Clinical assessment of spastic lower limbs in adults requires identification of neurologic components (motor deficit, spasticity, co-contraction, sensory deficit) and non-neurological components (contracture) of the motor disorder and the intrinsic mechanism of the << spastic >> gait. In order to determine the nature of a complex motor disorder, the clinical can call on different diagnostic tools such as motor blocks or gait analysis measuring time-distance parameters, kinematic, kinetics, gait dynamic electromyography and energy expenditure for gait performance. Clinical assessment is guided by the therapeutic goal (function, gait, mobility, pain relief, nursing), both to propose treatment and objectively monitor treatment results in terms of deficit (strength, flexibility, appropriate contraction, muscle activation) and handicap (gait, transfers, activities of daily living).