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Robert F. Laprade - One of the best experts on this subject based on the ideXlab platform.

  • clinical outcomes of high tibial osteotomy for Knee Instability a systematic review
    Orthopaedic Journal of Sports Medicine, 2016
    Co-Authors: Chase S Dean, Daniel J Liechti, Jorge Chahla, Gilbert Moatshe, Robert F. Laprade
    Abstract:

    Background:In recent years there has been an increasing interest in high tibial osteotomy (HTO) to treat patients with chronic Knee Instability due to posterolateral corner (PLC), posterior cruciat...

  • the external rotation recurvatum test revisited reevaluation of the sagittal plane tibiofemoral relationship
    American Journal of Sports Medicine, 2008
    Co-Authors: Robert F. Laprade, Thuan V Ly, Chad J Griffith
    Abstract:

    Background:Posterolateral corner injuries can be difficult to diagnose. The external rotation recurvatum test was one of the first clinical tests described to diagnose these injuries. Since its earliest description, it has been reported that a positive test result occurred with posterior translation of the proximal tibia with respect to the distal femur as the Knee went into recurvatum, external rotation, and varus angulation.Purpose:To document the sagittal plane relationship of the tibiofemoral joint in patients with posterolateral Knee Instability and a positive external rotation recurvatum test finding, and to determine possible injury patterns associated with this test.Study Design:Case series; Level of evidence, 4.Materials and Methods:In a series of 134 consecutive patients with posterolateral Knee injuries, all patients demonstrating a Positive external rotation recurvatum test result were identified, and bilateral hyperextension lateral radiographs were subsequently obtained to assist with preope...

  • the effect of a proximal tibial medial opening wedge osteotomy on posterolateral Knee Instability a biomechanical study
    American Journal of Sports Medicine, 2008
    Co-Authors: Robert F. Laprade, Fred A Wentorf, Steinar Johansen, Lars Engebretsen, Chad Kurtenbach
    Abstract:

    BackgroundIncreased stability of posterolateral corner Knee injuries has been observed clinically after proximal tibial medial opening wedge osteotomies.HypothesisStatic varus and external rotatory stability will be significantly improved in a Knee with a grade 3 posterolateral Knee injury after a proximal tibial medial opening wedge osteotomy.Study DesignControlled laboratory study.MethodsBiomechanical testing of 10 nonpaired, cadaveric Knees was performed in the intact state, after transection of the posterolateral corner (fibular collateral ligament, popliteus tendon, and popliteofibular ligament), and after a 10-mm proximal tibial medial opening wedge osteotomy. Loading conditions consisted of 12 N.m varus moments and 6 N.m external rotation torques. Six degrees of freedom motion analysis was used to assess motion changes, and a buckle transducer was used to measure the force on the superficial medial collateral ligament during applied loads.ResultsAfter transection of the posterolateral corner struct...

  • biomechanical analysis of an isolated fibular lateral collateral ligament reconstruction using an autogenous semitendinosus graft
    American Journal of Sports Medicine, 2007
    Co-Authors: Benjamin R Coobs, Robert F. Laprade, Chad J Griffith, Bradley J Nelson
    Abstract:

    BackgroundThe fibular collateral ligament is the primary stabilizer to varus Instability of the Knee. Untreated fibular collateral ligament injuries can lead to residual Knee Instability and can increase the risk of concurrent cruciate ligament reconstruction graft failures. Anatomic reconstructions of the fibular collateral ligament have not been biomechanically validated.PurposeTo describe an anatomic fibular collateral ligament reconstruction using an autogenous semitendinosus graft and to test the hypothesis that using this reconstruction technique to treat an isolated fibular collateral ligament injury will restore the Knee to near normal stability.Study DesignControlled laboratory study.MethodsTen nonpaired, fresh-frozen cadaveric Knees were biomechanically subjected to a 10 N·m varus moment and 5 N·m external and internal rotation torques at 0°, 15°, 30°, 60°, and 90° of Knee flexion. Testing was performed with an intact and sectioned fibular collateral ligament, and also after an anatomic reconstr...

