A comparison of gait in spinal muscular atrophy, type II and Duchenne muscular dystrophy

Abstract

This study investigated and compared the gait of two patients with spinal muscular atrophy, type II (SMA II) and two patients with Duchenne muscular dystrophy (DMD). These diseases cause a progressive and proximal to distal muscular weakness resulting in the loss of ambulation. The DMD cases had comparable muscle weakness with the SMA II cases on manual muscle testing and patients were assessed using kinematics, kinetics, electromyography and video analysis. SMA II and DMD patients employed different gait strategies for forward movement. SMA II patients used pelvic rotation initiated by the upper body to propel the leg forward and produce the necessary step-length whereas the DMD patients tended to use hip flexion and plantar flexion. Management of SMA II patients would include preservation of hip abductor and flexor strength to maintain mobility.