Spasticity is a condition of increased muscle tone in which muscles acquire a state of near constant contraction, or activity. Muscle spasticity causes a loss of range of motion of the affected area and a loss of function. There is also a resistance to movement by an examiner. In the affected muscles, spasticity can also cause symptoms such as

• pain,
• stiffness,
• tightness.

Hyperactive reflexes, sudden or involuntary movements, abnormal posture, and bone and joint deformities can result from spasticity. Spasticity occurs when there has been damage or injury to part of the spinal cord or brain. Examples of conditions that can lead to spasticity include stroke, brain or spinal cord trauma, cerebral palsy, and multiple sclerosis.

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