  • an in vivo injury model of posterolateral Knee Instability
    American Journal of Sports Medicine, 2006
    Co-Authors: Robert F. Laprade, Fred A Wentorf, Erik J Olson, Cathy S Carlson
    Abstract:

    Background: Posterolateral Knee Instability is a difficult clinical problem to diagnose and treat. To best evaluate its natural history and the effects of interventional treatments, it is important to develop an in vivo model in an attempt to validate human cadaveric and clinical observational studies.Purpose: To develop an in vivo model of posterolateral Knee Instability in the rabbit and to determine the natural history of untreated posterolateral Knee injuries at 6 months postoperatively.Study Design: Controlled laboratory study.Methods: The fibular collateral ligament and popliteus tendon were surgically transected in 1 Knee in each of 10 skeletally mature New Zealand White rabbits, with the contralateral Knee serving as a control Knee. At 6 months postoperatively, the rabbits were euthanized, the Knees were removed, and biomechanical testing of Knee joint stability was performed. After biomechanical testing, histological sections of each proximal tibia and distal femur were evaluated, and each proxim...

Michael C Nevitt - One of the best experts on this subject based on the ideXlab platform.

  • the association of vibratory perception and muscle strength with the incidence and worsening of Knee Instability the multicenter osteoarthritis study
    Arthritis & Rheumatism, 2017
    Co-Authors: Najia Shakoor, David T Felson, Jingbo Niu, Uyensa D T Nguyen, Neil A Segal, Jasvinder A Singh, Michael C Nevitt
    Abstract:

    OBJECTIVE To examine neuromuscular factors that predict the incidence and progression of Knee Instability symptoms in older adults with or at high risk of Knee osteoarthritis (OA). METHODS At the 60-month clinic visit, participants in the Multicenter Osteoarthritis Study underwent evaluation of quantitative vibratory sense at the Knee and isokinetic quadriceps muscle strength. At this 60-month visit, participants were also asked about Knee buckling and sensations of Knee shifting or slipping without buckling in the past 3 months and then were asked the same questions at the 72- and 84-month follow-up visits. We performed a person-based analysis using Poisson regression analysis with robust error variance to estimate adjusted relative risks (RRs) for the association of vibratory sense and muscle strength with the incidence and worsening of Knee slipping/shifting, buckling, and overall Knee Instability symptoms (either buckling or Knee shifting/slipping), with adjustment for relevant confounders. RESULTS A total of 1,803 participants (61% women) were included. Approximately one-third of the participants reported incident or worsening of Instability symptoms over the study period. After adjustment for relevant confounders, better vibratory acuity (adjusted RR 0.78, 95% confidence interval [95% CI] 0.56-1.09), P = 0.020 for trend) and greater quadriceps strength (adjusted RR 0.53, 95% CI 0.38-0.75, P < 0.001) protected against incident Knee Instability symptoms. Greater quadriceps strength (adjusted RR 0.73, 95% CI 0.58-0.92, P = 0.008) also protected against worsening of Knee Instability symptoms. CONCLUSION Vibratory acuity and quadriceps muscle strength are important predictors of the incidence and worsening of Knee Instability over 2 years. These neuromuscular factors are potentially modifiable and should be considered in interventional studies of Instability in persons with or at risk of Knee OA.

