Abstract
This prospective study evaluates the outcome of a new metal -on-metal total hip replacement in a younger group of patients.
Fifty-five primary all-metal total hip replacements (THR) were evaluated prospectively at a follow-up of 2.8–5.5 years. Patients were selected according to age and activity levels. The mean age was 58 years (41–69). 33 males and 22 females were included in the study. Surgery was carried out for osteoarthritis in 52 patients and for non-union fractured femoral neck, ankylosing spondilitis and post slipped upper femoral epiphysis in the three remaining patients. A single surgeon (the senior author) through the posterior approach carried out the surgery. All patients received the porous coated titanium shell with a Morse taper cobalt chrome liner and double wedge tapered polished cobalt chrome stem and modular head. Blood metal ion analysis was performed on a cohort of 24 patients using High Resolution Inductively Coupled Plasma Mass Spectrometry, sampling taken preoperatively and then repeated post operatively at 6 months, 1 year and then annually.
Clinical results have been excellent. X rays show Harris A cementation in all femurs, with no component migration or radiolucencies being identified on follow-up radiographs. No prosthesis to-date has required revision. One patient has died and one is lost to follow up. The following non-device related complications were reported in the group, 2 (4%) superficial wound infections, 1 (2%) dislocation, 1 (2%) thrombosis, 1 (2%) IT band defect and 2 (4%) impingement. The dislocation was treated with a closed reduction. The impingement has resolved by one year in both patients. The results of the pre and postoperative blood metal ion analysis demonstrate some elevated levels, these levels being similar to those previously reported in the literature.
The hybrid all-metal THR may represent a valuable alternative in the younger, high demand patient.
The abstracts were prepared by Mr Richard Buxton. Correspondence should be addressed to him at Bankton Cottage, 21 Bankton Park, Kingskettle, Cupar, Fife KY15 7PY, United Kingdom
