Foot drop is caused by paralysis of the anterior and lateral calf muscles and spastic pulling of the posterior calf muscles, which manifests as a symptom of not being able to dorsiflex the foot, dragging the diseased foot or lifting the lower limb on the side higher when walking, and always touching the ground toe first when landing. 1, causes of foot drop formation Foot drop in stroke patients is a complication caused by damage to the central nervous system, reflex sympathetic dystrophy, and neurovascular atrophy. It is also associated with changes in modulating the postural reflexes of the ankle extensors (except in the context of muscle activity) to alter the level of gravity-support burden.Cart et al. suggested, by synthesizing a large number of relevant experimental and clinical studies, that spasticity is not only related to the loss of central control of the hypocondrium, but also to changes in the physical properties of muscle fibers and tendons, and is most likely related to braking and disuse. Braking causes changes in the passive and active properties of muscles, tendons and connective tissue, including changes in muscle fiber type, cross-bridge connective tissue, loss of muscle tubercle, loss of water, changes in collagen deposition and viscosity, resulting in muscle stiffness and increased tension, which constitute factors that increase resistance to joint movement. If the triceps calf muscle continues to spasm without stretching and causes contracture of the Achilles tendon, it will make the reversible foot drop to irreversible foot drop. In addition, due to prolonged braking, the anterior calf muscle group (anterior tibialis) and lateral muscle group (peroneus brevis) are underactivated, resulting in disuse muscle atrophy and difficulty in dorsiflexion of the foot. This imbalance of muscle strength between the dorsalis pedis/toe flexors makes the affected foot droop, inversion and heel not land normally, and the affected lower limb appears “longer” than the healthy side, while the knee extensor spasm makes the knee joint flexion insufficient, resulting in a typical compensatory “circle gait This causes a typical compensatory “circling gait”. This is detrimental to the patient’s walking, stairs and daily life. Therefore, it is of great significance to correct foot drop, break the extensor spasm pattern and make the ankle produce active ankle dorsiflexion to correct the gait and improve the walking ability. 2. Prevention of foot drop With the progress of rehabilitation medicine, rehabilitation treatment should be carried out in all aspects of medical care and the whole process from the onset of illness to the recovery period. Prevention of foot drop is very important in the care of acute stroke patients. Early care of the patient’s affected foot can prevent the occurrence of foot drop and facilitate the partial or complete recovery of the normal function of the affected foot. The care methods are: ① Placement of the ankle joint: the patient is lying flat, a small cotton circle is placed on the heel to prevent pressure sores, the ankle joint is kept in a dorsiflexion-neutral position, and a small sponge pillow or cotton pad is laid on a wooden board under both feet so that the bottom of the foot is perpendicular to the bed and the toe is centered upward. To inhibit plantar flexion and keep the ankle joint in a functional position, avoid heavy objects or quilts for compression at the same time. (2) Ankle dorsiflexion exercise: The patient is placed in the supine position, supported by a pillow under the hip joint, with the palm of the foot as vertical as possible to the lower leg. The caregiver fixes the patient’s ankle joint with one hand. With the other hand, assist the patient’s ankle joint to do dorsiflexion and valgus movement. (3) Hip extension, knee flexion, dorsiflexion and ankle movement: The patient is in supine position with the affected leg in hip extension and knee flexion hanging over the side of the bed. The therapist holds the patient’s foot in a dorsiflexion position and moves to the head side to assist the patient in hip extension and continues to flex the knee and dorsiflex the ankle. Ankle care can actively or passively move the joints and drive the muscles to prevent muscle atrophy and deformation of tendons and ligaments contractures, joint stiffness, and cause foot drop. Ankle rehabilitation care process for stroke hemiplegic patients can enhance the stimulation of joint and muscle proprioceptors, promote the recovery of motor function and muscle strength, inhibit the common movement pattern of lower limb extensor muscles and extensor muscle spasm, and improve the patient’s ability to control the lower limbs at will.