Walking on uneven terrain in healthy adults and the implications for people after stroke.

BACKGROUND: One third of individuals after stroke report an inability to walk in the community. Community mobility requires walking adaptability - the ability to adjust one's stepping pattern to meet environmental demands and task goals. Walking on uneven terrain (e.g. grass, gravel) has unique requirements and is a critical component of walking adaptability that has not been investigated in the post-stroke population.

OBJECTIVE: To summarize current knowledge of biomechanical and neuromuscular modifications during uneven terrain negotiation in healthy individuals and discuss implications of post-stroke impairments.

METHODS: Review of eleven studies, identified through a search of relevant literature on PubMed and CINAHL.

RESULTS: On uneven terrain, healthy adults demonstrate numerous gait modifications including a lowered center of mass, increased muscle co-contraction during stance and exaggerated or increased toe clearance during swing. After stroke, changes in muscle activity and limb coordination will likely result in difficulty or inability performing these modifications that healthy adults use to maintain stability and safety when walking on uneven terrain.

CONCLUSIONS: Studies of biomechanical and neuromuscular control of walking on uneven terrain are needed to quantify mobility limitations in adults post-stroke. Such investigations will contribute to the understanding of mobility impairments after stroke and the design of critically important intervention strategies.