label: O'Sullivan-McLeod syndrome
label_lc: o'sullivan-mcleod syndrome
description: O'Sullivan McLeod syndrome is a benign lower motor neuron disorder and a rare variant of monomelic amyotrophy (MA), characterized by an initial unilateral weakness in the intrinsic hand muscles that eventually spreads to the opposite limb (with an asymmetrical distribution) and that has a very slow progression of muscular atrophy over a 20 year period.