ALS pearls-- ALS mimics

spondylitic myelopathy -- limb fibs should go away within six months of fixing spine

inclusion body myositis pearl check finger flexors esp FPL FDP, forearm atrophy and check for absent fascics and symmetry

spinal cord AVM

heavy metal intoxication -- lead-- check for basophilic stippling and consider treatment with dmpa

lymphoproliferative disorder

multifocal motor neuropathy with conduction block (anti GM1 seen in about half) rsponds to IVIG

vasculitis

motor polyradiculopathy

infectious (polio, WNV)-- EMG shows poor recruitment, then fibs in 4-6 weeks

Bulbospinal mononeuropathy (Kennedy's syndrome) X linked, presents in men with symmetrical weakness, atrophy and fasciculations of bulbar and proximal limb muscles, testicular atrophy and gynecomastia.Occurs early, diagnosed by a CAG repeat, and is associated with a normal lifespan. Consider in males with slow course. Fascics are more pronounced in this disorder, but its all LMN.

Spinal muscular atrophy (Werdnig Hoffman, Kugelberg Welander)-- kids, young and old adults

Progressive lateral sclerosis (UMN variety) is associated with a normal lifespan

Benign fasciculations

cramp fasciculation syndrome-- easily treated with membrane stabilizers

Monomelic atrophy-- focal variant

frontotemporal dementia- identical path finding seen by Neumann ALS spectrun disorder?

Machado Jospeh disease= spinocerebellar atrophy tpe 3. See prominent anterior horn disorder plus ataxia and myelopathy

polyglucosan body disease-- rare UMN and LMN findings plus sensory changes and shite matter changes on MRI, with rare glucosan bodies seen on sural nerve biopsy.

Acid maltase deficiency may mimic PM abnormal respiratory muscles.

Syrinx

true neurologic TOS thoracic outlet syndrome -- shows decreased median CMAP, normal median SNAP, decreased ulnar SNAP, decreased medial antebrachial SNAP; needle shows median > ulnar hand involvement; lower trunk median/radial innervated forearm muscles (FPL, EIP)

myofibrillar myopathy-- = Desmond's myopathy-- mimics IBM. Get quad atrophy, medial gastroc, dysphagia, atrophy of VM/VL but rectus femoris is spared and is normal