Philippe Neyret

University of Lyon, Lyons, Rhône-Alpes, France

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Publications (145)261.27 Total impact

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    ABSTRACT: Numerous surgical techniques have been developed to treat osteochondral defects of the knee. A study reported encouraging outcomes of third-generation autologous chondrocyte implantation achieved using the solid agarose-alginate scaffold Cartipatch(®) . Whether this scaffold is better than conventional techniques remains unclear. This multicenter randomized controlled trial compared 2-year functional outcomes (IKDC score) after Cartipatch(®) versus mosaicplasty in patients with isolated symptomatic femoral chondral defects (ICRS III-IV) measuring 2.5 cm(2) to 7.5 cm(2) . In addition, a histological evaluation based on the O'Driscoll score was performed after 2 years. We needed 76 patients to demonstrate an at least 10-point subjective IKDC score difference with α = 5% and 90% power. During the enrolment period we were able to include 55 patients, 30 of them were allocated at random to Cartipatch(®) and 25 to mosaicplasty. After 2 years, 8 patients had been lost to follow-up, 6 in the Cartipatch(®) group and 2 in the mosaicplasty group. The baseline characteristics of the two groups were not significantly different. The mean IKDC score and score improvement after 2 years were respectively 73.7 ± 20.1 and 31.8 ± 20.8 with Cartipatch(®) and 81.5 ± 16.4 and 44.4 ± 15.2 with mosaicplasty. The 12.6-point absolute difference in favor of mosaicplasty is statistically significant. Twelve adverse events were recorded in the Cartipatch(®) group against 6 in the mosaicplasty group. After 2 years, functional outcomes were significantly worse after Cartipatch(®) treatment compared to mosaicplasty for isolated focal osteochondral defects of the femur. This article is protected by copyright. All rights reserved.
    No preview · Article · Jan 2016 · Journal of Orthopaedic Research

  • No preview · Article · Nov 2015 · Revue de Chirurgie Orthopédique et Traumatologique

  • No preview · Article · Nov 2015 · Revue de Chirurgie Orthopédique et Traumatologique

  • No preview · Article · Nov 2015 · Revue de Chirurgie Orthopédique et Traumatologique

