Dual-mobility hips: fewer dislocations, more periprosthetic fractures

The edition in brief

In a single-centre series of uncemented total hip arthroplasty, dual-mobility bearings were associated with about three and a half times the odds of periprosthetic femoral fracture compared with ceramic-on-ceramic bearings after propensity matching (OR 3.5, 95% CI 1.3 to 8.6), while dislocation was far less common (0.4% vs 4.0%). Femoral neck fracture as the indication raised the risk of both. In 42,338 UK infants in a selective screening programme, a documented clicky hip was associated with treatment-requiring DDH (adjusted OR 4.68); 3.6% of clicky hips needed treatment, so about 26 infants would need ultrasound to find one case. A blinded randomised trial of 96 uncemented knee replacements found sequentially annealed highly crosslinked polyethylene stopped wearing after five years while conventional polyethylene kept wearing (0.46 mm by ten years), with stable component fixation in both arms. In 100 patients after quadriceps tendon ACL reconstruction, quadriceps strength symmetry at three and nine months was associated with two-year knee scores; those reaching an acceptable outcome usually had 60-70% quadriceps symmetry by three months.