D. Trias et al., GAIT ANALYSIS OF MYOPATHIC CHILDREN IN RELATION TO IMPAIRMENT LEVEL AND ENERGY-COST, Journal of electromyography and kinesiology, 4(2), 1994, pp. 67-81
The electromyographic and kinematic patterns of gait and its energy co
st were studied in 12 myopathic patients who were still walking and 12
normal subjects. On the basis of significant gait variables, three di
stinct levels of impairment were defined in the group of myopathic sub
jects: early, intermediate and final. These clusterings were predicted
with 95.7% accuracy by two gait variables: the stance phase duration
and the heel vertical excursion. The gait patterns of each group were
compared to the control group. Reduced speed and range of motion, shor
t stride length, small foot-floor clearance, increased energy cost and
lateral displacements of centre of gravity were typical and increased
with the muscular weakness. The activation of soleus muscle occurred
progressively earlier as did the cessation of tibialis anterior activi
ty. In severe disorders, there was increased activity in the muscles a
cting on the hip and knee. When muscular dystrophy leads to more disab
ility the myopathic patients tended to change from the normal plantigr
ade gait pattern to an infantile digitigrade-like pattern with a decre
ase of the tibialis anterior muscle work.