  • No preview · Article · Sep 2015 · Knee Surgery Sports Traumatology Arthroscopy
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    ABSTRACT: Purpose: The purpose of this study was to determine the test-retest reliability and the repeatability over multiple days of a robotic testing device when used to measure laxity of the lower leg during a simulated dial test. Methods: Ten healthy subjects were evaluated using an instrumented robotic lower leg testing system over 4 days. Three testing cycles were performed each day. Each leg was rotated into external and then internal rotation by servomotors until a torque threshold of 5.65 N m was reached. Load-deformation curves were generated from torque and rotation data. Both average-measure and single-measure intraclass correlation coefficients (ICC) were compared across the curves. ICC scores were also compared for features of the curves including: maximum external rotation at -5.65 N m of torque, maximum internal rotation at 5.65 N m of torque, rotation at torque 0, compliance (slope of load-deformation curve) at torque 0, endpoint compliance in external rotation, endpoint compliance in internal rotation, and play at torque 0. Play at torque 0 was defined as the width of the hysteresis curve at torque 0. Results: Average-measure ICC scores and test-retest scores were >0.95 along the entire load-deformation curve except around zero torque. ICC scores at maximum internal and external rotation ranged from 0.87 to 0.99 across the left and right knees. ICC scores for the other features of the curves ranged from 0.61 to 0.98. The standard error of the mean ranged from 0.0497 to 1.1712. Conclusions: The robotic testing device in this study proved to be reliable for testing a subject multiple times both within the same day and over multiple days. These findings suggest that the device can provide a level of reliability in rotational testing that allows for clinical use of test results. Objective laxity data can improve consistency and accuracy in diagnosing knee injuries and may enable more effective treatment.
    Full-text · Article · Sep 2015 · Knee Surgery Sports Traumatology Arthroscopy
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    ABSTRACT: The purpose of this study was to compare the biomechanical characteristics and patient outcomes after either isolated intraarticular ACL reconstruction or intraarticular reconstruction with lateral extra-articular tenodesis. In addition, we aimed to evaluate biomechanical parameters of the entire uninjured, contralateral knee as a baseline during the analysis. Eighteen patients were evaluated at an average of 9.3 years after ACL reconstruction. Twelve patients had an intraarticular reconstruction (BTB), and six had an additional lateral extraarticular procedure (BTB/EAR). Patients were selected for the additional procedure by the operating surgeon based on clinical and radiological criteria. At the time of review, each patient was assessed using subjective patient questionnaires, manual laxity testing, and instrumented laxity testing. Each knee was also evaluated using a robotic lower leg axial rotation testing system. This system measured maximum internal and external rotations at 5.65 Nm of applied torque and generated load deformation curves and compliance data. Pointwise statistical comparisons within each group and between groups were performed using the appropriate paired or unpaired t test. Features were extracted from each load deformation curve for comparative analysis. There were no significant differences between the two groups with respect to the patient satisfaction scores or to laxity testing (manual or instrumented). Robotic testing results for within-group comparisons demonstrated a significant reduction in maximum external rotation (8.77°) in the reconstructed leg when compared to the healthy leg (p < 0.05) in the BTB/EAR group, with a non-significant change in internal rotation. The slope of the curve at maximum internal rotation was also significantly greater in the reconstructed legs for the BTB/EAR group (p < 0.05), indicating reduced endpoint compliance or a harder endpoint. Finally, the leg that received the extra-articular tenodesis had a trend towards a reduced total leg axial rotation. Conversely, patients in the BTB group demonstrated no significant differences between their legs. For between-group comparisons, there was a significant increase in maximum internal rotation in the healthy legs in the BTB/EAR group compared with the healthy legs in the BTB group (p < 0.05). If the injured/reconstructed legs were compared, the significant difference at maximum internal rotation disappeared (p < 0.10). Similarly, the healthy legs in patients in the BTB/EAR group had a significantly more compliant or softer endpoint in internal rotation, greater maximum internal rotation, and more internal rotation at torque 0 in their healthy legs compared with the healthy legs in the BTB group (p < 0.05). These same differences were not noted in the reconstructed knees. The only identifiable significant difference between the injured/reconstructed legs was rotation at 0 torque (p < 0.05). In this group of patients who were at an average of 9 years from surgery, the addition of a lateral extra-articular reconstruction to a standard bone-tendon-bone intraarticular ACL reconstruction does reduces internal rotation of the tibia with respect to the femur when compared to intraarticular reconstruction alone. It appears that the selection process for inclusion into the BTB/EAR group included an increase in total axial rotation of the healthy knee during the examination along with a decrease in endpoint stiffness at maximum internal rotation. II.
