Abstract
We prospectively studied 48 hips in 47 patients with a mean age of 59.6 years and reviewed the results after a mean period of follow up of 9 (range 7 – 12) years following revision arthroplasty for aseptic loosening using a primary HA-coated femoral stem. 1.8 Previous operations per patient were performed, ranging from 1 to 8, all patients had a femoral defect class 1 or 2 according to Paprosky. Clinical outcome was good with a mean postoperative HHS of 90 points. Pain was absent in 89%, a limp was present in 36% and 41% used a walking aid. There were 5 re-operations: 4 recurrent dislocations and 1 progressive PE wear necessitated cup revision. At 6 years, 39% cancellous densifications were seen, especially in non-tightly fitted prostheses, mainly in zone 2 and 6. Cortical thickening was seen in 30%, especially in tightly-fitted prostheses, mainly in zone 3 and 5. These differences in bone behaviour were significant (p‘0.001) and were not related with various clinical parameters. These phenomena started to appear from 6 months onwards with increasing frequency with longer follow up. The stem survival up till 9 years is 100%, no stem is pending revision at the latest follow up. We conclude that the primary Mallory Head HA-coated femoral prosthesis is a suitable prosthesis to use in revision procedures in younger patients with a lower class femoral defect. We also noticed that the radiological remodelling phenomena are not prosthesis related but femoral canal fit dependent.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
