We compared thromboembolic events, major haemorrhage
and death after total hip replacement in patients receiving either
aspirin or low-molecular-weight heparin (LMWH). We analysed data from
the National Joint Registry for England and Wales linked to an administrative
database of hospital admissions in the English National Health Service.
A total of 108 584 patients operated on between April 2003 and September 2008
were included and followed up for 90 days. Multivariable risk modelling
and propensity score matching were used to estimate odds ratios
(OR) adjusted for baseline risk factors. An OR <
1 indicates
that rates are lower with LMWH than with aspirin. In all, 21.1%
of patients were prescribed aspirin and 78.9% LMWH. Without adjustment, we
found no statistically significant differences. The rate of pulmonary
embolism was 0.68% in both groups and 90-day mortality was 0.65%
with aspirin and 0.61% with LMWH (OR 0.93; 95% CI 0.77 to 1.11).
With risk adjustment, the difference in mortality increased (OR
0.84; 95% CI 0.69 to 1.01). With propensity score matching the mortality difference
increased even further to 0.65% with aspirin and 0.51% with LMWH
(OR 0.77; 95% CI 0.61 to 0.98). These results should be considered
when the conflicting recommendations of existing guidelines for
thromboprophylaxis after hip replacement are being addressed.
Peri-prosthetic fracture after joint replacement in the lower limb is associated with significant morbidity. The primary aim of this study was to investigate the incidence of peri-prosthetic fracture after total hip replacement (THR) and total knee replacement (TKR) over a ten-year period using a population-based linked dataset. Between 1 April 1997 and 31 March 2008, 52 136 primary THRs, 8726 revision THRs, 44 511 primary TKRs, and 3222 revision TKRs were performed. Five years post-operatively, the rate of fracture was 0.9% after primary THR, 4.2% after revision THR, 0.6% after primary TKR and 1.7% after revision TKR. Comparison of survival analysis for all primary and revision arthroplasties showed peri-prosthetic fractures were more likely in females, patients aged >
70 and after revision arthroplasty. Female patients aged >
70 should be warned of a significantly increased risk of peri-prosthetic fracture after hip or knee replacement. The use of adjuvant medical treatment to reduce the effect of peri-prosthetic osteoporosis may be a direction of research for these patients.
Antibiotic prophylaxis is routinely administered during joint replacement surgery and may predispose patients to