% of the knee ligament injuries undergoes surgery: in the 80% of these patients, this means ACL reconstruction. The purpose of this study is to compare two surgical techniques normally used for acl recustruction; the first one is the intra- extra articular technique with single bundle fixed with staples and the second one is the intra-articular technique with double bundle and endobutton post-fixation. We evaluate the clinical outcome of our patients at the time of 4 years follow up. From January 2006 to April 2009 40 patients underwent to ACL reconstruction, all operated by using hamstring tendons: 20 patients with an average age of 28,75 years (12 men and 8 women) underwent surgery using the intra-extra articular technique, whereas the remaining 20 patients with an average age of 34,5 years (11 men and 9 women) benefited the intra-articular technique with double bundle ligament and endobutton post-fixation. Our study shows no substancial difference between these'two technique, but clinical outcome measures (I.K.D.C., Lysholm and Tegner) estimated better results for the double bundle technique with Endobutton post-fixation. (www.actabiomedica.it).

  9. USE OF SPATIOTEMPORAL GAIT PARAMETERS TO DETERMINE RETURN TO SPORTS AFTER ACL RECONSTRUCTION

    PubMed Central

    LEPORACE, GUSTAVO; METSAVAHT, LEONARDO; ZEITOUNE, GABRIEL; MARINHO, THIAGO; OLIVEIRA, TAINÁ; PEREIRA, GLAUBER RIBEIRO; OLIVEIRA, LISZT PALMEIRA DE; BATISTA, LUIZ ALBERTO

    2016-01-01

    Objective : To compare gait spatiotemporal parameters of healthy and ACL reconstructed subjects in order to classify the status of gait normality. Methods : Fourteen healthy subjects and eight patients submitted to ACL reconstruction walked along a walkway while the lower limbs movement was captured by an infrared camera system. The frames where the initial contact and toe-off took place were determined and the following dependent variables, which were compared between groups through the Mann-Whitney test (a=0.05) were calculated: percentage of time in initial double stance, percentage of time in single stance, percentage of time in terminal double stance, stride length and gait velocity. Initially, all variables were compared between groups using a Mann-Whitney test. A logistic regression was applied, including all dependent variables, to create a model that could differentiate healthy and ACL reconstructed subjects. Results : ACL reconstructed group showed no differences in any spatiotemporal parameter of gait (p > 0.05) in relation to the control group, although the angular kinematic differences of the knee remained altered, as evidenced in a study with a similar sample. Conclusion : The regression classified all subjects as healthy, including the ACL reconstructed group, suggesting the spatiotemporal variables should not be used as the sole criterion of return to sports activities at the same level as prior to injury. Level of Evidence III, Case Control Study. PMID:26981039

  10. Knee instability scores for ACL reconstruction.

    PubMed

    Rahnemai-Azar, Ata A; Naendrup, Jan-Hendrik; Soni, Ashish; Olsen, Adam; Zlotnicki, Jason; Musahl, Volker

    2016-06-01

    Despite abundant biological, biomechanical, and clinical research, return to sport after anterior cruciate ligament (ACL) injury remains a significant challenge. Residual rotatory knee laxity has been identified as one of the factors responsible for poor functional outcome. To improve and standardize the assessment of knee instability, a variety of instability scoring systems is available. Recently, devices to objectively quantify static and dynamic clinical exams have been developed to complement traditional subjective grading systems. These devices enable an improved evaluation of knee instability and possible associated injuries. This additional information may promote the development of new treatment algorithms and allow for individualized treatment. In this review, the different subjective laxity scores as well as complementary objective measuring systems are discussed, along with an introduction of injury to an individualized treatment algorithm. PMID:26980119

  11. Functional Performance Testing and Patient Reported Outcomes following ACL Reconstruction: A Systematic Scoping Review.

    PubMed

    Almangoush, Adel; Herrington, Lee

    2014-01-01

    Objective. A systematic scoping review of the literature to identify functional performance tests and patient reported outcomes for patients who undergo anterior cruciate ligament (ACL) reconstruction and rehabilitation that are used in clinical practice and research during the last decade. Methods. A literature search was conducted. Electronic databases used included Medline, PubMed, Cochrane Library, EMBASE, CINAHL, SPORTDiscus, PEDro, and AMED. The inclusion criteria were English language, publication between April 2004 and April 2014, and primary ACL reconstruction with objective and/or subjective outcomes used. Two authors screened the selected papers for title, abstract, and full-text in accordance with predefined inclusion and exclusion criteria. The methodological quality of all papers was assessed by a checklist of the Critical Appraisal Skills Programme (CASP). Results. A total of 16 papers were included with full-text. Different authors used different study designs for functional performance testing which led to different outcomes that could not be compared. All papers used a measurement for quantity of functional performance except one study which used both quantity and quality outcomes. Several functional performance tests and patient reported outcomes were identified in this review. Conclusion. No extensive research has been carried out over the past 10 years to measure the quality of functional performance testing and control stability of patients following ACL reconstruction. However this study found that the measurement of functional performance following ACL reconstruction consisting of a one-leg hop for a set distance or a combination of different hops using limb symmetry index (LSI) was a main outcome parameter of several studies. A more extensive series of tests is suggested to measure both the quantitative and qualitative aspects of functional performance after the ACL reconstruction. The KOOS and the IKDC questionnaires are both measures that

  12. Functional Performance Testing and Patient Reported Outcomes following ACL Reconstruction: A Systematic Scoping Review

    PubMed Central

    Herrington, Lee

    2014-01-01

    Objective. A systematic scoping review of the literature to identify functional performance tests and patient reported outcomes for patients who undergo anterior cruciate ligament (ACL) reconstruction and rehabilitation that are used in clinical practice and research during the last decade. Methods. A literature search was conducted. Electronic databases used included Medline, PubMed, Cochrane Library, EMBASE, CINAHL, SPORTDiscus, PEDro, and AMED. The inclusion criteria were English language, publication between April 2004 and April 2014, and primary ACL reconstruction with objective and/or subjective outcomes used. Two authors screened the selected papers for title, abstract, and full-text in accordance with predefined inclusion and exclusion criteria. The methodological quality of all papers was assessed by a checklist of the Critical Appraisal Skills Programme (CASP). Results. A total of 16 papers were included with full-text. Different authors used different study designs for functional performance testing which led to different outcomes that could not be compared. All papers used a measurement for quantity of functional performance except one study which used both quantity and quality outcomes. Several functional performance tests and patient reported outcomes were identified in this review. Conclusion. No extensive research has been carried out over the past 10 years to measure the quality of functional performance testing and control stability of patients following ACL reconstruction. However this study found that the measurement of functional performance following ACL reconstruction consisting of a one-leg hop for a set distance or a combination of different hops using limb symmetry index (LSI) was a main outcome parameter of several studies. A more extensive series of tests is suggested to measure both the quantitative and qualitative aspects of functional performance after the ACL reconstruction. The KOOS and the IKDC questionnaires are both measures that

  13. The Effects of Balance Training on Static and Dynamic Postural Stability Indices After Acute ACL Reconstruction

    PubMed Central

    Akbari, Asghar; Ghiasi, Fateme; Mir, Mohsen; Hosseinifar, Mohammad

    2016-01-01

    Background: Proprioception and postural stability play an important role in knee movements. However, there are controversies about the overall recovery time of proprioception following knee surgery and onset of balance and neuromuscular training after ACL reconstruction. Therefore, it is necessary to evaluate the effect of balance training in early stage of knee rehabilitation after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to evaluate the effect of balance exercises on postural stability indices in subjects with anterior cruciate ligament (ACL) reconstruction. Methods: The study was a controlled randomized trial study. Twenty four patients who had ACL reconstructed (balance training group) and twenty four healthy adults without any knee injury (control group) were recruited in the study. The balance exercises group performed balance exercises for 2 weeks. Before and after the interventions, overall, anteroposterior, and mediolateral stability indices were measured with a Biodex Balance System in bilateral and unilateral stance positions with the eyes open and closed. T-tests were used for statistical analysis (p<0.05). Results: Results showed that amount of static stability indices did not change after training and there were not significant differences in static stability indices before and after balance training (p>0.05). Although amount of dynamic stability indices decreased, there were not significant differences in dynamic stability indices before and after balance training (p>0.05). Amount of dynamic stability indices were decreased in balance training group, however, there were not significant differences between groups (p>0.05). Conclusion: These results support that balance exercise could partially improved dynamic stability indices in early stage of ACL reconstruction rehabilitation. The results of this study suggest that balance exercises should be part of the rehabilitation program following ACL reconstruction. PMID

  14. KNEE SYNERGISM DURING GAIT REMAIN ALTERED ONE YEAR AFTER ACL RECONSTRUCTION

    PubMed Central

    LEPORACE, GUSTAVO; METSAVAHT, LEONARDO; PEREIRA, GLAUBER RIBEIRO; OLIVEIRA, LISZT PALMEIRA DE; CRESPO, BERNARDO; BATISTA, LUIZ ALBERTO

    2016-01-01

    ABSTRACT Objective: To compare the activation of the vastus lateralis (VL) and biceps femoris (BF) muscles during gait, as well VL/BF muscular co-contraction (MCC) between healthy (CG) and anterior cruciate ligament reconstructed (ACL-R) subjects. Methods: Nineteen subjects, ten controls and nine ACL-R patients had a VL and BF electromyogram (EMG) captured to calculate the MCC ratio. A Principal Component (PC) Analysis was applied to reduce the dimensionality effect of each of the MCC, VL and BF curves for both healthy and ACL reconstructed groups. The PC scores were used to calculate the standard distance (SD). SD values were employed in order to compare each dependent variable (MCC, VL and BF) between the two groups using unpaired t-test. Results: ACL-R group presented a lower VL activation at the beginning and at the end of the gait cycle, as compared to the control group. However, no difference was found for BF or VL/BF MCC. Conclusion: The gait analysis of ACL reconstructed patients demonstrated a persistent deficit in VL activation when compared to the control group, even one year after surgery. Level of Evidence III. Case Control Study PMID:27217814

  15. Rash After ACL Reconstruction: Asking the Right Questions.

    PubMed

    Smith, Andrew H; Bach, Bernard R

    2004-10-01

    A 40-year-old recreational athlete injured his left knee on a "moon bouncer" at his child's birthday party. Before the injury, he regularly went hiking and downhill skiing and played basketball and tennis. Because the injury caused persistent symptoms of knee instability, he elected to undergo an anterior cruciate ligament (ACL) reconstruction using allograft. At the time of surgery, the patient's skin examination was unremarkable, and no surgical complications were noted. The patient went home on the day of surgery.

  16. Successful feed-forward strategies following ACL injury and reconstruction.

    PubMed

    Bryant, Adam L; Newton, Robert U; Steele, Julie

    2009-10-01

    The purpose of this study was to elucidate the most successful feed-forward strategies responsible for enhancing dynamic restraint following anterior cruciate ligament (ACL) injury and ACL reconstruction (ACLR). Ten male ACL deficient (ACLD) subjects (18-35 years) together with 27 matched males who had undergone ACLR (14 using a patella tendon graft and 13 using a combined semitendinosus and gracilis graft) and 22 matched-control subjects were recruited. After their knee functionality (0- to 100-point scale) was rated using the Cincinnati Knee Rating System, each subject performed a maximal, countermovement hop for distance on their involved limb while EMG data were collected from the vastus lateralis (VL), vastus medialis (VM), semitendinosus (ST) and biceps femoris (BF) muscles. Acceleration transients at the proximal tibia were recorded using a uniaxial accelerometer mounted at the level of the tibial tuberosity. Whilst pre-programmed muscle activation strategies and tibial acceleration transients when landing from a single-leg long hop for distance were not contingent upon ACL status, a number of significant correlations were identified between neuromuscular variables and knee functionality of ACLD and ACLR subjects. Increased hamstring preparatory activity together with a greater ability to control tibial motion during dynamic deceleration was associated with higher levels of knee functionality in the ACLD subjects. Successful feed-forward strategies following ACLR were related to graft selection; STGT subjects with superior knee function activated their quadriceps earlier and were better able to synchronise peak hamstring muscle activity closer to initial ground contact whilst more functional PT subjects demonstrated enhanced tibial control despite a lack of evidence supporting modified pre-programmed muscular activation patterns. Our conclusion was that more functional individuals used sensory feedback to build treatment-specific, feed-forward strategies to

  17. Performance and return-to-sport after ACL reconstruction in NFL quarterbacks.

    PubMed

    Erickson, Brandon J; Harris, Joshua D; Heninger, Jacob R; Frank, Rachel; Bush-Joseph, Charles A; Verma, Nikhil N; Cole, Brian J; Bach, Bernard R

    2014-08-01

    Anterior cruciate ligament (ACL) rupture is a significant injury in National Football League (NFL) quarterbacks. The purpose of this study was to determine (1) return-to-sport (RTS) rate in NFL quarterbacks following ACL reconstruction, (2) performance upon RTS, and (3) the difference in RTS and performance between players who underwent ACL reconstruction and controls. Thirteen quarterbacks (14 knees) who met inclusion criteria underwent ACL reconstruction while in the NFL. Matched controls were selected from the NFL during the same time span to compare and analyze age, body mass index (BMI), position, performance, and NFL experience. Student t tests were performed for analysis of within- and between-group variables. Bonferroni correction was used in the setting of multiple comparisons. Twelve quarterbacks (13 knees; 92%) were able to RTS in the NFL. Mean player age was 27.2±2.39 years. Mean career length in the NFL following ACL reconstruction was 4.85±2.7 years. Only 1 player needed revision ACL reconstruction. In both cases and controls, player performance was not significantly different from preinjury performance after ACL reconstruction (or index year in controls). There was also no significant performance difference between case and control quarterbacks following ACL reconstruction (or index year in controls). There is a high rate of RTS in the NFL following ACL reconstruction. In-game performance following ACL reconstruction was not significantly different from preinjury or from controls.

  18. Predictors of Lateral Compartment Joint Space Difference at a Minimum of Two Years after ACL Reconstruction

    PubMed Central

    Jones, Morgan H.; Reinke, Emily; Duryea, Jeffrey; Fleming, Braden C.; Obuchowski, Nancy; Winalski, Carl S.; Spindler, Kurt P.

    2016-01-01

    Objectives: ACL reconstruction effectively restores knee stability and allows a return to athletic activities after ACL injury, but patients are still at higher risk of developing post-traumatic OA. Patient reported outcomes from the Multicenter Orthopaedic Outcomes Network (MOON) prospective longitudinal cohort of over 1500 patients undergoing ACL reconstruction showed no increase in OA symptoms (KOOS subscale) at 2 or 6 years after surgery. Therefore, identification of structural changes of OA that may precede the onset of symptoms is of critical importance for determining risk factors for the initiation and progression of post-traumatic OA in addition to measuring the effectiveness of potential disease-modifying treatments. One structural measure of OA is radiographic joint space width (JSW). We previously demonstrated that meniscus treatment and age predict narrower medial compartment JSW. Methods: 335 patients from the MOON cohort (154 males, 181 females, median age 18 years at the time of surgery) were recruited at a minimum of 2 years following surgery for on-site evaluations including bilateral metatarsophalangeal joint (MTP) radiographs to assess JSW. To minimize bias related to pre-existing knee injury or OA, subjects were 35 years or younger, were injured playing a sport, had primary ACL reconstruction without prior meniscus or articular cartilage surgery, did not undergo subsequent ACL revision, and had a surgically normal contralateral knee. Radiographic JSW was measured in the lateral compartment of both knees using a validated semiautomated method. The association of age, sex, BMI, meniscus treatment, and articular cartilage treatment with lateral compartment JSW differences (JSD) between the reconstructed and normal knees was examined using multivariable generalized linear models. The Holm-Bonferroni method was used to account for multiple comparisons. Results: The mean lateral compartment JSW was 7.73 mm and (95% CI 7.61-7.85 mm) for ACL

  19. Strength Asymmetry and Landing Mechanics at Return to Sport after ACL Reconstruction

    PubMed Central

    Schmitt, Laura C.; Paterno, Mark V.; Ford, Kevin R.; Myer, Gregory D.; Hewett, Timothy E.

    2014-01-01

    Purpose Evidence-based quadriceps femoris muscle (QF) strength guidelines for return to sport following anterior cruciate ligament (ACL) reconstruction are lacking. This study investigated the impact of QF strength asymmetry on knee landing biomechanics at the time of return to sport following ACL reconstruction. Methods Seventy-seven individuals (17.4 years) at the time of return to sport following primary ACL reconstruction (ACLR group) and 47 uninjured control individuals (17.0 years) (CTRL group) participated. QF strength was assessed and Quadriceps Index calculated (QI = [involved strength/uninvolved strength]*100%). The ACLR group was sub-divided based on QI: High Quadriceps (HQ, QI≥90%) and Low-Quadriceps (LQ, QI<85%). Knee kinematic and kinetic variables were collected during a drop vertical jump maneuver. Limb symmetry during landing, and discrete variables were compared among the groups with multivariate analysis of variance and linear regression analyses. Results The LQ group demonstrated worse asymmetry in all kinetic and ground reaction force variables compared to the HQ and CTRL groups, including reduced involved limb peak knee external flexion moments (p<.001), reduced involved limb (p=.003) and increased uninvolved limb (p=.005) peak vertical ground reaction forces, and higher uninvolved limb peak loading rates (p<.004). There were no differences in the landing patterns between the HQ and CTRL groups on any variable (p>.05). In the ACLR group, QF strength estimated limb symmetry during landing after controlling for graft type, meniscus injury, knee pain and symptoms. Conclusion At the time of return to sport, individuals post-ACL reconstruction with weaker QF demonstrate altered landing patterns. Conversely, those with nearly symmetrical QF strength demonstrate landing patterns similar to uninjured individuals. Consideration of an objective QF strength measure may aid clinical decision-making to optimize sports participation following ACL

  20. Recovery of Psychological Readiness May Differ Between Genders Following ACL Reconstruction in Adolescent Athletes

    PubMed Central

    Milewski, Matthew David; Kostyun, Regina; Iannicelli, Julie P.; Kostyun, Kyle J.; Solomito, Matthew; Nissen, Carl W.

    2016-01-01

    Objectives: Injury to the anterior cruciate ligament (ACL) is a traumatic and emotional event for adolescent athletes. Preparation to return to play (RTP) and the potential risk of re-injury are often equally as emotional as the injury, and have been identified as possible limiting factors to a successful rehabilitation and RTP. In order to create a comprehensive rehabilitation model, further understanding of psychological readiness following surgical intervention is needed. The purpose of this study was to determine if clinical outcomes of subjective knee function and psychological readiness differ between genders following ACL reconstruction surgery in adolescent athletes, and if higher knee function and physiological readiness was associated with an earlier to RTP. Methods: Athletes who underwent ACL reconstruction surgery and were successfully returned back to unrestricted sport were included in the analysis. At approximately six months post surgery, knee function was assessed using the validated International Knee Documentation Committee (IKDC) Subjective Form, and psychological readiness was assessed using the validated ACL-Return to Sport after Injury (ACL-RSI) scale. Formal clearance to resume unrestricted sport was obtained from clinic notes. A T-test was used to determine if demographics, IKDC and ACL-RSI scores between genders. A mixed effects random intercept regression model was used to determine the association of time to RTP with IKDC and ACL-RSI scores. Results: A total of 45 adolescent athletes (23 females) were included in this analysis. No significant differences were found between males and females for age (16.2±1.5 years, 16.3±2.2 years) and average time to RTP (7.3±2.0 months, 7.3±1.8 months). No significant differences in IKDC scores were found between males and females (88±10%, 87±10%). A trend was identified that males demonstrated higher ACL-RSI scores at six month post surgery than females (81±14%, 72±17%, p = 0.063). In females

  1. Fifteen Year Prospective Comparison of Patellar & Hamstring Tendon Grafts for ACL Reconstruction

    PubMed Central

    Roe, Justin; Salmon, Lucy; Kok, Alison; Linklater, James; Pinczewski, Leo

    2016-01-01

    Objective: This prospective longitudinal study compares isolated endoscopic ACL reconstruction utilizing 4-strand hamstring tendon (HT) or patellar tendon (PT) autograft over a 15-year period with respect to clinical outcomes and the development of osteoarthritis. Method: 90 consecutive patients with isolated ACL rupture were reconstructed with a PT autograft and 90 patients received HT autograft, with an identical surgical technique. Patients were assessed at 2, 5, 7, 10 and 15 years. Assessment included the IKDC Knee Ligament Evaluation including radiographic evaluation, KT1000, kneeling pain, and clinical outcomes. Results: Subjects who received the PT graft had significantly worse outcomes at 15 years for the variables of radiologically detectable osteoarthritis (p=0.001), motion loss (p=0.02), single leg hop test (p=0.002), participation in strenuous activity (p=0.03), knee related decrease in activity level (p=0.002) and kneeling pain (p=0.03). There was no significant difference between the HT and PT groups in overall IKDC grade (p=0.28). ACL graft rupture occurred in 16% of HT group and 8% of the PT group (p=0.10). Contralateral ACL rupture occurred in significantly more PT patients (24%) than HT patients (12%) (p=0.03). Conclusion: Significant differences have developed at 15 years after surgery which were not seen at earlier reviews. Compared to the HT Group, the PT group had significantly worse outcomes with respect to radiological osteoarthritis, range of motion and functional tests but no significant difference in laxity was identified. There was a high incidence of ACL injury after reconstruction, to both the reconstructed and the contralateral knee.

  2. A canine hybrid double-bundle model for study of arthroscopic ACL reconstruction.

    PubMed

    Cook, James L; Smith, Patrick A; Stannard, James P; Pfeiffer, Ferris M; Kuroki, Keiichi; Bozynski, Chantelle C; Cook, Cristi R

    2015-08-01

    Development and validation of a large animal model for pre-clinical studies of intra-articular anterior cruciate ligament (ACL) reconstruction that addresses current limitations is highly desirable. The objective of the present study was to investigate a translational canine model for ACL reconstruction. With institutional approval, adult research hounds underwent arthroscopic debridement of the anteromedial bundle (AMB) of the ACL, and then either received a tendon autograft for "hybrid double-bundle" ACL reconstruction (n = 12) or no graft to remain ACL/AMB-deficient (n = 6). Contralateral knees were used as non-operated controls (n = 18) and matched canine cadaveric knees were used as biomechanical controls (n = 6). Dogs were assessed using functional, diagnostic imaging, gross, biomechanical, and histologic outcome measures required for pre-clinical animal models. The data suggest that this canine model was able to overcome the major limitations of large animal models used for translational research in ACL reconstruction and closely follow clinical aspects of human ACL reconstruction. The "hybrid double-bundle" ACL reconstruction allowed for sustained knee function without the development of osteoarthritis and for significantly improved functional, diagnostic imaging, gross, biomechanical, and histologic outcomes in grafted knees compared to ACL/AMB-deficient knees.

  3. Acute Vs Delayed ACL Reconstruction. Early Differences and Preliminary Two Year Results

    PubMed Central

    Eriksson, Karl; Barenius, Björn

    2016-01-01

    Objectives: Historically acute ACL reconstruction has been avoided due to reports of early rehabilitation problems with stiffness. Are these reports still valid today with modern arthroscopic techniques? Methods: 70 patients with a high recreational activity level (Tegner ≥6) who presented with a acute ACL injury were randomized to an acute reconstruction within 8 days from the injury or delayed reconstruction after 6-10 weeks. Four surgeons performed the ACL reconstructions with quadrupled semitendinosus tendon grafts and endobutton and metallic interference screw fixation. The rehabilitation training was performed at the same physiotherapy center for all patients. The follow up at 6 and 24 months included ROM, Lachman, Rolimeter, pivot shift, one leg hop, IKDC, KOOS, Lysholm and Tegner activity level. Results: There were no differences between the groups in ROM, IKDC, activity level or laxity at 6 months. Four patients had a combined extension and flexion deficit of more than 15 degrees, two from each group. In the acute group 79% had an objective IKDC grade A or B compared with 73% in the delayed group. The one leg hop index above 90% was found in 50% in the acute group and 24% in the delayed group (p=0.04). Functional data for the 2-year follow up are not available at the time of abstract writing. The median activity level according to Tegner was restored to pre-injury levels in both groups after one year, and was stationary at 2 years. The visual analogue scale (VAS) response to the question “How is your knee working on a scale from 0-100? (100 = best)” revealed 81 in the acute and 71 in the delayed group (p=0.1). To the question “How does your knee affect your activity level on a scale from 0-100? (100 = no affection)” the mean score was 75 in the acute group and 67 in the delayed group (p=0.3). At one and two years the KOOS was statistically similar between the groups but with slightly higher subscale “Sport and recreation” scores, 85 in the

  4. Utilization of Modified NFL Combine Testing to Identify Functional Deficits in Athletes Following ACL Reconstruction

    PubMed Central

    MYER, GREGORY D.; SCHMITT, LAURA C.; BRENT, JENSEN L.; FORD, KEVIN R.; BARBER FOSS, KIM D.; SCHERER, BRADLEY J.; HEIDT, ROBERT S.; DIVINE, JON G.; HEWETT, TIMOTHY E.

    2012-01-01

    STUDY DESIGN Case control. OBJECTIVES To use modified NFL Combine testing methodology to test for functional deficits in athletes following anterior cruciate ligament (ACL) reconstruction following return to sport. BACKGROUND There is a need to develop objective, performance-based, on-field assessment methods designed to identify potential lower extremity performance deficits and related impairments in this population. METHODS Eighteen patients (mean ± SD age, 16.9 ± 2.1 years; height, 170.0 ± 8.7 cm; body mass, 71.9 ± 21.8 kg) who returned to their sport within a year following ACL reconstruction (95% CI: 7.8 to 11.9 months from surgery) participated (ACLR group). These individuals were asked to bring 1 or 2 teammates to serve as control participants, who were matched for sex, sport, and age (n = 20; mean ± SD age, 16.9 ± 1.1 years; height, 169.7 ± 8.4 cm; body mass, 70.1 ± 20.7 kg). Functional performance was tested using the broad jump, vertical jump, modified long shuttle, modified pro shuttle, modified agility T-test, timed hop, triple hop, single hop, and crossover hop tests. A 1-way multivariate analysis of variance (MANOVA) was used to evaluate group differences for dependent performance variables. RESULTS The functional performance measurements of skills requiring bilateral involvement of both lower extremities showed no group differences between the ACLR and control groups (P>.05). An overall group difference (P = .006) was observed for the combined limb symmetry index (LSI) measures. However, the modified double-limb performance tasks (long shuttle, modified agility T-test, and pro shuttle) were not, independently, sufficiently sensitive to detect limb deficits in individuals with ACL reconstruction. Conversely, the LSI on the distance measures of the single-limb performance tasks all provided moderate to large effect sizes to differentiate between the ACLR and control groups, as the individuals who had ACL reconstruction demonstrated involved

  5. Prognosis and Predictors of ACL Reconstructions using the MOON Cohort: A Model for Comparative Effectiveness Studies

    PubMed Central

    Spindler, Kurt P.; Parker, Richard D.; Andrish, Jack T.; Kaeding, Christopher C.; Wright, Rick W.; Marx, Robert G.; McCarty, Eric C.; Amendola, Annunziato; Dunn, Warren R.; Huston, Laura J.; Harrell, Frank E.

    2012-01-01

    Injury to the anterior cruciate ligament (ACL) threatens an active lifestyle and exposes the patient to risk of early osteoarthritis (OA). ACL reconstruction is typically chosen by individuals to allow a return to their previous work and sports activities. Primary ACL reconstruction (ACLR) has in general been effective at restoring functional stability, but patients’ modifiable predictors of both short- and long-term validated outcomes and OA are largely unknown. The Multicenter Orthopaedic Outcomes Network (MOON) consortium was established in 2002 to enroll and longitudinally follow a population cohort of ACL reconstructed patients. The objective was to establish patient-specific predictive models of clinically important outcomes. Over the past 10 years, the overarching aims of this NIAMS-funded prospective multicenter cohort of ACL reconstructions has been three-fold: 1) to identify both short- and long-term prognosis and predictors of sports function, activity level, and general health through validated patient-reported outcomes, 2) to identify the symptoms and signs of OA, and 3) to quantify the incidence of ACL reconstruction graft and/or contralateral ACL failures and additional surgical procedures. This manuscript summarizes the Kappa Delta Ann Doner Vaughan Award paper and presentation at the 2012 ORS/AAOS Annual Meeting. PMID:22912340

  6. Meniscus treatment and age associated with narrower radiographic joint space width 2 – 3 years after ACL reconstruction: Data from the MOON onsite cohort

    PubMed Central

    Jones, Morgan H.; Spindler, Kurt P.; Fleming, Braden C.; Duryea, Jeffrey; Obuchowski, Nancy A.; Scaramuzza, Erica A.; Oksendahl, Heidi L.; Winalski, Carl S.; Duong, Carol L.; Huston, Laura J.; Parker, Richard D.; Kaeding, Christopher C.; Andrish, Jack T.; Flanigan, David C.; Dunn, Warren R.; Reinke, Emily K.

    2015-01-01

    Objective To identify risk factors for radiographic signs of post-traumatic OA 2–3 years after ACL reconstruction through multivariable analysis of minimum joint space width (mJSW) differences in a specially designed nested cohort. Methods A nested cohort within the Multicenter Orthopaedic Outcomes Network cohort included 262 patients (148 females, average age 20) injured in sport who underwent ACL reconstruction in a previously uninjured knee, were 35 or younger, and did not have ACL revision or contralateral knee surgery. mJSW on semi-flexed radiographs was measured in the medial compartment using a validated computerized method. A multivariable generalized linear model was constructed to assess mJSW difference between the ACL reconstructed and contralateral control knees while adjusting for potential confounding factors. Results Unexpectedly, we found the mean mJSW was 0.35 mm wider in ACL reconstructed than in control knees (5.06 mm (95% CI 4.96 – 5.15 mm) versus 4.71 mm (95% CI 4.62 – 4.80 mm), p<0.001). However, ACL reconstructed knees with meniscectomy had narrower mJSW compared to contralateral normal knees by 0.64 mm (95% C.I. 0.38 – 0.90 mm) (p<0.001). Age (p<0.001) and meniscus repair (p=0.001) were also significantly associated with mJSW difference. Conclusion Semi-flexed radiographs can detect differences in mJSW between ACL reconstructed and contralateral normal knees 2–3 years following ACL reconstruction, and the unexpected wider mJSW in ACL reconstructed knees may represent the earliest manifestation of post-traumatic osteoarthritis and warrants further study. PMID:25559582

  7. Positive culture in allograft ACL-reconstruction: what to do?

    PubMed

    Díaz-de-Rada, P; Barriga, A; Barroso, J L; García-Barrecheguren, E; Alfonso, M; Valentí, J R

    2003-07-01

    The transmission of disease or infection from the donor to the recipient is always a risk with the use of allografts. We carried out a research study on the behavioural pattern of implanted allografts, which were initially stored in perfect conditions (all cultures being negative) but later presented positive cultures at the implantation stage. Because there is no information available on how to deal with this type of situation, our aim was to set guidelines on the course of action which would be required in such a case. We conducted a retrospective study of 181 patients who underwent an ACL reconstruction using BPTB allografts. All previous bone and blood cultures and tests for hepatitis B and C, syphilis and HIV were negative. An allograft sample was taken for culture in the operating theatre just before its implantation. The results of the cultures were obtained 3-5 days after the operation. We had 24 allografts with positive culture (13.25%) after the implantation with no clinical infection in any of these patients. Positive cultures could be caused by undetected contamination while harvesting, storing or during manipulation before implantation. The lack of clinical signs of infection during the follow-up of our patients may indicate that no specific treatment-other than an antibiotic protocol-would be required when facing a case of positive culture of a graft piece after its implantation.

  8. Positive culture in allograft ACL-reconstruction: what to do?

    PubMed

    Díaz-de-Rada, P; Barriga, A; Barroso, J L; García-Barrecheguren, E; Alfonso, M; Valentí, J R

    2003-07-01

    The transmission of disease or infection from the donor to the recipient is always a risk with the use of allografts. We carried out a research study on the behavioural pattern of implanted allografts, which were initially stored in perfect conditions (all cultures being negative) but later presented positive cultures at the implantation stage. Because there is no information available on how to deal with this type of situation, our aim was to set guidelines on the course of action which would be required in such a case. We conducted a retrospective study of 181 patients who underwent an ACL reconstruction using BPTB allografts. All previous bone and blood cultures and tests for hepatitis B and C, syphilis and HIV were negative. An allograft sample was taken for culture in the operating theatre just before its implantation. The results of the cultures were obtained 3-5 days after the operation. We had 24 allografts with positive culture (13.25%) after the implantation with no clinical infection in any of these patients. Positive cultures could be caused by undetected contamination while harvesting, storing or during manipulation before implantation. The lack of clinical signs of infection during the follow-up of our patients may indicate that no specific treatment-other than an antibiotic protocol-would be required when facing a case of positive culture of a graft piece after its implantation. PMID:12827226

  9. Treatment of persistent extraarticular infection using a temporary cement spacer on the tibia after ACL reconstruction.

    PubMed

    Jung, Kwang Am; Lee, Soo Chan; Song, Moon Bok; Lee, Choon Key

    2008-01-01

    Postoperative infection after anterior cruciate ligament (ACL) reconstruction is an uncommon but serious complication. Although several treatments for intraarticular infection have been reported, no report has been recorded on the treatment of persistent extraarticular infections. The authors experienced reconstructed graft removal due to a refractory extraarticular infection on tibia. Early ACL reimplantation was performed using a temporary cement spacer containing antibiotics and a irradiated bone patellar tendon bone allograft.

  10. Treatment of persistent extraarticular infection using a temporary cement spacer on the tibia after ACL reconstruction.

    PubMed

    Jung, Kwang Am; Lee, Soo Chan; Song, Moon Bok; Lee, Choon Key

    2008-01-01

    Postoperative infection after anterior cruciate ligament (ACL) reconstruction is an uncommon but serious complication. Although several treatments for intraarticular infection have been reported, no report has been recorded on the treatment of persistent extraarticular infections. The authors experienced reconstructed graft removal due to a refractory extraarticular infection on tibia. Early ACL reimplantation was performed using a temporary cement spacer containing antibiotics and a irradiated bone patellar tendon bone allograft. PMID:17899003

  11. Knee Hyperextension as a Predictor of Failure in Revision ACL Reconstruction

    PubMed Central

    Cooper, Daniel E.; Dunn, Warren R.; Wright, Rick W.; Haas, Amanda; Huston, Laura J.

    2016-01-01

    Objectives: We studied the minimum 2 year follow-up outcomes in an ACL revision cohort. The hypothesis is that knees that hyperextend will have a worse outcome and greater odds of graft failure than knees that do not hyperextend. The null hypothesis is that there is no difference in outcomes or graft rupture between the two groups. Methods: Revision ACL reconstruction patients were identified and prospectively enrolled between 2006 and 2011. Data collected included baseline demographics, surgical technique and pathology, and a series of validated patient reported outcome instruments (IKDC, KOOS, WOMAC, and Marx activity rating score). Patients were followed up for 2 years, and asked to complete the identical set of outcome instruments. A regression model using graft failure as the dependent variable included graft type, age, and hyperextension greater than or equal to 5 degrees yes/no (HE) in order to assess these potential surgical risk factors for clinical outcomes 2 years after revision ACL reconstruction. Results: There were 1,145 subjects included in the analyses. The median age of the cohort was 26 (IQR= 20, 35), and 58% were male. The proportion that were enrolled for their first revision surgery was 88%, their second 10%, and third or greater 2%. The number of subjects categorized as HE was 375 (33%). The median age of subjects that failed was 18, compared to 26 for those with intact grafts. All three variables included in our regression model were significant predictors of graft failure: younger age, inter-quartile range odds ratio (IQROR) = 3.32 (95%CI 1.5, 7.2) p= 0.002; use of allograft OR = 3.1 (95%CI 1.4, 6.9) p= 0.01, and HE 2.1 (95%CI 1.02, 4.42) p= 0.04. Conclusion: The MARS Study Group has previously reported that young age and the use of allograft as a graft source are independent predictors (over 3X odds ratio) of graft rupture after revision ACLR. This study found that knee hyperextension greater than or equal to 5 degrees is present in 1/3 of

  12. Bone tunnel enlargement after ACL reconstruction using autologous hamstring tendons: a CT study

    PubMed Central

    Iorio, Raffaele; Vadalà, Antonio; Argento, Giuseppe; Di Sanzo, Vincenzo

    2006-01-01

    Purpose: To evaluate prospectively the increase in the size of the tibial and femoral bone tunnel following arthroscopic anterior cruciate ligament (ACL) reconstruction with quadrupled-hamstring autograft. Methods: Twenty-five consecutive patients underwent arthroscopic ACL reconstruction with quadrupled-hamstring autograft. Preoperative clinical evaluation was performed using the Lysholm knee score, Tegner activity level, and International Knee Documentation Committee forms and a KT-1000 arthrometer (side to side). Computed tomography (CT) of the femoral and tibial tunnel was performed on the day after operation in all cases and at mean follow-up of 10 months (range 9–11 months).Results: All of the clinical evaluation scales performed showed an overall improvement. The postoperative anterior laxity difference was <3 mm in 16 patients (70%) and 3–5 mm in seven patients (30%). The mean average femoral tunnel diameter increased significantly (3%) from 9.04±0.05 mm postoperatively to 9.3±0.8 mm at 10 months; tibial tunnel increased significantly (11%) from 9.03±0.04 mm to 10±0.8 mm. There were no statistically significant differences between tunnel enlargement, clinical results, and arthrometer evaluation. Conclusions: The rate of tunnel widening observed in this study seems to be lower than that reported in previous studies that used different techniques. We conclude that an anatomical surgical technique and a less aggressive rehabilitation process influenced the amount of tunnel enlargement after ACL reconstruction with doubled hamstrings. PMID:16683112

  13. Magnetic Resonance Imaging of Cartilage Contact and Bound Water in ACL-Deficient and ACL Reconstructed Knees

    PubMed Central

    Baer, Geoffrey Scott; Kaiser, Jarred; Vignos, Michael; Liu, Fang; Smith, Colin Robert; Kijowski, Richard; Thelen, Darryl

    2016-01-01

    Objectives: Osteoarthritis (OA) is common following ACL-reconstructive (ACLR) surgery (6). The cause of early OA is not understood, but theories have focused on osteochondral damage at the time of injury (2) and abnormal joint mechanics following surgical repair (7). In this study, we investigate the inter-relationship of cartilage mechanics and biomarkers of OA in both ACL-deficient (ACLD) and ACLR knees. Our approach employs a novel dynamic MR sequence to measure joint mechanics (3) and the recently developed mcDESPOT to assess regional variations in water bound to proteoglycan (PG) (5). We hypothesize that bound water will be diminished in the cartilage of ACLD knees and, after surgery, will continue to adapt in a manner that reflects altered cartilage loading. This abstract presents initial observations on a cross-section of healthy, ACLD and ACLR knees. Methods: The dominant knees of 8 healthy controls, ACLD knees of 5 patients and ACLR knees of 8 patients were imaged in a 3 T MRI scanner (Table). Controls had no history of pain, injury, or surgery to their knee. Patients had no additional ligament injury and no meniscal damage. ACLD subjects were imaged prior to reconstructive surgery. Femoral and tibial cartilage were segmented from MR images and cartilage thickness was calculated. The mcDESPOT sequence provided a fraction map of water bound to PG (Fpg). Subjects flexed their knee against an inertial load at 0.5 Hz, while a SPGR-VIPR sequence continuously acquired volumetric data. Kinematics were obtained using model tracking of the dynamic images (3). Cartilage was registered to the bone segments for all frames, and contact patterns were characterized by the proximity between surfaces. Spatial representations of tibial cartilage contact, thickness and Fpg were co-registered for each subject. Results: Our initial images suggest lower Fpg values in ACLD knees, primarily on the posterior-lateral tibia. This is also observed in ACLR knees, with additional

  14. Quadriceps function relates to muscle size following ACL reconstruction.

    PubMed

    Kuenze, Christopher M; Blemker, Silvia S; Hart, Joseph M

    2016-09-01

    It remains unclear what role reduced volume and cross-section area (CSA) of individual quadriceps muscles may play in persistent quadriceps weakness and more global dysfunction following ACL reconstruction (ACLR). The purpose of this investigation was to establish the relationship between cross-sectional area of the quadriceps muscle group and measures of knee related and quadriceps function following ACLR. Thirty participants with a history of primary, unilateral ACLR experiencing persistent quadriceps activation failure participated in this cohort study. Clinical factors including International Knee Documentation Committee (IKDC) score, normalized knee extension MVIC torque (Nm/kg) and quadriceps central activation ratio (CAR, %) were assessed in addition to CSA. Quadriceps CSA was measured via magnetic resonance imaging (MRI; Siemens Avanto 1.5T). Quadriceps CSA (cm(2) ) and quadriceps volume (cm(3) ) as well as individual muscle estimates were identified within a 10 cm mid-thigh capture area. Pearson's product-moment correlation coefficients (r) established relationships between CSA and all other variables. Stepwise linear regression established which CSA factors were able to successfully predict clinical factors. Knee extension MVIC torque was strongly correlated with Vastus Intermedius (VI; r =  0.857, p < 0.001) CSA as well as partial VI (r = 0.849, p < 0.001) and quadriceps (r = 0.830, p < 0.001) volume. Partial VI (r = 0.365, p = 0.047) volume was weakly correlated with IKDC score. Knee extension MVIC torque was strongly predicted using VI CSA alone (R(2)  = 0.725) or in combination with Vastus Medialis CSA (VM; R(2)  = 0.756). Statement of Clinical Significance: Atrophy of the VI and VM muscles negatively impacts knee extension strength following ACLR. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1656-1662, 2016.

  15. Gait adaptation in ACL deficient patients before and after anterior cruciate ligament reconstruction surgery.

    PubMed

    Knoll, Zsolt; Kiss, Rita M; Kocsis, László

    2004-06-01

    The objective of this study is to determine how kinematical parameters and electromyography data of selected muscles may change as a result of anterior cruciate ligament (ACL) deficiency and following ACL reconstruction. The study was conducted on 25 anterior cruciate ligament deficient subjects prior to and 6 weeks, 4 months, 8 months and 12 months following ACL reconstructive surgery using the bone-patellar tendon-bone technique. Gait analysis was performed by applying the zebris three-dimensional ultrasound-based system with surface electromyograph (zebris). Kinematic data were recorded for the lower limb. The muscles surveyed include vastus lateralis and medialis, biceps femoris and adductor longus. The results obtained from the injured subjects were compared with those of 51 individuals without any ACL damage whatsoever. Acute ACL deficient patients exhibited a quadriceps avoidance pattern prior to and 6 weeks following surgery. No quadriceps avoidance phenomenon develops in chronic ACL deficient patients. In operated individuals, tempo-spatial parameters and the knee angle regained a normal pattern for the ACL-deficient limb during gait as early as 4 months following surgery. However, the relative ACL movement parameter, which describes the tibial translation into the direction of ACL, and the EMG traces show no significant statistical difference compared with the same values of the healthy control group just 8 months following surgery. The analysis of spatial-temporal parameters and EMG traces show that the development of a quadriceps avoidance pattern is less common than previously reported. These data suggest that anterior cruciate ligament deficiency and reconstruction produce considerable changes in the lower extremity gait pattern. The results suggest that gait parameters tend to shift towards a normal value pattern; and the re-establishment of pre-injury gait patterns-including the normal biphase of muscles-takes at least 8 months to occur.

  16. Effects of ACL Reconstructive Surgery on Temporal Variations of Cytokine Levels in Synovial Fluid.

    PubMed

    Bigoni, Marco; Turati, Marco; Gandolla, Marta; Sacerdote, Paola; Piatti, Massimiliano; Castelnuovo, Alberto; Franchi, Silvia; Gorla, Massimo; Munegato, Daniele; Gaddi, Diego; Pedrocchi, Alessandra; Omeljaniuk, Robert J; Locatelli, Vittorio; Torsello, Antonio

    2016-01-01

    Anterior cruciate ligament (ACL) reconstruction restores knee stability but does not reduce the incidence of posttraumatic osteoarthritis induced by inflammatory cytokines. The aim of this research was to longitudinally measure IL-1β, IL-6, IL-8, IL-10, and TNF-α levels in patients subjected to ACL reconstruction using bone-patellar tendon-bone graft. Synovial fluid was collected within 24-72 hours of ACL rupture (acute), 1 month after injury immediately prior to surgery (presurgery), and 1 month thereafter (postsurgery). For comparison, a "control" group consisted of individuals presenting chronic ACL tears. Our results indicate that levels of IL-6, IL-8, and IL-10 vary significantly over time in reconstruction patients. In the acute phase, the levels of these cytokines in reconstruction patients were significantly greater than those in controls. In the presurgery phase, cytokine levels in reconstruction patients were reduced and comparable with those in controls. Finally, cytokine levels increased again with respect to control group in the postsurgery phase. The levels of IL-1β and TNF-α showed no temporal variation. Our data show that the history of an ACL injury, including trauma and reconstruction, has a significant impact on levels of IL-6, IL-8, and IL-10 in synovial fluid but does not affect levels of TNF-α and IL-1β. PMID:27313403

  17. Effects of ACL Reconstructive Surgery on Temporal Variations of Cytokine Levels in Synovial Fluid

    PubMed Central

    Bigoni, Marco; Gandolla, Marta; Sacerdote, Paola; Piatti, Massimiliano; Castelnuovo, Alberto; Franchi, Silvia; Gorla, Massimo; Munegato, Daniele; Gaddi, Diego; Pedrocchi, Alessandra; Omeljaniuk, Robert J.; Locatelli, Vittorio; Torsello, Antonio

    2016-01-01

    Anterior cruciate ligament (ACL) reconstruction restores knee stability but does not reduce the incidence of posttraumatic osteoarthritis induced by inflammatory cytokines. The aim of this research was to longitudinally measure IL-1β, IL-6, IL-8, IL-10, and TNF-α levels in patients subjected to ACL reconstruction using bone-patellar tendon-bone graft. Synovial fluid was collected within 24–72 hours of ACL rupture (acute), 1 month after injury immediately prior to surgery (presurgery), and 1 month thereafter (postsurgery). For comparison, a “control” group consisted of individuals presenting chronic ACL tears. Our results indicate that levels of IL-6, IL-8, and IL-10 vary significantly over time in reconstruction patients. In the acute phase, the levels of these cytokines in reconstruction patients were significantly greater than those in controls. In the presurgery phase, cytokine levels in reconstruction patients were reduced and comparable with those in controls. Finally, cytokine levels increased again with respect to control group in the postsurgery phase. The levels of IL-1β and TNF-α showed no temporal variation. Our data show that the history of an ACL injury, including trauma and reconstruction, has a significant impact on levels of IL-6, IL-8, and IL-10 in synovial fluid but does not affect levels of TNF-α and IL-1β. PMID:27313403

  18. Differences in Mechanisms of Failure, Intraoperative Findings, and Surgical Characteristics Between Single- and Multiple-Revision ACL Reconstructions

    PubMed Central

    Chen, James L.; Allen, Christina R.; Stephens, Thomas E.; Haas, Amanda K.; Huston, Laura J.; Wright, Rick W.; Feeley, Brian T.

    2013-01-01

    Background The factors that lead to patients failing multiple anterior cruciate ligament (ACL) reconstructions are not well understood. Hypothesis Multiple-revision ACL reconstruction will have different characteristics than first-time revision in terms of previous and current graft selection, mode of failure, chondral/meniscal injuries, and surgical charactieristics. Study Design Case-control study; Level of evidence, 3. Methods A prospective multicenter ACL revision database was utilized for the time period from March 2006 to June 2011. Patients were divided into those who underwent a single-revision ACL reconstruction and those who underwent multiple-revision ACL reconstructions. The primary outcome variable was Marx activity level. Primary data analyses between the groups included a comparison of graft type, perceived mechanism of failure, associated injury (meniscus, ligament, and cartilage), reconstruction type, and tunnel position. Data were compared by analysis of variance with a post hoc Tukey test. Results A total of 1200 patients (58% men; median age, 26 years) were enrolled, with 1049 (87%) patients having a primary revision and 151 (13%) patients having a second or subsequent revision. Marx activity levels were significantly higher (9.77) in the primary-revision group than in those patients with multiple revisions (6.74). The most common cause of reruptures was a traumatic, noncontact ACL graft injury in 55% of primary-revision patients; 25% of patients had a nontraumatic, gradual-onset recurrent injury, and 11% had a traumatic, contact injury. In the multiple-revision group, a nontraumatic, gradual-onset injury was the most common cause of recurrence (47%), followed by traumatic noncontact (35%) and nontraumatic sudden onset (11%) (P < .01 between groups). Chondral injuries in the medial compartment were significantly more common in the multiple-revision group than in the single-revision group, as were chondral injuries in the patellofemoral

  19. Comparison of the postural control between football players following ACL reconstruction and healthy subjects

    PubMed Central

    Pahnabi, Gholamreza; Akbari, Mohammad; Ansari, Noureddin Nakhostin; Mardani, Mahmoud; Ahmadi, Mehdi; Rostami, Mohamad

    2014-01-01

    Background: Rupture of the Anterior Cruciate Ligment (ACL) is a common knee injury. The purpose of this study was to determine the balance control in football players with and without ACL reconstruction in posture of injury. Methods: Sway of the center of gravity of 15 patients with ACL reconstruction was compared with 15 healthy, age and sex-matched subjects as the control group. All tests were done unilaterally in the posture of injury, using a kistler force plate with the open and -closed eye conditions. Results: The knee of the operated side of the case group showed more displacement of the center of gravity when compared to the non-operated side in the same subject for all variables of the force plate. The operated side of the case group showed more displacement of the center of gravity for all variables of the force plate in comparison with the dominant side of knees in control group. There were significant differences between the non-operated side in the case group and the dominant side of the control group. Conclusion: All together, postural control in the operated side of the case group was weaker than the nonoperated side of the same group and the dominant limb of the control group, which might have resulted from poor proprioception. The postural control was even weaker in the non-operated side of the case group as compared with the dominant limb of the control group, which can justify the hypo mobility of limb for several months after the surgery. PMID:25664302

  20. Postinfectious ankylosis of the knee after bacterial arthritis following routine anterior cruciate ligament (ACL) reconstruction

    PubMed Central

    Mester, Bastian; Schoepp, Christian; Glombitza, Martin; Rixen, Dieter

    2016-01-01

    Aims and Objectives: Knee arthroscopy is a very common surgical procedure. It belongs to the most frequently performed procedures in orthopedics and traumatology and is considered to have a low complication rate. The risk of postoperative knee infection following ACL reconstrucion is estimated 1-2 %. Thereby the ACL reconstruction cannot always be preserved. Persistent defects after healing and postinfectios osteoarthritis are observed. We present the case of an adolescent patient suffering from postoperative knee infection following routine ACL reconstruction, who is developing - while infection is decreasing - a complete bony ankylosis of the knee, clinically meaning a severe constraint to joint function with complete stiffness of the knee. Materials and Methods: The 13-year-old male patient sustained a distorsion of the right knee during sports at school, after clinical examination magnetic resonance tomography showed a complete tear of the ACL. Single bundle ACL reconstruction was done using autologous hamstrings in Transfix technique. After 5 days at hospital the patient was discharged without any complications. Shortly afterwards the patient was admitted to hospital again presenting a postoperative knee infection. After primary operative revision the patient was shifted to our intensive care unit in a septic condition for stabilization. During 4 month of stay at our hospital multiple operative revisions were performed as arthrotomy, debridement, insertion of antibiotic carriers, complete removal of the autograft and total synovectomy. We found a severe bacterial infection (staphylococcus aureus) of the knee joint, classified Gaechter IV, histopathologically mostly avital cartilage tissue and chronic synovialitis. After decrease of the infection we could discharge the patient from hospital. Results: During the following 8 month under ongoing physiotherapy the patient was developing an increasing stiffness of the knee, finally fixed at 30 degrees of flexion and

  1. Stress fractures of the femur after ACL reconstruction with transfemoral fixation.

    PubMed

    Arriaza, Rafael; Señaris, Jose; Couceiro, Gonzalo; Aizpurua, Jesus

    2006-11-01

    The ACL reconstruction with hamstring tendons has become increasingly popular, in part because it is assumed that the complication rate associated with the technique and their severity are lower than with patellar tendon. Two cases of stress reaction of the medial supracondylar area of the femur after ACL reconstruction with hamstring tendons using BioTransfix (Arthrex, Naples, FL, USA) devices for fixation within femur are presented. Both patients were professional athletes (one soccer and one basketball player), and it is hypothesized that the accelerated rehabilitation program used might have represented a risk factor for stress fractures when associated with the guide pin exit hole in the medial femoral cortex. To our knowledge, no such cases have been published to date, but it is important to consider this possibility if an unexplained pain arises in the rehabilitation process of an ACL reconstruction using transfemoral fixation.

  2. Extra-articular extraosseous migration of a bioabsorbable femoral interference screw after ACL reconstruction.

    PubMed

    Sharma, Vivek; Curtis, Christine; Micheli, Lyle

    2008-10-01

    Anterior cruciate ligament (ACL) reconstruction is quite commonly used to treat anterior knee instability. Surgeon preference and patient functional goals determine graft selection and graft fixation techniques. Interference screws are considered a safe and effective device for graft fixation in surgical ACL reconstruction. Poly-L-lactide acid (PLLA) bioabsorbable interference screws are becoming increasingly popular in ACL reconstruction surgery. There are several reasons why they may be more advantageous than metallic screws, including reduced graft laceration during insertion, ease of performance of revision procedures, avoidance of graft injury encountered with aperture fixation using metallic screws, and fewer artifacts on magnetic resonance images (MRI). Few studies describe complications associated with PLLA bioabsorbable screws, particularly extra-articular screw migration. This article presents a case of an extra-articular extraosseous migration of the femoral bioabsorbable interference screw. This case further demonstrates the problem of the femoral bioabsorbable interference screw.

  3. Avoiding Complications and Technical Variability During Arthroscopically Assisted Transtibial ACL Reconstructions by Using a C-Arm With Image Intensifier

    PubMed Central

    Trentacosta, Natasha; Fillar, Allison Liefeld; Liefeld, Cynthia Pierce; Hossack, Michael D.; Levy, I. Martin

    2014-01-01

    Background: Surgical reconstruction of the anterior cruciate ligament (ACL) can be complicated by incorrect and variable tunnel placement, graft tunnel mismatch, cortical breaches, and inadequate fixation due to screw divergence. This is the first report describing the use of a C-arm with image intensifier employed for the sole purpose of eliminating those complications during transtibial ACL reconstruction. Purpose: To determine if the use of a C-arm with image intensifier during arthroscopically assisted transtibial ACL reconstruction (IIAA-TACLR) eliminated common complications associated with bone–patellar tendon–bone ACL reconstruction, including screw divergence, cortical breaches, graft-tunnel mismatch, and improper positioning of the femoral and tibial tunnels. Study Design: Case series; Level of evidence, 4. Methods: A total of 110 consecutive patients (112 reconstructed knees) underwent identical IIAA-TACLR using a bone–patellar tendon–bone autograft performed by a single surgeon. Intra- and postoperative radiographic images and operative reports were evaluated for each patient looking for evidence of cortical breeching and screw divergence. Precision of femoral tunnel placement was evaluated using a sector map modified from Bernard et al. Graft recession distance and tibial α angles were recorded. Results: There were no femoral or tibial cortical breaches noted intraoperatively or on postoperative images. There were no instances of loss of fixation screw major thread engagement. There were no instances of graft-tunnel mismatch. The positions of the femoral tunnels were accurate and precise, falling into the desired sector of our location map (sector 1). Tibial α angles and graft recession distances varied widely. Conclusion: The use of the C-arm with image intensifier enabled accurate and precise tunnel placement and completely eliminated cortical breach, graft-tunnel mismatch, and screw divergence during IIAA-TACLR by allowing incremental

  4. Transverse femoral implant prominence: four cases demonstrating a preventable complication for ACL reconstruction.

    PubMed

    Argintar, Evan; Scherer, Benjamin; Jordan, Tom; Klimkiewicz, John

    2010-12-01

    Anterior cruciate ligament (ACL) tear is a commonly occurring injury that often demands surgical reconstruction. Although the utility of this operation is widely accepted, many specific components, including graft fixation technique, remain controversial. Many clinicians favor transverse femoral implant fixation for soft tissue ACL grafts. This technique can be accomplished successfully; however, in a minority of the cases, the femoral implant can be excessively prominent, leading to iatrogenic postoperative iliotibial band syndrome. This article presents 4 patients that developed postoperative iliotibial band syndrome resulting from transverse femoral implant prominence. Despite achievement of knee ligamentous stability, implant prominence compromised final clinical results following ACL reconstruction. Through change in Lysholm value, we reviewed the clinical outcomes of these patients following femoral implant hardware removal for treatment of iliotibial band syndrome. On hardware removal, all patients demonstrated complete symptomatic improvement, mirroring an average Lysholm value increase of 38. We believe transverse femoral implant prominence is avoidable, and subsequent iliotibial band syndrome is a preventable postoperative complication.

  5. Perturbation training prior to ACL reconstruction improves gait asymmetries in non-copers.

    PubMed

    Hartigan, Erin; Axe, Michael J; Snyder-Mackler, Lynn

    2009-06-01

    We investigated whether preoperative perturbation training would help anterior cruciate ligament (ACL) deficient individuals who complain of knee instability ("non-copers") regain quadriceps strength and walk normally after ACL reconstruction. Nineteen non-copers with acute ACL injury were randomly assigned into a perturbation group (PERT) or a strengthening group (STR). The PERT group received specialized neuromuscular training and progressive quadriceps strength training, whereas the STR group received progressive quadriceps strength training only. We compared quadriceps strength indexes and knee excursions during the mid-stance phase of gait preoperatively to data collected 6 months after ACL reconstruction. Analyses of Variance with repeated measures (time/limb) were conducted to compare quadriceps strength index values over time (time x group) and differences in knee excursions in limbs between groups over time (limb x time x group). If significance was found, post hoc analyses were performed using paired and independent t-tests. Quadriceps strength indexes before intervention (Pert: 87.2%; Str: 75.8%) improved 6 months after ACL reconstruction in both groups (Pert: 97.1%; Str: 94.4%). Non-copers who received perturbation training preoperatively had no differences in knee excursions between their limbs 6 months after ACL reconstruction (p = 0.14), whereas those who received just strength training continued to have smaller knee excursions during the mid-stance phase of gait (p = 0.007). Non-copers strength and knee excursions were more symmetrical 6 months postoperatively in the group that received perturbation training and progressive quadriceps strength training than the group who received strength training alone.

  6. High intensity running results in an impaired neuromuscular response in ACL reconstructed individuals.

    PubMed

    Patras, Kostas; Ziogas, Giorgos; Ristanis, Stavros; Tsepis, Elias; Stergiou, Nicholas; Georgoulis, Anastasios D

    2009-08-01

    Anterior cruciate ligament (ACL) reconstruction reestablishes electromyographic activity during moderate activities such as walking but is unclear if this is also the case in sports activities such as high intensity running that results in accumulation of metabolic fatigue. Nine bone-patella tendon-bone ACL reconstructed athletes were evaluated 19.2 (5.7) months post-operatively using a telemetric electromyographic system. The neuromuscular response of vastus lateralis and biceps femoris muscles was tested bilaterally on separate occasions during 10 min running at moderate intensity (20% below the lactate threshold) and 10 min running at high intensity (40% above the lactate threshold). During moderate intensity running, electromyographic activity did not change for either leg. During high intensity running, electromyographic activity did not change for the vastus lateralis of the ACL reconstructed leg [267.8 (142.8)-263.8 (128.9) microV, P > 0.05] while it increased significantly [294.2 (120.6)-317.1 (140.5) microV, P = 0.03] for the vastus lateralis of the intact leg. High intensity exercise that is associated with accumulation of metabolic fatigue, results in an impaired neuromuscular response for the vastus lateralis muscle of the ACL reconstructed leg.

  7. In vivo analysis of the pivot shift phenomenon during computer navigated ACL reconstruction.

    PubMed

    Lane, Clayton G; Warren, Russell F; Stanford, Fatima C; Kendoff, Daniel; Pearle, Andrew D

    2008-05-01

    ACL insufficiency can be documented clinically with the pivot shift maneuver, but the specific pathologic kinematics of the pivot shift is difficult to quantify. Navigation provides an opportunity to analyze in vivo the motions that comprise the pivot shift and the kinematic changes that are inherent after ACL reconstruction. We hypothesized that tibial rotation, anterior tibial translation (ATT), acceleration of posterior translation (APT) and the newly described angle of P, quantified during navigated pivot shift examination, correlate with clinical grading of the pivot shift phenomena. Navigation data from 12 patients who underwent navigated ACL surgery were retrospectively reviewed. A characteristic P-shaped track of motion is recorded by the navigation software during the pivot-shift examination. The "angle of P" was developed as a means characterizing this track of motion and was measured in all cases. The tibial rotation, maximum anterior tibial translation and acceleration of posterior translation during the pivot shift were also measured. The charts of these patients were reviewed to obtain information on the clinical grading of the pivot-shift before and after ACL reconstruction. Spearman correlation analysis was then used to identify significant correlations between clinical grade of the pivot shift and the angle of p measured with computer navigation. After reconstruction, the clinical grade of the pivot shift was zero in all patients. The tibial rotation, maximum ATT, APT and the angle of p also decreased. On analysis of 24 EUAs, 12 before reconstruction and 12 after, there was excellent and significant correlation between the clinical grade of pivot shift examination and the angle of P (R2 = 0.97, p < 0.001). Only good correlation was noted between the clinical pivot shift and the rotation (R2 = 0.77, p < 0.0001), maximum ATT (R2 = 0.87, p < 0.0001) and APT (R2 = 0.81, p < 0.0001). There was a stepwise increase of 6-7 mm of translation and 5-6 degrees

  8. Effect of 12 Weeks of Accelerated Rehabilitation Exercise on Muscle Function of Patients with ACL Reconstruction of the Knee Joint.

    PubMed

    Lee, Joong-Chul; Kim, Ji Youn; Park, Gi Duck

    2013-12-01

    [Purpose] To examine changes in the knee joint's isokinetic muscle functions following systematic and gradual rehabilitation exercises lasting for 12 weeks for male and female patients who underwent anterior cruciate ligament (ACL) reconstruction. Differences in muscle functions between the uninvolved side (US) and the involved side (IS) before surgery, differences in muscle functions between US and IS after rehabilitation exercises lasting for 12 weeks, and changes in muscle functions on US and IS between before and after surgery were analyzed to examine the effects of accelerated rehabilitation exercises after ACL reconstruction. [Subjects] The study subjects were 10 patients, five females and five males, who underwent ACL reconstruction performed by the same surgeon. [Methods] As a measuring tool, a Biodex Multi-joint system 3pro (USA), which is an isokinetic measuring device, was used to examine the flexion and extension forces of the knee joint. During isokinetic muscle strength evaluation, the ROM of US was set to be the same as that of IS for consistency of measurement. [Results] At 60°/s, the isokinetic muscle functions of the females did not show any significant change between before and after surgery in any of the variables on both US and IS. At 60°/s, the isokinetic muscle functions of the males did not show any significant change between before and after surgery in the peak torque, average power, and entire work done on US. In extension, peak torque on IS did not show any significant change.

  9. Knee functional recovery and limb-to-limb symmetry restoration after anterior cruciate ligament (ACL) rupture and ACL reconstruction

    NASA Astrophysics Data System (ADS)

    Nawasreh, Zakariya Hussein

    Anterior cruciate ligament (ACL) rupture is a common sport injury of young athletes who participate in jumping, cutting, and pivoting activities. Although ACL reconstruction (ACLR) surgery has the goal of enabling athletes to return to preinjury activity levels, treatment results often fall short of this goal. The outcomes after ACLR are variable and less than optimal with low rate of return to preinjury activity level and high risk for second ACL injury. Factors related to the knee functional limitations, strength deficits, and limb-to-limb movement asymmetry may be associated with poor outcomes after ACLR. Additionally, the criteria that are used to determine a patient's readiness to return to the preinjury activity level are undefined which may also be associated with poor outcomes after ACLR. The clinical decision-making to clear patients' for safe and successful return to high physical activities should be based on a universal comprehensive set of objective criteria that ensure normal knee function and limb-to-limb symmetry. A battery of return to activity criteria (RTAC) that emphases normal knee function and limb-to-limb movement symmetry has been constituted to better ensure safe and successful return to preinjury activity level. Yet, only variables related to patients' demographics, concomitant injuries, and treatment measures have been used to predict return to preinjury activity levels after ACLR. However, the ability of RTAC variables that ensure normal knee function and limb movement symmetry to predict the return to participate in the same preinjury activity level after ACLR has not been investigated. In light of this background, the first aim of the present study was to compare functional knee performance-based and patient-reported measures of those who PASS and who FAIL on RTAC at 6 months (6-M) following ACLR with those at 12 months (12-M) and 24 months (24-M) following ACLR and to determine how performance-based and patient-reported measures

  10. Single-Bundle Anterior Cruciate Ligament Reconstruction with Semitendinosus Tendon Using the PINN-ACL CrossPin System: Minimum 4-Year Follow-up

    PubMed Central

    Baek, Seung-Gil; Lee, Byoung-Joo; Lee, Chang-Hwa

    2015-01-01

    Purpose This study evaluated mid-term results of anterior cruciate ligament (ACL) reconstruction using the PINN-ACL CrossPin system that allowed for short graft fixation. Materials and Methods Forty-three patients underwent single-bundle ACL reconstruction with a 4-strand semitendinosus tendon graft using the PINN-ACL CrossPin system. Femoral fixation was done using the PINN-ACL CrossPin system, and the tibial side was fixed with post-tie and a bioabsorbable interference screw. The mean follow-up period was 50 months. Evaluation was done using the Lachman test, pivot-shift test, International Knee Documentation Committee (IKDC) score and grade. Anterior displacement was assessed. Results There was improvement in the Lachman test and pivot-shift test at final follow-up, form grade II (n=40) or III (n=3) to grade I (n=3) or 0 (n=40) and from grade I (n=20) or II (n=10) to grade I (n=8) or 0 (n=22), respectively. The mean IKDC score was 88.7, and grade A and B were 93.0% at final follow-up. Side-to-side difference was improved from 6.7 mm to 2.1 mm at final follow-up. Complications occurred in 3 patients, a re-ruptured due to trauma at 2 years after surgery and a deep infection and a superficial infection. Conclusions The mid-term follow-up results of ACL reconstruction with the PINN-ACL CrossPin system were satisfactory. The PINN-ACL CrossPin can be considered as a useful instrument for short graft fixation. PMID:25750893

  11. Comparison of volumetric bone mineral density in the tibial region of interest for ACL reconstruction.

    PubMed

    Klein, Scott A; Nyland, John; Caborn, David N M; Kocabey, Yavuz; Nawab, Akbar

    2005-12-01

    Adequate tibial bone mineral density (BMD) is essential to soft tissue graft fixation during anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to compare volumetric bone plug density measurements at the tibial region of interest for ACL reconstruction using a standardized immersion technique and Archimedes' principle. Cancellous bone cores were harvested from the proximal, middle, and distal metaphyseal regions of the lateral tibia and from the standard tibial tunnel location used for ACL reconstruction of 18 cadaveric specimens. Proximal tibial cores displayed 32.6% greater BMD than middle tibial cores and 31.8% greater BMD than distal tibial cores, but did not differ from the BMD of the tibial tunnel cores. Correlational analysis confirmed that the cancellous BMD in the tibial tunnel related to the cancellous BMD of the proximal and distal lateral tibial metaphysis. In conjunction with its adjacent cortical bone, the cancellous BMD of the region used for standard tibial tunnel placement provides an effective foundation for ACL graft fixation. In tibia with poor BMD, bicortical fixation that incorporates cortical bone from the distal tibial tunnel region is recommended. PMID:16237489

  12. Knee functional recovery and limb-to-limb symmetry restoration after anterior cruciate ligament (ACL) rupture and ACL reconstruction

    NASA Astrophysics Data System (ADS)

    Nawasreh, Zakariya Hussein

    Anterior cruciate ligament (ACL) rupture is a common sport injury of young athletes who participate in jumping, cutting, and pivoting activities. Although ACL reconstruction (ACLR) surgery has the goal of enabling athletes to return to preinjury activity levels, treatment results often fall short of this goal. The outcomes after ACLR are variable and less than optimal with low rate of return to preinjury activity level and high risk for second ACL injury. Factors related to the knee functional limitations, strength deficits, and limb-to-limb movement asymmetry may be associated with poor outcomes after ACLR. Additionally, the criteria that are used to determine a patient's readiness to return to the preinjury activity level are undefined which may also be associated with poor outcomes after ACLR. The clinical decision-making to clear patients' for safe and successful return to high physical activities should be based on a universal comprehensive set of objective criteria that ensure normal knee function and limb-to-limb symmetry. A battery of return to activity criteria (RTAC) that emphases normal knee function and limb-to-limb movement symmetry has been constituted to better ensure safe and successful return to preinjury activity level. Yet, only variables related to patients' demographics, concomitant injuries, and treatment measures have been used to predict return to preinjury activity levels after ACLR. However, the ability of RTAC variables that ensure normal knee function and limb movement symmetry to predict the return to participate in the same preinjury activity level after ACLR has not been investigated. In light of this background, the first aim of the present study was to compare functional knee performance-based and patient-reported measures of those who PASS and who FAIL on RTAC at 6 months (6-M) following ACLR with those at 12 months (12-M) and 24 months (24-M) following ACLR and to determine how performance-based and patient-reported measures

  13. ALL‐EPIPHYSEAL ACL RECONSTRUCTION: A THREE‐YEAR FOLLOW‐UP

    PubMed Central

    Akinleye, Sheriff D.; Sewick, Amy

    2013-01-01

    Background/Introduction: With an increasing number of pre‐adolescents participating in sports, anterior cruciate ligament injuries and resultant reconstruction in the skeletally immature athlete are becoming more common. Many different surgical techniques and rehabilitation protocols have been proposed for the treatment of anterior cruciate ligament (ACL) injuries, but there is a lack of agreement as to which approach results in the best outcome. Rehabilitation protocols have marked variation regarding postoperative weight bearing, immobilization, bracing, and length. Case description: This is a case of a ten year old female who sustained bilateral ACL tears within the period of a year. The purpose of this case report is to describe the early result and subsequent rehabilitation following bilateral physeal‐sparing all‐epiphyseal ACL reconstructions on a skeletally immature patient with a three‐year follow‐up. Outcomes: The early post‐surgical recovery period on the first injured knee was complicated by knee stiffness requiring manipulation. Following this minor setback, the patient met all physical therapy goals and had no additional complications. The rehabilitation after the second surgery followed a typical course. At three‐year follow‐up, the patient had grown an additional seven inches, with radiographic evidence of symmetric physeal growth and joint stability. She has returned to playing competitive sports. Discussion and Conclusion: This innovative physeal‐sparing technique has huge implications as, historically; the feared complication of growth disturbance and angular deformity from transphyseal ACL reconstruction has complicated the management of ACL injuries in children and pre‐adolescents. This case report demonstrates the success of this technique, and the subsequent rehabilitation, as this patient did not experience a reduction in long‐term bone growth. Level of Evidence: 5 Case Report PMID:23772346

  14. Persistent Biomechanical Alterations After ACL Reconstruction Are Associated With Early Cartilage Matrix Changes Detected by Quantitative MR

    PubMed Central

    Amano, Keiko; Pedoia, Valentina; Su, Favian; Souza, Richard B.; Li, Xiaojuan; Ma, C. Benjamin

    2016-01-01

    Background: The effectiveness of anterior cruciate ligament (ACL) reconstruction in preventing early osteoarthritis is debated. Restoring the original biomechanics may potentially prevent degeneration, but apparent pathomechanisms have yet to be described. Newer quantitative magnetic resonance (qMR) imaging techniques, specifically T1ρ and T2, offer novel, noninvasive methods of visualizing and quantifying early cartilage degeneration. Purpose: To determine the tibiofemoral biomechanical alterations before and after ACL reconstruction using magnetic resonance imaging (MRI) and to evaluate the association between biomechanics and cartilage degeneration using T1ρ and T2. Study Design: Cohort study; Level of evidence, 2. Methods: Knee MRIs of 51 individuals (mean age, 29.5 ± 8.4 years) with unilateral ACL injuries were obtained prior to surgery; 19 control subjects (mean age, 30.7 ± 5.3 years) were also scanned. Follow-up MRIs were obtained at 6 months and 1 year. Tibial position (TP), internal tibial rotation (ITR), and T1ρ and T2 were calculated using an in-house Matlab program. Student t tests, repeated measures, and regression models were used to compare differences between injured and uninjured sides, observe longitudinal changes, and evaluate correlations between TP, ITR, and T1ρ and T2. Results: TP was significantly more anterior on the injured side at all time points (P < .001). ITR was significantly increased on the injured side prior to surgery (P = .033). At 1 year, a more anterior TP was associated with elevated T1ρ (P = .002) and T2 (P = .026) in the posterolateral tibia and with decreased T2 in the central lateral femur (P = .048); ITR was associated with increased T1ρ in the posteromedial femur (P = .009). ITR at 6 months was associated with increased T1ρ at 1 year in the posteromedial tibia (P = .029). Conclusion: Persistent biomechanical alterations after ACL reconstruction are related to significant changes in cartilage T1ρ and T2 at 1 year

  15. Which one Enhances Muscular Performance in ACL Reconstructed Subjects

    PubMed Central

    Harput, Gulcan; Ulusoy, Burak; Atay, Ahmet Ozgur; Baltacı, Gul

    2014-01-01

    Objectives: The aim of this study was to investigate the effects of functional knee brace and kinesiotaping on muscular performance in anterior cruciate ligament reconstructed subjects who reached return to sport phase of the rehabilitation. Methods: Twenty (17 males, 3 females, Age: 24.7±7.1 years, Body weight: 74.4±12.0 kg, Height: 177.9±6.5 cm, BMI: 23.9±3.6 kg/m2) subjects who underwent anterior cruciate ligament reconstruction by using hamstring tendon auto graft were included in this study. When the subjects reached the return to sports phase of rehabilitation which was 6th months after surgery, knee muscle strength, jump performance and balance tests were performed 3 times: bare, with knee brace and with kinesio taping. The order of the tests were randomized to eliminate the effects of fatigue and motor learning. Quadriceps and hamstring muscle strength was measured on an isokinetic dynamometer at 180 °/s and 60°/s angular velocities. Vertical Jump (VJ) and One Leg Hop Tests (OLHT) were used to assess jump performance. Star Excursion Balance Test (SEBT) with anterior, posteromedial and posterolateral reach distance was used to assess the dynamic balance. When all tests were performed, the subjects were asked under which test condition they felt more confident. Repeated measures of ANOVA was used to analyze the difference among three test conditions (bare, kinesiotaping, knee brace). Bonferroni post hoc test was used for pairwise comparison. Results: SEBT posteromedial (PM)and posterolateral (PL) reach distances were found significantly different among three test conditions(PM: F(2,38)=3.42,p=0.04), PL: F(2,38)=4.37,p=0.02). Kinesiotaping increased posteromedial reach distance (p=0.03). On the other hand, brace decreased posterolateral reach distance (p=0.04). VJ and OLHT performance were also found significantly different between three test conditions (VJ: F (2,38)=3.44,p=0.04, OLHT: (F(2,38)=4.04,p=0.02). Kinesio taping increased one leg hop distance

  16. Pre-operative factors predicting good outcome in terms of health-related quality of life after ACL reconstruction.

    PubMed

    Månsson, O; Kartus, J; Sernert, N

    2013-02-01

    The life situation of many patients changes after an anterior cruciate ligament (ACL) rupture and subsequent reconstruction, and this may affect their health-related quality of life in many ways. It is well known that the overall clinical results after ACL reconstruction are considered good, but pre-operative predictive factors for a good post-operative clinical outcome after ACL reconstruction have not been studied in as much detail. The purpose of this study was to identify pre-operative factors that predict a good post-operative outcome as measured by the Short Form 36 (SF-36) and Knee Osteoarthritis Outcome Score (KOOS) 3-6 years after ACL reconstruction. Seventy-three patients scheduled for ACL reconstruction were clinically examined pre-operatively. The SF-36 and KOOS questionnaires were sent by mail to these patients 3-6 years after reconstruction. Predictive factors for health-related quality of life were investigated using a stepwise regression analysis. In conclusion, pre-operative factors, such as pivot shift, knee function, and range of motion, may predict a good post-operative outcome and explain up to 25% in terms of health-related quality of life after ACL reconstruction. Furthermore, it appears that the patients' pre-injury and pre-operative Tegner activity levels are important predictors of post-operative health-related quality of life.

