Normal gait, stance, and coordination require integrity of the motor, vestibular, cerebellar, and proprioceptive pathways ( see also Movement and Cerebellar Disorders Movement and Cerebellar Disorders ). A lesion in any of the pathways causes characteristic deficits:
Patients with cerebellar ataxia require a wide gait for stability.
Footdrop causes a steppage gait (lifting the leg higher than normal to avoid catching the foot on surface irregularities).
Pelvic muscle weakness causes waddling.
Spastic leg causes scissoring and circumduction.
Patients with impaired proprioception must constantly observe placement of their feet to avoid tripping or falling.
Coordination can be tested with finger-to-nose or knee-to-shin maneuvers, which help detect ataxic movements.