Spasticity is a condition involving an involuntary increase in muscle tone that leads to resistance against normal movements of the body and may cause pain in some individuals.
It is strongly associated with certain medical conditions of the central nervous system (CNS), such as multiple sclerosis (MS) and cerebral palsy, in addition to injury or tumor growth in the area.
Spasticity is believed to be caused by damage to the nerve pathways that are responsible for muscular movement control, although the exact mechanism of this is not known. The damage may present as a result of a variety of circumstances, including:
- Multiple sclerosis
- Cerebral palsy
- Spinal cord injury
- Trauma to the brain or head
All of these conditions have the potential to interfere with the nerve pathways involved in muscle movements and damage may, therefore, result in muscle spasticity.
The signs and symptoms of spasticity may include:
- Increased muscle tone (hypertonicity)
- Involuntary muscle spasms
- Involuntary muscle clonus
- Exaggerated tendon reflexes
- Pain or discomfort
- Muscle contracture
- Bone and joint deformities
As a result of this, many patients exhibit an altered posture or gait, known as scissoring, due to the crossing of their legs as they walk. It is also common for individuals to partake in daily activities as usual, and they may have a reduced ability to function and difficulty with personal care and hygiene. For these reasons, the quality of life can be significantly lower than the general population.
The diagnosis of spasticity should involve a thorough medical history and physical examination, with a particular focus on potential causes for the symptoms, in order to make the right diagnosis and management recommendations. Important factors to be considered include any traumatic events that may have affected the CNS, changes in medications, noxious stimuli and intracranial pressure changes.
Additionally, an electromyography can provide valuable information about the velocity of nerve conduction and magnetic resonance imaging (MRI) scans can help to visualize causative damage in the central nervous system.
The severity of the condition can be classified according to a clinical scale, such as the Ashworth Scale, Physician’s Rating Scale or the Spasm Scale.
The management of muscle spasticity typically involves a team of specialized health professions who work together to provide optimal care. This may include a neurologist, physician, physical therapist, occupational therapist, neurosurgeon and orthopedic surgeon.
Initial treatment usually consists of physical therapy with certain exercises to stretch the affected muscles. This can help to lengthen the muscle, decrease spasticity and prevent contracture. Other methods such as splinting, casting and bracing may also be used to maintain flexibility and range of motion.
Pharmacological treatment may be needed to manage symptoms of spasticity in some cases. This may include oral treatment with baclofen, clonazepam, dantrolene, diazepam, gabapentin or tizanidine. Additionally, injections of botulinum toxins or phenol can be beneficial for some patients.
Surgical procedures are also indicated in some circumstances to correct the positioning of tendons or nerve pathways. Intrathecal baclofen therapy (ITB) may be used in severe cases, which involves direct administration of baclofen to the spinal cord, thus reducing the risk of systemic side effects. Orthopedic surgery or neurosurgery can also help to remedy changes to the muscles, bones, connective tissue or nervous system.