We used electrogoniometers to measure the range of movement (ROM) of the knee during various activities, comparing 50 patients with osteoarthritis of the knee (OA) with 20 healthy age- and sex-matched subjects.

The minimum and maximum joint angles and the ranges of excursion of the patient and control groups were tested for significant differences, using an unrelated Student’s t-test with pooled variance. Knee flexion in patients with OA was significantly reduced during all activities (p < 0.05), but differences in knee extension were not significant except when patients negotiated stairs. We believe that this reduction in ROM is caused by inhibition due to pain when load-bearing. Static non-load-bearing measurements of the ROM poorly reflected the functional ROM, with a coefficient of determination (r²) of 0.59 in the patient group and 0.60 in the control group. Electrogoniometry of the ROM of the knee provides a reliable, accurate and objective measurement of knee function.

A series of 167 patients with Charnley-type total hip replacements were studied retrospectively to determine the incidence of trochanteric non-union, the degree of postoperative trochanteric displacement, and the relation between these two complications. The power in the hip abductor muscles, measured with a load-cell device, was significantly reduced if the trochanteric fragment had displaced proximally by more than 3 cm; 12% of those studied fell into this group and, as a consequence, had a poorer result. It was concluded that displacement of the trochanter was of greater importance than bony union in determining function in the replaced hip. Because these unwanted problems may compromise an otherwise successful operation, it is suggested tentatively that trochanteric osteotomy should be abandoned except for difficult primary operations or for revision procedures.