(See also Overview of Spinal Cord Disorders Overview of Spinal Cord Disorders Spinal cord disorders can cause permanent severe neurologic disability. For some patients, such disability can be avoided or minimized if evaluation and treatment are rapid. The spinal cord... read more .)
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. Hereditary spastic paraparesis affects both sexes.
Symptoms and Signs of Hereditary Spastic Paraparesis
Symptoms and signs of hereditary spastic paraparesis 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).
Diagnosis of Hereditary Spastic Paraparesis
Clinical evaluation
Sometimes genetic testing
Hereditary spastic paraparesis is suggested by a family history and any signs of spastic paraparesis.
Diagnosis of hereditary spastic paraparesis is by exclusion of other causes and sometimes (eg, if the cause is unclear) by genetic testing.
Treatment of Hereditary Spastic Paraparesis
Symptomatic, including drugs to relieve spasticity
Treatment for all forms of hereditary spastic paraparesis is symptomatic. Baclofen 10 mg orally twice a day, increased as needed up to 40 mg orally twice a day, is given for spasticity. Alternatives include diazepam, clonazepam, dantrolene, botulinum toxin (botulinum toxin type A or botulinum toxin type B), and tizanidine.
Physical therapy and exercise can help maintain mobility and muscle strength, improve range of motion and endurance, reduce fatigue, and prevent spasms. Some patients benefit from using splints, a cane, or crutches.
Key Points
In all forms of hereditary spastic paraparesis, the descending corticospinal tracts and, to a lesser extent, the dorsal columns and spinocerebellar tracts degenerate.
Patients have spastic leg paresis, with progressive gait difficulty, hyperreflexia, clonus, and extensor plantar responses; some forms cause extraspinal neurologic deficits.
Suspect hereditary spastic paraparesis in patients with a family history and signs of spastic paraparesis; exclude other causes and if the diagnosis is unclear, do genetic testing if possible.
Treat symptoms (eg, baclofen for spasticity, physical therapy).
