Abstract
1133 patients with an intracapsular fracture of femoral neck treated by internal fixation were prospectively studied. All surviving patients were followed up for a minimum of one year from injury. The overall incidence of non-union was 229 (20.2%) and the incidence of avascular necrosis was 61 (5.4%). Fracture non-union was less common for undisplaced fracture in comparison to displaced fractures (48 out of 565 (8.5%) versus 181 out of 568 (31.9%)) and in males than females (45 out of 271 (16.6%) versus 184 out of 862 (21.3%)). The incidence of non-union progressively increased with age from one out of 17 (5.9%) in those aged below 40 years to 84 out of 337 (24.9%) in those in their seventies. For those in their eighties the incidence of non-union began to fall, but if those patients who died within one year from injury were excluded, then the incidence was found to continue to increase. For avascular necrosis there was a falling incidence with age from 9 out of 68 (13.2%) in those aged less than 50 years to 10 out of 388 (2.6%) in those aged over 80 years.
The information from this large series of patients treated by contemporary methods enables the surgeon to use the three factors of age, sex and presence of fracture displacement to predict the risk of non-union or avascular necrosis occurring.