  • symptoms of Knee Instability as risk factors for recurrent falls
    Arthritis Care and Research, 2016
    Co-Authors: Michael C Nevitt, Najia Shakoor, Uyensa D T Nguyen, Neil A Segal, Cora E Lewis, Irina Tolstykh, David T Felson
    Abstract:

    OBJECTIVES: Whether Knee Instability contributes to the increased risk of falls and fractures observed in persons with Knee osteoarthritis (OA) has not been studied. We examined the association of Knee buckling with the risk of falling and fall-related consequences in older adults with, or at high risk for, Knee OA. METHODS: At the 60 month visit of the Multicenter Osteoarthritis Study, men and women ages 55 to 84 were asked about Knee buckling in the past 3 months and whether they fell when a Knee buckled. Falls and fall-related injuries in the past 12 months and balance confidence were assessed at 60 and 84 months. Multivariate logistic regression was used to assess the association of Knee buckling with falls and their consequences. RESULTS: 1,842 subjects (59% women, mean [SD] age= 66.9 [7.8] and BMI= 30.3 [5.7]) were included. At 60 months 16.8% reported buckling and at 84 months 14.1% had recurrent (?2) falls. Bucklers at 60 months had a 1.6 to 2.5-fold greater odds of recurrent falls, fear of falling and poor balance confidence at 84 months. Those who fell when a Knee buckled at baseline had a 4.5-fold, 2-fold and 3-fold increased odds two years later of recurrent falls, significant fall injuries and fall injuries that limited activity, respectively, and were 4 times more likely to have poor balance confidence. CONCLUSION: Interventions that reduce Knee buckling may help prevent falls, fall-related injuries and adverse psychological consequences of falls in persons with Knee OA. This article is protected by copyright. All rights reserved.

  • the impact of Knee Instability with and without buckling on balance confidence fear of falling and physical function the multicenter osteoarthritis study
    Osteoarthritis and Cartilage, 2014
    Co-Authors: Uyensa D T Nguyen, David T Felson, Neil A Segal, Daniel K White, Cora E Lewis, Margaret Rasmussen, Michael C Nevitt
    Abstract:

    Summary Objective Knee buckling, in which a Knee gives way during weight-bearing, is common in people with Knee pain and Knee osteoarthritis (OA), but little is known about the prevalence of sensations of Knee Instability, slipping or shifting in which the Knee does not actually buckle, or of the psychosocial and physical consequences of these symptoms. Design We asked participants in the Multicenter Osteoarthritis Study (MOST) separately about episodes of Knee buckling and sensations of Knee Instability without buckling in the past 3 months, and assessed fear of falling, poor balance confidence (Activities-specific Balance Confidence (ABC) Scale ≤ 67/100), activity limitation due to concern about buckling, and poor physical function (Western Ontario and McMaster Universities Arthritis Index (WOMAC) physical function ≥ 28/68). We used Poisson regression to estimate prevalence ratios (PRs) for cross-sectional associations of buckling and sensations of Instability without buckling with these outcomes, adjusting for confounders. Results Of 2120 participants (60% female, 40% ≥ 65 years, mean Body mass index (BMI): 31 kg/m258), 18% reported buckling, 27% had sensations of Knee Instability without buckling, and 9% reported both symptoms. Buckling and sensations of Instability without buckling were each significantly associated with fear of falling, poor balance confidence, activity limitations, and poor WOMAC physical function. Subjects who reported both buckling and Instability without buckling and those with at least two buckling episodes (15%) had the strongest association with poor outcomes. Conclusions Knee buckling and especially sensations of Knee Instability without buckling were common and each was significantly associated with fear of falling, poor balance confidence, activity limitations, and poor physical function.

  • the association of vibratory sense and muscle strength with the incidence and worsening of Knee Instability the most study
    Osteoarthritis and Cartilage, 2014
    Co-Authors: Najia Shakoor, David T Felson, Neil A Segal, Us Nguyen, J Nui, J Singh, Michael C Nevitt
    Abstract:

