Femoral stems with exchangeable (modular) necks were introduced
to offer surgeons an increased choice when determining the version,
offset and length of the femoral neck during total hip arthroplasty
(THA). It was hoped that this would improve outcomes and reduce
complications, particularly dislocation. In 2010, the Australian Orthopaedic
Association National Joint Replacement Registry (AOANJRR) first
reported an increased rate of revision after primary THA using femoral
stems with an exchangeable neck. The aim of this study was to provide
a more comprehensive up-to-date analysis of primary THA using femoral
stems with exchangeable and fixed necks. The data included all primary THA procedures performed for osteoarthritis
(OA), reported to the AOANJRR between 01 September 1999 and 31 December
2014. There were 9289 femoral stems with an exchangeable neck and
253 165 femoral stems with a fixed neck. The characteristics of
the patients and prostheses including the bearing surface and stem/neck
metal combinations were examined using Cox proportional hazard ratios
(HRs) and Kaplan-Meier estimates of survivorship. Aims
Materials and Methods