Early outcomes of THA using uncemented dual-mobility cups with additional fixation screws

Background: The use of fixation screws with uncemented cups is controversial particularly for dual mobility (DM) cups where perforation of the articular surface could compromise implant longevity. We aimed to compare outcomes of total hip arthroplasty (THA) using uncemented DM cups with supplementary screw fixation versus simple press-fit fixation. Methods: From 235 consecutive THAs performed using uncemented DM cups, 203 were fixed by simple press-fit and 32 fixed with additional screws. The Oxford hip score (OHS) and EuroQol 5 Dimensions (EQ-5D) score were available at 3.3±1.1 years. To enable direct comparison, each screw fixation cup was matched to three simple press-fit cups using propensity scores, based on age, sex and bone quality. Results: The two groups had equivalent age, body mass index, gender distribution, femoral morphology and bone quality. Compared to the press-fit group (n=96), the screw fixation group had more surgical antecedents (p=0.032), higher femoral neck angles (p=0.028), and received slightly larger cups (p=0.036). Revision was required for two (6%) screw fixation cups (only one implant-related) and one (1%) press-fit cup (none implant-related). There were no differences between OHS (19±8 vs 18±7, p=0.682) nor EQ-5D (0.63±0.37, p=0.257). Conclusions: Revision rates were greater for DM cups fixed with additional screws than for those fixed by simple press-fit, but clinical scores were equivalent. There was only one implant-related revision (acetabular fracture) in the screw fixation group and it is unclear whether this is related to the additional screws or to patient/surgical factors

Etude comparative de la reconstruction du ligament croisé antérieur avec et sans assistance fluoroscopique (étude d'une série de 73 cas (Travail du Service de Chirurgie Orthopédique et Traumatologique et de Médecine du Sport - Pr B Moyen - Pr. J.L. Lerat - Centre Hospitalier Lyon-Sud))

LYON1-BU Santé (693882101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Cinématique des prothèses totales de genou à plateau mobile

Ce travail rapporte la cinématique post opératoire et à plus long terme des prothèses totales de genou conservant le ligament croisé postérieur et à plateau mobile. Pour cela, les clichés radiographiques post opératoires ont été numérisés, les modèles 3D CAD de la prothèse ont été générés pour le logiciel Kneetrack®. La première étape de ce travail a consisté à valider le protocole expérimental. Puis l analyse cinématique en tant que telle a été conduite. Elle s est divisée en trois études : la laxité sagittale intra prothétique post opératoire, la cinématique globale de l implant à divers degré de flexion, et enfin, grâce à la présence de marqueurs métalliques au sein des plateaux mobiles, la cinématique propre du plateau mobileWe report post operative and mid term kinematics of mobile bearing total knee arthroplasty (MB-TKA). The radiographic images were digitized using a high-resolution scanner. The 3-dimensional position and orientation of the implant components were determined using model-based shape-matching techniques. First, effects of radiograph projection parameter uncertainty on TKA kinematics from model-image registration were analyzed. Then, we performed three studies: Sagittal laxity after posterior cruciate ligament found when retaining MB-TKA , Kinematics of a cementless MB PCR-TKA , and finally, with 3D models of the metallic beads inserted in the PE insert, we studied Mobile-bearing kinematics in PCL-retaining TKALYON1-BU.Sciences (692662101) / SudocSudocFranceF

Etude rétrospective d'une série continue de 83 prothèses totales du genou à plateau mobile avec conservation du LCP ou ultra congruentes à 10 ans de recul (évaluation clinique et radiologique)

LYON1-BU Santé (693882101) / SudocSudocFranceF

Growth disturbances without growth arrest after ACL reconstruction in children

Growth arrest is a major concern after ACL reconstruction in children. It usually occurs in patients near to closure of the growth plates. Growth disturbances without growth arrest are also possible and more vicious; the authors analyse the mechanism of two patients with growth disturbance due to overgrowth following ACL reconstruction. One was a symmetrical overgrowth process with 15 mm limb length discrepancy treated with percutaneous epiphysiodesis. Full correction at the time of skeletal maturity was achieved. The second patient developed an asymmetrical overgrowth with progressive tibial valgus deformity. This mechanism was similar to a posttraumatic tibial valgus deformity. After nonoperative treatment, a spontaneous correction of the deformity was noticed. Both children were young (7 and 10 years old) at the time of ACL reconstruction with an autologous iliotibial band graft. The clinical relevance of overgrowth disturbance is usually limited when compared to growth arrest but could require a second surgical procedure as reported in this study. Parents must be informed that even in experienced hands, and despite the use of a physeal sparing technique, this specific risk of growth disturbance is still present

In vitro analysis of patellar kinematics: validation of an opto-electronic cinematic analysis protocol

