Results of a hydroxyapatite-coated (Furlong) total hip replacement

Abstract

We describe the survival of 134 consecutive JRI Furlong hydroxyapatite-coated uncemented total hip replacements. The mean follow-up was for 14.2 years (13 to 15). Patients were assessed clinically, using the Merle d'Aubigné and Postel score. Radiographs were evaluated using Gruen zones for the stem and DeLee and Charnley zones for the cup. Signs of subsidence, radiolucent lines, endosteal bone formation (spot welds) and pedestal formation were used to assess fixation and stability of the stem according to Engh's criteria. Cup angle, migration and radiolucency were used to assess loosening of the cup. The criteria for failure were revision, or impending revision because of pain or loosening. Survival analysis was performed using a life table and the Kaplan-Meier curve. The mean total Merle d'Aubigné and Postel score was 7.4 pre-operatively and 15.9 at follow-up. During the study period 22 patients died and six were lost to follow-up. None of the cups was revised. One stem was revised for a periprosthetic fracture following a fall but none was revised for loosening, giving a 99% survival at 13 years. Our findings suggest that the long-term results of these hydroxyapatite-coated prostheses are more than satisfactory.

Full-field in vitro measurements and in silico predictions of strain shielding in the implanted femur after total hip arthroplasty

“…Calcar atrophy was also noted in other follow-up studies for the Furlong HAC stem, indicating resorption in Gruen zone 7. 42,43 Moreover, Singh et al 43 noted formation of new bone extending from the femoral cortex to the stem-tip, i.e. in Gruen zone 4, consistent with the slight increase in strain at GZ-4 observed in this study.…”

THA with the ABG I Prosthesis at 15 Years: Excellent Survival with Minimal Osteolysis

“…The relatively young mean age of the cohort relates to the senior author's preference to use cementless hips in young patients in an attempt to preserve bone stock for subsequent revision surgery and is comparable to the mean ages from similar studies using the ABG I prosthesis [2,8,12]. A metal-onpolyethylene bearing (sterilized through gamma irradiation [25][26][27][28][29][30][31][32][33][34][35] in air) with a stainless steel 28-mm-diameter head was used in all hips.…”

Periprosthetic Bone Remodeling after 12 Years Differs in Cemented and Uncemented Hip Arthroplasties

“…In comparison, our study showed a different pattern of bone remodeling with greater preservation of bone density in the distal medial and the distal lateral cortex with the uncemented stem. Longitudinal noncomparison studies with Charnley cemented prostheses [5] have observed that at 1 year, there was a reduction in BMD of 6.7% in the calcar region and an increase of 5.3% in the femoral shaft distal to the tip of the implant [22]. Studies with an uncemented HA-coated prosthesis [19] showed that the BMD was lower in Gruen Zones 1 and 7 and concluded prosthesis design influences periprosthetic bone loss.…”

“…With good survival of the HA-coated Furlong 1 cup and stem [22], better preservation of periprosthetic bone would potentially make revision surgery less complex and also possibly decrease the risk of periprosthetic fracture. Additional long-term studies of remodeling and periprosthetic bone density between cemented and uncemented implants can help us understand preservation and behavior of periprosthetic bone stock.…”