Gait Testing with Recording of Head Movements and of Soleus Muscle Activity in Normal Subjects and in Patients with Equilibrium Disturbances

To clarify the peculiarities of gait disturbances in patients with labyrinthine, cerebellar and spinal disturbances, head movements and activity of the soleus muscles were studied during walking. The upward-downward (U-D), right-left (R-L) and forward-backward (F-B) movements of the head and activities of both soleus muscles were recorded by a polygraph with the aid of a five-channel telemeter. Head movements were recorded with three accelerometers attached to a helmet that the subject wore. Muscle activities was recorded by EMG with surface electrodes. At the same time the subject's foot-floor contact sequence was measured with electric switches in the shoes. These gait data were recorded on a pen oscillograph. 1) In normal subjects, head movement recording revealed regular U-D movement and F-B inclination twice in each walking cycle and regular R-L inclination once in each walking cycle. Each soleus muscle was activated at the stance phase once in each walking cycle. 2) A patient with unilateral labyrinthine disorder had head movements with irregular rhythm and ampulitude. L-R inclination of the head was not related to foot contact. The soleus muscle activities increased in the swing phase and decreased in the stance phase. 3) A patient with bilateral loss of labyrinthine excitability had small, indistinct head movements with no relation to foot contact or foot raising. The record of the soleus muscle activities indicated plolongation of the active time and overlap of the activities of the two sides. 4) A patient with spino-cerebellar degeneration had very irregular, unequal head movements, especially excessive F-B head movement. The active time of the soleus muscles was prolonged. 5) A patient with left hemiparesis due to cervical myelopathy had small, irregular U-D and F-B head movements and large, sine wave like sway in R-Lhead movements. The soleus muscle activity of the left side in the stance phase was less than that of the right side. The record of the electric foot switch indicated that the subject often missed foot raising of her left leg.