With an increasing ageing population and a rise in the number of primary hip arthroplasty, peri-prosthetic fracture (PPF) reconstructive surgery is becoming more commonplace. The Swedish National Hip Registry reported that, in 2002, 5.1% of primary total hip replacements required revision due to PPF. Laboratory studies have indicated that age, bone quality and BMI all contribute to an increased risk of PPF. Osteolysis and aseptic loosening contribute to the formation of loosening zones as described by Gruen, with subsequent increased risk of fracture. The aim of the study was to identify significant risk factors for PPF in patients who have undergone primary total hip replacement (THR). Logbooks of three Consultant hip surgeons were filtered for patients who had THR-PPF fixation subsequent to trauma. Risk factors evaluated included sex, age, bone density (Singhs index), loosening zones, Vancouver classification, prosthesis stem angle relative to the axis of the femur, and length of time from THR to fracture. A control group of uncomplicated primary THR patients was also scrutinised. Forty-six PPF were identified representing 2.59% of THR workload. The male: female ratios in both groups were not significantly different (1:1.27 and 1:1.14 respectively). Average age of PPF was 72.1, which was significantly older than the control group (54.7, p>0.05). The commonest type of PPF was