    s / Osteoarthritis and Cartilage 22 (2014) S57–S489 S377 ECGs and vital signs were unremarkable and similar across all treatments. Plasma TCA concentration across the FX006 doseswere linear and dose-dependent. Peak plasma concentrations achieved with 40 mg TCA IR were 10X of those seen with FX006 40 mg. Conclusions: It is demonstrated that sustained residency of TCA in the joint prolongs therapeutic effect. The 40 mg dose of FX006 produced an effect atWeek 12 ( 3.7) that was equivalent to the maximal effect of TCA IR at Week 4. Surprisingly, between Weeks 2 and 11, the analgesic effect of the 40mg dose of FX006 exceeded themaximal effect of TCA IR seen at Week 4. This observation suggests that prolonged occupation of the corticosteroid receptor may be associated with an enhanced analgesic effect. Further, this amplification of effect may constitute a meaningful clinical improvement relative toTCA IR as indicated by the 20% responder analysis for the 40 mg dose of FX006. A study is underway to determine the TCA concentrations in the joint at varying time points, and subsequent studies against placebo will define effect size and duration of action. Figure 1. Weekly Mean of Average Daily Pain Score (ADP) Figure 2. Proportion of Responders, >20% Improvement

Christopher Wilson - One of the best experts on this subject based on the ideXlab platform.

  • Knee Instability as the primary cause of failure following total Knee arthroplasty tka a systematic review on the patient surgical and implant characteristics of revised tka patients
    Knee, 2017
    Co-Authors: Christopher Wilson, Annika Theodoulou, Raechel Damarell, Jeganath Krishnan
    Abstract:

    Abstract Background The aim of this review was to systematically assess the current evidence available regarding Knee Instability after TKA to identify time to failure between primary and revision TKA. In addition, we considered the patient, surgical and implant characteristics of primary TKA patients revised for Knee Instability, and investigated methods used for Knee Instability diagnosis. Methods A systematic search of six databases and the unpublished literature was performed. Studies referring to Instability in post-operative primary TKA patients, reporting on revision TKA due to Instability, and published or available between 2005 to 30-Mar-2015 were eligible for inclusion. Quantitative data for continuous variables were pooled in statistical meta-analyses. Results A total of 1841 unique studies were identified, 42 of which met the selection criteria and a total of 22 studies included in the review. Time to failure between primary and revision TKA was 44.7 months (95% CI [33.8, 55.7]), and the weighted mean age at time of revision surgery was 67.6 years (95% CI [65.38, 69.75]). A gender distribution was identified, with approximately 16.4% more females revised for Instability, however this was unable to be corrected for the baseline population. The majority of studies used a combination of radiographic and clinical testing to diagnose Knee Instability. Conclusion Research on Knee Instability following primary TKA reported early failure and subsequent revision Knee surgery. The need for revision due to Instability was frequently reported in a younger patient cohort and most commonly in female TKA patients. Early revision at a younger age highlights the severe implications of an unstable Knee.

Jeganath Krishnan - One of the best experts on this subject based on the ideXlab platform.

  • Knee Instability as the primary cause of failure following total Knee arthroplasty tka a systematic review on the patient surgical and implant characteristics of revised tka patients
    Knee, 2017
    Co-Authors: Christopher Wilson, Annika Theodoulou, Raechel Damarell, Jeganath Krishnan
    Abstract:

    Abstract Background The aim of this review was to systematically assess the current evidence available regarding Knee Instability after TKA to identify time to failure between primary and revision TKA. In addition, we considered the patient, surgical and implant characteristics of primary TKA patients revised for Knee Instability, and investigated methods used for Knee Instability diagnosis. Methods A systematic search of six databases and the unpublished literature was performed. Studies referring to Instability in post-operative primary TKA patients, reporting on revision TKA due to Instability, and published or available between 2005 to 30-Mar-2015 were eligible for inclusion. Quantitative data for continuous variables were pooled in statistical meta-analyses. Results A total of 1841 unique studies were identified, 42 of which met the selection criteria and a total of 22 studies included in the review. Time to failure between primary and revision TKA was 44.7 months (95% CI [33.8, 55.7]), and the weighted mean age at time of revision surgery was 67.6 years (95% CI [65.38, 69.75]). A gender distribution was identified, with approximately 16.4% more females revised for Instability, however this was unable to be corrected for the baseline population. The majority of studies used a combination of radiographic and clinical testing to diagnose Knee Instability. Conclusion Research on Knee Instability following primary TKA reported early failure and subsequent revision Knee surgery. The need for revision due to Instability was frequently reported in a younger patient cohort and most commonly in female TKA patients. Early revision at a younger age highlights the severe implications of an unstable Knee.

