The relationship between ankle spasticity and foot pressure during gait in people with chronic stroke

• Main Authors: Ya-Ru Yang, 楊雅如
• Other Authors: Yea-Ru Yang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/68288675667918470099

碩士 === 國立陽明大學 === 物理治療暨輔助科技學系 === 99 === Background and purpose: Impaired walking ability is a characteristic of patients with stroke. It leads to disability of their functional activities of daily life. Spasticity is one of the factors contributing to slower gait velocity and asymmetric gait pattern. Dynamic spasticity would reflect the effect of spasticity during gait more properly than resting spasticity. Previous study has shown that dynamic ankle plantarflexor spasticity is one of the factors affected walking performance of patients with stroke. On the other hand, foot pressure can provide objectively and properly analysis about the gait pattern and weight-bearing condition. It is helpful to realize the weight-bearing ability of lower extremity in people with stroke for further offering suggestion of treatment program planning and relative orthosis design. However, the relationship between dynamic ankle plantarflexor spasticity and foot pressure is unclear. Therefore, the purposes of this study are to investigate foot pressure of different area between legs, to explore the effect of dynamic ankle spasticity on foot pressure during stance phase of gait in patients with stroke, and to identify the relationship between dynamic ankle spasticity and foot pressure. Method: Twelve subjects with stroke were recruited. Their basic characteristics were recorded. The dynamic ankle plantarflexor spasticity was measured by using surface electromyography on affected gastrocnemius muscle and electronic goniometer on affected knee and ankle joints. The foot pressure was assessed by using bilateral Pedar mobile insoles. The dynamic ankle plantarflexor spasticity and foot pressure were measured concurrently while patients walking at a comfortable speed for ten meters without any devices and orthosis. Nine area of foot were included of medial and lateral heel, medial and lateral midfoot, first, second and lateral metatarsal head, hallus and 2nd-5th toes. Five foot pressure parameters contained mean force, contact time, peak pressure, pressure-time integral and contact time were analysis. The difference of foot pressure between legs was analyzed by pair-t test. The correlation between dynamic ankle plantarflexor spasticity and foot pressure was analyzed by Pearson correlation coefficients analysis. In all analysis the significant p value was set less than 0.05. Results: Different foot pressure was found between legs. Mean force was significant different in total foot, lateral heel and the second metatarsal area between legs (p＜0.05). Contact time was significant different in total foot, heel, midfoot and metatarsal area between legs (p＜0.05). Peak pressure was significant different in total foot, lateral heel, metatarsals and hallus area between legs (p＜0.05). Pressure-time integral was significant different in total foot, heel, medial midfoot, metatarsals and hallus area between legs (p＜0.05). Contact area was significant different in heel, lateral midfoot, lateral metatarsal and hallus area between legs (p＜0.05). Additionally, dynamic ankle plantarflexor spasticity was significant moderate and high negative correlation with mean force in total foot, lateral midfoot, and second metatarsal area of affected side, and also in total foot, lateral midfoot, second metatarsal area, lateral metatarsal area and hallus area of unaffected side. Dynamic ankle plantarflexor spasticity was significant moderate and high negative correlation with peak pressure in total foot, lateral heel, lateral midfoot, second metatarsal and lateral metatarsal of affected side, and also in total foot, lateral heel, lateral midfoot, metatarsal areas and hallus area of unaffected side. Dynamic ankle plantarflexor spasticity was significant moderate and high negative correlation with pressure-time integral in lateral midfoot, second metatarsal area of affected side, and also in lateral metatarsal area of unaffected side. Dynamic ankle plantarflexor spasticity was significant moderate and high negative correlation with contact area in total area, hallus and 2-5 toes area of unaffected side. Discussion and conclusion: Different mean force, peak pressure, pressure-time integral and contact area between legs during gait performance were found in people with chronic stroke. The changes in foot pressure parameters of people with stroke can reflect the decreased weight-bearing and weight-shift ability of affect lower extremity. The unaffected leg also changed the weight-beading condition and foot pressure for compensation. Dynamic ankle plantarflexor spasticity affects the foot pressure of bilateral legs. Increased dynamic spasticity caused decrease of mean force, peak pressure, and pressure-time integral in some areas of affected side. This means decreased weight-bearing ability and difficult weight shift of affected side. Hard to change the central of gravity between legs led to decreasing mean force, peak pressure, and pressure- time integral of unaffected side in double stance phase. Thus it changed the weight-bearing condition and pattern of unaffected side in stance phase.