RELATIONSHIP BETWEEN POLYETHYLENE WEAR, PELVIC OSTEOLYSIS, AND CLINICAL SYMPTOMATOLOGY IN PATIENTS WITH CEMENTLESS ACETABULAR COMPONENTS - A FRAMEWORK FOR DECISION-MAKING

The purpose of this study is to assess thr relationship between acetab ular component polyethylene wear, pelvic osteolysis, and clinical symp toms to determine when operative intervention should occur and to pred ict the degree of difficulty of the revision. Fifty-four revisions of failed cementless acetabular components were performed in 52 patients. All cases demonstrated polyethylene wear radiographically and in 43 c ases (80%), osteolysis of the pelvis was seen. Symptoms of groin or bu ttock pain were seen in 45 of 54 cases (83%). Preoperative staging of the disease process included one patient with wear radiographically bu t neither symptoms nor lysis (stage I), 10 patients with wear and pain (stage IIA), 8 patients with wear and lysis but no pain (stage IIB), and 35 patients with wear, lysis, and pain (stage III). Patients in st ages I and IIA could be revised with cementless components without str uctural allograft. Patients in stages IIB and III required structural allograft in 79% and cemented components in 53%. Cemented components w ere used when there was less than 50% contact between host-bone and pr osthesis. Polyethylene wear alone (stage I) is an indication of impend ing failure, and when symptoms develop (stage IIA), revision should be undertaken. The development of radiographic lysis is a critical event , and as soon as osteolysis develops (stage IIB or III), revision shou ld be undertaken immediately. From the perspective or the revision sur geon, there is great value in the early intervention for polyethylene wear and pelvic osteolysis.