The management of spinal deformities in Duchenne muscular dystrophy. A new concept of spinal bracing.

A clinical study of 62 patients with Duchenne Muscular Dystrophy has suggested 2 pathways in the pathogenesis of the spinal deformities. In the first pathway, the patients develop an initial kyphosis due to the loss of paravertebral muscle thus placing the intrinsic ligamentous spine in an unstable position. The spine then develops a lateral curve accentuated by pelvic obliquity. In the final form, axial rotation of the spine and pelvis occurs to produce a severe deformity. In the second pathway the intrinsic spine assumes the more stable position of hyperextension with a level pelvis. This position remains relatively unchanged during the period of wheelchair confinement even though muscle deterioration progresses. A significant increase in the severity of the deformity occurs with age in those patients with unstable spines. None of the other factors examined affected the severity of the lateral curvature. A spinal brace has been designed to keep the spine extended and the pelvis level while the patients sits in his wheelchair. The purpose is to encourage the inexorable progression of muscular deficiencies to follow the second pathway. Various modifications of wheelchairs also may help to maintain spinal stability.