Incidence of five common fracture types in an institutional epileptic population.

We have reviewed 4521 patient-years and analysed 185,066 seizures to calculate the incidence of five common fractures in an epileptic population. Only 25.0 per cent of these fractures were known to have occurred during a seizure. When age and sex matched against a 'normal population', there was an increased incidence of femoral neck fractures (5.2 x), inter-trochanteric fractures (9.9 x), ankle fractures (9.9 x) and proximal humerus fractures (4.2 x). Surprisingly, there was no increased incidence of wrist fractures. Overall, there was a 4.3 x increased risk for all fractures and 3.2 x increased risk of fractures not related to fits. There was no evidence for the first fracture occurring at a younger age in this population. The possible causes of this greatly increased risk are discussed.