  17. Use of ultra-high molecular weight polycaprolactone scaffolds for ACL reconstruction.

    PubMed

    Leong, Natalie L; Kabir, Nima; Arshi, Armin; Nazemi, Azadeh; Jiang, Jie; Wu, Ben M; Petrigliano, Frank A; McAllister, David R

    2016-05-01

    Previously, we reported on the implantation of electrospun polycaprolactone (PCL) grafts for use in ACL tissue engineering in a small animal model. In the present study, we hypothesized that grafts fabricated from ultra-high molecular weight polycaprolactone (UHMWPCL) would have similarly favorable biologic properties but superior mechanical properties as compared to grafts fabricated from PCL. Two forms of polycaprolactone were obtained (UHMWPCL, MW = 500 kD, and PCL, MW = 80 kD) and electrospun into scaffolds that were used to perform ACL reconstruction in 7-8 week old male Lewis rats. The following groups were examined: UHMWPCL, PCL, flexor digitorum longus (FDL) allograft, native ACL, as well as sham surgery in which the ACL was transsected. At 16 weeks post-operatively, biomechanical testing, histology, and immunohistochemistry (IHC) were performed. Analysis of cellularity indicated that there was no significant difference among the UHMWPCL, PCL, and FDL allograft groups. Quantification of birefringence from picrosirius red staining demonstrated significantly more aligned collagen fibers in the allograft than the PCL group, but no difference between the UHMWPCL and allograft groups. The peak load to failure of the UHMWPCL grafts was significantly higher than PCL, and not significantly different from FDL allograft. This in vivo study establishes the superiority of the higher molecular weight version of polycaprolactone over PCL as a scaffold material for ACL reconstruction. By 16 weeks after implantation, the UHMWPCL grafts were not significantly different from the FDL allografts in terms of cellularity, peak load to failure, stiffness, and collagen fiber alignment. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:828-835, 2016. PMID:26497133

  18. Giant Cell Tumor within the Proximal Tibia after ACL Reconstruction.

    PubMed

    Takahashi, Takashi; MacCormick, Lauren; Ellermann, Jutta; Clohisy, Denis; Marette, Shelly

    2016-01-01

    26-year-old female with prior anterior cruciate ligament reconstruction developed an enlarging lytic bone lesion around the tibial screw with sequential imaging over the course of one year demonstrating progression of this finding, which was confirmed histologically to be a giant cell tumor of bone. The lesion originated around the postoperative bed, making the diagnosis challenging during the early course of the presentation. The case demonstrates giant cell tumor which originated in the metaphysis and subsequently grew to involve the epiphysis; therefore, early course of the disease not involving the epiphysis should not exclude this diagnosis. PMID:26981302

  19. Giant Cell Tumor within the Proximal Tibia after ACL Reconstruction

    PubMed Central

    Takahashi, Takashi; MacCormick, Lauren; Ellermann, Jutta; Clohisy, Denis; Marette, Shelly

    2016-01-01

    26-year-old female with prior anterior cruciate ligament reconstruction developed an enlarging lytic bone lesion around the tibial screw with sequential imaging over the course of one year demonstrating progression of this finding, which was confirmed histologically to be a giant cell tumor of bone. The lesion originated around the postoperative bed, making the diagnosis challenging during the early course of the presentation. The case demonstrates giant cell tumor which originated in the metaphysis and subsequently grew to involve the epiphysis; therefore, early course of the disease not involving the epiphysis should not exclude this diagnosis. PMID:26981302

  20. Adverse effect of femoral nerve blockade on quadriceps strength and function after ACL reconstruction.

    PubMed

    Krych, Aaron; Arutyunyan, Grigoriy; Kuzma, Scott; Levy, Bruce; Dahm, Diane; Stuart, Michael

    2015-02-01

    The purpose of this study was to determine if quadriceps strength and functional outcomes were similar at 6 months following anterior cruciate ligament [ACL] reconstruction in patients receiving a continuous 48-hour femoral nerve blockade for postoperative analgesia (FNB group) versus patients with no FNB (control group). A retrospective cohort was designed including athletes who underwent primary ACL reconstruction with patellar tendon autograft between 2005 and 2010 at our institution with identical rehabilitation protocols. The FNB group included 96 patients with an average age of 21 years and the control group included 100 patients with an average age of 20 years. At 6 months following ACL reconstruction, isokinetic strength (slow and fast activation) and functional tests including vertical jump, single hop, triple hop, and return to sport were analyzed with an α value < 0.05 as significant. Multivariate regression models were used to compare these outcomes between the FNB and control groups after adjusting for gender and competitive athlete status. At 6 months, fast extension isokinetic strength was inferior in the FNB group (78 vs. 85%; p < 0.01). After adjusting for gender and competitive athlete status, fast (p = 0.002) and slow extension strength (p = 0.01), vertical jump (p = 0.03) and single jump (p = 0.02) were also inferior in the FNB group. There were no significant differences in full return to sport between the two groups (86% at 7.5 months in the FNB group vs. 93% at 7.3 months in the control group). In this retrospective comparative study, the hypothesis that patients treated with continuous FNB for postoperative analgesia following ACL reconstruction with patellar tendon autograft will have inferior knee extension (quadriceps) strength and function at 6 months follow-up was affirmed. However, no differences were observed in return to sport, bringing into question whether these statistical differences translate into

  1. Cross-cultural comparison of patients undergoing ACL reconstruction in the United States and Norway.

    PubMed

    Magnussen, Robert A; Granan, Lars-Petter; Dunn, Warren R; Amendola, Annunziato; Andrish, Jack T; Brophy, Robert; Carey, James L; Flanigan, David; Huston, Laura J; Jones, Morgan; Kaeding, Christopher C; McCarty, Eric C; Marx, Robert G; Matava, Matthew J; Parker, Richard D; Vidal, Armando; Wolcott, Michelle; Wolf, Brian R; Wright, Rick W; Spindler, Kurt P; Engebretsen, Lars

    2010-01-01

    Data from large prospectively collected anterior cruciate ligament (ACL) cohorts are being utilized to address clinical questions regarding ACL injury demographics and outcomes of ACL reconstruction. These data are affected by patient and injury factors as well as surgical factors associated with the site of data collection. The aim of this article is to compare primary ACL reconstruction data from patient cohorts in the United States and Norway, demonstrating the similarities and differences between two large cohorts. Primary ACL reconstruction data from the Multicenter Orthopaedic Outcomes Network (MOON) in the United States and the Norwegian National Knee Ligament Registry (NKLR) were compared to identify similarities and differences in patient demographics, activity at injury, preoperative Knee injury and Osteoarthritis Outcome Score (KOOS), time to reconstruction, intraarticular pathology, and graft choice. Seven hundred and thirteen patients from the MOON cohort were compared with 4,928 patients from the NKLR. A higher percentage of males (NKLR 57%, MOON 52%; P < 0.01) and increased patient age (NKLR 27 years, MOON 23 years; P\\0.001) were noted in the NKLR population. The most common sports associated with injury in the MOON cohort were basketball (20%), soccer (17%), and American football (14%); while soccer (42%), handball (26%), and downhill skiing (10%) were most common in the NKLR. Median time to reconstruction was 2.4 (Interquartile range [IQR] 1.2-7.2) months in the MOON cohort and 7.9 (IQR 4.2-17.8) months in the NKLR cohort (P < 0.001). Both meniscal tears (MOON 65%, NKLR 48%; P < 0.001) and articular cartilage defects (MOON 46%, NKLR 26%; P < 0.001) were more common in the MOON cohort. Hamstring autografts (MOON 44%, NKLR 63%) and patellar tendon autografts (MOON 42%, NKLR 37%) were commonly utilized in both cohorts. Allografts were much more frequently utilized in the MOON cohort (MOON 13%, NKLR 0.04%; P < 0.001). Significant diversity in patient

  2. The Effects of High-Intensity versus Low-Intensity Resistance Training on Leg Extensor Power and Recovery of Knee Function after ACL-Reconstruction

    PubMed Central

    Aue Sobol, Nanna; Andersen, Lars L.; Kiel, Peter; Løfholm, Peter; Magnusson, S. Peter; Krogsgaard, Michael R.

    2014-01-01

    Objective. Persistent weakness is a common problem after anterior cruciate ligament- (ACL-) reconstruction. This study investigated the effects of high-intensity (HRT) versus low-intensity (LRT) resistance training on leg extensor power and recovery of knee function after ACL-reconstruction. Methods. 31 males and 19 females were randomized to HRT (n = 24) or LRT (n = 26) from week 8–20 after ACL-reconstruction. Leg extensor power, joint laxity, and self-reported knee function were measured before and 7, 14, and 20 weeks after surgery. Hop tests were assessed before and after 20 weeks. Results. Power in the injured leg was 90% (95% CI 86–94%) of the noninjured leg, decreasing to 64% (95% CI 60–69%) 7 weeks after surgery. During the resistance training phase there was a significant group by time interaction for power (P = 0.020). Power was regained more with HRT compared to LRT at week 14 (84% versus 73% of noninjured leg, resp.; P = 0.027) and at week 20 (98% versus 83% of noninjured leg, resp.; P = 0.006) without adverse effects on joint laxity. No other between-group differences were found. Conclusion. High-intensity resistance training during rehabilitation after ACL-reconstruction can improve muscle power without adverse effects on joint laxity. PMID:24877078

  3. Assessing 3D tunnel position in ACL reconstruction using a novel single image 3D-2D registration

    NASA Astrophysics Data System (ADS)

    Kang, X.; Yau, W. P.; Otake, Y.; Cheung, P. Y. S.; Hu, Y.; Taylor, R. H.

    2012-02-01

    The routinely used procedure for evaluating tunnel positions following anterior cruciate ligament (ACL) reconstructions based on standard X-ray images is known to pose difficulties in terms of obtaining accurate measures, especially in providing three-dimensional tunnel positions. This is largely due to the variability in individual knee joint pose relative to X-ray plates. Accurate results were reported using postoperative CT. However, its extensive usage in clinical routine is hampered by its major requirement of having CT scans of individual patients, which is not available for most ACL reconstructions. These difficulties are addressed through the proposed method, which aligns a knee model to X-ray images using our novel single-image 3D-2D registration method and then estimates the 3D tunnel position. In the proposed method, the alignment is achieved by using a novel contour-based 3D-2D registration method wherein image contours are treated as a set of oriented points. However, instead of using some form of orientation weighting function and multiplying it with a distance function, we formulate the 3D-2D registration as a probability density estimation using a mixture of von Mises-Fisher-Gaussian (vMFG) distributions and solve it through an expectation maximization (EM) algorithm. Compared with the ground-truth established from postoperative CT, our registration method in an experiment using a plastic phantom showed accurate results with errors of (-0.43°+/-1.19°, 0.45°+/-2.17°, 0.23°+/-1.05°) and (0.03+/-0.55, -0.03+/-0.54, -2.73+/-1.64) mm. As for the entry point of the ACL tunnel, one of the key measurements, it was obtained with high accuracy of 0.53+/-0.30 mm distance errors.

  4. PATIENT-SPECIFIC AND SURGERY-SPECIFIC FACTORS THAT AFFECT RETURN TO SPORT AFTER ACL RECONSTRUCTION

    PubMed Central

    Lynch, Andrew; Rabuck, Stephen; Lynch, Brittany; Davin, Sarah; Irrgang, James

    2016-01-01

    Context Anterior cruciate ligament (ACL) reconstruction is frequently performed to allow individuals to return to their pre-injury levels of sports participation, however, return to pre-injury level of sport is poor and re-injury rates are unacceptably high. Re-injury is likely associated with the timeframe and guidelines for return to sport (RTS). It is imperative for clinicians to recognize risk factors for re-injury and to ensure that modifiable risk factors are addressed prior to RTS. The purpose of this commentary is to summarize the current literature on the outcomes following return to sport after ACL reconstruction and to outline the biologic and patient-specific factors that should be considered when counseling an athlete on their progression through rehabilitation. Evidence Acquisition A comprehensive literature search was performed to identify RTS criteria and RTS rates after ACL reconstruction with consideration paid to graft healing, anatomic reconstruction, and risk factors for re-injury and revision. Results were screened for relevant original research articles and review articles, from which results were summarized. Study Design Clinical Review of the Literature Results Variable RTS rates are presented in the literature due to variable definitions of RTS ranging from a high threshold (return to competition) to low threshold (physician clearance for return to play). Re-injury and contralateral injury rates are greater than the risk for primary ACL injury, which may be related to insufficient RTS guidelines based on time from surgery, which do not allow for proper healing or resolution of post-operative impairments and elimination of risk factors associated with both primary and secondary ACL injuries. Conclusions RTS rates to pre-injury level of activity after ACLR are poor and the risk for graft injury or contralateral injury requiring an additional surgery is substantial. Resolving impairments while eliminating movement patterns associated with

  5. THE ROLE AND IMPLEMENTATION OF ECCENTRIC TRAINING IN ATHLETIC REHABILITATION: TENDINOPATHY, HAMSTRING STRAINS, AND ACL RECONSTRUCTION

    PubMed Central

    Reiman, Michael

    2011-01-01

    The benefits and proposed physiological mechanisms of eccentric exercise have previously been elucidated and eccentric exercise has been used for well over seventy years. Traditionally, eccentric exercise has been used as a regular component of strength training. However, in recent years, eccentric exercise has been used in rehabilitation to manage a host of conditions. Of note, there is evidence in the literature supporting eccentric exercise for the rehabilitation of tendinopathies, muscle strains, and in anterior cruciate ligament (ACL) rehabilitation. The purpose of this Clinical Commentary is to discuss the physiologic mechanism of eccentric exercise as well as to review the literature regarding the utilization of eccentric training during rehabilitation. A secondary purpose of this commentary is to provide the reader with a framework for the implementation of eccentric training during rehabilitation of tendinopathies, muscle strains, and after ACL reconstruction. PMID:21655455

  6. Neuromuscular adaptations and correlates of knee functionality following ACL reconstruction.

    PubMed

    Bryant, Adam L; Kelly, Jason; Hohmann, Erik

    2008-01-01

    The objective of this research was to examine the dynamic restraint mechanism by establishing the neuromuscular characteristics of lower extremity muscles in anterior cruciate ligament reconstruction (ACLR) subjects. This study also investigated neuromuscular variables that relate to post-ACLR functional outcome. Thirteen patients having undergone ACLR using the bone patella tendon bone graft at least 6 months prior participated in this study. Knee functionality (0- to 100-point scale) was rated using the Cincinnati Knee Rating System. The median frequency of the electromyographic (EMG) recordings from the vastus medialis (VM) and vastus lateralis (VL) muscles together with the isokinetic quadriceps torque generated in 10 degrees intervals between 80 degrees and 10 degrees knee flexion was determined for the noninvolved and involved limbs. Lower limb musculotendinous stiffness was also assessed for the noninvolved and involved limbs. Limb symmetry indexes were calculated for each of the physiological measures. Compared to the noninvolved limb, the median frequency of the EMG from the involved limb VM and VL muscles was significantly lower as was the quadriceps torque generated at the seven knee flexion intervals. In contrast, musculotendinous stiffness was significantly higher in the involved lower limb compared to the noninvolved limb. Significant, moderate correlations were identified between knee functionality and symmetry indexes for all variables except for the isokinetic quadriceps torque produced between 80 degrees -70 degrees and 20 degrees -10 degrees knee flexion. More functional ACLR subjects demonstrated enhanced motor unit recruitment reflective of less quadriceps muscle fiber atrophy together with increased quadriceps strength and musculotendinous stiffness of the lower limb musculature.

  7. Effects of ACL reconstruction surgery on muscle activity of the lower limb during a jump-cut maneuver in males and females.

    PubMed

    Coats-Thomas, Margaret S; Miranda, Daniel L; Badger, Gary J; Fleming, Braden C

    2013-12-01

    We compared muscle activity of the quadriceps, hamstring, and gastrocnemius muscles when ACL-intact (ACL(INT)) and ACL-reconstructed (ACL(REC)) male and female subjects performed a jump-cut task. Surface electromyography sensors were used to evaluate time to peak muscle activity and muscle activity ratios. Rectus femoris (RF) and vastus medialis (VM) peak timing was 71 and 78 ms earlier in ACL(INT) than in ACL(REC) subjects, respectively. Biceps femoris (BF) peak timing was 90 ms earlier in ACL(INT) than in ACL(REC) subjects and 75 ms earlier in females than in males. Medial gastrocnemius (MG) muscle peak timing was 77 ms earlier in ACL(INT) than in ACL(REC) subjects. Lateral gastrocnemius (LG) and MG muscle peak times were 106 ms and 87 ms earlier in females than in males, respectively. The RF, VM, BF, and MG peaked later in ACL(REC) than in ACL(INT) subjects. There was evidence suggesting that the loading phase quadriceps:hamstring (quad:ham) muscle activity ratio was greater in ACL(REC) than in ACL(INT) subjects. Finally, the injury risk phase quad:ham muscle activity ratio was 4.8 times greater in females than in males. In conclusion, differences exist in muscle activity related to ACL status and sex that could potentially help explain graft failure risk and the sex bias.

  8. Effect of Calcium Phosphate–Hybridized Tendon Graft in Anatomic Single-Bundle ACL Reconstruction in Goats

    PubMed Central

    Mutsuzaki, Hirotaka; Fujie, Hiromichi; Nakajima, Hiromi; Fukagawa, Makoto; Nomura, Shunsuke; Sakane, Masataka

    2016-01-01

    Background: We previously developed a novel technique using an alternate soaking process that improves tendon-bone healing by hybridizing the tendon graft with calcium phosphate (CaP). However, the effects of the CaP-hybridized tendon graft on anatomic single-bundle anterior cruciate ligament (ACL) reconstruction remain unclear. Purpose: To determine the effects of CaP-hybridized tendon grafts compared with untreated tendon grafts 6 months after anatomic single-bundle ACL reconstruction using a goat model. Study Design: Controlled laboratory study. Methods: Animals were divided into a CaP group (n = 5 goats) and a control group (n = 5 goats), and we analyzed (1) knee kinematics and in situ forces under applied anterior tibial loads of 50 N and internal tibial torque of 2.0 N·m in the grafts at full extension and at 60° and 90° of knee flexion, (2) the mean percentage of bone tunnel enlargement using computed tomography (CT), and (3) the histology of the tendon-bone interface. Results: The in situ forces under applied anterior tibial loads of 50 N at 60° and 90° of knee flexion in the CaP group were greater than those in the control group (P < .05). The red safranin-O–stained area, indicating glycosaminoglycans in the cartilage layers at the joint aperture sites of the anterior femoral and posterior tibial bone tunnel, was greater in the CaP group than that in the control group (P < .05). The lengths of the nonbonding gap area between the anterior femoral and posterior tibial bone tunnels in the control group were greater than those in the CaP group (P < .05). No significant difference could be detected in the mean percentage of bone tunnel enlargement between the 2 groups. Conclusion: The CaP-hybridized tendon graft enhanced tendon-bone healing at the joint aperture site in both anterior femoral and posterior tibial tunnels 6 months after anatomic single-bundle ACL reconstruction in goats. The in situ forces under applied anterior tibial loads at greater

  9. Effect of Calcium Phosphate–Hybridized Tendon Graft in Anatomic Single-Bundle ACL Reconstruction in Goats

    PubMed Central

    Mutsuzaki, Hirotaka; Fujie, Hiromichi; Nakajima, Hiromi; Fukagawa, Makoto; Nomura, Shunsuke; Sakane, Masataka

    2016-01-01

    Background: We previously developed a novel technique using an alternate soaking process that improves tendon-bone healing by hybridizing the tendon graft with calcium phosphate (CaP). However, the effects of the CaP-hybridized tendon graft on anatomic single-bundle anterior cruciate ligament (ACL) reconstruction remain unclear. Purpose: To determine the effects of CaP-hybridized tendon grafts compared with untreated tendon grafts 6 months after anatomic single-bundle ACL reconstruction using a goat model. Study Design: Controlled laboratory study. Methods: Animals were divided into a CaP group (n = 5 goats) and a control group (n = 5 goats), and we analyzed (1) knee kinematics and in situ forces under applied anterior tibial loads of 50 N and internal tibial torque of 2.0 N·m in the grafts at full extension and at 60° and 90° of knee flexion, (2) the mean percentage of bone tunnel enlargement using computed tomography (CT), and (3) the histology of the tendon-bone interface. Results: The in situ forces under applied anterior tibial loads of 50 N at 60° and 90° of knee flexion in the CaP group were greater than those in the control group (P < .05). The red safranin-O–stained area, indicating glycosaminoglycans in the cartilage layers at the joint aperture sites of the anterior femoral and posterior tibial bone tunnel, was greater in the CaP group than that in the control group (P < .05). The lengths of the nonbonding gap area between the anterior femoral and posterior tibial bone tunnels in the control group were greater than those in the CaP group (P < .05). No significant difference could be detected in the mean percentage of bone tunnel enlargement between the 2 groups. Conclusion: The CaP-hybridized tendon graft enhanced tendon-bone healing at the joint aperture site in both anterior femoral and posterior tibial tunnels 6 months after anatomic single-bundle ACL reconstruction in goats. The in situ forces under applied anterior tibial loads at greater

  10. A tale of 10 European centres – 2010 APOSSM travelling fellowship review in ACL surgery

    PubMed Central

    2012-01-01

    The purpose of ESSKA- APOSSM Travelling fellowship is to better understand the epidemiology, management and surgical techniques for sports across continents. There has been a progressive evolution in ACL reconstruction and there is variation in technique in ACL reconstruction amongst the most experienced surgeons in different continents. During this one month fellowship, we saw various ACL reconstruction techniques using different graft sources, with a variety of graft fixation methods, with the common aim of recreating an anatomical ACL reconstruction. PMID:22839644

  11. KNEE KINEMATICS FOLLOWING ACL RECONSTRUCTION IN FEMALES; THE EFFECT OF VISION ON PERFORMANCE DURING A CUTTING TASK

    PubMed Central

    Di Fabio, Richard P.

    2011-01-01

    Purpose/Background: Specific movement patterns have been identified as influential in ACL injury; however several key kinematic variables that might be predictive of future performance have not been fully investigated. The purpose of this research was to: 1) determine if subjects with ACL reconstruction display different displacement, velocity, and time to peak ground reaction force (GRF) during cutting activities than healthy subjects, 2) observe if subjects with visual disruption display differences in these variables, and 3) determine if visual disruption alters these variables in subjects with ACL reconstruction relative to healthy subjects. Methods: Seventeen healthy female subjects and 17 female subjects with unilateral ACL reconstruction (ACLR) performed 40 trials of a cutting movement during which knee position was measured via a 3D electromagnetic system. Visual conditions were randomized to disrupt vision for 1 second as the subject began the cutting movement, or allow full vision for movement duration. Independent variables were lead/push off leg (ACLR limb or healthy non-dominant limb) and vision (disrupted or full). 2-way ANOVAs were utilized to determine differences between knee kinematics using dependent variables of displacement (m), absolute velocity (m/sec), and time to reach peak GRF (% of cut). Results: Knee displacement was significantly less for ACLR (.76±.11; .75±.16) than non-dominant (.85±.08; .87±.12). Knee velocity was significantly slower for ACLR (.81±.14; .84±.16) than non-dominant (.92±.11; .97±.14). A significant interaction was noted for displacement and average velocity (p<.05). Time to reach peak GRF was significantly longer for ACLR (79.41±2.28) than non-dominant (76.65±4.41). Conclusions: Subjects with ACLR displayed less knee displacement, slower velocity, and an increased time to reach peak GRF relative to healthy subjects' non-dominant knee. Visual disruption appeared to have some effect on movement, as noted by

  12. Gait analysis in patients undergoing ACL reconstruction according to Kenneth Jones' technique.

    PubMed

    Bacchini, Massimo; Cademartiri, Carola; Soncini, Giovanni

    2009-08-01

    The anterior cruciate ligament is essential for knee stability, and its injury, both acute and in the case of chronic knee instability, promotes meniscal degenerative alterations, as well as the onset and progression of gonarthrosis. In this retrospective study, young adults engaged in nonprofessional sportive activities undergoing ACL reconstruction by the Kenneth-Jones technique were assessed clinically and with gait analysis, to detect any deficits persisting even after rehabilitation at a follow- up of approximately 6 months. Eight patients who had undergone elective ligament reconstruction by Kenneth-Jones were assessed between the 5th and 7th month postsurgery with clinical-anamnestic investigation, including the Hughston Clinic subjective knee questionnaire and by gait analysis with the EL.I.Te. system. Gait analysis showed a reduction of ACL protection mechanisms during initial stance; furthermore, the operated limb globally exhibited greater difficulty in muscle recruitment. Residual deficits in muscle recruitment, exposing the reconstructed ligament to possible injuries, persist after a rehabilitation program and after resuming ofpre-surgery activities, thus adjustment of the rehabilitative program on the basis of these findings is recommended.

  13. ACL reconstruction

    MedlinePlus

    Anterior cruciate ligament repair ... Micheo W, Amy E, Sepuleveda F. Anterior cruciate ligament tear. In: Frontera, WR, Silver JK, Rizzo TD, eds. Essentials of Physical Medicine and Rehabilitation . 3rd ed. Philadelphia, PA: Elsevier Saunders; 2015: ...

  14. Combination of Eccentric Exercise and Neuromuscular Electrical Stimulation to Improve Quadriceps Function Post-ACL Reconstruction

    PubMed Central

    Lepley, Lindsey K.; Wojtys, Edward M.; Palmieri-Smith, Riann M.

    2014-01-01

    Background Neuromuscular electrical stimulation (NMES) has been shown to reduce quadriceps activation failure (QAF), and eccentric exercise has been shown lessen muscle atrophy post-ACL reconstruction. Given that these are two critical components of quadriceps strength, intervention combining these therapies may be effective at reinstituting quadriceps function post-anterior cruciate ligament (ACL) reconstruction. Objectives To evaluate the effectiveness of a combined NMES and eccentric exercise intervention to improve the recovery of quadriceps activation and strength post-reconstruction. Design Parallel longitudinal design. Setting Laboratory. Participants Thirty-six individuals post-injury were placed into four treatment groups (N&E, NMES and eccentrics; E-only, eccentrics only; N-only, NMES-only; STND, standard of care) and ten healthy controls participated. Intervention N&E and N-only received the NMES protocol 2x per week for the first six weeks post-reconstruction. N&E and E-only received the eccentric exercise protocol 2x per week beginning six weeks post-reconstruction. Main outcome measure Quadriceps activation was assessed via the superimposed burst technique and quantified via the central activation ratio. Quadriceps strength was assessed via maximal voluntary isomeric contractions (Nm/kg). Data was gathered on three occasions: pre-operative, 12-weeks-post-surgery and at return-to-play. Results No differences in pre-operative measures existed (P>0.05). E-only recovered quadriceps activation better than N-only or STND (P<0.05). N&E and E-only recovered strength better than N-only or the STND (P<0.05) and had strength values that were similar to healthy individuals at return-to-play (P>0.05). Conclusion Eccentric exercise was capable of restoring levels of quadriceps activation and strength that were similar to those of healthy adults and better than NMES alone. PMID:25819154

  15. Persons with reconstructed ACL exhibit altered knee mechanics during high-speed maneuvers.

    PubMed

    Lee, S-P; Chow, J W; Tillman, M D

    2014-06-01

    Anterior cruciate ligament (ACL) injury is a sports trauma that causes long-term disability. The function of the knee during dynamic activities can be severely limited even after successful surgical reconstruction. This study examined the effects of approach velocity during side-step cutting on knee joint mechanics in persons with reconstructed ACL (ACLR). 22 participants (11 with unilateral ACLR, 11 matched-controls) participated. Knee joint mechanics were tested in 3 approach conditions: counter-movement, one-step, and running. Dependent variables, including peak knee flexion, extension, valgus, varus, internal rotation, external rotation angles and corresponding peak joint moments, were assessed during the stance phase of cutting. Two 2×3 ("group" by "approach condition") mixed MANOVA tests were used to examine the effects of ACLR and approach velocity on knee mechanics. ACLR participants exhibited higher knee internal rotator moment (0.22 vs. 0.13 Nm/kg, p=0.003). Inter-group comparisons revealed that the ACLR participants exhibited significantly higher abductor and internal rotator moments only in the running condition (1.86 vs. 1.16 Nm/kg, p=0.018; 0.28 vs. 0.17 Nm/kg, p=0.010, respectively). Our findings suggested that patients with ACLR may be at increased risk of re-injury when participating in high-demand physical activities. Task demand should be considered when prescribing progressive therapeutic interventions to ACLR patients.

  16. Validation of GAITRite and PROMIS as High-Throughput Physical Function Outcome Measures Following ACL Reconstruction

    PubMed Central

    Papuga, M. Owen; Beck, Christopher A.; Kates, Stephen L.; Schwarz, Edward M.; Maloney, Michael D.

    2014-01-01

    New healthcare demands for quality measures of elective procedures, such as anterior cruciate ligament (ACL) reconstructive surgery, warrant the establishment of high through-put outcomes for high volume clinics. To this end we evaluated the PROMIS and GAITRite as physical function outcome measures to quantify early healing and post-operative complications in 106 patients at pre-op and 3, 10, 20 and 52 weeks post-ACL reconstruction with bone-tendon-bone autograft, and compared the results to the current IKDC validated outcome measure. The results showed that both PROMIS and GAITRite were significantly quicker to administer versus IKDC (p < 0.0001). Additional advantages were that PROMIS and GAITRite detected a significant decrease in physical function at 3 weeks post-op, and a significant improvement at 10 weeks post-op, versus pre-op (p<0.001), which were not detected with IKDC. GAITRite was limited by a low ceiling that could not detect improvement of physical function beyond 20 weeks, while both PROMIS and IKDC detected significant improvement out to 52 weeks postop (p<0.001). Linear regressions demonstrated a significant relationship between IKDC and PROMIS, with a combined correlation value of 0.8954 (p<.001) for all time points. Finally, ROC curve analysis demonstrated that PROMIS is a diagnostic test for poor outcomes. PMID:24532421

  17. Panoramic Measurement and Analysis of Strain Distribution in the Human ACL Using a Photoelastic Coating Method

    NASA Astrophysics Data System (ADS)

    Hirokawa, Shunji; Yamamoto, Kouji; Kawada, Takashi

    Large and highly variable deformations of the ACL cannot be adequately quantified by one-dimensional and/or localized measurements. Since the complex anatomy of the ACL makes uniform loading of all fiber bundles almost impossible, strains on specific portions being tested are considerably altered during knee movement. To observe the ACL's entire surface, we propose a photoelastic coating method. A simulator jig was used to allow a natural motion of the knee whose medial and lateral femoral bone parts were removed in order to expose the ACL for observation. The simulator jig with the knee was mounted on a universal stand which allows tilt and swivel rotations, so that the exposed ACL might be viewed from any direction. Measurements were performed on the strain distributions over the ACL at various knee angles. The panoramic images of the photoelastic fringe patterns yielded significant results. Special attention was paid for insight into the relation between strain distribution and the directions of fiber run.

  18. Return to sport after ACL reconstruction: how, when and why? A narrative review of current evidence.

    PubMed

    Zaffagnini, Stefano; Grassi, Alberto; Serra, Margherita; Marcacci, Maurilio

    2015-01-01

    Allowing a patient to return to sport and unrestricted physical activity after ACL injury and reconstruction is one of the most challenging and difficult decisions an orthopaedic surgeon has to make. Indeed, many factors have to be taken into account before it can be considered safe for a patients to load a reconstructed knee. The current literature contains plenty of studies aimed at evaluating return to sport, and the factors that may affect or predict this outcome, e.g. intrinsic factors like genetics, biology, type of lesion, anatomical features, motivation and psychology, and extrinsic factors such as graft type, surgical technique, rehabilitation protocols, and biological support. It is possible that awareness of these issues could help the clinician to optimise outcomes, and possibly avoid failures too, although as yet no universal criteria for resuming sport have been produced. PMID:26151036

  19. Return to sport after ACL reconstruction: how, when and why? A narrative review of current evidence

    PubMed Central

    ZAFFAGNINI, STEFANO; GRASSI, ALBERTO; SERRA, MARGHERITA; MARCACCI, MAURILIO

    2015-01-01

    Allowing a patient to return to sport and unrestricted physical activity after ACL injury and reconstruction is one of the most challenging and difficult decisions an orthopaedic surgeon has to make. Indeed, many factors have to be taken into account before it can be considered safe for a patients to load a reconstructed knee. The current literature contains plenty of studies aimed at evaluating return to sport, and the factors that may affect or predict this outcome, e.g. intrinsic factors like genetics, biology, type of lesion, anatomical features, motivation and psychology, and extrinsic factors such as graft type, surgical technique, rehabilitation protocols, and biological support. It is possible that awareness of these issues could help the clinician to optimise outcomes, and possibly avoid failures too, although as yet no universal criteria for resuming sport have been produced. PMID:26151036

  20. ACL reconstructed patients with a BPTB graft present an impaired vastus lateralis neuromuscular response during high intensity running.

    PubMed

    Patras, Kostas; Ziogas, Giorgos; Ristanis, Stavros; Tsepis, Elias; Stergiou, Nicholas; Georgoulis, Anastasios D

    2010-11-01

    The purpose of the present study was to investigate whether the electromyographic response of the vastus lateralis (VL) muscle in the anterior cruciate ligament (ACL) reconstructed leg is similar to that of the intact contralateral leg and healthy controls, during moderate and high intensity running. Fourteen bone-patellar tendon-bone (BPTB) ACL reconstructed amateur soccer players and fourteen healthy control amateur soccer players volunteered to participate in the study. Electromyographic (EMG) traces from the vastus lateralis (VL) muscle were collected bilaterally, as athletes ran on a treadmill for 10 min on separate occasions, at moderate and high intensity. The dependent variable examined was the EMG amplitude during stance. During the moderate intensity running, EMG amplitude of the VL did not increase with time for any of the tested legs. During the high intensity running, the EMG amplitude of the VL increased significantly with time for the intact (F=6.747, p=0.001) and the control leg (F=4.258, p=0.008), but remained unchanged for the ACL reconstructed leg. During moderate intensity running, there was no difference in the neuromuscular response of the VL in the reconstructed leg compared to the intact and control leg. High intensity running resulted in an impaired neuromuscular response of the VL in the reconstructed leg compared to the intact and control leg. It seems that potential impairments of the neuromuscular response after ACL reconstruction should be tested under high rather than moderate intensity efforts.

  1. COMPARATIVE STUDY OF ACL RECONSTRUCTION WITH ANATOMICAL POSITIONING OF THE TUNNELS USING THE PATELLAR TENDON VERSUS HAMSTRING TENDON

    PubMed Central

    de Pádua, Vitor Barion Castro; Maldonado, Hilário; Vilela, Júlio César Rodrigues; Provenza, Alexandre Ribeira; Monteiro, Cleverson; de Oliveira Neto, Heleno Cavalcante

    2015-01-01

    Objective: To compare ACL reconstruction with anatomical positioning of the tunnels using the hamstring or patellar tendons. Methods: We prospectively evaluated 52 patients who underwent ACL reconstruction using the Chambat's technique, with anatomical positioning of the tunnels drilled outside in. They were divided into group A, with 27 patients, using the patellar tendon as a graft, and group B, with 25 patients, using the hamstring. Results: In group A 26 patients were very satisfied or satisfied and 1 unhappy, in group B. 25 patients were very satisfied or satisfied with the procedure (p = 0.990). According to the Lysholm scale, group A had a mean score of 96.11 and group B, 95.32 (p=0.594). In relation to preoperative IKDC, 100% of the patients in group A and 92% of those in group B were IKDC C or D (p = 0.221); in the assessment with a minimum of two-year follow-up, 96% of group A and 92% of group B were IKDC A or B (p = 0.256). The Lachman test, pivot shift, return to sports activities, and the comparative difference in anterior translation (RolimeterTM) also showed no statistically significant difference. In group A, 5 patients (18.5%) were unable to kneel on a hard surface, whereas no patient in group B had this complaint. Conclusion: The anterior cruciate ligament reconstruction presents similar results using the hamstring or patellar tendon with anatomical positioning of the tunnels. Drilling the femoral tunnel outside in is a reproducible and accurate option in the correct placement the femoral tunnel. PMID:27027082

  2. Quadriceps Strength Asymmetry Following ACL Reconstruction Alters Knee Joint Biomechanics and Functional Performance at Time of Return to Activity

    PubMed Central

    Palmieri-Smith, RM; Lepley, LK

    2016-01-01

    Background Quadriceps strength deficits are observed clinically following anterior cruciate injury and reconstruction and are often not overcome despite rehabilitation. Given that quadriceps strength may be important for achieving symmetrical joint biomechanics and promoting long-term joint health, determining the magnitude of strength deficits that lead to altered mechanics is critical. Purpose To determine if the magnitude of quadriceps strength asymmetry alters knee and hip biomechanical symmetry, as well as functional performance and self-reported function. Study Design Cross-Sectional study. Methods Seventy-three patients were tested at the time they were cleared for return to activity following ACL reconstruction. Quadriceps strength and activation, scores on the International Knee Documentation Committee form, the hop for distance test, and sagittal plane lower extremity biomechanics were recorded while patients completed a single-legged hop. Results Patients with high and moderate quadriceps strength symmetry had larger central activation ratios as well as greater limb symmetry indices on the hop for distance compared to patients with low quadriceps strength symmetry (P<0.05). Similarly, knee flexion angle and external moment symmetry was higher in the patients with high and moderate quadriceps symmetry compared to those with low symmetry (P<0.05). Quadriceps strength was found to be associated with sagittal plane knee angle and moment symmetry (P<0.05). Conclusion Patients with low quadriceps strength displayed greater movement asymmetries at the knee in the sagittal plane. Quadriceps strength was related to movement asymmetries and functional performance. Rehabilitation following ACL reconstruction needs to focus on maximizing quadriceps strength, which likely will lead to more symmetrical knee biomechanics. PMID:25883169

  3. In vivo bone tunnel remodeling in symptomatic patients after ACL reconstruction: a retrospective comparison of articular and extra-articular fixation

    PubMed Central

    Mathis, Dominic T.; Rasch, Helmut; Hirschmann, Michael T.

    2015-01-01

    Summary Background there is only a paucity of studies dealing with bone remodeling within the tunnels after anterior cruciate ligament (ACL) reconstruction. The objective of this study was to evaluate the influence of tendon graft type and surgical fixation technique on bone tunnel remodeling in patients with symptomatic knees after ACL reconstruction. Methods in a retrospective study 99mTc-HDP bone tracer uptake (BTU) in SPECT/CT of 57 knees with symptoms of pain and/or instability after ACL reconstruction was investigated. All 57 knees were subdivided according their anatomy (femur and tibia), fixation (articular versus extra-articular fixation) and graft types into eight groups: femoral-articular versus extra-articular fixation using bone-patellar tendon-bone (BPTB) and hamstring autografts; tibial-articular versus extra-articular fixation using patellar tendon and hamstring autografts; BTU grading for each area of the localisation scheme were recorded. Tunnel diameter and length was measured in the CT scans. Results BTU was higher for the articular fixation in the femur and for the extra-articular fixation in the tibial tunnel. Patellar tendon graft fixation showed a significantly higher BTU in the superior-lateral and posterior-central area of the tibia, meaning the areas of the tibial tunnel near the entrance into the joint. Tunnel enlargement correlated significantly with increased BTU (p<0.05). Conclusion assessment of in vivo bone tunnel remodelling in symptomatic patients after ACL reconstruction revealed different patterns of BTU with regards to graft and fixation method. PMID:26958543

  4. Is there significant variation in the material properties of four different allografts implanted for ACL reconstruction.

    PubMed

    Penn, David; Willet, Thomas L; Glazebrook, Mark; Snow, Martyn; Stanish, William D

    2009-03-01

    The aims of our study were to: (1) determine if there are differences in the material properties of tendon obtained from implanted tibialis anterior, achilles, bone-patella- bone and tibialis posterior allografts; (2) determine the variability in material properties between the implanted specimens. A total of 60 specimens were collected from fresh frozen allografts implanted at ACL reconstruction. Specimens collected included 15 tibialis anterior, 15 tibialis posterior, 15 achilles and 15 bone-patella-bone tendons. Each specimen was mounted in a custom made cryogrip. The mounted specimens were loaded onto a MTS Testline servo-hydraulic testing machine in a uni-axial tensile test configuration. Specimens were subjected to a strain rate of 5% per second until the ultimate tensile stress (UTS), failure strain and high strain modulus was calculated for each specimen after being normalized for specimen dimensions. Individual material properties were tested using one way analysis of variance (ANOVA) and post hoc Tukey's B test with a P value of <0.05 considered significant. Homogeneity of variance was assessed using the Levene's test. As a result, no significant difference was found between all four grafts with regards to UTS, failure strain or high strain linear modulus. The UTS was plotted against the modulus demonstrating a linear relationship which is typical of soft tissues. Significant variability in the results were observed. In conclusion, there was no significant statistical difference between the material properties of the four tendon allografts tested. But significant variability in results was observed within groups and between groups, which may provide one explanation for the range of results in allograft ACL reconstruction reported in the literature.

  5. Predictive mathematical modeling of knee static laxity after ACL reconstruction: in vivo analysis.

    PubMed

    Signorelli, C; Bonanzinga, T; Grassi, A; Lopomo, N; Zaffagnini, S; Marcacci, M

    2016-11-01

    Previous studies did not take into consideration such large variety of surgery variables which describe the performed anterior cruciate ligament (ACL) reconstruction and the interaction among them in the definition of postoperative outcome. Seventeen patients who underwent navigated Single Bundle plus Lateral Plasty ACL reconstruction were enrolled in the study. Static laxity was evaluated as the value of anterior/posterior displacement at 30° and at 90° of flexion, internal/external rotation at 30° and 90° of knee flexion, varus/valgus test at 0° and 30° of flexion. The evaluated surgical variables were analyzed through a multivariate analysis defining the following models: AP30estimate, AP90estimate, IE30estimate, IE90estimate, VV0estimate, VV30estimate. Surgical variables has been defined as the angles between the tibial tunnel and the three planes, the lengths of the tunnel and the relationship between native footprints and tunnels. An analogous characterization was performed for the femoral side. Performance and significance of the defined models have been quantified by the correlation ratio (η(2)) and the corresponding p-value (*p < 0.050). The analyzed models resulted to be statistically significant (p < 0.05) for prediction of postoperative static laxity values. The only exception was the AP90estimate model. The η(2) ranged from 0.568 (IE90estimate) to 0.995 (IE30estimate). The orientation of the tibial tunnel resulted to be the most important surgical variable for the performed laxity estimation. Mathematical models for postoperative knee laxity is a useful tool to evaluate the effects of different surgical variables on the postoperative outcome.

  6. Is there significant variation in the material properties of four different allografts implanted for ACL reconstruction.

    PubMed

    Penn, David; Willet, Thomas L; Glazebrook, Mark; Snow, Martyn; Stanish, William D

    2009-03-01

    The aims of our study were to: (1) determine if there are differences in the material properties of tendon obtained from implanted tibialis anterior, achilles, bone-patella- bone and tibialis posterior allografts; (2) determine the variability in material properties between the implanted specimens. A total of 60 specimens were collected from fresh frozen allografts implanted at ACL reconstruction. Specimens collected included 15 tibialis anterior, 15 tibialis posterior, 15 achilles and 15 bone-patella-bone tendons. Each specimen was mounted in a custom made cryogrip. The mounted specimens were loaded onto a MTS Testline servo-hydraulic testing machine in a uni-axial tensile test configuration. Specimens were subjected to a strain rate of 5% per second until the ultimate tensile stress (UTS), failure strain and high strain modulus was calculated for each specimen after being normalized for specimen dimensions. Individual material properties were tested using one way analysis of variance (ANOVA) and post hoc Tukey's B test with a P value of <0.05 considered significant. Homogeneity of variance was assessed using the Levene's test. As a result, no significant difference was found between all four grafts with regards to UTS, failure strain or high strain linear modulus. The UTS was plotted against the modulus demonstrating a linear relationship which is typical of soft tissues. Significant variability in the results were observed. In conclusion, there was no significant statistical difference between the material properties of the four tendon allografts tested. But significant variability in results was observed within groups and between groups, which may provide one explanation for the range of results in allograft ACL reconstruction reported in the literature. PMID:19039574

  7. Predictive mathematical modeling of knee static laxity after ACL reconstruction: in vivo analysis.

    PubMed

    Signorelli, C; Bonanzinga, T; Grassi, A; Lopomo, N; Zaffagnini, S; Marcacci, M

    2016-11-01

    Previous studies did not take into consideration such large variety of surgery variables which describe the performed anterior cruciate ligament (ACL) reconstruction and the interaction among them in the definition of postoperative outcome. Seventeen patients who underwent navigated Single Bundle plus Lateral Plasty ACL reconstruction were enrolled in the study. Static laxity was evaluated as the value of anterior/posterior displacement at 30° and at 90° of flexion, internal/external rotation at 30° and 90° of knee flexion, varus/valgus test at 0° and 30° of flexion. The evaluated surgical variables were analyzed through a multivariate analysis defining the following models: AP30estimate, AP90estimate, IE30estimate, IE90estimate, VV0estimate, VV30estimate. Surgical variables has been defined as the angles between the tibial tunnel and the three planes, the lengths of the tunnel and the relationship between native footprints and tunnels. An analogous characterization was performed for the femoral side. Performance and significance of the defined models have been quantified by the correlation ratio (η(2)) and the corresponding p-value (*p < 0.050). The analyzed models resulted to be statistically significant (p < 0.05) for prediction of postoperative static laxity values. The only exception was the AP90estimate model. The η(2) ranged from 0.568 (IE90estimate) to 0.995 (IE30estimate). The orientation of the tibial tunnel resulted to be the most important surgical variable for the performed laxity estimation. Mathematical models for postoperative knee laxity is a useful tool to evaluate the effects of different surgical variables on the postoperative outcome. PMID:27123692

  8. Knee stability, athletic performance and sport-specific tasks in non-professional soccer players after ACL reconstruction: comparing trans-tibial and antero-medial portal techniques

    PubMed Central

    Tudisco, Cosimo; Bisicchia, Salvatore; Cosentino, Andrea; Chiozzi, Federica; Piva, Massimo

    2015-01-01

    Summary Background a wrong position of bone tunnels, in particular on the femur, is one of the most frequent causes of a failed anterior cruciate ligament (ACL) reconstruction. Several studies demonstrated that drilling the femoral tunnel through the antero-medial portal (AMP) allows a more anatomical placement on the lateral femoral condyle and higher knee stability, compared to trans-tibial (TT) technique. The aim of this study was to retrospectively evaluate two groups of soccer players operated on for ACL reconstruction according to either one of these two techniques. Methods two groups of non-professional soccer players operated on for a single bundle ACL reconstruction with hamstrings autograft using either a TT (20 patients) or an AMP (23 patients) technique were retrospectively evaluated with KT-1000 arthrometer, manual pivot shift test, isokinetic test, the incremental treadmill-running test, athletic and sport specific tasks, and knee scores (IKDC, Lysholm and KOOS). Results the AMP group showed better results at pivot shift test and KOOS, but lower flexion angles at single leg squat test. There were no differences in all the other considered outcomes. Conclusions the better rotational stability of the knee achieved in AMP group did not lead to significantly better clinical and functional results in our patients. Level of evidence III. Treatment study Case-control study. PMID:26605191

  9. Calcium phosphate-hybridized tendon graft to enhance tendon-bone healing two years after ACL reconstruction in goats

    PubMed Central

    2011-01-01

    Background We developed a novel technique to improve tendon-bone attachment by hybridizing calcium phosphate (CaP) with a tendon graft using an alternate soaking process. However, the long-term result with regard to the interface between the tendon graft and the bone is unclear. Methods We analyzed bone tunnel enlargement by computed tomography and histological observation of the interface and the tendon graft with and without the CaP hybridization 2 years after anterior cruciate ligament (ACL) reconstruction in goats using EndoButton and the postscrew technique (CaP, n = 4; control, n = 4). Results The tibial bone tunnel enlargement rates in the CaP group were lower than those in the control group (p < 0.05). In the CaP group, in the femoral and tibial bone tunnels at the anterior and posterior of the joint aperture site, direct insertion-like formation that contained a cartilage layer without tidemarks was more observed at the tendon-bone interface than in the control group (p < 0.05). Moreover, the gap area between the tendon graft and the bone was more observed at the femoral bone tunnel of the joint aperture site in the control group than in the CaP group (p < 0.05). The maturation of the tendon grafts determined using the ligament tissue maturation index was similar in both groups. Conclusions The CaP-hybridized tendon graft enhanced the tendon-bone healing 2 years after ACL reconstruction in goats. The use of CaP-hybridized tendon grafts can reduce the bone tunnel enlargement and gap area associated with the direct insertion-like formation in the interface near the joint. PMID:22166674

  10. Treatment of Type 3 Arthrofibrosis Following Arthroscopic Reconstruction of ACL and Posterolateral Corner Injury with Tibia Plateau Fracture in a Professional Dancer

    PubMed Central

    Aksu, Neslihan; Abay, Burak; Soydan, Ramazan; Atansay, Vefa

    2014-01-01

    Objectives: Arthrofibrosis is a serious complication following the reconstruction of anterior cruciate ligament (ACL) and posterolateral corner (PLC) injury. Loss of motion caused by arthrofibrosis can be disabling in young and active patients. We report the clinical results of the treatment of arthrofibrosis following arthroscopic reconstruction of ACL with ipsilateral hamstring tendon graft and surgically repairing PLC with 2 suture anchors in a 30 year-old professional dancer, treated with surgical lysis and manipulation under general anesthesia followed by aggressive physical therapy. Methods: A 30 year-old male professional dancer presented with pain, effusion and severe instability in his left knee after falling in a dance event. The pain was evaluated on Visual analog scale (VAS) as 6 to 8. At the physical examination, anterior drawer test was evaluated as grade 3, pivot shift test, varus test, dial test and posterolateral drawer test were found positive. The Tegner Lysholm score was evaluated as 22 (poor). Under general anesthesia, left knee had tendency to external rotation and recurvatum when leg was suspended by toes. A magnetic resonance image (MRI) revealed the presence of a total ACL rupture, PLC injury and a fracture of lateral tibia plateau. The patient was treated with arthroscopic reconstruction of ACL with ipsilateral hamstring tendon graft fixed with endobutton through femoral tunnel and bio interference screw through tibial tunnel and PLC injury was treated with 2 suture anchors. Postoperatively first day, quadriceps musculature and active and passive ROM exercises was trained. During postoperatively third week, the patient was allowed to mobilize nonweight bearing with the use of two crutches without functional knee brace. At the sixth week, arthroscopic lysis was performed due to type 3 arthrofibrosis. At the tenth week, manipulation was performed to the left knee under general anesthesia. Results: At the 3 month- follow-up, the patient

  11. Anatomic ACL reconstruction: rectangular tunnel/bone-patellar tendon-bone or triple-bundle/semitendinosus tendon grafting.

    PubMed

    Shino, Konsei; Mae, Tatsuo; Tachibana, Yuta

    2015-05-01

    Anatomic ACL reconstruction is the reasonable approach to restore stability without loss of motion after ACL tear. To mimic the normal ACL like a ribbon, our preferred procedures is the anatomic rectangular tunnel (ART) technique with a bone-patellar tendon-bone (BTB) graft or the anatomic triple bundle (ATB) procedure with a hamstring (HS) tendon graft. It is important to create tunnel apertures inside the attachment areas to lessen the tunnel widening. To identify the crescent-shaped ACL femoral attachment area, the upper cartilage margin, the posterior cartilage margin and the resident's ridge are used as landmarks. To delineate the C-shaped tibial insertion, medial intercondylar ridge, Parson's knob and anterior horn of the lateral meniscus are helpful. In ART-BTB procedure which is suitable for male patients engaged in contact sports, the parallelepiped tunnels with rectangular apertures are made within the femoral and tibial attachment areas. In ATB-HS technique which is mainly applied to female athletes engaged in non-contact sports including skiing or basketball, 2 femoral and 3 tibial round tunnels are created inside the attachment areas. These techniques make it possible for the grafts to run as the native ACL without impingement to the notch or PCL. After femoral fixation with an interference screw or cortical fixation devices including Endobutton, the graft is pretensioned in situ by repetitive manual pulls at 15-20° of flexion, monitoring the graft tension with tensioners on a tensioning boot installed on the calf. Tibial fixation with pullout sutures is achieved using Double Spike Plate and a screw at the pre-determined amount of tension of 10-20N. While better outcomes with less failure rate are being obtained compared to those in the past, higher graft tear rate remains a problem. Improved preventive training may be required to avoid secondary ACL injuries.

  12. Anatomic ACL reconstruction: rectangular tunnel/bone-patellar tendon-bone or triple-bundle/semitendinosus tendon grafting.

    PubMed

    Shino, Konsei; Mae, Tatsuo; Tachibana, Yuta

    2015-05-01

    Anatomic ACL reconstruction is the reasonable approach to restore stability without loss of motion after ACL tear. To mimic the normal ACL like a ribbon, our preferred procedures is the anatomic rectangular tunnel (ART) technique with a bone-patellar tendon-bone (BTB) graft or the anatomic triple bundle (ATB) procedure with a hamstring (HS) tendon graft. It is important to create tunnel apertures inside the attachment areas to lessen the tunnel widening. To identify the crescent-shaped ACL femoral attachment area, the upper cartilage margin, the posterior cartilage margin and the resident's ridge are used as landmarks. To delineate the C-shaped tibial insertion, medial intercondylar ridge, Parson's knob and anterior horn of the lateral meniscus are helpful. In ART-BTB procedure which is suitable for male patients engaged in contact sports, the parallelepiped tunnels with rectangular apertures are made within the femoral and tibial attachment areas. In ATB-HS technique which is mainly applied to female athletes engaged in non-contact sports including skiing or basketball, 2 femoral and 3 tibial round tunnels are created inside the attachment areas. These techniques make it possible for the grafts to run as the native ACL without impingement to the notch or PCL. After femoral fixation with an interference screw or cortical fixation devices including Endobutton, the graft is pretensioned in situ by repetitive manual pulls at 15-20° of flexion, monitoring the graft tension with tensioners on a tensioning boot installed on the calf. Tibial fixation with pullout sutures is achieved using Double Spike Plate and a screw at the pre-determined amount of tension of 10-20N. While better outcomes with less failure rate are being obtained compared to those in the past, higher graft tear rate remains a problem. Improved preventive training may be required to avoid secondary ACL injuries. PMID:25753837

  13. Nonoperative management of a partial patellar tendon rupture after bone-patellar tendon-bone graft harvest for ACL reconstruction.

    PubMed

    Benner, Rodney W; Shelbourne, K Donald; Freeman, Heather

    2013-12-01

    This is a case report of a young athlete who sustained a partial tear of the patellar tendon after anterior cruciate ligament (ACL) reconstruction with a bone-patellar tendon-bone (BPTB) autograft. The injury, diagnostic workup, and decision-making process that lead to the choice of nonsurgical treatment are described. Furthermore, the rehabilitation process is described in detail. The patient returned to his previous level of sports activity and had a good clinical outcome as measured by range of motion, isokinetic quadriceps muscle strength testing, single leg hop testing, and the modified Noyes survey. In the absence of extensor mechanism incompetence or radiographic evidence of significant patella alta, partial ruptures of the patella tendon after ACL reconstruction using a BPTB autograft may be treated nonoperatively.

  14. The location-specific healing response of damaged articular cartilage after ACL reconstruction: short-term follow-up.

    PubMed

    Nakamura, Norimasa; Horibe, Shuji; Toritsuka, Yukiyoshi; Mitsuoka, Tomoki; Natsu-ume, Takashi; Yoneda, Kenji; Hamada, Masayuki; Tanaka, Yoshinari; Boorman, Richard S; Yoshikawa, Hideki; Shino, Konsei

    2008-09-01

    Although many different interventions have been proposed for treating cartilage lesions at the time of ACL reconstruction, the normal healing response of these injuries has not been well documented. To address this point, we compared the arthroscopic status of chondral lesions at the time of ACL reconstruction with that obtained at second-look arthroscopy. We hypothesized that there might be a location-specific difference in the healing response of damaged articular cartilage. Between September 1998 and March 2000, 383 patients underwent arthroscopically-assisted hamstring ACL reconstruction without any intervention to the articular cartilage. Among these patients, 84 patients underwent second-look arthroscopy (ranging from 6 to 52 months following initial surgery) and make up the population of the present study. Chondral injuries, left untreated at ACL reconstruction, were arthroscopically evaluated using the Outerbridge classification, and were again evaluated at second-look arthroscopy. At second-look arthroscopy, there was significant recovery of chondral lesions by Outerbridge grading on both the medial and lateral femoral condyles. Among the recovered chondral lesions, 69% of cases of the medial femoral condyle, 88% of cases of the lateral femoral condyle were partial thickness injuries (grade I and II). Conversely, there was no significant recovery of chondral lesions observed at the patello-femoral joint or tibial plateaus. Our study revealed that there was a location-specific difference in the natural healing response of chondral injury. Untreated cartilage lesions on the femoral condlyes had a superior healing response compared to those on the tibial plateaus, and in the patello-femoral joint.

  15. BIOMECHANICAL STUDY OF TRANSCORTICAL OR TRANSTRABECULAR BONE FIXATION OF PATELLAR TENDON GRAFT WITH BIOABSORBABLE PINS IN ACL RECONSTRUCTION IN SHEEP

    PubMed Central

    Albano, Mauro Batista; Borges, Paulo César; Namba, Mario Massatomo; da Silva, João Luiz Vieira; de Assis Pereira Filho, Francisco; Filho, Edmar Stieven; Matias, Jorge Eduardo Fouto

    2015-01-01

    Objective: To determine the initial resistance of fixation using the Rigid Fix® system, and compare it with traditional fixation methods using metal interference screws; and to evaluate the resistance of the fixation with the rigid fix system when the rotational position of the bone block is altered in the interior of the femoral tunnel. Methods: forty ovine knee specimens (stifle joints) were submitted to anterior cruciate ligament reconstruction (ACL) using a bone-tendon-bone graft. In twenty specimens, the Rigid Fix method was used; this group was subdivided into two groups: ten knees the pins transfixed only the spongious area of the bone block, and ten for fixation passing through the layer of cortical bone. In the twenty remaining specimens, the graft was fixed with 9mm metal interference screws. Results: comparison of the RIGIDFIX® method with the metal interference screw fixation method did not show any statistically significant differences in terms of maximum load and rigidity; also, there were no statistically significant differences when the rotational position of the bone block was altered inside the femoral tunnel. For these evaluations, a level of significance of p < 0.017 was considered. Conclusion: fixation of the bone-tendon-bone graft with 2 bioabsorbable pines, regardless of the rotational position inside the femoral tunnel, gave a comparable fixation in terms of initial resistance to the metal interference screw, in this experimental model. PMID:27027081

  16. An intelligent recovery progress evaluation system for ACL reconstructed subjects using integrated 3-D kinematics and EMG features.

    PubMed

    Malik, Owais A; Senanayake, S M N Arosha; Zaheer, Dansih

    2015-03-01

    An intelligent recovery evaluation system is presented for objective assessment and performance monitoring of anterior cruciate ligament reconstructed (ACL-R) subjects. The system acquires 3-D kinematics of tibiofemoral joint and electromyography (EMG) data from surrounding muscles during various ambulatory and balance testing activities through wireless body-mounted inertial and EMG sensors, respectively. An integrated feature set is generated based on different features extracted from data collected for each activity. The fuzzy clustering and adaptive neuro-fuzzy inference techniques are applied to these integrated feature sets in order to provide different recovery progress assessment indicators (e.g., current stage of recovery, percentage of recovery progress as compared to healthy group, etc.) for ACL-R subjects. The system was trained and tested on data collected from a group of healthy and ACL-R subjects. For recovery stage identification, the average testing accuracy of the system was found above 95% (95-99%) for ambulatory activities and above 80% (80-84%) for balance testing activities. The overall recovery evaluation performed by the proposed system was found consistent with the assessment made by the physiotherapists using standard subjective/objective scores. The validated system can potentially be used as a decision supporting tool by physiatrists, physiotherapists, and clinicians for quantitative rehabilitation analysis of ACL-R subjects in conjunction with the existing recovery monitoring systems.

  17. Validation of a novel method for quantifying and comparing regional ACL elongations during uniaxial tensile loading.

    PubMed

    Beaulieu, Mélanie L; Haladik, Jeffrey A; Bey, Michael J; McLean, Scott G

    2012-10-11

    Given the complex three-dimensional (3D) knee joint loading associated with anterior cruciate ligament (ACL) injuries, accurate site- and bundle-specific strain measurements are critical. The purpose of this study was to quantify tensile load-induced migrations of radio-opaque markers injected directly into the ACL, as a first step in validating a roentgen stereophotogrammetric analysis-based method for measuring ligament strain. Small markers were inserted into the femur and tibia, as well as injected into the antero-medial bundle of the ACL of eight (42-56 yrs) femur-ACL-tibia complexes (FATCs). The FATCs were then loaded under tension along the ligament's longitudinal axis by a material testing machine from 10 N to 50 N, 100 N, 125 N, and 150 N, each over 10 load-unload cycles. Complexes were imaged before the loading protocol, between each loading sequence, and after the protocol via biplane radiography. Marker migrations within the ACL tissue were quantified as the difference in their 3D positions between the pre- and each post-loading condition. Negligible migration was evident, with the lowest average root mean square values observed along the longitudinal axis of the ACL, ranging from 0.128 to 0.219 mm. Further, neither marker location nor load magnitude significantly affected migration values. This innovative method, therefore, presents as a plausible means to measure global and regional ACL strains, as small as 0.75% strain. In particular, it may provide important new insights in ACL strain behaviors during complex 3D knee load states associated with ligament injury. PMID:22939290

  18. Selective anteromedial bundle reconstruction in partial ACL tears: a series of 36 patients with mean 24 months follow-up.

    PubMed

    Sonnery-Cottet, Bertrand; Lavoie, F; Ogassawara, R; Scussiato, R G; Kidder, J F; Chambat, P

    2010-01-01

    The purpose of this study was to describe an original technique of reconstruction of the anteromedial bundle preserving the posterolateral bundle and to report the results of a consecutive 36 patients series with mean 24 months follow-up. Our hypothesis is that this selective reconstruction of ACL partial tears could restore knee stability and function. In a consecutive series of 256, ACL reconstructions, 36 patients in which intact ACL fibers remained in the location corresponding to the posterolateral bundle were perioperatively diagnosed. These patients (21 women and 15 men) underwent isolated reconstruction of the anteromedial bundle while keeping the remaining fibers intact. AM bundle reconstructions were performed by the same surgeon using an outside-in technique. A quadrupled hamstring graft was used in 20 patients and a doubled semitendinosus graft in 16 patients. The mean age of the patients at the time of surgery was 32 years (min 15, max 53). The delay between injury and surgery was 6.6 months (min 2, max 35). Patients were assessed with the IKDC ligament evaluation form. Instrumented knee testing was performed with the Rolimeter arthrometer. Statistical analysis was performed to compare the preoperative and postoperative objective evaluation. Eleven concomitant meniscal lesions at the time of reconstruction were found. One patient who underwent a traumatic graft rupture at 4 months post surgery and two patients with previous contralateral ACL reconstruction were excluded, leaving 33 patients for final evaluation. Three reoperations were performed, including two arthrolysis for cyclops syndrome and one revision for a traumatic graft rupture. At last follow-up, 24 (73%) patients were graded A, 8 (24%) graded B and 1 C (3%) at IKDC objective evaluation. Mean side to side instrumented laxity was 4.8 mm (min 3, max 6) preoperatively and 0.8 mm (min 0, max 2) postoperatively. AM bundle reconstruction with an outside-in technique remains simple and

  19. Lower limb asymmetry in mechanical muscle function: A comparison between ski racers with and without ACL reconstruction.

    PubMed

    Jordan, M J; Aagaard, P; Herzog, W

    2015-06-01

    Due to a high incidence of anterior cruciate ligament (ACL) re-injury in alpine ski racers, this study aims to assess functional asymmetry in the countermovement jump (CMJ), squat jump (SJ), and leg muscle mass in elite ski racers with and without anterior cruciate ligament reconstruction (ACL-R). Elite alpine skiers with ACL-R (n = 9; 26.2 ± 11.8 months post-op) and uninjured skiers (n = 9) participated in neuromuscular screening. Vertical ground reaction force during the CMJ and SJ was assessed using dual force plate methodology to obtain phase-specific bilateral asymmetry indices (AIs) for kinetic impulse (CMJ and SJ phase-specific kinetic impulse AI). Dual x-ray absorptiometry scanning was used to assess asymmetry in lower body muscle mass. Compared with controls, ACL-R skiers had increased AI in muscle mass (P < 0.001), kinetic impulse AI in the CMJ concentric phase (P < 0.05), and the final phase of the SJ (P < 0.05). Positive associations were observed between muscle mass and AI in the CMJ concentric phase (r = 0.57, P < 0.01) as well as in the late SJ phase (r = 0.66, P < 0.01). Future research is required to assess the role of the CMJ and SJ phase-specific kinetic impulse AI as a part of a multifaceted approach for improving outcome following ACL-R in elite ski racers.

