Cervical Stenosis & Myelopathy
What is It? What Treatments Are Available?
The cervical spine (neck) is made up of a series of connected bones called vertebrae. The bones protect the spinal canal that runs through the vertebrae and carries the spinal cord. The spinal cord contains nerves that give strength and sensation to the arms and legs, and provide bowel and bladder control. Numerous connections (discs, joints, ligaments and muscles) between the cervical vertebrae provide support, stability and allow motion.
With age, intervertebral discs become less spongy and lose water content. This can lead to reduced disc height and bulging of the hardened disc into the spinal canal. The bones and ligaments of the spinal joints thicken and enlarge, also pushing into the spinal canal. These changes are common after age 50 and are generally called “cervical spondylosis” or “cervical stenosis.”
Cervical stenosis may occur at a very slow or very fast rate. These changes cause narrowing of the spinal canal and can pinch the spinal cord and nerve roots. Spinal cord or nerve function may be affected, causing symptoms of cervical radiculopathy or myelopathy. (Cervical stenosis is the name for the actual narrowing of the canal, while cervical myelopathy indicates injury to the spinal cord and its function.)
What are the Symptoms?
Stenosis does not necessarily cause symptoms; if symptoms do appear, they usually indicate the presence of radiculopathy or myelopathy.
About half of patients with cervical myelopathy have pain in their neck or arms; most have symptoms of arm and leg dysfunction. Arm symptoms may include weakness, stiffness or clumsiness in the hands, such as being unable to button a shirt, turn a doorknob or open a jar. Leg symptoms may include weakness, difficulty walking, frequent falls or the need to use a cane or walker as the disease progresses.
Urinary urgency is also common. In late cases, bladder and bowel incontinence can occur.
Symptom progression may also vary. You may:
* experience a slow, steady decline;
* progress to a certain point and become stable; or
* progress rapidly.
The first signs are often increased knee and ankle reflexes. These may only be detected in a neurologic exam. Early detection is important to determine treatment which may help slow symptom progression.
How is It Diagnosed?
Your doctor will begin by asking you questions and performing a physical examination, and may order tests. In addition to the symptoms you describe to your doctor, a physical examination may reveal other findings such as:
* increased reflexes in the knee and ankle, called hyperreflexia, sometimes found with depressed reflexes in the arms;
* changes in your gait (walk) such as clumsiness or loss of balance; and
* loss of sensitivity in the hands and/or feet, sometimes making it difficult to button a shirt or sense a change in the position of your feet.
Other findings include rapid foot beating triggered by turning the ankle upward (clonus), extension of the big toe when the foot is stroked (Babinski’s sign), contraction of the thumb and index finger after flipping of the middle finger (Hoffman’s sign). One or several of these findings may lead your doctor to suspect spinal cord dysfunction. Range of motion or flexibility of the neck often decrease with age and does not necessarily indicate nerve or spinal cord dysfunction.
Cervical spine X-rays may not provide enough information to confirm cervical stenosis, but may rule out other conditions. Magnetic resonance imaging (MRI) is often used. MRI images are very detailed and show the tight spinal canal and pinching of the spinal cord. Cervical stenosis (narrowing of the spinal canal) and myelopathy can occur at one level or many levels of the spine and MRI is useful for looking at several levels at one time. A computed tomography (CT) scan may give clearer information about bony invasion of the canal and can be combined with an injection of dye into the fluid around the spinal cord and nerves (myelography).
Electrical studies assess or distinguish between myelopathy and other conditions. Electromyography (EMG) and nerve conduction velocity (NCV) may help rule out peripheral nerve problems such as a pinched nerve in your neck or arm that can cause symptoms like those of myelopathy. Somatosensory Evoked Potentials (SSEP) testing is done by stimulating the arms and/or legs and reading a signal in the brain. A delay in the length of time it takes the signal to reach the brain can indicate spinal cord compromise. This study may also rule out other disorders that may be confused with myelopathy. http://www.spine.org/articles/cervicalstenosis.cfm