Spastic squint is a clinically common focal dystonia disorder in which the neck muscles contract involuntarily, causing involuntary twisting of the head and neck and abnormal posture, which has a serious impact on the patient’s work, life and social life. It can occur at any age and is more common in middle-aged and elderly people, with a slightly higher incidence in women than in men. The disease starts slowly, and in the early stage it can be manifested as involuntary head and neck twisting, tilting, leaning forward or backward, and in the later stage the head and neck are often fixed in a certain abnormal posture, and the affected muscles are often accompanied by pain and stiffness, and patients often think they have cervical spondylosis and delay diagnosis and treatment. Examination may reveal hypertrophy of the spastic muscles, which may be accompanied by head tremor (head tremor), and the symptoms may be aggravated by emotional excitement, mental tension, work fatigue, etc., and may be alleviated when the head is supported and disappear during sleep. Clinically, it can often be divided into four types according to the extent of muscle involvement: 1. twisting type: the head rotates spasmodically to one side around the longitudinal axis of the body; 2. backward tilting type: the head is tilted backward paroxysmally or continuously, which can affect the patient’s walking; 3. forward flexion type: the head is bent forward with the jaw against the chest; 4. lateral tilting type: the head deviates from the longitudinal axis to the left or right, near the shoulder, often accompanied by ipsilateral shrugging. The treatment of spastic squint is based on symptom control, including oral medication, surgery and highly selective botulinum toxin injections for the neck muscles, which can be supplemented by rehabilitation and relaxation training. Commonly used oral medications include dopaminergic drugs, anticholinergic drugs, GABAergic drugs, and muscle relaxants, but the overall efficacy is poor; surgical implantation of electrodes in the deep brain can control the symptoms in some patients, but the surgery is expensive. Botulinum toxin can highly selectively inhibit the spastic contraction of the injected muscles, which can effectively control the symptoms with less pain suffered by the patients, and has become the treatment option of choice for limited dystonia.