Classificação angular para protrusão acetabular utilizada no serviço de ortopedia da Faculdade de Medicina do ABC / Angular classification for protrusio acetabuli used in the orthopedic service of Faculdade de Medicina do ABC

Introdução: a protrusão acetabular foi inicialmente descrita por Otto, em 1824. A incidência é maior no sexo feminino e a bilateralidade, mais comum, é maior nas protrusões de etiologia primária. Sotelo-Garza e Charnley definiram uma classificação que considera a distância da parede medial em relação à linha de Kõhler. Objetivo: apresentar a classificação angular para protrusão acetabular e demonstrar sua aplicabilidade. Método: a classificação da Faculdade de Medicina do ABC (FMABC) foi determinada a partir da medida do ângulo P (ângulo de protrusão), formado pela intersecção de três linhas. Foram avaliadas radiografias de bacia em dois grupos de pacientes: o primeiro, com pacientes sem protrusão acetabular, em que foram definidos os valores de normalidade, e o segundo, com pacientes com protrusão acetabular. Destes, foram medidos o ângulo P e o tamanho da protrusão de acordo com Sotelo-Garza e Charnley, sendo os resultados comparados. Dezenove quadris com protrusão foram submetidos à artroplastia total e comparados os valores do ângulo P no pré e pós-operatório. Resultados: o valor médio do ângulo P, em pacientes sem protrusão acetabular, foi -1,22º. No segundo grupo, observou-se semelhança quando foram comparados os valores da classificação FMABC e os da classificação de Sotelo-Garza e Charnley. A comparação entre os valores do ângulo P pré e pós-operatórios resultou em diferença estatisticamente significante (p<0,001). A classificação angular foi dividida em leve, moderada e grave. Conclusões: o ângulo P foi sempre superior a zero nas protrusões acetabulares, os valores numéricos das duas classificações foram estatisticamente significativos, possibilitando a utilização dos mesmos valores da classificação de Sotello-Garza e Charnley para a classificação FMABC, e o uso de enxerto causou uma lateralização do componente acetabular.

Introduction: protrusio acetabuli was first described by Otto, in 1824. Its incidence is higher among women and the bilaterality, more common, is higher in primary etiology protrusions. Sotelo-Garza and Charnley set a classification that considers the distance of the medial wall on the Kõhler's line. Objective: to present the angular classification for protrusio acetabuli and to demonstrate its applicability. Method: the angular classification of Faculdade de Medicina do ABC (FMABC) was determined from the measure of the P angle (angle of protrusion), formed by the intersection of three lines. Pelvis radiographs were evaluated in two groups of patients: the first, with patients without protrusio acetabuli, in which the values of normality were defined, and the second, with patients who presented the disease. We measured, in the second group, the P angle and size of the protrusion according to Sotelo-Garza and Charnley, and the results were compared. Nineteen hips with protrusion were submitted to total hip arthroplasty and the values of the P angle compared in the pre and postoperative. Results: the average value of the P angle, in patients without protrusio acetabuli, was -1.22º. In the second group, a similarity was observed when we compared the values of the FMABC angular classification and the Sotelo-Garza and Charnley classification. The comparison between the values of the pre and postoperative P angle resulted in significant statistical difference (p < 0.001). The angular classification was divided into mild, moderate and severe. Conclusions: the P angle was always greater than zero in protrusio acetabuli, the values of both classifications were statistically significant, allowing the use of the Sotello-Garza and Chanrley classification values for the FMABC classification, and the use of graft lead to a lateralization of the acetabular component.

Management of different forms of varus deformity during total knee arthroplasty

Varus deformity of the lower limb is a common association of knee arthritis. The deformity-and more precisely its apex-is usually situated at the level of the joint and results from wear of the articular cartilage and subchondral bone underneath. Less commonly this deformity-due to non-united fracture, or malperformed osteotomy-maybe situated away from the joint line along the axes of the tibia or the femur. Two types of varus knee deformity in knee arthritis are therefore distinguishable, the intraarticular and the extra-articular types. Each of these types requires and deserves special attention and different way of correction during replacement of the knee joint. In this article three groups of varus osteoarthritic knees are presented, evaluated and compared. The first group comprised 82 knees with intraarticular deformity that ranged from 17 to 32 degrees and treated with total replacement of the joint after adequate soft tissue release. In the second and third groups 22 osteoarthritic knees with extraarticular varus deformity that ranged from 18 to 35 degrees were presented and differentiated according to the mode of surgical correction of the varus deformity. In one group compensatory bone cuts were carried out ignoring and compensating for the extraarticular deformity and correcting at the same time the overall limb alignment and the inclination of the joint line. In the other group, a single stage procedure that included a separate osteotomy away from the joint level corrected the deformity prior to replacement of the knee. Comparison of the three groups in this study demonstrated that total knee arthroplasty in knees with intra-articular varus deformities was relatively a simpler procedure and had superior results to the arthroplasty of the knees with extraarticular varus deformity. This procedure however, necessitated special attention to soft tissue balancing and special care in the repair of the released tissue. In the groups with extraarticular deformity limb alignment was a major concern. The worst results however, were obtained when compensatory bone resection was the technique of correction of the extraarticular varus and this was mainly due to ligament laxity. In this group tibial compensatory resection had better results than femoral compensatory resection. It is therefore concluded that during total knee arthroplasty extraarticular varus deformity is best managed independently through a separate osteotomy situated at the apex of the deformity. Careful soft tissue release and adequate repair of the released tissues were necessary for the stability after total knee arthroplasty in knees with intraarticular varus deformity