Adult lumbar scoliosis.

This report details the expierience with adult lumbar scoliosis among patients at a scoliosis center. Some curves are shown to progress in the adult, while others appear de novo. Pain arising in adult scoliosis may reflect root compression or segmental degeneration. Once pain arises in an adult lumbar curve, it is likely to be progressive and often requires surgical treatment.

Bone morphing: 3D morphological data for total knee arthroplasty.

OBJECTIVE: The clinical outcome of a total knee arthroplasty (TKA) is mainly determined by the accuracy of the surgical procedure itself. To improve the final result, one must take into account (a) the alignment of the prosthesis with respect to the mechanical axis, and (b) the balance of the soft tissues. Therefore, morphologic data (such as the shape of the epiphysis) and geometric data are essential. We present a new method for performing TKA based on morphologic and geometric data without preoperative images. MATERIALS AND METHODS: The global method is based on the digitization of points with an optical 3D localizer. For the morphologic acquisitions, we use a method based on the registration of sparse point data with a 3D statistical deformable model. To build the mechanical axis, we use a kinematics method for the hip center and digitization of anatomical landmarks for the ankle centers. The knee center is not determined by digitization or kinematics of the knee, as this would not be accurate. The surgical planning relies totally on the soft-tissue balance, which is the key issue for a good kinematics result. RESULTS: We have used this system for 6 months in a randomized clinical trial involving 35 patients to date. For the first 11 patients that could be measured in the navigation group, the postoperative frontal alignment was within the range of 180 +/- 3 degrees. Fluoroscopic assessment of the soft-tissue balancing will be performed at the conclusion of an extended 2-year study to evaluate the results from a functional point of view. CONCLUSION: Bone Morphing is an accurate, fast, and user-friendly method that can provide morphologic as well as geometric data. We have introduced the important notion of soft-tissue balancing into the intraoperative planning step to optimize the kinematics as well as the anatomy. Therefore, this method should be considered as an alternative to the CT-based method.

[Transepiphyseal lengthening of the tibia. Apropos of a case]. / L'allongement trans-épiphysaire du tibia. A propos d'un cas.

Most tibial lengthenings are undertaken at the level of the diaphysis but in some cases this cannot be done and the lengthening can be made at upper epiphyseal level. The technique involves the application of pins in the upper epiphysis and diaphysis fixed by a Hoffman external fixator adapted for progressive distraction. The technique was used in a child of 13 years with 9 cm of shortening and an expected shortening of 13 cm at the end growth. The method has obtained the progressive lengthening of 11 cm and bony union without grafting.

Survival analysis of total knee arthroplasty at a minimum 10 years' follow-up: a multicenter French nationwide study including 846 cases.

INTRODUCTION: Survivorship for modern total knee arthroplasties (TKA) is not precisely known from large series, other than registries. The present retrospective study therefore analyzed 846 TKAs at a minimum 10 years' follow-up. HYPOTHESIS: Ten-year survivorship for TKAs in a multicenter study exceeds 90%, independently of design and level of prosthetic constraint. MATERIALS AND METHODS: Eight hundred and twenty-eight patients (846 TKAs) were assessed on the Knee Society score. Mean age was 71 years (range, 41-93 years); 274 males and 554 females (67%); 496 patients (60%) were active; diagnosis was principally osteoarthritis (n=752 [89%]). Most TKAs were cemented (n=704 [83%]), replacing the patella (n=668 [79%]) and sacrificed the posterior cruciate ligament (PCL) (n=707 [84%]), 65% being posterior-stabilized and 35% ultracongruent, with fixed (39%) or mobile bearing (61%). RESULTS: At a minimum 10 years' follow-up, mean knee score rose from 35 (15-55) to 83 points (74-95), and functional score from 24 (5-45) to 74 points (60-90); mean flexion rose from 105° (25-125°) to 112° (25-125°). Mean hip-knee-ankle angle was 179.5° (169-189°). Sixty-three (7.5%) revision surgeries were required, mainly for loosening (n=18 [2%]) or infection (n=18 [1.8%]). Overall 10-year survivorship was 92% (95% CI: 0.90-0.94). There was no significant difference in survivorship according to implant design or PCL retention. Activity level correlated with revision rate; mechanical complications were more frequent in active and infectious complications in sedentary subjects. Revision was not more frequent in TKA aligned outside the 177-183° range. DISCUSSION: Ten-year TKA survivorship was 92%, independently of design and level of mechanical stress. Revision was mainly for infection or loosening, and not for greater than 3° axis misalignment. Mechanical complications were more frequent in younger and more active subjects, for whom therefore other treatment options or technical improvements should be sought. LEVEL OF EVIDENCE: Level IV. Retrospective study.

[Soft tissue management in total knee replacement. Analysis of ligament balancing]. / Weichteilmanagement in der Knieendoprothetik. Untersuchung der Ligamentbalancierung.

Total knee replacement must provide good function with stability, range of motion and long durability. The easiest part of the surgery concerns bone cuts. It is widely accepted today that the quality of the results mostly relies on the soft tissue management. Intraoperative soft tissue management is still challenging since pre-existing soft tissue quality and bony anatomy have to be respected. The surgeon may have to address the soft tissue to fit with the new alignment and prosthetic mechanics. This challenge must be mastered with correct understanding and use of instruments to quantify these soft tissues. Tensors, distractors, spacer blocks and use of navigation were evaluated, and the authors compared these methods. The parameters for better use of soft tissues are described. Objective measurements are still difficult due to the pre-operative conditions that influence measurement accuracy.

Patellofemoral instability in total knee arthroplasty.

Patellofemoral instability following total knee arthroplasty remains one of the major complications requiring operative intervention. In spite of recent advances in technique and instrumentation, the rate of this complication remains disturbingly high. A comprehensive analysis of cause reveals malalignment of any of the components to be potentially responsible, particularly valgus or internal rotation malalignment of either femoral or tibial component, as well as lateral displacement of the patellar component. Underresection of the patella or oversizing the femoral component may also contribute to excessive lateral retinacular tightness. When confronted with patellofemoral instability, the surgeon must first look for and correct the cause. Component malalignment requires component revision. Extensor mechanism imbalance requires either proximal or distal realignment. Lateral release alone invites recurrence of the problem.