PERSPECTIVE
Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction in adults in Western society. Very little has been written about it in Nigeria. This would give the impression that it is rare in Nigeria. Unfortunately, this is not the case and having seen a few patients now in Abuja, we can appreciate some of the real issues.
Patients with cervical spondylotic myelopathy are not being properly diagnosed and managed. It is often thought to be a disease of old age and part of life. Others feel that old age and infirmity precludes management and so patients are not referred to hospital. Families also at times prefer local management with traditional healers. Finally, patients are often treated only by general practitioners, general medicine physicians and neurologists. We have now seen a few patients who have been treated long term for CSM by neurologists without referral for surgical intervention. Patients having been seen are placed on long term steroid therapy, vitamin C and analgesics and neuropathic pain medicines such as Carbamazepine, Gabapentin and Pregabalin. Our perspective is that such treatment especially for moderate or severe CSM is of little benefit to address the fundamental and underlying problem in CSM. In our opinion, steroid use is not necessary and predisposes patients to diabetes, osteoporosis and avascular necrosis of the head of femur. The other two key problems in the past were poor availability of MRI scans and spine trained neurosurgeons.
Cervical Spondylotic Myelopathy
Cervical spondylotic myelopathy is a serious consequence of cervical intervertebral disc degeneration and ligamentous hypertrophy. In these patients, the diagnosis should be established on the basis of both neurological examination and Magnetic Resonance Imaging (MRI). Symptoms range from chronic neck pain, headache, radicular pain down the arms or down the spine, to myelopathy leading to weakness, numbness, impaired fine motor coordination, mono/ quadriparesis and/or sphincter dysfunction. MRI findings that should show spinal cord compression and myelomalacia (see figure 1, 2 and 3).
The management of cervical myelopathy is informed by an MRI scan or CT myelography. Even ordinary contrast enhanced CT scan can be of benefit. Plain x-ray is not diagnostic and cannot be used as a standalone investigation. It is however important to show spinal alignment, bone quality and other diagnosis such as cancer or infections, for example, tuberculosis. An MRI scan is the gold standard investigative modality. It shows the cause of the myelopathy whether due to anterior disc prolapse, osterophytes or posteriorly based compression from ligamentous hypertrophy. MRI also shows up evidence of damage to the spinal cord (myelomalacia). In this regard, the presence of myelomalacia (hyper intensity) of the cord is an important radiological sign.
Cervical spondylotic myelopathy is one of the most common disorders treated by spine surgeons who could be orthopaedic or neurosurgical trained experts. Patients can be treated from an anterior or posterior approach. With the pressure from anterior, we adopt an anterior approach on principle. While for patients with the pressure of spinal cord from posterior elements such as ligamentous hypertrophy, the best approach may be from the back. The anterior operation is often an anterior cervical discectomy and fusion. The posterior approach is often a laminectomy or modifications thereof.
Surgical decompression remains the mainstay of management of CSM once myelopathy develops. Both anterior and posterior approaches have fine effect to the treatment of CSM. Patients treated with surgery have better neurological recovery, less axial neck pain, and lower incidences of loss of sagittal plane alignment. But the selection of the patient and a clear definition of the indication for surgery are very important. Assessment of the patient, determination of the surgical approach and a realistic objective is also crucial. It is treatable and the condition is reversible in some cases, if caught before permanent cord damage had occurred.
Despite continued increases in patient medical co-morbidities, overall complication rates are around 10.3% and mortality rates are less than 1%. Treatment of mild CSM may involve surgical decompression or nonoperative therapy for the first 3 years after diagnosis. More severe CSM should be considered for surgery depending upon the individual case.
Conclusion
It is not a disease of old age and should not be ignored. It is treatable and the condition may be significantly improved. Please note that MRI scans are now fairly available and should be insisted upon in patients with the symptomatology and signs suggestive of CSM. Likewise, it is imperative that a team based approach to management is instituted for the patient. The team must include a neurosurgeon and a physiotherapist. General practitioners and neurologists who suspect CSM should obtain an MRI scan and identify a local neurosurgeon who should be asked for an opinion on the case. Insist on early consideration for surgical intervention. Patients should then be counselled on the short term expectations and long term outcome. Steroid use is of no real benefit in management of patients with moderate or severe Cervical Spondylotic Myelopathy.
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