Reverse Microfracture of the Hip Acetabulum: A Technique for the Wave Lesion.

The long-term efficacy of the treatment of chondral lesions is very important to prevent hip osteoarthritis. Microfracture, autologous chondrocyte transplantation, and direct chondral repair, among others, are techniques that have shown good results in some cases. We propose a technique to treat wave lesions through reverse microfracture, with bubble decompression and adherence of the natural scar from the detached cartilage.

Aseptic loosening rate of the Mayo femoral stem with medium-term follow up.

The aseptic loosening rate of the Mayo hip prosthesis femoral stem was determined in a 44 patient (52 hips) series, by comparing preoperative and postoperative clinical and radiographic parameters, over a minimal 5-year postoperative period. Loosening was obvious before five years in four hips (7.6%), while the stem was considered stable in the remaining 48 hips over a mean 6.1 year period, therefore accounting for a 92.3% Kaplan-Meier survival rate. We conclude that the aseptic loosening rate is too high for the Mayo hip prosthesis femoral stem, as compared to literature data concerning the non-conservative stems.

Does trochanteric transfer eliminate the Trendelenburg sign in adults?

BACKGROUND: Premature closure of the proximal femoral growth plate results in coxa brevis, which usually is associated with insufficiency of the hip abductors. Distal and lateral transfer of the greater trochanter sometimes is recommended to correct this problem. Most of what is known arises from studies of children and adolescents. QUESTIONS/PURPOSES: We asked whether this procedure in adults with coxa brevis would eliminate hip abductor insufficiency and would improve their hip function based on the Harris hip score (HHS). PATIENTS AND METHODS: We prospectively followed 11 patients, aged 19 to 55 years (mean, 40 years) who had distal and lateral trochanteric transfer. All patients had pain and a positive Trendelenburg test before surgery. This test was performed at the latest followup by three observers and the interobserver reliability was determined by the kappa coefficient. The HHS was obtained before surgery and at the latest followup. The minimum followup was 25 months (mean, 52 months; range, 25-77 months). RESULTS: Insufficiency of the hip abductors was eliminated in seven (according to two observers) and eight (according to one observer) of the 11 patients after surgery; the kappa coefficient ranged from 0.79 to 1.0. The mean HHS improved from 64 points preoperatively to 76 points at the final followup. The two patients with preexisting severe osteoarthritis of the hip had the worst final scores and persisted with a positive Trendelenburg test at the final followup. CONCLUSIONS: Distal and lateral transfer of the greater trochanter can eliminate insufficiency of the hip abductors and improve joint function in adult patients with coxa brevis and we believe should be considered for patients without severe osteoarthritis of the hip. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Histology of the regenerate and docking site in bone transport.

INTRODUCTION: Bone transport is based on the principle of distraction osteogenesis described by Ilizarov and is a consecrated method for the treatment of segmental bone defects. One of its most problematic and, paradoxically, least studied aspects is the consolidation of the docking site. We studied histologically the ossification of the docking site and regenerate to determine any difference between them. MATERIALS AND METHODS: Nine adult sheep were submitted to correction of a 1-cm tibial diaphyseal defect using a system of plate-fixed bone transport, with latency period of 1 week and 0.2 mm distraction of the transported segment four times a day. The sheep were divided into three groups of three animals each, according to the observation period of 3, 6 or 12 weeks between the fixation of the transported fragment and the euthanasia. The docking site and the regenerate were studied histologically on sections stained with Masson trichrome. RESULTS: The main mode of docking site ossification was the endochondral one and although intramembranous ossification was also observed simultaneously, it was limited to rare and small foci. In contrast, intramembranous ossification played the major role in the regenerate, with bone formation evolving from the base segment to the target segment. CONCLUSION: The experimental bone transport model proposed in the present study permits us to conclude that there is a clear difference between the ossification of the docking site and of the regenerate.

Damage to the superior gluteal nerve after direct lateral approach to the hip.

