causes for spasticity in upper body
Spasticity is caused by an imbalance of signals from the central nervous system (brain and spinal cord) to the muscles. This imbalance is often found in people with cerebral palsy, traumatic brain injury, stroke, multiple sclerosis, and spinal cord injury.
Minor spasms may be the result of exercise or overuse of a muscle. Some spasms may be the result of a neurological condition or injury. Serious causes of spasms include kidney disease, seizure, and stroke.
Spasms and cramps can also be caused by neuromuscular disorders, such as multiple sclerosis or a spinal cord injury. Movement disorders called dystonias also lead to forceful contractions. Dystonias can be a complication of stroke. Certain medications can cause involuntary muscle contractions as well.