Cervical myelopathy

In one minute

Degenerative cervical myelopathy (DCM) is the spinal cord in the neck malfunctioning because it is being squeezed by worn discs, bone spurs, thickened or ossified ligaments, or a narrow canal. The 2017 AO Spine and CSRS (Cervical Spine Research Society) guideline calls it the most common cause of spinal cord dysfunction in adults worldwide. Most patients are first diagnosed in their 50s; it is uncommon before 40. It feels like numb, clumsy hands that fumble buttons, stiff or heavy legs, unsteady walking and falls, sometimes bladder urgency; neck pain may be mild or absent. It is diagnosed by a full neurological examination and an MRI (magnetic resonance imaging) of the neck, and graded on the mJOA (modified Japanese Orthopaedic Association) scale. The guideline recommends surgery for moderate and severe disease and offers surgery or supervised rehabilitation for mild disease, with surgery if it worsens. Our team performs these decompressions, including multilevel cervical operations.

What it is

The spinal cord is the cable that carries every instruction to the arms and legs and every sensation back. In the neck it runs through a canal formed by the vertebral bodies and discs in front and the bony arches and ligaments behind. Myelopathy means the cord itself is not working properly; degenerative means the cause is wear rather than injury, tumour or inflammation. DCM, which the BMJ review notes was earlier called cervical spondylotic myelopathy, is the umbrella for cord compression from spurs and discs, disc herniation, thickened ligaments and OPLL (ossification of the posterior longitudinal ligament), because they compress the cord in the same way and are treated on the same principles. Patients often meet the diagnosis as cord compression, spinal stenosis with myelopathy, or, in Russian-language reports, cervical osteochondrosis with myelopathy.

Causes and risk factors

Age and wear are the main drivers. The BMJ review of 2018 places most first diagnoses in the 50s and estimates the prevalence of surgically treated DCM at 1.6 per 100,000, while noting that the true prevalence is likely much higher because many cases go undiagnosed. A congenitally narrow canal, a large disc herniation, OPLL and a neck that has lost its curve all use up the cord's reserve sooner. In the prediction model built on 743 patients from the AOSpine North American and international cohorts, the strongest predictors of surgical outcome were baseline severity, age, smoking and impaired gait, with smoking roughly halving the odds of a good result in both datasets. Delay is a risk factor in its own right: in a series of 42 surgical patients cited in the BMJ review, the average delay from first symptom to diagnosis was 2.2 years and 5.2 consultations, and 43% had first been diagnosed with carpal tunnel syndrome.

How it develops

When the fluid cushion around the cord is gone, the cord is squeezed statically by whatever presses on it and dynamically each time the neck bends or extends, a distinction the guideline uses when it discusses which cases respond to nonoperative care. The long tracts that carry fine hand control and balance suffer first, which is why buttons and stairs fail before anything else. The BMJ review is blunt about the consequence: cord compression results in progressive neurological decline, the regenerative capacity of the cord is limited, and damage is often permanent. Untreated, the disease does not usually sit still. The systematic review behind the guideline found moderate evidence that 20% to 62% of patients with symptomatic myelopathy deteriorate by at least one point on the JOA (Japanese Orthopaedic Association) scale within 3 to 6 years. The rate varies: the BMJ review notes that some stay mild for a long time while others accelerate, and the guideline calls the natural history variable from patient to patient.

Symptoms

The BMJ review lists the common complaints: neck pain or stiffness, pain in the limbs, weakness, numbness or loss of dexterity in the arms, stiffness, weakness or sensory loss in the legs, tingling, imbalance and falls, and autonomic symptoms such as bladder or bowel incontinence or difficulty passing urine. Loss of dexterity shows up as trouble with buttons, keys, phones and handwriting; loss of mobility as walking aids and falls. Pain can be absent. Symptoms may be one-sided and vary from day to day, and the more consistent feature is that they have been evolving for months. On examination the doctor looks for brisk reflexes, a Hoffmann sign, an upgoing toe, clonus, weakness in a particular pattern and a broad or stiff gait. These signs have low sensitivity and high specificity: a normal examination does not rule the disease out, an abnormal one strongly suggests it.

Diagnosis

Two steps: a full neurological examination that finds the signs above, and an MRI of the cervical spine that shows compression of the cord at a level that explains them. The BMJ review calls MRI essential, urgent when symptoms are progressing or disabling, and warns that the degree of compression and the bright signal inside the cord on T2 images do not correlate well with the severity of symptoms; even mild compression can account for severe disease. CT (computed tomography) is added when OPLL is suspected, because it shows bone better.

Severity is graded on the mJOA scale, which scores hand function, walking, sensation and bladder control from 0 to 18. The 2017 guideline defines 15 to 17 as mild, 12 to 14 as moderate and 11 or below as severe. The grade decides the recommendation, so describe each of those four domains when you send the scan. One trap is worth naming: the BMJ authors write that in their experience a diagnosis of carpal tunnel syndrome, especially when made in both hands, is often incorrect and DCM usually accounts for the symptoms. When you send an MRI, add the report, the side-view T2 images and the cross-sections at the tightest level, and a short video of you walking and doing up a button.

