Spasticity is a condition in which certain muscles are continuously contracted. This contraction causes stiffness or tightness of the muscles and can interfere with normal movement, speech and gait. Spasticity is usually caused by damage to the portion of the brain or spinal cord that controls voluntary movement. The damage causes a change in the balance of signals between the nervous system and the muscles. This imbalance leads to increased activity in the muscles. Spasticity negatively affects muscles and joints of the extremities and is particularly harmful to growing children.
Spasticity may be as mild as the feeling of tightness in muscles or may be severe enough to produce painful, uncontrollable spasms of the extremities; most commonly the legs and arms. Some adverse effects of spasticity include: