We aimed to determine the effect of surgical approach on the
histology of the femoral head following resurfacing of the hip. We performed a histological assessment of the bone under the
femoral component taken from retrieval specimens of patients having
revision surgery following resurfacing of the hip. We compared the
number of empty lacunae in specimens from patients who had originally
had a posterior surgical approach with the number in patients having alternative
surgical approaches.Objectives
Methods
Metal-on-metal hip resurfacing (MOMHR) is available as an alternative
option for younger, more active patients. There are failure modes
that are unique to MOMHR, which include loosening of the femoral
head and fractures of the femoral neck. Previous studies have speculated
that changes in the vascularity of the femoral head may contribute
to these failure modes. This study compares the survivorship between
the standard posterior approach (SPA) and modified posterior approach
(MPA) in MOMHR. A retrospective clinical outcomes study was performed examining
351 hips (279 male, 72 female) replaced with Birmingham Hip Resurfacing
(BHR, Smith and Nephew, Memphis, Tennessee) in 313 patients with
a pre-operative diagnosis of osteoarthritis. The mean follow-up
period for the SPA group was 2.8 years (0.1 to 6.1) and for the
MPA, 2.2 years (0.03 to 5.2); this difference in follow-up period
was statistically significant (p <
0.01). Survival analysis was
completed using the Kaplan–Meier method. Objectives
Methods
This study compared the primary stability of two commercially
available acetabular components from the same manufacturer, which
differ only in geometry; a hemispherical and a peripherally enhanced
design (peripheral self-locking (PSL)). The objective was to determine
whether altered geometry resulted in better primary stability. Acetabular components were seated with 0.8 mm to 2 mm interference
fits in reamed polyethylene bone substrate of two different densities
(0.22 g/cm3 and 0.45 g/cm3). The primary stability
of each component design was investigated by measuring the peak
failure load during uniaxial pull-out and tangential lever-out tests.Objective
Methods