    Full-text · Article · Sep 2015 · Knee Surgery Sports Traumatology Arthroscopy
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    ABSTRACT: When performing total knee arthroplasty (TKA) in valgus knee deformities, a medial or lateral parapatellar approach can be performed, but the lateral approach is often considered technically more difficult. The purpose of this study was to compare intra-operative, early clinical and radiological outcomes of medial and lateral parapatellar approaches for TKA in the setting of moderate knee valgus (<10°). We prospectively analysed 424 knees with pre-operative valgus deformity between 3° and 10° that underwent TKA over an 18-year period; 109 were treated with a medial approach and 315 with a lateral approach. Intra- and post-operative outcomes and complication rates after a minimum follow-up of one year were compared. Tourniquet (p = 0.25) and surgical (p = 0.62) time were similar between groups. The popliteus tendon was released more frequently in the medial-approach group (p = 0.04), while the iliotibial band was released more frequently in the lateral-approach group (p < 0.001). A tibial tuberosity osteotomy was performed more frequently in the lateral- than medial-approach group (p = 0.003). No significant differences in limb alignment (p = 0.78), or Knee Society Score (KSS) knee (p = 0.32) and function (p = 0.47) results were noted based on surgical approach, and complication rates were similar between groups (p = 0.53). Lateral parapatellar approach is a safe and effective surgical technique for performing TKA in moderately valgus knees. These equivalent early results are encouraging for systematic use of the lateral approach in moderately valgus knees.
    Full-text · Article · Jul 2015 · International Orthopaedics
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    ABSTRACT: Revision surgery for failed unicompartmental knee arthroplasty (UKA) with bone loss is challenging. Several options are available including cement augmentation, metal augmentation, and bone grafting. The aim of the present study was to describe a surgical technique for lateral tibial plateau autografting and report mid-term outcomes. Eleven consecutive patients (median age 69.5 years) affected by posteromedial tibial plateau collapse after medial UKA were enrolled in the present study. The delay between UKA and revision surgery was 21 months (range 15-36 months). All patients were revised with a cemented posterior-stabilized implant, with a tibial stem. Medial tibial plateau bone loss was treated with an autologous lateral tibial plateau bone graft secured with two absorbable screws. All patients were evaluated with the Oxford Knee Score (OKS), visual analogue scale for pain (VAS), and complete radiographic evaluation. At a median follow-up of 60 months (range 36-84 months), the OKS improved from 21.5 (range 16-26) to 34.5 (range 30-40) (p < 0.01) and the median VAS score improved from 8.0 (range 5-9) to 5.5 (range 3-7) (p < 0.01). No intraoperative complications were recorded. Partial reabsorption of the graft was observed in two cases at final follow-up. Lateral tibial plateau bone autograft is an alternative to metal wedge or cement augments in the treatment of medial plateau collapse after UKA. Primary fixation of the tibial plateau autograft can be achieved with absorbable screws and a tibial-stemmed implant. Further comparative studies with a larger series may be helpful to draw definitive conclusions. Case series, Level IV.
    No preview · Article · Apr 2015 · Knee Surgery Sports Traumatology Arthroscopy
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    Jonathan Robin · Philippe Neyret
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    ABSTRACT: Patellofemoral instability, also referred to as episodic patella dislocation (EPD), occurs at an incidence of 7 per 100,000 people across all age groups. Many anatomical factors are known to contribute to EPD. The most common of these are trochlea dysplasia and patella alta. Patella alta is increasingly being recognized as a main contributing factor in EPD. This morphologic abnormality exists when the patella is located in an exaggerated proximal position such that it does not engage in the trochlea appropriately. The exact biomechanical mechanism that links patella alta to EPD is unclear, but it is likely to be multifactorial. A delay in patellofemoral contact and engagement predisposes to patella dislocation and potentially increased rates of patellofemoral osteoarthritis. Surgical management of patella alta in the setting of EPD aims to restore patella height and patella tendon length back to normal indices. The goal is to improve patellofemoral engagement and prevent further patella dislocations. The recommended procedures include a distalizing tibial tubercle osteotomy and patella tendon tenodesis, which are frequently combined with other procedures to stabilize the patella. Overall, excellent surgical results have been recorded for these procedures in the short term to medium term.
