R. Vedantam et C. Ruddlesdin, THE FULLY HYDROXYAPATITE-COATED TOTAL HIP IMPLANT - CLINICAL AND ROENTGENOGRAPHIC RESULTS, The Journal of arthroplasty, 11(5), 1996, pp. 534-542
The clinical and roentgenographic results of 54 fully hydroxyapatite (
HA)-coated primary total hip arthroplasties in 45 patients was studied
. Both the femoral and the acetabular components had a 200-mu m coatin
g of hydroxyapatite. The mean age of the patients was 54.8 years. Twen
ty-three patients were between 45 and 60 years of age. There were 24 m
en and 21 women. Nine patients under went bilateral operations. The av
erage follow-up period was 46.9 months (range, 24-78 months). The aver
age preoperative Harris hip score was 48, and the average postoperativ
e Harris hip score was 94 at 1 year and 96 at 2 years. Revision surger
y for component loosening and infection was carried out in four (7.4%)
cases. There was aseptic loosening of the femoral component in one ca
se (1.85%) and of the acetabular component in two cases (3.7%). Roentg
enographic evaluation indicated that greater stress transfer occurs in
tile distal two thirds of the femoral stem. Proximomedial femoral nec
k resorption was noted in 23 cases (57.4%). Excellent to good clinical
outcome was obtained in 89% of patients. in the short term, the rate
of aseptic loosening of the fully HA-coated hip prosthesis in our seri
es is higher than the reported rates of aseptic loosening of proximall
y HA-coated total hip implants. Controlled clinical studies would be r
equired to evaluate the relative efficacy of the fully HA-coated and t
he proximally HA-coated hip prostheses.