Cortical Strut Allograft in Revision Total Hip Arthroplasty

Fifty-two patients with significant uncontained but non-circumferential femoral bone loss were reconstructed using cortical strut allografts. The allografts used were deep frozen and irradiated with 2.5 Mrads. The mean age was 65. The average follow-up was 4.8 (1.6–10.0) years. The following radiographic parameters were studied: location and the dimension of the allografts, resorption and incorporation of the allografts, and union between the cortical strut allografts and host bone.

Union between the allografts and host bone took an average of 10 months. There were 2 non-unions (union rate 96%) but no graft fractures. Severe graft resorption occurred in two cases. The overall radiographical failure rate was 8% (4/52). The process of incorporation could take over two years to complete.

The average length of the strut allografts immediately post-operatively was 154 mm (66–280 mm). The length of the strut allografts at final follow-up was 143 mm (54–258 mm). The percentage decrease in the length of the struts was 8% (0–48%).

The mean pre-operative and post-operative Harris hip score was 39.4 and 65.6 respectively. Six of the fifty-two patients had further femoral revision surgery (12%). None of these re-revisions was done for reasons directly related to the cortical struts.

Cortical strut allografts are useful to augment uncontained, non-circumferential femoral defects. They can remodel with time to enhance femoral bone stock. They unite consistently to host bone without significant resorption.