Purpose: Acetabular reconstruction is particularly challenging in case of acetabular loosening with important loss of bone stock. The purpose of this retrospective study was to estimate long-term results after revision procedures using a fragmented allograft and a supporting ring.

Material and methods: From 1987 to 1995, 135 patients (135 hips) underwent this procedure. Ninety-five files were reviewed (15 patients were lost to follow-up and 25 died). The 95 patients retained for analysis were 66 women and 29 men, mean age at surgery 70 years (range 42–86). The preoperative functional score (PMA) was 8/18. The acetabular implants in situ had been cemented in 62% of the cases and non-cemented in 38%. According to the SOFCOT criteria, 79% of the loosenings were associated with grade 3 bony lesions, 15.8% with grade 4 lesions and 5.2% with grade 2 lesions. In all cases, the acetabulum was reconstructed with fragments of allografts. An Eichler ring was used in 56% of the cases, a Ganz ring in 25%, and a Muller ring in 19%.

Results: Mean follow-up was eight years (60–157 months); 39% of the patients developed early postoperative complications including one dislocation and two haematomas. Mean functional score at last follow-up was 14.8/18 with 64% good or excellent results. Reconstruction of the centre of rotation was the only factor significantly affecting results. Radiographically, 85% of the cups presented no sign of loosening at last follow-up. The grafts were considered to be assimilated or unchanged in 81% of the cases, with partial or total lysis in 19%. Actuarial analysis of cumulative survival, considering surgical revision or clinical and radiographic loosening as the endpoint was 87% at 14 years.

Discussion: Fragmented allografts can be perfectly stabilised with a supporting ring to reconstitute bony stock of the acetabulum. Long-term clinical and radiographic results are encouraging.