Toe walking: Muscular demands at the ankle and knee

Abstract

Perry J, Burnfield JM, Gronley JK, Mulroy SJ. Toe walking: muscular demands at the ankle and knee. Arch Phys Med Rehabil 2003;84:7-16. Objective: To compare the relationship between electromyographic activity and internal moment in heel-toe and toe walking. Design: Simultaneous recording of stride characteristics and kinematic, kinetic, and intramuscular electromyographic data; paired t tests identified significant between-condition differences. Setting: Gait laboratory. Participants: Ten able-bodied subjects. Interventions: Not applicable. Main Outcome Measures: Kinematic, moment, power, and electromyographic variables (ankle, knee). Results: Compared with heel-toe walking, toe walking showed greater plantarflexion during stance ( P[lt ].001), higher plantarflexor moments (peak, mean) during loading response ( P[lt ].001) and midstance ( P[lt ].001), lower mean plantarflexor moments during terminal stance ( P=.002), premature soleus ( P=.001) and gastrocnemius ( P[lt ].001) activity, and higher levels of mean soleus and gastrocnemius activity during stance. During toe walking, the peak internal knee extensor moment was lower in midstance ( P=.002), and power absorption was reduced in loading response; however, vastus intermedius electromyographic activity was not reduced. Conclusions: During toe walking, terminal stance soleus and gastrocnemius activity was greater, despite a lower mean internal plantarflexor moment. The dichotomy between internal moments and muscle effort (ie, electromyographic activity) was consistent with the reduction in force-generation capacity of the calf muscles when the ankle was in a plantarflexed position. [copy ] 2003 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation