1. Spinal muscular amyotrophy is a rare and progressive disorder that affects the motor neurons of the spinal cord.
(脊髓性肌萎缩症是一种罕见且进行性的疾病,它影响了脊髓的运动神经元。)
2. The most common form of amyotrophy is called spinal muscular atrophy (SMA).
(最常见的肌萎缩形式被称为脊髓性肌萎缩症(SMA)。)