    Preview · Article · Apr 2015 · Operative Techniques in Sports Medicine
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    ABSTRACT: This study aimed to assess the benefit of using an arthroscopic intercondylar view and a posterior medial viewing portal during anterior cruciate ligament (ACL) reconstruction in the diagnosis of posterior horn of the medial meniscus (PHMM) tears. A secondary objective was to determine clinical and radiological risk factors for the PHMM. Forty-one patients undergoing isolated ACL reconstruction were prospectively evaluated. At ACL reconstruction, the PHMM was assessed using a standard 30° arthroscope in 3 sequential stages: a "classic" anterolateral portal view, an intercondylar view, and a view through a posteromedial portal. Thirty-nine patients were included (12 female patients and 27 male patients). A posteromedial tear of the medial meniscus was found in 17 patients using the anterolateral portal view. The intercondylar view identified 4 new additional lesions and extensions of 3 previously identified lesions. The posteromedial portal view identified 6 new lesions and 5 extensions of known lesions compared with the anterolateral portal view. Two lesions seen through the posteromedial portal were not identified by either the anterolateral portal view or the intercondylar view. Tears of the PHMM may be underdiagnosed by intraoperative assessment using only an anterolateral portal view during ACL reconstruction. The intercondylar view combined with a posteromedial portal aids in the diagnosis of PHMM tears and should be considered in routine ACL reconstruction to assess meniscal status, particularly when the interval from injury to surgery is prolonged. Level IV, therapeutic case series. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
    No preview · Article · Feb 2015 · Arthroscopy The Journal of Arthroscopic and Related Surgery
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    ABSTRACT: Abstract PURPOSE: While many studies about anterior-cruciate-ligament-deficient (ACLD) patients have demonstrated functional adaptations to protect the knee joint, an increasing number of patients undergo ACL reconstruction (ACLR) surgery in order to return to their desired level of activity. The purpose of this study was to compare 3D kinematic patterns between individuals having undergone ACLR with their healthy contralateral knee and a control group. METHODS: Three-dimensional kinematic data were obtained from 15 patients pre- and post-ACLR, 15 contralateral knees and 15 healthy controls. Data were recorded during treadmill walking at self-selected speed. Flexion/extension, external/internal tibial rotation, adduction/abduction and anterior/posterior tibial translation were compared between groups. RESULTS: ACLR knees showed a significantly higher knee-joint extension during the entire stance phase compared with ACLD knees. However, ACLR knees still showed a deficit of extension compared with healthy control knees. In the axial plane, there was no significant difference in pre- and postoperative kinematic data. Significant difference was achieved between ACLR knees and healthy control knees, specifically between 28 and 34 % and 44 and 54 % of the gait cycle. There was no significant difference in anterior-posterior translation or coronal plane between groups. CONLUSION: Following ACL reconstruction, patients have better clinical and kinematic parameters. Despite improvements, knee kinematics during gait in the ACLR group differed from the control group. These kinematic changes could lead to abnormal loading in the knee joint and initiate the process for future chondral degeneration.
    No preview · Article · Dec 2014 · International Orthopaedics
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    ABSTRACT: Dear Editor,We appreciate the valuable comments and constructive suggestions regarding our paper. We have carefully considered the comments and respond accordingly [1].The femoral mechanical axis is represented by the line passing through the centre of the femoral head and the middle of the tibial spines. The angle described in our study represents the angle between this axis and the tangent line of the femoral condyles. The tibial mechanical axis is represented by the line passing by the middle of the tibial spines and the middle of the tibial plafond. The angle described in our study represents the angle between this axis and the tangent line of the healthy tibial plateau. This method allows evaluation of the extra-articular part of the deformity. We can also use the Dejour and Levigne method to measure the tibial epiphyseal angle [2]. The mechanical femorotibial axis is the angle between the two aforementioned axes.Indeed, we have not completely described the surgical technique. ...
    No preview · Article · Dec 2014 · International Orthopaedics

