Following fixation of proximal femoral fractures in the elderly the operating surgeon may request that the patient be mobilised partially weight bearing on the injured limb. This instruction is most likely if the bone quality is very poor or the fracture pattern unstable, despite evidence that full weight bearing does not affect outcome.

98 elderly patients with proximal femoral fractures treated by either hip screw device, cannulated screws or hemiarthroplasty, who were previously independently mobile, have been followed prospectively to determine their ability to comply with partial weight bearing instructions.

A specially designed capacitance foot pressure device was used to determine percentage body weight transferred through the injured limb on mobilising under physiotherapy instruction over 5 days, and factors thought to be predictive of success in partially weight bearing were measured using simple ward tests.

14 patients failed to mobilise independently prior to discharge from hospital and were excluded from further analysis. Of the remaining 84 patients only 24 (28%) successfully managed to partially weight bear 30-50% of their body weight on the injured limb. Only six of those who were unable to partially weight bear on starting to walk after surgery had learnt to do so by the fifth day. Factors indicating success or failure were mental test score, grip strength and straight leg raise on the unaffected side.

This study has shown that the majority of elderly hip fracture patients are unable to partially weight bear but, if required, success can be predicted by a few simple ward tests.

It is hoped that this information will lead to the more appropriate use of inpatient physiotherapy resources.