Treatment without surgery

The systematic review of nonoperative management found little evidence in its favour. In two cohort studies, patients with moderate to severe myelopathy did worse without surgery than with it, even though the surgical patients started off worse; in one randomised trial of mild myelopathy there was low-quality evidence that nonoperative care gave equivalent or better results. Its recommendation was not to routinely prescribe nonoperative treatment as the primary strategy in moderate to severe myelopathy, and, if nonoperative care is chosen for mild disease, to watch closely for deterioration. The 2017 guideline accordingly offers a supervised trial of structured rehabilitation as one option for mild disease only. Symptom control still matters: the BMJ review mentions neuropathic pain medication and anti-spasticity medication, prescribed by the doctor, and early referral to a specialist pain clinic when pain persists. It also states that neck manipulation is strictly contraindicated and that preoperative physiotherapy should be advised only by specialist services. Collars, traction and injections do not decompress the cord.

When surgery is considered

The 2017 guideline is the reference. It recommends surgery for severe DCM (mJOA 0 to 11) and for moderate DCM (mJOA 12 to 14), both strong recommendations on moderate-quality evidence. For mild DCM (mJOA 15 to 17) it suggests offering surgery or a supervised trial of structured rehabilitation; if nonoperative care is chosen, it recommends surgery if there is neurological deterioration and suggests surgery if the patient fails to improve. For cord compression without myelopathy it suggests not offering prophylactic surgery, and for cord compression with radiculopathy it advises counselling about the higher risk and offering either surgery or close follow-up.

On timing, the guideline reports that a longer duration of symptoms and more severe myelopathy both reduce a patient's odds of reaching an mJOA of 16 or more, and advises that patients with progressive myelopathy be referred immediately for surgical consultation regardless of baseline severity. The BMJ review adds that in the AOSpine analysis of 746 patients, recovery was most likely when treatment came within six months of symptoms. That is why this condition does not usually wait: not because the operation is urgent to the day, but because every month of compression is a month the cord may not get back.

Surgical options

Anterior decompression and fusion

When the compression sits in front of the cord, from a disc-spur complex or OPLL, or the neck has lost its forward curve, the disc (discectomy) or part of the vertebral body (corpectomy) is removed from the front and the levels are fused with cages or a graft and a plate. ACDF (anterior cervical discectomy and fusion) is the usual choice at one to three levels.

Posterior decompression: laminoplasty or laminectomy with fusion

When three or more levels are compressed from behind and the neck keeps its curve, the bony arches are hinged open (laminoplasty) or removed (laminectomy), sometimes with screws. These are open operations with a longer recovery.

Endoscopic posterior cervical decompression

A laminotomy through a 7 mm incision that thins the arch and removes thickened or calcified ligament, for compression from behind at one or two levels in a well-aligned neck, without screws or implants. The evidence is early: a 2023 systematic review pooled 183 patients treated with full-endoscopic anterior transcorporeal or posterior techniques, with indications including central canal stenosis, calcified ligamentum flavum, OPLL and disc herniation, a mean hospital stay of 3.56 days, significant functional improvement and no major complications at a mean follow-up of 18.7 months. Small numbers, selected patients, and we say so. See endoscopic cervical decompression.

Whatever the route, the guideline's pooled review found a cumulative complication incidence of 14.1% for surgery in DCM, with C5 nerve palsy in 1.9%, infection in 1.5%, dural tear in 1.4%, worsening of myelopathy in 1.3%, reoperation in 1.4% and death in 0.3%.

How we treat it at spine.uz

We are Tashkent's first endoscopic spine team: five surgeons operating as one team, trained in South Korea, Japan, Germany and the USA, with 27,600+ endoscopic and spine operations between us. The team operates on all levels, including multilevel cervical cases. The first step costs nothing: send the MRI, the report and a short video of your walking on Telegram or WhatsApp, and a doctor from the team replies by voice within 48 hours. The in-person consultation and any operation are paid.

The team performs the posterior endoscopic decompression through a 7 mm incision without screws or implants, ACDF and multilevel cervical operations; which route fits follows the logic set out under surgical options. Most of our endoscopic decompressions are done under local anaesthesia with sedation, the anaesthetist and surgeon deciding per patient, and most patients walk the same day and go home within 24 hours. Across the team's operations our complication rate is well below 1%. No surgeon can promise that lost function returns. Every patient leaves with a written team conclusion.

Recovery and outcomes

Surgery usually improves the picture and usually falls short of a full cure. In the AOSpine North America study of 278 patients at 12 centres, function, disability and quality of life improved at one year across mild, moderate and severe groups, with complications in 18.7% and no difference between severities. In the international study of 479 patients at 16 sites, the mean mJOA improved from 12.50 to 14.90 at two years and the Neck Disability Index from 36.38 to 23.20, with neurological complications in 3.13%. The BMJ review sets expectations: maximal recovery occurs at around 6 to 12 months, residual symptoms beyond that are likely to be permanent, complete resolution of pain is unlikely, and problems such as falls, incontinence, sleep loss and depression are common and need managing. What improves the odds, from the prediction model, is being operated on with a higher baseline score, after a shorter duration of symptoms, at a younger age, as a non-smoker and before walking is impaired: in the authors' own worked application of the model, impaired gait predicts a worse outcome.

Living with it and prevention

Stop smoking; it roughly halved the odds of a good surgical outcome in both AOSpine datasets. Prevent falls at home. Avoid neck manipulation. Report any new weakness, numbness or change in walking promptly, because untreated levels can degenerate and compress the cord again. And if a relative over 50 has started to fumble buttons and walk unsteadily, send their scan before someone treats their hands.