  20. A medium to long-term follow-up of ACL reconstruction using double gracilis and semitendinosus grafts.

    PubMed

    Ferretti, Andrea; Monaco, Edoardo; Giannetti, Silvio; Caperna, Ludovico; Luzon, David; Conteduca, Fabio

    2011-03-01

    This paper reports the results of our approach to ACL tears and knee laxity, based on 30 years of experience in ACL reconstruction with hamstrings and founded on the following cornerstones: the use of doubled semitendinosus and gracilis as a free graft; the use of an out-in technique for femoral drilling and of very strong and stiff fixation devices; the careful examination and repair or reconstruction of the lateral compartment in selected patients; and the use of unaggressive rehabilitation. We prospectively evaluated a series of 100 consecutive patients who underwent ACL reconstruction between 2001 and 2002. A clinical and radiological follow-up was performed at a minimum of 6 years. After 6 years, the International Knee Documentation Committee score demonstrated good-to-excellent results (A and B) in 98% of patients. However, arthrometric results using the KT-1000 demonstrated that 6/80 patients (7.5%) had >5 mm manual maximum side-to-side difference. The median Tegner activity score was 5 (range 1-9); the median Lysholm score was 96 (range 81-100); and the median subjective IKDC score was 94 (range 66-100). We reported 6/80 failures as revealed by a 2+ or 3+ pivot-shift test result and/or KT-1000 side-to-side difference of more than 5 mm. The IKDC score revealed excellent results in all women who underwent extra-articular tenodesis. Radiographic evaluation demonstrated early signs of osteoarthritis in 9% of patients.

  1. The Potentially Positive Role of PRPs in Preventing Femoral Tunnel Widening in ACL Reconstruction Surgery Using Hamstrings: A Clinical Study in 51 Patients

    PubMed Central

    Starantzis, Konstantinos A.; Mastrokalos, Dimitrios; Koulalis, Dimitrios; Papakonstantinou, Olympia; Soucacos, Panayiotis N.; Papagelopoulos, Panayiotis J.

    2014-01-01

    Purpose. In this study, the early and midterm clinical and radiological results of the anterior cruciate ligament (ACL) reconstruction surgery with or without the use of platelet rich plasma (PRP) focusing on the tunnel-widening phenomenon are evaluated. Methods. This is a double blind, prospective randomized study. 51 patients have completed the assigned protocol. Recruited individuals were divided into two groups: a group with and a group without the use of PRPs. Patients were assessed on the basis of MRI scans, which were performed early postoperatively and repeated at least one-year postoperatively. The diameter was measured at the entrance, at the bottom, and at the mid distance of the femoral tunnel. Results. Our study confirmed the existence of tunnel widening as a phenomenon. The morphology of the dilated tunnels was conical in both groups. There was a statistical significant difference in the mid distance of the tunnels between the two groups. This finding may support the role of a biologic response secondary to mechanical triggers. Conclusions. The use of RPRs in ACL reconstruction surgery remains a safe option that could potentially eliminate the biologic triggers of tunnel enlargement. The role of mechanical factors, however, remains important. PMID:26464895

  2. Functional Outcome Following Arthroscopic ACL Reconstruction with Rigid Fix: A Retrospective Observational Study

    PubMed Central

    Shervegar, Satish; Nagaraj, Prashanth; Grover, Amit; DJ, Niranthara Ganesh; Ravoof, Abdul

    2015-01-01

    Background: No uniform consensus exists to decide type of fixation for arthroscopic anterior cruciate ligament reconstruction. Hypothsis: There is similar functional outcome after rigid fix compared to other methods of fixation which has been published. Study design: Retrospective observational study. Methods: A total of 50 patients underwent arthroscopic anterior cruciate ligament reconstruction with hamstring tendons using femoral Rigid fix cross-pin and interference screw tibial fixation. The evaluation methods were clinical examination, IKDC scores, Lysholm and pre injury and post reconstruction Tegner score. Patients were followed up from minimum of 6 months to 4 year seven months. Results: C In our study of sample size 50 we found that mean age of patients was 30.8 Years with male preponderance. Mean post operative IKDC and Lysholm score has been 75.6 and 84.4 respectively. Mean Tegner pre-injury score and post reconstruction score has been 5.4 and 4.26. Box plot comparison of pre injury and post operativeTegner score reveals a statistically significant difference with respect to paired t test P<0.001. Conclusions: Arthroscopic anterior cruciate ligament reconstruction with femoral rigid fix cross pins and tibial interference screws results in comparable short term to midterm functional results compared to other types of fixation PMID:26550591

  3. Assessing the progress of rehabilitation in patients with ACL reconstruction using the International Knee Documentation Committee Subjective Knee Form

    NASA Astrophysics Data System (ADS)

    Leguizamon, J. H.; Braidot, A.; Catalfamo Formento, P.

    2011-12-01

    There are numerous assessment tools designed to provide information on the results of reconstructive surgery of anterior cruciate ligament (ACL). They are also used for monitoring progress and facilitating clinical decision-making during the rehabilitation process. A brief summary of some existing tools specifically designed to evaluate knee ligament injuries is presented in this article. Then, one of those outcome measures, the International Knee Documentation Committee Subjective Knee Form (IKDC) was applied to a group of patients (N = 10) who had undergone surgery for ACL reconstruction. The patients attended the same physiotherapy service and followed a unified rehabilitation protocol. The assessment was performed twice: four and six months after surgery. The results showed an improvement in the rehabilitation of most patients tested (verified by a difference equal to or greater than 9 points on the IKDC outcome between measurements 1 and 2). The IKDC probed to be an instrument of quick and easy application. It provided quantitative data about the progress of rehabilitation and could be applied in everyday clinical physiotherapy practice. However, the results suggested considering the IKDC as one component of an evaluation kit to make decisions regarding the progress of the rehabilitation treatment.

  4. Risk Factors at Time of Primary ACL Reconstruction that Contribute to Significant Chondral Surface Change at Time of Revision ACL Reconstruction

    PubMed Central

    Kaeding, Christopher C.; Group, Mars

    2016-01-01

    Objectives: Articular cartilage health is an important issue following primary anterior cruciate ligament reconstruction (ACLR). It is not clear what risk factors at the time of primary reconstruction affect future articular cartilage health. The purpose of this study was to examine risk factors affecting chondral surface change in a cohort from the time of primary ACLR to revision ACLR. Methods: Subjects who had both primary and revision data contained in the MOON and MARS registries were included. Data included chondral surface status (grade and size) at time of primary and revision, meniscal status (no treatment/repair, ≤33% excision, >33% excision) at time of primary, time from primary to revision ACLR, and age, sex, BMI, Marx, KOOS, and IKDC at time of revision. Significant chondral surface change was defined as >25% deterioration between time of primary and revision in the femoral condyle, tibial plateau, patella, or trochlea. Logistic regression was used to test each variable’s contribution to significant chondral surface change in the medial compartment, lateral compartment, and patellofemoral compartment. Results: 134 subjects met our inclusion criteria. 34/134 (25.4%) had significant lateral compartment chondral surface change, 32/134 (23.9%) had significant medial compartment chondral surface change, and 31/134 (23.1%) had significant patellofemoral chondral surface change. Median age at time of revision was 19.5 years [IQ range 17-25] and median time from primary to revision was 462.5 days [IQ range 292-1049]. KOOS and IKDC at revision were not associated with significant chondral surface change in any compartment. Patients with >33% of their lateral meniscus excised had 13.5 times the odds of having significant lateral compartment surface change compared to subjects who either did not have lateral meniscal damage, had it repaired, or had an excision of ≤33% controlling for age (p<0.001). Patients with ≤33% excision of their medial meniscus had

  5. The Influence of Task Complexity on Knee Joint Kinetics Following ACL Reconstruction

    PubMed Central

    Schroeder, Megan J.; Krishnan, Chandramouli; Dhaher, Yasin Y.

    2015-01-01

    Background Previous research indicates that subjects with anterior cruciate ligament reconstruction exhibit abnormal knee joint movement patterns during functional activities like walking. While the sagittal plane mechanics have been studied extensively, less is known about the secondary planes, specifically with regard to more demanding tasks. This study explored the influence of task complexity on functional joint mechanics in the context of graft-specific surgeries. Methods In 25 participants (10 hamstring tendon graft, 6 patellar tendon graft, 9 matched controls), three-dimensional joint torques were calculated using a standard inverse dynamics approach during level walking and stair descent. The stair descent task was separated into two functionally different sub-tasks—step-to-floor and step-to-step. The differences in external knee moment profiles were compared between groups; paired differences between the reconstructed and non-reconstructed knees were also assessed. Findings The reconstructed knees, irrespective of graft type, typically exhibited significantly lower peak knee flexion moments compared to control knees during stair descent, with the differences more pronounced in the step-to-step task. Frontal plane adduction torque deficits were graft-specific and limited to the hamstring tendon knees during the step-to-step task. Internal rotation torque deficits were also primarily limited to the hamstring tendon graft group during stair descent. Collectively, these results suggest that task complexity was a primary driver of differences in joint mechanics between anterior cruciate ligament reconstructed individuals and controls, and such differences were more pronounced in individuals with hamstring tendon grafts. Interpretation The mechanical environment experienced in the cartilage during repetitive, cyclical tasks such as walking and other activities of daily living has been argued to contribute to the development of degenerative changes to the joint

  6. Effect of graft choice on the outcome of revision anterior cruciate ligament reconstruction in the Multicenter ACL Revision Study (MARS) Cohort

    PubMed Central

    Wright, Rick W.; Huston, Laura J.; Haas, Amanda K.; Spindler, Kurt P.; Nwosu, Sam K.; Allen, Christina R.; Anderson, Allen F.; Cooper, Daniel E.; DeBerardino, Thomas M.; Dunn, Warren R.; Lantz, Brett (Brick) A.; Stuart, Michael J.; Garofoli, Elizabeth A.; Albright, John P.; Amendola, Annunziato (Ned); Andrish, Jack T.; Annunziata, Christopher C.; Arciero, Robert A.; Bach, Bernard R.; Baker, Champ L.; Bartolozzi, Arthur R.; Baumgarten, Keith M.; Bechler, Jeffery R.; Berg, Jeffrey H.; Bernas, Geoffrey A.; Brockmeier, Stephen F.; Brophy, Robert H.; Bush-Joseph, Charles A.; Butler, J. Brad; Campbell, John D.; Carey, James L.; Carpenter, James E.; Cole, Brian J.; Cooper, Jonathan M.; Cox, Charles L.; Creighton, R. Alexander; Dahm, Diane L.; David, Tal S.; Flanigan, David C.; Frederick, Robert W.; Ganley, Theodore J.; Gatt, Charles J.; Gecha, Steven R.; Giffin, James Robert; Hame, Sharon L.; Hannafin, Jo A.; Harner, Christopher D.; Harris, Norman Lindsay; Hechtman, Keith S.; Hershman, Elliott B.; Hoellrich, Rudolf G.; Hosea, Timothy M.; Johnson, David C.; Johnson, Timothy S.; Jones, Morgan H.; Kaeding, Christopher C.; Kamath, Ganesh V.; Klootwyk, Thomas E.; Levy, Bruce A.; Ma, C. Benjamin; Maiers, G. Peter; Marx, Robert G.; Matava, Matthew J.; Mathien, Gregory M.; McAllister, David R.; McCarty, Eric C.; McCormack, Robert G.; Miller, Bruce S.; Nissen, Carl W.; O'Neill, Daniel F.; Owens, Brett D.; Parker, Richard D.; Purnell, Mark L.; Ramappa, Arun J.; Rauh, Michael A.; Rettig, Arthur C.; Sekiya, Jon K.; Shea, Kevin G.; Sherman, Orrin H.; Slauterbeck, James R.; Smith, Matthew V.; Spang, Jeffrey T.; Svoboda, Steven J.; Taft, Timothy N.; Tenuta, Joachim J.; Tingstad, Edwin M.; Vidal, Armando F.; Viskontas, Darius G.; White, Richard A.; Williams, James S.; Wolcott, Michelle L.; Wolf, Brian R.; York, James J.

    2015-01-01

    Background Most surgeons believe that graft choice for ACL reconstruction is an important factor related to outcome. Although graft choice may be limited in the revision setting based on previously used grafts, it is still felt to be important. Hypothesis The purpose of this study was to determine if revision ACL graft choice predicts outcomes related to sports function, activity level, OA symptoms, graft re-rupture, and reoperation at two years following revision reconstruction. We hypothesized that autograft use would result in increased sports function, increased activity level, and decreased OA symptoms (as measured by validated patient reported outcome instruments). Additionally, we hypothesized that autograft use would result in decreased graft failure and reoperation rate 2 years following revision ACL reconstruction. Study Design Prospective cohort study; Level of evidence, 2. Methods Revision ACL reconstruction patients were identified and prospectively enrolled by 83 surgeons over 52 sites. Data collected included baseline demographics, surgical technique and pathology, and a series of validated patient reported outcome instruments (IKDC, KOOS, WOMAC, and Marx activity rating score). Patients were followed up at 2 years, and asked to complete the identical set of outcome instruments. Incidence of additional surgery and reoperation due to graft failure were also recorded. Multivariate regression models were used to determine the predictors (risk factors) of IKDC, KOOS, WOMAC, Marx scores, graft re-rupture, and reoperation rate at 2 years following revision surgery. Results 1205 patients were successfully enrolled with 697 (58%) males. Median age was 26. In 88% this was their first revision. 341 (28%) were undergoing revision by the surgeon that had performed the previous reconstruction. 583 (48%) underwent revision reconstruction utilizing an autograft, 590 (49%) allograft, and 32 (3%) both autograft and allograft. Median time since their last ACL

  7. Effect of Intraoperative Platelet-Rich-Plasma Treatment on Post Operative Donor Site Knee Pain in Patellar Tendon Autograft ACL Reconstruction

    PubMed Central

    Walters, Brian L.; Hobart, Sarah; Porter, David; Hogan, Daniel E.; McHugh, Malachy P.; Bedford, Benjamin B.; Nicholas, Stephen J.; Klein, Devon; Harousseau, Kendall

    2016-01-01

    Objectives: Donor site morbidity in the form of anterior knee pain is a frequent complication after bone-patellar tendon-bone (BPTB) autograft ACL reconstruction. The purpose of this Level I study was to examine the effect of the intraoperative administration of platelet-rich plasma on post operative knee pain and patellar defect healing. Methods: Fifty-nine patients (29±12 y/o) undergoing BPTB ACL reconstruction and eligible to enter the study, were randomized to the treatment (PRP; n=31) or non treatment (sham n=28) arms of the study just prior to surgery. In either case, 10 cc of venous blood was drawn prior to the induction of anesthesia and either discarded (sham) or processed (PRP) for preparation of a PRP gel to be later mixed with donor site bone chips and inserted into the patellar defect. At 12 weeks and 6 months after surgery, patients completed IKDC forms and VAS pain scores for ADLs and kneeling (0-10 scale). Healing indices at the donor site were assessed by MRI at 6 months and included the following measurements taken from axial sequences: AP tendon dimensions at the level of the superior tibial cortex, roof of the intercondylar notch and width at the largest patella graft deficit. Mixed model ANOVA was used to assess the effect of PRP on patient symptoms and MRI indices of donor site healing. The primary dependent variable was VAS kneeling pain. It was estimated that with 25 patients per group there would be 80% power to detect a 1.5-point difference in kneeling pain between treatments at P<0.05. A between group difference of 1.5-points in VAS for kneeling pain was deemed to represent a clinically relevant difference. Results: VAS Kneeling Pain at 12 weeks tended to be lower in the PRP versus placebo group (4.5±3.6 vs. 6.2±2.4, P=0.051) but no difference was apparent at 6 months (3.7±3.2 vs. 4.4±2.9, P=0.41). Kneeling pain decreased from 12 weeks to 6 months (P<0.001) with a trend for a greater decrease in the placebo group (Time by Treatment P

  8. What is the best candidate allograft for ACL reconstruction? An in vitro mechanical and histologic study in a canine model.

    PubMed

    Qu, Jin; Thoreson, Andrew R; An, Kai-Nan; Amadio, Peter C; Zhao, Chunfeng

    2015-07-16

    The knee joint is generally characterized by very low friction and high wear resistance. Several previous studies have compared ACL with the commonly used allografts from tensile properties perspective. No study has reported about the graft tendons from a frictional perspective, which is an important parameter for ACL functional performance. Twenty hind legs were used to harvest FDP tendon, ACL, ACH, and patellar tendon. Samples were evaluated with surface friction testing, indentation testing for tendon compressive moduli, lubricin immunohistochemistry, and histologic analysis. Frictional force of FDP tendon and ACL was significantly less than that of patellar tendon and ACH at first and fifth cycles. At the tenth cycle, the FDP tendon, ACL, and ACH showed significantly less frictional force than patellar tendon; after 100 cycles, the FDP tendon and ACL showed significantly less frictional force than patellar tendon. The compressive moduli of the FDP tendon, ACL, and ACH were significantly greater than that of patellar tendon. Histologic results showed that FDP tendon and ACL had a smooth surface with a thin layer of epitenon cells; patellar tendon and ACH had a rough surface and a layer of paratenon. Lubricin was found on the surface and extracellular matrix of FDP tendon and ACL. There was only limited lubricin expression on the surface and extracellular matrix of the ACH and patellar tendon. The FDP tendon has friction force and lubricin expression similar to those of native ACL. However, patellar tendon and ACH show higher friction force and less lubricin expression than ACL. PMID:25981102

  9. Histological Predictors of Maximum Failure Loads Differ Between the Healing ACL and ACL Grafts After 6 and 12 Months In Vivo

    PubMed Central

    Proffen, Benedikt L.; Fleming, Braden C.; Murray, Martha M.

    2013-01-01

    Background: Bioenhanced anterior cruciate ligament (ACL) repair, where the suture repair is supplemented with a biological scaffold, is a promising novel technique to stimulate healing after ACL rupture. However, the histological properties of a successfully healing ACL and how they relate to the mechanical properties have not been fully described. Purpose: To determine which histological features best correlate with the mechanical properties of the healing ACL repairs and ACL grafts in a porcine model at 6 and 12 months after injury. Study Design: Controlled laboratory study. Methods: A total of 48 Yucatan mini-pigs underwent ACL transection followed by: (1) conventional ACL reconstruction with bone–patellar tendon–bone (BPTB) allograft, (2) bioenhanced ACL reconstruction with BPTB allograft using a bioactive scaffold, or (3) bioenhanced ACL repair using the same bioactive scaffold. After 6 and 12 months of healing, structural properties of the ACL or graft (yield and failure load, linear stiffness) were measured. Following mechanical testing, ACL specimens were histologically analyzed for cell and vascular density and qualitatively assessed using the advanced Ligament Maturity Index. Results: After 6 months of healing, the cellular organization subscore was most predictive of yield load (r 2 = 0.98), maximum load (r 2 = 0.89), and linear stiffness (r 2 = 0.95) of the healing ACL, while at 12 months, the collagen subscore (r 2 = 0.68) became the best predictor of maximum load. For ACL grafts, the reverse was true, with the collagen subscore predictive of yield and maximum loads at 6 months (r 2 = 0.55) and graft cellularity predictive of maximum load of the graft at 12 months (r 2 = 0.50). Conclusion: These findings suggest there may be key biological differences in development and maintenance of ACL tissue after repair or reconstruction, with early ligament function dependent on cellular population of the repair but early graft function dependent on the

  10. Analytical Chemistry Laboratory (ACL) procedure compendium. Volume 4, Organic methods

    SciTech Connect

    Not Available

    1993-08-01

    This interim notice covers the following: extractable organic halides in solids, total organic halides, analysis by gas chromatography/Fourier transform-infrared spectroscopy, hexadecane extracts for volatile organic compounds, GC/MS analysis of VOCs, GC/MS analysis of methanol extracts of cryogenic vapor samples, screening of semivolatile organic extracts, GPC cleanup for semivolatiles, sample preparation for GC/MS for semi-VOCs, analysis for pesticides/PCBs by GC with electron capture detection, sample preparation for pesticides/PCBs in water and soil sediment, report preparation, Florisil column cleanup for pesticide/PCBs, silica gel and acid-base partition cleanup of samples for semi-VOCs, concentrate acid wash cleanup, carbon determination in solids using Coulometrics` CO{sub 2} coulometer, determination of total carbon/total organic carbon/total inorganic carbon in radioactive liquids/soils/sludges by hot persulfate method, analysis of solids for carbonates using Coulometrics` Model 5011 coulometer, and soxhlet extraction.

  11. Increased Risk of Revision after ACL Reconstruction with Soft Tissue Allograft Compared to Autograft

    PubMed Central

    Maletis, Gregory; Chen, Jason; Inacio, Maria Carolina Secorun; Love, Rebecca; Funahashi, Tadashi Ted

    2016-01-01

    Objectives: The use of allograft tissue for anterior cruciate ligament reconstruction (ACLR) remains controversial. Numerous meta-analysis and systematic reviews of small clinical studies have not found differences between autograft and allograft outcomes but large registry studies have shown an increased risk of revision with allografts. The purpose of this study was to compare the risk of aseptic revision between bone-patellar tendon-bone (BPTB) autografts, hamstring tendon autografts and soft tissue allografts. Methods: A retrospective cohort study of prospectively collected data was conducted using an US ACLR Registry. A cohort of primary unilateral ACLR cases reconstructed with BPTB autografts, hamstring autografts and soft tissue allografts (from any site) was identified. Aseptic revision was the end point of the study. Type of graft and allograft processing methods (non-processed, <1.8Mrads with and without chemical processing (Allowash or AlloTrue methods), >1.8 Mrads irradiation with and without chemical processing, and chemical processing alone (BioCleanse)) were the exposures of interest evaluated. Time from surgery was evaluated as an effect modifier. All analyses were adjusted for age, gender, and race. Kaplan-Meier curves and Cox proportional hazard models were employed. Hazard ratios (HR), 95% confidence intervals (CI) are provided. Results: The cohort had 14015 cases, 8924 (63.7%) were male, 6397 (45.6%) were White, 4557 (32.5%) cases used BPTB autograft, 3751 (26.8%) cases used soft tissue allograft and 5707 (40.7%) cases used hamstring autograft. The median age was 34.6 years-old (IQR 24.1-43.2) for allograft cases and 24.3 years-old (IQR 17.7-33.8) for hamstring autograft cases, and 22.0 years-old (IQR 17.6-30.0) for BPTB autograft cases. Compared to hamstring tendon autografts, an increased risk of revision was found in allografts processed with >1.8Mrads without chemical processing after 2.5 years (HR: 3.88 95%CI 1.48-10.12), and >1.8Mrads with

  12. Biomechanical Deficiencies in Women with Semitendinosus-Gracilis ACL Reconstruction During Drop Jumps

    PubMed Central

    Ortiz, Alexis; Capo-Lugo, Carmen E.; Venegas-Rios, Heidi L.

    2014-01-01

    Objective To compare landing mechanics and neuromuscular recruitment strategies between women with semitendinosus-gracilis anterior cruciate ligament reconstruction (SG-ACLr) and non-injured women during double and single-legged drop jumps. Design Cross-sectional biomechanical study Setting Single university-based biomechanics laboratory Participants Fourteen women 1–5 years post SG-ACLr and 16 non-injured women participated in this study. Methods After anthropometric measurements, warm-up, and familiarization procedures, participants performed five trials of a double and single-legged drop jumps. Main Outcome Measurements Dynamic knee valgus was measured as the distance between knee joints during the landing phase of the double-leg drop jumps. Medial knee displacement was the outcome considered during the landing phase of the single-leg drop jumps. For both drop jumps tasks neuromuscular recruitment was evaluated through rectified normalized electromyography (EMG) activity of the quadriceps and hamstrings (amplitude and latency), and quadriceps/hamstrings EMG co-contraction ratio. Results Although the SG- ACLr group demonstrated a tendency towards a greater dynamic knee valgus during both drop jumps, these differences did not reach statistical significance. EMG data revealed different neuromuscular strategies for each group depending on the specific jump. Conclusions These findings suggest that women with SG-ACLr have a tendency towards greater dynamic knee valgus which could predispose to additional knee injuries. Rehabilitation specialists need to be aware of existing kinematic and neuromuscular deficiencies years after SG-ACLr. Taking this into consideration will aid in prescribing appropriate interventions designed to prevent re-injury. PMID:25043260

  13. Functional tests should be accentuated more in the decision for ACL reconstruction.

    PubMed

    Eitzen, Ingrid; Moksnes, Håvard; Snyder-Mackler, Lynn; Engebretsen, Lars; Risberg, May Arna

    2010-11-01

    A high pre-injury activity level, the desire of the patient to continue pivoting sports and fear of future give-way episodes are considered the most significant factors affecting the decision to perform anterior cruciate ligament reconstruction. However, since the functional status of the knee at the time of surgery affects the final outcome, assessments of knee function should be considered in the decision making for surgery. Individuals with anterior cruciate ligament injury can be classified as potential copers or non-copers from an existing screening examination. The purpose of this study was to investigate whether the functional tests incorporated in the original screening examination could contribute to explain those who later go through anterior cruciate ligament reconstruction and to examine whether changes to the content or the time of conducting the screening examination (before or after ten sessions of exercise therapy) could improve its explanatory value. One-hundred and forty-five individuals were included and prospectively followed for 15 months, after where 51% had gone through anterior cruciate ligament reconstruction and 49% were managed non-operatively. The only significant baseline differences between those who later went through anterior cruciate ligament reconstruction and those who were non-operatively treated were that those who had surgery were younger and had a higher activity level (P < 0.05). Regression analyses revealed that the explanatory value for those who later went through anterior cruciate ligament reconstruction significantly improved when the original screening examination was considered compared to only age, activity level and give-way episodes. Changes to the content further improved the explanatory value, with quadriceps muscle strength as the single variable with the highest impact. Finally, conducting the screening examination after ten sessions of progressive exercise therapy gave the overall highest explanatory values

  14. Electromechanical delay of the knee extensor muscles is not altered after harvesting the patellar tendon as a graft for ACL reconstruction: implications for sports performance.

    PubMed

    Georgoulis, A D; Ristanis, S; Papadonikolakis, A; Tsepis, E; Moebius, U; Moraiti, C; Stergiou, N

    2005-09-01

    Although the scar tissue, which heals the donor site defect, has different elasticity from the neighbouring patellar tissue, it remains unclear if this scar tissue can lead to the changes of the electromechanical delay (EMD) of the knee extensor muscles. If such changes do exist, they can possibly affect both the utilization of the stored energy in the series elastic component, as well as the optimal performance of the knee joint movement. The purpose of this study was to investigate the influence of harvesting the patellar tendon during anterior cruciate ligament (ACL) reconstruction and the associated patellar tendon scar tissue development on the EMD of the rectus femoris (RF) and vastus medialis (VM) muscles. Seventeen patients who underwent an ACL reconstruction using the medial third of the patellar tendon were divided in two groups based upon their post-operative time interval. Maximal voluntary contraction from the knee extensors, surface EMG activity, and ultrasonographic measurements of the patellar tendon cross-section area were obtained from both knees. Our results revealed that no significant changes for the maximal voluntary contraction of the knee extensors and for the EMD of the RF and the VM muscles due to patellar scar tissue development after harvesting the tendon for ACL reconstruction. The EMD, as a component of the stretch reflex, is important for the utilization of the stored energy in the series elastic component and thus, optimal sports performance. However, from our results, it can be implied that the ACL reconstruction using a patellar tendon graft would not impair sports performance as far as EMD is concerned.

  15. The immunosuppressive effect of Siglecs on tendon-bone healing after ACL reconstruction.

    PubMed

    Hu, Jiang; Yao, Bin; Yang, Xiao; Ma, Fang

    2015-01-01

    The quality of the bone-tendon healing is very important to the surgery outcome after anterior cruciate ligament reconstruction. The necrosis of autograft and local new blood vessels occur after the surgery. The fibroblasts and mesenchymal cells presenting in the tendon-bone interface as well as the infiltrated of neutrophils and macrophages improve the biomechanical properties of the healing. We hypothesize that immunosuppressive effect of Siglecs which present on the surface of neutrophils and macrophages play the important roles to regulate acute local inflammatory reaction, maintain the physiological environment and induce the differentiation of the pluripotent cells to form the accepted histologic structure healing of the tendon-bone interface. It might be helpful to understand the mechanism of tendon-bone healing.

  16. Effects of Single-Bundle and Double-Bundle ACL Reconstruction on Tibiofemoral Compressive Stresses and Joint Kinematics During Simulated Squatting

    PubMed Central

    Mulcahey, Mary K.; Monchik, Keith O.; Yongpravat, Charlie; Badger, Gary J.; Fadale, Paul D.; Hulstyn, Michael J.; Fleming, Braden C.

    2011-01-01

    The purpose of this study was to compare tibiofemoral (TF) kinematics and TF compressive stresses between single bundle- (SB-) and double bundle-ACL reconstruction (DB-ACLR) during simulated squatting. Twelve matched pairs of fresh frozen cadaver knees were utilized. A simulated squat through 100° of knee flexion was performed in the ACL-intact joint. The ACL was transected and SB- and DB-ACLR procedures were performed in one knee of each pair. The squat was repeated. Knee kinematics were measured using a motion tracking system and the TF compressive forces were measured using thin film pressure sensors. The posterior shifts of the tibia for SB- and DB-ACLR knees were significantly greater than the ACL-intact condition for knee flexion angles 0° to 40° (p<.05). However, there was no difference between the SB- and DB-ACLR knees at any flexion angle (0° to 100°; p=.37). SB- and DB-ACLR knees had greater IE rotation than intact knees from 90° through 50° of flexion (p<.05), but not between 40° and full extension. There was no difference between SB- and DB-ACLR knees (p=.68). The TF compressive stresses of the DB-ACLR were significantly lower than intact for all angles except 10° (p=.06), whereas SB-ACLR knees did not differ from intact at flexion angles between 30° and 50° (p>.32). There were no significant differences between the two reconstruction conditions (p=.74). This study showed that there was no difference in the TF kinematics or compressive stresses between SB- and DB-ACLR, and only minor differences when compared to the intact state. PMID:21696962

  17. Do early quadriceps exercises affect the outcome of ACL reconstruction? A randomised controlled trial.

    PubMed

    Shaw, Triston; Williams, Marie T; Chipchase, Lucy S

    2005-01-01

    A prospective, blinded, randomised controlled trial investigated the effectiveness of quadriceps exercises following anterior cruciate ligament reconstruction. A treatment group (Quadriceps exercise group) performed straight leg raises and isometric quadriceps contractions throughout the first two postoperative weeks, and a second group (No quadriceps exercise group) did not. A battery of outcome measures assessed subjects postoperatively at day one, two weeks, and one, three and six months. A total of 103 patients (Quadriceps exercise n = 48, No quadriceps exercise n = 55) commenced the study with 91 subjects available at final follow up (Quadriceps exercise n = 47, No quadriceps exercise n = 44). Performance of quadriceps exercises significantly improved a number of knee flexion and extension range of motion measurements (p = 0.01 to 0.04). No significant differences were found between the two groups at any postoperative period for quadriceps lag (p = 0.36), functional hop testing (p = 0.49 to 0.51), isokinetic quadriceps strength (p = 0.70 to 0.72), the majority of numerical analogue scores (p = 0.1 to 0.94) and Cincinnati scores (p = 0.10 to 0.84). Subjects performing quadriceps exercises reported significantly higher pain scores with exercise on the first postoperative day (p = 0.02). At six months postoperatively, the Quadriceps exercise subjects reported significantly more favourable Cincinnati scores for symptoms (p = 0.005) and problems with sport (p = 0.05). While average knee laxity was not significantly different between treatment groups over time (p = 0.27 to 0.94), quadriceps exercise performance was associated with a significantly lower incidence of abnormal knee laxity. Isometric quadriceps exercises and straight leg raises can be safely prescribed during the first two postoperative weeks and confer advantages for faster recovery of knee range of motion and stability. It remains to be proven whether the magnitude of differences between groups is

  18. Predictors of Revision Surgery After Primary Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Yabroudi, Mohammad A.; Björnsson, Haukur; Lynch, Andrew D.; Muller, Bart; Samuelsson, Kristian; Tarabichi, Majd; Karlsson, Jón; Fu, Freddie H.; Harner, Christopher D.; Irrgang, James J.

    2016-01-01

    Background: Revision anterior cruciate ligament (ACL) reconstruction surgery occurs in 5% to 15% of individuals undergoing ACL reconstruction. Identifying predictors for revision ACL surgery is of essence in the pursuit of creating adequate prevention programs and to identify individuals at risk for reinjury and revision. Purpose: To determine predictors of revision ACL surgery after failed primary ACL reconstruction. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 251 participants (mean age ± SD, 26.1 ± 9.9 years) who had undergone primary ACL reconstruction 1 to 5 years earlier completed a comprehensive survey to determine predictors of revision ACL surgery at a mean 3.4 ± 1.3 years after the primary ACL reconstruction. Potential predictors that were assessed included subject characteristics (age at the time of surgery, time from injury to surgery, sex, body mass index, preinjury activity level, return to sport status), details of the initial injury (mechanism; concomitant injury to other ligaments, menisci, and cartilage), surgical details of the primary reconstruction (Lachman and pivot shift tests under anesthesia, graft type, femoral drilling technique, reconstruction technique), and postoperative course (length of rehabilitation, complications). Univariate and multivariate logistic regression analyses were performed to identify factors that predicted the need for revision ACL surgery. Results: Overall, 21 (8.4%) subjects underwent revision ACL surgery. Univariate analysis showed that younger age at the time of surgery (P = .003), participation in sports at a competitive level (P = .023), and double-bundle ACL reconstruction (P = .024) predicted increased risk of revision ACL surgery. Allograft reconstructions also demonstrated a trend toward greater risk of revision ACL surgery (P = .076). No other variables were significantly associated with revision ACL surgery. Multivariate analysis revealed that revision ACL surgery was

  19. Are Articular Cartilage Lesions and Meniscus Tears Predictive of IKDC, KOOS, and Marx Activity Level Outcomes after ACL Reconstruction? A 6-Year Multicenter Cohort Study

    PubMed Central

    Cox, Charles L.; Huston, Laura J.; Dunn, Warren R.; Reinke, Emily K.; Nwosu, Samuel K.; Parker, Richard D.; Wright, Rick W.; Kaeding, Christopher C.; Marx, Robert G.; Amendola, Annunziata; McCarty, Eric C.; Wolf, Brian R.; Harrell, Frank E.; Spindler, Kurt P.

    2014-01-01

    Background Identifying risk factors for inferior outcomes after ACL reconstruction (ACLR) is important for prognosis and future treatment. The goal of this study was to determine whether articular cartilage and meniscal variables are predictive of 3 validated sports outcome instruments after ACLR. Hypothesis/Purpose We hypothesized that articular cartilage lesions and meniscus tears/treatment would be predictors of the IKDC, KOOS (all 5 subscales), and Marx activity level at 6 years following ACLR. Study Design Prospective cohort, Level 1 Methods Between 2002 and 2004, 1512 ACLR subjects were prospectively enrolled and followed longitudinally with the IKDC, KOOS, and Marx activity score completed at entry, 2, and 6 years. A logistic regression model was built incorporating variables from patient demographics, surgical technique, articular cartilage injuries, and meniscus tears/treatment to determine the predictors (risk factors) of IKDC, KOOS, and Marx at 6 years. Results We completed a minimum follow-up on 86% (1307/1512) of our cohort at 6 years. The cohort was 56% male, had a median age of 23 years at the time of enrollment, with 76% reporting a non-contact injury mechanism. Incidence of concomitant pathology at the time of surgery consisted of the following: articular cartilage (medial femoral condyle [MFC]-25%, lateral femoral condyle [LFC]-20%, medial tibial plateau [MTP]-6%, lateral tibial plateau [LTP]-12%, patella-20%, trochlear-9%) and meniscal (medial-38%, lateral-46%). Both articular cartilage lesions and meniscal tears were significant predictors of 6-year outcomes on IKDC and KOOS. Grade 3 or 4 articular cartilage lesions (excluding patella) significantly reduced IKDC and KOOS scores at 6 years. IKDC demonstrated worse outcomes with the presence of a grade 3-4 chondral lesion on the MFC, MTP, and LFC. Likewise, KOOS was negatively affected by cartilage injury. The sole significant predictor of reduced Marx activity was the presence of a grade 4 lesion

  20. Anteromedial portal versus transtibial drilling techniques in ACL reconstruction: a blinded cross-sectional study at two- to five-year follow-up

    PubMed Central

    Alentorn-Geli, Eduard; Samitier, Gonzalo; Álvarez, Pedro; Steinbacher, Gilbert

    2010-01-01

    Drilling of the femoral tunnel with the transtibial (TT) technique is widely used in bone-patellar tendon-bone (BPTB) anterior cruciate ligament (ACL) reconstruction. Recent studies suggest higher knee stability with the use of the anteromedial portal (AMP). The purpose of this study was to compare functional and clinical outcomes of BPTB ACL reconstruction using the TT or the AMP technique for drilling the femoral tunnel. All ACL reconstructions between January 2003 and April 2006 were approached for eligibility. Forty-seven patients met inclusion criteria (21 TT group and 26 AMP group). Blinded assessments of IKDC score, knee stability and range of motion, one-leg hop test, mid-quadriceps circumference, VAS for satisfaction with surgery, Lysholm and Tegner scores, and SF-12 questionnaire were obtained for both groups. Data on preoperative and postoperative surgical timing were retrospectively reviewed through the charts. The AMP group demonstrated a significantly lower recovery time from surgery to walking without crutches (p < 0.01), to return to normal life (p < 0.03), to return jogging (p < 0.03), to return training (p < 0.03), and to return to play (p < 0.03). Knee stability values measured with KT-1000, Lachman test, pivot-shift sign, and objective IKDC score assessments were significantly better for the AMP compared to TT group (p < 0.002, p < 0.03, p < 0.02, p < 0.015, respectively). No differences were found for VAS for satisfaction with surgery, Lysholm, Tegner, and SF-12 between both groups. The use of the AMP technique significantly improved the anterior-posterior and rotational knee stability, IKDC scores, and recovery time from surgery compared to the TT technique. PMID:20401753

  1. Anteromedial portal versus transtibial drilling techniques in ACL reconstruction: a blinded cross-sectional study at two- to five-year follow-up.

    PubMed

    Alentorn-Geli, Eduard; Samitier, Gonzalo; Alvarez, Pedro; Steinbacher, Gilbert; Cugat, Ramón

    2010-06-01

    Drilling of the femoral tunnel with the transtibial (TT) technique is widely used in bone-patellar tendon-bone (BPTB) anterior cruciate ligament (ACL) reconstruction. Recent studies suggest higher knee stability with the use of the anteromedial portal (AMP). The purpose of this study was to compare functional and clinical outcomes of BPTB ACL reconstruction using the TT or the AMP technique for drilling the femoral tunnel. All ACL reconstructions between January 2003 and April 2006 were approached for eligibility. Forty-seven patients met inclusion criteria (21 TT group and 26 AMP group). Blinded assessments of IKDC score, knee stability and range of motion, one-leg hop test, mid-quadriceps circumference, VAS for satisfaction with surgery, Lysholm and Tegner scores, and SF-12 questionnaire were obtained for both groups. Data on preoperative and postoperative surgical timing were retrospectively reviewed through the charts. The AMP group demonstrated a significantly lower recovery time from surgery to walking without crutches (p < 0.01), to return to normal life (p < 0.03), to return jogging (p < 0.03), to return training (p < 0.03), and to return to play (p < 0.03). Knee stability values measured with KT-1000, Lachman test, pivot-shift sign, and objective IKDC score assessments were significantly better for the AMP compared to TT group (p < 0.002, p < 0.03, p < 0.02, p < 0.015, respectively). No differences were found for VAS for satisfaction with surgery, Lysholm, Tegner, and SF-12 between both groups. The use of the AMP technique significantly improved the anterior-posterior and rotational knee stability, IKDC scores, and recovery time from surgery compared to the TT technique. PMID:20401753

  2. Whole Body Vibration Exercise Protocol versus a Standard Exercise Protocol after ACL Reconstruction: A Clinical Randomized Controlled Trial with Short Term Follow-Up

    PubMed Central

    Berschin, Gereon; Sommer, Björn; Behrens, Antje; Sommer, Hans-Martin

    2014-01-01

    The suitability and effectiveness of whole body vibration (WBV) exercise in rehabilitation after injury of the anterior cruciate ligament (ACL) was studied using a specially designed WBV protocol. We wanted to test the hypothesis if WBV leads to superior short term results regarding neuromuscular performance (strength and coordination) and would be less time consuming than a current standard muscle strengthening protocol. In this prospective randomized controlled clinical trial, forty patients who tore their ACL and underwent subsequent ligament reconstruction were enrolled. Patients were randomized to the whole body vibration (n=20) or standard rehabilitation exercise protocol (n=20). Both protocols started in the 2nd week after surgery. Isometric and isokinetic strength measurements, clinical assessment, Lysholm score, neuromuscular performance were conducted weeks 2, 5, 8 and 11 after surgery. Time spent for rehabilitation exercise was reduced to less than a half in the WBV group. There were no statistically significant differences in terms of clinical assessment, Lysholm score, isokinetic and isometric strength. The WBV group displayed significant better results in the stability test. In conclusion, preliminary data indicate that our whole body vibration muscle exercise protocol seems to be a good alternative to a standard exercise program in ACL-rehabilitation. Despite of its significant reduced time requirement it is at least equally effective compared to a standard rehabilitation protocol. Key points In this prospective randomized controlled clinical trial, we tested the hypothesis if WBV leads to superior short term results regarding neuromuscular performance (strength and coordination) and would be less time consuming than a current standard muscle strengthening protocol in forty patients who underwent ACL reconstruction. Time spent for rehabilitation exercise was reduced to less than a half in the WBV group as compared to the standard exercise group. Both

  3. ACL reconstruction - discharge

    MedlinePlus

    ... sleeping without the brace and removing it for showers. When the brace is off for any reason, ... dressing and bandage clean and dry . You can shower again after your dressing is removed. When you ...

  4. Outcome of combined autologous chondrocyte implantation and anterior cruciate ligament reconstruction

    PubMed Central

    Dhinsa, Baljinder S; Nawaz, Syed Z; Gallagher, Kieran R; Skinner, John; Briggs, Tim; Bentley, George

    2015-01-01

    Background: Instability of the knee joint, after anterior cruciate ligament (ACL) injury, is contraindication to osteochondral defect repair. This prospective study is to investigate the role of combined autologous chondrocyte implantation (ACI) with ACL reconstruction. Materials and Methods: Three independent groups of patients with previous ACL injuries undergoing ACI were identified and prospectively followed up. The first group had ACI in combination with ACL reconstruction (combined group); the 2nd group consisted of individuals who had an ACI procedure having had a previously successful ACL reconstruction (ACL first group); and the third group included patients who had an ACI procedure to a clinically stable knee with documented nonreconstructed ACL disruption (No ACL group). Their outcomes were assessed using the modified cincinnati rating system, the Bentley functional (BF) rating system (BF) and a visual analog scale (VAS). Results: At a mean followup of 64.24 months for the ACL first group, 63 months for combined group and 78.33 months for the No ACL group; 60% of ACL first patients, 72.73% of combined group and 83.33% of the No ACL group felt their outcome was better following surgery. There was no significant difference demonstrated in BF and VAS between the combined and ACL first groups. Results revealed a significant affect of osteochondral defect size on outcome measures. Conclusion: The study confirms that ACI in combination with ACL reconstruction is a viable option with similar outcomes as those patients who have had the procedures staged. PMID:26015603

  5. Early versus late start of open kinetic chain quadriceps exercises after ACL reconstruction with patellar tendon or hamstring grafts: a prospective randomized outcome study.

    PubMed

    Heijne, Annette; Werner, Suzanne

    2007-04-01

    The purpose of the present investigation was to evaluate physical outcome after anterior cruciate ligament (ACL) reconstruction with early versus late initiation of open kinetic chain (OKC) exercises for the quadriceps in patients operated on either patellar tendon or hamstring grafts. Sixty-eight patients, 36 males and 32 females, with either patellar tendon graft (34 patients) or hamstring graft (34 patients) were enrolled in this study. All patients were randomly allocated to either early (the 4th postoperative week) or late (the 12th postoperative week) start of OKC exercises for the quadriceps, resulting in four subgroups: patellar tendon reconstruction, early start (P4) or late start (P12) of OKC quadriceps exercises, hamstring tendon reconstruction, early start (H4) or late start (H12) of quadriceps OKC exercises. Prior to surgery and 3, 5 and 7 months later, assessments of range of motion (goniometer), anterior knee laxity (KT-1000), postural sway (KAT 2000), thigh muscle torques (Kin-Com dynamometer) and anterior knee pain (anterior knee pain score) were evaluated. No significant group differences were found in terms of range of motion 3, 5 and 7 months postoperatively. The H4 group showed a significantly higher mean difference of laxity over time of 1.0 mm (CI: 0.18-1.86) than the P4 group (P=0.04). Within the same type of surgery, the H4 against the H12, the mean difference over time was 1.2 mm (0.37-2.1) higher in the H4 group than in the H12 group (P=0.01). There were no significant group differences in terms of postural sway or anterior knee pain at the different test occasions. Significant differences in trends (changes over time) were found when comparing the four groups, for both quadriceps muscle torques (P<0.001) and hamstring muscle torques (P<0.001). All groups, except the P4 group, reached preoperative values of quadriceps muscle torques at the 7 months follow-up. In the H4 and the H12 groups, significantly lower hamstring muscle torques at

  6. Comparison of traditional advanced cardiac life support (ACLS) course instruction vs. a scenario-based, performance oriented team instruction (SPOTI) method for Korean paramedic students.

    PubMed

    Lee, Christopher C; Im, Mark; Kim, Tae Min; Stapleton, Edward R; Kim, Kyuseok; Suh, Gil Joon; Singer, Adam J; Henry, Mark C

    2010-01-01

    Current Advanced Cardiac Life Support (ACLS) course instruction involves a 2-day course with traditional lectures and limited team interaction. We wish to explore the advantages of a scenario-based performance-oriented team instruction (SPOTI) method to implement core ACLS skills for non-English-speaking international paramedic students. The objective of this study was to determine if scenario-based, performance-oriented team instruction (SPOTI) improves educational outcomes for the ACLS instruction of Korean paramedic students. Thirty Korean paramedic students were randomly selected into two groups. One group of 15 students was taught the traditional ACLS course. The other 15 students were instructed using a SPOTI method. Each group was tested using ACLS megacode examinations endorsed by the American Heart Association. All 30 students passed the ACLS megacode examination. In the traditional ACLS study group an average of 85% of the core skills were met. In the SPOTI study group an average of 93% of the core skills were met. In particular, the SPOTI study group excelled at physical examination skills such as airway opening, assessment of breathing, signs of circulation, and compression rates. In addition, the SPOTI group performed with higher marks on rhythm recognition compared to the traditional group. The traditional group performed with higher marks at providing proper drug dosages compared to the SPOTI students. However, the students enrolled in the SPOTI method resulted in higher megacode core compliance scores compared to students trained in traditional ACLS course instruction. These differences did not achieve statistical significance due to the small sample size.

  7. Sterilization with electron beam irradiation influences the biomechanical properties and the early remodeling of tendon allografts for reconstruction of the anterior cruciate ligament (ACL).

    PubMed

    Schmidt, Tanja; Hoburg, Arnd; Broziat, Christine; Smith, Mark D; Gohs, Uwe; Pruss, Axel; Scheffler, Sven

    2012-08-01

    Although allografts for anterior cruciate ligament (ACL) replacement have shown advantages compared to autografts, their use is limited due to the risk of disease transmission and the limitations of available sterilization methods. Gamma sterilization has shown detrimental effects on graft properties at the high doses required for sufficient pathogen inactivation. In our previous in vitro study on human patellar tendon allografts, Electron beam (Ebeam) irradiation showed less detrimental effects compared to gamma sterilization (Hoburg et al. in Am J Sports Med 38(6):1134-1140, 2010). To investigate the biological healing and restoration of the mechanical properties of a 34 kGy Ebeam treated tendon allograft twenty-four sheep underwent ACL replacement with either a 34 kGy Ebeam treated allograft or a non-sterilized fresh frozen allograft. Biomechanical testing of stiffness, ultimate failure load and AP-laxity as well as histological analysis to investigate cell, vessel and myofibroblast-density were performed after 6 and 12 weeks. Native sheep ACL and hamstring tendons (HAT, each n = 9) served as controls. The results of a previous study analyzing the remodeling of fresh frozen allografts (n = 12) and autografts (Auto, n = 18) with the same study design were also included in the analysis. Statistics were performed using Mann-Whitney U test followed by Bonferroni-Holm correction. Results showed significantly decreased biomechanical properties during the early remodeling period in Ebeam treated grafts and this was accompanied with an increased remodeling activity. There was no recovery of biomechanical function from 6 to 12 weeks in this group in contrast to the results observed in fresh frozen allografts and autografts. Therefore, high dose Ebeam irradiation investigated in this paper cannot be recommended for soft tissue allograft sterilization.

  8. ACL-Injured Subjects Have Smaller ACLs Than Matched Controls: An MRI Study

    PubMed Central

    Chaudhari, Ajit M.W.; Zelman, Eric A.; Flanigan, David C.; Kaeding, Christopher C.; Nagaraja, Haikady N.

    2013-01-01

    Background Very few studies examining the predisposing anatomical factors leading to anterior cruciate ligament (ACL) injuries have examined the ACL itself, and none of these directly examined the difference in ACL properties between injured and matched control subjects. Hypothesis ACL total volume of people who have experienced a non-contact ACL injury is smaller than that of matched controls. Methods Contours of the ACL were manually identified in sagittal MR images and volumes were calculated for 27 contralateral, healthy knees of individuals after non-contact ACL injury and for 27 control subjects matched for gender, height, age, and weight. Validation of this method was performed on 5 porcine knees. Stepwise multiple regression was used to determine the difference in ACL volume between injured and control subjects while considering gender, height, weight, and age as potential covariates. Results Contralateral ACL volume for injured subjects was significantly smaller than non-injured subjects (p=0.0208) by 231 mm3 after adjusting for weight, which was also a significant contributor to ACL volume (p<0.0001). At the average body mass of 72.7kg, subjects with a non-contact ACL injury had an average contralateral ACL volume of 1921 mm3, while the corresponding control group had an average volume of 2151 mm3. Gender, height, and age were not significant when weight was included in the regression model. Conclusions This study shows that there are anthropometric differences between the knees of subjects with a non-contact ACL injury and those without an ACL injury, suggesting that ACL volume may play a direct role in non-contact ACL injury. PMID:19307330

  9. Does Gracilis Tendon Harvest During ACL Reconstruction with a Hamstring Autograft Affect Torque of Muscles Responsible for Shin Rotation?

    PubMed Central

    Królikowska, Aleksandra; Czamara, Andrzej; Kentel, Maciej

    2015-01-01

    Background A growing body of evidence indicates that in patients after anterior cruciate ligament reconstruction (ACLR) with a combined semitendinosus and gracilis (STGR) graft there are large deficits in the internal rotation strength, which has led some authors to recommend harvest of only ST tendon whenever possible. The purpose of this study was to assess the isometric (IT) and peak torque (PT) of the muscles responsible for shin rotation in patients after ACLR with an ST or with an STGR graft. Material/Methods Twenty patients with an ST graft and 20 patients with a combined STGR graft underwent a 6-month postoperative rehabilitation program after ACLR. At the end of the rehabilitation program, the IT and PT of the muscles responsible for internal (IR) and external rotation (ER) of the shin were measured. The results were compared to the results of a control group. Additionally, to determine the reliability of the dynamometer for clinical research, a test-retest assessment was performed. Results There were no statistically significant differences between the 3 groups of participants. Nevertheless, in the STGR group there was a statistically significant difference between the IT of muscles internally rotating the shin in the involved knee and uninvolved knee at 25° of the internal shin rotation. Conclusions Comparison of IT and PT measurements performed after 24 weeks of postoperative rehabilitation generally showed no differences between patients after ACLR with the use of ST graft and patients who received a combination graft consisting of STGR. Nevertheless, there was an influence of GR harvest on internal shin rotation torque at a deep internal rotation angle. PMID:26190033

  10. Enhancement of tendon-bone healing for anterior cruciate ligament (ACL) reconstruction using bone marrow-derived mesenchymal stem cells infected with BMP-2.

    PubMed

    Dong, Yu; Zhang, Qingguo; Li, Yunxia; Jiang, Jia; Chen, Shiyi

    2012-10-22

    At present, due to the growing attention focused on the issue of tendon-bone healing, we carried out an animal study of the use of genetic intervention combined with cell transplantation for the promotion of this process. Here, the efficacy of bone marrow stromal cells infected with bone morphogenetic protein-2 (BMP-2) on tendon-bone healing was determined. A eukaryotic expression vector containing the BMP-2 gene was constructed and bone marrow-derived mesenchymal stem cells (bMSCs) were infected with a lentivirus. Next, we examined the viability of the infected cells and the mRNA and protein levels of BMP-2-infected bMSCs. Gastrocnemius tendons, gastrocnemius tendons wrapped by bMSCs infected with the control virus (bMSCs+Lv-Control), and gastrocnemius tendons wrapped by bMSCs infected with the recombinant BMP-2 virus (bMSCs+Lv-BMP-2) were used to reconstruct the anterior cruciate ligament (ACL) in New Zealand white rabbits. Specimens from each group were harvested four and eight weeks postoperatively and evaluated using biomechanical and histological methods. The bMSCs were infected with the lentivirus at an efficiency close to 100%. The BMP-2 mRNA and protein levels in bMSCs were significantly increased after lentiviral infection. The bMSCs and BMP-2-infected bMSCs on the gastrocnemius tendon improved the biomechanical properties of the graft in the bone tunnel; specifically, bMSCs infected with BMP-2 had a positive effect on tendon-bone healing. In the four-week and eight-week groups, bMSCs+Lv-BMP-2 group exhibited significantly higher maximum loads of 29.3 ± 7.4 N and 45.5 ± 11.9 N, respectively, compared with the control group (19.9 ± 6.4 N and 21.9 ± 4.9 N) (P = 0.041 and P = 0.001, respectively). In the eight-week groups, the stiffness of the bMSCs+Lv-BMP-2 group (32.5 ± 7.3) was significantly higher than that of the bMSCs+Lv-Control group (22.8 ± 7.4) or control groups (12.4 ± 6.0) (p = 0.036 and 0.001, respectively). Based on the histological

  11. The effect of neuromuscular electrical stimulation on quadriceps strength and knee function in professional soccer players: return to sport after ACL reconstruction.

    PubMed

    Taradaj, J; Halski, T; Kucharzewski, M; Walewicz, K; Smykla, A; Ozon, M; Slupska, L; Dymarek, R; Ptaszkowski, K; Rajfur, J; Pasternok, M

    2013-01-01

    The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction) on the quadriceps muscle. The 80 participants (NMES = 40, control = 40) received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500 Hz, and train of pulses frequency: 50 Hz) three times daily (3 hours of break between treatments), 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months) were applied. The results of this study show that NMES (in presented parameters in experiment) is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741.

  12. Indian hedgehog signaling and the role of graft tension in tendon-to-bone healing: Evaluation in a rat ACL reconstruction model.

    PubMed

    Carbone, Andrew; Carballo, Camila; Ma, Richard; Wang, Hongsheng; Deng, Xianghua; Dahia, Chitra; Rodeo, Scott

    2016-04-01

    The structure and composition of the native enthesis is not recapitulated following tendon-to-bone repair. Indian Hedgehog (IHH) signaling has recently been shown to be important in enthesis development in a mouse model but no studies have evaluated IHH signaling in a healing model. Fourteen adult male rats underwent ACL reconstruction using a flexor tendon graft. Rats were assigned to two groups based on whether or not they received 0N or 10N of pre-tension of the graft. Specimens were evaluated at 3 and 6 weeks post-operatively using immunohistochemistry for three different protein markers of IHH signaling. Quantitative analysis of staining area and intensity using custom software demonstrated that IHH signaling was active in interface tissue formed at the healing tendon-bone interface. We also found increased staining area and intensity of IHH signaling proteins at 3 weeks in animals that received a pre-tensioned tendon graft. No significant differences were seen between the 3-week and 6-week time points. Our data suggests that the IHH signaling pathway is active during the tendon-bone healing process and appears to be mechanosensitive, as pre-tensioning of the graft at the time of surgery resulted in increased IHH signaling at three weeks. PMID:26447744

  13. The Effect of NeuroMuscular Electrical Stimulation on Quadriceps Strength and Knee Function in Professional Soccer Players: Return to Sport after ACL Reconstruction

    PubMed Central

    Taradaj, J.; Halski, T.; Kucharzewski, M.; Walewicz, K.; Smykla, A.; Ozon, M.; Slupska, L.; Dymarek, R.; Ptaszkowski, K.; Rajfur, J.; Pasternok, M.

    2013-01-01

    The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction) on the quadriceps muscle. The 80 participants (NMES = 40, control = 40) received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500 Hz, and train of pulses frequency: 50 Hz) three times daily (3 hours of break between treatments), 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months) were applied. The results of this study show that NMES (in presented parameters in experiment) is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741. PMID:24381943

  14. Septic arthritis following anterior cruciate ligament reconstruction using tendon allografts--Florida and Louisiana, 2000.

    PubMed

    2001-12-01

    In the United States, approximately 50,000 knee surgeries are performed each year for repairing anterior cruciate ligament (ACL) injuries. Tissue allografts frequently are used for ACL reconstruction, and septic arthritis is a rare complication of such procedures. This report describes four patients who acquired postsurgical septic arthritis probably associated with contaminated bone-tendon-bone allografts used for ACL reconstruction. Effective sterilization methods that do not functionally alter musculoskeletal tissue are needed to prevent allograft-related infections.

  15. Septic arthritis following anterior cruciate ligament reconstruction using tendon allografts--Florida and Louisiana, 2000.

    PubMed

    2001-12-01

    In the United States, approximately 50,000 knee surgeries are performed each year for repairing anterior cruciate ligament (ACL) injuries. Tissue allografts frequently are used for ACL reconstruction, and septic arthritis is a rare complication of such procedures. This report describes four patients who acquired postsurgical septic arthritis probably associated with contaminated bone-tendon-bone allografts used for ACL reconstruction. Effective sterilization methods that do not functionally alter musculoskeletal tissue are needed to prevent allograft-related infections. PMID:11770503

  16. What I have learned about the ACL: utilizing a progressive rehabilitation scheme to achieve total knee symmetry after anterior cruciate ligament reconstruction.

    PubMed

    Shelbourne, K Donald; Klotz, Christine

    2006-05-01

    Anterior cruciate ligament surgery and rehabilitation have changed drastically during the past 30 years. The patellar tendon autograft fixed with buttons provides tight bone-to-bone placement of the graft and quick bony healing, which allows accelerated rehabilitation to obtain full range of motion and strength. Although surgical stability is easily reproducible, long-term patient satisfaction is difficult to guarantee. Full knee range of motion should be compared to that of the contralateral normal knee, including full hyperextension. We followed the progress of all patients to gauge the utility of our rehabilitation program. In order of importance, the lack of normal knee range of motion (within 2 degrees extension and 5 degrees of flexion compared with that of the normal knee), partial or total medial meniscectomy, partial or total lateral meniscectomy, and articular cartilage damage were related to lower subjective scores. Rehabilitation after ACL reconstruction must first strive to achieve full symmetrical knee range of motion before aggressive strengthening can begin. Our current perioperative rehabilitation starts at the time of injury and preoperatively includes aggressive swelling reduction, hyperextension exercises, gait training, and mental preparation. Goals after surgery are to control swelling while regaining full knee range of motion. After quadriceps strengthening goals are reached, patients can shift to sport-specific exercises. When using a graft from the contralateral knee, the conflicting goals of strengthening the donor site and achieving full knee range of motion are divided between the knees. Thus, normal range of motion and strength can be achieved more easily and more quickly than when using an ipsilateral graft. Regardless of the graft source, a systematic rehabilitation program that emphasizes the return to symmetrical knee motion, including hyperextension, is necessary to achieve the optimum result.

  17. Tripeptide-copper complex GHK-Cu (II) transiently improved healing outcome in a rat model of ACL reconstruction.

    PubMed

    Fu, Sai-Chuen; Cheuk, Yau-Chuk; Chiu, Wai-Yin Vivien; Yung, Shu-Hang; Rolf, Christer G; Chan, Kai-Ming

    2015-07-01

    After anterior cruciate ligament reconstruction (ACLR), the biological healing of the graft is a rate-limiting step which can contribute to graft failure. The tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu(II) (GHK-Cu) is a well-known activator of tissue remodeling. We investigated whether GHK-Cu can improve graft healing following ACLR. Seventy-two rats underwent unilateral ACLR were randomized to saline, 0.3 or 3 mg/ml GHK-Cu groups (n = 24). Post-operational intra-articular injections were given from week 2, once a week, for 4 weeks. Gait analysis was performed pre-injury and at harvesting time. At 6 or 12 weeks post-operation, knee specimens were harvested for knee laxity test, graft pull-out test, and histology. At 6 weeks post-ACLR, GHK-Cu groups resulted in a smaller side-to-side difference in knee laxity as compared to the saline group (p = 0.009), but there was no significant difference at 12 weeks post-operation. The graft complex in the 0.3 mg/ml GHK-Cu group had higher stiffness than saline group at 6 weeks post-operation (p = 0.026), but there was no significant difference in ultimate load, gait parameters, and histological scores among treatment groups. All grafts failed mid-substance during pull-out test. Intra-articular supplementation with a bioactive small molecule GHK-Cu improved graft healing following ACLR in rat, but the beneficial effects could not last as treatment discontinued. PMID:25731775

  18. The relationship between subjective knee scores, isokinetic testing, and functional testing in the ACL-reconstructed knee.

    PubMed

    Wilk, K E; Romaniello, W T; Soscia, S M; Arrigo, C A; Andrews, J R

    1994-08-01

    It is important to examine the functional relationships between commonly performed clinical tests and to resolve inconsistencies in previous investigative results. The purpose of this study was to determine if a correlation exists between three commonly performed clinical tests: isokinetic isolated knee concentric muscular testing, the single-leg hop test, and the subjective knee score in anterior cruciate ligament reconstructed knees. To determine if a relationship exists would be beneficial to clinicians in determining patient progression, treatment modification, and return-to-sport objective parameters. Several investigators have analyzed two of these parameters, but no one has investigated three parameters to date. Additionally, this study explored the concept of limb acceleration and deceleration during high-speed isokinetics and its relationship to function. Fifty patients were randomly selected (29 males) with a mean age of 23.7 years (range 15-52). The subjects completed a subjective knee score questionnaire that rated symptoms (pain, swelling, giving way) and specific sport function and completed an overall knee score assessment. The patients were then evaluated performing three one-legged functional tests: 1) hop for distance, 2) timed hop, and 3) cross-over triple hop. Isokinetic testing was performed on a Biodex dynamometer at 180, 300, and 450 degrees/sec for knee extension/flexion. The patients' mean value of the self-assessed knee rating was 86 points. Sixty-four percent of the patients exhibited normal limb symmetry (within 85%) on all three single-leg hop tests. Sixteen percent exhibited quadriceps strength at least 90% of the contralateral limb isokinetically. A positive correlation was noted between isokinetic knee extension peak torque (180, 300 degrees/sec) and subjective knee scores, and the three hop tests (p < 0.001). A statistical trend was noted between knee extension acceleration and deceleration range at 180 and 300 degrees/sec for the

  19. Restriction in Hip Internal Rotation is Associated with an Increased Risk of ACL Injury in NFL Combine Athletes: A Clinical and Biomechanical Study

    PubMed Central

    Bedi, Asheesh; Warren, Russell F.; Oh, Youkeun K.; Wojtys, Edward M.; Oltean, Hanna N.; Ashton-Miller, James A.; Kelly, Bryan T.

    2013-01-01

    Objectives: A deficiency in hip internal rotation secondary to femoroacetabular impingement (FAI) may result in compensatory increases in rotational stresses applied to the ACL with cutting and pivoting activities, thereby increasing the risk of ACL failure in athletes. The purpose of this study was to correlate ACL injury with hip range of motion in a consecutive series of elite, contact athletes and to test the hypothesis that a restriction in the available hip axial rotation in a dynamic in silico model of a simulated pivot landing would increase ACL strain and the risk of ACL rupture. Methods: We examined 324 football athletes attending the 2012 NFL National Invitational Camp. Hip range of internal rotation was measured by three orthopaedic surgeons and correlated with a history of ACL injury and surgical repair using generalized estimating equation logistic regression analysis. An in silico biomechanical model was used to study the effect of FAI on the peak relative ACL strain developed during a simulated pivot landing. Results: The in vivo results demonstrated that a reduction in internal rotation of the left hip was associated with a statistically significant increased odds of ACL injury in the ipsilateral or contralateral knee (OR = 0.95, P =.0001 and P < .0001, respectively). A post-estimation calculation of odds ratio for ACL injury based on deficiency in hip internal rotation demonstrated that a 30-degree reduction in left hip internal rotation was associated with 4.06 and 5.29 times greater odds of ACL injury in the ipsilateral and contralateral limbs, respectively (Figure 1A). The in silico model demonstrated that FAI systematically increased the peak ACL strain predicted during the pivot landing (Figure 1B). The peak AM-ACL strain for 5-degrees of internal rotation was 22.5% greater than the corresponding value for 10-degrees of internal rotation (i.e., a peak AM-ACL strain of 5.77% vs. 4.71%, respectively). Conclusion: FAI may significantly increase

  20. Repaired ACL More Likely to Tear Again in Young Women

    MedlinePlus

    ... risk for a repeat tear of the knee's anterior cruciate ligament (ACL) after surgery to repair it, a new study says. The study included just over 500 male and female athletes who underwent ACL reconstruction with a hamstring graft and were followed for ...

  1. An integrated approach to change the outcome part I: neuromuscular screening methods to identify high ACL injury risk athletes.

    PubMed

    Myer, Gregory D; Ford, Kevin R; Brent, Jensen L; Hewett, Timothy E

    2012-08-01

    An important step for treatment of a particular injury etiology is the appropriate application of a treatment targeted to the population at risk. An anterior cruciate ligament (ACL) injury risk algorithm has been defined that employs field-based techniques in lieu of laboratory-based motion analysis systems to identify athletes with high ACL injury risk landing strategies. The resultant field-based assessment techniques, in combination with the developed prediction algorithm, allow for low-cost identification of athletes who may be at increased risk of sustaining ACL injury. The combined simplicity and accuracy of the field-based tool facilitate its use to identify specific factors that may increase risk of injury in female athletes. The purpose of this report is to demonstrate novel algorithmic techniques to accurately capture and analyze measures of knee valgus motion, knee flexion range of motion, body mass, tibia length and quadriceps to hamstrings ratio with video analysis software typically used by coaches, strength and conditioning specialists, and athletic trainers. The field-based measurements and software analyses were used in a prediction algorithm to identify those at potential risk of noncontact ACL injury that may directly benefit from neuromuscular training.

  2. Arthroscopic anatomical double bundle anterior cruciate ligament reconstruction: A prospective longitudinal study

    PubMed Central

    Devgan, Ashish; Singh, Amanpreet; Gogna, Paritosh; Singla, Rohit; Magu, Narender Kumar; Mukhopadhyay, Reetadyuti

    2015-01-01

    Background: Single bundle anterior cruciate ligament (ACL) reconstruction has been the current standard of treatment for ACL deficiency. However, a significant subset of patients continue to report residual symptoms of instability with a poor pivot control. Cadaveric biomechanical studies have shown double bundle (DB) ACL reconstructions to restore the knee kinematics better. This study evaluates the outcome of DB ACL reconstruction. Materials and Methods: 30 consecutive patients who underwent anatomic DB ACL reconstruction were included in this prospective longitudinal study. There were all males with a mean age of 25 ± 7.45 years. All patients were prospectively evaluated using GeNouRoB (GNRB) arthrometer, functional knee scores (International Knee Documentation Committee [IKDC] and Lysholm) and postoperative magnetic resonance imaging (MRI) for comparing the graft orientation and footprint of the reconstructed ACL with that of the normal knee. Results: The average followup was 36.2 months. At the time of final followup the mean Lysholm score was 93.13 ± 3.31. As per the objective IKDC score, 26 patients (86.6%) were in Group A while 4 patients (13.3%) were in Group B. The mean differential anterior tibial translation by GNRB, arthrometer was 1.07 ± 0.8 mm (range 0.1-2.3 mm). All cases had a negative pivot shift test. MRI scans of operated and the contralateral normal knee showed the mean sagittal ACL tibial angle coronal ACL tibial angle and tibial ACL footprint to be in accordance with the values of the contralateral, normal knee. Conclusion: The study demonstrates that DB ACL reconstruction restores the ACL anatomically in terms of size and angle of orientation. However, long term studies are needed to further substantiate its role in decreasing the incidence of early osteoarthritic changes compared to the conventional single bundle reconstructions. PMID:26015600

  3. Adolescent ACL injury: treatment considerations.

    PubMed

    Pavlovich, Raymond; Goldberg, Steven H; Bach, Bernard R

    2004-04-01

    Anterior cruciate ligament (ACL) injury in a skeletally immature patient presents unique treatment challenges. In many cases, conservative treatment with bracing and physical therapy fails, resulting in recurrent instability, pain, swelling, and meniscal and chondral injury. The goal of surgical reconstruction is to recreate ACL stability without causing growth plate arrest, leg-length discrepancy, or angular deformity. Patient characteristics such as skeletal age, Tanner stage, onset of menses, family member height, growth spurt, recent change in foot size, and growth charts can help the surgeon approximate the degree of skeletal maturity and aid in selecting the timing and safest type of reconstruction. Numerous surgical techniques, ranging from an extra-articular reconstruction to intra-articular graft passage without physeal violation to standard transtibial and transfemoral tunnel placement with physeal violation, have been popularized. The majority of existing studies are retrospective case series, describing a particular author's specific technique experience. This article reviews the basic science and clinical literature, presents a treatment algorithm, and provides several case studies.

  4. Analytical Chemistry Laboratory (ACL) procedure compendium. Volume 2, Sample preparation methods

    SciTech Connect

    Not Available

    1993-08-01

    This volume contains the interim change notice for sample preparation methods. Covered are: acid digestion for metals analysis, fusion of Hanford tank waste solids, water leach of sludges/soils/other solids, extraction procedure toxicity (simulate leach in landfill), sample preparation for gamma spectroscopy, acid digestion for radiochemical analysis, leach preparation of solids for free cyanide analysis, aqueous leach of solids for anion analysis, microwave digestion of glasses and slurries for ICP/MS, toxicity characteristic leaching extraction for inorganics, leach/dissolution of activated metal for radiochemical analysis, extraction of single-shell tank (SST) samples for semi-VOC analysis, preparation and cleanup of hydrocarbon- containing samples for VOC and semi-VOC analysis, receiving of waste tank samples in onsite transfer cask, receipt and inspection of SST samples, receipt and extrusion of core samples at 325A shielded facility, cleaning and shipping of waste tank samplers, homogenization of solutions/slurries/sludges, and test sample preparation for bioassay quality control program.