  • No preview · Article · Nov 2014 · Revue de Chirurgie Orthopédique et Traumatologique
  • Robert A. Magnussen · Diane L. Dahm · Philippe Neyret
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    ABSTRACT: Anterior cruciate ligament (ACL) injury and its subsequent reconstruction are increasingly common. Numerous authors have stressed that successful revision ACL reconstruction depends on identification and treatment of the reason for failure of the primary reconstruction. Relatively little attention has been paid to the influence of tibial slope on stability and the need for ACL revision. The goal of this chapter is to explore the role of tibial deflexion osteotomy in improving the outcome of revision ACL reconstruction. We recommend addressing tibial slope in patients with a posterior tibial slope greater than 13°who are undergoing revision ACL reconstruction. The technique described below involves the use of an anterior closing-wedge osteotomy to decrease tibial slope. This procedure may improve outcomes in carefully selected patients, although current research is quite limited. Further work is needed to confirm the utility of this approach and more clearly define indications. © Springer Science+Business Media New York 2014. All rights are reserved.
    No preview · Chapter · Nov 2014
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    ABSTRACT: Introduction: The literature results of unicompartmental knee arthroplasty (UKA) for isolated lateral osteoarthritis (OA) are not as good as for isolated medial OA. In 1988 our department started using a UKA with a fixed, all polyethylene tibial component and a resurfacing femoral component. The aim of this retrospective study is to report on the progression of medial OA and the long term results of this prosthesis implanted for isolated lateral OA, at a minimum follow up of ten years. Materials and methods: From January 1988 to October 2003, we performed 54 lateral UKAs in 52 patients. All patients had isolated lateral OA, which was post-traumatic in three cases. The mean age at the time of the index procedure was 72.2 ± 15.2 years. Forty-six UKAs in 44 patients were available for follow-up. The mean duration of follow-up was 14.2 years (minimum ten years; range 10.2-18 years). Results: At final follow-up, seven had undergone a second operation, three were revised to total knee arthroplasty (TKA), three had medial UKAs implanted for progression of medial disease, and one was converted to TKA for tibial tray malpositioning. No revision surgery was necessary for wear, infection or progression of patellofemoral OA. The mean Knee Society Score (KSS) knee score was 95.1 points and mean KSS function score was 82.2 points. The mean range of motion was 132.6° (range, 115-150°). Implant survival was 94.4% at ten years and 91.4% at 15 years. Conclusion: The use of a UKA with a fixed, all polyethylene tibial bearing and a femoral resurfacing implant is a reliable option for the management of isolated lateral knee osteoarthritis. We have demonstrated excellent functional results and implant survival in the long term. The most significant factor leading to reoperation is progression of medial disease.
    No preview · Article · Sep 2014 · The Knee
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    ABSTRACT: Purpose: Medial structures repair is a well-established approach in the treatment for patellar instability. However, the literature is confusing concerning the indications for surgery, the different surgical techniques and outcomes. The goal of this systematic review was to clarify the indications for medial structures repair and to analyse the results of both arthroscopic and open techniques. Methods: A comprehensive literature review was performed using the keywords 'patellar instability', 'medial capsule reefing' and 'medial capsule plication' with no limit regarding the year of publication. All the selected articles in Anglo-Saxon language were evaluated with the Coleman methodology score. Results: Seventeen full-text articles were evaluated. Initial cohort included 617 patients. About 569 patients were reviewed at an average FU of 54.6 months (range 2-165 months) after medial structures repair. Average age at the time of surgery was 21.2 years (range 9-65 years). The indications for surgery included both patellar subluxation and dislocation (acute or chronic). Average Kujala score increased from 55 to 84 at the last FU, and in the same way average Lysholm score increased from 41.2 to 80.5, whereas average Tegner score increased from 3 to 5.3 and IKDC score from 47.8 to 75.1. Re-dislocation rate among the series was 6.1%. Average Coleman methodology score was 61.6 (range 17-92). Conclusion: From this review, it emerges that medial capsule reefing is a reliable option in the treatment for patellar instability. It can be proposed with good expectations, since the outcomes are positive and stable even at longer FU and complications rates are low. Re-dislocation rate is variable and can occur in up to one-third of patients. However, most of the available studies are case series, and comparison of the series is hard since they widely differ in inclusion criteria and indications, surgical technique and additional procedures, and outcome measures.
