The debate whether to use cemented or uncemented
components in primary total hip replacement (THR) has not yet been
considered with reference to the cost implications to the National
Health Service. We obtained the number of cemented and uncemented components
implanted in 2009 from the National Joint Registry for England and
Wales. The cost of each component was established. The initial financial
saving if all were cemented was then calculated. Subsequently the
five-year rates of revision for each type of component were reviewed
and the predicted number of revisions at five years for the actual
components used was compared with the predicted number of revisions
for a cemented THR. This was then multiplied by the mean cost of
revision surgery to provide an indication of the savings over the
first five years if all primary THRs were cemented. The saving at primary THR was calculated to be £10 million with
an additional saving during the first five years of between £5 million
and £8.5 million. The use of cemented components in routine primary
THR in the NHS as a whole can be justified on a financial level
but we recognise individual patient factors must be considered when deciding
which components to use.
The rate and mode of early failure in 463 Birmingham hip resurfacings in a two-centre, multisurgeon series were examined. Of the 463 patients two have died and three were lost to follow-up. The mean radiological and clinical follow-up was for 43 months (6 to 90). We have revised 13 resurfacings (2.8%) including seven for pain, three for fracture, two for dislocation and another for sepsis. Of these, nine had macroscopic and histological evidence of metallosis. The survival at five years was 95.8% (95% confidence interval (CI) 94.1 to 96.8) for revision for all causes and 96.9% (95% CI 95.5 to 98.3) for metallosis. The rate of metallosis related revision was 3.1% at five years. Risk factors for metallosis were female gender, a small femoral component, a high abduction angle and obesity. We do not advocate the use of the Birmingham Hip resurfacing procedure in patients with these risk factors.