Ian W Forster - One of the best experts on this subject based on the ideXlab platform.

  • high tibial osteotomy in Knee Instability the rationale of treatment and early results
    Orthopaedic Proceedings, 2003
    Co-Authors: Nitin P Badhe, Ian W Forster
    Abstract:

    The purpose of this study was to evaluate the role of high tibial osteotomy (HTO) [Lateral closed wedge v/s medial open wedge] in varus aligned Knees with ligament Instability. (ACL, PCL, PLRl). We treated 14 patients with Knee Instability and varus alignment with HTO with or without ligament reconstruction. 5 patients with varus angulated ACL deficiency (double varus) were treated with single stage closed wedge HTO and ACL reconstruction. Of the remaining nine patients with PCL + PLRI injuries with varus angulation (Triple varus), six were treated with LARS ligament reconstruction with HTO, and the remaining were treated with HTO without ligament reconstruction. Four of these patients with triple varus had a open wedge HTO and the remaining five patients had a closed wedge HTO. The mean time interval between injury and index surgery was 8.3 years. At a mean follow-up of 2.8 years 12 Knees (86%) were stable and eliminated of giving way. In one patient the result was compromised with severe infection. Five patients (35%) continued to have varying degree of pain. According to the Cincinnati Knee scoring system there were eight good, four fair and two poor results. In patients with triple varus, open wedge HTO had better scores than closed wedge HTO. The results of this series are encouraging and we recommend HTO with ligament reconstruction in these complex cases.

  • high tibial osteotomy in Knee Instability the rationale of treatment and early results
    Knee Surgery Sports Traumatology Arthroscopy, 2002
    Co-Authors: Nitin P Badhe, Ian W Forster
    Abstract:

    We treated 14 patients having Knee Instability and varus alignment with tibial osteotomy with or without ligament reconstruction. Five patients with varus angulated anterior cruciate deficiency (double varus) were treated with single-stage closed-wedge tibial osteotomy and anterior cruciate ligament reconstruction. The remaining nine patients had varying amount of posterior cruciate and postero-lateral corner ligament injuries with varus angulation (triple varus); six of these patients had a ligament reconstruction using the Ligament Advanced Reconstruction System ligament with tibial osteotomy (intra-articular–posterior cruciate ligament/extra-articular–postero-lateral corner reconstruction), while the remaining three had a tibial osteotomy without a ligament reconstruction. Four of the nine patients with triple varus had open-wedge tibial osteotomy, and the remaining five had closed-wedge tibial osteotomy. The mean time interval between injury and index surgery of an osteotomy and ligament surgery was 8.3 years (range 1–20 years). At a mean follow-up of 2.8 years after tibial osteotomy, 12 Knees (86%) were stable and eliminated of giving way while the remaining 2 were unstable. In one of these patients the result was compromised with severe infection, while in another there was combined cruciate ligament deficiency with postero-lateral corner ligament deficiency. Thirteen (93%) of the patients were able to participate in light recreational activities. None of these patients could return to competitive sports. Five (35%) continued to have pain of varying degree. The mean Cincinnati Knee Score improved from a mean preoperative of 53 (range 40–58) to a mean postoperative of 74 (range 58–82). Accordingly, there were two poor, four fair and eight good results. In-patients with triple-varus, open-wedge tibial osteotomy had better scores than those with closed-wedge procedure. The results of this series are encouraging, and we recommend a high tibial osteotomy along with ligament reconstruction in these complex injuries with varus alignment.