Acetabular allograft reconstruction in total hip arthroplasty: preliminary report with clinical, roentgenographic and scintigraphic analyses.

From January 1986 to June 1991, we used structural allografts to augment major acetabular deficiencies during primary or revision total hip arthroplasty (THA) in 54 patients. Forty-four patients (46 hips) with a minimal follow-up of two years were reviewed. The average patient age was 50.2 years. The diagnosis was loose THA component in 36 hips, six failed Austin-Moores, three septic hip sequelae, and one failed bipolar hemiarthroplasty. Their preoperative hip ratings (modified d'Aubigne and Postel rating system) averaged 10.7 points. Forty-five allografts (98%) united roentgenographically with an average union period of 11.8 months. Five acetabular components (10.9%) developed aseptic loosening; one of them underwent revision using a healing allograft and one hip needed further acetabular reconstruction with allograft due to complete necrosis of the original allograft. One additional hip required resection arthroplasty for septic loosening. The 43 surviving hips had a mean hip score of 16.7 points at the latest follow-up. Radiographic evidence of graft resorption was seen in eight hips, which was not correlated with acetabular loosening. Serial single photon emission computed tomography (SPECT) study was employed postoperatively in 20 patients (21 hips) to assess the healing process and graft viability. Seven allografts (33.3%) were nonviable on serial SPECT studies, while 14 allografts (66.7%) were viable. The compatibility of host-donor A, B, O blood typing and the use of cement did not correlate with allograft viability. Allograft viability did not contribute to the failure of cup components. Considering the major acetabular deficiency and the absence of sufficient autograft material, the use of frozen allografts appears to be justified.(ABSTRACT TRUNCATED AT 250 WORDS)