Introduction. Alternative bearing surfaces to polyethylene have been introduced to avoid the appearance of osteolysis in THR. The aim of this study has been to perform prospective analysis of the data from a multi-center clinical trial for assessing the incidence of early alumina-specific-complications.

Material and Methods. We analysed 310 Cerafit cups associated with a Multicone-HA stem using alumina-on-alumina bearings implanted in four institutions from 1999 to 2003, with a mean follow-up of 4.7 years. Patients’ mean age was 52.8+13.4 years. Linear femoral head penetration was analysed using a software package.

Results. There were 4 revisions: 2 revisions due to dislocations resulting poor surgical technique (1 cup and 1 stem) and 2 revisions after a trauma (1cup and 1 stem). There was 1 alumina liner fracture 36 months after implant in a hip with a horizontal acetabular angle (35°) and a thin alumina liner (size 50/32). The other cases showed good clinical and radiographic results at the end of follow-up. The radiographic difference between the femoral head and cup centres at 6 weeks postsurgery was 2.48+0.60 mm, without changes in the course of the follow-up. The mean linear femoral head penetration was unreliable (0.00186+0.0032 mm/year) because it was below the mean error for the measurement system.

Conclusions. These data demonstrate that Cerafit Alumina-on-Alumina prostheses show excellent results after 5 years. Liner fractures are uncommon. Despite the blurred alumina images, the digitized method, although not totally accurate and used only for a general estimate, allows us to measure the approximate distance between the centre of the cup and the centre of the femoral head. Changes in linear femoral head penetration were not seen in any hip. Continued follow-up should determine if reduction in wear among the alumina-on alumina bearings results in less osteolysis.

Introduction and Objectives: The increase in hip replacement surgery in recent years as a consequence of the aging population and a greater demand placed on joints by our current lifestyle has caused an increase in related complications. The rate of intraoperative periprosthetic fractures is between 0.8 and 2.3%, and postoperative fracture rates reach 0.1% in some studies. This type of fracture is usually complex, and treatment is almost always quite difficult.

Materials and Methods: This study concentrates on peri-prosthetic hip fracture as a postoperative complication examining cases treated during the last 5 years. We have included cases of cemented and cementless partial and total arthroplasty. In this study, we did not include intra-operative fractures (secondary to surgical manipulation, as a result of reaming, cementing, or impaction of prosthetic components) because an irregular clinical history was associated with such cases, only reflecting those which required some type of synthesis, particularly cer-clage. The Johanson scale and the AAOS classification were used to classify fractures.

Results: Of 30 periprosthetic fractures recorded during the study period, 11 patients (36.7%) were males and 63.3% were female. Of fractures of the femoral diaphysis, more than half were Johanson Type II. Only one case involved the acetabulum. Nearly 17% required revision of some prosthetic component, and about one-third could be resolved orthopaedically. Of cases treated surgically, most complications were related to the surgical wound.

Discussion and Conclusions: The type of treatment used depends on various factors, such as type of fracture and fracture line, patient age, prosthetic loosening, etc. Individualised treatment is therefore the standard. We have observed no abnormalities in bone healing. Although this type of fracture is fortunately rare, we consider good preoperative planning and a thorough postoperative follow-up to be very important for the correct resolution of this difficult problem.