  5. Analytical Chemistry Laboratory (ACL) procedure compendium. Volume 3, Inorganic instrumental methods

    SciTech Connect

    Not Available

    1993-08-01

    The methods cover: C in solutions, F (electrode), elements by atomic emission spectrometry, inorganic anions by ion chromatography, Hg in water/solids/sludges, As, Se, Bi, Pb, data calculations for SST (single shell tank?) samples, Sb, Tl, Ag, Pu, O/M ratio, ignition weight loss, pH value, ammonia (N), Cr(VI), alkalinity, U, C sepn. from soil/sediment/sludge, Pu purif., total N, water, C and S, surface Cl/F, leachable Cl/F, outgassing of Ge detector dewars, gas mixing, gas isotopic analysis, XRF of metals/alloys/compounds, H in Zircaloy, H/O in metals, inpurity extraction, reduced/total Fe in glass, free acid in U/Pu solns, density of solns, Kr/Xe isotopes in FFTF cover gas, H by combustion, MS of Li and Cs isotopes, MS of lanthanide isotopes, GC operation, total Na on filters, XRF spectroscopy QC, multichannel analyzer operation, total cyanide in water/solid/sludge, free cyanide in water/leachate, hydrazine conc., ICP-MS, {sup 99}Tc, U conc./isotopes, microprobe analysis of solids, gas analysis, total cyanide, H/N{sub 2}O in air, and pH in soil.

  6. Method for position emission mammography image reconstruction

    DOEpatents

    Smith, Mark Frederick

    2004-10-12

    An image reconstruction method comprising accepting coincidence datat from either a data file or in real time from a pair of detector heads, culling event data that is outside a desired energy range, optionally saving the desired data for each detector position or for each pair of detector pixels on the two detector heads, and then reconstructing the image either by backprojection image reconstruction or by iterative image reconstruction. In the backprojection image reconstruction mode, rays are traced between centers of lines of response (LOR's), counts are then either allocated by nearest pixel interpolation or allocated by an overlap method and then corrected for geometric effects and attenuation and the data file updated. If the iterative image reconstruction option is selected, one implementation is to compute a grid Siddon retracing, and to perform maximum likelihood expectation maiximization (MLEM) computed by either: a) tracing parallel rays between subpixels on opposite detector heads; or b) tracing rays between randomized endpoint locations on opposite detector heads.

  7. Patients With Isolated PCL Injuries Improve From Surgery as Much as Patients With ACL Injuries After 2 Years

    PubMed Central

    Owesen, Christian; Sivertsen, Einar Andreas; Engebretsen, Lars; Granan, Lars-Petter; Årøen, Asbjørn

    2015-01-01

    Background: Reports on outcome after posterior cruciate ligament (PCL) reconstruction often contain both isolated PCL and combined knee ligament injuries. This makes it difficult to conclude on the outcome after reconstruction of isolated PCL injuries. Purpose: To investigate the outcome after PCL reconstruction in patients with an isolated PCL injury and to compare this with the outcome of patients treated with reconstruction after isolated anterior cruciate ligament (ACL) injuries. Study Design: Cohort study; Level of evidence, 3. Methods: Seventy-one patients with an isolated PCL injury that was reconstructed surgically and who had registered in the Norwegian Knee Ligament Registry between 2004 and 2010 were included in this study. Patients with isolated ACL reconstructions (n = 9661) who had registered in the same period were included for comparison. Knee Injury and Osteoarthritis Outcome Score (KOOS) was used as the patient-reported outcome measure. Preoperative and 2-year postoperative KOOS scores were compared. Changes in KOOS score reported by the PCL patients were compared with changes reported by the ACL patients. Results: At the 2-year postoperative follow-up of the PCL-reconstructed patients, the patient-reported outcome was improved, measured by KOOS as follows: pain, 15.1 (95% CI, 8.5-21.8; P < .001); symptoms, 0.9 (95% CI, –6.6 to 8.3; P = .82); activities of daily living, 13.2 (95% CI, 6.6-13.9; P < .001); sports, 20.7 (95% CI, 11.8-29.4; P < .001); and quality of life, 26.6 (95% CI, 18.9-34.2; P < .001). According to the KOOS, the incremental improvements were similar for PCL and ACL patients. Time from injury to surgery was longer for the PCL patients compared with ACL patients (median, 21.5 vs 8.0 months; P < .001). Conclusion: Patients undergoing PCL reconstruction can expect the same improvements in KOOS score as patients undergoing ACL reconstruction. However, PCL patients start out with an inferior score on average and consequently end up

  8. Reconstructive methods in hearing disorders - surgical methods

    PubMed Central

    Zahnert, Thomas

    2005-01-01

    Restoration of hearing is associated in many cases with resocialisation of those affected and therefore occupies an important place in a society where communication is becoming ever faster. Not all problems can be solved surgically. Even 50 years after the introduction of tympanoplasty, the hearing results are unsatisfactory and often do not reach the threshold for social hearing. The cause of this can in most cases be regarded as incomplete restoration of the mucosal function of the middle ear and tube, which leads to ventilation disorders of the ear and does not allow real vibration of the reconstructed middle ear. However, a few are also caused by the biomechanics of the reconstructed ossicular chain. There has been progress in reconstructive middle ear surgery, which applies particularly to the development of implants. Implants made of titanium, which are distinguished by outstanding biocompatibility, delicate design and by biomechanical possibilities in the reconstruction of chain function, can be regarded as a new generation. Metal implants for the first time allow a controlled close fit with the remainder of the chain and integration of micromechanical functions in the implant. Moreover, there has also been progress in microsurgery itself. This applies particularly to the operative procedures for auditory canal atresia, the restoration of the tympanic membrane and the coupling of implants. This paper gives a summary of the current state of reconstructive microsurgery paying attention to the acousto-mechanical rules. PMID:22073050

  9. Mechanoreceptor Reinnervation of Autografts Versus Allografts After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Young, Simon W.; Valladares, Roberto D.; Loi, Florence; Dragoo, Jason L.

    2016-01-01

    Background: Loss of proprioceptive function occurs after anterior cruciate ligament (ACL) rupture. Clinical, motor, and proprioceptive function is known to improve after ACL reconstruction but does not return to normal. While histological studies of human ACL allografts have been unable to demonstrate mechanoreceptor reinnervation, animal data suggest that reinnervation may occur when an autograft is used. Purpose: To compare the presence or absence of mechanoreceptors between allograft versus autograft after ACL reconstruction in humans. Study Design: Cohort study; Level of evidence, 3. Methods: Ten patients with previous ACL reconstruction presenting for either revision ACL surgery or knee arthroscopy for other reasons were enrolled in a prospective, comparative study. Five patients had a previous autograft ACL and 5 patients had an allograft. Biopsies, either from intact or ruptured grafts, were taken from identical locations as close to the femoral and tibial insertions as possible. Specimens were stained with hematoxylin-eosin (H-E) and monoclonal antibodies against neurofilament protein (NFP), known to be present in mechanoreceptor tissue. Immunohistochemical examination was carried out, and the number of NFP+ neural tissue analogs was counted and compared with that of native ACL tissue. Results: The mean time between original graft and biopsy was 6.9 years (range, 0.5-15 years). Histological examination showed significantly less NFP+ neural analogs in allograft and autograft patients than control tissue (mean number of NFP+ analogs per high-power field, 0.7 ± 0.9 [allograft] and 0.5 ± 0.8 [autograft] vs 4.7 ± 0.9 [controls]; P < .0001). There was no significant difference in NFP analogs between autograft and allograft tissue. Conclusion: We found a reduced concentration of NFP+ neural analogs in ACL grafts compared with native ACL tissue. This deficit exists irrespective of whether allograft or autograft is used. These findings may explain the continued

  10. Multiresolution reconstruction method to optoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Patrickeyev, Igor; Oraevsky, Alexander A.

    2003-06-01

    A new method for reconstruction of optoacoustic images is proposed. The method of image reconstruction incorporates multiresolution wavelet filtering into spherical back-projection algorithm. According to our method, each optoacoustic signal detected with an array of ultrawide-band transducers is decomposed into a set of self-similar wavelets with different resolution (characteristic frequency) and then back-projected along the spherical traces for each resolution scale separately. The advantage of this approach is that one can reconstruct objects of a preferred size or a range of sizes. The sum of all images reconstructed with different resolutions yields an image that visualizes small and large objects at once. An approximate speed of the proposed algorithm is of the same order as algorithm, based on the Fast Fourier Transform (FFT). The accuracy of the proposed method is illustrated by images, which are reconstructed from simulated optoacoustic signals as well as signals measured with the Laser Optoacoustic Imaging System (LOIS) from a loop of blood vessel embedded in a gel phantom. The method can be used for contrast-enhanced optoacoustic imaging in the depth of tissue, i.e. for medical applications such as breast cancer or prostate cancer detection.

  11. PET Image Reconstruction Using Kernel Method

    PubMed Central

    Wang, Guobao; Qi, Jinyi

    2014-01-01

    Image reconstruction from low-count PET projection data is challenging because the inverse problem is ill-posed. Prior information can be used to improve image quality. Inspired by the kernel methods in machine learning, this paper proposes a kernel based method that models PET image intensity in each pixel as a function of a set of features obtained from prior information. The kernel-based image model is incorporated into the forward model of PET projection data and the coefficients can be readily estimated by the maximum likelihood (ML) or penalized likelihood image reconstruction. A kernelized expectation-maximization (EM) algorithm is presented to obtain the ML estimate. Computer simulations show that the proposed approach can achieve better bias versus variance trade-off and higher contrast recovery for dynamic PET image reconstruction than the conventional maximum likelihood method with and without post-reconstruction denoising. Compared with other regularization-based methods, the kernel method is easier to implement and provides better image quality for low-count data. Application of the proposed kernel method to a 4D dynamic PET patient dataset showed promising results. PMID:25095249

  12. Bullet trajectory reconstruction - Methods, accuracy and precision.

    PubMed

    Mattijssen, Erwin J A T; Kerkhoff, Wim

    2016-05-01

    Based on the spatial relation between a primary and secondary bullet defect or on the shape and dimensions of the primary bullet defect, a bullet's trajectory prior to impact can be estimated for a shooting scene reconstruction. The accuracy and precision of the estimated trajectories will vary depending on variables such as, the applied method of reconstruction, the (true) angle of incidence, the properties of the target material and the properties of the bullet upon impact. This study focused on the accuracy and precision of estimated bullet trajectories when different variants of the probing method, ellipse method, and lead-in method are applied on bullet defects resulting from shots at various angles of incidence on drywall, MDF and sheet metal. The results show that in most situations the best performance (accuracy and precision) is seen when the probing method is applied. Only for the lowest angles of incidence the performance was better when either the ellipse or lead-in method was applied. The data provided in this paper can be used to select the appropriate method(s) for reconstruction and to correct for systematic errors (accuracy) and to provide a value of the precision, by means of a confidence interval of the specific measurement. PMID:27044032

  13. Magnetic flux reconstruction methods for shaped tokamaks

    SciTech Connect

    Tsui, Chi-Wa

    1993-12-01

    The use of a variational method permits the Grad-Shafranov (GS) equation to be solved by reducing the problem of solving the 2D non-linear partial differential equation to the problem of minimizing a function of several variables. This high speed algorithm approximately solves the GS equation given a parameterization of the plasma boundary and the current profile (p` and FF` functions). The author treats the current profile parameters as unknowns. The goal is to reconstruct the internal magnetic flux surfaces of a tokamak plasma and the toroidal current density profile from the external magnetic measurements. This is a classic problem of inverse equilibrium determination. The current profile parameters can be evaluated by several different matching procedures. Matching of magnetic flux and field at the probe locations using the Biot-Savart law and magnetic Green`s function provides a robust method of magnetic reconstruction. The matching of poloidal magnetic field on the plasma surface provides a unique method of identifying the plasma current profile. However, the power of this method is greatly compromised by the experimental errors of the magnetic signals. The Casing Principle provides a very fast way to evaluate the plasma contribution to the magnetic signals. It has the potential of being a fast matching method. The performance of this method is hindered by the accuracy of the poloidal magnetic field computed from the equilibrium solver. A flux reconstruction package has been implemented which integrates a vacuum field solver using a filament model for the plasma, a multi-layer perception neural network as an interface, and the volume integration of plasma current density using Green`s functions as a matching method for the current profile parameters. The flux reconstruction package is applied to compare with the ASEQ and EFIT data. The results are promising.

  14. Arterial complications, venous thromboembolism and deep venous thrombosis prophylaxis after anterior cruciate ligament reconstruction: A systematic review

    PubMed Central

    Janssen, Rob Paulus Augustinus; Reijman, Max; Janssen, Daan Martijn; van Mourik, Jan Bernardus Antonius

    2016-01-01

    AIM To summarize the current knowledge on vascular complications and deep venous thrombosis (DVT) prophylaxis after anterior cruciate ligament (ACL) reconstruction. METHODS A systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement. MEDLINE, EMBASE, Cochrane, Web of Science, CINAHL, PubMed publisher, and Google scholar medical literature databases were searched up to November 10, 2015. Any arthroscopic surgical method of primary or revision intra-articular ACL reconstruction of all graft types in humans was included. A risk of bias assessment was determined. RESULTS Fourty-seven studies were included in the review. Pseudaneurysms were the most frequently reported arterial complication after ACL reconstruction, irrespective of graft type or method of graft fixation with an incidence of 0.3%. The time to diagnosis of arterial complications after ACL reconstruction varied from days to mostly weeks but even years. After ACL reconstruction without thromboprophylaxis, the incidence of DVT was 9.7%, of which 2.1% was symptomatic. The incidence of pulmonary embolism was 0.1%. Tourniquet time > 2 h was related to venous thromboembolism. Thromboprophylaxis is indicated in patients with risk factors for venous thromboembolism. CONCLUSION After ACL reconstruction, the incidence of arterial complications, symptomatic DVT and pulmonary embolism was 0.3%, 2.1% and 0.1% respectively. Arterial complications may occur with all types of arthroscopic ACL reconstruction, methods of graft fixation as well as any type of graft. Patients considered to be at moderate or high risk of venous thromboembolism should routinely receive thromboprophylaxis after ACL reconstruction.

  15. Arterial complications, venous thromboembolism and deep venous thrombosis prophylaxis after anterior cruciate ligament reconstruction: A systematic review

    PubMed Central

    Janssen, Rob Paulus Augustinus; Reijman, Max; Janssen, Daan Martijn; van Mourik, Jan Bernardus Antonius

    2016-01-01

    AIM To summarize the current knowledge on vascular complications and deep venous thrombosis (DVT) prophylaxis after anterior cruciate ligament (ACL) reconstruction. METHODS A systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement. MEDLINE, EMBASE, Cochrane, Web of Science, CINAHL, PubMed publisher, and Google scholar medical literature databases were searched up to November 10, 2015. Any arthroscopic surgical method of primary or revision intra-articular ACL reconstruction of all graft types in humans was included. A risk of bias assessment was determined. RESULTS Fourty-seven studies were included in the review. Pseudaneurysms were the most frequently reported arterial complication after ACL reconstruction, irrespective of graft type or method of graft fixation with an incidence of 0.3%. The time to diagnosis of arterial complications after ACL reconstruction varied from days to mostly weeks but even years. After ACL reconstruction without thromboprophylaxis, the incidence of DVT was 9.7%, of which 2.1% was symptomatic. The incidence of pulmonary embolism was 0.1%. Tourniquet time > 2 h was related to venous thromboembolism. Thromboprophylaxis is indicated in patients with risk factors for venous thromboembolism. CONCLUSION After ACL reconstruction, the incidence of arterial complications, symptomatic DVT and pulmonary embolism was 0.3%, 2.1% and 0.1% respectively. Arterial complications may occur with all types of arthroscopic ACL reconstruction, methods of graft fixation as well as any type of graft. Patients considered to be at moderate or high risk of venous thromboembolism should routinely receive thromboprophylaxis after ACL reconstruction. PMID:27672574

  16. Bridge-Enhanced ACL Repair: A Review of the Science and the Pathway through FDA Investigational Device Approval

    PubMed Central

    Proffen, Benedikt L.; Perrone, Gabriel S.; Roberts, Gordon; Murray, Martha M.

    2016-01-01

    Injuries to the anterior cruciate ligament (ACL) are currently treated with replacement of the torn ligament with a graft of tendon harvested from elsewhere in the knee. This procedure, called "ACL reconstruction," is excellent for restoring gross stability to the knee; however, there are relatively high graft failure rates in adolescent patients,4, 12, 60 and the ACL reconstruction procedure does not prevent the premature osteoarthritis seen in patients after an ACL injury.1, 46, 52 Thus, new solutions are needed for ACL injuries. Researchers have been investigating the use of scaffolds, growth factors and cells to supplement a suture repair of the ACL (bio-enhanced repair). In this paper, we will review the varied approaches, which have been investigated for stimulating ACL healing and repair in preclinical models and how one of these technologies was able to move from promising preclinical results to FDA acceptance of an Investigational Device Exemption (IDE) application for a first-in-human study. PMID:25631206

  17. Pragmatic reconstruction methods in atom probe tomography.

    PubMed

    Vurpillot, F; Gruber, M; Da Costa, G; Martin, I; Renaud, L; Bostel, A

    2011-07-01

    Data collected in atom probe tomography have to be carefully analysed in order to give reliable composition data accurately and precisely positioned in the probed volume. Indeed, the large analysed surfaces of recent instruments require reconstruction methods taking into account not only the tip geometry but also accurate knowledge of geometrical projection parameters. This is particularly crucial in the analysis of multilayers materials or planar interfaces. The current work presents a simulation model that enables extraction of the two main projection features as a function of the tip and atom probe instrumentation geometries. Conversely to standard assumptions, the image compression factor and the field factor vary significantly during the analysis. An improved reconstruction method taking into account the intrinsic shape of a sample containing planar features is proposed to overcome this shortcoming.

  18. Autograft versus allograft in anterior cruciate ligament reconstruction

    PubMed Central

    Kan, Shun-Li; Yuan, Zhi-Fang; Ning, Guang-Zhi; Yang, Bo; Li, Hai-Liang; Sun, Jing-Cheng; Feng, Shi-Qing

    2016-01-01

    Abstract Background: Anterior cruciate ligament (ACL) reconstruction is considered as the standard surgical procedure for the treatment of ACL tear. However, there is a crucial controversy in terms of whether to use autograft or allograft in ACL reconstruction. The purpose of this meta-analysis is to compare autograft with allograft for patients undergoing ACL reconstruction. Methods: PubMed, EMBASE, and the Cochrane Library were searched for randomized controlled trials that compared autograft with allograft in ACL reconstruction up to January 31, 2016. The relative risk or mean difference with 95% confidence interval was calculated using either a fixed- or random-effects model. The risk of bias for individual studies according to the Cochrane Handbook. The trial sequential analysis was used to test the robustness of our findings and get more conservative estimates. Results: Thirteen trials were included, involving 1636 participants. The results of this meta-analysis indicated that autograft brought about lower clinical failure, better overall International Knee Documentation Committee (IKDC) level, better pivot-shift test, better Lachman test, greater Tegner score, and better instrumented laxity test (P < 0.05) than allograft. Autograft was not statistically different from allograft in Lysholm score, subjective IKDC score, and Daniel 1-leg hop test (P > 0.05). Subgroup analyses demonstrated that autograft was superior to irradiated allograft for patients undergoing ACL reconstruction in clinical failure, Lysholm score, pivot-shift test, Lachman test, Tegner score, instrumented laxity test, and subjective IKDC score (P < 0.05). Moreover, there were no significant differences between autograft and nonirradiated allograft. Conclusions: Autograft is superior to irradiated allograft for patients undergoing ACL reconstruction concerning knee function and laxity, but there are no significant differences between autograft and nonirradiated allograft. However

  19. THE EFFECT OF CONSERVATIVELY TREATED ACL INJURY ON KNEE JOINT POSITION Sense

    PubMed Central

    Herrington, Lee

    2016-01-01

    ABSTRACT Background Proprioception is critical for effective movement patterns. However, methods of proprioceptive measurement in previous research have been inconsistent and lacking in reliability statistics making it applications to clinical practice difficult. Researchers have suggested that damage to the anterior cruciate ligament (ACL) can alter proprioceptive ability due to a loss of functioning mechanoreceptors. The majority of patients opt for reconstructive surgery following this injury. However, some patients chose conservative rehabilitation options rather than surgical intervention. Purpose The purpose of this study was to determine the effect of ACL deficiency on knee joint position sense following conservative, non-operative treatment and return to physical activity. A secondary purpose was to report the reliability and measurement error of the technique used to measure joint position sense, (JPS) and comment on the clinical utility of this measurement. Study Design Observational study design using a cross-section of ACL deficient patients and matched uninjured controls. Methods Twenty active conservatively treated ACL deficient patients who had returned to physical activity and twenty active matched controls were included in the study. Knee joint position sense was measured using a seated passive-active reproductive angle technique. The average absolute angle of error score, between 10 °-30 ° of knee flexion was determined. This error score was derived from the difference between the target and repositioning angle. Results The ACL deficient patients had a greater error score (7.9 °±3.6) and hence poorer static proprioception ability that both the contra-lateral leg (2.0 °±1.6; p = 0.0001) and the control group (2.6 °±0.9; p = 0.0001). The standard error of the mean (SEM) of this JPS technique was 0.5 ° and 0.2 ° and the minimum detectable change (MDC) was 1.3 ° and 0.4 ° on asymptomatic and symptomatic subjects

  20. Osteonecrosis of the Knee After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Lansdown, Drew A.; Shaw, Jeremy; Allen, Christina R.; Ma, C. Benjamin

    2015-01-01

    Background: Anterior cruciate ligament (ACL) reconstruction is performed commonly, with a low risk of complication. Osteonecrosis of the knee is a potentially devastating condition and has been observed both spontaneously and after meniscectomy, although osteonecrosis has not been described as a complication after ACL reconstruction. Purpose: To describe the development of osteonecrosis of the knee in 5 patients after arthroscopic ACL reconstruction. Study Design: Case series; Level of evidence, 4. Methods: This study involved 5 patients (mean age, 33.2 years) who developed osteonecrosis of the knee after ACL reconstruction. A retrospective chart review was performed to identify clinical characteristics and surgical factors present in each of the 5 cases. Results: In 4 cases, the pathologic changes were present in both the medial and lateral femoral condyles, with isolated lateral condyle changes in the other case. The mean time to diagnosis was 11.6 months. These patients underwent an average of 1.8 additional surgical procedures after the diagnosis of osteonecrosis. Conclusion: Osteonecrosis of the knee is a rare outcome after ACL reconstruction. We are unable to identify clear risk factors for the development of this complication, although we hope the presentation of these cases will help promote the identification of other cases in future studies. PMID:26665035

  1. KOOS Pain as a Marker for Significant Knee Pain Two and Six Years after Primary ACL Reconstruction: A Multicenter Orthopaedic Outcomes Network (MOON) Prospective Longitudinal Cohort Study

    PubMed Central

    Wasserstein, D; Huston, LJ; Nwosu, S; Spindler, KP

    2015-01-01

    Objective The prevalence of radiographic osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR) approaches 50%, yet the prevalence of significant knee pain is unknown. We applied three different models of Knee injury and Osteoarthritis Outcome Score (KOOS) thresholds for significant knee pain to an ACLR cohort to identify prevalence and risk factors. Design Multicenter Orthopaedic Outcomes Network (MOON) prospective cohort patients with a unilateral primary ACLR and normal contralateral knee were assessed at 2 and 6 years. Independent variables included patient demographics, validated Patient Reported Outcomes (PRO; Marx activity score, KOOS), and surgical characteristics. Models included: (1) KOOS criteria for a painful knee = quality of life subscale <87.5 and ≥2 of: KOOSpain <86.1, KOOSsymptoms <85.7, KOOSADL <86.8, or KOOSsports/rec <85.0; (2) KOOSpain subscale score ≤72 (≥2 standard deviations below population mean); (3) 10-point KOOSpain drop from 2 to 6 years. Proportional odds models (alpha≤0.05) were used. Results 1,761 patients of median age 23 years, median BMI 24.8 kg/m2 and 56% male met inclusion, with 87% (1530/1761) and 86% (1506/1761) follow-up at 2 and 6 years, respectively. At 6 years, n=592 (39%), n=131 (9%) and n=169 (12%) met criteria for models #1 through #3, respectively. The most consistent and strongest independent risk factor at both time-points was subsequent ipsilateral knee surgery. Low 2-year Marx activity score increased the odds of a painful knee at 6 years. Conclusions Significant knee pain is prevalent after ACLR; with those who undergo subsequent ipsilateral surgery at greatest risk. The relationship between pain and structural OA warrants further study. PMID:26072385

  2. Inverse polynomial reconstruction method in DCT domain

    NASA Astrophysics Data System (ADS)

    Dadkhahi, Hamid; Gotchev, Atanas; Egiazarian, Karen

    2012-12-01

    The discrete cosine transform (DCT) offers superior energy compaction properties for a large class of functions and has been employed as a standard tool in many signal and image processing applications. However, it suffers from spurious behavior in the vicinity of edge discontinuities in piecewise smooth signals. To leverage the sparse representation provided by the DCT, in this article, we derive a framework for the inverse polynomial reconstruction in the DCT expansion. It yields the expansion of a piecewise smooth signal in terms of polynomial coefficients, obtained from the DCT representation of the same signal. Taking advantage of this framework, we show that it is feasible to recover piecewise smooth signals from a relatively small number of DCT coefficients with high accuracy. Furthermore, automatic methods based on minimum description length principle and cross-validation are devised to select the polynomial orders, as a requirement of the inverse polynomial reconstruction method in practical applications. The developed framework can considerably enhance the performance of the DCT in sparse representation of piecewise smooth signals. Numerical results show that denoising and image approximation algorithms based on the proposed framework indicate significant improvements over wavelet counterparts for this class of signals.

  3. Combined anterolateral ligament and anatomic anterior cruciate ligament reconstruction of the knee.

    PubMed

    Smith, James O; Yasen, Sam K; Lord, Breck; Wilson, Adrian J

    2015-11-01

    Although anatomic anterior cruciate ligament (ACL) reconstruction is established for the surgical treatment of anterolateral knee instability, there remains a significant cohort of patients who continue to experience post-operative instability. Recent advances in our understanding of the anatomic, biomechanical and radiological characteristics of the native anterolateral ligament (ALL) of the knee have led to a resurgent interest in reconstruction of this structure as part of the management of knee instability. This technical note describes our readily reproducible combined minimally invasive technique to reconstruct both the ACL and ALL anatomically using autologous semitendinosus and gracilis grafts. This method of ALL reconstruction can be easily integrated with all-inside ACL reconstruction, requiring minimal additional operative time, equipment and expertise. Level of evidence V.

  4. Association Between Previous Meniscal Surgery and the Incidence of Chondral Lesions at Revision Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Brophy, Robert H.; Wright, Rick W.; David, Tal S.; McCormack, Robert G.; Sekiya, Jon K.; Svoboda, Steven J.; Huston, Laura J.; Haas, Amanda K.; Steger-May, Karen

    2013-01-01

    Background Knees undergoing revision anterior cruciate ligament (ACL) reconstruction typically have more intra-articular injuries than do knees undergoing primary reconstruction. Hypothesis Previous partial meniscectomy (PM) is associated with a higher rate of chondral lesions at revision ACL reconstruction, whereas previous meniscal repair (MR) is not associated with a higher rate of chondral lesions at revision ACL reconstruction, compared with knees undergoing revision ACL with no previous meniscal surgery. Study design Cohort study (Prevalence); Level of evidence, 2. Methods Data from a multicenter cohort was reviewed to determine the history of prior meniscal surgery (PM/MR) and the presence of grade II/III/IV chondral lesions at revision ACL reconstruction. The association between previous meniscal surgery and the incidence of chondral lesions was examined. Patient age was included as a covariate to determine if surgery type contributes predictive information independent of patient age. Results The cohort included 725 ACL revision surgeries. Chondrosis was associated with patient age (P < .0001) and previous meniscal surgery (P < .0001). After adjusting for patient age, knees with previous PM were more likely to have chondrosis than knees with previous MR (P = .003) or no previous meniscal surgery (P < .0001). There was no difference between knees without previous meniscal surgery and knees with previous MR (P = .7). Previous partial meniscectomy was associated with a higher rate of chondrosis in the same compartment compared with knees without previous meniscal surgery (P < .0001) and knees with previous MR (P ≤ .03). Conclusion The status of articular cartilage at the time of revision ACL reconstruction relates to previous meniscal surgery independent of the effect of patient age. Previous partial meniscectomy is associated with a higher incidence of articular cartilage lesions, whereas previous meniscal repair is not. Although this association may

  5. Method of reconstructing a moving pulse

    NASA Astrophysics Data System (ADS)

    Howard, S. J.; Horton, R. D.; Hwang, D. Q.; Evans, R. W.; Brockington, S. J.; Johnson, J.

    2007-11-01

    We present a method of analyzing a set of N time signals fi(t) that consist of local measurements of the same physical observable taken at N sequential locations Zi along the length of an experimental device. The result is an algorithm for reconstructing an approximation F(z,t) of the field f(z,t) in the inaccessible regions between the points of measurement. We also explore the conditions needed for this approximation to hold, and test the algorithm under a variety of conditions. We apply this method to analyze the magnetic field measurements taken on the Compact Toroid Injection eXperiment (CTIX) plasma accelerator; providing a direct means of visualizing experimental data, quantifying global properties, and benchmarking simulation.

  6. Effect of Timing of Surgery in Partially Injured ACLs.

    PubMed

    Li, Bin; Bai, Lunhao; Fu, Yonghui; Wang, Guangbin; He, Ming; Wang, Jiashi

    2012-05-01

    The purpose of this study was to explore the optimal timing for surgical intervention of partially injured anterior cruciate ligaments (ACL). Thirty-eight patients were divided into early (n=17) or delayed (n=21) surgery groups based on the interval between injury and surgery. Minimum follow-up was 2 years. The outcome measures used were the International Knee Documentation Committee score, Lysholm knee score, Tegner activity rating, range of motion, and arthrometer measurements. The findings of this study indicate that early surgical reconstruction of partially ruptured ACLs did not result in arthrofibrosis but may prevent secondary loosening of the intact bundles and further meniscal and chondral injury.

  7. Graft impingement in anterior cruciate ligament reconstruction.

    PubMed

    Iriuchishima, Takanori; Shirakura, Kenji; Fu, Freddie H

    2013-03-01

    Anterior cruciate ligament (ACL) graft impingement is one of the most troubling complications in ACL reconstruction. In the previous strategy of isometric "non-anatomical" ACL reconstruction, posterior tibial tunnel placement and notchplasty were recommended to avoid graft impingement. Recently, the strategy of ACL reconstruction is shifting towards "anatomical" reconstruction. In anatomical ACL reconstruction, the potential risk of graft impingement is higher than in non-anatomical reconstruction because the tibial tunnel is placed at a more anterior portion on the tibia. However, there have been few studies reporting on graft impingement in anatomical ACL reconstruction. This study will provide a review of graft impingement status in both non-anatomical and the more recent anatomical ACL reconstruction techniques. In conclusion, with the accurate creation of bone tunnels within ACL native footprint, the graft impingement might not happen in anatomical ACL reconstruction. For the clinical relevance, to prevent graft impingement, surgeons should pay attention of creating correct anatomical tunnels when they perform ACL reconstruction. Level of evidence IV.

  8. Anterior Cruciate Ligament (ACL) Injuries

    MedlinePlus

    ... get ACL injuries usually play contact sports (like football) or sports that feature swift, abrupt movements such ... the things you love — like running or playing football, field hockey, or softball — can be frustrating. Recovering ...

  9. Athletic Performance at the National Basketball Association Combine After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Mehran, Nima; Williams, Phillip N.; Keller, Robert A.; Khalil, Lafi S.; Lombardo, Stephen J.; Kharrazi, F. Daniel

    2016-01-01

    Background: Anterior cruciate ligament (ACL) injuries are significant injuries in elite-level basketball players. In-game statistical performance after ACL reconstruction has been demonstrated; however, few studies have reviewed functional performance in National Basketball Association (NBA)–caliber athletes after ACL reconstruction. Purpose: To compare NBA Combine performance of athletes after ACL reconstruction with an age-, size-, and position-matched control group of players with no previous reported knee injury requiring surgery. We hypothesized that there is no difference between the 2 groups in functional performance. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 1092 NBA-caliber players who participated in the NBA Combine between 2000 and 2015 were reviewed. Twenty-one athletes were identified as having primary ACL reconstruction prior to participation in the combine. This study group was compared with an age-, size-, and position-matched control group in objective functional performance testing, including the shuttle run test, lane agility test, three-quarter court sprint, vertical jump (no step), and maximum vertical jump (running start). Results: With regard to quickness and agility, both ACL-reconstructed athletes and controls scored an average of 11.5 seconds in the lane agility test and 3.1 seconds in the shuttle run test (P = .745 and .346, respectively). Speed and acceleration was measured by the three-quarter court sprint, in which both the study group and the control group averaged 3.3 seconds (P = .516). In the maximum vertical jump, which demonstrates an athlete’s jumping ability with a running start, the ACL reconstruction group had an average height of 33.6 inches while the controls averaged 33.9 inches (P = .548). In the standing vertical jump, the ACL reconstruction group averaged 28.2 inches while the control group averaged 29.2 inches (P = .067). Conclusion: In athletes who are able to return to sport

  10. Tibial Fixation Properties of a Continuous-Loop ACL Hamstring Graft Construct with Suspensory Fixation in Porcine Bone.

    PubMed

    Smith, Patrick A; DeBerardino, Thomas M

    2015-12-01

    The aim of this article is to compare tibial fixation strength of suspensory fixation for a quadrupled semitendinosus continuous loop all-inside anterior cruciate ligament (ACL) construct versus a doubled semitendinosus and gracilis graft fixated with an interference screw. Biomechanical testing was conducted using human hamstring allografts and porcine tibias. Constructs were cycled from 50 to 250 N for 500 cycles followed by a pull to failure. The average load to failure of tibial suspensory fixation of the all-inside continuous loop construct (1,012 N) was statistically different compared with the tibial interference screw group (612 N) (p < 0.001). The cyclic displacement of the continuous loop construct (2.5 mm) was not statistically different from the interference screw construct (1.9 mm). For both the groups, approximately half the overall cyclic displacement occurred with the first cycle. Tibial side suspensory fixation of a novel all-inside continuous loop hamstring graft provided suitable strength for tibial fixation for ACL reconstruction. The continuous loop construct had a significantly higher load to failure compared with the use of an interference screw, and cyclic loading was comparable. Use of hamstring soft tissue grafts is very common for ACL reconstruction. An all-inside ACL reconstruction is based on a continuous loop construct utilizing a single semitendinosus graft that is quadrupled employing suspensory fixation on both the femoral and tibial side. Suspensory fixation on the femoral side been previously reported, but this is the first report of strength of this method of suspensory fixation on the tibia. PMID:25347056

  11. Auricular reconstruction for microtia: A review of available methods

    PubMed Central

    Baluch, Narges; Nagata, Satoru; Park, Chul; Wilkes, Gordon H; Reinisch, John; Kasrai, Leila; Fisher, David

    2014-01-01

    Several surgical techniques have been described for auricular reconstruction. Autologous reconstruction using costal cartilage is the most widely accepted technique of microtia repair. However, other techniques have certain indications and should be discussed with patients and families when planning for an auricular reconstruction. In the present review, the authors discuss the main surgical techniques for auricular reconstruction including autologous costal cartilage graft, Medpor (Stryker, USA) implant and prosthetic reconstruction. To further elaborate on the advantages and disadvantages of each technique, the authors invited leaders in this field, Dr Nagata, Dr Park, Dr Reinisch and Dr Wilkes, to comment on their own technique and provide examples of their methods. PMID:25152646

  12. A Comparative Study of Different Reconstruction Schemes for a Reconstructed Discontinuous Galerkin Method on Arbitrary Grids

    SciTech Connect

    Hong Luo; Hanping Xiao; Robert Nourgaliev; Chunpei Cai

    2011-06-01

    A comparative study of different reconstruction schemes for a reconstruction-based discontinuous Galerkin, termed RDG(P1P2) method is performed for compressible flow problems on arbitrary grids. The RDG method is designed to enhance the accuracy of the discontinuous Galerkin method by increasing the order of the underlying polynomial solution via a reconstruction scheme commonly used in the finite volume method. Both Green-Gauss and least-squares reconstruction methods and a least-squares recovery method are implemented to obtain a quadratic polynomial representation of the underlying discontinuous Galerkin linear polynomial solution on each cell. These three reconstruction/recovery methods are compared for a variety of compressible flow problems on arbitrary meshes to access their accuracy and robustness. The numerical results demonstrate that all three reconstruction methods can significantly improve the accuracy of the underlying second-order DG method, although the least-squares reconstruction method provides the best performance in terms of both accuracy and robustness.

  13. A new target reconstruction method considering atmospheric refraction

    NASA Astrophysics Data System (ADS)

    Zuo, Zhengrong; Yu, Lijuan

    2015-12-01

    In this paper, a new target reconstruction method considering the atmospheric refraction is presented to improve 3D reconstruction accuracy in long rang surveillance system. The basic idea of the method is that the atmosphere between the camera and the target is partitioned into several thin layers radially in which the density is regarded as uniform; Then the reverse tracking of the light propagation path from sensor to target was carried by applying Snell's law at the interface between layers; and finally the average of the tracked target's positions from different cameras is regarded as the reconstructed position. The reconstruction experiments were carried, and the experiment results showed that the new method have much better reconstruction accuracy than the traditional stereoscopic reconstruction method.

  14. Magnetic Field Configuration Models and Reconstruction Methods: a comparative study

    NASA Astrophysics Data System (ADS)

    Al-haddad, Nada; Möstl, Christian; Roussev, Ilia; Nieves-Chinchilla, Teresa; Poedts, Stefaan; Hidalgo, Miguel Angel; Marubashi, Katsuhide; Savani, Neel

    2012-07-01

    This study aims to provide a reference to different magnetic field models and reconstruction methods. In order to understand the dissimilarities of those models and codes, we analyze 59 events from the CDAW list, using four different magnetic field models and reconstruction techniques; force- free reconstruction (Lepping et al.(1990); Lynch et al.(2003)), magnetostatic reconstruction, referred as Grad-Shafranov (Hu & Sonnerup(2001); Mostl et al.(2009)), cylinder reconstruction (Marubashi & Lepping(2007)), elliptical, non-force free (Hidalgo et al.(2002)). The resulted parameters of the reconstructions, for the 59 events are compared, statistically, as well as in more details for some cases. The differences between the reconstruction codes are discussed, and suggestions are provided as how to enhance them. Finally we look at 2 unique cases under the microscope, to provide a comprehensive idea of the different aspects of how the fitting codes work.

  15. A Comparison between Clinical Results of Selective Bundle and Double Bundle Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Yoo, Yon-Sik; Song, Si Young; Yang, Cheol Jung; Ha, Jong Mun; Kim, Yoon Sang

    2016-01-01

    Purpose The purpose of this study was to compare the clinical outcomes of arthroscopic anatomical double bundle (DB) anterior cruciate ligament (ACL) reconstruction with either selective anteromedial (AM) or posterolateral (PL) bundle reconstruction while preserving a relatively healthy ACL bundle. Materials and Methods The authors evaluated 98 patients with a mean follow-up of 30.8±4.0 months who had undergone DB or selective bundle ACL reconstructions. Of these, 34 cases underwent DB ACL reconstruction (group A), 34 underwent selective AM bundle reconstruction (group B), and 30 underwent selective PL bundle reconstructions (group C). These groups were compared with respect to Lysholm and International Knee Documentation Committee (IKDC) score, side-to-side differences of anterior laxity measured by KT-2000 arthrometer at 30 lbs, and stress radiography and Lachman and pivot shift test results. Pre- and post-operative data were objectively evaluated using a statistical approach. Results The preoperative anterior instability measured by manual stress radiography at 90° of knee flexion in group A was significantly greater than that in groups B and C (all p<0.001). At last follow-up, mean side-to-side instrumented laxities measured by the KT-2000 and manual stress radiography were significantly improved from preoperative data in all groups (all p<0.001). There were no significant differences between the three groups in anterior instability measured by KT-2000 arthrometer, pivot shift, or functional scores. Conclusion Selective bundle reconstruction in partial ACL tears offers comparable clinical results to DB reconstruction in complete ACL tears. PMID:27401652

  16. Two-Stage Revision Anterior Cruciate Ligament Reconstruction.

    PubMed

    Erickson, Brandon J; Cvetanovich, Gregory; Waliullah, Khalid; Khair, Michael; Smith, Patrick; Bach, Bernard; Sherman, Seth

    2016-05-01

    The number of primary anterior cruciate ligament (ACL) tears is rapidly increasing. In patients who wish to return to their preoperative level of function, specifically as it pertains to participation in sports, the gold standard of treatment following an ACL tear remains an anterior cruciate ligament (ACL) reconstruction. Despite a majority of good/excellent results following primary ACL reconstruction, there is a growing subset of patients with persistent or recurrent functional instability who require revision ACL reconstruction. Preoperative planning for revision ACL reconstruction requires a careful understanding of the root cause of ACL failure, including possible technical causes of primary ACL failure and the presence of combined knee pathology that was not addressed at the index ACL reconstruction. The decision to perform 2-stage revision ACL reconstruction is multifactorial and is reached by technical considerations that may make a 1-stage revision less optimal, including tunnel widening, arthrofibrosis, active infection, and others. Concomitant knee pathology such as meniscal deficiency, malalignment (including an increase in posterior tibial slope), chondral lesions, and other ligamentous laxity may also require a staged approach to treatment. This evidence-based review covers the indications for 2-stage revision ACL reconstruction, surgical techniques, evidence for and technique of bone grafting prior ACL tunnels, and outcomes of 2-stage revision stratified by initial cause of ACL reconstruction failure. With proper preoperative planning and an understanding of the cause of failure following the primary ACL reconstruction, revision ACL reconstruction can offer excellent outcomes in the motivated patient. [Orthopedics. 2016; 39(3):e456-e464.]. PMID:27045480

  17. Individualized anatomic anterior cruciate ligament reconstruction.

    PubMed

    van Eck, Carola F; Widhalm, Harrald; Murawski, Christopher; Fu, Freddie H

    2015-02-01

    Anterior cruciate ligament (ACL) injuries are often seen in young participants in sports such as soccer, football, and basketball. Treatment options include conservative management as well as surgical intervention, with the goal of enabling the patient to return to cutting and pivoting sports and activities. Individualized anatomic ACL reconstruction is a surgical technique that tailors the procedure to the individual patient using preoperative measurements on plain radiographs and magnetic resonance imaging and intraoperative measurement to map the patients' native ACL anatomy in order to replicate it as closely as possible. Anatomic ACL reconstruction, therefore, is defined as reconstruction of the ACL to its native dimensions, collagen orientation, and insertion site. The surgical reconstruction is followed by a specific rehabilitation protocol that is designed to enable the patient to regain muscle strength and proprioception while facilitating healing of the reconstructed ACL prior to the patient's returning to sports activities.

  18. Interior reconstruction method based on rotation-translation scanning model.

    PubMed

    Wang, Xianchao; Tang, Ziyue; Yan, Bin; Li, Lei; Bao, Shanglian

    2014-01-01

    In various applications of computed tomography (CT), it is common that the reconstructed object is over the field of view (FOV) or we may intend to sue a FOV which only covers the region of interest (ROI) for the sake of reducing radiation dose. These kinds of imaging situations often lead to interior reconstruction problems which are difficult cases in the reconstruction field of CT, due to the truncated projection data at every view angle. In this paper, an interior reconstruction method is developed based on a rotation-translation (RT) scanning model. The method is implemented by first scanning the reconstructed region, and then scanning a small region outside the support of the reconstructed object after translating the rotation centre. The differentiated backprojection (DBP) images of the reconstruction region and the small region outside the object can be respectively obtained from the two-time scanning data without data rebinning process. At last, the projection onto convex sets (POCS) algorithm is applied to reconstruct the interior region. Numerical simulations are conducted to validate the proposed reconstruction method.

  19. High resolution x-ray CMT: Reconstruction methods

    SciTech Connect

    Brown, J.K.

    1997-02-01

    This paper qualitatively discusses the primary characteristics of methods for reconstructing tomographic images from a set of projections. These reconstruction methods can be categorized as either {open_quotes}analytic{close_quotes} or {open_quotes}iterative{close_quotes} techniques. Analytic algorithms are derived from the formal inversion of equations describing the imaging process, while iterative algorithms incorporate a model of the imaging process and provide a mechanism to iteratively improve image estimates. Analytic reconstruction algorithms are typically computationally more efficient than iterative methods; however, analytic algorithms are available for a relatively limited set of imaging geometries and situations. Thus, the framework of iterative reconstruction methods is better suited for high accuracy, tomographic reconstruction codes.

  20. Body Mass Index, Modulated by Lateral Posterior Tibial Slope, Predicts ACL Injury Risk

    PubMed Central

    Bojicic, Katherine M.; Beaulieu, Melanie L.; Krieger, Daniel Imaizumi; Ashton-Miller, James A.; Wojtys, Edward M.

    2016-01-01

    Objectives: Intervention strategies to prevent ACL injury rely on increasing knowledge of risk factors. While several modifiable and non-modifiable risk factors for ACL rupture have been identified, the interaction between them remains unknown. The aim of this study was to quantify the relationship between BMI and several knee geometries as potential risk factors for ACL injury. We hypothesized that an increased BMI in the presence of an increased posterior tibial slope or middle cartilage slope would increase risk of ACL injury. We also hypothesized that an increased BMI in the presence of a decreased posterior meniscal height or meniscal bone angle would result in an increased risk of ACL injury. Methods: Sagittal knee MRI files from 76 ACL-injured and 42 non-injured subjects were gathered from the institution’s archive. The PTS, MCS, PMH, and MBA were measured using the circle method and compared with BMI from the subject demographic. Data were analyzed using univariate and multivariate logistical regression. Figure 1 details measurements made for each knee geometry. Results: Univariate analysis of PTS showed increases in PTS significantly increase the odds of ACL tear (p = 0.043, OR =1.12). Univariate analysis of MCS showed increases of MCS significantly increase the odds of ACL tear (p = 0.037, OR = 1.12). Multivariate analysis of PTS and BMI centered around the mean (PTS*cBMI) showed increases of PTS in combination with increases in cBMI significantly increases the odds of ACL rupture (p value = .050, OR = 1.03). Table 1 shows predicted increases in ACL injury risk for combinations of increases in PTS and BMI. Conclusion: An increase in BMI will increase the risk of ACL tear when an increase in lateral posterior tibial slope is present. An increase in lateral posterior tibial slope or lateral middle cartilage slope increases the risk of an ACL tear.

  1. The ACL Message Passing Library

    SciTech Connect

    Painter, J.; McCormick, P.; Krogh, M.; Hansen, C.; Colin de Verdiere, G.

    1995-09-01

    This paper presents the ACL (Advanced Computing Lab) Message Passing Library. It is a high throughput, low latency communications library, based on Thinking Machines Corp.`s CMMD, upon which message passing applications can be built. The library has been implemented on the Cray T3D, Thinking Machines CM-5, SGI workstations, and on top of PVM.

  2. Application of mathematical modelling methods for acoustic images reconstruction

    NASA Astrophysics Data System (ADS)

    Bolotina, I.; Kazazaeva, A.; Kvasnikov, K.; Kazazaev, A.

    2016-04-01

    The article considers the reconstruction of images by Synthetic Aperture Focusing Technique (SAFT). The work compares additive and multiplicative methods for processing signals received from antenna array. We have proven that the multiplicative method gives a better resolution. The study includes the estimation of beam trajectories for antenna arrays using analytical and numerical methods. We have shown that the analytical estimation method allows decreasing the image reconstruction time in case of linear antenna array implementation.

  3. Multigrid hierarchical simulated annealing method for reconstructing heterogeneous media

    NASA Astrophysics Data System (ADS)

    Pant, Lalit M.; Mitra, Sushanta K.; Secanell, Marc

    2015-12-01

    A reconstruction methodology based on different-phase-neighbor (DPN) pixel swapping and multigrid hierarchical annealing is presented. The method performs reconstructions by starting at a coarse image and successively refining it. The DPN information is used at each refinement stage to freeze interior pixels of preformed structures. This preserves the large-scale structures in refined images and also reduces the number of pixels to be swapped, thereby resulting in a decrease in the necessary computational time to reach a solution. Compared to conventional single-grid simulated annealing, this method was found to reduce the required computation time to achieve a reconstruction by around a factor of 70-90, with the potential of even higher speedups for larger reconstructions. The method is able to perform medium sized (up to 3003 voxels) three-dimensional reconstructions with multiple correlation functions in 36-47 h.

  4. Tennis specific limitations in players with an ACL deficient knee

    PubMed Central

    Maquirriain, J; Megey, P J

    2006-01-01

    Background Complete rupture of the anterior cruciate ligament (ACL) causes significant alteration of knee joint kinematics. Untreated patients often develop joint instability, chronic articular degeneration, and knee dysfunction. Demands on the ACL produced by playing tennis have not been investigated. Objective To identify subjective sport‐specific limitations in tennis players with isolated unilateral ACL deficiency. Study design Prospective case–control study. Methods 16 players (mean (SD) age, 39.9 (2.3) years; 14 men) with a chronic unilateral ACL deficient knee and 16 healthy controls (38.25 (8.47) years; 14 men) were recruited. ACL deficiency was confirmed by clinical and magnetic resonance imaging. A Lysholm score was obtained in all patients, together with subjective evaluation of their current tennis performance compared with pre‐injury levels, applying a 0–100% visual scale. Both groups completed a questionnaire on tennis specific abilities. Results Lysholm scores were: 85.6 (10.3) points in the study group and 100 (0) points in the control group (p<0.001, t test for independent samples). Injured players evaluated their current tennis performance as 66.8 (15.2)% compared with 100% pre‐injury level (p<0.005, t test for dependent samples). Abilities affected in the ACL deficient group were landing after a smash stroke (p<0.001); stopping abruptly and changing (p<0.001); playing a three set singles match (p<0.05); and playing on a hard court surface (p<0.001, Kolmogorov‐Smirnov test). Conclusions There are specific limitations associated with complete isolated ACL rupture, including subjective tennis performance impairment, limitations landing after a smash, stopping and changing step direction, difficulties playing a three set singles match, and playing on hard court surfaces. PMID:16632578

  5. Infections in Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Stucken, Charlton; Garras, David N.; Shaner, Julie L.; Cohen, Steven B.

    2013-01-01

    Context: Anterior cruciate ligament (ACL) reconstruction is a safe, common, and effective method of restoring stability to the knee after injury, but evolving techniques of reconstruction carry inherent risk. Infection after ACL reconstruction, while rare, carries a high morbidity, potentially resulting in a poor clinical outcome. Evidence Acquisition: Data were obtained from previously published peer-reviewed literature through a search of the entire PubMed database (up to December 2012) as well as from textbook chapters. Results: Treatment with culture-specific antibiotics and debridement with graft retention is recommended as initial treatment, but with persistent infection, consideration should be given to graft removal. Graft type likely has no effect on infection rates. Conclusion: The early diagnosis of infection and appropriate treatment are necessary to avoid the complications of articular cartilage damage and arthrofibrosis. PMID:24427432

  6. PERI-INCISIONAL DYSESTHESIA FOLLOWING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING CENTRAL THIRD OF PATELLAR TENDON

    PubMed Central

    de Carvalho Júnior, Lúcio Honório; Machado, Soares Luiz Fernando; Gonçalves, Matheus Braga Jacques; Júnior, Paulo Randal Pires; Baumfeld, Daniel Soares; Pereira, Marcelo Lobo; Lessa, Rodrigo Rosa; Costa, Lincoln Paiva; Bisinoto, Henrique Barra

    2015-01-01

    Objective: To evaluate the prevalence and type of dysesthesia around the incision used to obtain the patellar tendon for anterior cruciate ligament (ACL) reconstruction surgery. Methods: Out of a population of 1368 ACL reconstructions using the central third of the patellar tendon, 102 patients (111 knees) were evaluated by means of telephone interview. Results: The mean follow-up was 52 months (ranging from 12 to 88 months). The patients' ages ranged from 16 to 58 years (mean: 34.7 years). There was some degree of peri-incisional dysesthesia in 66 knees (59.46%). In 40.54% of the knees, this condition was not found. In all the cases of dysesthesia, the type encountered was Highet's type II. Conclusion: Peri-incisional dysesthesia following ACL reconstruction using the central third of the patellar tendon is highly prevalent. It affected more than half of the cases in this series. PMID:27026983

  7. Comparison of Clinical Outcome of Autograft and Allograft Reconstruction for Anterior Cruciate Ligament Tears

    PubMed Central

    Jia, Yu-Hua; Sun, Peng-Fei

    2015-01-01

    Background: Hamstring (HS) autograft and bone-patellar tendon-bone allograft are the most common choice for reconstruction of anterior cruciate ligament (ACL). There was a little report about the clinical outcome and difference of arthroscopic ACL reconstruction using allograft and autograft. This study aimed to compare the clinical outcome of autograft and allograft reconstruction for ACL tears. Methods: A total of 106 patients who underwent surgery because of ACL tear were included in this study. The patients were randomly divided into two groups, including 53 patients in each group. The patients in group I underwent standard ACL reconstruction with HS tendon autografts, while others in group II underwent reconstruction with bone-patellar tendon-bone allograft. All the patients were followed up and analyzed; the mean follow-up was 81 months (range: 28–86 months). Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC), Lysholm scores, physical instability tests, and patient satisfaction questionnaires. The complication rates of both groups were compared. Tibial and femoral tunnel widening were assessed using lateral and anteroposterior radiographs. Results: At the end of follow-up, no significant differences were found between the groups in terms of IKDC, Lysholm scores, physical instability tests, patient satisfaction questionnaires, and incidences of arthrofibrosis. Tibial and femoral tunnel widening was less in the HS tendon autografts. This difference was more significant on the tibial side. Conclusions: In the repair of ACL tears, allograft reconstruction is as effective as the autograft reconstruction, but the allograft can lead to more tunnel widening evidently in the tibial tunnel, particularly. PMID:26612290

  8. Long Term Gait Deviations in Anterior Cruciate Ligament Reconstructed Females

    PubMed Central

    Noehren, Brian; Wilson, Hilary; Miller, Casey; Lattermann, Christian

    2015-01-01

    Purpose Little is known of the potential long term gait alterations that occur after an anterior cruciate ligament (ACL) reconstruction. In particular, variables such as impact loading which have been previously associated with joint deterioration have not been studied in walking and running after an ACL reconstruction. The purpose of this study was to define the alterations in impact forces, loading rates, and the accompanying sagittal plane kinematic and kinetic mechanics at the time of impact between the ACL reconstructed group and a healthy control group. Methods 40 females (20 ACL reconstruction, 20 controls) participated in the study. An instrumented gait analysis was performed on all subjects. Between group and limb comparisons were made for initial vertical impact force, loading rate, sagittal plane knee and hip angles as well as moments. Results During walking and running the ACL cohort had significantly greater initial vertical impact force (p=0.002 and p= 0.001), and loading rates (p=0.03 and p= 0.01), as well as a smaller knee extensor moment and hip angle during walking (p=0.000 and p=0.01). There was a trend towards a smaller knee moment and hip angle during running (p=0.08 and p=0.06) as well as a larger hip extensor moment during walking (p=0.06) in the ACL group. No differences were found for hip extensor moment during running, knee angles between groups during walking or running. Lastly, no between limb differences were found for any variable. Conclusion Gait deviations such as elevated impact loading and loading rates do not resolve long term after the individual has resumed previous activity levels and may contribute to the greater risk of early joint degeneration in this population. PMID:23568090

  9. An analytic reconstruction method for PET based on cubic splines

    NASA Astrophysics Data System (ADS)

    Kastis, George A.; Kyriakopoulou, Dimitra; Fokas, Athanasios S.

    2014-03-01

    PET imaging is an important nuclear medicine modality that measures in vivo distribution of imaging agents labeled with positron-emitting radionuclides. Image reconstruction is an essential component in tomographic medical imaging. In this study, we present the mathematical formulation and an improved numerical implementation of an analytic, 2D, reconstruction method called SRT, Spline Reconstruction Technique. This technique is based on the numerical evaluation of the Hilbert transform of the sinogram via an approximation in terms of 'custom made' cubic splines. It also imposes sinogram thresholding which restricts reconstruction only within object pixels. Furthermore, by utilizing certain symmetries it achieves a reconstruction time similar to that of FBP. We have implemented SRT in the software library called STIR and have evaluated this method using simulated PET data. We present reconstructed images from several phantoms. Sinograms have been generated at various Poison noise levels and 20 realizations of noise have been created at each level. In addition to visual comparisons of the reconstructed images, the contrast has been determined as a function of noise level. Further analysis includes the creation of line profiles when necessary, to determine resolution. Numerical simulations suggest that the SRT algorithm produces fast and accurate reconstructions at realistic noise levels. The contrast is over 95% in all phantoms examined and is independent of noise level.

  10. Anatomically-aided PET reconstruction using the kernel method

    NASA Astrophysics Data System (ADS)

    Hutchcroft, Will; Wang, Guobao; Chen, Kevin T.; Catana, Ciprian; Qi, Jinyi

    2016-09-01

    This paper extends the kernel method that was proposed previously for dynamic PET reconstruction, to incorporate anatomical side information into the PET reconstruction model. In contrast to existing methods that incorporate anatomical information using a penalized likelihood framework, the proposed method incorporates this information in the simpler maximum likelihood (ML) formulation and is amenable to ordered subsets. The new method also does not require any segmentation of the anatomical image to obtain edge information. We compare the kernel method with the Bowsher method for anatomically-aided PET image reconstruction through a simulated data set. Computer simulations demonstrate that the kernel method offers advantages over the Bowsher method in region of interest quantification. Additionally the kernel method is applied to a 3D patient data set. The kernel method results in reduced noise at a matched contrast level compared with the conventional ML expectation maximization algorithm.

  11. Precision of ACL tunnel placement using traditional and robotic techniques.

    PubMed

    Burkart, A; Debski, R E; McMahon, P J; Rudy, T; Fu, F H; Musahl, V; van Scyoc, A; Woo, S L

    2001-01-01

    The objective of this study was to examine the precision of ACL tunnel placement using: (1) CASPAR (orto MAQUET GmbH Co. KG)--an active robotic system, and (2) four orthopedic surgeons with various levels of experience (between 100 and 3,500 ACL reconstructions). The robotic system and each surgeon drilled tunnels for ACL reconstruction in 10 plastic knees (total n = 50) that included a reference cube in the medial aspect of the proximal tibia and distal femur. For the robotic system, the placement of each tunnel was planned preoperatively using custom software and CT data for each femur and tibia. The robotic system then drilled the tunnels in the femur and tibia based on the preoperative plan. For the surgeons, tunnel placement was accomplished using their preferred technique, which was based on the one-incision arthroscopic technique. The distribution of intra-articular points on the tibia was contained within a sphere of radius 2.0 mm (robot system), 2.1 mm (Fellow 1), 2.4 mm (Fellow 2), 3.4 mm (Experienced Surgeon 1), or 2.0 mm (Experienced Surgeon 2). On the femur, no significant differences in the distribution of intra-articular points could be demonstrated between the robotic system (2.1 mm), Fellow 1 (4.5 mm), Fellow 2 (4.1 mm), Experienced Surgeon 1 (2.3 mm), and Experienced Surgeon 2 (3.0 mm). The direction of the tunnels drilled in the femur and tibia was different with the robotic and traditional techniques. However, the robotic system had the most consistent tunnel directions, while the surgeons' tunnels were more dispersed. Variation in surgeon precision of tunnel placement for ACL reconstruction is greater on the femur than the tibia, and this can be correlated with experience. Our data also suggest that the robotic system has the same precision as the most experienced surgeons. PMID:11892003

  12. Preconditioning methods for improved convergence rates in iterative reconstructions

    SciTech Connect

    Clinthorne, N.H.; Chiao, Pingchun; Rogers, W.L. . Div. of Nuclear Medicine); Pan, T.S. . Dept. of Nuclear Medicine); Stamos, J.A. . Dept. of Nuclear Engineering)

    1993-03-01

    Because of the characteristics of the tomographic inversion problem, iterative reconstruction techniques often suffer from poor convergence rates--especially at high spatial frequencies. By using preconditioning methods, the convergence properties of most iterative methods can be greatly enhanced without changing their ultimate solution. To increase reconstruction speed, the authors have applied spatially-invariant preconditioning filters that can be designed using the tomographic system response and implemented using 2-D frequency-domain filtering techniques. In a sample application, the authors performed reconstructions from noiseless, simulated projection data, using preconditioned and conventional steepest-descent algorithms. The preconditioned methods demonstrated residuals that were up to a factor of 30 lower than the unassisted algorithms at the same iteration. Applications of these methods to regularized reconstructions from projection data containing Poisson noise showed similar, although not as dramatic, behavior.

  13. Reconstruction-classification method for quantitative photoacoustic tomography.

    PubMed

    Malone, Emma; Powell, Samuel; Cox, Ben T; Arridge, Simon

    2015-01-01

    We propose a combined reconstruction-classification method for simultaneously recovering absorption and scattering in turbid media from images of absorbed optical energy. This method exploits knowledge that optical parameters are determined by a limited number of classes to iteratively improve their estimate. Numerical experiments show that the proposed approach allows for accurate recovery of absorption and scattering in two and three dimensions, and delivers superior image quality with respect to traditional reconstruction-only approaches. PMID:26662815

  14. Reconstruction-classification method for quantitative photoacoustic tomography.

    PubMed

    Malone, Emma; Powell, Samuel; Cox, Ben T; Arridge, Simon

    2015-01-01

    We propose a combined reconstruction-classification method for simultaneously recovering absorption and scattering in turbid media from images of absorbed optical energy. This method exploits knowledge that optical parameters are determined by a limited number of classes to iteratively improve their estimate. Numerical experiments show that the proposed approach allows for accurate recovery of absorption and scattering in two and three dimensions, and delivers superior image quality with respect to traditional reconstruction-only approaches.

  15. An Ambulatory Method of Identifying Anterior Cruciate Ligament Reconstructed Gait Patterns

    PubMed Central

    Patterson, Matthew R.; Delahunt, Eamonn; Sweeney, Kevin T.; Caulfield, Brian

    2014-01-01

    The use of inertial sensors to characterize pathological gait has traditionally been based on the calculation of temporal and spatial gait variables from inertial sensor data. This approach has proved successful in the identification of gait deviations in populations where substantial differences from normal gait patterns exist; such as in Parkinsonian gait. However, it is not currently clear if this approach could identify more subtle gait deviations, such as those associated with musculoskeletal injury. This study investigates whether additional analysis of inertial sensor data, based on quantification of gyroscope features of interest, would provide further discriminant capability in this regard. The tested cohort consisted of a group of anterior cruciate ligament reconstructed (ACL-R) females and a group of non-injured female controls, each performed ten walking trials. Gait performance was measured simultaneously using inertial sensors and an optoelectronic marker based system. The ACL-R group displayed kinematic and kinetic deviations from the control group, but no temporal or spatial deviations. This study demonstrates that quantification of gyroscope features can successfully identify changes associated with ACL-R gait, which was not possible using spatial or temporal variables. This finding may also have a role in other clinical applications where small gait deviations exist. PMID:24451464

  16. An ambulatory method of identifying anterior cruciate ligament reconstructed gait patterns.

    PubMed

    Patterson, Matthew R; Delahunt, Eamonn; Sweeney, Kevin T; Caulfield, Brian

    2014-01-01

    The use of inertial sensors to characterize pathological gait has traditionally been based on the calculation of temporal and spatial gait variables from inertial sensor data. This approach has proved successful in the identification of gait deviations in populations where substantial differences from normal gait patterns exist; such as in Parkinsonian gait. However, it is not currently clear if this approach could identify more subtle gait deviations, such as those associated with musculoskeletal injury. This study investigates whether additional analysis of inertial sensor data, based on quantification of gyroscope features of interest, would provide further discriminant capability in this regard. The tested cohort consisted of a group of anterior cruciate ligament reconstructed (ACL-R) females and a group of non-injured female controls, each performed ten walking trials. Gait performance was measured simultaneously using inertial sensors and an optoelectronic marker based system. The ACL-R group displayed kinematic and kinetic deviations from the control group, but no temporal or spatial deviations. This study demonstrates that quantification of gyroscope features can successfully identify changes associated with ACL-R gait, which was not possible using spatial or temporal variables. This finding may also have a role in other clinical applications where small gait deviations exist.

  17. Reconstruction methods for phase-contrast tomography

    SciTech Connect

    Raven, C.

    1997-02-01

    Phase contrast imaging with coherent x-rays can be distinguished in outline imaging and holography, depending on the wavelength {lambda}, the object size d and the object-to-detector distance r. When r << d{sup 2}{lambda}, phase contrast occurs only in regions where the refractive index fastly changes, i.e. at interfaces and edges in the sample. With increasing object-to-detector distance we come in the area of holographic imaging. The image contrast outside the shadow region of the object is due to interference of the direct, undiffracted beam and a beam diffracted by the object, or, in terms of holography, the interference of a reference wave with the object wave. Both, outline imaging and holography, offer the possibility to obtain three dimensional information of the sample in conjunction with a tomographic technique. But the data treatment and the kind of information one can obtain from the reconstruction is different.

  18. The female ACL: why is it more prone to injury?

    PubMed

    Ireland, Mary Lloyd

    2002-10-01

    Multiple factors are responsible for ACL tears. The key factor in the gender discrepancy appears to be dynamic, not static, and proximal, not distal. The factors involved in evaluating the female ACL are multiple. However, it is the dynamic movement patterns ot hip and knee position with increased flexion and a coordinated proximal muscle firing pattern to keep the body in a safe landing position that are the most critical factors. An ACL injury at an early age is a life-changing event. We can very successfully reconstruct and rehabilitate an ACL, but we cannot stop there. We must now go into the prevention arena. In the United States there is tremendous variation in the exposure and acquisition of skills of physical activities in our youth. Today, children are often playing inside, using computers and watching television-missing out on the opportunity to learn safe movement patterns. Therefore, physical movement classes should occur very early in life, teaching children to land safely and in control, similar to the cry of "get down, stay down" routinely heard during youth soccer. Similarly, specific strength training programs can address landing as well as foot movements during cutting in basketball. Coaches should issue stern warnings when athletes demonstrate a high-risk movement patterns such as one-leg landings, out-of-control baseline landings, or straight-leg landings. The warnings may serve to keep the athlete from "touching the hot stove again" for fear of getting burned. No athlete feels she will be the one to get injured. Therefore, prospective analysis is likely to be received more warmly by the athletes if the program is presented with an emphasis on performance improvement rather than injury prevention. With increased participation in these programs, multiple-center analysis will have the power necessary to determine which factors significantly predispose athletes to ACL injury. The future for injury prevention is bright. We must rise to the challenge.

  19. Unilateral Stance Strategies of Athletes With ACL Deficiency

    PubMed Central

    Di Stasi, Stephanie L.; Hartigan, Erin H.; Snyder-Mackler, Lynn

    2013-01-01

    Aberrant movement strategies are characteristic of ACL-deficient athletes with recurrent knee instability (non-copers), and may instigate premature or accelerate joint degradation. Biomechanical evaluation of kinematic changes over time may elucidate noncopers’ responses to neuromuscular intervention and ACL reconstruction (ACLR). Forty noncopers were randomized into a perturbation group or a strength training only group. We evaluated the effects of perturbation training, and then gender on knee angle and tibial position during a unilateral standing task before and after ACLR. No statistically significant interactions were found. Before surgery, the strength training only group demonstrated knee angle asymmetry, but 6 months after ACLR, both groups presented with similar knee flexion between limbs. Aberrant and asymmetrical tibial position was found only in females following injury and ACLR. Neither treatment group showed distinct unilateral standing strategies following intervention; however, males and female noncopers appear to respond uniquely to physical therapy and surgery. PMID:22983931

  20. Electrospinning polymer blends for biomimetic scaffolds for ACL tissue engineering

    NASA Astrophysics Data System (ADS)

    Garcia, Vanessa Lizeth

    The anterior cruciate ligament (ACL) rupture is one of the most common knee injuries. Current ACL reconstructive strategies consist of using an autograft or an allograft to replace the ligament. However, limitations have led researchers to create tissue engineered grafts, known as scaffolds, through electrospinning. Scaffolds made of natural and synthetic polymer blends have the potential to promote cell adhesion while having strong mechanical properties. However, enzymes found in the knee are known to degrade tissues and affect the healing of intra-articular injuries. Results suggest that the natural polymers used in this study modify the thermal properties and tensile strength of the synthetic polymers when blended. Scanning electron microscopy display bead-free and enzyme biodegradability of the fibers. Raman spectroscopy confirms the presence of the natural and synthetic polymers in the scaffolds while, amino acid analysis present the types of amino acids and their concentrations found in the natural polymers.

