Abstract
Background: Revision total hip replacement is challenging when there is severe proximal bone loss. The Kent hip femoral prosthesis – a distally locked femoral stem – was designed to overcome this difficulty, however no study to date has assessed its durability. Methods: We independently reviewed the results of 105 Kent Hip Prostheses used at one hospital between 1987 and 2000. The indication for revision was aseptic loosening in 64, periprosthetic fracture in 19, septic loosening in 4, and severe bony deformity in 14. In the remaining 4 cases, a Kent hip prosthesis was inserted in the presence of metastatic tumour in the proximal femur to enable mobilisation. A functional evaluation of these patients using the Oxford Hip Score and a survival analysis of the stems was performed. Results: The mean duration of follow-up was 5.3 years (range 20 months to 15 years). The mean time to full weight bearing following surgery was 4 days and mean hospital stay was 13 days. Almost all patients experienced substantial improvement in hip related pain and disability (as measured by the Oxford Hip Score). 12 stems required further revision. Taking removal of the stem for any cause as the end point, cumulative survival at 15 years was 88%. Conclusions: Cumulative survival rates for the Kent hip femoral prosthesis compare favourably with other revision stems used where there is severe proximal bone loss. It enables early full weight bearing and hospital discharge, resulting in a low post-operative medical complication rate. However the need for continuing follow-up remains, since the rate of complications such as locking screw fracture, aseptic loosening, and periprosthetic fracture, may increase in the future.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
