Cervical myelopathy caused by developmental stenosis of the spinal canal.

The authors present six patients with myelopathy caused by developmental stenosis of the cervical spine. Hyperextension injuries precipitated the onset of symptoms in two patients, aged 19 and 20 years. In four, 41 to 69 years of age, symptoms were gradual in onset, progressing to severe disability. X-ray films revealed narrowing of the dorsoventral diameter of the spinal canal to as little as 1.0 cm. The myelograms showed widening of the cord in the transverse plane strongly suggestive of an intramedullary tumor. A unique finding was maldevelopment with flattening of the neural arch often hidden by the posterior portions of the articular facets when seen in the lateral views. These patients showed no significant evidence of spondylosis, arthrosis, or any of the structural stigmata usually observed in cervical spondylotic myelopathy. When indicated, decompressive laminectomy is the treatment of choice.