  1. Association Between Meniscal and Chondral Lesions and Timing of Anterior Cruciate Ligament Reconstruction

    PubMed Central

    de Campos, Gustavo Constantino; Nery, Wilton; Teixeira, Paulo Eduardo Portes; Araujo, Paulo Henrique; Alves, Wilson de Mello

    2016-01-01

    Background: Rupture of the anterior cruciate ligament (ACL) is a common sports injury and is known to be associated with an increased risk of knee osteoarthritis. Several studies have indicated that the risk of additional injuries to the menisci and articular cartilage increases with delays in the treatment of ACL tears. However, no consensus has been reached regarding the ideal timing for ACL reconstruction in terms of preventing secondary lesions. Purpose: To determine how the time elapsed between an ACL lesion and its reconstruction affects the incidence of meniscal and chondral lesions. Study Design: Case series; Level of evidence, 4. Methods: Medical records of 764 patients who underwent primary ACL reconstruction were reviewed. Data from arthroscopic findings that included information about meniscal lesions and full-thickness articular cartilage lesions at the time of surgery were collected. The association between time elapsed between ACL lesion and reconstruction surgery and incidence of articular cartilage and meniscal lesions was analyzed by chi-square or Fisher exact test. The risk of secondary lesion was calculated by odds ratios (ORs) obtained from simple logistic regression analysis. Results: A positive correlation was observed between time after injury and the presence of any articular lesions (P = .003), cartilage lesions (P = .01), and medial meniscus lesions (P < .001). When analyzing the risk of secondary lesion relative to the reference period (<2 months), it was observed that the odds of finding any articular injury at the time of ACL reconstruction increased when the time from ACL injury to surgery was between 12 and 24 months (OR = 2.62) and >24 months (OR = 5.88). Furthermore, the odds of lesions on the medial meniscus increased when the timing between injury and surgery was 6 to 12 months (OR = 2.71) and continued to increase when the timing was 12 to 24 months (OR = 3.78) and >24 months (OR = 9.07). Conclusion: Associated articular lesions

  2. Reconstruction of radiating sound fields using minimum energy method.

    PubMed

    Bader, Rolf

    2010-01-01

    A method for reconstructing a pressure field at the surface of a radiating body or source is presented using recording data of a microphone array. The radiation is assumed to consist of many spherical radiators, as microphone positions are present in the array. These monopoles are weighted using a parameter alpha, which broadens or narrows the overall radiation directivity as an effective and highly intuitive parameter of the radiation characteristics. A radiation matrix is built out of these weighted monopole radiators, and for different assumed values of alpha, a linear equation solver reconstructs the pressure field at the body's surface. It appears that from these many arbitrary reconstructions, the correct one minimizes the reconstruction energy. The method is tested, localizing the radiation points of a Balinese suling flute, reconstructing complex radiation from a duff frame drum, and determining the radiation directivity for the first seven modes of an Usbek tambourine. Stability in terms of measurement noise is demonstrated for the plain method, and additional highly effective algorithm is added for a noise level up to 0 dB. The stability of alpha in terms of minimal reconstruction energy is shown over the whole range of possible values for alpha. Additionally, the treatment of unwanted room reflections is discussed, still leading to satisfactory results in many cases. PMID:20058977

  3. Gait and Neuromuscular Asymmetries after Acute ACL Rupture

    PubMed Central

    Gardinier, Emily S.; Manal, Kurt; Buchanan, Thomas S.; Snyder-Mackler, Lynn

    2012-01-01

    The decreased internal knee extensor moment is a significant gait asymmetry among patients with anterior cruciate ligament (ACL) deficiency, yet the muscular strategy driving this altered moment for the injured limb is unclear. Purpose To determine whether patients with ACL deficiency and characteristic knee instability would demonstrate normal extensor and increased flexor muscle force to generate a decreased internal extensor moment (i.e. employ a hamstring facilitation strategy). Methods Gait analysis was performed on 31 athletes with acute ACL rupture who exhibited characteristic knee instability after injury. Peak internal knee extensor moment was calculated using inverse dynamics and muscle forces were estimated using an EMG-driven modeling approach. Comparisons were made between the injured and contralateral limbs. Results As expected, patients demonstrated decreased peak knee flexion (p=0.028) and internal knee extensor moment (p=0.0004) for their injured limb, but exhibited neither an isolated decrease in extensor force (quadriceps avoidance), nor an isolated increase in flexor force (hamstring facilitation) at peak knee moment. Instead, they exhibited decreased muscle force from both flexor (p=0.0001) and extensor (p=0.0103) groups. This strategy of decreased muscle force may be explained in part by muscle weakness which frequently accompanies ACL injury, or by apprehension, low confidence and fear of further injury. Conclusions This is the first study to estimate muscle forces in the ACL-deficient knee using an EMG-driven approach. These results affirm the existence of neuromuscular asymmetries in the individuals with ACL deficiency and characteristic knee instability. PMID:22330021

  4. A Comparison of Methods for Ocean Reconstruction from Sparse Observations

    NASA Astrophysics Data System (ADS)

    Streletz, G. J.; Kronenberger, M.; Weber, C.; Gebbie, G.; Hagen, H.; Garth, C.; Hamann, B.; Kreylos, O.; Kellogg, L. H.; Spero, H. J.

    2014-12-01

    We present a comparison of two methods for developing reconstructions of oceanic scalar property fields from sparse scattered observations. Observed data from deep sea core samples provide valuable information regarding the properties of oceans in the past. However, because the locations of sample sites are distributed on the ocean floor in a sparse and irregular manner, developing a global ocean reconstruction is a difficult task. Our methods include a flow-based and a moving least squares -based approximation method. The flow-based method augments the process of interpolating or approximating scattered scalar data by incorporating known flow information. The scheme exploits this additional knowledge to define a non-Euclidean distance measure between points in the spatial domain. This distance measure is used to create a reconstruction of the desired scalar field on the spatial domain. The resulting reconstruction thus incorporates information from both the scattered samples and the known flow field. The second method does not assume a known flow field, but rather works solely with the observed scattered samples. It is based on a modification of the moving least squares approach, a weighted least squares approximation method that blends local approximations into a global result. The modifications target the selection of data used for these local approximations and the construction of the weighting function. The definition of distance used in the weighting function is crucial for this method, so we use a machine learning approach to determine a set of near-optimal parameters for the weighting. We have implemented both of the reconstruction methods and have tested them using several sparse oceanographic datasets. Based upon these studies, we discuss the advantages and disadvantages of each method and suggest possible ways to combine aspects of both methods in order to achieve an overall high-quality reconstruction.

  5. Baseline Predictors of Health-Related Quality of Life After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Dunn, Warren R.; Wolf, Brian R.; Harrell, Frank E.; Reinke, Emily K.; Huston, Laura J.; Spindler, Kurt P.; Nwosu, Samuel K.; Kaeding, Christopher C.; Parker, Richard D.; Wright, Rick W.; Andrish, Jack T.; McCarty, Eric C.; Amendola, Annunziato; Marx, Robert G.; Wolcott, Michelle L.; Liu, Zhouwen; Alvarez, JoAnn M.

    2015-01-01

    Background: Limited information exists regarding predictors of general quality of life following anterior cruciate ligament (ACL) reconstruction with up to six-year follow-up. We hypothesized that certain variables evaluated at the time of ACL reconstruction will predict the general quality of life as measured by the Short Form-36 (SF-36). Methods: All unilateral ACL reconstructions from 2002 to 2004 in patients currently enrolled in a prospective multicenter cohort were evaluated. Patients preoperatively completed the SF-36 validated outcome instrument. Surgeons documented intra-articular pathological conditions and treatment, as well as the ACL reconstruction surgical technique. At baseline and at a minimum of two and six years postoperatively, patients completed the SF-36. Longitudinal analysis was performed for the two-year and six-year end points. Results: Of the initial 1512 subjects, at least one follow-up questionnaire was obtained from 1411 subjects (93%). The cohort was 44% female, and the median patient age at enrollment was twenty-three years. The mean scores were 41.9 points for the Physical Component Summary (PCS) and 51.7 points for the Mental Component Summary (MCS) at baseline, 53.6 points for the PCS and 52.0 points for the MCS at two years, and 54.0 points for the PCS and 52.4 points for the MCS at six years. Significant predictors of a higher PCS score were a higher baseline PCS score, younger age, lower baseline body mass index, having >50% of the lateral meniscus excised, or having no treatment done on a lateral meniscal tear. In contrast, significant predictors of a lower PCS score were a shorter follow-up time since surgery, revision ACL reconstruction, smoking at baseline, fewer years of education, and chondromalacia of the lateral tibial plateau. The mean utility gained at six years after ACL reconstruction was 5.3 quality-adjusted life years (QALYs). Conclusions: Large improvements in the PCS (with an effect size of 1.2) were noted at two

  6. Cheng's method for reconstruction of a functionally sensitive penis.

    PubMed

    Cheng, K X; Zhang, R H; Zhou, S; Jiang, K C; Eid, A E; Huang, W Y

    1997-01-01

    This article introduces a new surgical method for one-stage reconstruction of the penis. It is applied to the reconstruction of the microphallus as well as to traumatic cases with the residual stump of the amputated penis not less than 3 cm long. By transferring the original glans or the residual penile stump to the anterior portion of the newly reconstructed penile body with microsurgical techniques, we have thus rebuilt a penis with more satisfactory results in both appearance and erotic sensation. Seven patients are reported here who were operated on by this method and who have been followed up for 18 months to 10 years. The good results achieved and the method's advantages over other methods are demonstrated and discussed. PMID:8982190

  7. Factors Associated with Infection Following Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Brophy, Robert H.; Wright, Rick W.; Huston, Laura J.; Nwosu, Samuel K.; Spindler, Kurt P.

    2015-01-01

    Background: Although rare, infection can be devastating after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to test the association between infection after ACL reconstruction and potential risk factors such as age, body mass index (BMI), smoking, diabetes, and graft choice. Methods: We reviewed the Multicenter Orthopaedic Outcomes Network (MOON) cohort from 2002 to 2005 to identify patients with a postoperative infection. The age, BMI, smoking status, history of diabetes, and graft choice were recorded for each patient. A multivariable regression analysis was constructed to examine which baseline risk factors were independently associated with postoperative infection after ACL reconstruction requiring surgical intervention. Results: There were 2198 eligible patients in the cohort, with seventeen (0.8%) reporting a postoperative infection. Diabetes was found to be a significant risk factor for infection (odds ratio [OR] = 18.8; 95% confidence interval [CI] = 3.8 to 94.0; p < 0.001). Compared with bone-tendon-bone autograft, both hamstring autograft and other grafts (e.g., the majority of allografts, with some that were both autograft and allograft) also increased the risk of infection (OR = 4.6 [95% CI = 1.2 to 17.9; p = 0.026] for hamstrings and 4.3 [95% CI = 1.0 to 18.1; p = 0.047] for other grafts). Although the OR for infection in smokers was 2.5, this finding did not reach significance. Conclusions: Patients with diabetes undergoing ACL reconstruction have a significantly elevated risk of postoperative infection (18.8-times higher odds) compared with that for patients without diabetes. Use of bone-tendon-bone autograft is associated with a lower risk of infection after ACL reconstruction. Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence. PMID:25788300

  8. Histopathological Changes in the Human Posterior Cruciate Ligament During Aging and Osteoarthritis: Correlations with ACL and Cartilage Changes

    PubMed Central

    Levy, Yadin D.; Hasegawa, Akihiko; Patil, Shantanu; Koziol, James A.; Lotz, Martin K.; D’Lima, Darryl D.

    2012-01-01

    Objectives To determine the histological patterns of posterior cruciate ligament (PCL) degeneration during aging and in relation to changes in articular cartilage and anterior cruciate ligament (ACL) across the entire adult age spectrum. Methods Human knee joints (n=120 from 65 donors) were processed within 72 hours postmortem. Articular cartilage surfaces were graded macroscopically. Each PCL was histologically evaluated for inflammation, mucinous changes, chondroid metaplasia, cystic changes and orientation of collagen fibers. Severity of PCL degeneration was classified as normal, mild, moderate or severe. PCL scores were compared to ACL and cartilage scores from the same knees. Results All knees had intact PCL. Histologically, 6% were normal, 76% showed mild, 12% moderate and 9% severe degeneration. Fiber disorientation was the most prevalent and severe change. Histological grades of PCL and ACL correlated but significantly fewer PCL than ACL showed severe changes. There was weaker correlation between aging and total histological PCL scores (R=0.26) compared to aging and ACL scores (R=0.42). ACL scores correlated with cartilage scores (R=0.54) while PCL scores increased with severity of OA from grades 0 to III but not between OA grades III to IV (R=0.32). In knees with ruptured ACL, the PCL scores correlated with cartilage scores of the lateral compartment. Conclusions PCL histopathological changes are less severe than in the ACL. PCL degeneration was associated with ACL and cartilage damage. The lack of correlation with age indicates independent pathways for PCL versus ACL degeneration. PMID:22872023

  9. Anterior cruciate ligament- specialized post-operative return-to-sports (ACL-SPORTS) training: a randomized control trial

    PubMed Central

    2013-01-01

    Background Anterior cruciate ligament reconstruction (ACLR) is standard practice for athletes that wish to return to high-level activities; however functional outcomes after ACLR are poor. Quadriceps strength weakness, abnormal movement patterns and below normal knee function is reported in the months and years after ACLR. Second ACL injuries are common with even worse outcomes than primary ACLR. Modifiable limb-to-limb asymmetries have been identified in individuals who re-injure after primary ACLR, suggesting a neuromuscular training program is needed to improve post-operative outcomes. Pre-operative perturbation training, a neuromuscular training program, has been successful at improving limb symmetry prior to surgery, though benefits are not lasting after surgery. Implementing perturbation training after surgery may be successful in addressing post-operative deficits that contribute to poor functional outcomes and second ACL injury risk. Methods/Design 80 athletes that have undergone a unilateral ACLR and wish to return to level 1 or 2 activities will be recruited for this study and randomized to one of two treatment groups. A standard care group will receive prevention exercises, quadriceps strengthening and agility exercises, while the perturbation group will receive the same exercise program with the addition of perturbation training. The primary outcomes measures will include gait biomechanics, clinical and functional measures, and knee joint loading. Return to sport rates, return to pre-injury level of activity rates, and second injury rates will be secondary measures. Discussion The results of this ACL-Specialized Post-Operative Return To Sports (ACL-SPORTS) Training program will help clinicians to better determine an effective post-operative treatment program that will improve modifiable impairments that influence outcomes after ACLR. Trial registration Randomized Control Trial NIH 5R01AR048212-07. ClinicalTrials.gov: NCT01773317 PMID:23522373

  10. Systematic Review of Biological Modulation of Healing in Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Fu, Sai-Chuen; Cheuk, Yau-Chuk; Yung, Shu-Hang; Rolf, Christer Gustav; Chan, Kai-Ming

    2014-01-01

    Background: Whether biological modulation is effective to promote healing in anterior cruciate ligament (ACL) reconstruction remains unclear. Purpose: To perform a systematic review of both clinical and experimental evidence of preclinical animal studies on biological modulation to promote healing in ACL reconstruction. Study Design: Systematic review; Level of evidence, 2. Methods: A systematic search was performed using the PubMed, Ovid, and Scopus search engines. Inclusion criteria were clinical and animal studies involving subjects with ACL injury with the use of biological modulation to promote healing outcomes. Methodological quality of clinical studies was evaluated using the Critical Appraisal Skill Programme (CASP) appraisal tool, and animal studies were evaluated by a scoring system based on a published checklist of good animal studies. Results: Ten clinical studies and 50 animal studies were included. Twenty-five included studies were regarded as good quality, with a methodological score ≥5. These studies suggested that transforming growth factor–beta (TGF-β), mesenchymal stem cells, osteogenic factors, and modalities that reduce local inflammation may be beneficial to promote graft healing in ACL reconstruction. Conclusion: This systematic review suggests that biological modulation is able to promote healing on top of surgical treatment for ACL injuries. This treatment strategy chiefly works through promotion of healing at the tunnel-graft interface, but the integrity of the intra-articular midsubstance of the graft would be another target for biological modulation. PMID:26535311

  11. Sex, Age, and Graft Size as Predictors of ACL Re-tear

    PubMed Central

    Nguyen, Duong

    2016-01-01

    Objectives: The minimum size required for a successful quadrupled hamstring autograft ACL reconstruction remains controversial. The risks of ACL re-tear in younger patients who tend to participate in a higher level of sports activity, and female athletes who have numerous predisposing factors, are poorly defined. Purpose: To identify risk factors for graft re-tears within 2 years of ACL surgery. The hypotheses are that female sex, a smaller size graft, and younger patients will increase the odds of failure. Study Design Cohort Study. Level of evidence, 3. Methods: A cohort of 503 athletes undergoing primary, autograft hamstring ACL reconstruction, performed by a single surgeon using the same surgical technique and rehabilitation protocol, between September-December 2012, was followed for a total duration of 2 years. Return to play was allowed between 6 and 12 months post-surgery upon completion of functional testing. Exclusion criteria included infections, revisions, double bundle techniques, multi-ligament injuries, non-compliance, BTB/allografts/hybrid grafts. Primary outcome consisted of binary data (ACL graft re-tear or no tear) as measured on physical exam (Lachman and pivot shift) and MRI. Multivariate logistic regression statistical analysis with model fitting was used to investigate the predictive value of sex, age, and graft size on ACL re-tear. Secondary sensitivity analyses were performed on the adolescent subgroup, age and graft size as categorical variables, and testing for interactions among variables. Sample size was calculated based on the rule of 10 events per independent variable for logistic regression. Results: The mean age of the 503 athletes was 27.5 (SD 10.6; range = 12-61). There were 235 females (47%) and 268 males (53%) with a 6% rate of re-tears (28 patients; 17 females). Mean graft size was 7.9 (SD 0.6; range = 6-10). Univariate analyses of graft size, sex, and age only in the model showed that younger age (odds ratio [OR] = 0.86; 95

  12. Multicenter Orthopaedic Outcome Network Early Anti-inflammatory Treatment in Patients with Acute ACL Tear” (MOON-AAA) Clinical Trial

    PubMed Central

    Lattermann, Christian; Proffitt, Mary; Huston, Laura J.; Gammon, Lee; Johnson, Darren L.; Kraus, Virginia B.; Spindler, Kurt P.

    2016-01-01

    Objectives: We present the early results from the “Multicenter Orthopaedic Outcome Network Early Anti-inflammatory Treatment in Patients with Acute ACL Tear and Painful Effusions” (MOON-AAA) clinical trial (figure 1). This trial allows for a well controlled prospective cohort of patients with isolated ACL injury at risk for OA. We compared the effect of a single versus a repeated dosage of Kenalog within the first two weeks after ACL injury and its effect on chondral degradation in the first 4 weeks prior to surgical reconstruction of the ACL. Methods: 49 patients with isolated ACL tears were enrolled. Knee joints were aspirated and patients received an injection with 40 mg Kenalog either within 4 days, 10 days, both time points or not at all (saline injection control). Serum, synovial fluid and urine were collected at 3 time points. Permutated block randomization, triple blinding, independent monitoring and standardized x-ray was performed to comply with GCP standards. Patient reported outcomes were collected at 6 time points up to 6 months post-ACL reconstruction(IKDC, KOOS and Marx activity level). A standardized synovial fluid biomarker panel was analyzed according to OARSI guidelines. Statistical analysis were performed using SAS mixed models analysis. Results: Serum analysis shows significant change after injury. Chondrodegradatory markers such as CTX-II, MMP-1 and MMP-3 as well as COMP indicate a progressive destruction of chondral matrix and collagen breakdown . There is a dramatic (250%) increase of CTX-II in the first 4 weeks. Matrix proteins such as MMP-1 and 3 as well as COMP show an initial increase and then a steep decline (see figure 1). Inflammatory markers (IL-1 alpha, IL-1beta, IRAP) show a decline from the time of injury. IL-1 alpha, however shows a dramatic uptake after week 2. This longitudinal data confirms a dramatic onset of early osteoarthritic biomarker profiles immediately after ACL injury as measured in synovial fluid

  13. Long-term Outcomes After Anterior Cruciate Ligament Reconstruction in Patients 60 Years and Older

    PubMed Central

    Baker, Champ L.; Jones, Jaclyn C.; Zhang, Jeff

    2014-01-01

    Background: Studies evaluating the benefit of surgical reconstruction of the anterior cruciate ligament (ACL) in middle-aged patients have shown promising results, but study populations were limited primarily to patients who were 40 to 60 years old. Some authors have suggested that surgery may benefit these older patients. Hypothesis: Patients aged ≥60 years with functional instability after ACL injury would benefit from ACL reconstruction. Study Design: Case series; Level of evidence, 4. Methods: Medical records from 1984 through 2010 were searched for patients aged ≥60 years who had undergone primary arthroscopic ACL reconstruction at a single institution. Fifteen patients (15 knees) were identified as meeting the above criteria. All patients were contacted for a telephone interview, and they completed Short Form–36 and modified Cincinnati Knee Score forms. One patient was deceased, and 1 had undergone revision to total knee arthroplasty. Among the remaining 13 patients, the mean age at surgery was 63.5 years (range, 60-73 years), and the mean patient age at the time of follow-up was 73 years (range, 65-85 years). Preoperative radiographs showed no obvious evidence of arthritis in 10 (77%) of the 13 patients; small osteophytes without loss of joint space were seen in 3 (23%) patients. The mean length of follow up was 115.7 months (range, 53-193 months). Results: At their last clinic visits, all 13 patients had regained full range of motion and returned to sports or exercise, such as tennis, golf, gym exercise, and yoga. Twelve patients reported no joint laxity. Conclusion: Patients aged ≥60 years with symptomatic instability from ACL injury can have good to excellent subjective outcomes with surgical reconstruction. Clinical Relevance: Physicians who treat active patients older than 60 years should not exclude ACL reconstruction based on the patient’s age alone. PMID:26535289

  14. Revision Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Wilde, Jeffrey; Bedi, Asheesh; Altchek, David W.

    2014-01-01

    Context: Reconstruction of the anterior cruciate ligament (ACL) is one of the most common surgical procedures, with more than 200,000 ACL tears occurring annually. Although primary ACL reconstruction is a successful operation, success rates still range from 75% to 97%. Consequently, several thousand revision ACL reconstructions are performed annually and are unfortunately associated with inferior clinical outcomes when compared with primary reconstructions. Evidence Acquisition: Data were obtained from peer-reviewed literature through a search of the PubMed database (1988-2013) as well as from textbook chapters and surgical technique papers. Study Design: Clinical review. Level of Evidence: Level 4. Results: The clinical outcomes after revision ACL reconstruction are largely based on level IV case series. Much of the existing literature is heterogenous with regard to patient populations, primary and revision surgical techniques, concomitant ligamentous injuries, and additional procedures performed at the time of the revision, which limits generalizability. Nevertheless, there is a general consensus that the outcomes for revision ACL reconstruction are inferior to primary reconstruction. Conclusion: Excellent results can be achieved with regard to graft stability, return to play, and functional knee instability but are generally inferior to primary ACL reconstruction. A staged approach with autograft reconstruction is recommended in any circumstance in which a single-stage approach results in suboptimal graft selection, tunnel position, graft fixation, or biological milieu for tendon-bone healing. Strength-of-Recommendation Taxonomy (SORT): Good results may still be achieved with regard to graft stability, return to play, and functional knee instability, but results are generally inferior to primary ACL reconstruction: Level B. PMID:25364483

  15. A fast-convergence POCS seismic denoising and reconstruction method

    NASA Astrophysics Data System (ADS)

    Ge, Zi-Jian; Li, Jing-Ye; Pan, Shu-Lin; Chen, Xiao-Hong

    2015-06-01

    The efficiency, precision, and denoising capabilities of reconstruction algorithms are critical to seismic data processing. Based on the Fourier-domain projection onto convex sets (POCS) algorithm, we propose an inversely proportional threshold model that defines the optimum threshold, in which the descent rate is larger than in the exponential threshold in the large-coefficient section and slower than in the exponential threshold in the small-coefficient section. Thus, the computation efficiency of the POCS seismic reconstruction greatly improves without affecting the reconstructed precision of weak reflections. To improve the flexibility of the inversely proportional threshold, we obtain the optimal threshold by using an adjustable dependent variable in the denominator of the inversely proportional threshold model. For random noise attenuation by completing the missing traces in seismic data reconstruction, we present a weighted reinsertion strategy based on the data-driven model that can be obtained by using the percentage of the data-driven threshold in each iteration in the threshold section. We apply the proposed POCS reconstruction method to 3D synthetic and field data. The results suggest that the inversely proportional threshold model improves the computational efficiency and precision compared with the traditional threshold models; furthermore, the proposed reinserting weight strategy increases the SNR of the reconstructed data.

  16. Tibial translation and muscle activation during rehabilitation exercises 5 weeks after anterior cruciate ligament reconstruction.

    PubMed

    Tagesson, S; Oberg, B; Kvist, J

    2010-02-01

    The aim of this study was to compare different rehabilitation exercises with respect to dynamic anterior tibial translation and muscle activation 5 weeks after an anterior cruciate ligament (ACL) reconstruction. Another aim was to compare the ACL-reconstructed knee with the ACL-injured and the uninjured knees for differences in anterior tibial translation and muscle activation during the exercises. Sagittal tibial translation and muscle activation were measured during the Lachman test (static translation) and during seven rehabilitation exercises (dynamic translation) in 19 patients. Results obtained 5 weeks after ACL reconstruction were compared with those obtained before the ACL reconstruction (ACL-deficient and uninjured knee). After ACL reconstruction the seated knee extension produced more anterior tibial translation than the straight leg raise and standing on one leg. The ACL reconstruction reduced the static and the dynamic tibial translation and the tibial translations measured in ACL-reconstructed knees were similar to those measured in uninjured knees. After ACL reconstruction, the patients used a joint stiffening strategy that used more hamstring activation and reduced the dynamic tibial translation. Although all exercises tested are suitable for rehabilitation after ACL reconstruction, to protect the graft from excessive strain, the straight leg raise and squat on one leg are preferable for quadriceps training in the early phase of rehabilitation.

  17. MR Image Reconstruction Using Block Matching and Adaptive Kernel Methods

    PubMed Central

    Schmidt, Johannes F. M.; Santelli, Claudio; Kozerke, Sebastian

    2016-01-01

    An approach to Magnetic Resonance (MR) image reconstruction from undersampled data is proposed. Undersampling artifacts are removed using an iterative thresholding algorithm applied to nonlinearly transformed image block arrays. Each block array is transformed using kernel principal component analysis where the contribution of each image block to the transform depends in a nonlinear fashion on the distance to other image blocks. Elimination of undersampling artifacts is achieved by conventional principal component analysis in the nonlinear transform domain, projection onto the main components and back-mapping into the image domain. Iterative image reconstruction is performed by interleaving the proposed undersampling artifact removal step and gradient updates enforcing consistency with acquired k-space data. The algorithm is evaluated using retrospectively undersampled MR cardiac cine data and compared to k-t SPARSE-SENSE, block matching with spatial Fourier filtering and k-t ℓ1-SPIRiT reconstruction. Evaluation of image quality and root-mean-squared-error (RMSE) reveal improved image reconstruction for up to 8-fold undersampled data with the proposed approach relative to k-t SPARSE-SENSE, block matching with spatial Fourier filtering and k-t ℓ1-SPIRiT. In conclusion, block matching and kernel methods can be used for effective removal of undersampling artifacts in MR image reconstruction and outperform methods using standard compressed sensing and ℓ1-regularized parallel imaging methods. PMID:27116675

  18. Anterior cruciate ligament reconstruction and rehabilitation: predictors of functional outcome

    PubMed Central

    DELLA VILLA, FRANCESCO; RICCI, MARGHERITA; PERDISA, FRANCESCO; FILARDO, GIUSEPPE; GAMBERINI, JACOPO; CAMINATI, DANIELE; DELLA VILLA, STEFANO

    2015-01-01

    Surgical reconstruction of an injured anterior cruciate ligament (ACL) leads to full recovery of function and sports activity in a high percentage of cases. The aim of the present study was to analyze variables related to the patient, the surgical technique and the post-surgical rehabilitation methods, seeking to identify predictors of outcome and recovery time after ACL reconstruction. One hundred and four patients (81 M, 23 F) undergoing a step-based rehabilitation protocol after ACL reconstruction were evaluated. 43.2% of them had an isolated ACL lesion, whereas 56.8% had one or more concurrent injuries. Data relating to personal characteristics, surgery and post-operative management were collected and analyzed for correlation. Clinical outcome was evaluated with IKDC subjective score and the Tegner score, and the time to reach full recovery was noted as well. Young patients with a higher pre-injury Tegner activity level or who practice sport at professional level, no concurrent capsular lesions and no postoperative knee bracing had better clinical results and took shorter time to recover. Also, a higher percentage of on-the-field rehabilitation sessions, and absence of significant muscle strength deficits at the first knee isokinetic test emerged as rehabilitation-related factors leading to a better post-surgical outcome. Personal, surgical and rehabilitation factors should be considered in order to optimize patient management and maximize the expected results. Further studies are needed to find the strongest factors in different patients. Level of evidence Level IV, retrospective study. PMID:26904523

  19. Anterior Cruciate Ligament Reconstruction Using a Combination of Autograft and Allograft Tendon

    PubMed Central

    Darnley, James E.; Léger-St-Jean, Benjamin; Pedroza, Angela D.; Flanigan, David C.; Kaeding, Christopher C.; Magnussen, Robert A.

    2016-01-01

    Background: Anterior cruciate ligament (ACL) reconstruction with hamstring autografts less than 8.5 mm in diameter is associated with worse patient-reported outcome scores and increased risk of revision surgery compared with reconstructions performed with larger grafts. One proposed solution to small autograft harvest is to create a hybrid graft by augmenting autografts with allograft tissue to increase graft diameter. Purpose: To compare hybrid autograft/allograft ACL reconstruction to autograft ACL reconstruction, specifically analyzing the patient-reported outcome scores and the risk of revision surgery at 2 years postoperative. Study Design: Cohort study; Level of evidence, 3. Methods: From the years 2002 to 2009, a total of 34 patients were identified from a prospectively collected database as having undergone hybrid ACL reconstruction. Twenty-seven of 34 (79.4%) patients had a 2-year follow-up. These 27 patients were matched by age (within 1 year) and sex to 27 patients who underwent hamstring autograft ACL reconstruction during the same period. At the 2-year mark, revision surgery risk and patient-reported outcome scores were compared between the 2 groups. Results: The mean age for the hybrid and matched groups (±SD) was 20.9 ± 7.0 years. Both the hybrid and control groups had 17 males and 10 females. There was no significant difference in preoperative patient-reported outcome scores, meniscus tears, or cartilage lesions between the 2 groups. Graft size was larger in the hybrid group (9.5 ± 0.6 mm) than in the autograft group (8.4 ± 0.9 mm) (P < .001). At 2 years postoperative, patient-reported outcome scores were similar between the hybrid and autograft groups. Revision surgery was required in 5 (18.5%) patients who underwent hybrid reconstruction compared with 2 (7.4%) of those who underwent autograft reconstruction (P = .26). Conclusion: Patients who undergo ACL reconstruction with hybrid hamstring grafts and hamstring autografts report similar

  20. Outcome of Simultaneous Arthroscopic Anterior Cruciate Ligament and Posterior Cruciate Ligament Reconstruction With Hamstring Tendon Autograft: A Multicenter Prospective Study

    PubMed Central

    Panigrahi, Ranajit; Kumari Mahapatra, Amita; Priyadarshi, Ashok; Singha Das, Dibya; Palo, Nishit; Ranjan Biswal, Manas

    2016-01-01

    Background: Multiligamentous injuries of knee are a complex problem in orthopaedics. Combined ACL-PCL injuries are uncommon, usually associated with knee dislocations. Extremity vascular status is essential because of possible arterio-venous compromise. These complex injuries require a systematic evaluation and treatment. Single setting simultaneous arthroscopic ACL and PCL reconstruction or a staged approach can be adopted to treat these cases. Objectives: To evaluate functional outcome of simultaneous arthroscopic ACL and PCL reconstruction with hamstring tendon autograft in multiligamentous knee injuries. Patients and Methods: This prospective study was performed on 20 patients with combined ACL-PCL injuries who underwent simultaneous arthroscopic ACL-PCL reconstruction with hamstring tendon. Evaluation of functional outcome was by IKDC and Lysholm-Tegner scores. Results: In 20 patients, mean age 34 years, return to full-time work and to full sports was 8 weeks and 6.2 months respectively. All patients had full range of motion except 2 patients with < 5 degrees flexion loss; 90% had negative Lachmann test; 95% had negative pivot shift and 10% patients had mild posterior drawer at 90 degrees (1+) at final follow up. Mean IKDC score was 90 (range 81 - 94); mean Tegner activity score was 7 and mean Lysholm knee score was 89. 85% returned to preinjury activity level and a 90% satisfaction rate. Conclusions: Simultaneous arthroscopic ACL and PCL reconstructions using hamstring tendon for combined ACL and PCL injuries is a clinically effective, safe, time saving and cost-effective procedure with better patient compliance and reproducible for a timely return of motion, strength, and function with favorable outcome. PMID:27217932

  1. Tomographic fluorescence reconstruction by a spectral projected gradient pursuit method

    NASA Astrophysics Data System (ADS)

    Ye, Jinzuo; An, Yu; Mao, Yamin; Jiang, Shixin; Yang, Xin; Chi, Chongwei; Tian, Jie

    2015-03-01

    In vivo fluorescence molecular imaging (FMI) has played an increasingly important role in biomedical research of preclinical area. Fluorescence molecular tomography (FMT) further upgrades the two-dimensional FMI optical information to three-dimensional fluorescent source distribution, which can greatly facilitate applications in related studies. However, FMT presents a challenging inverse problem which is quite ill-posed and ill-conditioned. Continuous efforts to develop more practical and efficient methods for FMT reconstruction are still needed. In this paper, a method based on spectral projected gradient pursuit (SPGP) has been proposed for FMT reconstruction. The proposed method was based on the directional pursuit framework. A mathematical strategy named the nonmonotone line search was associated with the SPGP method, which guaranteed the global convergence. In addition, the Barzilai-Borwein step length was utilized to build the new step length of the SPGP method, which was able to speed up the convergence of this gradient method. To evaluate the performance of the proposed method, several heterogeneous simulation experiments including multisource cases as well as comparative analyses have been conducted. The results demonstrated that, the proposed method was able to achieve satisfactory source localizations with a bias less than 1 mm; the computational efficiency of the method was one order of magnitude faster than the contrast method; and the fluorescence reconstructed by the proposed method had a higher contrast to the background than the contrast method. All the results demonstrated the potential for practical FMT applications with the proposed method.

  2. ACLS.

    PubMed

    Handley, A J

    2001-09-01

    It must be emphasised that the published International Guidelines 2000 contain an in-depth presentation of the scientific evidence behind advanced life support. The exact interpretation of this evidence, and the algorithms adopted by a national resuscitation council will depend upon various factors such as local interpretation of the evidence, local practice and availability of drugs. The ERC is publishing its own summaries of the guideline changes and the sequences of action for both BLS and ALS and these papers are recommended for further reading.

  3. Bubble reconstruction method for wire-mesh sensors measurements

    NASA Astrophysics Data System (ADS)

    Mukin, Roman V.

    2016-08-01

    A new algorithm is presented for post-processing of void fraction measurements with wire-mesh sensors, particularly for identifying and reconstructing bubble surfaces in a two-phase flow. This method is a combination of the bubble recognition algorithm presented in Prasser (Nuclear Eng Des 237(15):1608, 2007) and Poisson surface reconstruction algorithm developed in Kazhdan et al. (Poisson surface reconstruction. In: Proceedings of the fourth eurographics symposium on geometry processing 7, 2006). To verify the proposed technique, a comparison was done of the reconstructed individual bubble shapes with those obtained numerically in Sato and Ničeno (Int J Numer Methods Fluids 70(4):441, 2012). Using the difference between reconstructed and referenced bubble shapes, the accuracy of the proposed algorithm was estimated. At the next step, the algorithm was applied to void fraction measurements performed in Ylönen (High-resolution flow structure measurements in a rod bundle (Diss., Eidgenössische Technische Hochschule ETH Zürich, Nr. 20961, 2013) by means of wire-mesh sensors in a rod bundle geometry. The reconstructed bubble shape yields bubble surface area and volume, hence its Sauter diameter d_{32} as well. Sauter diameter is proved to be more suitable for bubbles size characterization compared to volumetric diameter d_{30}, proved capable to capture the bi-disperse bubble size distribution in the flow. The effect of a spacer grid was studied as well: For the given spacer grid and considered flow rates, bubble size frequency distribution is obtained almost at the same position for all cases, approximately at d_{32} = 3.5 mm. This finding can be related to the specific geometry of the spacer grid or the air injection device applied in the experiments, or even to more fundamental properties of the bubble breakup and coagulation processes. In addition, an application of the new algorithm for reconstruction of a large air-water interface in a tube bundle is

  4. Reconstruction method for curvilinear structures from two views

    NASA Astrophysics Data System (ADS)

    Hoffmann, Matthias; Brost, Alexander; Jakob, Carolin; Koch, Martin; Bourier, Felix; Kurzidim, Klaus; Hornegger, Joachim; Strobel, Norbert

    2013-03-01

    Minimally invasive interventions often involve tools of curvilinear shape like catheters and guide-wires. If the camera parameters of a fluoroscopic system or a stereoscopic endoscope are known, a 3-D reconstruction of corresponding points can be computed by triangulation. Manual identification of point correspondences is time consuming, but there exist methods that automatically select corresponding points along curvilinear structures. The focus here is on the evaluation of a recent published method for catheter reconstruction from two views. A previous evaluation of this method using clinical data yielded promising results. For that evaluation, however, no 3-D ground truth data was available such that the error could only be estimated using the forward-projection of the reconstruction. In this paper, we present a more extensive evaluation of this method based on both clinical and phantom data. For the evaluation using clinical images, 36 data sets and two different catheters were available. The mean error found when reconstructing both catheters was 0.1mm +/- 0.1mm. To evaluate the error in 3-D, images of a phantom were acquired from 13 different angulations. For the phantom, A 3D C-arm CT voxel data set of the phantom was also available. A reconstruction error was calculated by comparing the triangulated 3D reconstruction result to the 3D voxel data set. The evaluation yielded an average error of 1.2mm +/- 1.2mm for the circumferential mapping catheter and 1.3mm +/- 1.0mm for the ablation catheter.

  5. Method for 3D fibre reconstruction on a microrobotic platform.

    PubMed

    Hirvonen, J; Myllys, M; Kallio, P

    2016-07-01

    Automated handling of a natural fibrous object requires a method for acquiring the three-dimensional geometry of the object, because its dimensions cannot be known beforehand. This paper presents a method for calculating the three-dimensional reconstruction of a paper fibre on a microrobotic platform that contains two microscope cameras. The method is based on detecting curvature changes in the fibre centreline, and using them as the corresponding points between the different views of the images. We test the developed method with four fibre samples and compare the results with the references measured with an X-ray microtomography device. We rotate the samples through 16 different orientations on the platform and calculate the three-dimensional reconstruction to test the repeatability of the algorithm and its sensitivity to the orientation of the sample. We also test the noise sensitivity of the algorithm, and record the mismatch rate of the correspondences provided. We use the iterative closest point algorithm to align the measured three-dimensional reconstructions with the references. The average point-to-point distances between the reconstructed fibre centrelines and the references are 20-30 μm, and the mismatch rate is low. Given the manipulation tolerance, this shows that the method is well suited to automated fibre grasping. This has also been demonstrated with actual grasping experiments. PMID:26695385

  6. Limited Angle Reconstruction Method for Reconstructing Terrestrial Plasmaspheric Densities from EUV Images

    NASA Technical Reports Server (NTRS)

    Newman, Timothy; Santhanam, Naveen; Zhang, Huijuan; Gallagher, Dennis

    2003-01-01

    A new method for reconstructing the global 3D distribution of plasma densities in the plasmasphere from a limited number of 2D views is presented. The method is aimed at using data from the Extreme Ultra Violet (EUV) sensor on NASA s Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) satellite. Physical properties of the plasmasphere are exploited by the method to reduce the level of inaccuracy imposed by the limited number of views. The utility of the method is demonstrated on synthetic data.

  7. Knee Contact Force Asymmetries in Patients Who Failed Return-to-Sport Readiness Criteria 6 Months After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Gardinier, Emily S.; Di Stasi, Stephanie; Manal, Kurt; Buchanan, Thomas S.; Snyder-Mackler, Lynn

    2015-01-01

    Background After anterior cruciate ligament (ACL) injury, contact forces are decreased in the injured knee when compared with the uninjured knee. The persistence of contact force asymmetries after ACL reconstruction may increase the risk of reinjury and may play an important role in the development of knee osteoarthritis in these patients. Functional performance may also be useful in identifying patients who demonstrate potentially harmful joint contact force asymmetries after ACL reconstruction. Hypothesis Knee joint contact force asymmetries would be present during gait after ACL reconstruction, and performance on a specific set of validated return-to-sport (RTS) readiness criteria would discriminate between those who demonstrated contact force asymmetries and those who did not. Study Design Descriptive laboratory study. Methods A total of 29 patients with ACL ruptures participated in gait analysis and RTS readiness testing 6 months after reconstruction. Muscle and joint contact forces were estimated using an electromyography (EMG)–driven musculoskeletal model of the knee. The magnitude of typical limb asymmetry in uninjured controls was used to define limits of meaningful limb asymmetry in patients after ACL reconstruction. The RTS testing included isometric quadriceps strength testing, 4 unilateral hop tests, and 2 self-report questionnaires. Paired t tests were used to assess limb symmetry for peak medial and tibiofemoral contact forces in all patients, and a mixed-design analysis of variance was used to analyze the effect of passing or failing RTS testing on contact force asymmetry. Results Among all patients, neither statistically significant nor meaningful contact force asymmetries were identified. However, patients who failed RTS testing exhibited meaningful contact force asymmetries, with tibiofemoral contact force being significantly lower for the involved knee. Conversely, patients who passed RTS testing exhibited neither significant nor meaningful

  8. Robust Methods for Sensing and Reconstructing Sparse Signals

    ERIC Educational Resources Information Center

    Carrillo, Rafael E.

    2012-01-01

    Compressed sensing (CS) is an emerging signal acquisition framework that goes against the traditional Nyquist sampling paradigm. CS demonstrates that a sparse, or compressible, signal can be acquired using a low rate acquisition process. Since noise is always present in practical data acquisition systems, sensing and reconstruction methods are…

  9. Method for image reconstruction of moving radionuclide source distribution

    DOEpatents

    Stolin, Alexander V.; McKisson, John E.; Lee, Seung Joon; Smith, Mark Frederick

    2012-12-18

    A method for image reconstruction of moving radionuclide distributions. Its particular embodiment is for single photon emission computed tomography (SPECT) imaging of awake animals, though its techniques are general enough to be applied to other moving radionuclide distributions as well. The invention eliminates motion and blurring artifacts for image reconstructions of moving source distributions. This opens new avenues in the area of small animal brain imaging with radiotracers, which can now be performed without the perturbing influences of anesthesia or physical restraint on the biological system.

  10. Method for reconstructing the history of pollution emissions

    SciTech Connect

    Not Available

    1986-05-01

    This paper examines the methods for reconstructing the history of pollution emissions. Since very few direct measurements were made in the past, documentary evidence of releases is drawn mainly from the records of economic activity. The available data are integrated into a routing network for the flow of each pollutant, from raw materials through processing, shipment of products, consumption, and finally to waste disposal. This process, called the mass balance approach, is much like reconstructing a fossil skeleton. It was the process was used in the pilot historical study of the pollution of the Hudson region.

  11. Evolutionary method for predicting surface reconstructions with variable stoichiometry

    NASA Astrophysics Data System (ADS)

    Zhu, Qiang; Li, Li; Oganov, Artem R.; Allen, Philip B.

    2013-05-01

    We present a specially designed evolutionary algorithm for the prediction of surface reconstructions. This technique allows one to automatically explore stable and low-energy metastable configurations with variable surface atoms and variable surface unit cells through the whole chemical potential range. The power of evolutionary search is demonstrated by the efficient identification of diamond 2×1 (100) and 2×1 (111) surface reconstructions with a fixed number of surface atoms and a fixed cell size. With further variation of surface unit cells, we study the reconstructions of the polar surface MgO (111). Experiment has detected an oxygen trimer (ozone) motif [Plass , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.81.4891 81, 4891 (1998)]. We predict another version of this motif which can be thermodynamically stable in extreme oxygen-rich conditions. Finally, we perform a variable stoichiometry search for a complex ternary system: semipolar GaN (101¯1) with and without adsorbed oxygen. The search yields a counterintuitive reconstruction based on N3 trimers. These examples demonstrate that an automated scheme to explore the energy landscape of surfaces will improve our understanding of surface reconstructions. The method presented in this paper can be generally applied to binary and multicomponent systems.

  12. Operative and nonoperative treatment options for ACL tears in the adult patient: a conceptual review.

    PubMed

    Bogunovic, Ljiljana; Matava, Matthew J

    2013-11-01

    Injury to the anterior cruciate ligament (ACL) is common among athletic individuals. Both nonoperative and operative treatment options exist. The optimal treatment of an adult with an ACL tear depends on several patient-specific factors, including age, occupation, and desired activity level. In less active patients with sedentary jobs, nonoperative management, consisting of physical therapy, bracing, and activity modification can yield successful results. In active patients who want to resume participation in jumping, cutting, or pivoting sports, patients who have physically demanding occupations, or patients who fail a trial of nonoperative management, ACL reconstruction is recommended. Reconstruction utilizing autograft tissue is preferred over allograft, especially in the younger athlete, but allograft tissue is a reasonable option in the older (aged > 40 years) and less active adult, as well. Successful results have been achieved with both patellar tendon and hamstring grafts. The optimal treatment in adult patients with ACL tears should be based on careful consideration of the patient's goals for return to activity, knee-specific comorbidities, such as coexistent meniscal pathology or osteoarthritis, and his or her willingness to follow a detailed rehabilitation regimen. Our article provides an overview of current nonoperative and operative treatment options for adults with ACL tears, considers the outcomes of both nonoperative and operative strategies, and provides general recommendations as to the ideal management for a given patient. PMID:24231595

  13. A Comparative Animal Study of Tendon Grafts Healing After Remnant-Preserving Versus Conventional Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Zhang, Lei; Jiang, Kan; Chai, Hao; Zhou, Mei; Bai, Jingping

    2016-01-01

    Background The aim of this study was to determine if anterior cruciate ligament (ACL) reconstruction by remnant preservation promotes cell proliferation, vascularization, proprioception recovery, and improved biomechanical properties of the tendon grafts. Material/Methods 75 New Zealand rabbits were randomly assigned into the control group (group A), conventional ACL reconstruction group (group B), ACL reconstruction using remnant preservation and graft through remnant sleeve technique group (group C), and ACL reconstruction using remnant preservation and remnant tensioning technique group (group D). The remnant and healing of tendon grafts in groups C and D were observed at 3, 6, and 12 weeks after surgery, and the mRNA expression levels of VEGF, NT-3 and GAP-43 in ACL (group A) or tendon graft samples (groups B, C, and D) were determined by real-time PCR. Tendon graft cell count, microvessel density (MVD), and proprioceptors were determined by H&E staining, CD34, and S-100 immunohistochemical staining. The biomechanical properties of the tendon graft at week 12 in groups B, C, and D were examined by using a tensile strength test. Results Remnant and tendon grafts were not healed at 3, 6, and 12 weeks after the operation in groups C and D. VEGF, NT-3, and GAP-43 mRNA expressions in groups B, C, and D were higher than those in group A (P<0.05), but no significant difference was observed between groups B, C, and D (P>0.05). Furthermore, tendon graft cell count, MVD, proprioception, and biomechanical properties showed no significant differences (P>0.05) among groups B, C, and D at various time points. Conclusions There was no significant difference in cell proliferation, vascularization, proprioception recovery, or biomechanical properties of the tendon grafts between remnant-preserving and conventional ACL reconstruction methods. PMID:27669454

  14. A new method of morphological comparison for bony reconstructive surgery: maxillary reconstruction using scapular tip bone

    NASA Astrophysics Data System (ADS)

    Chan, Harley; Gilbert, Ralph W.; Pagedar, Nitin A.; Daly, Michael J.; Irish, Jonathan C.; Siewerdsen, Jeffrey H.

    2010-02-01

    esthetic appearance is one of the most important factors for reconstructive surgery. The current practice of maxillary reconstruction chooses radial forearm, fibula or iliac rest osteocutaneous to recreate three-dimensional complex structures of the palate and maxilla. However, these bone flaps lack shape similarity to the palate and result in a less satisfactory esthetic. Considering similarity factors and vasculature advantages, reconstructive surgeons recently explored the use of scapular tip myo-osseous free flaps to restore the excised site. We have developed a new method that quantitatively evaluates the morphological similarity of the scapula tip bone and palate based on a diagnostic volumetric computed tomography (CT) image. This quantitative result was further interpreted as a color map that rendered on the surface of a three-dimensional computer model. For surgical planning, this color interpretation could potentially assist the surgeon to maximize the orientation of the bone flaps for best fit of the reconstruction site. With approval from the Research Ethics Board (REB) of the University Health Network, we conducted a retrospective analysis with CT image obtained from 10 patients. Each patient had a CT scans including the maxilla and chest on the same day. Based on this image set, we simulated total, subtotal and hemi palate reconstruction. The procedure of simulation included volume segmentation, conversing the segmented volume to a stereo lithography (STL) model, manual registration, computation of minimum geometric distances and curvature between STL model. Across the 10 patients data, we found the overall root-mean-square (RMS) conformance was 3.71+/- 0.16 mm

  15. Rotational and translational laxity after computer-navigated single- and double-bundle anterior cruciate ligament reconstruction.

    PubMed

    Hofbauer, M; Valentin, P; Kdolsky, R; Ostermann, R C; Graf, A; Figl, M; Aldrian, S

    2010-09-01

    Based on biomechanical cadaver studies, anatomic double-bundle reconstruction of the anterior cruciate ligament (ACL) was introduced to achieve better stability in the knee, particularly in respect of rotatory loads. Previously, the success of ACL reconstruction was believed to be mainly dependent on correct positioning of the graft, irrespective of the number of reconstructed bundles for which computer-assisted surgery was developed to avoid malpositioning of the tunnel. The aim of the present study is to compare rotational and translational stability after computer-navigated standard single-bundle, and anatomic double-bundle ACL reconstruction. The authors investigated 55 consecutive patients who had undergone the single-bundle or double-bundle ACL reconstruction procedure with the use of autogenous hamstring tendon grafts and EndoButton fixation, and the patients had been followed for a minimum period of 24 months. Intraoperative, anteroposterior and rotational laxity was measured with the computer navigation system, and compared between groups. Both surgical procedures significantly reduced anteroposterior displacement (AP) and internal rotation (IR) of the tibia compared to the pre-operative ACL-deficient knee (P < 0.05). No significant differences were registered between groups with regard to anteroposterior displacement of the tibia. A significantly greater reduction in internal rotation was noted in the double-bundle group (15.6 degrees) compared to the single-bundle group (7.1 degrees). The IKDC and Lysholm score were significantly higher in the double-bundle group. However, the results were excellent in both groups. The use of a computer-assisted ACL reconstruction, which is a highly accurate method of graft placement, could be useful for inexperienced surgeons to avoid malposition. Whether double-bundle ACL reconstruction, which was associated with improved rotational laxity and significantly better IKDC and Lysholm scores compared to the standard single

  16. Human knee laxity in ACL-deficient and physiological contralateral joints: intra-operative measurements using a navigation system

    PubMed Central

    2014-01-01

    Background The comprehension of human knee laxity and of the failures of relevant surgical reconstructions of the anterior cruciate ligament (ACL) can be enhanced by the knowledge of the laximetric status of the contralateral healthy knee (CHK). Rarely this is available in patients, directly from the skeletal structures, and for a number of the standard clinical tests. The general aim of this study was to measure the extent to which laxity occurs immediately before surgery in the ACL deficient knee (ADK) with respect to CHK, in a number of standard clinical evaluation tests. Method Thirty-two patients with ACL deficiency were analyzed at ADK and at CHK by a navigation system immediately before reconstructions. Knee laxity was assessed based on digitized anatomical references during the antero-posterior drawer, Lachman, internal-external rotation, varus-valgus, and pivot-shift tests. Antero-posterior laxity was normalized based on patient-specific length of the tibial plateau. Results In the drawer test, statistical significance (p < 0.05) was found for the larger antero-posterior laxity in ADK than in CHK, on average, of 54' in the medial and 47' in the lateral compartments, when measured in normalized translations. In the Lachman test, these were about 106' and 68'. The pivot-shift test revealed a significant 70' larger antero-posterior central laxity and a 32' larger rotational laxity. No statistically relevant differences were observed in the other tests. Conclusion The first conclusion is that it is important to measure also the antero-posterior and rotational laxity of the uninjured contralateral knee in assessing the laxity of the injured knee. A second is that the Lachman test shows knee laxity better than the AP drawer, and that the pivot-shift test was the only one able to reveal rotational instability. The present original measurements and analyses contribute to the knowledge of knee joint mechanics, with possible relevant applications in biomedical

  17. Injury patterns in patients presenting with a recurrent anterior cruciate ligament tear following primary reconstruction

    PubMed Central

    Sayampanathan, Andrew A.; Bin Abd Razak, Hamid Rahmatullah; Chong, Hwei Chi; Tan, Hwee-Chye Andrew

    2016-01-01

    Background An anterior cruciate ligament (ACL) graft rupture or a primary ACL injury in the contralateral knee is one of the greatest concerns of patients following primary anterior cruciate ligament reconstruction (ACLR). Our study describes the epidemiology and presence of concomitant meniscal injuries of patients with a graft rupture following primary ACLR or a primary rupture of the contralateral ACL following primary ACLR of the ipsilateral knee. Methods We reviewed the medical records of 42 patients who underwent a second ACLR. ACLR was performed using the ipsilateral semitendinosus and gracilis autograft. Variables extracted included the presence of concomitant MM and LM injuries intra-operatively, the patients’ level of intensity of sport (light, moderate, strenuous), duration of rehabilitation and mechanism of injury (contact, non-contact). Results Twenty-four (57.1%) patients had graft rupture of a previously reconstructed ACL of which 20 (83.3%) were male and 18 (42.9%) patients had a primary ACL tear of the contralateral knee following ACLR of the ipsilateral knee of which 18 (100%) were male. Patient who sustained a graft rupture were younger (29.5 vs. 31.9 years), had a higher body mass index (BMI) (26.42 vs. 25.10 kg/m2) and had a longer time before re-injury (6.18 vs. 4.94 years). Concomitant meniscal injury rates were comparable in both groups and the medial meniscus was injured more often. Conclusions This study describes the demographics of 2nd ACL injuries in the Asian population. Additional studies that investigate the differences in knee anatomy of Asians and Caucasians and their impact on ACL injuries should be performed. PMID:27429958

  18. Anatomical Single-bundle Anterior Cruciate Ligament Reconstruction Using a Freehand Transtibial Technique

    PubMed Central

    Nha, Kyung-Wook; Han, Jae-Hwi; Kwon, Jae-Ho; Kang, Kyung-Woon; Park, Hyung-Joon

    2015-01-01

    Purpose In anatomical single-bundle (SB) anterior cruciate ligament (ACL) reconstruction, the traditional transtibial approach can limit anatomical placement of the femoral tunnel. Surgical Technique We present a novel three-point freehand technique that allows for anatomic SB ACL reconstruction with the transtibial technique. Materials and Methods Between January 2012 and December 2012, 55 ACL reconstructions were performed using the three-point freehand technique. All the patients were followed for a minimum of 12 months post-operatively. Clinical evaluation was done using the Lysholm score and International Knee Documentation Committee (IKDC) grade. All patients were analyzed by 3-dimensional computed tomography (3D CT) at 1 week after surgery. Results The mean Lysholm score improved from 68.2±12.7 points preoperatively to 89.2±8.2 points at final follow-up. At final follow-up, the IKDC grade was normal in 42 patients and nearly normal in 13 patients. None of the patients had a positive pivot shift test, anterior drawer test and Lachman test at final follow-up. The anatomical position of the femoral tunnel was confirmed on 3D CT scans. Conclusions The three-point freehand technique for SB transtibial ACL reconstruction is a simple, anatomic technique showing good clinical results. PMID:26060611

  19. Improving automated 3D reconstruction methods via vision metrology

    NASA Astrophysics Data System (ADS)

    Toschi, Isabella; Nocerino, Erica; Hess, Mona; Menna, Fabio; Sargeant, Ben; MacDonald, Lindsay; Remondino, Fabio; Robson, Stuart

    2015-05-01

    This paper aims to provide a procedure for improving automated 3D reconstruction methods via vision metrology. The 3D reconstruction problem is generally addressed using two different approaches. On the one hand, vision metrology (VM) systems try to accurately derive 3D coordinates of few sparse object points for industrial measurement and inspection applications; on the other, recent dense image matching (DIM) algorithms are designed to produce dense point clouds for surface representations and analyses. This paper strives to demonstrate a step towards narrowing the gap between traditional VM and DIM approaches. Efforts are therefore intended to (i) test the metric performance of the automated photogrammetric 3D reconstruction procedure, (ii) enhance the accuracy of the final results and (iii) obtain statistical indicators of the quality achieved in the orientation step. VM tools are exploited to integrate their main functionalities (centroid measurement, photogrammetric network adjustment, precision assessment, etc.) into the pipeline of 3D dense reconstruction. Finally, geometric analyses and accuracy evaluations are performed on the raw output of the matching (i.e. the point clouds) by adopting a metrological approach. The latter is based on the use of known geometric shapes and quality parameters derived from VDI/VDE guidelines. Tests are carried out by imaging the calibrated Portable Metric Test Object, designed and built at University College London (UCL), UK. It allows assessment of the performance of the image orientation and matching procedures within a typical industrial scenario, characterised by poor texture and known 3D/2D shapes.

  20. Anterolateral Extra-articular Soft Tissue Reconstruction in Anterolateral Rotatory Instability of the Knee.

    PubMed

    Kernkamp, Willem A; van de Velde, Samuel K; Bakker, Eric W P; van Arkel, Ewoud R A

    2015-12-01

    Anterolateral rotatory instability (ALRI) occurs after injury to the anterior cruciate ligament (ACL) and the anterolateral structures of the knee. We present a technique for anterolateral extra-articular soft-tissue (ALES) reconstruction of the knee that can be used in revision ACL reconstruction cases, cases of persistent ALRI after adequate ACL reconstruction, and cases with severe ALRI after primary ACL rupture. The surgeon performs ALES reconstruction with a strip of iliotibial tract autograft while respecting the anatomic origin and insertion of the anterolateral ligament. The purpose of this reconstruction is to restore the normal anterolateral rotatory stability of the knee in ALES-deficient patients. PMID:27284525

  1. Runx2-Modified Adipose-Derived Stem Cells Promote Tendon Graft Integration in Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Zhang, Xin; Ma, Yong; Fu, Xin; Liu, Qiang; Shao, Zhenxing; Dai, Linghui; Pi, Yanbin; Hu, Xiaoqing; Zhang, Jiying; Duan, Xiaoning; Chen, Wenqing; Chen, Ping; Zhou, Chunyan; Ao, Yingfang

    2016-01-01

    Runx2 is a powerful osteo-inductive factor and adipose-derived stem cells (ADSCs) are multipotent. However, it is unknown whether Runx2-overexpressing ADSCs (Runx2-ADSCs) could promote anterior cruciate ligament (ACL) reconstruction. We evaluated the effect of Runx2-ADSCs on ACL reconstruction in vitro and in vivo. mRNA expressions of osteocalcin (OCN), bone sialoprotein (BSP) and collagen I (COLI) increased over time in Runx2-ADSCs. Runx2 overexpression inhibited LPL and PPARγ mRNA expressions. Runx2 induced alkaline phosphatase activity markedly. In nude mice injected with Runx2-ADSCs, promoted bone formation was detected by X-rays 8 weeks after injection. The healing of tendon-to-bone in a rabbit model of ACL reconstruction treated with Runx2-ADSCs, fibrin glue only and an RNAi targeting Runx2, was evaluated with CT 3D reconstruction, histological analysis and biomechanical methods. CT showed a greater degree of new bone formation around the bone tunnel in the group treated with Runx2-ADSCs compared with the fibrin glue group and RNAi Runx2 group. Histology showed that treatment with Runx2-ADSCs led to a rapid and significant increase at the tendon-to-bone compared with the control groups. Biomechanical tests demonstrated higher tendon pullout strength in the Runx2-ADSCs group at early time points. The healing of the attachment in ACL reconstruction was enhanced by Runx2-ADSCs. PMID:26743583

  2. Optical Sensors and Methods for Underwater 3D Reconstruction

    PubMed Central

    Massot-Campos, Miquel; Oliver-Codina, Gabriel

    2015-01-01

    This paper presents a survey on optical sensors and methods for 3D reconstruction in underwater environments. The techniques to obtain range data have been listed and explained, together with the different sensor hardware that makes them possible. The literature has been reviewed, and a classification has been proposed for the existing solutions. New developments, commercial solutions and previous reviews in this topic have also been gathered and considered. PMID:26694389

  3. Pseudocyclops: two cases of ACL graft partial tears mimicking cyclops lesions on MRI.

    PubMed

    Simpfendorfer, Claus; Miniaci, Anthony; Subhas, Naveen; Winalski, Carl S; Ilaslan, Hakan

    2015-08-01

    Arthroscopic reconstruction of the anterior cruciate ligament (ACL) using autografts or allografts is a common surgical procedure, particularly in young athletes. Although the procedure has excellent success rates, complications such as mechanical impingement, graft rupture, and arthrofibrosis can occur, often necessitating additional surgery. Magnetic resonance (MR) imaging has become a valuable tool in evaluating complications after ACL reconstruction. We report two cases of ACL reconstruction complicated by arthroscopically proven partial graft tears. In both cases the torn anterior graft fibers were flipped into the intercondylar notch, mimicking anterior arthrofibrosis, i.e., a "cyclops lesion," on MR imaging. Careful review of the direction of graft fibers on MR imaging in the "pseudocyclops" lesions can help differentiate these partial tears from the fibrosis of a true cyclops. The "pseudocyclops" lesion is a previously undescribed MR imaging sign of partial ACL graft tear. Larger studies are required to determine the sensitivity and specificity of the sign, as well as the clinical importance of these partial graft tears. PMID:25620690

  4. Computational methods estimating uncertainties for profile reconstruction in scatterometry

    NASA Astrophysics Data System (ADS)

    Gross, H.; Rathsfeld, A.; Scholze, F.; Model, R.; Bär, M.

    2008-04-01

    The solution of the inverse problem in scatterometry, i.e. the determination of periodic surface structures from light diffraction patterns, is incomplete without knowledge of the uncertainties associated with the reconstructed surface parameters. With decreasing feature sizes of lithography masks, increasing demands on metrology techniques arise. Scatterometry as a non-imaging indirect optical method is applied to periodic line-space structures in order to determine geometric parameters like side-wall angles, heights, top and bottom widths and to evaluate the quality of the manufacturing process. The numerical simulation of the diffraction process is based on the finite element solution of the Helmholtz equation. The inverse problem seeks to reconstruct the grating geometry from measured diffraction patterns. Restricting the class of gratings and the set of measurements, this inverse problem can be reformulated as a non-linear operator equation in Euclidean spaces. The operator maps the grating parameters to the efficiencies of diffracted plane wave modes. We employ a Gauss-Newton type iterative method to solve this operator equation and end up minimizing the deviation of the measured efficiency or phase shift values from the simulated ones. The reconstruction properties and the convergence of the algorithm, however, is controlled by the local conditioning of the non-linear mapping and the uncertainties of the measured efficiencies or phase shifts. In particular, the uncertainties of the reconstructed geometric parameters essentially depend on the uncertainties of the input data and can be estimated by various methods. We compare the results obtained from a Monte Carlo procedure to the estimations gained from the approximative covariance matrix of the profile parameters close to the optimal solution and apply them to EUV masks illuminated by plane waves with wavelengths in the range of 13 nm.

  5. Anterior cruciate ligament tears: reconstruction and rehabilitation.

    PubMed

    Smith, Mary Atkinson; Smith, W Todd; Kosko, Paul

    2014-01-01

    Tears of the anterior cruciate ligament (ACL) are common knee injuries experienced by athletes and people with active lifestyles. It is important for members of the healthcare team to take an evidence-based approach to the diagnosis, surgical management, and postoperative rehabilitation of patients with an ACL-deficient knee. Mechanism of ACL injury and diagnostic testing is consistent throughout the literature. Patients frequently opt for ACL reconstruction, and many surgical techniques for ACL reconstruction are available with no clear consensus regarding superiority. Surgeon preference dictates the type of reconstruction and graft choice utilized. No standardized pre- and postoperative rehabilitation protocol exists. However, rehabilitation plays an important role in functional outcomes. A comprehensive rehabilitation program is needed pre- and postoperatively to produce positive patient outcomes.

  6. Two-Stage Revision Anterior Cruciate Ligament Reconstruction: Bone Grafting Technique Using an Allograft Bone Matrix.

    PubMed

    Chahla, Jorge; Dean, Chase S; Cram, Tyler R; Civitarese, David; O'Brien, Luke; Moulton, Samuel G; LaPrade, Robert F

    2016-02-01

    Outcomes of primary anterior cruciate ligament (ACL) reconstruction have been reported to be far superior to those of revision reconstruction. However, as the incidence of ACL reconstruction is rapidly increasing, so is the number of failures. The subsequent need for revision ACL reconstruction is estimated to occur in up to 13,000 patients each year in the United States. Revision ACL reconstruction can be performed in one or two stages. A two-stage approach is recommended in cases of improper placement of the original tunnels or in cases of unacceptable tunnel enlargement. The aim of this study was to describe the technique for allograft ACL tunnel bone grafting in patients requiring a two-stage revision ACL reconstruction. PMID:27274452

  7. Two-Stage Revision Anterior Cruciate Ligament Reconstruction: Bone Grafting Technique Using an Allograft Bone Matrix.

    PubMed

    Chahla, Jorge; Dean, Chase S; Cram, Tyler R; Civitarese, David; O'Brien, Luke; Moulton, Samuel G; LaPrade, Robert F

    2016-02-01

    Outcomes of primary anterior cruciate ligament (ACL) reconstruction have been reported to be far superior to those of revision reconstruction. However, as the incidence of ACL reconstruction is rapidly increasing, so is the number of failures. The subsequent need for revision ACL reconstruction is estimated to occur in up to 13,000 patients each year in the United States. Revision ACL reconstruction can be performed in one or two stages. A two-stage approach is recommended in cases of improper placement of the original tunnels or in cases of unacceptable tunnel enlargement. The aim of this study was to describe the technique for allograft ACL tunnel bone grafting in patients requiring a two-stage revision ACL reconstruction.

  8. Patient Outcomes and Predictors of Success After Revision Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Johnson, William R.; Makani, Amun; Wall, Andrew J.; Hosseini, Ali; Hampilos, Perry; Li, Guoan; Gill, Thomas J.

    2015-01-01

    Background: Patient outcomes and predictors of success after revision anterior cruciate ligament (ACL) reconstruction are currently limited in the literature. Existing studies either have a small study size or are difficult to interpret because of the multiple surgeons involved in the care of the study sample. Purpose: To determine patient outcomes and predictors of success or failure after a single-stage revision ACL reconstruction by a single fellowship-trained senior surgeon at a single institution. Study Design: Case series; Level of evidence, 4. Methods: A total of 78 patients who underwent revision ACL reconstruction by a single surgeon from 2010 to 2014 were contacted and available for follow-up. The mean time from revision procedure to follow-up was 52 months. Those patients who were able to participate in the study sent in a completed Tegner activity level scale, International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, and IKDC Current Health Assessment Form. The patients’ medical records were also thoroughly reviewed. Results: Five patients had subsequent failure after revision surgery. The median Tegner score was 6 at follow-up, and the mean subjective IKDC score was 72.5. There was no statistically significant difference in outcome scores when comparing revision graft type, body mass index, sex, need for bone grafting, and time from failure to revision. Patients with failures after primary ACL reconstruction secondary to a traumatic event were found to have statistically significantly higher IKDC scores (mean, 76.6) after revision when compared with nontraumatic failures (mean, 67.1), even when controlling for confounders (P < .017). Conclusion: Revision ACL reconstruction is effective in improving patient activity levels and satisfaction. However, the subjective IKDC results are quite variable and likely based on multiple factors. Patients with traumatic injuries contributing to graft failure after primary ACL reconstruction

  9. Harmonizing multiple methods for reconstructing historical potential and reference evapotranspiration

    USGS Publications Warehouse

    Belaineh, Getachew; Sumner, David; Carter, Edward; Clapp, David

    2013-01-01

    Potential evapotranspiration (PET) and reference evapotranspiration (RET) data are usually critical components of hydrologic analysis. Many different equations are available to estimate PET and RET. Most of these equations, such as the Priestley-Taylor and Penman- Monteith methods, rely on detailed meteorological data collected at ground-based weather stations. Few weather stations collect enough data to estimate PET or RET using one of the more complex evapotranspiration equations. Currently, satellite data integrated with ground meteorological data are used with one of these evapotranspiration equations to accurately estimate PET and RET. However, earlier than the last few decades, historical reconstructions of PET and RET needed for many hydrologic analyses are limited by the paucity of satellite data and of some types of ground data. Air temperature stands out as the most generally available meteorological ground data type over the last century. Temperature-based approaches used with readily available historical temperature data offer the potential for long period-of-record PET and RET historical reconstructions. A challenge is the inconsistency between the more accurate, but more data intensive, methods appropriate for more recent periods and the less accurate, but less data intensive, methods appropriate to the more distant past. In this study, multiple methods are harmonized in a seamless reconstruction of historical PET and RET by quantifying and eliminating the biases of the simple Hargreaves-Samani method relative to the more complex and accurate Priestley-Taylor and Penman-Monteith methods. This harmonization process is used to generate long-term, internally consistent, spatiotemporal databases of PET and RET.

  10. Allograft safety in anterior cruciate ligament reconstruction.

    PubMed

    Cohen, Steven B; Sekiya, Jon K

    2007-10-01

    Allograft tissue seems to provide an excellent option for reconstruction of the ACL in the primary and revision setting. Although in general the risks of using allograft tissue in ACL reconstruction are low, the consequences of complications associated with disease or infection transmission or of recurrent instability secondary to graft failure are large. Surgeons should provide patients with the information available regarding allograft risks and should have thorough knowledge of the source and preparation of the grafts by their tissue bank before implantation for ACL reconstruction.

  11. Allograft safety in anterior cruciate ligament reconstruction.

    PubMed

    Cohen, Steven B; Sekiya, Jon K

    2007-10-01

    Allograft tissue seems to provide an excellent option for reconstruction of the ACL in the primary and revision setting. Although in general the risks of using allograft tissue in ACL reconstruction are low, the consequences of complications associated with disease or infection transmission or of recurrent instability secondary to graft failure are large. Surgeons should provide patients with the information available regarding allograft risks and should have thorough knowledge of the source and preparation of the grafts by their tissue bank before implantation for ACL reconstruction. PMID:17920955

  12. All-inside anterior cruciate ligament reconstruction.

    PubMed

    Blackman, Andrew J; Stuart, Michael J

    2014-10-01

    All-inside anterior cruciate ligament (ACL) reconstruction has undergone a series of modifications over the past 20 years. Current techniques offer the advantages of improved cosmesis, less postoperative pain, decreased bone removal, and gracilis preservation. Few all-inside ACL reconstruction outcome studies are available; therefore, additional research is necessary to compare the results to conventional techniques. The purpose of this article is to review the evolution of all-inside ACL reconstruction, the advantages and disadvantages, our preferred technique, and clinical experience to date.

  13. Gene Expression Network Reconstruction by LEP Method Using Microarray Data

    PubMed Central

    You, Na; Mou, Peng; Qiu, Ting; Kou, Qiang; Zhu, Huaijin; Chen, Yuexi; Wang, Xueqin

    2012-01-01

    Gene expression network reconstruction using microarray data is widely studied aiming to investigate the behavior of a gene cluster simultaneously. Under the Gaussian assumption, the conditional dependence between genes in the network is fully described by the partial correlation coefficient matrix. Due to the high dimensionality and sparsity, we utilize the LEP method to estimate it in this paper. Compared to the existing methods, the LEP reaches the highest PPV with the sensitivity controlled at the satisfactory level. A set of gene expression data from the HapMap project is analyzed for illustration. PMID:23365528

  14. Reconstruction of Banknote Fragments Based on Keypoint Matching Method.

    PubMed

    Gwo, Chih-Ying; Wei, Chia-Hung; Li, Yue; Chiu, Nan-Hsing

    2015-07-01

    Banknotes may be shredded by a scrap machine, ripped up by hand, or damaged in accidents. This study proposes an image registration method for reconstruction of multiple sheets of banknotes. The proposed method first constructs different scale spaces to identify keypoints in the underlying banknote fragments. Next, the features of those keypoints are extracted to represent their local patterns around keypoints. Then, similarity is computed to find the keypoint pairs between the fragment and the reference banknote. The banknote fragments can determine the coordinate and amend the orientation. Finally, an assembly strategy is proposed to piece multiple sheets of banknote fragments together. Experimental results show that the proposed method causes, on average, a deviation of 0.12457 ± 0.12810° for each fragment while the SIFT method deviates 1.16893 ± 2.35254° on average. The proposed method not only reconstructs the banknotes but also decreases the computing cost. Furthermore, the proposed method can estimate relatively precisely the orientation of the banknote fragments to assemble.

