MASSIVE ALLOGRAFT RECONSTRUCTION DURING REVISION TOTAL KNEE ARTHROPLASTY: 14 PATIENTS WITH AT LEAST TWO YEARS FOLLOW-UP

Abstract

Purpose: Revision total knee arthroplasty (RTKA) is particularly difficult and results more variable than primary total knee arthroplasty due to the added problem of bone loss. Massive bone allografts have been proposed to restore bone stock and mechanical conditions as close to the physiological situation as possible. The purpose of this retrospective analysis was to assess clinical and radiological results after knee reconstruction with massive allografts in patients undergoing revision total knee arthroplasty.

Materials and method: This series included 14 patients who underwent a revision procedure between February 1990 and August 1998 for RTKA with segmentary bone loss and bone defects. This group included seven patients with mechanical failure and seven others with septic loosening. Reconstruction was achieved with a massive allograft sealed around a long stem cemented implant. The composite assembly was impacted into the patient’s bony segment. The allografts were used to reconstruct the distal femur in nine cases, the proximal tibia in one, and both in the others. The IKS score and radiographic homogenisation of the host-graft junction were assessment criteria.

Results: Mean follow-up was 50 months (24–110). Mean IKS score was significantly improved from 43 (11–70) pre-operatively to 75 (40–100) at last follow-up (Wilcoxon test, p = 0.002). At last follow-up, the flexion-extension amplitude was 91±10°. Radiographic integration of the allografts was achieved in 14 out of 18 grafts. Three allografts were resorbed leading to fracture with subsequent implant failure and a new revision in two. There were no infections.

Discussion and conclusion: Bone grafts may be a solution to the difficult problem of bone loss during RTKA. Massive grafts combined with long stem implants have given encouraging early and mid-term results. The duration of these results is under evaluation.