Abstract
Introduction
To report the short to medium term results of acetabular reconstruction using reinforcement/reconstruction ring, morcellised femoral head allograft and cemented metal on metal cup.
Methods
Single centre retrospective study of 6 consecutive patients who underwent acetabular reconstruction for revision hip surgery.
The acetabulum was reconstructed using morcellised femoral head allograft and reinforcement or reconstruction ring fixed with screws. The Birmingham cup – designed for cementless fixation, was cemented into the ring in all cases. The uncemented Echelon stem with metal on metal modular head was used for reconstructing the femur.
Data from our previous in-vitro study had shown good pull out strength of a cemented Birmingham cup.
Results
There were 2 men and 4 women with a mean age of 75 years(57-83). Revision was performed for aseptic loosening in 2, septic loosening in 2 and peri-prosthetic fracture with loosening in 2 patients.
All patients were reviewed clinically and radiographically at a mean of 36 months follow-up(range 24 - 42 months).
Revision was not necessary in any patient for failure of acetabular or femoral fixation. However, 1 patient had revision to a proximal femoral replacement and constrained cup for recurrent infection and osteomyelitis at 24 months. This patient was excluded from the final analysis.
The mean Harris hip score at last follow up was 79(range 70-89).
Radiographic analysis revealed good graft incorporation and no signs of loosening or cup/ring migration.
No dislocations or metal ion problems were recorded in this series.
Conclusions
To the best our knowledge, this is the first series using cemented metal on metal cups within a reinforcement/reconstruction ring for revision hip arthroplasty. Excellent cemented fixation of the cup, manufactured for cementless fixation, was obtained at surgery with no evidence of loosening, and no dislocations at minimum 24 months follow up.