The superior gluteal nerve may be damaged during total hip arthroplasty. We prospectively studied 40 patients who had total hip arthroplasties using the Hardinge direct lateral approach to the hip to determine any correlation between superior gluteal nerve damage and abductor function. We used the Trendelenburg test to clinically evaluate abductor function preoperatively and 1 year postoperatively. We evaluated superior gluteal nerve function by electromyography preoperatively and at 4, 8, and 12 weeks until its normalization over a maximum of 24 weeks postoperatively. The Trendelenburg test was positive in 20 patients (50%) preoperatively and in 10 patients (25%) 1 year postoperatively. Seventeen patients (42.5%) had damage to the superior gluteal nerve visible on the first electromyographic evaluation performed 4 weeks postoperatively; three (7.5%) of these patients showed changes when reevaluated 6 months postoperatively; only one of the three patients had a positive Trendelenburg test 1 year postoperatively. Nine of the 37 patients with normal electromyography results had positive Trendelenburg tests. Our results suggest there are frequent electromyographic signs of damage to the superior gluteal nerve using the direct lateral approach to the hip. However, the damage tends to improve spontaneously and does not seem to cause clinically apparent abductor insufficiency.

Tratamento das fraturas patológicas / Treatment of pathologic fractures

Säo apresentados os resultados do tratamento de 31 pacientes portadores de fraturas patológicas, operados no período de janeiro de 1986 a agosto de 1993. O tumor metastático foi a causa predominante das fraturas em questäo e, neste caso, o carcinoma de mama foi a patologia de base mais freqüente. O tratamento das fraturas patológicas dos ossos longos (23 casos) consistiu no procedimento padräo: curetagem da lesäo, fixaçäo interna com placas e parafusos e cimento ortopédico, para preencher a falha óssea e promover melhor fixaçäo. Houve cinco casos de artroplastia do quadril e três de artrodese de coluna. Houve considerável alívio da dor e melhora da qualidade de vida dos pacientes, o que justificou o tratamento empregado, apesar da curta expectativa de vida desses pacientes.

Tratamento da necrose avascular da cabeça do fêmur pela técnica de descompressäo / Treatment of avascular necrosis of the femur head by decompression technique

Os autores apresentam os resultados imediatos e tardios da descompressäo da cabeça femoral em 28 quadris (16 pacientes), sendo 12 bilaterais, em pacientes portadores de osteonecrose avascular de várias etiologias. A técnica cirúrgica foi a preconizada por Ficat e os resultados foram avaliados segundo critérios clínicos e radiológicos. Os resultados clínicos imediatos e tardios foram avaliados pelo método de Stinchefield. Os graus radiológicos pré-operatórios e pós-operatório do acometimento da cabeça femoral foram avaliados segundo a classificaçäo de Ficat. O segmento dos pacientes variou de seis semanas a quatro anos (média 20,75 ñ 18,65 meses). Apesar de näo terem ocorrido melhoras do aspecto radiológico e da mobilidade, observamos, em 100% dos pacientes, alívio da dor no pós-operatório imediato e 86% de bons resultados, no seguimento tardio, segundo os critérios de avaliaçäo utilizados

Importância dos ligamentos do compartimento lateral e dos cruzados do joelho: I. Abertura lateral / Role of the lateral compartment ligaments and of the cruciate ligaments of the knee: I. Varus opening test

Procuramos determinar a prioridade de açäo restritiva fornecida pelos ligamentos laterais e pelos ligamentos cruzados contra a abertura lateral do joelho a 0 grau e a 30 graus de flexäo. Foram utilizados 60 joelhos de cadáveres, em que fizemos seccöes ligamentares seqüuenciais envolvendo as diferentes estruturas do complexo capsuloligamentar lateral e os ligamentos cruzados. A seqüencia de secçäo variou para os diferentes grupos de joelhos. As seguintes prováveis seqüencias de açäo restritiva foram obtidas: I. Abertura lateral a zero grau de flexäo: 1. ligamento colateral lateral; 2. terço posterior capsuloligamentar; 3. terço anterior capsuloligamentar; 4. terço médio capsuloligamentar + ligamento cruzado anterior; 5. ligamento cruzado posterior. II. Abertura lateral a 30 graus de flexäo: 1. todo o complexo capsuloligamentar lateral; 2. ligamento colateral lateral + terço anterior capsuloligamentar; 3. ligamento colateral lateral + terço médio capsuloligamentar; 4. terço posterior capsuloligamentar + ligamento cruzado posterior + ligamento cruzado anterior. Relevância clínica - O conhecimento da funçäo dos ligamentos do compartimento lateral e dos ligamentos cruzados do joelho é de importância no entendimento do correto significado dos achados clínicos obtidos no exae dos joelhos traumatizados. Fudamentado na prioridade de açäo restritiva de cada estrutura, é possível reconhecer os prováveis ligamentos que se encontram rompidos, através do exame clínico cuidadoso e acurado