We have investigated whether control of balance is improved during stance and gait and sit-to-stand tasks after unilateral total hip replacement undertaken for osteoarthritis of the hip.

We examined 25 patients with a mean age of 67 years (sd 6.2) before and at four and 12 months after surgery and compared the findings with those of 50 healthy age-matched control subjects. For all tasks, balance was quantified using angular measurements of movement of the trunk.

Before surgery, control of balance during gait and sit-to-stand tasks was abnormal in patients with severe osteoarthritis of the hip, while balance during stance was similar to that of the healthy control group. After total hip replacement, there was a progressive improvement at four and 12 months for most gait and sit-to-stand tasks and in the time needed to complete them. By 12 months, the values approached those of the control group. However, trunk pitch (forwards-backwards) and roll (side-to-side) velocities were less stable (greater than the control) when walking over barriers as was roll for the sit-to-stand task, indicative of a residual deficit of balance.

Our data suggest that patients with symptomatic osteoarthritis of the hip have marked deficits of balance in gait tasks, which may explain the increased risk of falling which has been reported in some epidemiological studies. However, total hip replacement may help these patients to regain almost normal control of balance for some gait tasks, as we found in this study. Despite the improvement in most components of balance, however, the deficit in the control of trunk velocity during gait suggests that a cautious follow-up is required after total hip replacement regarding the risk of a fall, especially in the elderly.

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients’ acceptance, taking into account previous computer experience, age and gender.

Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients’ preferences and minimising administrative work.