The ABCs of Hypertonia Management – ITB, SDR, DBS Cerebral Palsy is a disorder of muscle tone caused by a non-progressive brain insult with onset with onset from prenatal brain development through early childhood. Affecting

Cerebral Palsy is a disorder of muscle tone caused by a non-progressive brain insult with onset with onset from prenatal brain development through early childhood. Affecting approximately 3/1000 children, it is the most common disabling motor disorder beginning in childhood. With a wide range of etiologies, there is also significant variability in the motor presentation. Spasticity and dystonia are both common, and often there are overlapping abnormalities of tone. A common pattern is spasticity of the lower extremities, hypotonia of the trunk and axial musculature, with dystonia dominating in the upper extremities. Spasticity is velocity dependent, typically unidirectional resistance to muscle stretch with associated upper motor neuron signs. It essentially involves disinhibition of GABA-ergic cells at the spinal cord. Dystonia is hypertonia with stereotyped writhing patterned movements, often involving co-contraction of agonists and antagonists that may involve overflow to remote muscle groups. Biochemically, multiple neurotransmitters are involved through the basal ganglia and associated interconnections. Treatment of spasticity is best managed by a comprehensive team approach that includes neurology, neurosurgery, orthopedics, rehabilitation specialists and support professionals. Initial tone management typically includes rehabilitation therapy, medications, neurotoxins and orthotics. Medications (many off label) may include baclofen, gabapentin, tizanidine and benzodiazepines. More severe patients may benefit from neurosurgical options focused on reducing tone at the spinal cord level. The chemistry of dystonia is more complex, thus the pharmacologic options are more varied and less consistently successful (table 1).