Source:http://linkedlifedata.com/resource/umls/id/C0037763
MSH: An involuntary contraction of a muscle or group of muscles. Spasms may involve SKELETAL MUSCLE or SMOOTH MUSCLE.,CSP: a sudden, violent, involuntary contraction of a muscle or a group of muscles, attended by pain and interference with function, producing involuntary movement and distortion.,NCI: A sudden, violent, involuntary contraction of a muscle or group of muscles.,NCI: A sudden, violent, involuntary contraction of a muscle or group of muscles.,NCI: A sudden contraction of a muscle or group of muscles, such as a cramp.