  15. Acellular Dermal Matrix as a Core Strut for Projection in Nipple Reconstruction: Approaches for Three Different Methods of Breast Reconstruction

    PubMed Central

    Park, Gui-Yong; Cho, Hee-Eun; Lee, Byung-Il; Park, Seung-Ha

    2016-01-01

    Background The objective of this paper was to describe a novel technique for improving the maintenance of nipple projection in primary nipple reconstruction by using acellular dermal matrix as a strut in one of three different configurations, according to the method of prior breast reconstruction. The struts were designed to best fill the different types of dead spaces in nipple reconstruction depending on the breast reconstruction method. Methods A total of 50 primary nipple reconstructions were performed between May 2012 and May 2015. The prior breast reconstruction methods were latissimus dorsi (LD) flap (28 cases), transverse rectus abdominis myocutaneous (TRAM) flap (10 cases), or tissue expander/implant (12 cases). The nipple reconstruction technique involved the use of local flaps, including the C-V flap or star flap. A 1×2-cm acellular dermal matrix was placed into the core with O-, I-, and L-shaped struts for prior LD, TRAM, and expander/implant methods, respectively. The projection of the reconstructed nipple was measured at the time of surgery and at 3, 6, and 9 months postoperatively. Results The nine-month average maintenance of nipple projection was 73.0%±9.67% for the LD flap group using an O-strut, 72.0%±11.53% for the TRAM flap group using an I-strut, and 69.0%±10.82% for the tissue expander/implant group using an L-strut. There were no cases of infection, wound dehiscence, or flap necrosis. Conclusions The application of an acellular dermal matrix with a different kind of strut for each of 3 breast reconstruction methods is an effective addition to current techniques for improving the maintenance of long-term projection in primary nipple reconstruction. PMID:27689049

  16. Acellular Dermal Matrix as a Core Strut for Projection in Nipple Reconstruction: Approaches for Three Different Methods of Breast Reconstruction

    PubMed Central

    Park, Gui-Yong; Cho, Hee-Eun; Lee, Byung-Il; Park, Seung-Ha

    2016-01-01

    Background The objective of this paper was to describe a novel technique for improving the maintenance of nipple projection in primary nipple reconstruction by using acellular dermal matrix as a strut in one of three different configurations, according to the method of prior breast reconstruction. The struts were designed to best fill the different types of dead spaces in nipple reconstruction depending on the breast reconstruction method. Methods A total of 50 primary nipple reconstructions were performed between May 2012 and May 2015. The prior breast reconstruction methods were latissimus dorsi (LD) flap (28 cases), transverse rectus abdominis myocutaneous (TRAM) flap (10 cases), or tissue expander/implant (12 cases). The nipple reconstruction technique involved the use of local flaps, including the C-V flap or star flap. A 1×2-cm acellular dermal matrix was placed into the core with O-, I-, and L-shaped struts for prior LD, TRAM, and expander/implant methods, respectively. The projection of the reconstructed nipple was measured at the time of surgery and at 3, 6, and 9 months postoperatively. Results The nine-month average maintenance of nipple projection was 73.0%±9.67% for the LD flap group using an O-strut, 72.0%±11.53% for the TRAM flap group using an I-strut, and 69.0%±10.82% for the tissue expander/implant group using an L-strut. There were no cases of infection, wound dehiscence, or flap necrosis. Conclusions The application of an acellular dermal matrix with a different kind of strut for each of 3 breast reconstruction methods is an effective addition to current techniques for improving the maintenance of long-term projection in primary nipple reconstruction.

  17. Methods for reconstructing acoustic quantities based on acoustic pressure measurements.

    PubMed

    Wu, Sean F

    2008-11-01

    This paper presents an overview of the acoustic imaging methods developed over the past three decades that enable one to reconstruct all acoustic quantities based on the acoustic pressure measurements taken around a target source at close distances. One such method that has received the most attention is known as near-field acoustical holography (NAH). The original NAH relies on Fourier transforms that are suitable for a surface containing a level of constant coordinate in a source-free region. Other methods are developed to reconstruct the acoustic quantities in three-dimensional space and on an arbitrary three-dimensional source surface. Note that there is a fine difference between Fourier transform based NAH and other methods that is largely overlooked. The former can offer a wave number spectrum, thus enabling visualization of various structural waves of different wavelengths that travel on the surface of a structure; the latter cannot provide such information, which is critical to acquire an in-depth understanding of the interrelationships between structural vibrations and sound radiation. All these methods are discussed in this paper, their advantages and limitations are compared, and the need for further development to analyze the root causes of noise and vibration problems is discussed.

  18. Risk Factors for Surgical Site Infections Following Anterior Cruciate Ligament Reconstruction.

    PubMed

    Murphy, Michael V; Du, Dongyi Tony; Hua, Wei; Cortez, Karoll J; Butler, Melissa G; Davis, Robert L; DeCoster, Thomas A; Johnson, Laura; Li, Lingling; Nakasato, Cynthia; Nordin, James D; Ramesh, Mayur; Schum, Michael; Von Worley, Ann; Zinderman, Craig; Platt, Richard; Klompas, Michael

    2016-07-01

    OBJECTIVE To determine the effect of graft choice (allograft, bone-patellar tendon-bone autograft, or hamstring autograft) on deep tissue infections following anterior cruciate ligament (ACL) reconstructions. DESIGN Retrospective cohort study. SETTING AND POPULATION Patients from 6 US health plans who underwent ACL reconstruction from January 1, 2000, through December 31, 2008. METHODS We identified ACL reconstructions and potential postoperative infections using claims data. A hierarchical stratified sampling strategy was used to identify patients for medical record review to confirm ACL reconstructions and to determine allograft vs autograft tissue implanted, clinical characteristics, and infection status. We estimated infection rates overall and by graft type. We used logistic regression to assess the association between infections and patients' demographic characteristics, comorbidities, and choice of graft. RESULTS On review of 1,452 medical records, we found 55 deep wound infections. With correction for sampling weights, infection rates varied by graft type: 0.5% (95% CI, 0.3%-0.8%) with allografts, 0.6% (0.1%-1.5%) with bone-patellar tendon-bone autografts, and 2.5% (1.9%-3.1%) with hamstring autograft. After adjusting for potential confounders, we found an increased infection risk with hamstring autografts compared with allografts (odds ratio, 5.9; 95% CI, 2.8-12.8). However, there was no difference in infection risk among bone-patellar tendon-bone autografts vs allografts (odds ratio, 1.2; 95% CI, 0.3-4.8). CONCLUSIONS The overall risk for deep wound infections following ACL reconstruction is low but it does vary by graft type. Infection risk was highest in hamstring autograft recipients compared with allograft recipients and bone-patellar tendon-bone autograft recipients. Infect Control Hosp Epidemiol 2016;37:827-833.

  19. Risk Factors for Surgical Site Infections Following Anterior Cruciate Ligament Reconstruction.

    PubMed

    Murphy, Michael V; Du, Dongyi Tony; Hua, Wei; Cortez, Karoll J; Butler, Melissa G; Davis, Robert L; DeCoster, Thomas A; Johnson, Laura; Li, Lingling; Nakasato, Cynthia; Nordin, James D; Ramesh, Mayur; Schum, Michael; Von Worley, Ann; Zinderman, Craig; Platt, Richard; Klompas, Michael

    2016-07-01

    OBJECTIVE To determine the effect of graft choice (allograft, bone-patellar tendon-bone autograft, or hamstring autograft) on deep tissue infections following anterior cruciate ligament (ACL) reconstructions. DESIGN Retrospective cohort study. SETTING AND POPULATION Patients from 6 US health plans who underwent ACL reconstruction from January 1, 2000, through December 31, 2008. METHODS We identified ACL reconstructions and potential postoperative infections using claims data. A hierarchical stratified sampling strategy was used to identify patients for medical record review to confirm ACL reconstructions and to determine allograft vs autograft tissue implanted, clinical characteristics, and infection status. We estimated infection rates overall and by graft type. We used logistic regression to assess the association between infections and patients' demographic characteristics, comorbidities, and choice of graft. RESULTS On review of 1,452 medical records, we found 55 deep wound infections. With correction for sampling weights, infection rates varied by graft type: 0.5% (95% CI, 0.3%-0.8%) with allografts, 0.6% (0.1%-1.5%) with bone-patellar tendon-bone autografts, and 2.5% (1.9%-3.1%) with hamstring autograft. After adjusting for potential confounders, we found an increased infection risk with hamstring autografts compared with allografts (odds ratio, 5.9; 95% CI, 2.8-12.8). However, there was no difference in infection risk among bone-patellar tendon-bone autografts vs allografts (odds ratio, 1.2; 95% CI, 0.3-4.8). CONCLUSIONS The overall risk for deep wound infections following ACL reconstruction is low but it does vary by graft type. Infection risk was highest in hamstring autograft recipients compared with allograft recipients and bone-patellar tendon-bone autograft recipients. Infect Control Hosp Epidemiol 2016;37:827-833. PMID:27340734

  20. Long-term outcomes of allograft reconstruction of the anterior cruciate ligament.

    PubMed

    Lenehan, Eric A; Payne, W Barrett; Askam, Brad M; Grana, William A; Farrow, Lutul D

    2015-05-01

    Recent studies have found higher rates of failed reconstruction of the anterior cruciate ligament (ACL) with use of allograft when compared with autograft reconstruction. To evaluate the long-term outcomes of allograft ACL reconstruction, we retrospectively reviewed the cases of all patients who underwent allograft (n=99) or autograft (n=24) ACL reconstruction by 2 senior surgeons at a single institution over an 8-year period. Seventeen (17%) of the 99 allograft reconstructions required additional surgery. Reoperation and revision ACL reconstruction rates (30.8% and 20.5%, respectively) were much higher for patients 25 years of age or younger than for patients older than 25 years. In our cohort of NCAA (National Collegiate Athletic Association) Division I athletes, the revision ACL reconstruction rate was 62% for allograft ACL reconstruction and 0% for autograft reconstruction. Our study found that reoperation and revision rates for irradiated soft-tissue allograft ACL reconstruction were higher than generally quoted for autograft reconstruction. Given the extremely high graft failure rates in patients younger than 25 years, we recommend against routine use of irradiated soft-tissue allograft for ACL reconstruction in younger patients. PMID:25950536

  1. Long-term outcomes of allograft reconstruction of the anterior cruciate ligament.

    PubMed

    Lenehan, Eric A; Payne, W Barrett; Askam, Brad M; Grana, William A; Farrow, Lutul D

    2015-05-01

    Recent studies have found higher rates of failed reconstruction of the anterior cruciate ligament (ACL) with use of allograft when compared with autograft reconstruction. To evaluate the long-term outcomes of allograft ACL reconstruction, we retrospectively reviewed the cases of all patients who underwent allograft (n=99) or autograft (n=24) ACL reconstruction by 2 senior surgeons at a single institution over an 8-year period. Seventeen (17%) of the 99 allograft reconstructions required additional surgery. Reoperation and revision ACL reconstruction rates (30.8% and 20.5%, respectively) were much higher for patients 25 years of age or younger than for patients older than 25 years. In our cohort of NCAA (National Collegiate Athletic Association) Division I athletes, the revision ACL reconstruction rate was 62% for allograft ACL reconstruction and 0% for autograft reconstruction. Our study found that reoperation and revision rates for irradiated soft-tissue allograft ACL reconstruction were higher than generally quoted for autograft reconstruction. Given the extremely high graft failure rates in patients younger than 25 years, we recommend against routine use of irradiated soft-tissue allograft for ACL reconstruction in younger patients.

  2. Image reconstruction by the speckle-masking method.

    PubMed

    Weigelt, G; Wirnitzer, B

    1983-07-01

    Speckle masking is a method for reconstructing high-resolution images of general astronomical objects from stellar speckle interferograms. In speckle masking no unresolvable star is required within the isoplanatic patch of the object. We present digital applications of speckle masking to close spectroscopic double stars. The speckle interferograms were recorded with the European Southern Observatory's 3.6-m telescope. Diffraction-limited resolution (0.03 arc see) was achieved, which is about 30 times higher than the resolution of conventional astrophotography.

  3. Image reconstruction by the speckle-masking method.

    PubMed

    Weigelt, G; Wirnitzer, B

    1983-07-01

    Speckle masking is a method for reconstructing high-resolution images of general astronomical objects from stellar speckle interferograms. In speckle masking no unresolvable star is required within the isoplanatic patch of the object. We present digital applications of speckle masking to close spectroscopic double stars. The speckle interferograms were recorded with the European Southern Observatory's 3.6-m telescope. Diffraction-limited resolution (0.03 arc see) was achieved, which is about 30 times higher than the resolution of conventional astrophotography. PMID:19718124

  4. Accelerated signal encoding and reconstruction using pixon method

    DOEpatents

    Puetter, Richard; Yahil, Amos; Pina, Robert

    2005-05-17

    The method identifies a Pixon element, which is a fundamental and indivisible unit of information, and a Pixon basis, which is the set of possible functions from which the Pixon elements are selected. The actual Pixon elements selected from this basis during the reconstruction process represents the smallest number of such units required to fit the data and representing the minimum number of parameters necessary to specify the image. The Pixon kernels can have arbitrary properties (e.g., shape, size, and/or position) as needed to best fit the data.

  5. Patient Demographics and Surgical Characteristics in ACL Revision: A Comparison of French, Norwergian, and North American Cohorts

    PubMed Central

    Magnussen, Robert A.; Trojani, Christophe; Granan, Lars-Petter; Neyret, Philippe; Colombet, Philippe; Engebretsen, Lars; Wright, Rick W.; Kaeding, Christopher C.

    2014-01-01

    Purpose The goal of this paper is to compare patient factors, intra-operative findings, and surgical techniques between patients followed in large cohorts in France, Norway, and North America. Methods Data collected on 2286 patients undergoing revision ACLR were obtained. These data included 1216 patients enrolled in the Multicenter ACL Revision Study (MARS) in North America, 793 patients undergoing revision ACLR and recorded in the Norwegian Knee Ligament Registry (NKLR), and 277 patients recorded in the revision ACL database of the Société Française d’Arthroscopie (SFA) in France. Data collected from each database included patient demographics (age, sex, height, and weight), graft choice and reason for failure of the primary ACLR, time from primary to revision ACLR, pre-revision patient-reported outcome scores (KOOS, subjective IKDC), associated intra-articular findings and treatments at revision, and graft choice for revision reconstruction. Results Patient demographics in the three databases were relatively similar. Graft choice for primary and revision ACLR varied significantly, with more allografts used in the MARS cohort. Hamstring autograft was favored in the NKRL, while BTB autograft was most common in the SFA cohort. Reasons for failure of the primary ACLR were comparable, with recurrent trauma noted in 46 to 56% of patients in each of the three cohorts. Technical error was cited in 44 to 51% of patients in the MARS and SFA cohorts, but was not clearly elucidated in the NKLR cohort. Biologic failure of the primary graft was more common in the MARS cohort. Differences in associated intra-articular findings were noted at the time of revision ACLR, with significantly more high grade cartilage lesions noted in the MARS group. Conclusions Significant differences exist between patient populations followed in revision ACL cohorts throughout the world that should be considered when applying findings from such cohorts to different patient populations. PMID

  6. A New Method for Coronal Magnetic Field Reconstruction

    NASA Astrophysics Data System (ADS)

    Yi, Sibaek; Choe, Gwangson; Lim, Daye

    2015-08-01

    We present a new, simple, variational method for reconstruction of coronal force-free magnetic fields based on vector magnetogram data. Our method employs vector potentials for magnetic field description in order to ensure the divergence-free condition. As boundary conditions, it only requires the normal components of magnetic field and current density so that the boundary conditions are not over-specified as in many other methods. The boundary normal current distribution is initially fixed once and for all and does not need continual adjustment as in stress-and-relax type methods. We have tested the computational code based on our new method in problems with known solutions and those with actual photospheric data. When solutions are fully given at all boundaries, the accuracy of our method is almost comparable to best performing methods in the market. When magnetic field data are given only at the photospheric boundary, our method excels other methods in most “figures of merit” devised by Schrijver et al. (2006). Furthermore the residual force in the solution is at least an order of magnitude smaller than that of any other method. It can also accommodate the source-surface boundary condition at the top boundary. Our method is expected to contribute to the real time monitoring of the sun required for future space weather forecasts.

  7. Post-refinement multiscale method for pin power reconstruction

    SciTech Connect

    Collins, B.; Seker, V.; Downar, T.; Xu, Y.

    2012-07-01

    The ability to accurately predict local pin powers in nuclear reactors is necessary to understand the mechanisms that cause fuel pin failure during steady state and transient operation. In the research presented here, methods are developed to improve the local solution using high order methods with boundary conditions from a low order global solution. Several different core configurations were tested to determine the improvement in the local pin powers compared to the standard techniques based on diffusion theory and pin power reconstruction (PPR). The post-refinement multiscale methods use the global solution to determine boundary conditions for the local solution. The local solution is solved using either a fixed boundary source or an albedo boundary condition; this solution is 'post-refinement' and thus has no impact on the global solution. (authors)

  8. Correlation-Based Image Reconstruction Methods for Magnetic Particle Imaging

    NASA Astrophysics Data System (ADS)

    Ishihara, Yasutoshi; Kuwabara, Tsuyoshi; Honma, Takumi; Nakagawa, Yohei

    Magnetic particle imaging (MPI), in which the nonlinear interaction between internally administered magnetic nanoparticles (MNPs) and electromagnetic waves irradiated from outside of the body is utilized, has attracted attention for its potential to achieve early diagnosis of diseases such as cancer. In MPI, the local magnetic field distribution is scanned, and the magnetization signal from MNPs within a selected region is detected. However, the signal sensitivity and image resolution are degraded by interference from magnetization signals generated by MNPs outside of the selected region, mainly because of imperfections (limited gradients) in the local magnetic field distribution. Here, we propose new methods based on correlation information between the observed signal and the system function—defined as the interaction between the magnetic field distribution and the magnetizing properties of MNPs. We performed numerical analyses and found that, although the images were somewhat blurred, image artifacts could be significantly reduced and accurate images could be reconstructed without the inverse-matrix operation used in conventional image reconstruction methods.

  9. Femoral Condyle Fracture during Revision of Anterior Cruciate Ligament Reconstruction: Case Report and a Review of Literature

    PubMed Central

    Keyhani, Sohrab; Vaziri, Arash Sharafat; shafiei, Hossein; Mardani-Kivi, Mohsen

    2015-01-01

    A rare and devastating complication following anterior cruciate ligament (ACL) revision reconstruction is femoral fracture. A 35-year old male soccer player with a history of ACL tear from one year ago, who underwent arthroscopic ACL reconstruction and functioned well until another similar injury caused ACL re-rupture. Revision of ACL reconstruction was performed and after failure of graft tension during the pumping, a fluoroscopic assessment showed a femoral condyle fracture. The patient referred to our knee clinic and was operated on in two stages first fixation of the fracture and then ACL re-revision after fracture healing was complete. Not inserting multiple guide pins, keeping a safe distance from the posterior cortex and giving more attention during graft tensioning, especially in revision surgeries, are all small points that can reduce the risk of fracture during the revision of ACL reconstruction. PMID:26110183

  10. Increased Compliance With Supervised Rehabilitation Improves Functional Outcome and Return to Sport After Anterior Cruciate Ligament Reconstruction in Recreational Athletes

    PubMed Central

    Han, Fucai; Banerjee, Anirban; Shen, Liang; Krishna, Lingaraj

    2015-01-01

    Background: Successful return to sport is an important outcome measure after anterior cruciate ligament (ACL) reconstruction and a reason for patients’ decisions to elect surgery. Rehabilitation programs supervised by physical therapists are routinely prescribed after ACL reconstruction surgery. However, the added advantage of supervised physical therapy after ACL reconstruction is still debatable. Hypothesis: Attending more supervised physical therapy sessions after arthroscopic ACL reconstruction in recreational athletes increases their chance of successful return to sport. Study Design: Cohort study; Level of evidence, 3. Methods: The authors analyzed 93 recreational athletes who underwent arthroscopic ACL reconstruction. After arthroscopic single-bundle ACL reconstruction, patients were advised to attend 20 supervised physical therapy sessions. Patients’ demographics, surgical details, and outcome measures (Knee injury and Osteoarthritis Outcome Score [KOOS], Lysholm scale, and Short Form–36 Health Survey [SF-36]) were recorded presurgery and at 1-year follow-up. Ability to return to sports was documented through patients’ self-report. The attendance at physical therapy by each patient was obtained by examining database records and assessed as fully compliant (>15 sessions), moderately compliant (6-15 sessions), or noncompliant (<6 sessions). Results: Patients in the fully compliant group had significantly greater odds (odds ratio [OR], 18.5; 95% CI, 1.9-184.5; P = .013) of a successful return to sport as compared with the noncompliant group. Patients in the moderately compliant group also had greater odds of returning to sport as compared with the noncompliant group (OR, 4.2; 95% CI, 1.0-16.6; P = .043). Patients in the fully compliant group had significantly greater scores on the Lysholm (P < .001), KOOS Sports and Recreation subscale (P = .021), KOOS Symptoms subscale (P = .040), and SF-36 physical component summary (PCS) (P = .012) as compared with

  11. [The effect of central anatomical single-bundle versus anatomical double-bundle reconstruction of the anterior cruciate ligament on knee stability. a clinical study].

    PubMed

    Komzák, M; Hart, R; Smíd, P; Puskeiler, M

    2014-01-01

    PURPOSE OF THE STUDY A comparison of the efficacy of central anatomical single-bundle (CASB) reconstruction with that of double-bundle (DB) repair of the anterior cruciate ligament (ACL) in relation to knee stability in anteroposterior translation (APT), internal rotation (IR) and external rotation (ER) of the joint. MATERIAL AND METHODS A total of 40 patients were evaluated; 20 had ACL reconstruction by the CASB technique using hamstrings and 20 underwent DB repair surgery. The average age was 31.3 years, and the group included 22 men and 18 women with 19 right and 21 left knees. The KT-1000 test was used to assess the amount of APT in the knee and rotational deviations were measured by the Rolimeter. In the DB patients, measurements were performed before surgery (on joints with ACL injury), then after reconstruction of the anteromedial (AM) or the posterolateral (PL) bundle and subsequently after repair of both ACL bundles. The CASB patients were assessed before and after graft insertion. RESULTS The average APT value was 18.5 mm for the pre-operative knees and it fell to 8.9 mm after AM bundle reconstruction. However, when the PL bundle was inserted in the first place, the average APT value was 13.1 mm only. The average values recorded after the DB and CASB reconstructions were 6.1 mm and 9.1 mm, respectively. The average IR range of motion in the pre-operative joints was 18.6 degrees. After AM bundle reconstruction it was 13.9 degrees and after PL bundle repair it was 15.3 degrees. In DB reconstruction the average IR value achieved 10.4 degrees, and in CASB repair surgery it was 13.7 degrees. The average ER range of motion in the pre-operative joints was 17.8 degrees. After AM bundle reconstruction it was 14.5 degrees and after PL bundle repair it was 14.9 degrees. In DB reconstruction the average ER value achieved 11.4 degrees, and in CASB repair surgery it was 14.5 degrees. DISCUSSION Rotational stability of the knee after ACL reconstruction is one of the

  12. Anterior cruciate ligament reconstruction in patients older than 35 years.

    PubMed

    El-Sallakh, Sameh; Pastides, Philip; Thomas, Panos

    2014-12-01

    Anterior cruciate ligament (ACL) reconstruction is an increasingly established method even in patients older than 35 years. Our hypothesis is that functional outcome after ACL reconstruction is comparable in patients younger and older than 35 years. A total of 28 patients (5 women and 23 men) with average age of 41.5 years (36-68) were retrospectively evaluated. The average follow-up period was 33 months. All of them were treated operatively with arthroscopic single-bundle four-strand hamstring tendon autograft. The functional outcome was determined by clinical scores (Tegner activity scale and Lysholm knee score). The median values for the Lysholm knee score were preoperatively 77 and postoperatively 96 points (range, 90-100) with significant improvement (p < 0.05) and that for the Tegner activity scale were preoperatively 4.6 points (range, 3-6), which is the same pre- and postoperatively with an overall return to baseline for all patients. No significant correlation between functional outcome and patients' age was present and no reported significant complications. The good results and a high level of patient satisfaction show that ACL reconstruction is justified even in patients (older than 35 years) with symptomatic anterior knee instability. We commonly propose surgical treatment in symptomatic patients who express the need to restore their preinjury activity levels, regardless of their age.

  13. Correlation Analysis of Potential Factors Influencing Graft Maturity After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Li, Hong; Chen, Shuang; Tao, Hongyue; Li, Hongyun; Chen, Shiyi

    2014-01-01

    Background: Postoperatively, signal changes of the reconstructed anterior cruciate ligament (ACL) graft on magnetic resonance imaging (MRI) images commonly occurs, which may be a cause for concern. The signal intensity changes are usually expressed by signal/noise quotient (SNQ) value, representing graft maturity. To date, little is known about the factors influencing the SNQ value of the reconstructed ACL graft. Purpose: To evaluate ACL graft SNQ value and associated factors after ACL reconstruction. Study Design: Case series; Level of evidence, 4. Methods: Male patients who underwent ACL reconstruction using autograft or allograft tendon from September 2004 to September 2011 were randomly invited to take part in this investigation, including functional scores, physical examination, and MRI scan. The femoral side graft was fixed with Endobutton CL or Rigidfix pins, and the tibial side graft was fixed with a bio-intrafix. SNQ values of each graft were measured on MRI to represent graft maturity. Sagittal ACL angle, ACL–Blumensaat line angle, and medial and lateral posterior tibial slope (PTS) were measured using MRI 3-dimensional dual-echo steady-state images. Potential risk factors, including age, body mass index, postoperative time, Tegner activity scale (TAS), sagittal ACL angle, ACL–Blumensaat line angle, medial PTS, lateral PTS, and primary graft diameter, were tested for their association with the graft SNQ value by multivariate stepwise regression analysis. Results: A total of 104 male subjects (mean follow-up, 30.7 months) were examined, including 62 allograft and 42 autograft reconstructions. There was a significant association between graft SNQ and postoperative time (r = −0.431, P < .001), TAS (r = 0.295, P = .002), and ACL–Blumensaat line angle (r = −0.304, P = .002). Univariate regression analysis showed that TAS (β = 6.15, P < .001) positively correlated, postoperative time (β = −0.26, P < .001) negatively correlated, and ACL

  14. RELIABILITY AND VALIDITY OF A MODIFIED ISOMETRIC DYNAMOMETER IN THE ASSESSMENT OF MUSCULAR PERFORMANCE IN INDIVIDUALS WITH ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

    PubMed Central

    de Vasconcelos, Rodrigo Antunes; Bevilaqua-Grossi, Débora; Shimano, Antonio Carlos; Paccola, Cleber Jansen; Salvini, Tânia Fátima; Prado, Christiane Lanatovits; Junior, Wilson A. Mello

    2015-01-01

    Objectives: The aim of this study was to evaluate the reliability and validity of a modified isometric dynamometer (MID) in performance deficits of the knee extensor and flexor muscles in normal individuals and in those with ACL reconstructions. Methods: Sixty male subjects were invited to participate of the study, being divided into three groups with 20 subjects each: control group (GC), group of individuals with ACL reconstruction with patellar tendon graft (GTP, and group of individuals with ACL reconstruction with hamstrings graft (GTF). All individuals performed isometric tests in the MID, muscular strength deficits collected were subsequently compared to the tests performed on the Biodex System 3 operating in the isometric and isokinetic mode at speeds of 60°/s and 180o/s. Intraclass ICC correlation calculations were done in order to assess MID reliability, specificity, sensitivity and Kappa's consistency coefficient calculations, respectively, for assessing the MID's validity in detecting muscular deficits and intra- and intergroup comparisons when performing the four strength tests using the ANOVA method. Results: The modified isometric dynamometer (MID) showed excellent reliability and good validity in the assessment of the performance of the knee extensor and flexor muscles groups. In the comparison between groups, the GTP showed significantly greater deficits as compared to the GTF and GC groups. Conclusion: Isometric dynamometers connected to mechanotherapy equipments could be an alternative option to collect data concerning performance deficits of the extensor and flexor muscles groups of the knee in subjects with ACL reconstruction. PMID:27004175

  15. Reconstruction of synthetic aperture digital Fresnel hologram by use of the screen division method

    NASA Astrophysics Data System (ADS)

    Jiang, Hongzhen; Zhao, Jianlin; Di, Jianglei

    2014-12-01

    Synthetic aperture digital holography can effectively increase the recording area of digital hologram, which is propitious to extend the range and improve the resolution of the reconstruction image. However, the area of synthetic aperture digital hologram is usually very large, and thus if it is directly reconstructed, the numerical reconstruction process may can't progress in order for the limitation of the disposal capability of computer. Therefore, a screen-division reconstruction method for synthetic aperture digital Fresnel hologram is proposed in the paper. Relatively to the direct reconstruction method, the screen division reconstruction method can effectively reduce the area of the hologram participant in the numerical operation process and thus make it possible to reconstruct the synthetic aperture digital Fresnel hologram which area exceeds the disposal capability of computer. The synthetic aperture digital Fresnel hologram with large area is acquired by the precise control for the removal of CCD array and then reconstructed by the proposed screen division reconstruction method. The experimental results show that, the introduced numerical reconstruction method can well correct the position and phase distribution of the sub-reconstructed-images and obtain accurate synthetic numerical reconstruction image.

  16. Statistics-based reconstruction method with high random-error tolerance for integral imaging.

    PubMed

    Zhang, Juan; Zhou, Liqiu; Jiao, Xiaoxue; Zhang, Lei; Song, Lipei; Zhang, Bo; Zheng, Yi; Zhang, Zan; Zhao, Xing

    2015-10-01

    A three-dimensional (3D) digital reconstruction method for integral imaging with high random-error tolerance based on statistics is proposed. By statistically analyzing the points reconstructed by triangulation from all corresponding image points in an elemental images array, 3D reconstruction with high random-error tolerance could be realized. To simulate the impacts of random errors, random offsets with different error levels are added to a different number of elemental images in simulation and optical experiments. The results of simulation and optical experiments showed that the proposed statistic-based reconstruction method has relatively stable and better reconstruction accuracy than the conventional reconstruction method. It can be verified that the proposed method can effectively reduce the impacts of random errors on 3D reconstruction of integral imaging. This method is simple and very helpful to the development of integral imaging technology.

  17. Comparative Study of Computational Methods for Reconstructing Genetic Networks of Cancer-Related Pathways

    PubMed Central

    Sedaghat, Nafiseh; Saegusa, Takumi; Randolph, Timothy; Shojaie, Ali

    2014-01-01

    Network reconstruction is an important yet challenging task in systems biology. While many methods have been recently proposed for reconstructing biological networks from diverse data types, properties of estimated networks and differences between reconstruction methods are not well understood. In this paper, we conduct a comprehensive empirical evaluation of seven existing network reconstruction methods, by comparing the estimated networks with different sparsity levels for both normal and tumor samples. The results suggest substantial heterogeneity in networks reconstructed using different reconstruction methods. Our findings also provide evidence for significant differences between networks of normal and tumor samples, even after accounting for the considerable variability in structures of networks estimated using different reconstruction methods. These differences can offer new insight into changes in mechanisms of genetic interaction associated with cancer initiation and progression. PMID:25288880

  18. Reducing the Risk of ACL Injury in Female Athletes

    ERIC Educational Resources Information Center

    McDaniel, Larry W.; Rasche, Adrienna; Gaudet, Laura; Jackson, Allen

    2010-01-01

    The Anterior Cruciate Ligament (ACL) is located behind the kneecap (patella) and connects the thigh bone (femur) to the shin bone (tibia). Stabilizing the knee joint is the primary responsibility of the ACL. Injuries that affect the ACL are three to five times more common in females than males. This is a result of anatomical, biomechanical,…

  19. Multi-rater Agreement in the Assessment of Anterior Cruciate Ligament Reconstruction Failure. A Radiographic and Video Analysis of the MARS Cohort

    PubMed Central

    Matava, Matthew J.; Arciero, Robert A.; Baumgarten, Keith M.; Carey, James L.; DeBerardino, Thomas M.; Hame, Sharon L.; Hannafin, Jo A.; Miller, Bruce S.; Nissen, Carl W.; Taft, Timothy N.; Wolf, Brian R.; Wright, Rick W.

    2015-01-01

    Background ACL reconstruction failure occurs in up to 10% of cases. Technical errors are considered the most common cause of graft failure despite the absence of validated studies. There is limited data regarding the agreement among orthopedic surgeons in terms of the etiology of primary ACL reconstruction failure and accuracy of graft tunnel placement. Purpose The purpose of this study is to test the hypothesis that experienced knee surgeons have a high level of inter-observer reliability in the agreement of the etiology of the primary ACL reconstruction failure, anatomical graft characteristics, tunnel placement. Methods Twenty cases of revision ACL reconstruction were randomly selected from the MARS database. Each case included the patient's history, standardized radiographs, and a concise 30-second arthroscopic video taken at the time of revision demonstrating the graft remnant and location of the tunnel apertures. 10 MARS surgeons not involved with the primary surgery reviewed all 20 cases. Each surgeon completed a two-part questionnaire dealing with each surgeon's training and practice as well as the placement of the femoral and tibial tunnels, condition of the primary graft, and the surgeon's opinion as to the etiology of graft failure. Inter-rater agreement was determined for each question. Inter-rater agreement was determined for each question with the kappa coefficient and prevalence adjusted bias adjusted kappa (PABAK). Results The 10 reviewers were in practice an average of 14 years. All performed at least 25 ACL reconstructions per year and 9 were fellowship-trained in sports medicine. There was wide variability in agreement among knee experts as to the specific etiology of ACL graft failure. When specifically asked about technical error as the cause for failure, inter-observer agreement was only slight (prevalence adjusted bias adjusted kappa [PABAK]: 0.26). There was fair overall agreement on ideal femoral tunnel placement (PABAK: 0.55), but only

  20. A CLASS OF RECONSTRUCTED DISCONTINUOUS GALERKIN METHODS IN COMPUTATIONAL FLUID DYNAMICS

    SciTech Connect

    Hong Luo; Yidong Xia; Robert Nourgaliev

    2011-05-01

    A class of reconstructed discontinuous Galerkin (DG) methods is presented to solve compressible flow problems on arbitrary grids. The idea is to combine the efficiency of the reconstruction methods in finite volume methods and the accuracy of the DG methods to obtain a better numerical algorithm in computational fluid dynamics. The beauty of the resulting reconstructed discontinuous Galerkin (RDG) methods is that they provide a unified formulation for both finite volume and DG methods, and contain both classical finite volume and standard DG methods as two special cases of the RDG methods, and thus allow for a direct efficiency comparison. Both Green-Gauss and least-squares reconstruction methods and a least-squares recovery method are presented to obtain a quadratic polynomial representation of the underlying linear discontinuous Galerkin solution on each cell via a so-called in-cell reconstruction process. The devised in-cell reconstruction is aimed to augment the accuracy of the discontinuous Galerkin method by increasing the order of the underlying polynomial solution. These three reconstructed discontinuous Galerkin methods are used to compute a variety of compressible flow problems on arbitrary meshes to assess their accuracy. The numerical experiments demonstrate that all three reconstructed discontinuous Galerkin methods can significantly improve the accuracy of the underlying second-order DG method, although the least-squares reconstructed DG method provides the best performance in terms of both accuracy, efficiency, and robustness.

  1. Trends in primary and revision anterior cruciate ligament reconstruction among National Basketball Association team physicians.

    PubMed

    Mall, Nathan A; Abrams, Geoffrey D; Azar, Frederick M; Traina, Steve M; Allen, Answorth A; Parker, Richard; Cole, Brian J

    2014-06-01

    Anterior cruciate ligament (ACL) tears are common in athletes. Techniques and methods of treatment for these injuries continue to vary among surgeons. Thirty National Basketball Association (NBA) team physicians were surveyed during the NBA Pre-Draft Combine. Survey questions involved current and previous practice methods of primary and revision ACL reconstruction, including technique, graft choice, rehabilitation, and treatment of combined ACL and medial collateral ligament injuries. Descriptive parametric statistics, Fisher exact test, and logistic regression were used, and significance was set at α = 0.05. All 30 team physicians completed the survey. Eighty-seven percent indicated they use autograft (81% bone-patellar tendon-bone) for primary ACL reconstruction in NBA athletes, and 43% indicated they use autograft for revision cases. Fourteen surgeons (47%) indicated they use an anteromedial portal (AMP) for femoral tunnel drilling, whereas 5 years earlier only 4 (13%) used this technique. There was a significant (P = .009) positive correlation between fewer years in practice and AMP use. NBA team physicians' use of an AMP for femoral tunnel drilling has increased over the past 5 years.

  2. Vector intensity reconstruction using the data completion method.

    PubMed

    Langrenne, Christophe; Garcia, Alexandre

    2013-04-01

    This paper presents an application of the data completion method (DCM) for vector intensity reconstructions. A mobile array of 36 pressure-pressure probes (72 microphones) is used to perform measurements near a planar surface. Nevertheless, since the proposed method is based on integral formulations, DCM can be applied with any kind of geometry. This method requires the knowledge of Cauchy data (pressure and velocity) on a part of the boundary of an empty domain in order to evaluate pressure and velocity on the remaining part of the boundary. Intensity vectors are calculated in the interior domain surrounded by the measurement array. This inverse acoustic problem requires the use of a regularization method to obtain a realistic solution. An experiment in a closed wooden car trunk mock-up excited by a shaker and two loudspeakers is presented. In this case, where the volume of the mock-up is small (0.61 m(3)), standing-waves and fluid structure interactions appear and show that DCM is a powerful tool to identify sources in a confined space. PMID:23556589

  3. An iterative method for the reconstruction of the coronary arteries from rotational x-ray angiography

    NASA Astrophysics Data System (ADS)

    Hansis, Eberhard; Schäfer, Dirk; Grass, Michael; Dössel, Olaf

    2007-03-01

    Three-dimensional (3D) reconstruction of the coronary arteries offers great advantages in the diagnosis and treatment of cardiovascular diseases, compared to two-dimensional X-ray angiograms. Besides improved roadmapping, quantitative analysis of vessel lesions is possible. To perform 3D reconstruction, rotational projection data of the selectively contrast agent enhanced coronary arteries are acquired with simultaneous ECG recording. For the reconstruction of one cardiac phase, the corresponding projections are selected from the rotational sequence by nearest-neighbor ECG gating. This typically provides only 5-10 projections per cardiac phase. The severe angular undersampling leads to an ill-posed reconstruction problem. In this contribution, an iterative reconstruction method is presented which employs regularizations especially suited for the given reconstruction problem. The coronary arteries cover only a small fraction of the reconstruction volume. Therefore, we formulate the reconstruction problem as a minimization of the L I-norm of the reconstructed image, which results in a spatially sparse object. Two additional regularization terms are introduced: a 3D vesselness prior, which is reconstructed from vesselness-filtered projection data, and a Gibbs smoothing prior. The regularizations favor the reconstruction of the desired object, while taking care not to over-constrain the reconstruction by too detailed a-priori assumptions. Simulated projection data of a coronary artery software phantom are used to evaluate the performance of the method. Human data of clinical cases are presented to show the method's potential for clinical application.

  4. Randomized Trial of a Novel ACLS Teaching Tool: Does it Improve Student Performance?

    PubMed Central

    Nacca, Nicholas; Holliday, Jordan; Ko, Paul Y.

    2014-01-01

    Introduction Mounting evidence suggests that high-fidelity mannequin-based (HFMBS) and computer-based simulation are useful adjunctive educational tools for advanced cardiac life support (ACLS) instruction. We sought to determine whether access to a supplemental, online computer-based ACLS simulator would improve students’ performance on a standardized Mega Code using high-fidelity mannequin based simulation (HFMBS). Methods Sixty-five third-year medical students were randomized. Intervention group subjects (n = 29) each received a two-week access code to the online ACLS simulator, whereas the control group subjects (n = 36) did not. Primary outcome measures included students’ time to initiate chest compressions, defibrillate ventricular fibrillation, and pace symptomatic bradycardia. Secondary outcome measures included students’ subjective self-assessment of ACLS knowledge and confidence. Results Students with access to the online simulator on average defibrillated ventricular fibrillation in 112 seconds, whereas those without defibrillated in 149.9 seconds, an average of 38 seconds faster [p<.05]. Similarly, those with access to the simulator paced symptomatic bradycardia on average in 95.14 seconds whereas those without access paced on average 154.9 seconds a difference of 59.81 seconds [p<.05]. On a subjective 5-point scale, there was no difference in self-assessment of ACLS knowledge between the control (mean 3.3) versus intervention (mean 3.1) [p-value =.21]. Despite having outperformed the control group subjects in the standardized Mega Code test scenario, the intervention group felt less confident on a 5-point scale (mean 2.5) than the control group. (mean 3.2) [p<.05] Conclusion The reduction in time to defibrillate ventricular fibrillation and to pace symptomatic bradycardia among the intervention group subjects suggests that the online computer-based ACLS simulator is an effective adjunctive ACLS instructional tool. PMID:25493153

  5. Functional Performance Testing After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Abrams, Geoffrey D.; Harris, Joshua D.; Gupta, Anil K.; McCormick, Frank M.; Bush-Joseph, Charles A.; Verma, Nikhil N.; Cole, Brian J.; Bach, Bernard R.

    2014-01-01

    Background: When to allow an athlete to return to unrestricted sporting activity after anterior cruciate ligament (ACL) reconstruction remains controversial. Purpose: To report the results of functional performance testing reported in the literature for individuals at differing time points following ACL reconstruction and to examine differences between graft types. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review of Medline, Scopus, and Cochrane Central Register of Controlled Trials was performed using PRISMA guidelines. Inclusion criteria were English-language studies that examined any functional rehabilitation test from 6 months to 2 years following ACL reconstruction. All patient-, limb-, and knee-specific demographics were extracted from included investigations. All functional rehabilitation tests were analyzed and compared when applicable. Results: The search term returned a total of 890 potential studies, with 88 meeting inclusion and exclusion criteria. A total of 4927 patients were included, of which 66% were male. The mean patient age was 26.5 ± 3.4 years. The predominant graft choices for reconstruction were bone–patellar tendon–bone (BPTB) autograft (59.8%) and hamstring autograft (37.9%). The most commonly reported functional tests were the hop tests. The results of these functional tests, as reported in the Limb Symmetry Index (LSI), improved with increasing time, with nearly all results greater than 90% at 1 year following primary ACL reconstruction. At 6 months postoperatively, a number of isokinetic strength measurements failed to reach 80% LSI, most commonly isokinetic knee extension testing in both BPTB and hamstring autograft groups. The knee flexion strength deficit was significantly less in the BPTB autograft group as compared with those having hamstring autograft at 1 year postoperatively, while no significant differences were found in isokinetic extension strength between the 2 groups. Conclusion: Hop

  6. Revision anterior cruciate ligament reconstruction with bone-patellar tendon-bone allograft and extra-articular iliotibial band tenodesis.

    PubMed

    Mascarenhas, Randy; McConkey, Mark O; Forsythe, Brian; Harner, Christopher D

    2015-04-01

    Revision anterior cruciate ligament (ACL) reconstruction is a technically demanding procedure with outcomes that generally fail to reach those seen with primary ACL reconstruction. With most index procedures using autograft tissue, it is not uncommon for allograft tissue to be required for revision ACL reconstruction. Compared with autografts, allografts take longer to incorporate and lead to more episodes of instability. In this article, we describe ipsilateral iliotibial band tenodesis performed to augment use of bone-patellar tendon-bone allograft in revision ACL reconstruction. This technique adds rotational stability to protect the allograft tissue while it incorporates. PMID:25844596

  7. Revision anterior cruciate ligament reconstruction with bone-patellar tendon-bone allograft and extra-articular iliotibial band tenodesis.

    PubMed

    Mascarenhas, Randy; McConkey, Mark O; Forsythe, Brian; Harner, Christopher D

    2015-04-01

    Revision anterior cruciate ligament (ACL) reconstruction is a technically demanding procedure with outcomes that generally fail to reach those seen with primary ACL reconstruction. With most index procedures using autograft tissue, it is not uncommon for allograft tissue to be required for revision ACL reconstruction. Compared with autografts, allografts take longer to incorporate and lead to more episodes of instability. In this article, we describe ipsilateral iliotibial band tenodesis performed to augment use of bone-patellar tendon-bone allograft in revision ACL reconstruction. This technique adds rotational stability to protect the allograft tissue while it incorporates.

  8. Pliocene paleoclimatic reconstruction using dinoflagellate cysts: Comparison of methods

    USGS Publications Warehouse

    Edwards, L.E.; Mudie, P.J.; de Vernal, A.

    1991-01-01

    The application of quantitative and semiquantitative methods to assemblage data from dinoflagellate cysts shows potential for interpreting past environments, both in terms of paleotemperature estimates and in recognizing water masses and circulation patterns. Estimates of winter sea-surface temperature (WSST) were produced by using the Impagidinium Index (II) method, and by applying a winter-temperature transfer function (TFw). Estimates of summer sea-surface temperature (SSST) were produced by using a summer-temperature transfer function (TFs), two methods based on a temperature-distribution chart (ACT and ACTpo), and a method based on the ratio of gonyaulacoid:protoperidinioid specimens (G:P). WSST estimates from the II and TFw methods are in close agreement except where Impagidinium species are sparse. SSST estimates from TFs are more variable. The value of the G:P ratio for the Pliocene data in this paper is limited by the apparent sparsity of protoperidinioids, which results in monotonous SSST estimates of 14-26??C. The ACT methods show two biases for the Pliocene data set: taxonomic substitution may force 'matches' yielding incorrect temperature estimates, and the method is highly sensitive to the end-points of species distributions. Dinocyst assemblage data were applied to reconstruct Pliocene sea-surface temperatures between 3.5-2.5 Ma from DSDP Hole 552A, and ODP Holes 646B and 642B, which are presently located beneath cold and cool-temperate waters north of 56??N. Our initial results suggest that at 3.0 Ma, WSSTs were a few degrees C warmer than the present and that there was a somewhat reduced north-south temperature gradient. For all three sites, it is likely that SSSTs were also warmer, but by an unknown, perhaps large, amount. Past oceanic circulation in the North Atlantic was probably different from the present. ?? 1991.

  9. Anterior cruciate ligament reconstruction with fresh-frozen patellar tendon allografts: sixty cases with 2 years' minimum follow-up.

    PubMed

    Nín, J R; Leyes, M; Schweitzer, D

    1996-01-01

    A prospective study was performed on 101 patients who underwent an arthroscopic anterior cruciate ligament (ACL) reconstruction with fresh-frozen patellar tendon allograft (bone-patellar tendon-bone). We present the results of the first 60 patients with a minimum follow-up of 2 years. Thirty-four were men and 26 women with a mean age of 23. In 45 patients, a postoperative arthroscopy was performed, and tissue biopsies of the reconstructed ACL were obtained. Patients were evaluated according to the International Knee Documentation Committee evaluation form. After a mean follow-up of 47 months, the overall results were normal or nearly normal in 85%. Under postoperative arthroscopy, the macroscopic appearance of the implant was similar to that of a normal ligament. The ACL allograft was covered with a normal, well-vascularized synovium. There were no cases of infection, disease transmission or tissue rejection. We conclude that the use of fresh-frozen patellar tendon allografts is a good method of ACL reconstruction.

  10. Anterior cruciate ligament reconstruction with fresh-frozen patellar tendon allografts: sixty cases with 2 years' minimum follow-up.

    PubMed

    Nín, J R; Leyes, M; Schweitzer, D

    1996-01-01

    A prospective study was performed on 101 patients who underwent an arthroscopic anterior cruciate ligament (ACL) reconstruction with fresh-frozen patellar tendon allograft (bone-patellar tendon-bone). We present the results of the first 60 patients with a minimum follow-up of 2 years. Thirty-four were men and 26 women with a mean age of 23. In 45 patients, a postoperative arthroscopy was performed, and tissue biopsies of the reconstructed ACL were obtained. Patients were evaluated according to the International Knee Documentation Committee evaluation form. After a mean follow-up of 47 months, the overall results were normal or nearly normal in 85%. Under postoperative arthroscopy, the macroscopic appearance of the implant was similar to that of a normal ligament. The ACL allograft was covered with a normal, well-vascularized synovium. There were no cases of infection, disease transmission or tissue rejection. We conclude that the use of fresh-frozen patellar tendon allografts is a good method of ACL reconstruction. PMID:8961227

  11. Investigating 3d Reconstruction Methods for Small Artifacts

    NASA Astrophysics Data System (ADS)

    Evgenikou, V.; Georgopoulos, A.

    2015-02-01

    Small artifacts have always been a real challenge when it comes to 3D modelling. They usually present severe difficulties for their 3D reconstruction. Lately, the demand for the production of 3D models of small artifacts, especially in the cultural heritage domain, has dramatically increased. As with many cases, there are no specifications and standards for this task. This paper investigates the efficiency of several mainly low cost methods for 3D model production of such small artifacts. Moreover, the material, the color and the surface complexity of these objects id also investigated. Both image based and laser scanning methods have been considered as alternative data acquisition methods. The evaluation has been confined to the 3D meshes, as texture depends on the imaging properties, which are not investigated in this project. The resulting meshes have been compared to each other for their completeness, and accuracy. It is hoped that the outcomes of this investigation will be useful to researchers who are planning to embark into mass production of 3D models of small artifacts.

  12. Reconstruction of the anterior cruciate ligament with the tendons of the semitendinosus and gracilis doubled: a comparison with reconstruction using the patellar tendon.

    PubMed

    Iorio, R; Ciardini, R; Russo, A; Conteduca, F; Ferretti, A

    2005-01-01

    A total of sixty consecutive cases of anterior chronic laxity of the knee the pre- and intraoperative features of which corresponded to the criteria of inclusion considered, hospitalized in our institute between September and December 1998 and submitted to reconstruction of the ACL were reviewed at a follow-up of 74 months. The series was made up of two groups that were homogeneous in terms of sex, age, degree of preoperative laxity and number and type of associated meniscal lesions; in the first group (20 cases) reconstruction was carried out using the patellar tendon (BPTB) and in the other (40 cases) the doubled semitendinosus and gracilis tendons (DGST) were used with the association in cases with greater rotatory laxity (20 cases) of peripheral reinforcement reconstruction. An accelerated rehabilitation protocol was used in the first group, a more prudent one with immobilization in extension for two weeks was used in the second group. The results, evaluated based on the IKDC form, appeared to be better in the DGST group, with a statistically significant difference; joint stability, evaluated at follow-up with a KT1000 arthrometer also proved to be better in the DGST group, with a difference that was not statistically significant. The present study seems to show that reconstruction of the ACL with DGST, a prudent rehabilitation protocol and peripheral reinforcement reconstruction in selected cases is capable of providing better long-term results as compared to standard reconstruction with the patellar tendon and accelerated rehabilitation protocol. Among methods used to reconstruct the anterior cruciate ligament (ACL), those that utilize the central third of the patellar tendon (BPTB) or the semitendinosus and gracilis tendons (DGST) continue to be those used most frequently. Although the debate between orthopedics is still going on as to which of the two methods is to be preferred, studies that compare the two methods do not seem to report essential

  13. Irregular seismic data reconstruction based on exponential threshold model of POCS method

    NASA Astrophysics Data System (ADS)

    Gao, Jian-Jun; Chen, Xiao-Hong; Li, Jing-Ye; Liu, Guo-Chang; Ma, Jian

    2010-09-01

    Irregular seismic data causes problems with multi-trace processing algorithms and degrades processing quality. We introduce the Projection onto Convex Sets (POCS) based image restoration method into the seismic data reconstruction field to interpolate irregularly missing traces. For entire dead traces, we transfer the POCS iteration reconstruction process from the time to frequency domain to save computational cost because forward and reverse Fourier time transforms are not needed. In each iteration, the selection threshold parameter is important for reconstruction efficiency. In this paper, we designed two types of threshold models to reconstruct irregularly missing seismic data. The experimental results show that an exponential threshold can greatly reduce iterations and improve reconstruction efficiency compared to a linear threshold for the same reconstruction result. We also analyze the antinoise and anti-alias ability of the POCS reconstruction method. Finally, theoretical model tests and real data examples indicate that the proposed method is efficient and applicable.

  14. Results of meniscectomy and meniscal repair in anterior cruciate ligament reconstruction

    PubMed Central

    DELEDDA, DAVIDE; ROSSO, FEDERICA; COTTINO, UMBERTO; BONASIA, DAVIDE EDOARDO; ROSSI, ROBERTO

    2015-01-01

    Meniscal tears are commonly associated with anterior cruciate ligament (ACL) injuries. A deficient medial meniscus results in knee instability and could lead to higher stress forces on the ACL reconstruction. Comparison of results in meniscectomy and meniscal repairs revealed worse clinical outcomes in meniscectomy, but higher re-operation rates in meniscal repairs. Our aim was to review the results of ACL reconstruction associated with meniscectomy or meniscal repair. PMID:26889472

  15. Reconstructing palaeoclimatic variables from fossil pollen using boosted regression trees: comparison and synthesis with other quantitative reconstruction methods

    NASA Astrophysics Data System (ADS)

    Salonen, J. Sakari; Luoto, Miska; Alenius, Teija; Heikkilä, Maija; Seppä, Heikki; Telford, Richard J.; Birks, H. John B.

    2014-03-01

    We test and analyse a new calibration method, boosted regression trees (BRTs) in palaeoclimatic reconstructions based on fossil pollen assemblages. We apply BRTs to multiple Holocene and Lateglacial pollen sequences from northern Europe, and compare their performance with two commonly-used calibration methods: weighted averaging regression (WA) and the modern-analogue technique (MAT). Using these calibration methods and fossil pollen data, we present synthetic reconstructions of Holocene summer temperature, winter temperature, and water balance changes in northern Europe. Highly consistent trends are found for summer temperature, with a distinct Holocene thermal maximum at ca 8000-4000 cal. a BP, with a mean Tjja anomaly of ca +0.7 °C at 6 ka compared to 0.5 ka. We were unable to reconstruct reliably winter temperature or water balance, due to the confounding effects of summer temperature and the great between-reconstruction variability. We find BRTs to be a promising tool for quantitative reconstructions from palaeoenvironmental proxy data. BRTs show good performance in cross-validations compared with WA and MAT, can model a variety of taxon response types, find relevant predictors and incorporate interactions between predictors, and show some robustness with non-analogue fossil assemblages.

  16. An Improved Total Variation Minimization Method Using Prior Images and Split-Bregman Method in CT Reconstruction

    PubMed Central

    2016-01-01

    Compressive Sensing (CS) theory has great potential for reconstructing Computed Tomography (CT) images from sparse-views projection data and Total Variation- (TV-) based CT reconstruction method is very popular. However, it does not directly incorporate prior images into the reconstruction. To improve the quality of reconstructed images, this paper proposed an improved TV minimization method using prior images and Split-Bregman method in CT reconstruction, which uses prior images to obtain valuable previous information and promote the subsequent imaging process. The images obtained asynchronously were registered via Locally Linear Embedding (LLE). To validate the method, two studies were performed. Numerical simulation using an abdomen phantom has been used to demonstrate that the proposed method enables accurate reconstruction of image objects under sparse projection data. A real dataset was used to further validate the method. PMID:27689076

  17. An Improved Total Variation Minimization Method Using Prior Images and Split-Bregman Method in CT Reconstruction

    PubMed Central

    2016-01-01

    Compressive Sensing (CS) theory has great potential for reconstructing Computed Tomography (CT) images from sparse-views projection data and Total Variation- (TV-) based CT reconstruction method is very popular. However, it does not directly incorporate prior images into the reconstruction. To improve the quality of reconstructed images, this paper proposed an improved TV minimization method using prior images and Split-Bregman method in CT reconstruction, which uses prior images to obtain valuable previous information and promote the subsequent imaging process. The images obtained asynchronously were registered via Locally Linear Embedding (LLE). To validate the method, two studies were performed. Numerical simulation using an abdomen phantom has been used to demonstrate that the proposed method enables accurate reconstruction of image objects under sparse projection data. A real dataset was used to further validate the method.

  18. High-quality image reconstruction method for ptychography with partially coherent illumination

    NASA Astrophysics Data System (ADS)

    Yu, Wei; Wang, Shouyu; Veetil, Suhas; Gao, Shumei; Liu, Cheng; Zhu, Jianqiang

    2016-06-01

    The influence of partial coherence on the image reconstruction in ptychography is analyzed, and a simple method is proposed to reconstruct a clear image for the weakly scattering object with partially coherent illumination. It is demonstrated numerically and experimentally that by illuminating a weakly scattering object with a divergent radiation beam, and doing the reconstruction only from the bright-field diffraction data, the mathematical ambiguity and corresponding reconstruction errors related to the partial coherency can be remarkably suppressed, thus clear reconstructed images can be generated even under seriously incoherent illumination.

  19. Septic arthritis of the knee following anterior cruciate ligament reconstruction: results of a survey of sports medicine fellowship directors.

    PubMed

    Matava, M J; Evans, T A; Wright, R W; Shively, R A

    1998-10-01

    To determine the incidence of joint sepsis following anterior cruciate ligament (ACL) reconstruction and the prevailing attitudes toward its treatment, we surveyed the directors of Sports Medicine Fellowship programs about their practices in treating and preventing this complication. Of the 74 surgeons surveyed, 61 (82%) responded. These 61 surgeons performed an average of 98 ACL reconstructions yearly; 31 (51 %) routinely used a drain after ACL surgery, 18 (30%) had treated an ACL infection within the past 2 years, and 26 (43%) had treated an infection within the past 5 years. There was no significant difference in the number of infections and the surgeons' case load, graft choice, or method of reconstruction. Fifty-two surgeons (85%) selected culture-specific intravenous (IV) antibiotics and surgical irrigation of the joint with graft retention as initial treatment for the infected patellar tendon autograft, and 39 (64%) chose this regimen to treat the infected allograft. For the resistant infection unresponsive to initial treatment, IV antibiotics with surgical irrigation and graft retention were also selected as the most common treatment combination for 25 (39%) of the 61 respondents. After graft removal, the earliest a revision procedure would be considered was 6 to 9 months. The results of this survey confirm the widely held belief that septic arthritis of the knee is a relatively rare complication following ACL reconstruction. Once an infection is encountered, culture-specific IV antibiotics and surgical joint irrigation with graft retention are recommended as initial treatment. Graft excision and hardware removal is considered only for those infections resistant to initial treatment and for the infected allograft.

  20. Septic arthritis of the knee following anterior cruciate ligament reconstruction: results of a survey of sports medicine fellowship directors.

    PubMed

    Matava, M J; Evans, T A; Wright, R W; Shively, R A

    1998-10-01

    To determine the incidence of joint sepsis following anterior cruciate ligament (ACL) reconstruction and the prevailing attitudes toward its treatment, we surveyed the directors of Sports Medicine Fellowship programs about their practices in treating and preventing this complication. Of the 74 surgeons surveyed, 61 (82%) responded. These 61 surgeons performed an average of 98 ACL reconstructions yearly; 31 (51 %) routinely used a drain after ACL surgery, 18 (30%) had treated an ACL infection within the past 2 years, and 26 (43%) had treated an infection within the past 5 years. There was no significant difference in the number of infections and the surgeons' case load, graft choice, or method of reconstruction. Fifty-two surgeons (85%) selected culture-specific intravenous (IV) antibiotics and surgical irrigation of the joint with graft retention as initial treatment for the infected patellar tendon autograft, and 39 (64%) chose this regimen to treat the infected allograft. For the resistant infection unresponsive to initial treatment, IV antibiotics with surgical irrigation and graft retention were also selected as the most common treatment combination for 25 (39%) of the 61 respondents. After graft removal, the earliest a revision procedure would be considered was 6 to 9 months. The results of this survey confirm the widely held belief that septic arthritis of the knee is a relatively rare complication following ACL reconstruction. Once an infection is encountered, culture-specific IV antibiotics and surgical joint irrigation with graft retention are recommended as initial treatment. Graft excision and hardware removal is considered only for those infections resistant to initial treatment and for the infected allograft. PMID:9788367

  1. Improving tissue segmentation of human brain MRI through preprocessing by the Gegenbauer reconstruction method.

    PubMed

    Archibald, Rick; Chen, Kewei; Gelb, Anne; Renaut, Rosemary

    2003-09-01

    The Gegenbauer image reconstruction method, previously shown to improve the quality of magnetic resonance images, is utilized in this study as a segmentation preprocessing step. It is demonstrated that, for all simulated and real magnetic resonance images used in this study, the Gegenbauer reconstruction method improves the accuracy of segmentation. Although it is more desirable to use the k-space data for the Gegenbauer reconstruction method, only information acquired from MR images is necessary for the reconstruction, making the procedure completely self-contained and viable for all human brain segmentation algorithms. PMID:14527609

  2. Evaluation of a 3D point cloud tetrahedral tomographic reconstruction method

    PubMed Central

    Pereira, N F; Sitek, A

    2011-01-01

    Tomographic reconstruction on an irregular grid may be superior to reconstruction on a regular grid. This is achieved through an appropriate choice of the image space model, the selection of an optimal set of points and the use of any available prior information during the reconstruction process. Accordingly, a number of reconstruction-related parameters must be optimized for best performance. In this work, a 3D point cloud tetrahedral mesh reconstruction method is evaluated for quantitative tasks. A linear image model is employed to obtain the reconstruction system matrix and five point generation strategies are studied. The evaluation is performed using the recovery coefficient, as well as voxel- and template-based estimates of bias and variance measures, computed over specific regions in the reconstructed image. A similar analysis is performed for regular grid reconstructions that use voxel basis functions. The maximum likelihood expectation maximization reconstruction algorithm is used. For the tetrahedral reconstructions, of the five point generation methods that are evaluated, three use image priors. For evaluation purposes, an object consisting of overlapping spheres with varying activity is simulated. The exact parallel projection data of this object are obtained analytically using a parallel projector, and multiple Poisson noise realizations of these exact data are generated and reconstructed using the different point generation strategies. The unconstrained nature of point placement in some of the irregular mesh-based reconstruction strategies has superior activity recovery for small, low-contrast image regions. The results show that, with an appropriately generated set of mesh points, the irregular grid reconstruction methods can out-perform reconstructions on a regular grid for mathematical phantoms, in terms of the performance measures evaluated. PMID:20736496

  3. Prehospital ACLS--does it work?

    PubMed

    Maheshwari, Alok; Mehrotra, Avanti; Gupta, Anoop K; Thakur, Ranjan K

    2002-11-01

    Cardiac disease is the most common cause of death in the United States, and sudden cardiac arrest frequently claims the lives of men and women during their most productive years. It is believed that much better survival rates can be achieved for victims of cardiac arrest through optimizing the "chain of survival" as described by the American Heart Association. The relative and incremental benefit of full prehospital ACLS over basic life support and defibrillation is unproven, however. This is an important issue in this era of cost containment. Some of the ongoing studies including the OPALS study may clarify the cost effectiveness and relative efficacy of rapid defibrillation and full ACLS programs for victims of prehospital cardiac arrest [6].

  4. Popliteus function in ACL-deficient patients.

    PubMed

    Weresh, M J; Gabel, R H; Brand, R A; Tearse, D S

    1997-02-01

    Anterior cruciate ligament (ACL) injuries commonly result in anterolateral rotary instability and a 'pivot shift' phenomenon. Since popliteus muscle stimulation causes a pivot shift, some postulate the popliteus muscle plays a role in causing pivot shifts. To see if patients with pivot shifts exhibited excessive popliteus muscle activity, we studied fine-wire EMGs of the popliteus in 16 normal subjects and 10 ACL-deficient subjects. Subjects performed six activities (level walking and jogging, ascending walking and jogging, and descending walking and jogging). Except for minor timing differences in ascending treadmill and ascending jogging, the signals were similar for injured and uninjured limbs; similar variance ratios suggested similar pattern variability. Thus, we observed only minor popliteus EMG signal differences in this group of patients. We conclude that the popliteus muscle does not actively contribute to instability in the studied activities.

  5. Sex differences in knee strength deficit 1 year after anterior cruciate ligament reconstruction

    PubMed Central

    Kim, Do Kyung; Park, Won Hah

    2015-01-01

    [Purpose] Little is known about the outcome differences between men and women after anterior cruciate ligament (ACL) reconstruction. Therefore, the present study aimed to compare knee muscle strength between men and women 1 year after ACL reconstruction. [Subjects and Methods] Retrospective and outcome study. Between 2012 and 2015, 35 males (mean age, 29.7 ± 010.7 years) and 35 females (mean age, 28.2 ± 11.3 years) who had undergone primary ACL reconstruction were recruited from Samsung medical centers. We assessed the strength deficit in the quadriceps (extensor) and hamstrings (flexor) at 60°/sec and 180°/sec with isokinetic testing equipment. Statistical analysis was conducted with a t-test to determine if sex differences existed in knee strength deficit. [Results] Significant differences were noted between men and women with respect to extensor muscle strength deficit. Women reported less extensor muscle strength than men did, at the angular velocities 60°/sec and 180°/sec. However, no significant sex differences were found at either velocity with respect to the strength deficit of the knee flexor muscles. [Conclusion] Compared to male patients, female patients reported significantly less extensor muscle strength and less improvement 1 year after reconstruction. PMID:26834366

  6. Popliteus function in ACL-deficient patients.

    PubMed

    Weresh, M J; Gabel, R H; Brand, R A; Tearse, D S

    1994-01-01

    Anterior cruciate ligament (ACL) injuries commonly result in anterolateral instability, resulting in a "pivot shift" phenomenon. Given that popliteus muscle stimulation results in a pivot shift, others have postulated that the popliteus muscle has a role in the pivot shift phenomenon. We hypothesized that patients with instability from ACL injuries may have excessive popliteus muscle activity. Therefore, we studied the EMG activity (using fine wire electrodes) of the popliteus muscle in sixteen normal subjects and ten ACL-deficient subjects. We recorded the EMG in six activities (level walking and jogging, ascending walking and jogging, and descending walking and jogging). Person's Product Moment Correlations were above 0.7, except in the case of ascending the treadmill (r = 0.427) and ascending jogging (r = 0.645), suggesting that the timing of the signals was similar for injured and uninjured limbs. Variance ratios for the injured and uninjured limbs were statistically similar, suggesting similar variability of patterns. Thus, we observed only minor popliteus EMG signal differences in this group of patients. We conclude that the popliteus muscle does not contribute to instability in the studied activities.

  7. Influence of the crosshead rate on the mechanical properties of fixation systems of ACL tendon grafts.

    PubMed

    Martel, Oscar; Cárdenes, Juan F; Garcés, Gerardo; Carta, José A

    2009-11-01

    Anterior cruciate ligament (ACL) reconstruction is one of the most important aspects of knee surgery. For this purpose, several fixation devices have been developed, although the interference screw is the most frequently used. The most typical biomechanical test of these devices consists of placing them in a testing machine and subjecting them to a pull-out test. However, insufficient attention has been paid to the influence of the displacement test rate on the mechanical properties of the fixation system. The aim of this study is to compare the influence of the crosshead rate in the biomechanical test of two different devices for the fixation of ACL tendon grafts. One hundred in vitro tests were performed using porcine tibiae and bovine tendons. The fixation devices used were (1) an interference screw and (2) a new expansion device. All ACL reconstructions were subjected to pull-out test to failure. Five crosshead rates were employed in a range from 30 mm/min to 4000 mm/min. Statistical analyses of the results show that, for the two devices, the rate has a significant effect on both maximum force and stiffness. Moreover, the new expansion device showed lesser dependency on the crosshead rate than the interference screw.

  8. Anatomical anterior cruciate ligament reconstruction: transtibial versus outside-in technique

    PubMed Central

    MATASSI, FABRIZIO; SIRLEO, LUIGI; CARULLI, CHRISTIAN; INNOCENTI, MASSIMO

    2015-01-01

    Purpose the aim of this study was to compare clinical results and location of the femoral tunnel with transtibial (TT) and outside-in (OI) techniques in anterior cruciate ligament (ACL) reconstruction using in vivo 3D CT analysis. Methods we prospectively followed up 40 ACL reconstructions in which femoral tunnel placement was performed using two different techniques: TT [20] and OI [20]. Clinical evaluation was based on IKDC and KOOS scores and radiographic analysis with specific 3D CT scans. Tunnel coordinates were calculated using the Bernard-Hertel quadrant method to define the insertion point of the ACL. Results excellent clinical results were achieved in both groups, which showed comparable IKDC and KOOS scores. Two failures were recorded, both in the TT group. In the high-to-low direction, the position of the femoral tunnel, as measured using the quadrant method, was too high in the TT group, compared to what was observed in the OI group: 10.5 ± 6.9% (0–29%) and 30.2 ± 5.4% (19–42%), (p=0.043). Conclusions we found that with the TT technique, compared with the OI technique, the femoral tunnel was located higher in the high-to-low direction and was in a slightly shallower position in the deep-to-shallow direction. Using the OI technique the femoral tunnel was in a position closer to the anatomical ACL footprint than with the TT technique. A femoral tunnel position far from the anatomical footprint of the native ACL would result in a higher failure rate. Level of evidence level II, prospective comparative study. PMID:26151033

  9. A novel method for the 3-D reconstruction of scoliotic ribs from frontal and lateral radiographs.

    PubMed

    Seoud, Lama; Cheriet, Farida; Labelle, Hubert; Dansereau, Jean

    2011-05-01

    Among the external manifestations of scoliosis, the rib hump, which is associated with the ribs' deformities and rotations, constitutes the most disturbing aspect of the scoliotic deformity for patients. A personalized 3-D model of the rib cage is important for a better evaluation of the deformity, and hence, a better treatment planning. A novel method for the 3-D reconstruction of the rib cage, based only on two standard radiographs, is proposed in this paper. For each rib, two points are extrapolated from the reconstructed spine, and three points are reconstructed by stereo radiography. The reconstruction is then refined using a surface approximation. The method was evaluated using clinical data of 13 patients with scoliosis. A comparison was conducted between the reconstructions obtained with the proposed method and those obtained by using a previous reconstruction method based on two frontal radiographs. A first comparison criterion was the distances between the reconstructed ribs and the surface topography of the trunk, considered as the reference modality. The correlation between ribs axial rotation and back surface rotation was also evaluated. The proposed method successfully reconstructed the ribs of the 6th-12th thoracic levels. The evaluation results showed that the 3-D configuration of the new rib reconstructions is more consistent with the surface topography and provides more accurate measurements of ribs axial rotation.

  10. Exploring Normalization and Network Reconstruction Methods using In Silico and In Vivo Models

    EPA Science Inventory

    Abstract: Lessons learned from the recent DREAM competitions include: The search for the best network reconstruction method continues, and we need more complete datasets with ground truth from more complex organisms. It has become obvious that the network reconstruction methods t...