    No preview · Article · Jul 2014 · Knee Surgery Sports Traumatology Arthroscopy
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    ABSTRACT: Purpose Long-term survival in total knee arthroplasty (TKA) depends on multiple factors, including restoration of mechanical alignment and obtaining optimal ligament balance. The aim of this study was to document the results of single-stage TKA combined with high tibial osteotomy for managing femorotibial arthrosis with significant frontal-plane deformity. Methods Patients with osteoarthritis of the knee and extra-articular deformity in > 10° and operated between 1997 and 2001 were reviewed retrospectively. In each case, a high tibial osteotomy combined with a posterior stabilised TKA was performed. Patients were assessed using the Knee Society Score (KSS). The femorotibial mechanical angle was measured on radiographs pre- and postoperatively and at the most recent follow-up. Results Fifteen knees in 12 patients were included in the study. Mean age was 68.2; average follow-up was 78 months (22.1–145.9). The KSS improved significantly from 47.1 (28–58) to 60.7 (40–94) points (p
    No preview · Article · Jun 2014 · International Orthopaedics
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    ABSTRACT: Purpose: Opening wedge high tibial osteotomy (HTO) is an accepted treatment option for medial compartment knee osteoarthritis with associated varus lower limb axis in younger, more active patients. A concern with the use of this technique is that posterior tibial slope (PTS) and tibial rotation can be altered. We hypothesized that there is a tendency to increase the PTS and internal rotation of the distal tibia during the procedure and that certain intra-operative parameters may influence the amount of change that can be expected. Methods: A cadaveric model and surgical navigation system were used to evaluate the influence of certain intra-operative factors of the degree of PTS and tibial rotation change observed during medial opening HTO. Parameters evaluated included: degree of osteotomy opening, knee flexion angle, location of limb support (thigh versus foot), performance of a posteromedial release, the status of the lateral cortical hinge, and the degree of osteoarthritis present in the knee. Results: Combining measurements of all specimens and parameters, a mean PTS increase of 2.7° ± 3.9° and a mean tibial internal rotation of 1.5° ± 2.9° were observed. Clinically, significant changes in tibial slope (>2°) occurred in 50.4 % of corrections, while significant changes in tibial rotation (>5°) occurred in only 11.9 % of corrections. Patients with significant osteoarthritis and concomitant flexion contracture, cases where large corrections were required, and procedures in which the lateral cortical hinge was disrupted were associated with increased PTS change. The other factors evaluated did not exert a significant influence of the degree of PTS change observed. Conclusions: Surgeons should be vigilant for possible PTS change, particularly in high-risk situations as outlined above. Routine use of an intra-operative measure of PTS is recommended to avoid inadvertent slope change.
    No preview · Article · Jun 2014 · Knee Surgery Sports Traumatology Arthroscopy
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    ABSTRACT: 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 2,286 patients undergoing revision anterior cruciate ligament reconstruction (ACLR) were obtained. These data included 1,216 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 (Knee Injury and Osteoarthritis Outcome Score, subjective International Knee Documentation Committee), 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 favoured in the NKRL, while bone–patellar tendon–bone autograft was most common in the SFA cohort. Reasons for failure of the primary ACLR were comparable, with recurrent trauma noted in 46–56 % of patients in each of the three cohorts. Technical error was cited in 44–51 % 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. Level of evidence Retrospective comparative study, Level III.
    Full-text · Article · May 2014 · Knee Surgery Sports Traumatology Arthroscopy

Publication Stats

2k Citations
261.27 Total Impact Points

Institutions

  • 2011-2015
    • University of Lyon
      Lyons, Rhône-Alpes, France
    • Imperial College London
      Londinium, England, United Kingdom
  • 2008-2015
    • Hospices Civils de Lyon
      Lyons, Rhône-Alpes, France
  • 2000-2015
    • CHU de Lyon - Hôpital de la Croix-Rousse
      Lyons, Rhône-Alpes, France
  • 2012
    • HCL
      Noida, Uttar Pradesh, India
  • 2011-2012
    • CHU de Lyon - Groupement Hospitalier Edouard Herriot
      Lyons, Rhône-Alpes, France
  • 2010
    • University of Lille Nord de France
      Lille, Nord-Pas-de-Calais, France