Opto-electronic cinematic analysis has already proven useful in the investigation of patients with a knee replacement; however, neither patellar tracking nor the various positional parameters relevant to instability such as patellar tilt and/or patellar shift have ever been specifically evaluated using this type of system. The aim of this research was to validate the relevance of this type of cinematic analysis in order to use it in the evaluation of the main factors underlying patellar instability. Six fresh-frozen anatomical specimens were studied. The data were acquired using the Motion Analysis system. Statistical analysis reveals a good reproducibility of measurements. Our protocol based on an opto-electronic acquisition system has an accuracy of 0.23 mm for shift and of 0.4 for rotation, which is calculated by integrating the various experimental parameters and instrumental features specific to the Motion Analysis system. The results are consistent with published results which further attests to the validity and the efficacy of the protocol and encourages us that this protocol is suitable for the in vitro study of patellar kinematics

Patellar fracture after anterior cruciate ligament reconstruction using a bone patellar tendon bone transplant: A comparative study of two harvesting techniques

PURPOSE OF THE STUDY: We studied the incidence and the impact of patellar fracture after anterior cruciate ligament (ACL) reconstruction, comparing two harvesting techniques. MATERIAL AND METHODS: Series A included Kenneth Jones ligamentoplasties (n=1234). The distal and central part of the patella were harvested using an oscillating saw and a gouge. Series B included 676 Mac InJones reconstructions performed during the same period. The patellar cut was done from porximal to distal its attachment were harvested with a manual wire saw. The bony harvesting site was filled with cancellous bone. RESULTS: There were three postoperative transversal patellar fractures (0.24%), all in series A. Functional outcome was disappointing but there was no impact on knee stability. DISCUSSION: The fact that the Mac InJones technique does not involve a transversal cut would apparently prevent secondary fracture

Medial patellofemoral ligament anatomy: implications for its surgical reconstruction

The purpose of the present study, based on 23 cadaveric knees, was to perform a detailed anatomical analysis of the medial patellofemoral ligament (MPFL), especially its femoral attachment, its relationships with the vastus medialis obliquus (VMO) and the medial collateral ligament, with the objective of improving its surgical reconstruction. The femoral insertion of the MPFL was defined using an orthonormal frame centered on the middle of the femoral MPFL insertion. The whole measurements were taken using a millimetric compass with a precision of +/-1 mm. The MPFL was always observed, its length was 57.7 +/- 5.8 mm, the junction between the VMO and the MPFL always present measured 25.7 +/- 6.0 mm. When it comes to MPFL reconstruction, the key point is its positioning in the femoral insertion because it is this insertion that is going to restore isometry. By using the orthonormal frame it has to be positioned 10 mm behind the medial epicondyle and 10 mm distal to the adductor tubercle

Patellar tendon autograft reconstruction of the anterior cruciate ligament with and without lateral plasty in advanced-stage chronic laxity. A clinical, prospective, randomized, single-blind study using passive dynamic X-rays

PURPOSE: A prospective randomized study was performed to assess the influence of extra-articular ilio-tibial band tenodesis on the results of arthroscopic anterior cruciate ligament (ACL) reconstruction in patients with advanced-stage chronic anterior laxity of the knee. METHODS: Preoperatively, the two constituent groups of our series of 120 patients: group 1 (Kenneth Jones) and group 2 (Kenneth Jones+extra-articular ilio-tibial band tenodesis) were strictly comparable with regard to demographic data, activity level, interval between the injury and the operation, and even objective laxity. Through radiological measurements made by passive dynamic X-rays, we studied the evolution of the objective laxity on the two compartments (medial and lateral) of the knee before the surgery and in review. RESULTS: At 2 years follow-up, there was no significant difference between the two groups in terms of the subjective result, sports, and the overall international knee documentation committee score, however, In terms of objective laxity; Gain laxity obtained after surgery on the lateral compartment, was statistically higher in cases of extra-articular associated plasty (+29%), by cons in cases of intra-articular reconstruction alone, the laxity of the lateral compartment was poorly controlled and has continued to evolve despite the plasty of the ACL. CONCLUSION: The indication of an associated extra-articular plasty remains very discussed but we plead for an objective criterion with knowing the importance of preoperative objective laxity especially that of the lateral compartment to decide if it necessary, or not, being associated. LEVEL OF EVIDENCE: Level I, therapeutic prospective randomized trial

Sagittal Laxity After Posterior Cruciate Ligament-Retaining Mobile-Bearing Total Knee Arthroplasty

Posterior cruciate ligament stretching after posterior cruciate ligament-retaining (CR) total knee arthroplasty (TKA) can lead to an increase in sagittal laxity, knee dysfunction, or accelerated damage to the tibial bearing surface. We conducted a prospective study on 74 consecutive mobile-bearing CR TKA to determine if knee laxity changed with time or if knees with large initial laxity experienced greater increases in laxity. Patients were studied with radiographic posterior and anterior drawer examinations at 3 and 23 months. Model-based shape-matching techniques were used to measure TKA kinematics. We found a 1-mm increase in posterior drawer. Knees with large postoperative drawers did not exhibit increased laxity at last follow-up. The use of a mobile-bearing CR TKA did not significantly modify the midterm knee sagittal laxity