  11. Advanced Cardiac Life Support (ACLS) utilizing Man-Tended Capability (MTC) hardware onboard Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Smith, M.; Barratt, M.; Lloyd, C.

    1992-01-01

    Because of the time and distance involved in returning a patient from space to a definitive medical care facility, the capability for Advanced Cardiac Life Support (ACLS) exists onboard Space Station Freedom. Methods: In order to evaluate the effectiveness of terrestrial ACLS protocols in microgravity, a medical team conducted simulations during parabolic flights onboard the KC-135 aircraft. The hardware planned for use during the MTC phase of the space station was utilized to increase the fidelity of the scenario and to evaluate the prototype equipment. Based on initial KC-135 testing of CPR and ACLS, changes were made to the ventricular fibrillation algorithm in order to accommodate the space environment. Other constraints to delivery of ACLS onboard the space station include crew size, minimum training, crew deconditioning, and limited supplies and equipment. Results: The delivery of ACLS in microgravity is hindered by the environment, but should be adequate. Factors specific to microgravity were identified for inclusion in the protocol including immediate restraint of the patient and early intubation to insure airway. External cardiac compressions of adequate force and frequency were administered using various methods. The more significant limiting factors appear to be crew training, crew size, and limited supplies. Conclusions: Although ACLS is possible in the microgravity environment, future evaluations are necessary to further refine the protocols. Proper patient and medical officer restraint is crucial prior to advanced procedures. Also emphasis should be placed on early intubation for airway management and drug administration. Preliminary results and further testing will be utilized in the design of medical hardware, determination of crew training, and medical operations for space station and beyond.

  12. Investigation on reconstruction methods applied to 3D terahertz computed tomography.

    PubMed

    Recur, B; Younus, A; Salort, S; Mounaix, P; Chassagne, B; Desbarats, P; Caumes, J-P; Abraham, E

    2011-03-14

    3D terahertz computed tomography has been performed using a monochromatic millimeter wave imaging system coupled with an infrared temperature sensor. Three different reconstruction methods (standard back-projection algorithm and two iterative analysis) have been compared in order to reconstruct large size 3D objects. The quality (intensity, contrast and geometric preservation) of reconstructed cross-sectional images has been discussed together with the optimization of the number of projections. Final demonstration to real-life 3D objects has been processed to illustrate the potential of the reconstruction methods for applied terahertz tomography.

  13. Electrical impedance tomography method for reconstruction of biological tissues with continuous plane-stratification.

    PubMed

    Dolgin, M; Einziger, P D

    2006-01-01

    A novel electrical impedance tomography method is introduced for reconstruction of layered biological tissues with continuous plane-stratification. The algorithm implements the recently proposed reconstruction scheme for piecewise constant conductivity profiles, based on an improved Prony method in conjunction with Legendre polynomial expansion (LPE). It is shown that the proposed algorithm is capable of successfully reconstructing continuous conductivity profiles with moderate (WKB) slop. Features of the presented reconstruction scheme include, an inherent linearity, achieved by the linear LPE transform, a locality feature, assigning analytically to each spectral component a local electrical impedance associated with a unique location, and effective performance even in the presence of noisy measurements.

  14. ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING THE DOUBLE-BUNDLE TECHNIQUE – EVALUATION IN THE BIOMECHANICS LABORATORY

    PubMed Central

    D'Elia, Caio Oliveira; Bitar, Alexandre Carneiro; Castropil, Wagner; Garofo, Antônio Guilherme Padovani; Cantuária, Anita Lopes; Orselli, Maria Isabel Veras; Luques, Isabela Ugo; Duarte, Marcos

    2015-01-01

    Objective: The objective of this study was to describe the methodology of knee rotation analysis using biomechanics laboratory instruments and to present the preliminary results from a comparative study on patients who underwent anterior cruciate ligament (ACL) reconstruction using the double-bundle technique. Methods: The protocol currently used in our laboratory was described. Three-dimensional kinematic analysis was performed and knee rotation amplitude was measured on eight normal patients (control group) and 12 patients who were operated using the double-bundle technique, by means of three tasks in the biomechanics laboratory. Results: No significant differences between operated and non-operated sides were shown in relation to the mean amplitudes of gait, gait with change in direction or gait with change in direction when going down stairs (p > 0.13). Conclusion: The preliminary results did not show any difference in the double-bundle ACL reconstruction technique in relation to the contralateral side and the control group. PMID:27027003

  15. On multigrid methods for image reconstruction from projections

    SciTech Connect

    Henson, V.E.; Robinson, B.T.; Limber, M.

    1994-12-31

    The sampled Radon transform of a 2D function can be represented as a continuous linear map R : L{sup 1} {yields} R{sup N}. The image reconstruction problem is: given a vector b {element_of} R{sup N}, find an image (or density function) u(x, y) such that Ru = b. Since in general there are infinitely many solutions, the authors pick the solution with minimal 2-norm. Numerous proposals have been made regarding how best to discretize this problem. One can, for example, select a set of functions {phi}{sub j} that span a particular subspace {Omega} {contained_in} L{sup 1}, and model R : {Omega} {yields} R{sup N}. The subspace {Omega} may be chosen as a member of a sequence of subspaces whose limit is dense in L{sup 1}. One approach to the choice of {Omega} gives rise to a natural pixel discretization of the image space. Two possible choices of the set {phi}{sub j} are the set of characteristic functions of finite-width `strips` representing energy transmission paths and the set of intersections of such strips. The authors have studied the eigenstructure of the matrices B resulting from these choices and the effect of applying a Gauss-Seidel iteration to the problem Bw = b. There exists a near null space into which the error vectors migrate with iteration, after which Gauss-Seidel iteration stalls. The authors attempt to accelerate convergence via a multilevel scheme, based on the principles of McCormick`s Multilevel Projection Method (PML). Coarsening is achieved by thickening the rays which results in a much smaller discretization of an optimal grid, and a halving of the number of variables. This approach satisfies all the requirements of the PML scheme. They have observed that a multilevel approach based on this idea accelerates convergence at least to the point where noise in the data dominates.

  16. Digital reconstructed radiography quality control with software methods

    NASA Astrophysics Data System (ADS)

    Denis, Eloise; Beaumont, Stephane; Guedon, JeanPierre

    2005-04-01

    Nowadays, most of treatments for external radiotherapy are prepared with Treatment Planning Systems (TPS) which uses a virtual patient generated by a set of transverse slices acquired with a CT scanner of the patient in treatment position 1 2 3. In the first step of virtual simulation, the TPS is used to define a ballistic allowing a good target covering and the lowest irradiation for normal tissues. This parameters optimisation of the treatment with the TPS is realised with particular graphic tools allowing to: ×Contour the target, ×Expand the limit of the target in order to take into account contouring uncertainties, patient set up errors, movements of the target during the treatment (internal movement of the target and external movement of the patient), and beam's penumbra, ×Determine beams orientation and define dimensions and forms of the beams, ×Visualize beams on the patient's skin and calculate some characteristic points which will be tattooed on the patient to assist the patient set up before treating, ×Calculate for each beam a Digital Reconstructed Radiography (DRR) consisting in projecting the 3D CT virtual patient and beam limits with a cone beam geometry onto a plane. These DRR allow one for insuring the patient positioning during the treatment, essentially bone structures alignment by comparison with real radiography realized with the treatment X-ray source in the same geometric conditions (portal imaging). Then DRR are preponderant to insure the geometric accuracy of the treatment. For this reason quality control of its computation is mandatory4 . Until now, this control is realised with real test objects including some special inclusions4 5 . This paper proposes to use some numerical test objects to control the quality DRR calculation in terms of computation time, beam angle, divergence and magnification precision, spatial and contrast resolutions. The main advantage of this proposed method is to avoid a real test object CT acquisition

  17. Synchronous quadriceps tendon rupture and unilateral ACL tear in a weightlifter, associated with anabolic steroid use.

    PubMed

    Fenelon, Christopher; Dalton, David M; Galbraith, John G; Masterson, Eric L

    2016-05-06

    Synchronous quadriceps tendon rupture is rare. A 29-year-old man, an amateur weight lifter, taking androgenic-anabolic steroids (AAS), developed sudden onset bilateral pain and swelling of his anterior thighs when attempting to squat 280 kg (620 lb). Examination revealed gross swelling superior to the patella and palpable gaps in both quadriceps tendons. He underwent successful operative repair. MRI revealed a partial tear of the anterior cruciate ligament (ACL) of the right knee. This was not reconstructed. Only a few case reports of the association between AAS and quadriceps rupture exist in the literature, with none to the best of our knowledge in the past 10 years. ACL rupture coexisting is very rare, with only two reported cases.

  18. Synchronous quadriceps tendon rupture and unilateral ACL tear in a weightlifter, associated with anabolic steroid use.

    PubMed

    Fenelon, Christopher; Dalton, David M; Galbraith, John G; Masterson, Eric L

    2016-01-01

    Synchronous quadriceps tendon rupture is rare. A 29-year-old man, an amateur weight lifter, taking androgenic-anabolic steroids (AAS), developed sudden onset bilateral pain and swelling of his anterior thighs when attempting to squat 280 kg (620 lb). Examination revealed gross swelling superior to the patella and palpable gaps in both quadriceps tendons. He underwent successful operative repair. MRI revealed a partial tear of the anterior cruciate ligament (ACL) of the right knee. This was not reconstructed. Only a few case reports of the association between AAS and quadriceps rupture exist in the literature, with none to the best of our knowledge in the past 10 years. ACL rupture coexisting is very rare, with only two reported cases. PMID:27154985

  19. Should critical care nurses be ACLS-trained?

    PubMed

    Hagyard-Wiebe, Tammy

    2007-01-01

    The aim of resuscitation is to sustain life with intact neurological functioning and the same quality of life previously experienced by the patient. Advanced cardiac life support (ACLS) was designed to achieve this aim. However the requirement for ACLS training for critical care nurses working in Canadian critical care units is inconsistent across the country. The purposes of this article are to explore the evidence surrounding ACLS training for critical care nurses and its impact on resuscitation outcomes, and to review the evidence surrounding ACLS knowledge and skill degradation with strategies to support code blue team efficiency for an effective resuscitation. Using the search terms ACLS training, resuscitation, critical care, and nursing, two databases, CINAHL and MEDLINE, were used. The evidence supports the need for ACLS training for critical care nurses. The evidence also supports organized ongoing refresher courses, multidisciplinary mock code blue practice using technologically advanced simulator mannequins, and videotaped reviews to prevent knowledge and skill degradation for effective resuscitation efforts.

  20. Patellar tendon or hamstring graft anterior cruciate ligament reconstructions in patients aged above 50 years

    PubMed Central

    Bali, Tarun; Nagraj, Raghu; Kumar, Malhar N; Chandy, Thomas

    2015-01-01

    Background: The treatment of anterior cruciate ligament (ACL) injury consists of arthroscopic ACL reconstruction with patellar tendon or hamstring graft. Satisfactory results have been reported so far in the younger age group. Dilemma arises regarding the suitability of ACL reconstruction in patients aged 50 years and above. This retrospective analyses the outcome of ACL reconstruction in patients aged 50 years and above. Materials and Methods: 55 patients aged 50 years and above presented to our institution with symptomatic ACL tear and were managed with arthroscopic reconstruction with patellar tendon/hamstring graft. 22 patients underwent ACL reconstruction with bone- patellar tendon-bone graft and the remaining 33 with a hamstring graft. Evaluation of functional outcome was performed using International Knee Documentation Committee (IKDC) and Lysholm scoring in the preoperative period, at the end of 1 year and at the final followup. Radiographic evaluation was performed using the Kellgren–Lawrence grading system. Results: The mean preoperative IKDC score was 39.7 ± 3.3. At the end of 1-year following the operation, the mean IKDC score was 73.6 ± 4.9 and at the final followup was 67.8 ± 7.7. The mean preoperative Lysholm score was 40.4 ± 10.3. At the end of 1-year following the intervention, the mean Lysholm score was 89.7 ± 2.1 and at final followup was 85.3 ± 2.5. Overall, 14 out of 42 patients who underwent radiographic assessment showed progression of osteoarthritis changes at the final followup after the intervention. Conclusion: In our study, there was a statistically significant improvement in the IKDC and Lysholm scores following the intervention. There was a slight deterioration in the scores at the final followup but the overall rate of satisfaction was still high and most of the patients were able to do their routine chores and light exercises suitable for their age group. Around one-third of patients show progression of radiographic changes

  1. Rehabilitation concerns following anterior cruciate ligament reconstruction.

    PubMed

    Frndak, P A; Berasi, C C

    1991-11-01

    Rehabilitation following anterior cruciate ligament reconstruction is a subject of controversy in the orthopaedic and rehabilitation literature. With an increasing number of these operations currently being performed and with the advent of arthroscopically assisted ACL reconstruction over the past several years, particular rehabilitation needs and problems have been identified in association with these patients. Various authors have stressed one or a combination of a few basic themes which outline the basic rehabilitation concerns following ACL reconstruction. The most fundamental concern is the need to initiate motion very soon after surgery. Prolonged postoperative immobilisation is known to cause serious complications after ACL reconstruction which can be avoided by early motion. Positions or activities which may apply excessive stress to a newly reconstructed ACL must also be considered. The amount of protection required by the graft will vary depending upon the type of graft used and the quality of fixation obtained intraoperatively. Most authors agree that nonweightbearing, active resistive quadriceps exercises should be avoided for an extended period, while closed chain exercises may be initiated much earlier. Strength recovery is obviously important for the quadriceps postoperatively, but maximal strength returns of all of the muscles about the knee must be pursued. Hamstring strength is of particular concern as this may provide an active support to the reconstructed ACL. Sensory loss in the knee after ACL disruption should also be addressed during rehabilitation, prior to a patient's return to full athletic activity. Progressive neuromuscular re-education exercises which rely on sensory input from intact pericapsular structures are encouraged. A final concern is the role of bracing after ACL reconstruction.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1763251

  2. Direct Visualization of Existing Footprint and Outside-In Drilling of the Femoral Tunnel in Anterior Cruciate Ligament Reconstruction in the Knee

    PubMed Central

    Sutter, E. Grant; Anderson, John A.; Garrett, William E.

    2015-01-01

    Improper femoral tunnel placement in anterior cruciate ligament (ACL) reconstruction is a significant problem and may be a cause of ACL graft failure and abnormal kinematics, which may lead to late degenerative changes after reconstruction. Recently, there has been concern that the transtibial approach may contribute to nonanatomic placement of the femoral tunnel, resulting in abnormal knee kinematics. Tibial-independent techniques can provide more anatomic placement of the ACL graft, but these can be technically demanding. This technical note describes the senior author's technique to directly identify the femoral ACL remnant and use the center of the femoral ACL footprint and retrograde drilling to create an anatomic femoral socket for single-bundle reconstruction. This technique provides femoral tunnel placement based on identification of a patient-specific ACL footprint instead of averaged anatomic measurements from large groups. This technique has been shown to produce anatomic ACL graft position and orientation and restore more normal knee kinematics. PMID:26052485

  3. A new method to combine 3D reconstruction volumes for multiple parallel circular cone beam orbits

    PubMed Central

    Baek, Jongduk; Pelc, Norbert J.

    2010-01-01

    Purpose: This article presents a new reconstruction method for 3D imaging using a multiple 360° circular orbit cone beam CT system, specifically a way to combine 3D volumes reconstructed with each orbit. The main goal is to improve the noise performance in the combined image while avoiding cone beam artifacts. Methods: The cone beam projection data of each orbit are reconstructed using the FDK algorithm. When at least a portion of the total volume can be reconstructed by more than one source, the proposed combination method combines these overlap regions using weighted averaging in frequency space. The local exactness and the noise performance of the combination method were tested with computer simulations of a Defrise phantom, a FORBILD head phantom, and uniform noise in the raw data. Results: A noiseless simulation showed that the local exactness of the reconstructed volume from the source with the smallest tilt angle was preserved in the combined image. A noise simulation demonstrated that the combination method improved the noise performance compared to a single orbit reconstruction. Conclusions: In CT systems which have overlap volumes that can be reconstructed with data from more than one orbit and in which the spatial frequency content of each reconstruction can be calculated, the proposed method offers improved noise performance while keeping the local exactness of data from the source with the smallest tilt angle. PMID:21089770

  4. Influence of patellar ligament insertion angle on quadriceps usage during walking in anterior cruciate ligament reconstructed subjects.

    PubMed

    Shin, Choongsoo S; Chaudhari, Ajit M; Dyrby, Chris O; Andriacchi, Thomas P

    2009-06-01

    Reduced quadriceps contraction has been suggested as an adaptation to prevent anterior tibial translation in anterior cruciate ligament (ACL)-deficient knees. This theory has been supported by a recent study that peak knee flexion moment (thought to be created by a decrease of quadriceps contraction) during walking was negatively correlated with patellar ligament insertion angle (PLIA) in ACL-deficient knees, but not in contralateral, uninjured knees. In addition, the PLIA was significantly smaller in ACL-deficient knees than in contralateral, uninjured knees. However, it is unknown whether ACL reconstruction restores the PLIA or whether the relationship between the PLIA and knee flexion moments previously observed in ACL-deficient knees disappears. This study tested the following hypotheses: (1) The PLIA of ACL-reconstructed knees is significantly smaller than the PLIA of uninjured contralateral knees; (2) Peak knee flexion moment (balanced by net quadriceps moment) during walking is negatively correlated with the PLIA in ACL-reconstructed knees. The PLIA of 24 ACL-reconstructed and contralateral knees were measured using MRI, and peak knee flexion moments during walking were measured. Results showed that the PLIA of ACL-reconstructed (22.9 +/- 4.4 degrees) knees was not significantly smaller (p = 0.09, power = 0.99) than the PLIA of contralateral (24.1 +/- 4.8 degrees) knees. Peak knee flexion moment was not correlated with the PLIA following ACL reconstruction (R2 = 0.016, power = 0.99). However, the magnitude of the knee flexion moment remained significantly lower in ACL-reconstructed knees. In summary, this study has shown that the PLIA of ACL-reconstructed knees returned to normal and that patients no longer adapt their gait in response to the PLIA, though quadriceps function did not return to normal levels.

  5. L1/2 regularization based numerical method for effective reconstruction of bioluminescence tomography

    NASA Astrophysics Data System (ADS)

    Chen, Xueli; Yang, Defu; Zhang, Qitan; Liang, Jimin

    2014-05-01

    Even though bioluminescence tomography (BLT) exhibits significant potential and wide applications in macroscopic imaging of small animals in vivo, the inverse reconstruction is still a tough problem that has plagued researchers in a related area. The ill-posedness of inverse reconstruction arises from insufficient measurements and modeling errors, so that the inverse reconstruction cannot be solved directly. In this study, an l1/2 regularization based numerical method was developed for effective reconstruction of BLT. In the method, the inverse reconstruction of BLT was constrained into an l1/2 regularization problem, and then the weighted interior-point algorithm (WIPA) was applied to solve the problem through transforming it into obtaining the solution of a series of l1 regularizers. The feasibility and effectiveness of the proposed method were demonstrated with numerical simulations on a digital mouse. Stability verification experiments further illustrated the robustness of the proposed method for different levels of Gaussian noise.

  6. Modified convolution method to reconstruct particle hologram with an elliptical Gaussian beam illumination.

    PubMed

    Wu, Xuecheng; Wu, Yingchun; Yang, Jing; Wang, Zhihua; Zhou, Binwu; Gréhan, Gérard; Cen, Kefa

    2013-05-20

    Application of the modified convolution method to reconstruct digital inline holography of particle illuminated by an elliptical Gaussian beam is investigated. Based on the analysis on the formation of particle hologram using the Collins formula, the convolution method is modified to compensate the astigmatism by adding two scaling factors. Both simulated and experimental holograms of transparent droplets and opaque particles are used to test the algorithm, and the reconstructed images are compared with that using FRFT reconstruction. Results show that the modified convolution method can accurately reconstruct the particle image. This method has an advantage that the reconstructed images in different depth positions have the same size and resolution with the hologram. This work shows that digital inline holography has great potential in particle diagnostics in curvature containers.

  7. LARS Artificial Ligament Versus ABC Purely Polyester Ligament for Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Iliadis, Dimitrios Ph.; Bourlos, Dimitrios N.; Mastrokalos, Dimitrios S.; Chronopoulos, Efstathios; Babis, George C.

    2016-01-01

    Background: Graft choice for anterior cruciate ligament (ACL) reconstruction is of critical importance. Various grafts have been used so far, with autografts long considered the optimal solution for the treatment of ACL-deficient knees. Limited data are available on the long-term survivorship of synthetic grafts. Purpose: To compare the functional outcome and survivorship of ACL reconstructions performed using the LARS (ligament augmentation and reconstruction system) ligament and the ABC (active biosynthetic composite) purely polyester ligament. Study Design: Case series; Level of evidence, 4. Methods: The results of 72 patients who underwent primary arthroscopic ACL reconstruction with the LARS ligament and 31 cases with an ABC purely polyester ligament were reviewed. The mean follow-up periods for the LARS and ABC groups were 9.5 and 5.1 years, respectively. A survivorship analysis of the 2 synthetic grafts was performed using the Kaplan-Meier method with a log-rank test (Mantel-Cox, 95% CI). Lysholm, Tegner activity, Knee injury and Osteoarthritis Outcome Score (KOOS), and International Knee Documentation Committee (IKDC) scores as well as laxity measurements obtained using a KT-1000 arthrometer were recorded for all intact grafts, and a Mann-Whitney U test was used for comparison reasons. Results: The rupture rates for LARS and ABC grafts were 31% (95% CI, 20%-42%) and 42% (95% CI, 25%-59%), respectively. For intact grafts, the mean Lysholm score was good for both groups (90 for the LARS group and 89 for the ABC group), with the majority of patients returning to their preinjury level of activities, and the mean IKDC score was 90 for the LARS group and 86 for the ABC group. Conclusion: The rupture rates of both LARS and ABC grafts were both high. However, the LARS ligament provided significantly better survivorship compared with the ABC ligament at short- to midterm follow-up (95% CI). PMID:27453894

  8. Comparison of reconstruction methods and quantitative accuracy in Siemens Inveon PET scanner

    NASA Astrophysics Data System (ADS)

    Ram Yu, A.; Kim, Jin Su; Kang, Joo Hyun; Moo Lim, Sang

    2015-04-01

    PET reconstruction is key to the quantification of PET data. To our knowledge, no comparative study of reconstruction methods has been performed to date. In this study, we compared reconstruction methods with various filters in terms of their spatial resolution, non-uniformities (NU), recovery coefficients (RCs), and spillover ratios (SORs). In addition, the linearity of reconstructed radioactivity between linearity of measured and true concentrations were also assessed. A Siemens Inveon PET scanner was used in this study. Spatial resolution was measured with NEMA standard by using a 1 mm3 sized 18F point source. Image quality was assessed in terms of NU, RC and SOR. To measure the effect of reconstruction algorithms and filters, data was reconstructed using FBP, 3D reprojection algorithm (3DRP), ordered subset expectation maximization 2D (OSEM 2D), and maximum a posteriori (MAP) with various filters or smoothing factors (β). To assess the linearity of reconstructed radioactivity, image quality phantom filled with 18F was used using FBP, OSEM and MAP (β =1.5 & 5 × 10-5). The highest achievable volumetric resolution was 2.31 mm3 and the highest RCs were obtained when OSEM 2D was used. SOR was 4.87% for air and 3.97% for water, obtained OSEM 2D reconstruction was used. The measured radioactivity of reconstruction image was proportional to the injected one for radioactivity below 16 MBq/ml when FBP or OSEM 2D reconstruction methods were used. By contrast, when the MAP reconstruction method was used, activity of reconstruction image increased proportionally, regardless of the amount of injected radioactivity. When OSEM 2D or FBP were used, the measured radioactivity concentration was reduced by 53% compared with true injected radioactivity for radioactivity <16 MBq/ml. The OSEM 2D reconstruction method provides the highest achievable volumetric resolution and highest RC among all the tested methods and yields a linear relation between the measured and true

  9. Hemi-Bernard method: straightforward reconstruction of lower lip after malignant tumor resection.

    PubMed

    Okochi, Masayuki; Ueda, Kazuki; Okochi, Hiromi

    2015-06-01

    The Bernard method is a straightforward method for reconstructing lower lip defects after tumor resection. However, this method is difficult to apply when the defect is located on the unilateral side of the lower lip. This report describes the reconstruction of unilateral lower lip defects using a modified Bernard method, which is referred to as the hemi-Bernard method. Three patients (2 male and 1 female; mean defect, 55%) underwent reconstruction using the hemi-Bernard method after lower lip malignant tumor resection. No infection or flap necrosis occurred, and none of the 3 patients had difficulty with oral ingestion. Movement of the orbicularis oris muscle was retained in all patients. The hemi-Bernard method is straightforward and has several advantages, including extension of lower lip length. This method could be useful for reconstructing full-thickness defects located on the unilateral side of the lower lip. PMID:25869747

  10. Three-Dimensional MRI-Based Statistical Shape Model and Application to a Cohort of Knees with Acute ACL Injury

    PubMed Central

    Pedoia, Valentina; Lansdown, Drew A.; Zaid, Musa; McCulloch, Charles E.; Souza, Richard; Ma, C. Benjamin; Li, Xiaojuan

    2016-01-01

    Objective The aim of this study is to develop a novel 3D magnetic resonance imaging (MRI)-based Statistical Shape Modeling (SSM) and apply it in knee MRIs in order to extract and compare relevant shapes of the tibia and femur in patients with and without acute ACL injuries. Methods Bilateral MR images were acquired and analyzed for 50 patients with acute ACL injuries and for 19 control subjects. A shape model was extracted for the tibia and femur using an SSM algorithm based on a set of matched landmarks that are computed in a fully automatic manner. Results Shape differences were detected between the knees in the ACL-injury group and control group, suggesting a common shape feature that may predispose these knees to injury. Some of the detected shape features that discriminate between injured and control knees are related to intercondylar width and posterior tibia slope, features that have been suggested in previous studies as ACL morphological risk factors. However, shape modeling has the great potential to quantify these characteristics with a comprehensive description of the surfaces describing complex 3D deformation that cannot be represented with simple geometric indexes. Conclusions 3D MRI-based bone shape quantification has the ability to identify specific anatomic risk factors for ACL injury. A better understanding of the role in bony shape on ligamentous injuries could help in the identification of subjects with an increased risk for an ACL tear and to develop targeted prevention strategies, including education and training. PMID:26050865

  11. A Novel Parallel Method for Speckle Masking Reconstruction Using the OpenMP

    NASA Astrophysics Data System (ADS)

    Li, Xuebao; Zheng, Yanfang

    2016-08-01

    High resolution reconstruction technology is developed to help enhance the spatial resolution of observational images for ground-based solar telescopes, such as speckle masking. Near real-time reconstruction performance is achieved on a high performance cluster using the Message Passing Interface (MPI). However, much time is spent in reconstructing solar subimages in such a speckle reconstruction. We design and implement a novel parallel method for speckle masking reconstruction of solar subimage on a shared memory machine using the OpenMP. Real tests are performed to verify the correctness of our codes. We present the details of several parallel reconstruction steps. The parallel implementation between various modules shows a great speed increase as compared to single thread serial implementation, and a speedup of about 2.5 is achieved in one subimage reconstruction. The timing result for reconstructing one subimage with 256×256 pixels shows a clear advantage with greater number of threads. This novel parallel method can be valuable in real-time reconstruction of solar images, especially after porting to a high performance cluster.

  12. Simple method of modelling of digital holograms registering and their optical reconstruction

    NASA Astrophysics Data System (ADS)

    Evtikhiev, N. N.; Cheremkhin, P. A.; Krasnov, V. V.; Kurbatova, E. A.; Molodtsov, D. Yu; Porshneva, L. A.; Rodin, V. G.

    2016-08-01

    The technique of modeling of digital hologram recording and image optical reconstruction from these holograms is described. The method takes into account characteristics of the object, digital camera's photosensor and spatial light modulator used for digital holograms displaying. Using the technique, equipment can be chosen for experiments for obtaining good reconstruction quality and/or holograms diffraction efficiency. Numerical experiments were conducted.

  13. Digital infrared thermal imaging following anterior cruciate ligament reconstruction.

    PubMed

    Barker, Lauren E; Markowski, Alycia M; Henneman, Kimberly

    2012-03-01

    This case describes the selective use of digital infrared thermal imaging for a 48-year-old woman who was being treated by a physical therapist following left anterior cruciate ligament (ACL) reconstruction with a semitendinosus autograft. PMID:22383168

  14. Comparing Transtibial and Anteromedial Drilling Techniques for Single-bundle Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Sukur, Erhan; Akman, , Yunus Emre; Senel, , Ahmet; Unkar, Ethem Ayhan; Topcu, , Huseyin Nevzat; Ozturkmen, , and Yusuf

    2016-01-01

    Background: Among the many factors that determine the outcome following anterior cruciate ligament (ACL) reconstruction, the position of the femoral tunnel is known to be critically important and is still the subject of extensive research. Objective: We aimed to retrospectively compare the outcomes of arthroscopic ACL reconstruction using transtibial (TT) or anteromedial (AMP) drilling techniques for femoral tunnel placement. Methods: ACL reconstruction was performed using the TT technique in 49 patients and the AMP technique in 56 patients. Lachman and pivot-shift tests, the Lysholm Knee Scale, International Knee Documentation Committee (IKDC) score, Tegner activity scale and visual analog scale (VAS) were used for the clinical and functional evaluation of patients. Time to return to normal life and time to jogging were assessed in addition to the radiological evaluation of femoral tunnel placement. Results: In terms of the Lysholm, IKDC, Tegner score, and stability tests, no significant differences were found between the two groups (p > 0.05). Statistical analysis revealed reduced time to return to normal life and jogging in the AMP group (p < 0.05). The VAS score was also significantly reduced in the AMP group (p < 0.05). The position of the femoral tunnel was anatomically appropriate in 51 patients in the AMP group and 5 patients in the TT group. Conclusion: The AMP technique is superior to the TT technique in creating anatomical femoral tunnel placement during single-bundle ACL reconstruction and provides faster recovery in terms of return to normal life and jogging at short-term follow-up. PMID:27733884

  15. An automated 3D reconstruction method of UAV images

    NASA Astrophysics Data System (ADS)

    Liu, Jun; Wang, He; Liu, Xiaoyang; Li, Feng; Sun, Guangtong; Song, Ping

    2015-10-01

    In this paper a novel fully automated 3D reconstruction approach based on low-altitude unmanned aerial vehicle system (UAVs) images will be presented, which does not require previous camera calibration or any other external prior knowledge. Dense 3D point clouds are generated by integrating orderly feature extraction, image matching, structure from motion (SfM) and multi-view stereo (MVS) algorithms, overcoming many of the cost, time limitations of rigorous photogrammetry techniques. An image topology analysis strategy is introduced to speed up large scene reconstruction by taking advantage of the flight-control data acquired by UAV. Image topology map can significantly reduce the running time of feature matching by limiting the combination of images. A high-resolution digital surface model of the study area is produced base on UAV point clouds by constructing the triangular irregular network. Experimental results show that the proposed approach is robust and feasible for automatic 3D reconstruction of low-altitude UAV images, and has great potential for the acquisition of spatial information at large scales mapping, especially suitable for rapid response and precise modelling in disaster emergency.

  16. A new nonlinear reconstruction method based on total variation regularization of neutron penumbral imaging

    SciTech Connect

    Qian Weixin; Qi Shuangxi; Wang Wanli; Cheng Jinming; Liu Dongbing

    2011-09-15

    Neutron penumbral imaging is a significant diagnostic technique in laser-driven inertial confinement fusion experiment. It is very important to develop a new reconstruction method to improve the resolution of neutron penumbral imaging. A new nonlinear reconstruction method based on total variation (TV) regularization is proposed in this paper. A TV-norm is used as regularized term to construct a smoothing functional for penumbral image reconstruction in the new method, in this way, the problem of penumbral image reconstruction is transformed to the problem of a functional minimization. In addition, a fixed point iteration scheme is introduced to solve the problem of functional minimization. The numerical experimental results show that, compared to linear reconstruction method based on Wiener filter, the TV regularized nonlinear reconstruction method is beneficial to improve the quality of reconstructed image with better performance of noise smoothing and edge preserving. Meanwhile, it can also obtain the spatial resolution with 5 {mu}m which is higher than the Wiener method.

  17. Image reconstruction based on L1 regularization and projection methods for electrical impedance tomography.

    PubMed

    Wang, Qi; Wang, Huaxiang; Zhang, Ronghua; Wang, Jinhai; Zheng, Yu; Cui, Ziqiang; Yang, Chengyi

    2012-10-01

    Electrical impedance tomography (EIT) is a technique for reconstructing the conductivity distribution by injecting currents at the boundary of a subject and measuring the resulting changes in voltage. Image reconstruction in EIT is a nonlinear and ill-posed inverse problem. The Tikhonov method with L(2) regularization is always used to solve the EIT problem. However, the L(2) method always smoothes the sharp changes or discontinue areas of the reconstruction. Image reconstruction using the L(1) regularization allows addressing this difficulty. In this paper, a sum of absolute values is substituted for the sum of squares used in the L(2) regularization to form the L(1) regularization, the solution is obtained by the barrier method. However, the L(1) method often involves repeatedly solving large-dimensional matrix equations, which are computationally expensive. In this paper, the projection method is combined with the L(1) regularization method to reduce the computational cost. The L(1) problem is mainly solved in the coarse subspace. This paper also discusses the strategies of choosing parameters. Both simulation and experimental results of the L(1) regularization method were compared with the L(2) regularization method, indicating that the L(1) regularization method can improve the quality of image reconstruction and tolerate a relatively high level of noise in the measured voltages. Furthermore, the projected L(1) method can also effectively reduce the computational time without affecting the quality of reconstructed images.

  18. Immediate effects of neuromuscular joint facilitation intervention after anterior cruciate ligament reconstruction

    PubMed Central

    Wang, Lei

    2016-01-01

    [Purpose] The aim of this study was to examine the immediate effects of neuromuscular joint facilitation (NJF) on the functional activity level after rehabilitation of anterior cruciate ligament (ACL) reconstruction. [Subjects and Methods] Ten young subjects (8 males and 2 females) who underwent ACL reconstruction were included in the study. The subjects were divided into two groups, namely, knee joint extension muscle strength training (MST) group and knee joint extension outside rotation pattern of NJF group. Extension strength was measured in both groups before and after the experiment. Surface electromyography (sEMG) of the vastus medialis and vastus lateralis muscles and joint position error (JPE) test of the knee joint were also conducted. [Results] JPE test results and extension strength measurements in the NJF group were improved compared with those in the MST group. Moreover, the average discharge of the vastus medialis and vastus lateralis muscles on sEMG in the NJF group was significantly increased after MST and NJF treatments. [Conclusion] The obtained results suggest that NJF training in patients with ACL reconstruction can improve knee proprioception ability and muscle strength. PMID:27512270

  19. Immediate effects of neuromuscular joint facilitation intervention after anterior cruciate ligament reconstruction.

    PubMed

    Wang, Lei

    2016-07-01

    [Purpose] The aim of this study was to examine the immediate effects of neuromuscular joint facilitation (NJF) on the functional activity level after rehabilitation of anterior cruciate ligament (ACL) reconstruction. [Subjects and Methods] Ten young subjects (8 males and 2 females) who underwent ACL reconstruction were included in the study. The subjects were divided into two groups, namely, knee joint extension muscle strength training (MST) group and knee joint extension outside rotation pattern of NJF group. Extension strength was measured in both groups before and after the experiment. Surface electromyography (sEMG) of the vastus medialis and vastus lateralis muscles and joint position error (JPE) test of the knee joint were also conducted. [Results] JPE test results and extension strength measurements in the NJF group were improved compared with those in the MST group. Moreover, the average discharge of the vastus medialis and vastus lateralis muscles on sEMG in the NJF group was significantly increased after MST and NJF treatments. [Conclusion] The obtained results suggest that NJF training in patients with ACL reconstruction can improve knee proprioception ability and muscle strength. PMID:27512270

  20. Immediate effects of neuromuscular joint facilitation intervention after anterior cruciate ligament reconstruction.

    PubMed

    Wang, Lei

    2016-07-01

    [Purpose] The aim of this study was to examine the immediate effects of neuromuscular joint facilitation (NJF) on the functional activity level after rehabilitation of anterior cruciate ligament (ACL) reconstruction. [Subjects and Methods] Ten young subjects (8 males and 2 females) who underwent ACL reconstruction were included in the study. The subjects were divided into two groups, namely, knee joint extension muscle strength training (MST) group and knee joint extension outside rotation pattern of NJF group. Extension strength was measured in both groups before and after the experiment. Surface electromyography (sEMG) of the vastus medialis and vastus lateralis muscles and joint position error (JPE) test of the knee joint were also conducted. [Results] JPE test results and extension strength measurements in the NJF group were improved compared with those in the MST group. Moreover, the average discharge of the vastus medialis and vastus lateralis muscles on sEMG in the NJF group was significantly increased after MST and NJF treatments. [Conclusion] The obtained results suggest that NJF training in patients with ACL reconstruction can improve knee proprioception ability and muscle strength.

  1. Comparison and verification of the reconstruction method of the catheters for interstitial brachytherapy

    PubMed Central

    Zwierzchowski, Grzegorz; Skowronek, Janusz; Stefaniak, Patrycja; Dymnicka, Magdalena

    2009-01-01

    Purpose 1. Comparison and verification of accuracy of the implant reconstruction method based on images from IBU and CT. 2. Estimation of influence of the implant reconstruction method on dose disposition in selected reference points. Material and methods Paraffin-wax phantom with three catheters, central marker and control point were prepared. IBU unit were used for obtaining two series of images for reconstruction. The Earth magnetic field correction algorithm was used to correct S-shape distortions of the images. CT images (1 mm slice) were prepared. In the treatment planning system positions of 15 catheter points (MP, measure points), control point (CP) and central marker (CM) were reconstructed for each series of images. Distances between 15 catheter points and control point, and between catheter points and central marker were calculated. Results There were no statistically significant differences observed for IBU and CT based reconstructions for all orientations of the phantom (p > 0.05, U-Mann Whitney Test). There were no statistically significant differences observed between reconstruction based on IBU images with and without Earth magnetic field correction algorithm for phantom located perpendicular to the IBU table (p > 0.05, Wilcoxon Test). Statistically significant differences were observed only for images set with long axis of the phantom located parallel to the table (p < 0.05, Wilcoxon Test). There were no statistically significant differences observed for values doses in reference points for reconstruction based on IBU images and CT for all orientations of the phantom. Conclusions 1. Obtained results showed that IBU (radiographs based) reconstruction of the catheter placement is the reliable and accurate method for interstitial implants when reconstruction based on CT “catheter tracking” is not possible or not necessary. 2. The Earth magnetic field correction algorithm should be always use to correct S-shape distortions; reconstruction will be

  2. Anatomical reconstruction of the anterior cruciate ligament: a logical approach

    PubMed Central

    Gali, Julio Cesar

    2015-01-01

    We describe the surgical approach that we have used over the last years for anterior cruciate ligament (ACL) reconstruction, highlighting the importance of arthroscopic viewing through the anteromedial portal (AMP) and femoral tunnel drilling through an accessory anteromedial portal (AMP). The AMP allows direct view of the ACL femoral insertion site on the medial aspect of the lateral femoral condyle, does not require guides for anatomic femoral tunnel reaming, prevents an additional lateral incision in the distal third of the thigh (as would be unavoidable when the outside-in technique is used) and also can be used for double-bundle ACL reconstruction. PMID:26417571

  3. A Parallel Reconstructed Discontinuous Galerkin Method for the Compressible Flows on Aritrary Grids

    SciTech Connect

    Hong Luo; Amjad Ali; Robert Nourgaliev; Vincent A. Mousseau

    2010-01-01

    A reconstruction-based discontinuous Galerkin method is presented for the solution of the compressible Navier-Stokes equations on arbitrary grids. In this method, an in-cell reconstruction is used to obtain a higher-order polynomial representation of the underlying discontinuous Galerkin polynomial solution and an inter-cell reconstruction is used to obtain a continuous polynomial solution on the union of two neighboring, interface-sharing cells. The in-cell reconstruction is designed to enhance the accuracy of the discontinuous Galerkin method by increasing the order of the underlying polynomial solution. The inter-cell reconstruction is devised to remove an interface discontinuity of the solution and its derivatives and thus to provide a simple, accurate, consistent, and robust approximation to the viscous and heat fluxes in the Navier-Stokes equations. A parallel strategy is also devised for the resulting reconstruction discontinuous Galerkin method, which is based on domain partitioning and Single Program Multiple Data (SPMD) parallel programming model. The RDG method is used to compute a variety of compressible flow problems on arbitrary meshes to demonstrate its accuracy, efficiency, robustness, and versatility. The numerical results demonstrate that this RDG method is third-order accurate at a cost slightly higher than its underlying second-order DG method, at the same time providing a better performance than the third order DG method, in terms of both computing costs and storage requirements.

  4. Simultaneous denoising and reconstruction of 5-D seismic data via damped rank-reduction method

    NASA Astrophysics Data System (ADS)

    Chen, Yangkang; Zhang, Dong; Jin, Zhaoyu; Chen, Xiaohong; Zu, Shaohuan; Huang, Weilin; Gan, Shuwei

    2016-09-01

    The Cadzow rank-reduction method can be effectively utilized in simultaneously denoising and reconstructing 5-D seismic data that depend on four spatial dimensions. The classic version of Cadzow rank-reduction method arranges the 4-D spatial data into a level-four block Hankel/Toeplitz matrix and then applies truncated singular value decomposition (TSVD) for rank reduction. When the observed data are extremely noisy, which is often the feature of real seismic data, traditional TSVD cannot be adequate for attenuating the noise and reconstructing the signals. The reconstructed data tend to contain a significant amount of residual noise using the traditional TSVD method, which can be explained by the fact that the reconstructed data space is a mixture of both signal subspace and noise subspace. In order to better decompose the block Hankel matrix into signal and noise components, we introduced a damping operator into the traditional TSVD formula, which we call the damped rank-reduction method. The damped rank-reduction method can obtain a perfect reconstruction performance even when the observed data have extremely low signal-to-noise ratio. The feasibility of the improved 5-D seismic data reconstruction method was validated via both 5-D synthetic and field data examples. We presented comprehensive analysis of the data examples and obtained valuable experience and guidelines in better utilizing the proposed method in practice. Since the proposed method is convenient to implement and can achieve immediate improvement, we suggest its wide application in the industry.

  5. [Intra-articular reinforcement of a partially torn anterior cruciate ligament (ACL) using newly developed UHMWPE biomaterial in combination with Hexalon ACL/PCL screws: ex-vivo mechanical testing of an animal knee model].

    PubMed

    Fedorová, P; Srnec, R; Pěnčík, J; Dvořák, M; Krbec, M; Nečas, A

    2015-01-01

    PURPOSE OF THE STUDY Recent trends in the experimental surgical management of a partial anterior cruciate ligament (ACL) rupture in animals show repair of an ACL lesion using novel biomaterials both for biomechanical reinforcement of a partially unstable knee and as suitable scaffolds for bone marrow stem cell therapy in a partial ACL tear. The study deals with mechanical testing of the newly developed ultra-high-molecular-weight polyethylene (UHMWPE) biomaterial anchored to bone with Hexalon biodegradable ACL/PCL screws, as a new possibility of intra-articular reinforcement of a partial ACL tear. MATERIAL AND METHODS Two groups of ex vivo pig knee models were prepared and tested as follows: the model of an ACL tear stabilised with UHMWPE biomaterial using a Hexalon ACL/PCL screw (group 1; n = 10) and the model of an ACL tear stabilised with the traditional, and in veterinary medicine used, extracapsular technique involving a monofilament nylon fibre, a clamp and a Securos bone anchor (group 2; n = 11). The models were loaded at a standing angle of 100° and the maximum load (N) and shift (mm) values were recorded. RESULTS In group 1 the average maximal peak force was 167.6 ± 21.7 N and the shift was on average 19.0 ± 4.0 mm. In all 10 specimens, the maximum load made the UHMWPE implant break close to its fixation to the femur but the construct/fixation never failed at the site where the material was anchored to the bone. In group 2, the average maximal peak force was 207.3 ± 49.2 N and the shift was on average 24.1 ± 9.5 mm. The Securos stabilisation failed by pullout of the anchor from the femoral bone in nine out of 11 cases; the monofilament fibre ruptured in two cases. CONCLUSIONS It can be concluded that a UHMWPE substitute used in ex-vivo pig knee models has mechanical properties comparable with clinically used extracapsular Securos stabilisation and, because of its potential to carry stem cells and bioactive substances, it can meet the requirements for

  6. [Intra-articular reinforcement of a partially torn anterior cruciate ligament (ACL) using newly developed UHMWPE biomaterial in combination with Hexalon ACL/PCL screws: ex-vivo mechanical testing of an animal knee model].

    PubMed

    Fedorová, P; Srnec, R; Pěnčík, J; Dvořák, M; Krbec, M; Nečas, A

    2015-01-01

    PURPOSE OF THE STUDY Recent trends in the experimental surgical management of a partial anterior cruciate ligament (ACL) rupture in animals show repair of an ACL lesion using novel biomaterials both for biomechanical reinforcement of a partially unstable knee and as suitable scaffolds for bone marrow stem cell therapy in a partial ACL tear. The study deals with mechanical testing of the newly developed ultra-high-molecular-weight polyethylene (UHMWPE) biomaterial anchored to bone with Hexalon biodegradable ACL/PCL screws, as a new possibility of intra-articular reinforcement of a partial ACL tear. MATERIAL AND METHODS Two groups of ex vivo pig knee models were prepared and tested as follows: the model of an ACL tear stabilised with UHMWPE biomaterial using a Hexalon ACL/PCL screw (group 1; n = 10) and the model of an ACL tear stabilised with the traditional, and in veterinary medicine used, extracapsular technique involving a monofilament nylon fibre, a clamp and a Securos bone anchor (group 2; n = 11). The models were loaded at a standing angle of 100° and the maximum load (N) and shift (mm) values were recorded. RESULTS In group 1 the average maximal peak force was 167.6 ± 21.7 N and the shift was on average 19.0 ± 4.0 mm. In all 10 specimens, the maximum load made the UHMWPE implant break close to its fixation to the femur but the construct/fixation never failed at the site where the material was anchored to the bone. In group 2, the average maximal peak force was 207.3 ± 49.2 N and the shift was on average 24.1 ± 9.5 mm. The Securos stabilisation failed by pullout of the anchor from the femoral bone in nine out of 11 cases; the monofilament fibre ruptured in two cases. CONCLUSIONS It can be concluded that a UHMWPE substitute used in ex-vivo pig knee models has mechanical properties comparable with clinically used extracapsular Securos stabilisation and, because of its potential to carry stem cells and bioactive substances, it can meet the requirements for

  7. Iterative reconstruction methods in atmospheric tomography: FEWHA, Kaczmarz and Gradient-based algorithm

    NASA Astrophysics Data System (ADS)

    Ramlau, R.; Saxenhuber, D.; Yudytskiy, M.

    2014-07-01

    The problem of atmospheric tomography arises in ground-based telescope imaging with adaptive optics (AO), where one aims to compensate in real-time for the rapidly changing optical distortions in the atmosphere. Many of these systems depend on a sufficient reconstruction of the turbulence profiles in order to obtain a good correction. Due to steadily growing telescope sizes, there is a strong increase in the computational load for atmospheric reconstruction with current methods, first and foremost the MVM. In this paper we present and compare three novel iterative reconstruction methods. The first iterative approach is the Finite Element- Wavelet Hybrid Algorithm (FEWHA), which combines wavelet-based techniques and conjugate gradient schemes to efficiently and accurately tackle the problem of atmospheric reconstruction. The method is extremely fast, highly flexible and yields superior quality. Another novel iterative reconstruction algorithm is the three step approach which decouples the problem in the reconstruction of the incoming wavefronts, the reconstruction of the turbulent layers (atmospheric tomography) and the computation of the best mirror correction (fitting step). For the atmospheric tomography problem within the three step approach, the Kaczmarz algorithm and the Gradient-based method have been developed. We present a detailed comparison of our reconstructors both in terms of quality and speed performance in the context of a Multi-Object Adaptive Optics (MOAO) system for the E-ELT setting on OCTOPUS, the ESO end-to-end simulation tool.

  8. Effect of High-Grade Pre-operative Knee Laxity on Outcomes of Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Magnussen, Robert A.; Reinke, Emily; Huston, Laura J.; Group, MOON knee; Hewett, Timothy E.; Spindler, Kurt P.

    2015-01-01

    Objectives: Knee laxity in the setting of suspected anterior cruciate ligament (ACL) injury is frequently assessed through physical examination using the Lachman, pivot-shift, and anterior drawer tests. The degree of laxity noted on these examinations may influence treatment decisions and prognosis. We hypothesized that increased pre-operative knee laxity (Grade 3+ pivot-shift, Lachman > 10mm, or anterior drawer greater than 10mm) are associated with increased risk of revision ACL reconstruction and poorer patient-reported outcomes at two years post-operative. Methods: From an ongoing prospective cohort study, 1394 patients that underwent primary isolated ACL reconstruction within 3 months of injury with autograft tissue without medial collateral, lateral collateral, or posterior cruciate injury requiring treatment or prior contralateral ACL injury were identified. Demographic data, physical examination findings under anesthesia at the time of ACL reconstruction, information regarding meniscus status and treatment, and pre-operative and 2 year post-operative International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score Knee Related Quality of Life subscale (KOOS-QOL), and Marx activity scores were collected. Patients reported by the operating surgeons as having a Lachman or anterior drawer examination at least 10mm greater than the contralateral side were classified as having a high grade Lachman or anterior drawer respectively. Patients reported by the operating surgeon as having a 3+ pivot-shift were classified as having a high-grade pivot-shift. Patients demonstrating high-grade laxity on any of these examinations were classified as having high-grade pre-operative knee laxity. Multiple logistic regression modeling was used to evaluate whether having high-grade pre-operative laxity was associated with increased odds of undergoing revision ACL reconstruction within 2 years of the index procedure, controlling for patient age, sex

  9. A general few-projection method for tomographic reconstruction of samples consisting of several distinct materials

    SciTech Connect

    Myers, Glenn R.; Thomas, C. David L.; Clement, John G.; Paganin, David M.; Gureyev, Timur E.

    2010-01-11

    We present a method for tomographic reconstruction of objects containing several distinct materials, which is capable of accurately reconstructing a sample from vastly fewer angular projections than required by conventional algorithms. The algorithm is more general than many previous discrete tomography methods, as: (i) a priori knowledge of the exact number of materials is not required; (ii) the linear attenuation coefficient of each constituent material may assume a small range of a priori unknown values. We present reconstructions from an experimental x-ray computed tomography scan of cortical bone acquired at the SPring-8 synchrotron.

  10. Clinical outcomes of allograft versus autograft in anterior cruciate ligament reconstruction.

    PubMed

    Baer, Geoffrey S; Harner, Christopher D

    2007-10-01

    Anterior cruciate ligament (ACL) injuries are the most common complete ligamentous injury to the knee. The optimal graft should be able to reproduce the anatomy and biomechanics of the ACL, be incorporated rapidly with strong initial fixation, and cause low graft-site morbidity. This article reviews the literature comparing the clinical outcomes following allograft and autograft ACL reconstruction and examines current issues regarding graft choice.

  11. Clinical outcomes of allograft versus autograft in anterior cruciate ligament reconstruction.

    PubMed

    Baer, Geoffrey S; Harner, Christopher D

    2007-10-01

    Anterior cruciate ligament (ACL) injuries are the most common complete ligamentous injury to the knee. The optimal graft should be able to reproduce the anatomy and biomechanics of the ACL, be incorporated rapidly with strong initial fixation, and cause low graft-site morbidity. This article reviews the literature comparing the clinical outcomes following allograft and autograft ACL reconstruction and examines current issues regarding graft choice. PMID:17920959

  12. Reproducibility of the Structural Connectome Reconstruction across Diffusion Methods.

    PubMed

    Prčkovska, Vesna; Rodrigues, Paulo; Puigdellivol Sanchez, Ana; Ramos, Marc; Andorra, Magi; Martinez-Heras, Eloy; Falcon, Carles; Prats-Galino, Albert; Villoslada, Pablo

    2016-01-01

    Analysis of the structural connectomes can lead to powerful insights about the brain's organization and damage. However, the accuracy and reproducibility of constructing the structural connectome done with different acquisition and reconstruction techniques is not well defined. In this work, we evaluated the reproducibility of the structural connectome techniques by performing test-retest (same day) and longitudinal studies (after 1 month) as well as analyzing graph-based measures on the data acquired from 22 healthy volunteers (6 subjects were used for the longitudinal study). We compared connectivity matrices and tract reconstructions obtained with the most typical acquisition schemes used in clinical application: diffusion tensor imaging (DTI), high angular resolution diffusion imaging (HARDI), and diffusion spectrum imaging (DSI). We observed that all techniques showed high reproducibility in the test-retest analysis (correlation >.9). However, HARDI was the only technique with low variability (2%) in the longitudinal assessment (1-month interval). The intraclass coefficient analysis showed the highest reproducibility for the DTI connectome, however, with more sparse connections than HARDI and DSI. Qualitative (neuroanatomical) assessment of selected tracts confirmed the quantitative results showing that HARDI managed to detect most of the analyzed fiber groups and fanning fibers. In conclusion, we found that HARDI acquisition showed the most balanced trade-off between high reproducibility of the connectome, higher rate of path detection and of fanning fibers, and intermediate acquisition times (10-15 minutes), although at the cost of higher appearance of aberrant fibers. PMID:26464179

  13. Validation of plasma shape reconstruction by Cauchy condition surface method in KSTAR

    SciTech Connect

    Miyata, Y.; Suzuki, T.; Ide, S.; Hahn, S. H.; Chung, J.; Bak, J. G.; Ko, W. H.

    2014-03-15

    Cauchy Condition Surface (CCS) method is a numerical approach to reconstruct the plasma boundary and calculate the quantities related to plasma shape using the magnetic diagnostics in real time. It has been applied to the KSTAR plasma in order to establish the plasma shape reconstruction with the high elongation of plasma shape and the large effect of eddy currents flowing in the tokamak structures for the first time. For applying the CCS calculation to the KSTAR plasma, the effects by the eddy currents and the ferromagnetic materials on the plasma shape reconstruction are studied. The CCS calculation includes the effect of eddy currents and excludes the magnetic diagnostics, which is expected to be influenced largely by ferromagnetic materials. Calculations have been performed to validate the plasma shape reconstruction in 2012 KSTAR experimental campaign. Comparison between the CCS calculation and non-magnetic measurements revealed that the CCS calculation can reconstruct the accurate plasma shape even with a small I{sub P}.

  14. MR-guided dynamic PET reconstruction with the kernel method and spectral temporal basis functions.

    PubMed

    Novosad, Philip; Reader, Andrew J

    2016-06-21

    Recent advances in dynamic positron emission tomography (PET) reconstruction have demonstrated that it is possible to achieve markedly improved end-point kinetic parameter maps by incorporating a temporal model of the radiotracer directly into the reconstruction algorithm. In this work we have developed a highly constrained, fully dynamic PET reconstruction algorithm incorporating both spectral analysis temporal basis functions and spatial basis functions derived from the kernel method applied to a co-registered T1-weighted magnetic resonance (MR) image. The dynamic PET image is modelled as a linear combination of spatial and temporal basis functions, and a maximum likelihood estimate for the coefficients can be found using the expectation-maximization (EM) algorithm. Following reconstruction, kinetic fitting using any temporal model of interest can be applied. Based on a BrainWeb T1-weighted MR phantom, we performed a realistic dynamic [(18)F]FDG simulation study with two noise levels, and investigated the quantitative performance of the proposed reconstruction algorithm, comparing it with reconstructions incorporating either spectral analysis temporal basis functions alone or kernel spatial basis functions alone, as well as with conventional frame-independent reconstruction. Compared to the other reconstruction algorithms, the proposed algorithm achieved superior performance, offering a decrease in spatially averaged pixel-level root-mean-square-error on post-reconstruction kinetic parametric maps in the grey/white matter, as well as in the tumours when they were present on the co-registered MR image. When the tumours were not visible in the MR image, reconstruction with the proposed algorithm performed similarly to reconstruction with spectral temporal basis functions and was superior to both conventional frame-independent reconstruction and frame-independent reconstruction with kernel spatial basis functions. Furthermore, we demonstrate that a joint spectral

  15. MR-guided dynamic PET reconstruction with the kernel method and spectral temporal basis functions

    NASA Astrophysics Data System (ADS)

    Novosad, Philip; Reader, Andrew J.

    2016-06-01

    Recent advances in dynamic positron emission tomography (PET) reconstruction have demonstrated that it is possible to achieve markedly improved end-point kinetic parameter maps by incorporating a temporal model of the radiotracer directly into the reconstruction algorithm. In this work we have developed a highly constrained, fully dynamic PET reconstruction algorithm incorporating both spectral analysis temporal basis functions and spatial basis functions derived from the kernel method applied to a co-registered T1-weighted magnetic resonance (MR) image. The dynamic PET image is modelled as a linear combination of spatial and temporal basis functions, and a maximum likelihood estimate for the coefficients can be found using the expectation-maximization (EM) algorithm. Following reconstruction, kinetic fitting using any temporal model of interest can be applied. Based on a BrainWeb T1-weighted MR phantom, we performed a realistic dynamic [18F]FDG simulation study with two noise levels, and investigated the quantitative performance of the proposed reconstruction algorithm, comparing it with reconstructions incorporating either spectral analysis temporal basis functions alone or kernel spatial basis functions alone, as well as with conventional frame-independent reconstruction. Compared to the other reconstruction algorithms, the proposed algorithm achieved superior performance, offering a decrease in spatially averaged pixel-level root-mean-square-error on post-reconstruction kinetic parametric maps in the grey/white matter, as well as in the tumours when they were present on the co-registered MR image. When the tumours were not visible in the MR image, reconstruction with the proposed algorithm performed similarly to reconstruction with spectral temporal basis functions and was superior to both conventional frame-independent reconstruction and frame-independent reconstruction with kernel spatial basis functions. Furthermore, we demonstrate that a joint spectral

  16. Adaptive region of interest method for analytical micro-CT reconstruction.

    PubMed

    Yang, Wanneng; Xu, Xiaochun; Bi, Kun; Zeng, Shaoqun; Liu, Qian; Chen, Shangbin

    2011-01-01

    The real-time imaging is important in automatic successive inspection with micro-computerized tomography (micro-CT). Generally, the size of the detector is chosen according to the most probable size of the measured object to acquire all the projection data. Given enough imaging area and imaging resolution of X-ray detector, the detector is larger than specimen projection area, which results in redundant data in the Sinogram. The process of real-time micro-CT is computation-intensive because of the large amounts of source and destination data. The speed of the reconstruction algorithm can't always meet the requirements of real-time applications. A preprocessing method called adaptive region of interest (AROI), which detects the object's boundaries automatically to focus the active Sinogram regions, is introduced into the analytical reconstruction algorithm in this paper. The AROI method reduces the volume of the reconstructing data and thus directly accelerates the reconstruction process. It has been further shown that image quality is not compromised when applying AROI, while the reconstruction speed is increased as the square of the ratio of the sizes of the detector and the specimen slice. In practice, the conch reconstruction experiment indicated that the process is accelerated by 5.2 times with AROI and the imaging quality is not degraded. Therefore, the AROI method improves the speed of analytical micro-CT reconstruction significantly.

  17. Adaptive region of interest method for analytical micro-CT reconstruction.

    PubMed

    Yang, Wanneng; Xu, Xiaochun; Bi, Kun; Zeng, Shaoqun; Liu, Qian; Chen, Shangbin

    2011-01-01

    The real-time imaging is important in automatic successive inspection with micro-computerized tomography (micro-CT). Generally, the size of the detector is chosen according to the most probable size of the measured object to acquire all the projection data. Given enough imaging area and imaging resolution of X-ray detector, the detector is larger than specimen projection area, which results in redundant data in the Sinogram. The process of real-time micro-CT is computation-intensive because of the large amounts of source and destination data. The speed of the reconstruction algorithm can't always meet the requirements of real-time applications. A preprocessing method called adaptive region of interest (AROI), which detects the object's boundaries automatically to focus the active Sinogram regions, is introduced into the analytical reconstruction algorithm in this paper. The AROI method reduces the volume of the reconstructing data and thus directly accelerates the reconstruction process. It has been further shown that image quality is not compromised when applying AROI, while the reconstruction speed is increased as the square of the ratio of the sizes of the detector and the specimen slice. In practice, the conch reconstruction experiment indicated that the process is accelerated by 5.2 times with AROI and the imaging quality is not degraded. Therefore, the AROI method improves the speed of analytical micro-CT reconstruction significantly. PMID:21422587

  18. High tibial osteotomy in the ACL-deficient knee with medial compartment osteoarthritis.

    PubMed

    Herman, Benjamin V; Giffin, J Robert

    2016-09-01

    High tibial osteotomy (HTO) has traditionally been used to treat varus gonarthrosis in younger, active patients. Varus malalignment increases the risk of progression of medial compartment osteoarthritis and an HTO can be performed to realign the mechanical axis of the lower limb towards the lateral compartment, thereby decreasing contact pressures in the medial compartment. Anterior cruciate ligament (ACL) insufficiency may lead to post-traumatic arthritis due to altered joint loading and associated injuries to the menisci and articular cartilage. Understanding the importance of posterior tibial slope and its role in sagittal knee stability has led to the development of biplane osteotomies designed to flatten the posterior tibial slope in the ACL deficient knee. Altering the alignment in both the sagittal and coronal planes helps improve stability as well as alter the load in the medial compartment. Detailed history, physical exam and radiographic analysis guide treatment decisions in this high demand patient population. Lateral closing wedge (LCW) and medial opening wedge (MOW) HTOs have been performed and their potential advantages and disadvantages have been well described. Given the triangular shape of the proximal tibia, it is imperative that the surgeon pay close attention to the geometry of the osteotomy "gap" when performing MOW HTO to avoid inadvertently increasing the posterior tibial slope. Simultaneous ACL reconstruction may require technique modifications depending on the type of HTO and ACL graft chosen. With appropriate patient selection and good surgical technique, it is reasonable to expect patients to return to activities of daily living and recreational sports without debilitating pain or instability. PMID:27358200

  19. Reconstruction of vibroacoustic responses of a highly nonspherical structure using Helmholtz equation least-squares method.

    PubMed

    Lu, Huancai; Wu, Sean F

    2009-03-01

    The vibroacoustic responses of a highly nonspherical vibrating object are reconstructed using Helmholtz equation least-squares (HELS) method. The objectives of this study are to examine the accuracy of reconstruction and the impacts of various parameters involved in reconstruction using HELS. The test object is a simply supported and baffled thin plate. The reason for selecting this object is that it represents a class of structures that cannot be exactly described by the spherical Hankel functions and spherical harmonics, which are taken as the basis functions in the HELS formulation, yet the analytic solutions to vibroacoustic responses of a baffled plate are readily available so the accuracy of reconstruction can be checked accurately. The input field acoustic pressures for reconstruction are generated by the Rayleigh integral. The reconstructed normal surface velocities are validated against the benchmark values, and the out-of-plane vibration patterns at several natural frequencies are compared with the natural modes of a simply supported plate. The impacts of various parameters such as number of measurement points, measurement distance, location of the origin of the coordinate system, microphone spacing, and ratio of measurement aperture size to the area of source surface of reconstruction on the resultant accuracy of reconstruction are examined. PMID:19275312

  20. Single-legged hop tests as predictors of self-reported knee function in non-operatively treated individuals with ACL injury

    PubMed Central

    Grindem, Hege; Logerstedt, David; Eitzen, Ingrid; Moksnes, Håvard; Axe, Michael J.; Snyder-Mackler, Lynn; Engebretsen, Lars; Risberg, May Arna

    2013-01-01

    Background Previous studies have found significant predictors for functional outcome after ACL reconstruction, however, studies examining predictors for functional outcome in non-operatively treated individuals are lacking. Hypothesis Single-legged hop tests predict self-reported knee function (IKDC2000) in non-operatively treated ACL-injured individuals 1 year after baseline testing. Study Design Cohort study (prognosis); Level of evidence, 2. Methods Ninety-one non-operatively treated subjects with an ACL injury were tested using 4 one-legged hop tests on average 74 ± 30 days after injury in a prospective cohort study. Eighty-one subjects (89 %) completed the IKDC2000 1 year later. Subjects with an IKDC2000 score equal to or higher than the age- and gender-specific 15th percentile score from previously published data on an uninjured population were classified as having self-reported function within normal ranges. Logistic regression analyses were performed to identify predictors of self-reported knee function. The Area Under the Curve (AUC) from Receiver Operating Characteristic curves was used as a measure of discriminative accuracy. Optimal limb symmetry index (LSI) cutoff for the best single-legged hop test was defined as the LSI with the highest product of sensitivity and specificity. Results Single hop for distance symmetry indexes predicted self-reported knee function at the 1-year follow-up (p=0.036). Combinations of any 2 hop tests (AUC=0.64–0.71) did not give a higher discriminative accuracy than the single hop alone (AUC=0.71). A cutoff of 88 % (LSI) for the single hop revealed a sensitivity of 71.4 % and a specificity of 71.7 %. Conclusion The single hop for distance (LSI) significantly predicted self-reported knee function after 1 year in non-operatively treated ACL-injured subjects. Combinations of 2 single-legged hop tests did not lead to higher discriminative accuracy than the single hop alone. PMID:21828364

  1. Reconstruction Method for Optical Tomography Based on the Linearized Bregman Iteration with Sparse Regularization.

    PubMed

    Leng, Chengcai; Yu, Dongdong; Zhang, Shuang; An, Yu; Hu, Yifang

    2015-01-01

    Optical molecular imaging is a promising technique and has been widely used in physiology, and pathology at cellular and molecular levels, which includes different modalities such as bioluminescence tomography, fluorescence molecular tomography and Cerenkov luminescence tomography. The inverse problem is ill-posed for the above modalities, which cause a nonunique solution. In this paper, we propose an effective reconstruction method based on the linearized Bregman iterative algorithm with sparse regularization (LBSR) for reconstruction. Considering the sparsity characteristics of the reconstructed sources, the sparsity can be regarded as a kind of a priori information and sparse regularization is incorporated, which can accurately locate the position of the source. The linearized Bregman iteration method is exploited to minimize the sparse regularization problem so as to further achieve fast and accurate reconstruction results. Experimental results in a numerical simulation and in vivo mouse demonstrate the effectiveness and potential of the proposed method. PMID:26421055

  2. Apparatus And Method For Reconstructing Data Using Cross-Parity Stripes On Storage Media

    DOEpatents

    Hughes, James Prescott

    2003-06-17

    An apparatus and method for reconstructing missing data using cross-parity stripes on a storage medium is provided. The apparatus and method may operate on data symbols having sizes greater than a data bit. The apparatus and method makes use of a plurality of parity stripes for reconstructing missing data stripes. The parity symbol values in the parity stripes are used as a basis for determining the value of the missing data symbol in a data stripe. A correction matrix is shifted along the data stripes, correcting missing data symbols as it is shifted. The correction is performed from the outside data stripes towards the inner data stripes to thereby use previously reconstructed data symbols to reconstruct other missing data symbols.

  3. The Correlation of Tunnel Position, Orientation and Tunnel Enlargement in Outside-in Single-Bundle Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Ko, Young Won; Rhee, Seung Jun; Kim, In Woo

    2015-01-01

    Purpose Tunnel widening after anterior cruciate ligament (ACL) reconstruction is a frequently described phenomenon. The possible etiology is multi-factorial with some mechanical and biological factors. Among those, we intended to determine the relation between the location and orientation of the femoral tunnel and the femoral tunnel enlargement after outside-in single-bundle ACL reconstruction. Materials and Methods A retrospective study including 42 patients who received single-bundle ACL reconstruction with the outside-in technique was conducted. Femoral and tibial tunnel locations were evaluated with the quadrant method and bird's-eye view using volume-rendering computed tomography. The angle and diameter of bone tunnel and the degree of tunnel enlargement were evaluated using standard radiographs. Results The degree of femoral tunnel enlargements were 42% and 36% on the anteroposterior (AP) and lateral radiographs, respectively, and the degree of tibial tunnel enlargements were 22% and 23%, respectively. Shallower location of the femoral tunnel was significantly correlated with greater femoral tunnel enlargement on the AP radiograph (r=0.998, p=0.004) and the lateral radiograph (r=0.72, p=0.005) as was the higher location of the femoral tunnel on the AP radiograph (r=-0.47, p=0.01) and the lateral radiograph (r=-0.36, p=0.009) at 12 months after surgery. Conclusions This study revealed that more anterior and higher location and more horizontal orientation of the femoral tunnel in coronal plane could result in widening of the femoral tunnel in outside-in single-bundle ACL reconstruction. PMID:26672479

  4. Modified Method of Increasing of Reconstruction Quality of Diffractive Optical Elements Displayed with LC SLM

    NASA Astrophysics Data System (ADS)

    Krasnov, V. V.; Cheremkhin, P. A.; Erkin, I. Yu.; Evtikhiev, N. N.; Starikov, R. S.; Starikov, S. N.

    Modified method of increasing of reconstruction quality of diffractive optical elements (DOE) displayed with liquid crystal (LC) spatial light modulators (SLM) is presented. Method is based on optimization of DOE synthesized with conventional method by application of direct search with random trajectory method while taking into account LC SLM phase fluctuations. Reduction of synthesis error up to 88% is achieved.

  5. Gait patterns before and after anterior cruciate ligament reconstruction.

    PubMed

    Knoll, Zsolt; Kocsis, László; Kiss, Rita M

    2004-01-01

    The aim of this study is to determine how selected gait parameters may change as a result of anterior cruciate ligament (ACL) deficiency and following ACL reconstruction. The study was performed on 25 ACL-deficient subjects prior to and 6 weeks, 4 months, 8 months and 12 months after ACL reconstructive surgery by the bone-patellar tendon-bone technique. Gait analysis was performed using the zebris three-dimensional ultrasound-based system with surface electromyograph (zebris Medizintechnik GmbH, Germany). Kinematic data were recorded for the lower limb. The muscles examined include vastus lateralis and medialis, biceps femoris and adductor longus. The results obtained from the injured subjects were compared with those of 51 individuals without ACL damage. The acute ACL-deficient patients exhibited a quadriceps avoidance pattern prior to and 6 weeks after surgery. The quadriceps avoidance phenomenon does not develop in chronic ACL-deficient patients. In the individuals operated on, the spatial-temporal parameters and the knee angle had already regained a normal pattern for the ACL-deficient limb during gait 4 months after surgery. However, the relative ACL movement parameter-which describes the tibial translation into the direction of ACL-and the EMG traces show no significant statistical difference compared with the values of healthy control group just 8 months after surgery. The results suggest that: (1) development of a quadriceps avoidance pattern is less common than previously reported, (2) anterior cruciate ligament deficiency and reconstruction significantly alter the lower extremity gait pattern, (3) the gait parameters shift towards the normal value pattern, and (4) the re-establishment of pre-injury gait patterns--including the normal biphase of muscles--takes at least 8 months to occur.

