[Large diameter femoral heads in primary alumina/alumina and XSPE/alumina total hip arthroplasty. A follow-up study of 50 hips after average 40 months and review of literature].

Introduction: The aim of the study was a preliminary report of the use of large diameter alumina femoral heads in total hip arthroplasty.

Material and methods: In the years 2005-2008 50 THRs were implanted in 48 patients with the use of 36 mm alumina femoral heads. 5 women and 43 men in the age from 35 to 75 years (average 61 years) were operated on. Primary osteoarthritis was the cause of 41 arthroplasties, and AVN of femoral head of 9 surgeries. 18 alumina/alumina and 32 polyethylene/alumina THRs were implanted. The prospective study consisted of clinical examination with Harris Hip Score and X-ray evaluation. AP and lateral view X-rays were evaluated. The incidence of radiolucent lines around acetabular cups were noted with DeLee and Charnley zones and around stems with Gruen's zones.

Results: The follow up is from 24 to 58 months (average 40 months). There was an increase in Harris Hip Score from average 37 points (from 25 to 49 points) before operation to average 94 points (from 90 to 100 points) after the surgery. The incidence of postoperative dislocation have not been noted. Long-term postoperative X-ray examination have showed proper geometry of endoprostheses without radiolucent lines. Neither visible wear of bearing surfaces nor breakage of alumina components have been noted.

Conclusions: 1) The use of 36 mm femoral heads in total hip arthroplasty decrease the risk of postoperative dislocation. 2) Innovative biomaterials: alumina ceramics and cross-linked polyethylene give chance for decrease the incidence of osteolysis.