Interlimb coordination during the stance phase of gait in subjects with stroke.

OBJECTIVE To analyze the relation between contralesional and ipsilesional limbs in subjects with stroke during step-to-step transition of walking. DESIGN Observational, transversal, analytical study with a convenience sample. SETTING Physical medicine and rehabilitation clinic. PARTICIPANTS Subjects (n=16) with poststroke hemiparesis with the ability to walk independently and healthy controls (n=22). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Bilateral lower limbs electromyographic activity of the soleus (SOL), gastrocnemius medialis, tibialis anterior, biceps femoris, rectus femoris, and vastus medialis (VM) muscles and the ground reaction force were analyzed during double-support and terminal stance phases of gait. RESULTS The propulsive impulse of the contralesional trailing limb was negatively correlated with the braking impulse of the leading limb during double support (r=-.639, P=.01). A moderate functional relation was observed between thigh muscles (r=-.529, P=.035), and a strong and moderate dysfunctional relation was found between the plantar flexors of the ipsilesional limb and the vastus medialis of the contralesional limb, respectively (SOL-VM, r=-.80, P<.001; gastrocnemius medialis-VM, r=-.655, P=.002). Also, a functional moderate negative correlation was found between the SOL and rectus femoris muscles of the ipsilesional limb during terminal stance and between the SOL (r=-.506, P=.046) and VM (r=-.518, P=.04) muscles of the contralesional limb during loading response, respectively. The trailing limb relative impulse contribution of the contralesional limb was lower than the ipsilesional limb of subjects with stroke (P=.02) and lower than the relative impulse contribution of the healthy limb (P=.008) during double support. CONCLUSIONS The findings obtained suggest that the lower performance of the contralesional limb in forward propulsion during gait is related not only to contralateral supraspinal damage but also to a dysfunctional influence of the ipsilesional limb.