Uncemented primary press-fit total hip arthroplasty: a 3 to 6 years of experience.

PURPOSE: To analyse the 3 to 6 years' clinicoradiological outcome of 45 uncemented total hip arthroplasties performed in 37 patients using cementless Spotorno stem and St Nabor cup. METHODS: The main indications for surgery were avascular necrosis of the femoral head and rheumatoid arthritis. Younger patients with good bone quality and a trumpet-shaped femur were eligible. A single surgeon performed all the operations using a posterolateral approach. Patients were reviewed at 6 weeks, 3 months, 6 months, and yearly thereafter. The clinical status was recorded using the Harris Hip Score. All radiographs were analysed by 2 independent blinded observers on 2 separate occasions. RESULTS: The mean follow-up period was 49 months and the mean Harris Hip Score at the latest follow-up was 94. Osseointegration in the form of trabeculae running from the endosteum to the prosthesis surface along with tropism of the calcar was evident in 73% of the hips. None of the remaining hips showed any continuous radio-opaque lines suggestive of a lack of bone ongrowth. Patients with endosteal condensation had better Harris Hip Scores. Intra-operative stability of the implants could fairly predict outcome. CONCLUSION: Initial clinicoradiological results of uncemented total hip arthroplasty are promising in younger patients with good bone quality and a trumpet-shaped femur.