Distribución de la osteólisis periprotésica en la cadera. Estudio con resonancia magnética

Abstract

Introduction Magnetic resonance imaging (MRI) is useful in assessing bone and soft tissue lesions due to the production of wear particles. Our objective was to study the distribution of lesions in patients with one type of cementless acetabular component with this technique. Material and methods We included 40 total hip arthroplasty with press-fitted hydroxyapatite porous-coated cup and multiple optional screw holes performed over a mean of 13 years. We studied the presence, extent and continuity of the granulomatous lesion and osteolysis with MRI using special pulse sequences to reduce metal artefacts. Results One hip was not amenable to analysis. An isolated granulomatous lesion was found in 3 hips, associated osteolysis in 32, in the pelvis only in 10, in the femur only in 3 and in both segments in 19. By zones, the pelvis involvement was supra-acetabular ilium in 15, ischium-pubic branch in 24, ischium in 12 and retro-acetabular ischium in 21. Only two hips and two screws central lesions were isolated from the granulomatous mass. Comments and conclusions MRI osteolysis and soft tissue lesions secondary to wear to be studied. The distribution of osteolytic areas show a peripheral pattern typical of non-perforated acetabular cups frequently coexisting with proximal femoral involvement, highlighting few isolated lesions in the holes or around the implanted screws.