Hereditary Spastic Paraplegia Medical Slides

Focus on the 4-5 most common subtypes covering >60% of diagnosed cases: SPG4/spastin (40% of AD-HSP, pure form, variable age of onset), SPG3A/atlastin (10% of AD-HSP, early childhood onset, pure form), SPG7/paraplegin (5-7% of AR-HSP, complex with cerebellar ataxia), SPG11/spatacsin (most common AR-HSP, complex with cognitive decline, thin corpus callosum on MRI). This practical focus avoids overwhelming learners with 80+ subtypes while covering the clinically encountered cases.

Present the mandatory workup to exclude treatable mimics: MRI brain and entire spinal cord (compressive myelopathy, MS, ALD), vitamin B12 and copper levels, VLCFA (adrenomyeloneuropathy in males), HTLV-1 serology (tropical spastic paraparesis in endemic areas), and CSF analysis (MS, neurosyphilis). Emphasize that 15-20% of patients initially diagnosed with HSP are later found to have an acquired cause, making thorough exclusion essential before committing to a genetic diagnosis.

Present the treatment ladder: (1) physical therapy and stretching (cornerstone, prevents contractures), (2) oral antispasmodics (baclofen 5-80 mg/day, tizanidine, dantrolene — efficacy limited by sedation/weakness), (3) focal botulinum toxin injections for specific muscle groups (hip adductors, ankle plantarflexors), (4) intrathecal baclofen pump for severe refractory spasticity. Emphasize the balance between reducing spasticity and preserving any functional use of spasticity for ambulation — some patients rely on extensor spasticity to stand.