spasm

Spasm is a sudden, involuntary contraction of a muscle or group of muscles. It can be brief or prolonged and may be painful. Spasms are distinct from spasticity, a chronic increase in muscle tone that occurs with some neurological disorders.

Most common in skeletal muscles, muscle spasms or cramps can occur during or after exercise, at night, or with dehydration, electrolyte disturbances (low potassium, calcium, or magnesium), poor conditioning, or fatigue. Nerve or nerve root irritation, trauma, or certain medications can contribute. Spasms can also reflect conditions such as metabolic disorders, thyroid disease, kidney failure, or neurological disorders.

Common types include muscle cramps in the legs or feet; esophageal spasm, which can cause chest pain and difficulty swallowing; and vascular or cerebral vasospasm in which arteries narrow abruptly, potentially leading to chest pain or neurologic symptoms. Less common are bladder or intestinal smooth muscle spasms.

Diagnosis relies on history and physical examination. Persistent, severe, or unusual spasms may prompt blood tests (electrolytes, kidney function, thyroid); imaging or nerve studies if a nerve problem is suspected; and evaluation for underlying conditions.

Treatment focuses on relieving symptoms and treating underlying causes. Immediate relief methods include gentle stretching, massage, heat, hydration, and addressing electrolyte abnormalities. For recurrent cramps, adjusting medications, ensuring adequate mineral intake, and physical conditioning can help. In some conditions, doctors may use anticonvulsants, muscle relaxants, or vasodilators, depending on the etiology. Severe or ongoing spasms warrant medical evaluation.

Prognosis varies: isolated muscle cramps often improve with simple measures, while spasms due to chronic disorders require ongoing management. Early identification of serious underlying conditions improves outcomes.