Aim We set out to see

whether ankle replacements were capable of maintaining a normal gait and

Method We performed gait analysis on 15 patients, with 13 ankle replacements (mixture of Buechel Pappas and Scandinavian Total Ankle Replacement [STAR]) and three ankle arthrodeses. One patient had an ankle replacement on one side and an arthrodesis on the other. We used a standard seven camera infrared system and force plate at a frequency of 240Hz.

There were a mixture of patients with osteoarthritis and rheumatoid arthritis. We also looked at the ‘normal’ side of the patients with unilateral surgery.

Results We found that patients with ankle replacements had near normal gait parameters for both kinetic and kinematic data whereas patients with ankle fusions had significantly altered kinetic and kinematic data. This was both in respect to normal individuals and to the unoperated side. Patients with rheumatoid arthritis had some alteration in the gait pattern on the normal side – the presence of an ankle replacement on the other side maintained this pattern on the operated side, suggesting that this was not due to abnormalities within the ankle but in the rest of the foot and lower limb. Patients with unilateral osteoarthritis for which they had an ankle replacement had essentially normal kinetics and kinematics of both ankles.

Conclusion We have been able to show that an ankle replacement performs well in terms of restoring/maintaining a normal gait pattern, whereas ankle arthrodesis, although gives a functional and pain free foot, significantly alters the normal gait pattern.