What DCs Should Know about Cervical Degenerative Disease
Neck pain is already a common reason patients see their D.C.s. As the population ages, more cases of spondylosis, compressive myelopathy and radiculopathy are likely. Dr. Don Aspegren shares his insights to help you identify these conditions and potentially avoid a “failure to diagnose” allegation.
Posted in Risk Management on Thursday, March 1, 2018
Many chiropractic patients have cervical spine pathology and/or peripheral neuromusculoskeletal complaints, and cervical degenerative disease is likely to be increasingly common in chiropractic patients.
Cervical degenerative disease with spondylotic changes may evolve into conditions that compress the spinal cord and/or nerve roots. Spinal cord compression in the cervical region of one or more levels with symptom manifestation may be referred to as cervical compressive myelopathy (CCM) or cervical spondylotic myelopathy (CSM).
Radicular symptoms can result from involvement of the nerve roots from degenerative cervical changes. Myelopathy with cord compression may occur separately or at the same time as nerve root involvement. If so, the condition is called radiculomyelopathy.1-3
It’s important to monitor the neurological status of patients who may progress from radicular to myelopathy symptoms. Then, refer the patient as appropriate when neurological findings progress. As these conditions may be age related, you may notice a slow, intermittent progression. It may be very gradual but will commonly have very distinct findings. Adverse changes may be noted in sensory, motor and autonomic nervous system function.
CCM/CSM is the most common myelopathy, which can be caused by the narrowing of the spinal canal from stenosis, spondylosis, ossification of the posterior longitudinal ligament, intervertebral disc herniation or tumors. As a result of the cord compression, intraspinal cord pressure increases, which can lead to patients presenting with various symptoms.
Some patients will report neck pain, upper and lower extremity paresthesia, muscle weakness or spasticity, altered gait patterns with imbalance, lower extremity stiffness and jerking, upper and/or lower extremity sensory loss, clumsiness including fine motor skills, bowel, bladder, and sexual dysfunction.4,5 These symptoms can be caused by problems in the sensory, motor and the autonomic nervous systems.6
Symptoms typically present after age 40 and most commonly between 50 and 70. Onset is typically insidious but may be associated with trauma. Men are more frequently afflicted than women by a ratio of 3:2. 7
The exam may reveal upper motor neuron pathology findings. The patient may have increased deep tendon reflexes in the upper and/or lower extremities that you may observe with a very light stroking of the tendon. Hoffman’s reflex is positive with flicking of the middle finger causing flexion of the thumb and/or index finger. A positive Babinski sign may be present even though the compression is in the cervical region. You may also notice sensory loss in lower and/or upper extremities, as well as spasticity in arms and/or legs.
Individuals with CCM/CSM also may demonstrate gait dysfunction. The patient’s gait may become slower and stride length shorter. If you observe the patient walking from behind, you may notice a slightly wider step as the patient attempts to increase stability.8
In contrast, compression and/or inflammation of one or more spinal nerve roots may cause radiculopathy without the myelopathy component. You’ll typically see symptoms include radiation of pain and paresthesia into the extremity, with clinical signs of lower motor neuron involvement. It is different from CSM where degenerative spondylotic changes encroaching into the spinal canal is the most common etiology. In a radiculopathy, a herniated intervertebral disc is the most common cause.
MRI is one of the most useful tools in identifying CCM/CSM or disc herniation. MRI findings will include spondylotic changes, congenital stenosis of the spinal canal or encroachment of the intervertebral foramen, and status of the spinal cord. The extent of osteophytic development into the various foramen provide understanding of the adverse neural changes. Other pathologies may mimic CCM, such as myelopathy caused by tumors, various types of infection and other space-occupying lesions capable of cord compression. The MRI will help evaluate for these pathologies. If MRI cannot be used, you may find a CT myelography scan helpful, and it may be needed if the MRI is inconclusive.
Plain film X-rays can be beneficial, as well. The most useful view may be the lateral projection, which can be used to assess for spinal canal narrowing. A minimum AP measurement of the spinal canal is 11 mm: measurements of 11 mm or less are highly suggestive of cord compression.
In addition to measuring the actual anterior to posterior distance of the canal, you may find it helpful to use a ratio commonly discussed when assessing the patient for potential spinal stenosis. The Torg ratio is helpful when projectional Xray magnification is a concern in measuring the canal. With the Torg ratio, magnification is of less concern. To obtain a Torg ratio, measure the midsagital diameter of the spinal canal from the middle of the posterior aspect of the vertebral body to the spinolaminar line of the same vertebral segment. This measurement is divided by the AP diameter of the middle of the same vertebral body. Normal ratio measurement is 1.0. If the measurement is less than 0.8, it would suggest stenosis. Stenotic patients will be at more risk of developing CCM/CSM.7
Prudent Clinical Decisions are Good Risk Management
When treating patients with cervical pathologies, be alert for potential crossover from radiculopathies into cervical compressive myelopathy. Using historical information, physical examination and imaging findings can help you monitor case progression and determine the therapeutic approach—and refer the patient for additional care as needed. In doing so, you are not only focusing on patient care, but also minimizing the risk of failing to diagnose a serious condition.