If osteophytes have narrowed the spinal canal at several interspaces, a posterior decompressive laminectomy with severance of the dentate ligaments helps to prevent further injury but the procedure has been partly supplanted by anterior approaches to decompression of the spinal canal. The results of a posterior procedure in relieving symptoms are fairly satisfactory (Epstein and Epstein); in fully two-thirds of the patients, improvement in the function of the legs occurs, and in most of the others, progression of the myelopathy is halted. The operation carries some risk; rarely, an acute quadriplegia—presumably a result of manipulation of the spinal cord and damage to spinal arteries—has followed the surgical procedure. When only one or two interspaces are the site of osteophytic compression, their removal by an anterior approach (anterior cervical discectomy with [or without] fixation, or “ACDF”) has given better results and carries less risk. Braakman has reviewed the surgical methods and their relative advantages.
Even with modern surgical techniques, most series indicate that once symptomatic, the outcome varies and that a significant proportion of patients, even after adequate decompression and initial improvement, have persistent symptoms or undergo some degree of later functional deterioration (see also Chap. 10). This creates a conundrum for the physician in advising the patient about the correct time to undertake surgical decompression. Nonetheless, certain clinical observations pertain and may be used as guides to treatment. Any degree of spasticity, sphincter disturbance, or loss of sensation in the hands will not improve or will improve little, and indeed usually worsens over months, without surgery. Hand weakness and muscular atrophy that is the result of radicular compression will improve with decompression of the appropriate root by one of several surgical approaches, but weakness that is from central cord damage requires decompression to halt the process and probably should not be delayed more than a few weeks once it is apparent that this is the problem. Usually, such patients have MRI signal changes within the substance of the cervical cord in apposition to an osteophytic bar.
Lumbar Stenosis (See Chap. 10)
This is another spondylotic abnormality seen with particular frequency in older individuals, especially men. Usually it declares itself by numbness and weakness of the legs, sometime with poor control of sphincters. Many texts state that there may be little or no pain or only a spinal ache that fluctuates from day to day but in our experience the majority of patients have constant backache and sciatica. A notable feature is the induction or aggravation of the neurologic symptoms upon standing and walking (neurologic claudication). This topic is discussed in “Lumbar Stenosis” in Chap. 10, which should be consulted for a detailed discussion.
This condition of the spine is a result of inflammation at the sites of ligamentous insertions into bone that leads to an intense calcification. The sacroiliac joints and lumbar spine are most affected, as discussed in Chap. 10, but as the disease advances, the entire spine becomes fused and rigid. The biomechanics of the rigid spine make it susceptible to fracture. The most common complication is a spinal stenosis and cauda equina syndrome. Bartleson and associates described 14 patients (and referred to 30 others in the medical literature) who, years after the onset of spondylitis, developed sensory, motor, reflex, and sphincteric disorders referable to L4, L5, and the sacral roots. Surprisingly, the spinal canal was not narrowed but instead the caudal sac was actually dilated. Confavreux and coworkers presented evidence that enlargement of the lumbar dural sac is caused by a defect in resorption of the CSF. There are usually arachnoidal diverticula on the posterior root sleeves, but no other explanation can be given for the radicular symptoms and signs. Surgical decompression has not benefited most patients, nor has corticosteroid therapy.
This condition occasionally occurs at higher levels and gives rise to a myelopathy. Our experience includes several cases with symptoms related to the cervical roots.