Partial resurfacing arthroplasty of the femoral head in avascular necrosis. Methods, indications, and results.

The current study reports results using a partial surface replacement for osteonecrosis of the femoral head. The surgical technique, implant design, and instrumentation cause minor soft tissue disruption and require little bony resection. Thirty-seven prostheses were placed in 33 patients during the past 7 years. The mean age of the patients was 43 years (range, 24-59 years), and the preoperative Ficat classification was Stage III in 26 hips, Stage IV in 10, and Stage II in one hip. For the surviving prostheses, the mean followup was 49 months (range, 24-89 months). Of the 28 surviving implants, 24 continue to function well and the patients have excellent or good hip scores according to the Merle d'Aubigne system. There were nine failures, mainly attributable to the extension of the osteonecrosis. In comparison with alternative techniques, the operative surgery for partial surface replacement is straightforward, requiring little preoperative planning and immediate weightbearing postoperatively. Should failure occur, little bone stock loss is incurred and revision to a total hip replacement is as simple as primary hip arthroplasty.

[Original valgus tibial osteotomy by internal opening and without loss of bone contact. Technique and incidence of consolidation speed: a preliminary series of 33 cases]. / Ostéotomie tibiale de valgisation originale par ouverture interne sans perte de contact osseux. Technique et incidence sur la rapidité de consoliation: à propos des 33 premiers cas.

PURPOSE OF THE STUDY: We propose an original open wedge medial osteotomy of the upper tibia. This new technique, unlike conventional open wedge osteotomies, allows a large bone contact surface without requiring graft filling. MATERIAL AND METHOD: The new technique is based on two anterior and posterior hemi-osteotomies instead of the single osteotomy with the classical technique. The two hemi-osteotomies join laterally but start medially at very different heights on the tibia. The two hemi-osteotomies open a wedge but nevertheless lead to a very large bone contact due to the slippage in a frontal connecting frontal osteotomy. The technique uses a cutting guide to allow perfect orientation meeting the requirements of the operative plan. We studied prospectively the first 33 patients who underwent this new procedure in two centers (Jouvenet Clinic and Tenon Hospital, Paris). We report here the effect on healing time. RESULTS: There was one failure (retarded healing and partial loss of correction) due to incomprehension of the postoperative instructions. The other 32 cases consolidated in 45 days. No graft filling was needed.

Preliminary results of partial surface replacement of the femoral head in osteonecrosis.

We report our initial results using a partial surface replacement for osteonecrosis of the femoral head. We believe the prosthesis has the most minimalist design that has been reported either in Europe or North America. The surgical technique, implant design, and instrumentation cause minor soft tissue disruption and require little bony resection. We report the results of our first 25 prostheses performed over the past 5 years in 19 patients. The mean age was 42.5 years, (range, 24-59 years), with a preoperative Ficat classification of 15 hips, stage III; 9 hips, stage IV; and I hip, stage II. For the surviving prostheses, mean follow-up was 43 months, (range, 20-60 months). Of these 19 surviving implants, 15 continue to function well with excellent or good hip scores according to the Merle d'Aubigne system. We have had 6 failures: 1 owing to technical error, 4 owing to local tissue factors, and 1 owing to a progression of the osteonecrosis. The parameters for the use of this prosthesis are defined with our increasing experience, and the prosthesis is compared with other prosthetic implants available. In comparison with alternative techniques, the operative surgery is straightforward requiring little preoperative planning; immediate weight bearing is allowed postoperatively. Should failure occur, little bone stock loss is incurred, and revision to a total hip replacement is as simple as primary hip arthroplasty.

[External fixation in fractures of the lower limb in children]. / La fixation externe dans les fractures du membre inférieur de l'enfant.

PURPOSE OF THE STUDY: The indications, morbidity and results of the use of external fixation for fractures of the lower limbs in children is presented. MATERIAL AND METHOD: We studied 72 fractures of the lower limbs (femur: 25; tibia: 47) in 63 children over a seventeen year period. Average age at fracture was 10 yrs 6 mos. (range 4 yrs 5 mos to 14 yrs 6 mos). Forty fractures were open fractures. The indication for external fixation was decided in three different situations: 39 isolated fractures, 11 patients with multiple fractures, and 13 polytraumatized patients. Three different devices were used: Illizarov: 4, Judet: 16, Orthofix: 52. The fixators were left in place until fracture union was demonstrable. RESULTS: Final results were classed into three groups: good, good following reoperation and sequelae. Comparison of the three different series was made using Student's T test. 9 axial deviations or malrotations occurred: 6 times correction was possible with the device in place. Three cases of osteomyelitis occurred at the fracture site. 23 pin tract infections occurred (23 per cent) 5 of which were persistent and 4 required reoperation. The average healing time was different in the three groups: 4.5 mos for isolated fractures: 8.1 mos for multiple fractures and 5.7 mos for polytraumatized patients. Reoperation was required for 4 patients: 2 bone grafts, 1 decortication, 1 bone transport. Ten refractures occurred following removal of the device, 8 times in patients presenting multiple injuries. In 46 patients with a follow-up greater than 18 months, 9 presented an overgrowth between 1 and 2 cm. Following an average follow-up of 2 years 4 months, 7 patients presented sequelae, 56 had good results, 18 following reoperation. DISCUSSION: The use of external fixation remains an irreplaceable method for osteosynthesis of open fractures with severe soft tissue injuries, multiple fractures or in the polytraumatized patient. Some disadvantages such as pin tract infections and refracture following device removal should be taken into consideration before using it for the treatment of simple, isolated closed fractures of the lower limbs in children. CONCLUSION: When external fixation is chosen for treating fractures, it is preferable to use a modular device which allows axial corrections. Local pin site care is essential to prevent early infection. Early weight bearing and dynamization as soon as possible will promote callus mineralization, removal of the device must be progressive and cast protection is recommended.