Radiographic and histopathologic analysis of osteolysis after total shoulder arthroplasty.

HYPOTHESIS This study analyzed clinical, radiographic, and histologic data from failed total shoulder arthroplasties (TSAs) to determine factors associated with osteolysis. MATERIALS AND METHODS From 1985 to 2005, 52 patients (mean age, 61.6 years) underwent revision TSA at a single institution at a mean of 4.3 years after their index surgery. Patients were retrospectively assigned to 2 cohorts based on the presence (n = 10) or absence (n = 42) of osteolysis around their implants on the last prerevision surgery radiographs. Clinical information, associated histopathology from tissues obtained at revision surgery, and polyethylene wear data from the retrieved glenoid components were compared between groups. RESULTS In the osteolysis group, 20% had screw fixation compared with 2.5% without osteolysis (P = .039). The radiolucency score was significantly higher in the osteolysis group: 12.7 +/- 2.0 vs 8.7 +/- 3.7 (P = .003). Wear analysis of the osteolysis group demonstrated significant increases in third-body particles compared with those implants without osteolysis (P = .004). Histology available from retrieved implants demonstrated particulate debris in 62% of patients with osteolytic lesions vs 67% without osteolytic lesions (P > .05). DISCUSSION Significant differences were found in patients with osteolytic lesions compared with patients undergoing TSA revision surgery without such lesions, specifically with regard to glenoids that used adjuvant screw fixation, the presence of increased radiolucent lines, and an abundance of third-body wear. No significant differences were found in particulate wear debris despite the prevailing notion that osteolysis is associated with particulate debris from implant wear. CONCLUSION Screw fixation and third-body wear were associated with osteolysis after TSA.