Effects of long-distance walking on socket-limb interface pressure, tactile sensitivity and subjective perceptions of trans-tibial amputees.

PURPOSE: Many trans-tibial amputees could not tolerate long-distance walking. Lack of walking could explain for the increased cardiovascular diseases mortality rate. This study investigated the effects of long-distance walking (LDW) on socket-limb interface pressure, tactile sensitivity of the residual limb, and subjective feedbacks, which potentially identified the difficulties in LDW.
METHOD: Five male unilateral trans-tibial amputees walked on a level treadmill for a total of one hour at comfortable speed. Tactile sensitivity of the residual limb and socket-limb interface pressure during over-ground walking were measured before and after the treadmill walking. Modified Prosthesis Evaluation Questionnaires were also administered.
RESULTS: After the treadmill walking, the socket-limb interface pressure and the tactile sensitivity at the popliteal depression area were significantly reduced. This corresponds well with the questionnaire results showing that the level of discomfort and pain of the residual limb did not increase. The questionnaire revealed that there were significant increases in fatigue level at the sound-side plantar flexors, which could lead to impaired dynamic stability.
CONCLUSIONS: Fatigue of sound-side plantar-flexor was the main difficulty faced by the five subjects when walking long-distances. This finding might imply the importance of refining prosthetic components and rehabilitation protocols in reducing the muscle fatigue. IMPLICATIONS FOR REHABILITATION: • After long-distance walking (LDW) of the trans-tibal amputee subjects, there were significant increases in fatigue level at the plantar flexors. These might explain the reduced walking stability as perceived by the subjects. • LDW did not produce any problems in residual-limb comfort and pain feeling. These were in line with the significant reductions of socket-limb interface pressure and the tactile sensitivity at the popliteal depression after LDW. • Refinements of prosthetic components and rehabilitation protocols should be attempted to reduce the fatigue of the plantar flexors and facilitate LDW.