  6. A method of 3D reconstruction from multiple views based on graph theoretic segmentation

    NASA Astrophysics Data System (ADS)

    Li, Yi; Hong, Hanyu; Zhang, Xiuhua; Bai, Haoyu

    2013-10-01

    During the process of three-dimensional vision inspection for products, the target objects under the complex background are usually immovable. So the desired three-dimensional reconstruction results can not be able to be obtained because of achieving the targets, which is difficult to be extracted from the images under the complicated and diverse background. Aiming at the problem, a method of three-dimensional reconstruction based on the graph theoretic segmentation and multiple views is proposed in this paper. Firstly, the target objects are segmented from obtained multi-view images by the method based on graph theoretic segmentation and the parameters of all cameras arranged in a linear way are gained by the method of Zhengyou Zhang calibration. Then, combined with Harris corner detection and Difference of Gaussian detection algorithm, the feature points of the images are detected. At last, after matching feature points by the triangle method, the surface of the object is reconstructed by the method of Poisson surface reconstruction. The reconstruction experimental results show that the proposed algorithm segments the target objects in the complex scene accurately and steadily. What's more, the algorithm based on the graph theoretic segmentation solves the problem of object extraction in the complex scene, and the static object surface is reconstructed precisely. The proposed algorithm also provides the crucial technology for the three-dimensional vision inspection and other practical applications.

  7. Magnetic Field Configuration Models and Reconstruction Methods for Interplanetary Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Al-Haddad, N.; Nieves-Chinchilla, T.; Savani, N. P.; Möstl, C.; Marubashi, K.; Hidalgo, M. A.; Roussev, I. I.; Poedts, S.; Farrugia, C. J.

    2013-05-01

    This study aims to provide a reference for different magnetic field models and reconstruction methods for interplanetary coronal mass ejections (ICMEs). To understand the differences in the outputs of these models and codes, we analyzed 59 events from the Coordinated Data Analysis Workshop (CDAW) list, using four different magnetic field models and reconstruction techniques; force-free fitting, magnetostatic reconstruction using a numerical solution to the Grad-Shafranov equation, fitting to a self-similarly expanding cylindrical configuration and elliptical, non-force-free fitting. The resulting parameters of the reconstructions for the 59 events are compared statistically and in selected case studies. The ability of a method to fit or reconstruct an event is found to vary greatly; this depends on whether the event is a magnetic cloud or not. We find that the magnitude of the axial field is relatively consistent across models, but that the axis orientation of the ejecta is not. We also find that there are a few cases with different signs of the magnetic helicity for the same event when we leave the boundaries free to vary, which illustrates that this simplest of parameters is not necessarily always clearly constrained by fitting and reconstruction models. Finally, we examine three unique cases in depth to provide a comprehensive idea of the different aspects of how the fitting and reconstruction codes work.

  8. Compensation for acoustic heterogeneities in photoacoustic computed tomography using a variable temporal data truncation reconstruction method

    NASA Astrophysics Data System (ADS)

    Poudel, Joemini; Matthews, Thomas P.; Anastasio, Mark A.; Wang, Lihong V.

    2016-03-01

    Photoacoustic computed tomography (PACT) is an emerging computed imaging modality that exploits optical contrast and ultrasonic detection principles to form images of the absorbed optical energy density within tissue. If the object possesses spatially variant acoustic properties that are unaccounted for by the reconstruction algorithm, the estimated image can contain distortions. While reconstruction algorithms have recently been developed for compensating for this effect, they generally require the objects acoustic properties to be known a priori. To circumvent the need for detailed information regarding an objects acoustic properties, we have previously proposed a half-time reconstruction method for PACT. A half-time reconstruction method estimates the PACT image from a data set that has been temporally truncated to exclude the data components that have been strongly aberrated. In this approach, the degree of temporal truncation is the same for all measurements. However, this strategy can be improved upon it when the approximate sizes and locations of strongly heterogeneous structures such as gas voids or bones are known. In this work, we investigate PACT reconstruction algorithms that are based on a variable temporal data truncation (VTDT) approach that represents a generalization of the half-time reconstruction approach. In the VTDT approach, the degree of temporal truncation for each measurement is determined by the distance between the corresponding transducer location and the nearest known bone or gas void location. Reconstructed images from a numerical phantom is employed to demonstrate the feasibility and effectiveness of the approach.

  9. Landing on an Unstable Surface Decreases ACL Biomechanical Risk Factors

    PubMed Central

    Shultz, Rebecca; Malone, Maria; Swank, Kat; Andrews, Rob; Braun, Hillary J.; Slider, Amy; Dragoo, Jason L.

    2013-01-01

    Objectives: Quadriceps dominant athletes are at a higher risk for anterior cruciate ligament (ACL) injuries because they lack sufficient hamstring activation resulting in a higher Quadricips: hamstring ratio. Muscular co-contraction (low Q:H) is needed to protect the intra-articular structures of the knee. Exercises that promote co-contraction and proprioception have been shown to reduce quadriceps dominance, enhance knee stability and alter neuromuscular firing patterns. The purpose of this investigation was to examine whether landing on an unstable surface (Bosu Ball) induced a greater amount of co-contraction at the knee compared to a stable surface. Methods: Thirty-one Division I NCAA female athletes performed 3 single leg drop jumps per leg on 2 surfaces. Subjects dropped from a 30 cm step first onto the floor (stable surface), and onto a Bosu ball (unstable surface). Each landing was held for a minimum of 2 seconds. Subjects were familiar with Bosu ball training. Muscle activity of the lateral hamstring and vastus lateralis were used to estimate peak hamstring activity and the Quadriceps:Hamstring (Q:H) co-contraction ratio at the time of peak quadriceps activity. Kinematic data were also collected (Vicon) and used to evaluate the following peak measurements: knee flexion angle, hip flexion angle, and trunk flexion and sway angles (Visual3D). All variables were assessed between the time of landing and the end of deceleration. A 1-level ANOVA was used to test for significant differences across the sports in for each variable of interest. Significance was set at p<0.05. Results: Max co-contraction (Q:H) was significantly reduced when athletes landed on an unstable surface (45% lower, p<0.01 Table 1, Figure 1A) compared to the stable surface. Peak hamstring activity was higher when landing on an unstable surface (15% higher, p=0.05, Table 1) compared to a stable surface. Peak knee flexion angles were 21% greater when athletes landed on a stable surface compared

  10. A new skin flap method for total auricular reconstruction in microtia patients with a reconstructed ear canal: extended scalp and extended mastoid postauricular skin flaps.

    PubMed

    Hwang, Euna; Kim, Young Soo; Chung, Seum

    2014-06-01

    Before visiting a plastic surgeon, some microtia patients may undergo canaloplasty for hearing improvement. In such cases, scarred tissues and the reconstructed external auditory canal in the postauricular area may cause a significant limitation in using the posterior auricular skin flap for ear reconstruction. In this article, we present a new method for auricular reconstruction in microtia patients with previous canaloplasty. By dividing a postauricular skin flap into an upper scalp extended skin flap and a lower mastoid extended skin flap at the level of a reconstructed external auditory canal, the entire anterior surface of the auricular framework can be covered with the two extended postauricular skin flaps. The reconstructed ear shows good color match and texture, with the entire anterior surface of the reconstructed ear being resurfaced with the skin flaps. Clinical question/level of evidence; therapeutic level IV.

  11. A Wearable Neuromuscular Device Reduces ACL Injury Risk in Female Soccer Athletes

    PubMed Central

    Decker, Michael John; Shaw, Matthew; Maddan, Casey; Campbell, Julie; Davidson, Bradley

    2016-01-01

    Objectives: Female soccer athletes have a three-fold greater risk of sustaining an ACL injury compared with their male counterparts yet only 1 in 5 teams engage in ACL risk reduction programs due to several participation barriers. The purpose of this study was to determine the effects of a wearable neuromuscular (WNM) device on postural control, performance and ACL injury risk in female soccer athletes. Methods: Seventy-nine elite youth and collegiate female soccer athletes (age range: 12-25 y) trained with a WNM device that applied bi-lateral, topical pressure to the medial quadriceps and hamstrings muscles (Topical Gear, Austin, TX). The athletes performed 7-9 weeks of pre-season training with the WNM device consisting of strength and conditioning exercises and on-field team practices (46-64 total hours of exposure). Postural control was measured in 15 athletes with and without the WNM device before and after the training program; and performance was measured in 25 athletes without the WNM device before and after the training program. Postural control was determined from a single-leg landing on a force plate from a horizontal distance normalized to leg length. The athletes were instructed to gain their balance as fast as possible upon landing and remain balanced for 5 seconds. The peak ground reaction forces (GRF) and the medial-lateral, anterior-posterior and net center of pressure (COP) velocities and displacement ranges were calculated during 2 seconds of single-leg stance. Performance measures including speed, power and endurance were measured from the 40 yard dash, vertical jump for height and the Beep test, respectively. A two-way repeated measures ANOVA and post-hoc comparisons were used to compare the postural variables; and t-tests were used to compare the performance tests (p=.05). ACL injury rates, the absolute risk reduction (ARR) and the number needed to treat (NNT) to prevent one ACL injury were calculated between the WNM intervention group and 11

  12. Multigrid iterative method with adaptive spatial support for computed tomography reconstruction from few-view data

    NASA Astrophysics Data System (ADS)

    Lee, Ping-Chang

    2014-03-01

    Computed tomography (CT) plays a key role in modern medical system, whether it be for diagnosis or therapy. As an increased risk of cancer development is associated with exposure to radiation, reducing radiation exposure in CT becomes an essential issue. Based on the compressive sensing (CS) theory, iterative based method with total variation (TV) minimization is proven to be a powerful framework for few-view tomographic image reconstruction. Multigrid method is an iterative method for solving both linear and nonlinear systems, especially when the system contains a huge number of components. In medical imaging, image background is often defined by zero intensity, thus attaining spatial support of the image, which is helpful for iterative reconstruction. In the proposed method, the image support is not considered as a priori knowledge. Rather, it evolves during the reconstruction process. Based on the CS framework, we proposed a multigrid method with adaptive spatial support constraint. The simultaneous algebraic reconstruction (SART) with TV minimization is implemented for comparison purpose. The numerical result shows: 1. Multigrid method has better performance while less than 60 views of projection data were used, 2. Spatial support highly improves the CS reconstruction, and 3. When few views of projection data were measured, our method performs better than the SART+TV method with spatial support constraint.

  13. Reconstruction of electrical impedance tomography (EIT) images based on the expectation maximum (EM) method.

    PubMed

    Wang, Qi; Wang, Huaxiang; Cui, Ziqiang; Yang, Chengyi

    2012-11-01

    Electrical impedance tomography (EIT) calculates the internal conductivity distribution within a body using electrical contact measurements. The image reconstruction for EIT is an inverse problem, which is both non-linear and ill-posed. The traditional regularization method cannot avoid introducing negative values in the solution. The negativity of the solution produces artifacts in reconstructed images in presence of noise. A statistical method, namely, the expectation maximization (EM) method, is used to solve the inverse problem for EIT in this paper. The mathematical model of EIT is transformed to the non-negatively constrained likelihood minimization problem. The solution is obtained by the gradient projection-reduced Newton (GPRN) iteration method. This paper also discusses the strategies of choosing parameters. Simulation and experimental results indicate that the reconstructed images with higher quality can be obtained by the EM method, compared with the traditional Tikhonov and conjugate gradient (CG) methods, even with non-negative processing.

  14. The Results of All-Inside Meniscus Repair Using the Viper Repair System Simultaneously with Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Kang, Hong Je; Kim, Kwang Mee; Cho, Hang Hwan; Espinosa, Johnsel C.

    2015-01-01

    Background Meniscus tears are commonly associated with anterior cruciate ligament (ACL) ruptures. It is essential to repair meniscal tears as much as possible to prevent early osteoarthritis and to gain additional stability in the knee joint. We evaluated the results of arthroscopic all-inside repair using the Meniscal Viper Repair System (Arthrex) on meniscus tears simultaneously with ACL reconstruction. Methods Nineteen out of 22 patients who were treated with arthroscopic all-inside repair using the Meniscal Viper Repair System for meniscus tear associated with ACL rupture were evaluated. ACL reconstructions were performed at the same period. The mean follow-up period was 16.5 months (range, 12 to 24 months). The clinical results of the meniscus repair were evaluated by symptoms (such as catching or locking), tenderness, effusion, range of motion limitation, and the McMurray test. Clinical success was defined by negative results in all five categories. The Hospital for Special Surgery (HSS) score was evaluated. Objective results were evaluated with secondary look arthroscopy or magnetic resonance imaging (MRI). The MRI results were categorized as completely repaired, incompletely repaired, and failure by Henning's classification. The results of second-look arthroscopy were evaluated with the criteria of meniscal healing. Results The clinical success rate was 95.4% and the HSS scores were 93.9 ± 5.4 at the final follow-up. According to Henning's classification, 15 out of 18 cases showed complete healing (83.3%) and two cases (11.1%) showed incomplete healing. Seventeen out of 18 cases that underwent second-look arthroscopy showed complete healing (94.4%) according to the criteria of meniscal healing. Only one case showed failure and the failure was due to a re-rupture at the sutured area. Complications of ACL reconstruction or meniscus repair were not present. Conclusions The results demonstrate that arthroscopic all-inside repair using the Meniscal Viper Repair

  15. A model-based reconstruction method for 3-D rotational coronary angiography

    PubMed Central

    Xie, Lizhe; Hu, Yining; Nunes, Jean-Claude; Bellanger, Jean-Jacques; Bedossa, Marc; Luo, Limin; Toumoulin, Christine

    2010-01-01

    This paper presents a model-based reconstruction method of the coronary tree from a few number of projections in rotational angiography imaging. The reconstruction relies on projections acquired at a same cardiac phase and an energy function minimization that aims to lead the deformation of the 3D model to fit projection data whereas preserving coherence both in time and space. Some preliminary results are provided on simulated rotational angiograms. PMID:21096600

  16. DETECTORS AND EXPERIMENTAL METHODS: Decay vertex reconstruction and 3-dimensional lifetime determination at BESIII

    NASA Astrophysics Data System (ADS)

    Xu, Min; He, Kang-Lin; Zhang, Zi-Ping; Wang, Yi-Fang; Bian, Jian-Ming; Cao, Guo-Fu; Cao, Xue-Xiang; Chen, Shen-Jian; Deng, Zi-Yan; Fu, Cheng-Dong; Gao, Yuan-Ning; Han, Lei; Han, Shao-Qing; He, Miao; Hu, Ji-Feng; Hu, Xiao-Wei; Huang, Bin; Huang, Xing-Tao; Jia, Lu-Kui; Ji, Xiao-Bin; Li, Hai-Bo; Li, Wei-Dong; Liang, Yu-Tie; Liu, Chun-Xiu; Liu, Huai-Min; Liu, Ying; Liu, Yong; Luo, Tao; Lü, Qi-Wen; Ma, Qiu-Mei; Ma, Xiang; Mao, Ya-Jun; Mao, Ze-Pu; Mo, Xiao-Hu; Ning, Fei-Peng; Ping, Rong-Gang; Qiu, Jin-Fa; Song, Wen-Bo; Sun, Sheng-Sen; Sun, Xiao-Dong; Sun, Yong-Zhao; Tian, Hao-Lai; Wang, Ji-Ke; Wang, Liang-Liang; Wen, Shuo-Pin; Wu, Ling-Hui; Wu, Zhi; Xie, Yu-Guang; Yan, Jie; Yan, Liang; Yao, Jian; Yuan, Chang-Zheng; Yuan, Ye; Zhang, Chang-Chun; Zhang, Jian-Yong; Zhang, Lei; Zhang, Xue-Yao; Zhang, Yao; Zheng, Yang-Heng; Zhu, Yong-Sheng; Zou, Jia-Heng

    2009-06-01

    This paper focuses mainly on the vertex reconstruction of resonance particles with a relatively long lifetime such as K0S, Λ, as well as on lifetime measurements using a 3-dimensional fit. The kinematic constraints between the production and decay vertices and the decay vertex fitting algorithm based on the least squares method are both presented. Reconstruction efficiencies including experimental resolutions are discussed. The results and systematic errors are calculated based on a Monte Carlo simulation.

  17. Novel l2,1-norm optimization method for fluorescence molecular tomography reconstruction

    PubMed Central

    Jiang, Shixin; Liu, Jie; An, Yu; Zhang, Guanglei; Ye, Jinzuo; Mao, Yamin; He, Kunshan; Chi, Chongwei; Tian, Jie

    2016-01-01

    Fluorescence molecular tomography (FMT) is a promising tomographic method in preclinical research, which enables noninvasive real-time three-dimensional (3-D) visualization for in vivo studies. The ill-posedness of the FMT reconstruction problem is one of the many challenges in the studies of FMT. In this paper, we propose a l2,1-norm optimization method using a priori information, mainly the structured sparsity of the fluorescent regions for FMT reconstruction. Compared to standard sparsity methods, the structured sparsity methods are often superior in reconstruction accuracy since the structured sparsity utilizes correlations or structures of the reconstructed image. To solve the problem effectively, the Nesterov’s method was used to accelerate the computation. To evaluate the performance of the proposed l2,1-norm method, numerical phantom experiments and in vivo mouse experiments are conducted. The results show that the proposed method not only achieves accurate and desirable fluorescent source reconstruction, but also demonstrates enhanced robustness to noise. PMID:27375949

  18. The influence of hamstring autograft size on patient reported outcomes and risk of revision following anterior cruciate ligament reconstruction: A MOON cohort study

    PubMed Central

    Mariscalco, Michael W.; Flanigan, David C.; Mitchell, Joshua; Pedroza, Angela D.; Jones, Morgan H.; Andrish, Jack T.; Parker, Richard D.; Kaeding, Christopher C.; Magnussen, Robert A.

    2013-01-01

    Purpose The purpose of this study is to evaluate the effect of graft size on patient-reported outcomes and revision risk following ACL reconstruction. Methods A retrospective chart review of prospectively collected cohort data, 263 of 320 consecutive patients (82.2%) undergoing primary ACL reconstruction with hamstring autograft were evaluated. Graft size, femoral tunnel drilling technique, patient age, sex, and BMI at the time of ACL reconstruction, pre-operative and 2-year post-operative KOOS and IKDC scores, and whether each patient underwent revision ACL reconstruction during the 2 year follow-up period were recorded. Revision was used as a marker for graft failure. The relationship between graft size and patient-reported outcomes was determined by multiple linear regression. The relationship between graft size and risk of revision was determined by dichotomizing graft size at 8mm and stratifying by age. Results After controlling for age, sex, operative side, surgeon, BMI, graft choice, and femoral tunnel drilling technique, a 1 mm increased in graft size was noted to correlate with 3.3-point increase in the KOOS-pain subscale (p = 0.003), a 2.0-point increased in the KOOS activities of daily living subscale (p = 0.034), a 5.2-point increase in the KOOS-sport/recreation function subscale (p = 0.004), and a 3.4-point increase in the subjective IKDC score (p = 0.026). Revision was required in 0 of 64 patients (0.0%) with grafts greater than 8mm in diameter and 14 of 199 patients (7.0%) with 8 mm or smaller grafts (p = 0.037). Among patients age 18 and under, revision was required in 0 of 14 patients (0.0%) with grafts greater than 8mm in diameter and 13 of 71 patients (18.3 %) with 8 mm or smaller grafts. Conclusions Smaller hamstring autograft size is a predictor of poorer KOOS Sport and Recreation function 2 years following primary ACL reconstruction. Larger sample size is required to confirm the relationship between graft size and risk of revision ACL

  19. Reconstructed imaging of acoustic cloak using time-lapse reversal method

    NASA Astrophysics Data System (ADS)

    Zhou, Chen; Cheng, Ying; Xu, Jian-yi; Li, Bo; Liu, Xiao-jun

    2014-08-01

    We proposed and investigated a solution to the inverse acoustic cloak problem, an anti-stealth technology to make cloaks visible, using the time-lapse reversal (TLR) method. The TLR method reconstructs the image of an unknown acoustic cloak by utilizing scattered acoustic waves. Compared to previous anti-stealth methods, the TLR method can determine not only the existence of a cloak but also its exact geometric information like definite shape, size, and position. Here, we present the process for TLR reconstruction based on time reversal invariance. This technology may have potential applications in detecting various types of cloaks with different geometric parameters.

  20. Reconstruction of the anterior cruciate ligament: a comparison between bone-patellar tendon-bone grafts and fourstrand hamstring grafts

    PubMed Central

    Razi, Mohammad; Sarzaeem, Mohammad Mahdi; Kazemian, Gholam Hossein; Najafi, Farideh; Najafi, Mohammad Amin

    2014-01-01

    Background: Disruption of anterior cruciate ligament (ACL) is a common ligamentous injury of the knee. The choice of graft for (ACL) reconstruction remains controversial. This prospective, randomized clinical trial aimed to compare clinical results of bone-patellar tendon-bone (BPTB) grafts and four-strand semitendinosus-gracilis (ST) grafts for ACL reconstruction over a 3-year follow-up interval. Methods: Seventy-one patients with an average age of 29± 4.5yearswere treated for torn ACL between 2008 and 2009. Forty-sixpatients underwent reconstruction with BPTB autograft, and 41 were treated with ST autograft. At the time of final follow-up, 37 patients in patella group and 34 patients in hamstring group were evaluated in terms of return to pre-injury activity level, pain, knee stability, range of motion, IKDC (International Knee Documentation Committee) score and complications. Results: At 36thmonth of follow-up, 34 (92%) and 28 (82%) patients in BPTB and ST group, respectively had good-to-excellent IKDC score (p > 0.05). The activity levels were higher in BPTB group (p> 0.05). At 3rd yearof follow up, the Lachman test was graded normal, for 23 (62%) and 11 (32%) patients in BPTB and ST group, respectively (p=0.019). Regarding the pivot-shift test, 29 (79%) and 15 (44%) patients in patella and hamstring group, respectively had normal test at the latest follow-up (p=0.021).There were no significant differences in terms of thigh circumference difference, effusion, knee range of motion, pain and complications. Conclusion: The results indicate a trend toward increased graft laxity and pivot-shift grades in patients undergoing reconstruction with hamstring autograft compared with patella tendon. However, the two groups had comparable results in terms of activity level and knee function. PMID:25694992

  1. A Reconstructed Discontinuous Galerkin Method for the Compressible Euler Equations on Arbitrary Grids

    SciTech Connect

    Hong Luo; Luquing Luo; Robert Nourgaliev; Vincent Mousseau

    2009-06-01

    A reconstruction-based discontinuous Galerkin (DG) method is presented for the solution of the compressible Euler equations on arbitrary grids. By taking advantage of handily available and yet invaluable information, namely the derivatives, in the context of the discontinuous Galerkin methods, a solution polynomial of one degree higher is reconstructed using a least-squares method. The stencils used in the reconstruction involve only the van Neumann neighborhood (face-neighboring cells) and are compact and consistent with the underlying DG method. The resulting DG method can be regarded as an improvement of a recovery-based DG method in the sense that it shares the same nice features as the recovery-based DG method, such as high accuracy and efficiency, and yet overcomes some of its shortcomings such as a lack of flexibility, compactness, and robustness. The developed DG method is used to compute a variety of flow problems on arbitrary meshes to demonstrate the accuracy and efficiency of the method. The numerical results indicate that this reconstructed DG method is able to obtain a third-order accurate solution at a slightly higher cost than its second-order DG method and provide an increase in performance over the third order DG method in terms of computing time and storage requirement.

  2. Reducing the effects of acoustic heterogeneity with an iterative reconstruction method from experimental data in microwave induced thermoacoustic tomography

    SciTech Connect

    Wang, Jinguo; Zhao, Zhiqin Song, Jian; Chen, Guoping; Nie, Zaiping; Liu, Qing-Huo

    2015-05-15

    Purpose: An iterative reconstruction method has been previously reported by the authors of this paper. However, the iterative reconstruction method was demonstrated by solely using the numerical simulations. It is essential to apply the iterative reconstruction method to practice conditions. The objective of this work is to validate the capability of the iterative reconstruction method for reducing the effects of acoustic heterogeneity with the experimental data in microwave induced thermoacoustic tomography. Methods: Most existing reconstruction methods need to combine the ultrasonic measurement technology to quantitatively measure the velocity distribution of heterogeneity, which increases the system complexity. Different to existing reconstruction methods, the iterative reconstruction method combines time reversal mirror technique, fast marching method, and simultaneous algebraic reconstruction technique to iteratively estimate the velocity distribution of heterogeneous tissue by solely using the measured data. Then, the estimated velocity distribution is used subsequently to reconstruct the highly accurate image of microwave absorption distribution. Experiments that a target placed in an acoustic heterogeneous environment are performed to validate the iterative reconstruction method. Results: By using the estimated velocity distribution, the target in an acoustic heterogeneous environment can be reconstructed with better shape and higher image contrast than targets that are reconstructed with a homogeneous velocity distribution. Conclusions: The distortions caused by the acoustic heterogeneity can be efficiently corrected by utilizing the velocity distribution estimated by the iterative reconstruction method. The advantage of the iterative reconstruction method over the existing correction methods is that it is successful in improving the quality of the image of microwave absorption distribution without increasing the system complexity.

  3. A modified arthroscopic anterior cruciate ligament double-bundle reconstruction technique with autogenous quadriceps tendon graft: remnant-preserving technique.

    PubMed

    Kim, Sung-Jae; Jo, Seung-Bae; Kim, Tai-Won; Chang, Ji-Hoon; Choi, Heon-Sik; Oh, Kyung-Soo

    2009-03-01

    Several techniques of anterior cruciate ligament (ACL) double-bundle reconstruction have been introduced to improve the functional outcome and restore normal kinematics of the knee. Meanwhile, a remnant-preserving technique was developed to preserve the proprioception and to enhance the revascularization of the reconstructed ACL. We developed double-bundle ACL reconstruction technique using autogenous quadriceps tendon graft while preserving the remnant. With this technique, two femoral sockets and one tibial tunnel are made. To preserve the remnant of the ACL, the rotational direction of the reamer was set to counterclockwise just before perforation of the tibial tunnel. To pass the graft more easily without disturbance of the remnant, the graft passage was achieved through the tibial tunnel. We suggest that the remnant-preserving technique could be an effective alternative considering its mechanical stability as well as the proprioception and vascularization recovery in arthroscopic double-bundle ACL reconstruction.

  4. An efficient MR image reconstruction method for arbitrary K-space trajectories without density compensation.

    PubMed

    Song, Jiayu; Liu, Q H

    2006-01-01

    Non-Cartesian sampling is widely used for fast magnetic resonance imaging (MRI). The well known gridding method usually requires density compensation to adjust the non-uniform sampling density, which is a major source of reconstruction error. Minimum-norm least square (MNLS) reconstruction, on the other hand, does not need density compensation, but requires intensive computations. In this paper, a new version of MNLS reconstruction method is developed using maximum likelihood and is speeded up by incorporating novel non-uniform fast Fourier transform (NUFFT) and bi-conjugate gradient fast Fourier transform (BCG-FFT) techniques. Studies on computer-simulated phantoms and a physically scanned phantom show improved reconstruction accuracy and signal-to-noise ratio compared to gridding method. The method is shown applicable to arbitrary k-space trajectory. Furthermore, we find that the method in fact performs un-blurring in the image space as an equivalent of density compensation in the k-space. Equalizing MNLS solution with gridding algorithm leads to new approaches of finding optimal density compensation functions (DCF). The method has been applied to radially encoded cardiac imaging on small animals. Reconstructed dynamic images of an in vivo mouse heart are shown. PMID:17946203

  5. Implementation of Open and Closed Kinetic Chain Quadriceps Strengthening Exercises after Anterior Cruciate Ligament Reconstruction.

    ERIC Educational Resources Information Center

    Ross, Michael D.; Denegar, Craig R.; Winzenried, Jay A.

    2001-01-01

    Reviews the effects of open kinetic chain (OKC) and closed kinetic chain (CKC) exercise on anterior cruciate ligament (ACL) strain and patellofemoral joint stress, suggesting a combination of the two for quadriceps strengthening after ACL reconstruction. Both OKC and CKC exercises may be modified and implemented for quadriceps strengthening after…

  6. An inversion identified in acl1-1 mutant functions as an enhancer of the acl1-1 phenotype.

    PubMed

    Kamata, Naoko; Komeda, Yoshibumi

    2008-08-01

    The Arabidopsis acaulis1-1 (acl1-1) mutant exhibits severe growth defects when grown at 22 degrees C. The leaves are tiny and curled and the inflorescence stems are short. We identified an inversion mutation in the original acl1-1 plants. The acl1-1 plants were crossed with Columbia wild-type, and the acl1-1 phenotype and the inversion were segregated in the F2 generation. Compared to the original acl1-1 plants with the inversion, the genuine acl1-1 plants without the inversion grew larger and their inflorescence stems grew longer at 22 degrees C. When the plants were grown at 24 degrees C, the differences in growth became more apparent. We investigated the expression of genes located in the inversion. Two genes that were located at each end of the inversion were disrupted, and full-length transcripts were not expressed. Expressions of some genes within and adjacent to the inversion were also altered. Our results indicate that the expression of multiple genes may be involved in the enhancement of the acl1-1 phenotype.

  7. A Reconstructed Discontinuous Galerkin Method for the Compressible Navier-Stokes Equations on Arbitrary Grids

    SciTech Connect

    Hong Luo; Luqing Luo; Robert Nourgaliev; Vincent A. Mousseau

    2010-01-01

    A reconstruction-based discontinuous Galerkin (RDG) method is presented for the solution of the compressible Navier-Stokes equations on arbitrary grids. The RDG method, originally developed for the compressible Euler equations, is extended to discretize viscous and heat fluxes in the Navier-Stokes equations using a so-called inter-cell reconstruction, where a smooth solution is locally reconstructed using a least-squares method from the underlying discontinuous DG solution. Similar to the recovery-based DG (rDG) methods, this reconstructed DG method eliminates the introduction of ad hoc penalty or coupling terms commonly found in traditional DG methods. Unlike rDG methods, this RDG method does not need to judiciously choose a proper form of a recovered polynomial, thus is simple, flexible, and robust, and can be used on arbitrary grids. The developed RDG method is used to compute a variety of flow problems on arbitrary meshes to demonstrate its accuracy, efficiency, robustness, and versatility. The numerical results indicate that this RDG method is able to deliver the same accuracy as the well-known Bassi-Rebay II scheme, at a half of its computing costs for the discretization of the viscous fluxes in the Navier-Stokes equations, clearly demonstrating its superior performance over the existing DG methods for solving the compressible Navier-Stokes equations.

  8. FUNCTIONAL PERFORMANCE AND KNEE LAXITY IN NORMAL INDIVIDUALS AND IN INDIVIDUALS SUBMITTED TO ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

    PubMed Central

    de Vasconcelos, Rodrigo Antunes; Bevilaqua-Grossi, Débora; Shimano, Antonio Carlos; Jansen Paccola, Cleber Antonio; Salvini, Tânia Fátima; Prado, Christiane Lanatovits; Mello Junior, Wilson A.

    2015-01-01

    The aim of this study was to analyze the correlation between deficits in the isokinetic peak torque of the knee extensors and flexors with hop tests, postoperative knee laxity and functional scores in normal and ACL- reconstructed subjects with patellar tendon and hamstring tendon autografts. Methods: Sixty male subjects were enrolled and subdivided into three groups: Twenty subjects without knee injuries (GC group) and two groups of 20 subjects submitted to ACL reconstruction with patellar tendon (GTP group) and hamstrings autograft (GTF group). Results: The results showed significant correlation between knee extensors peak torque and performance in the hop tests for GTF and GC groups. There are no significantly correlations between post op knee laxity and Lysholm score compared with the hop tests and peak torque deficits. Concerning the differences between groups, the GTP group showed greater peak torque deficits in knee extensors, worst Lysholm scores and higher percentage of individuals with lower limb symmetry index (ISM) < 90% in both hop tests when compared to the other two groups. Conclusion: It is not recommendable to use only one measurement instrument for the functional evaluation of ACL-reconstructed patients, because significant correlation between peak torque, subject's functional score, knee laxity and hop tests were not observed in all groups. PMID:26998464

  9. Evidence-based rehabilitation following anterior cruciate ligament reconstruction.

    PubMed

    van Grinsven, S; van Cingel, R E H; Holla, C J M; van Loon, C J M

    2010-08-01

    Following a bone-patellar tendon-bone autograft (BPTB) or four-stranded semitendinosus/gracilis tendons autograft (ST/G) anterior cruciate ligament (ACL) reconstruction, the speed and safety with which an athlete returns to sports (or regains the pre-injury level of function) depends on the rehabilitation protocol. Considering the large differences in clinical and outpatient protocols, there is no consensus regarding the content of such a rehabilitation program. Therefore, we conducted a systematic review to develop an optimal evidence-based rehabilitation protocol to enable unambiguous, practical and useful treatment after ACL reconstruction. The systematic literature search identified 1,096 citations published between January 1995 and December 2006. Thirty-two soundly based rehabilitation programs, randomized clinical trials (RCT's) and reviews were included in which common physical therapy modalities (instruction, bracing, cryotherapy, joint mobility training, muscle-strength training, gait re-education, training of neuromuscular function/balance and proprioception) or rehabilitation programs were evaluated following ACL reconstruction with a BPTB or ST/G graft. Two reviews were excluded because of poor quality. Finally, the extracted data were combined with information from background literature to develop an optimal evidence-based rehabilitation protocol. The results clearly indicated that an accelerated protocol without postoperative bracing, in which reduction of pain, swelling and inflammation, regaining range of motion, strength and neuromuscular control are the most important aims, has important advantages and does not lead to stability problems. Preclinical sessions, clear starting times and control of the rehabilitation aims with objective and subjective tests facilitate an uncomplicated rehabilitation course. Consensus about this evidence-based accelerated protocol will not only enhance the speed and safety with which an athlete returns to sports, but

  10. Review of evolution of tunnel position in anterior cruciate ligament reconstruction

    PubMed Central

    Rayan, Faizal; Nanjayan, Shashi Kumar; Quah, Conal; Ramoutar, Darryl; Konan, Sujith; Haddad, Fares S

    2015-01-01

    Anterior cruciate ligament (ACL) rupture is one of the commonest knee sport injuries. The annual incidence of the ACL injury is between 100000-200000 in the United States. Worldwide around 400000 ACL reconstructions are performed in a year. The goal of ACL reconstruction is to restore the normal knee anatomy and kinesiology. The tibial and femoral tunnel placements are of primordial importance in achieving this outcome. Other factors that influence successful reconstruction are types of grafts, surgical techniques and rehabilitation programmes. A comprehensive understanding of ACL anatomy has led to the development of newer techniques supplemented by more robust biological and mechanical concepts. In this review we are mainly focussing on the evolution of tunnel placement in ACL reconstruction, focusing on three main categories, i.e., anatomical, biological and clinical outcomes. The importance of tunnel placement in the success of ACL reconstruction is well researched. Definite clinical and functional data is lacking to establish the superiority of the single or double bundle reconstruction technique. While there is a trend towards the use of anteromedial portals for femoral tunnel placement, their clinical superiority over trans-tibial tunnels is yet to be established. PMID:25793165

  11. Bone-patellar tendon-bone autograft versus LARS artificial ligament for anterior cruciate ligament reconstruction.

    PubMed

    Pan, Xiaoyun; Wen, Hong; Wang, Lide; Ge, Tichi

    2013-10-01

    The optimized graft for use in anterior cruciate ligament (ACL) reconstruction is still in controversy. The bone-patellar tendon-bone (BPTB) autograft has been accepted as the gold standard for ACL reconstruction. However, donor site morbidities cannot be avoided after this treatment. The artificial ligament of ligament advanced reinforcement system (LARS) has been recommended for ACL reconstruction. The purpose of this study is to compare the midterm outcome of ACL reconstruction using BPTB autografts or LARS ligaments. Between July 2004 and March 2006, the ACL reconstruction using BPTB autografts in 30 patients and LARS ligaments in 32 patients was performed. All patients were followed up for at least 4 years and evaluated using the Lysholm knee score, Tegner score, International Knee Documentation Committee (IKDC) score, and KT-1000 arthrometer test. There were no significant differences between the two groups with respect to the data of Lysholm scores, Tegner scores, IKDC scores, and KT-1000 arthrometer test at the latest follow-up. Our study demonstrates that the similarly good clinical results are obtained after ACL reconstruction using BPTB autografts or LARS ligaments at midterm follow-up. In addition to BPTB autografts, the LARS ligament may be a satisfactory treatment option for ACL rupture.

  12. Noninvasive reconstruction of cardiac transmembrane potentials using a kernelized extreme learning method

    NASA Astrophysics Data System (ADS)

    Jiang, Mingfeng; Zhang, Heng; Zhu, Lingyan; Cao, Li; Wang, Yaming; Xia, Ling; Gong, Yinglan

    2015-04-01

    Non-invasively reconstructing the cardiac transmembrane potentials (TMPs) from body surface potentials can act as a regression problem. The support vector regression (SVR) method is often used to solve the regression problem, however the computational complexity of the SVR training algorithm is usually intensive. In this paper, another learning algorithm, termed as extreme learning machine (ELM), is proposed to reconstruct the cardiac transmembrane potentials. Moreover, ELM can be extended to single-hidden layer feed forward neural networks with kernel matrix (kernelized ELM), which can achieve a good generalization performance at a fast learning speed. Based on the realistic heart-torso models, a normal and two abnormal ventricular activation cases are applied for training and testing the regression model. The experimental results show that the ELM method can perform a better regression ability than the single SVR method in terms of the TMPs reconstruction accuracy and reconstruction speed. Moreover, compared with the ELM method, the kernelized ELM method features a good approximation and generalization ability when reconstructing the TMPs.

  13. Rates and Determinants of Return to Play After Anterior Cruciate Ligament Reconstruction in NCAA Division 1 College Football Athletes

    PubMed Central

    Daruwalla, Jimmy H.; Greis, Patrick E.; Hancock, Robert; Xerogeanes, John W.

    2014-01-01

    Background: For competitive athletes, return to play (RTP) and return to preinjury levels of performance after anterior cruciate ligament (ACL) reconstruction are the main goals of surgery. Although outcomes of ACL surgery are well studied, details on factors influencing RTP in elite college football players have not been evaluated thoroughly. Purpose: To determine the rate of RTP following ACL surgery among National Collegiate Athletic Association (NCAA) Division 1 collegiate football athletes and to examine variables that may affect these rates. The hypothesis was that the RTP rate in this cohort will be influenced by factors reflecting skill and accomplishment; that is, athletes higher on the depth chart, those on scholarship, and those later in their careers will have higher RTP rates. It was also predicted that graft type and concomitant procedures may have an effect on RTP rates. Study Design: Case series; Level of evidence, 4. Methods: Using athlete- and surgery-specific data from participating institutions in 3 major Division 1 college football conferences, information on athletes who had ACL reconstruction from 2004 through 2010 was collected. Statistical analyses were performed to determine the RTP rate as a function of the variables, such as depth chart position, in the data collected. Results: Of the 184-player cohort, 82% of the athletes, including 94% of starters, were able to RTP. Rates were greater among athletes higher on the depth chart (P = .004) and on scholarship (P = .008). Year of eligibility also affected RTP rates (P = .047), which increased from the redshirt and freshman year to the sophomore and junior years, but then decreased slightly into the senior and fifth-year senior seasons. The use of an autograft versus allograft was associated with increased RTP (P = .045). There was no significant difference (P = .18) between players who underwent an isolated ACL reconstruction versus those who underwent additional procedures. Conclusion: More

  14. Tibial Tunnel Cyst Formation after Anterior Cruciate Ligament Reconstruction Using a Non-Bioabsorbable Interference Screw.

    PubMed

    Joshi, Yogesh V; Bhaskar, Deepu; Phaltankar, Padmanabh M; Charalambous, Charalambos P

    2015-12-01

    Tibial cyst formation following the use of bioabsorbable interference screws in anterior cruciate ligament (ACL) reconstruction is well-described; however, cyst formation after the use of metallic interference screws is not well-documented. We describe a case of osteolytic lesion of the proximal tibia presenting to us 20 years after ACL reconstruction using an autologous bone-tendon-bone graft. The original graft fixation technique was interference fixation with a metal screw in the tibial and femoral tunnels. A two-stage revision reconstruction of the ACL was undertaken with curettage and bone grafting of the tibial lesion in the first stage and reconstruction using a four-strand hamstring tendon in the second stage. The patient recovered satisfactorily with complete healing of the cyst and returned to pre-injury level of activities. We have reviewed case reports and case series that describe the aetiology of intra-osseous cyst formation following ACL reconstruction. PMID:26673117

  15. Runout error correction in tomographic reconstruction by intensity summation method.

    PubMed

    Kwon, Ik Hwan; Lim, Jun; Hong, Chung Ki

    2016-09-01

    An alignment method for correction of the axial and radial runout errors of the rotation stage in X-ray phase-contrast computed tomography has been developed. Only intensity information was used, without extra hardware or complicated calculation. Notably, the method, as demonstrated herein, can utilize the halo artifact to determine displacement. PMID:27577781

  16. DETECTORS AND EXPERIMENTAL METHODS Study of low momentum track reconstruction for the BESIII main drift chamber

    NASA Astrophysics Data System (ADS)

    Jia, Lu-Kui; Mao, Ze-Pu; Li, Wei-Dong; Cao, Guo-Fu; Cao, Xue-Xiang; Deng, Zi-Yan; He, Kang-Lin; Liu, Chun-Yan; Liu, Huai-Min; Liu, Qiu-Guang; Ma, Qiu-Mei; Ma, Xiang; Qiu, Jin-Fa; Tian, Hao-Lai; Wang, Ji-Ke; Wu, Ling-Hui; Yuan, Ye; Zang, Shi-Lei; Zhang, Chang-Chun; Zhang, Lei; Zhang, Yao; Zhu, Kai; Zou, Jia-Heng

    2010-12-01

    In order to overcome the difficulty brought by the circling charged tracks with transverse momentum less than 120 MeV in the BESIII Main Drift Chamber (MDC), a specialized method called TCurlFinder was developed. This tracking method focuses on the charged track reconstruction under 120 MeV and possesses a special mechanism to reject background noise hits. The performance of the package has been carefully checked and tuned by both Monte Carlo data and real data. The study shows that this tracking method could obviously enhance the reconstruction efficiency in the low transverse momentum region, providing physics analysis with more and reliable data.

  17. Noise reduction in computed tomography using a multiplicative continuous-time image reconstruction method

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Yusaku; Kojima, Takeshi; Yoshinaga, Tetsuya

    2016-03-01

    In clinical X-ray computed tomography (CT), filtered back-projection as a transform method and iterative reconstruction such as the maximum-likelihood expectation-maximization (ML-EM) method are known methods to reconstruct tomographic images. As the other reconstruction method, we have presented a continuous-time image reconstruction (CIR) system described by a nonlinear dynamical system, based on the idea of continuous methods for solving tomographic inverse problems. Recently, we have also proposed a multiplicative CIR system described by differential equations based on the minimization of a weighted Kullback-Leibler divergence. We prove theoretically that the divergence measure decreases along the solution to the CIR system, for consistent inverse problems. In consideration of the noisy nature of projections in clinical CT, the inverse problem belongs to the category of ill-posed problems. The performance of a noise-reduction scheme for a new (previously developed) CIR system was investigated by means of numerical experiments using a circular phantom image. Compared to the conventional CIR and the ML-EM methods, the proposed CIR method has an advantage on noisy projection with lower signal-to-noise ratios in terms of the divergence measure on the actual image under the same common measure observed via the projection data. The results lead to the conclusion that the multiplicative CIR method is more effective and robust for noise reduction in CT compared to the ML-EM as well as conventional CIR methods.

  18. A Reconstructed Discontinuous Galerkin Method for the Compressible Flows on Unstructured Tetrahedral Grids

    SciTech Connect

    Hong Luo; Yidong Xia; Robert Nourgaliev; Chunpei Cai

    2011-06-01

    A reconstruction-based discontinuous Galerkin (RDG) method is presented for the solution of the compressible Navier-Stokes equations on unstructured tetrahedral grids. The RDG method, originally developed for the compressible Euler equations, is extended to discretize viscous and heat fluxes in the Navier-Stokes equations using a so-called inter-cell reconstruction, where a smooth solution is locally reconstructed using a least-squares method from the underlying discontinuous DG solution. Similar to the recovery-based DG (rDG) methods, this reconstructed DG method eliminates the introduction of ad hoc penalty or coupling terms commonly found in traditional DG methods. Unlike rDG methods, this RDG method does not need to judiciously choose a proper form of a recovered polynomial, thus is simple, flexible, and robust, and can be used on unstructured grids. The preliminary results indicate that this RDG method is stable on unstructured tetrahedral grids, and provides a viable and attractive alternative for the discretization of the viscous and heat fluxes in the Navier-Stokes equations.

  19. Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Arcuri, Francisco; Barclay, Fernando; Nacul, Ivan

    2015-01-01

    Introduction: The most recent advances in ACL reconstruction try to reproduce the anatomic femoral and tibial footprints as close as possible. Creating independent tunnels would allow an optimal of the entry point and the femoral tunnel obliquity, and together with an adequate reamer diameter they wouldreproduce with greater certainty the anatomy. Objective: To compare the radiographic parameters of the femoral and tibial tunnel positions in two groups of patients, one operated with a transtibial and other with transportal anatomic techniques. Materials and Methods: From December 2012 to December 2013, 59 patients with a primary ACL reconstruction divided in two groups, a trans tibial technique (TT), 19 patients, and an transportal one (TP) with 40 patients were prospectively evaluated with AP and lateral X-rays. The femoral tunnel angle, the insertion site with respect of the Blumensaat line, the trans osseous distance, the tibial tunnel position as a percentage of the tibial plateau in the AP and lateral views. And finally the tibial tunnel angle in the AP and Lateral views. Results: The femoral tunnel angle was in the TP group of 45,92º and in the TT one 24,53º, p 0,002. The insertion site percentage of the Blumensaat line was of 20,96 in TP and 20,74 in the TT, p 0,681.Trans osseous distance was in the TP of 3,43 cm and in the TT of 4,79 cm, p <0,000. The tibial tunnel position as a percentage in the AP tibial plateau was of 44,35 in TP and of 40,80 TT with a p of 0,076. The tibial tunnel position as a percentage of the lateral tibial plateau was of 28,70 in TP and 34,53 in TT with a p 0,367. Tibial tunnel angle in the AP was of 73,48º in TP and 62,81 in TT with a p of 0,002, and in the lateral plateau of 114,69º in TP and 112,79º in TT with a p of 0,427. Conclusion: It is possible to create tibial and femoral tunnel in optimal positions but not equal between both groups. Creating independent tunnels allow a more anterior and vertical tibial tunnel

  20. The Extratropical Northern Hemisphere Temperature Reconstruction during the Last Millennium Based on a Novel Method.

    PubMed

    Xing, Pei; Chen, Xin; Luo, Yong; Nie, Suping; Zhao, Zongci; Huang, Jianbin; Wang, Shaowu

    2016-01-01

    Large-scale climate history of the past millennium reconstructed solely from tree-ring data is prone to underestimate the amplitude of low-frequency variability. In this paper, we aimed at solving this problem by utilizing a novel method termed "MDVM", which was a combination of the ensemble empirical mode decomposition (EEMD) and variance matching techniques. We compiled a set of 211 tree-ring records from the extratropical Northern Hemisphere (30-90°N) in an effort to develop a new reconstruction of the annual mean temperature by the MDVM method. Among these dataset, a number of 126 records were screened out to reconstruct temperature variability longer than decadal scale for the period 850-2000 AD. The MDVM reconstruction depicted significant low-frequency variability in the past millennium with evident Medieval Warm Period (MWP) over the interval 950-1150 AD and pronounced Little Ice Age (LIA) cumulating in 1450-1850 AD. In the context of 1150-year reconstruction, the accelerating warming in 20th century was likely unprecedented, and the coldest decades appeared in the 1640s, 1600s and 1580s, whereas the warmest decades occurred in the 1990s, 1940s and 1930s. Additionally, the MDVM reconstruction covaried broadly with changes in natural radiative forcing, and especially showed distinct footprints of multiple volcanic eruptions in the last millennium. Comparisons of our results with previous reconstructions and model simulations showed the efficiency of the MDVM method on capturing low-frequency variability, particularly much colder signals of the LIA relative to the reference period. Our results demonstrated that the MDVM method has advantages in studying large-scale and low-frequency climate signals using pure tree-ring data.

  1. The Extratropical Northern Hemisphere Temperature Reconstruction during the Last Millennium Based on a Novel Method

    PubMed Central

    Xing, Pei; Chen, Xin; Luo, Yong; Nie, Suping; Zhao, Zongci; Huang, Jianbin; Wang, Shaowu

    2016-01-01

    Large-scale climate history of the past millennium reconstructed solely from tree-ring data is prone to underestimate the amplitude of low-frequency variability. In this paper, we aimed at solving this problem by utilizing a novel method termed “MDVM”, which was a combination of the ensemble empirical mode decomposition (EEMD) and variance matching techniques. We compiled a set of 211 tree-ring records from the extratropical Northern Hemisphere (30–90°N) in an effort to develop a new reconstruction of the annual mean temperature by the MDVM method. Among these dataset, a number of 126 records were screened out to reconstruct temperature variability longer than decadal scale for the period 850–2000 AD. The MDVM reconstruction depicted significant low-frequency variability in the past millennium with evident Medieval Warm Period (MWP) over the interval 950–1150 AD and pronounced Little Ice Age (LIA) cumulating in 1450–1850 AD. In the context of 1150-year reconstruction, the accelerating warming in 20th century was likely unprecedented, and the coldest decades appeared in the 1640s, 1600s and 1580s, whereas the warmest decades occurred in the 1990s, 1940s and 1930s. Additionally, the MDVM reconstruction covaried broadly with changes in natural radiative forcing, and especially showed distinct footprints of multiple volcanic eruptions in the last millennium. Comparisons of our results with previous reconstructions and model simulations showed the efficiency of the MDVM method on capturing low-frequency variability, particularly much colder signals of the LIA relative to the reference period. Our results demonstrated that the MDVM method has advantages in studying large-scale and low-frequency climate signals using pure tree-ring data. PMID:26751947

  2. Addition of Autologous Mesenchymal Stem Cells to Whole Blood for Bio-Enhanced ACL Repair has No Benefit in the Porcine Model

    PubMed Central

    Proffen, Benedikt L.; Vavken, Patrick; Haslauer, Carla M.; Fleming, Braden C.; Harris, Chad E.; Machan, Jason T.; Murray, Martha M.

    2015-01-01

    Background Co-culture of mesenchymal stem cells (MSCs) from the retropatellar fat pad and peripheral blood has been shown to stimulate anterior cruciate ligament (ACL) fibroblast proliferation and collagen production in vitro. Current techniques of bio-enhanced ACL repair in animal studies involve adding a biologic scaffold, in this case an extracellular matrix based scaffold saturated with autologous whole blood, to a simple suture repair of the ligament. Whether the enrichment of whole blood with MSCs would further improve the in vivo results of bio-enhanced ACL repair was investigated. Hypothesis/Purpose The hypothesis was that the addition of MSCs derived from adipose tissue or peripheral blood to the blood-extracellular matrix composite, which is used in bio-enhanced ACL repair to stimulate healing, would improve the biomechanical properties of a bio-enhanced ACL repair after 15 weeks of healing. Study Design Controlled laboratory study. Methods Twenty-four adolescent Yucatan mini-pigs underwent ACL transection followed by: 1) bio-enhanced ACL repair, 2) bio-enhanced ACL repair with the addition of autologous adipose-derived MSCs and 3) bio-enhanced ACL repair with the addition of autologous peripheral blood derived MSCs. After fifteen weeks of healing, structural properties of the ACL (yield & failure load, linear stiffness) were measured. Cell and vascular density were measured in the repaired ACL via histology, and its tissue structure was qualitatively evaluated using the Advanced Ligament Maturity Index. Results After fifteen weeks of healing, there were no significant improvements in the biomechanical or histological properties with the addition of adipose-derived MSCs. The only significant change with the addition of peripheral blood MSCs was an increase in knee anteroposterior (AP) laxity when measured at 30 degrees of flexion. Conclusions These findings suggest that the addition of adipose or peripheral blood MSCs to whole blood prior to saturation of

  3. Local and Non-local Regularization Techniques in Emission (PET/SPECT) Tomographic Image Reconstruction Methods.

    PubMed

    Ahmad, Munir; Shahzad, Tasawar; Masood, Khalid; Rashid, Khalid; Tanveer, Muhammad; Iqbal, Rabail; Hussain, Nasir; Shahid, Abubakar; Fazal-E-Aleem

    2016-06-01

    Emission tomographic image reconstruction is an ill-posed problem due to limited and noisy data and various image-degrading effects affecting the data and leads to noisy reconstructions. Explicit regularization, through iterative reconstruction methods, is considered better to compensate for reconstruction-based noise. Local smoothing and edge-preserving regularization methods can reduce reconstruction-based noise. However, these methods produce overly smoothed images or blocky artefacts in the final image because they can only exploit local image properties. Recently, non-local regularization techniques have been introduced, to overcome these problems, by incorporating geometrical global continuity and connectivity present in the objective image. These techniques can overcome drawbacks of local regularization methods; however, they also have certain limitations, such as choice of the regularization function, neighbourhood size or calibration of several empirical parameters involved. This work compares different local and non-local regularization techniques used in emission tomographic imaging in general and emission computed tomography in specific for improved quality of the resultant images.

  4. L{sub 1/2} regularization based numerical method for effective reconstruction of bioluminescence tomography

    SciTech Connect

    Chen, Xueli E-mail: jimleung@mail.xidian.edu.cn; Yang, Defu; Zhang, Qitan; Liang, Jimin E-mail: jimleung@mail.xidian.edu.cn

    2014-05-14

    Even though bioluminescence tomography (BLT) exhibits significant potential and wide applications in macroscopic imaging of small animals in vivo, the inverse reconstruction is still a tough problem that has plagued researchers in a related area. The ill-posedness of inverse reconstruction arises from insufficient measurements and modeling errors, so that the inverse reconstruction cannot be solved directly. In this study, an l{sub 1/2} regularization based numerical method was developed for effective reconstruction of BLT. In the method, the inverse reconstruction of BLT was constrained into an l{sub 1/2} regularization problem, and then the weighted interior-point algorithm (WIPA) was applied to solve the problem through transforming it into obtaining the solution of a series of l{sub 1} regularizers. The feasibility and effectiveness of the proposed method were demonstrated with numerical simulations on a digital mouse. Stability verification experiments further illustrated the robustness of the proposed method for different levels of Gaussian noise.

  5. A physics-based intravascular ultrasound image reconstruction method for lumen segmentation.

    PubMed

    Mendizabal-Ruiz, Gerardo; Kakadiaris, Ioannis A

    2016-08-01

    Intravascular ultrasound (IVUS) refers to the medical imaging technique consisting of a miniaturized ultrasound transducer located at the tip of a catheter that can be introduced in the blood vessels providing high-resolution, cross-sectional images of their interior. Current methods for the generation of an IVUS image reconstruction from radio frequency (RF) data do not account for the physics involved in the interaction between the IVUS ultrasound signal and the tissues of the vessel. In this paper, we present a novel method to generate an IVUS image reconstruction based on the use of a scattering model that considers the tissues of the vessel as a distribution of three-dimensional point scatterers. We evaluated the impact of employing the proposed IVUS image reconstruction method in the segmentation of the lumen/wall interface on 40MHz IVUS data using an existing automatic lumen segmentation method. We compared the results with those obtained using the B-mode reconstruction on 600 randomly selected frames from twelve pullback sequences acquired from rabbit aortas and different arteries of swine. Our results indicate the feasibility of employing the proposed IVUS image reconstruction for the segmentation of the lumen.

  6. Meshless reconstruction method for fluorescence molecular tomography based on compactly supported radial basis function

    NASA Astrophysics Data System (ADS)

    An, Yu; Liu, Jie; Zhang, Guanglei; Ye, Jinzuo; Mao, Yamin; Jiang, Shixin; Shang, Wenting; Du, Yang; Chi, Chongwei; Tian, Jie

    2015-10-01

    Fluorescence molecular tomography (FMT) is a promising tool in the study of cancer, drug discovery, and disease diagnosis, enabling noninvasive and quantitative imaging of the biodistribution of fluorophores in deep tissues via image reconstruction techniques. Conventional reconstruction methods based on the finite-element method (FEM) have achieved acceptable stability and efficiency. However, some inherent shortcomings in FEM meshes, such as time consumption in mesh generation and a large discretization error, limit further biomedical application. In this paper, we propose a meshless method for reconstruction of FMT (MM-FMT) using compactly supported radial basis functions (CSRBFs). With CSRBFs, the image domain can be accurately expressed by continuous CSRBFs, avoiding the discretization error to a certain degree. After direct collocation with CSRBFs, the conventional optimization techniques, including Tikhonov, L1-norm iteration shrinkage (L1-IS), and sparsity adaptive matching pursuit, were adopted to solve the meshless reconstruction. To evaluate the performance of the proposed MM-FMT, we performed numerical heterogeneous mouse experiments and in vivo bead-implanted mouse experiments. The results suggest that the proposed MM-FMT method can reduce the position error of the reconstruction result to smaller than 0.4 mm for the double-source case, which is a significant improvement for FMT.

  7. Meshless reconstruction method for fluorescence molecular tomography based on compactly supported radial basis function.

    PubMed

    An, Yu; Liu, Jie; Zhang, Guanglei; Ye, Jinzuo; Mao, Yamin; Jiang, Shixin; Shang, Wenting; Du, Yang; Chi, Chongwei; Tian, Jie

    2015-10-01

    Fluorescence molecular tomography (FMT) is a promising tool in the study of cancer, drug discovery, and disease diagnosis, enabling noninvasive and quantitative imaging of the biodistribution of fluorophores in deep tissues via image reconstruction techniques. Conventional reconstruction methods based on the finite-element method (FEM) have achieved acceptable stability and efficiency. However, some inherent shortcomings in FEM meshes, such as time consumption in mesh generation and a large discretization error, limit further biomedical application. In this paper, we propose a meshless method for reconstruction of FMT (MM-FMT) using compactly supported radial basis functions (CSRBFs). With CSRBFs, the image domain can be accurately expressed by continuous CSRBFs, avoiding the discretization error to a certain degree. After direct collocation with CSRBFs, the conventional optimization techniques, including Tikhonov, L1-norm iteration shrinkage (L1-IS), and sparsity adaptive matching pursuit, were adopted to solve the meshless reconstruction. To evaluate the performance of the proposed MM-FMT, we performed numerical heterogeneous mouse experiments and in vivo bead-implanted mouse experiments. The results suggest that the proposed MM-FMT method can reduce the position error of the reconstruction result to smaller than 0.4 mm for the double-source case, which is a significant improvement for FMT. PMID:26451513

  8. A physics-based intravascular ultrasound image reconstruction method for lumen segmentation.

    PubMed

    Mendizabal-Ruiz, Gerardo; Kakadiaris, Ioannis A

    2016-08-01

    Intravascular ultrasound (IVUS) refers to the medical imaging technique consisting of a miniaturized ultrasound transducer located at the tip of a catheter that can be introduced in the blood vessels providing high-resolution, cross-sectional images of their interior. Current methods for the generation of an IVUS image reconstruction from radio frequency (RF) data do not account for the physics involved in the interaction between the IVUS ultrasound signal and the tissues of the vessel. In this paper, we present a novel method to generate an IVUS image reconstruction based on the use of a scattering model that considers the tissues of the vessel as a distribution of three-dimensional point scatterers. We evaluated the impact of employing the proposed IVUS image reconstruction method in the segmentation of the lumen/wall interface on 40MHz IVUS data using an existing automatic lumen segmentation method. We compared the results with those obtained using the B-mode reconstruction on 600 randomly selected frames from twelve pullback sequences acquired from rabbit aortas and different arteries of swine. Our results indicate the feasibility of employing the proposed IVUS image reconstruction for the segmentation of the lumen. PMID:27235803

  9. A diffusion-based truncated projection artifact reduction method for iterative digital breast tomosynthesis reconstruction

    NASA Astrophysics Data System (ADS)

    Lu, Yao; Chan, Heang-Ping; Wei, Jun; Hadjiiski, Lubomir M.

    2013-02-01

    Digital breast tomosynthesis (DBT) has strong promise to improve sensitivity for detecting breast cancer. DBT reconstruction estimates the breast tissue attenuation using projection views (PVs) acquired in a limited angular range. Because of the limited field of view (FOV) of the detector, the PVs may not completely cover the breast in the x-ray source motion direction at large projection angles. The voxels in the imaged volume cannot be updated when they are outside the FOV, thus causing a discontinuity in intensity across the FOV boundaries in the reconstructed slices, which we refer to as the truncated projection artifact (TPA). Most existing TPA reduction methods were developed for the filtered backprojection method in the context of computed tomography. In this study, we developed a new diffusion-based method to reduce TPAs during DBT reconstruction using the simultaneous algebraic reconstruction technique (SART). Our TPA reduction method compensates for the discontinuity in background intensity outside the FOV of the current PV after each PV updating in SART. The difference in voxel values across the FOV boundary is smoothly diffused to the region beyond the FOV of the current PV. Diffusion-based background intensity estimation is performed iteratively to avoid structured artifacts. The method is applicable to TPA in both the forward and backward directions of the PVs and for any number of iterations during reconstruction. The effectiveness of the new method was evaluated by comparing the visual quality of the reconstructed slices and the measured discontinuities across the TPA with and without artifact correction at various iterations. The results demonstrated that the diffusion-based intensity compensation method reduced the TPA while preserving the detailed tissue structures. The visibility of breast lesions obscured by the TPA was improved after artifact reduction.

  10. A sampling method for the reconstruction of a periodic interface in a layered medium

    NASA Astrophysics Data System (ADS)

    Sun, Guanying; Zhang, Ruming

    2016-07-01

    In this paper, we consider the inverse problem of reconstructing periodic interfaces in a two-layered medium with TM-mode. We propose a sampling-type method to recover the top periodic interface from the near-field data measured on a straight line above the total structure. Finally, numerical experiments are illustrated to show the effectiveness of the method.

  11. A Comparison of Affect Ratings Obtained with Ecological Momentary Assessment and the Day Reconstruction Method

    ERIC Educational Resources Information Center

    Dockray, Samantha; Grant, Nina; Stone, Arthur A.; Kahneman, Daniel; Wardle, Jane; Steptoe, Andrew

    2010-01-01

    Measurement of affective states in everyday life is of fundamental importance in many types of quality of life, health, and psychological research. Ecological momentary assessment (EMA) is the recognized method of choice, but the respondent burden can be high. The day reconstruction method (DRM) was developed by Kahneman and colleagues ("Science,"…

  12. Fast and robust reconstruction for fluorescence molecular tomography via a sparsity adaptive subspace pursuit method.

    PubMed

    Ye, Jinzuo; Chi, Chongwei; Xue, Zhenwen; Wu, Ping; An, Yu; Xu, Han; Zhang, Shuang; Tian, Jie

    2014-02-01

    Fluorescence molecular tomography (FMT), as a promising imaging modality, can three-dimensionally locate the specific tumor position in small animals. However, it remains challenging for effective and robust reconstruction of fluorescent probe distribution in animals. In this paper, we present a novel method based on sparsity adaptive subspace pursuit (SASP) for FMT reconstruction. Some innovative strategies including subspace projection, the bottom-up sparsity adaptive approach, and backtracking technique are associated with the SASP method, which guarantees the accuracy, efficiency, and robustness for FMT reconstruction. Three numerical experiments based on a mouse-mimicking heterogeneous phantom have been performed to validate the feasibility of the SASP method. The results show that the proposed SASP method can achieve satisfactory source localization with a bias less than 1mm; the efficiency of the method is much faster than mainstream reconstruction methods; and this approach is robust even under quite ill-posed condition. Furthermore, we have applied this method to an in vivo mouse model, and the results demonstrate the feasibility of the practical FMT application with the SASP method.

  13. Method and apparatus for reconstructing in-cylinder pressure and correcting for signal decay

    DOEpatents

    Huang, Jian

    2013-03-12

    A method comprises steps for reconstructing in-cylinder pressure data from a vibration signal collected from a vibration sensor mounted on an engine component where it can generate a signal with a high signal-to-noise ratio, and correcting the vibration signal for errors introduced by vibration signal charge decay and sensor sensitivity. The correction factors are determined as a function of estimated motoring pressure and the measured vibration signal itself with each of these being associated with the same engine cycle. Accordingly, the method corrects for charge decay and changes in sensor sensitivity responsive to different engine conditions to allow greater accuracy in the reconstructed in-cylinder pressure data. An apparatus is also disclosed for practicing the disclosed method, comprising a vibration sensor, a data acquisition unit for receiving the vibration signal, a computer processing unit for processing the acquired signal and a controller for controlling the engine operation based on the reconstructed in-cylinder pressure.

  14. Anterior cruciate ligament reconstruction with BPTB autograft, irradiated versus non-irradiated allograft: a prospective randomized clinical study.

    PubMed

    Sun, Kang; Tian, Shaoqi; Zhang, Jihua; Xia, Changsuo; Zhang, Cailong; Yu, Tengbo

    2009-05-01

    activity level decreased and the patients felt uncomfortable more often in the irradiated allograft group. The statistical analysis showed no significant difference between the non-irradiated allograft group and the autograft group according to the aforementioned evaluations, except that patients in the allograft group had a shorter operation time and a longer duration of postoperative fever. When comparing the postoperative duration of fever of the two allograft groups, there was also a trend that the irradiated allograft group was longer than the non-irradiated allograft group, but no significant difference was found. When the patients had a fever, the laboratory examinations of all patients were almost normal (Blood routine was normal, the values of ESR were 5 - 16 mm/h, CRP were 3 - 10 mg/l). On the basis of our study, we concluded that patients undergoing ACL reconstruction with BPTB non-irradiated allograft or autograft had similar clinical outcomes. Non-irradiated BPTB allograft is a reasonable alternative to autograft for ACL reconstruction. While the short term clinical outcomes of the ACL reconstruction with irradiated BPTB allograft were adversely affected with an increased failure rate. The less than satisfactory results led the senior authors to discontinue the use of irradiated BPTB allograft in ACL surgery and not to advocate that gamma irradiation be used as a secondary sterilizing method. Further research into alternatives to gamma irradiation is needed.

  15. Psychological Factors Associated With Anterior Cruciate Ligament Reconstruction Recovery

    PubMed Central

    Christino, Melissa A.; Fleming, Braden C.; Machan, Jason T.; Shalvoy, Robert M.

    2016-01-01

    Background: Psychological factors may have underappreciated effects on surgical outcomes after anterior cruciate ligament (ACL) reconstruction; however, few studies have investigated the relationship between specific psychological factors, objective clinical data, and patient-oriented outcomes. Purpose: Psychological factors are significantly associated with patient perceptions and functional outcomes after ACL reconstruction. The purpose of this study was to demonstrate relationships between self-esteem, health locus of control, and psychological distress with objective clinical outcomes, patient-oriented outcomes, and return to sport. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Twenty-seven patients who were 6 to 24 months post–computer-assisted ACL reconstruction by a single surgeon consented to participate in the study (52% response rate). Participants had a 1-time visit with a physician consisting of: a physical examination, a single-leg hop test, KT-1000 arthrometer measurements, and survey completion. Psychological measures included the Multidimensional Health Locus of Control Scale, Rosenberg Self-Esteem Scale, and Brief Profile of Mood States. Outcome measures included the Tegner activity scale, International Knee Documentation Committee (IKDC) Subjective Knee Score, Knee injury and Osteoarthritis Outcome Score–Quality of Life subscale (KOOS-QOL), and Short Form–36 (SF-36). Patient charts were also reviewed for pertinent operative details. Results: The mean age of patients (±SD) was 25.7 ± 8.4 years, and the mean duration of time since surgery was 16.5 ± 5.9 months. The majority (89%) of the patients identified themselves as athletes, and of these, 65% reported returning to sports at a competitive level. Sport returners were found to have higher levels of self-esteem (P = .002) and higher reported KOOS-QOL scores (P = .02). Self-esteem was significantly associated with IKDC scores (r = 0.46, P < .05), KOOS-QOL scores (r = 0

  16. Altered Loading in the Injured Knee after ACL Rupture

    PubMed Central

    Gardinier, Emily S.; Manal, Kurt; Buchanan, Thomas S.; Snyder-Mackler, Lynn

    2012-01-01

    Articular loading is an important factor in the joint degenerative process for individuals with anterior cruciate ligament (ACL) rupture. Evaluation of loading for a population that exhibits neuromuscular compensation for injury requires an approach which can incorporate individual muscle activation strategies in its estimation of muscle forces. The purpose of this study was to evaluate knee joint contact forces for patients with ACL deficiency using an EMG-driven modeling approach to estimate muscle forces. Thirty (30) athletes with acute, unilateral ACL rupture underwent gait analysis after resolving range of motion, effusion, pain and obvious gait impairments. Electromyography was recorded bilaterally from 14 lower extremity muscles and input to a musculoskeletal model for estimation of muscle forces and joint contact forces. Gait mechanics were consistent with previous reports for individuals with ACL-deficiency. Our major finding was that joint loading was altered in the injured limb after acute ACL injury; patients walked with decreased contact force on their injured knee compared to their uninjured knee. Both medial and lateral compartment forces were reduced without a significant change in the distribution of tibiofemoral load between compartments. This is the first study to estimate medial and lateral compartment contact forces in patients with acute ACL rupture using an approach which is sensitive to individual muscle activation patterns. Further work is needed to determine whether this early decreased loading of the injured limb is involved in the development of osteoarthritis in these patients. PMID:23097309

  17. Functional results from reconstruction of the anterior cruciate ligament using the central third of the patellar ligament and flexor tendons☆

    PubMed Central

    de Souza Leao, Marcos George; Pampolha, Abelardo Gautama Moreira; Orlando Junior, Nilton

    2015-01-01

    Objectives To evaluate knee function in patients undergoing reconstruction of the anterior cruciate ligament (ACL) using the central third of the patellar ligament or the medial flexor tendons of the knee, i.e. quadruple ligaments from the semitendinosus and gracilis (ST-G), by means of the Knee Society Score (KSS) and the Lysholm scale. Methods This was a randomized prospective longitudinal study on 40 patients who underwent arthroscopic ACL reconstruction between September 2013 and August 2014. They comprised 37 males and three females, with ages ranging from 16 to 52 years. The patients were numbered randomly from 1 to 40: the even numbers underwent surgical correction using the ST-G tendons and the odd numbers, using the patellar tendon. Functional evaluations were made using the KSS and Lysholm scale, applied in the evening before the surgical procedure and six months after the operation. Results From the statistical analysis, it could be seen that the patients’ functional capac