Hereditary spastic paraparesis is a group of rare hereditary disorders characterized by progressive, spinal, nonsegmental, spastic leg paresis, sometimes with intellectual disability, seizures, and other extraspinal deficits.
The genetic basis of hereditary spastic paraparesis varies and, for many forms, is unknown. In all forms, the descending corticospinal tracts and, to a lesser extent, the dorsal columns and spinocerebellar tracts degenerate, sometimes with loss of anterior horn cells. Onset can be at any age, from the first year of life to old age, depending on the specific genetic form.
Symptoms and Signs
Symptoms and signs include spastic leg paresis, with progressive gait difficulty, hyperreflexia, clonus, and extensor plantar responses. Sensation and sphincter function are usually spared. The arms may also be affected. Deficits are not localized to a spinal cord segment. In some forms, patients also have extraspinal neurologic deficits (eg, spinocerebellar and ocular symptoms, extrapyramidal symptoms, optic atrophy, retinal degeneration, intellectual disability, dementia, polyneuropathy).
Hereditary spastic paraparesis is suggested by a family history and any signs of spastic paraparesis. Diagnosis is by exclusion of other causes and sometimes by genetic testing.
Treatment for all forms is symptomatic. Baclofen 10 mg po bid, increased as needed up to 40 mg po bid, is given for spasticity. Alternatives include diazepam, clonazepam, dantrolene, botulinum toxin (botulinum toxin type A or botulinum toxin type B), and tizanidine.
Last full review/revision November 2012 by Michael Rubin, MDCM
Content last modified December 2012