An evaluation of the Amputee Mobility Aid (AMA) early walking aid

The most popular early walking aid (EWA) in the United Kingdom (UK) is the Pneumatic PostAmputation Mobility aid or PPAM aid. A disadvantage of this device is that it does not allow a transtibial amputee to flex or extend the knee during walking. The Amputee Mobility Aid (AMA) was developed to allow knee movement, enabling transtibial amputees to practise a more natural gait. The benefits of using EWAs include early walking, reduction in postoperative oedema and improvement in patient morale. This pilot study investigated the pneumatic bag/stump interface pressures of the PPAM aid and the AMA. In addition, the range of motion of the knee on the amputated side and the mechanical knee of the AMA were compared. The AMA was found to have higher interface pressures than the PPAM aid during standing and similar pressures during supported walking. Subjects using the AMA did flex and extend their knee during walking but through a reduced range of motion. There were no significant differences between the angular movements of the AMA's mechanical knee and the patient's knee within it.