We prospectively studied 1023 patients who sustained an intracapsular hip fracture that was treated with internal fixation using contemporary methods. The overall incidence of avascular necrosis (AVN) was 6.6%. AVN was less common for undisplaced (4.0%) than for displaced fractures (9.5%) and in men (4.9%) than women (11.4%) who had a displaced fracture. The incidence of AVN for those aged less than 60 years and who sustained a displaced fracture was 20.6%, compared to 12.5% for those aged 60-80 years and 2.5% for those aged more than 80 years. Our study showed an increased risk of AVN with younger age and in females with a displaced fracture. We found no association between the incidence of AVN and the interval between injury to surgery.