Herniation of a Cervical Intervertebral Disk

HERNIATION OF A CERVICAL INTERVERTEBRAL DISK

The cervical spine is subjected to stresses that result from disk de-generation (from aging, occupational stresses) and spondylosis (degenerative changes occurring in disk and adjacent vertebral bodies). Cervical disk degeneration may lead to lesions that can cause damage to the spinal cord and its roots.

A cervical disk herniation usually occurs at the C5-6 and C6-7 interspaces. Pain and stiffness may occur in the neck, the top of the shoulders, and the region of the scapulae. Sometimes patients interpret these signs as symptoms of heart trouble or bursitis. Pain may also occur in the upper extremities and head, accompanied by paresthesia (tingling or a “pins and needles” sensation) and numbness of the upper extremities. Cervical MRI usually confirms the diagnosis.

Medical Management

The goals of treatment are (1) to rest and immobilize the cervical spine to give the soft tissues time to heal and (2) to reduce in-flammation in the supporting tissues and the affected nerve roots in the cervical spine. Bed rest (usually 1 to 2 days) is important because it eliminates the stress of gravity and relieves the cervical spine from the need to support the head. It also reduces inflam-mation and edema in soft tissues around the disk, relieving pres-sure on the nerve roots. Proper positioning on a firm mattress may bring dramatic relief from pain.

The cervical spine may be rested and immobilized by a cervi-cal collar, cervical traction, or a brace. A collar allows maximal opening of the intervertebral foramina and holds the head in a neutral or slightly flexed position. The patient may have to wear the collar 24 hours a day during the acute phase. The skin under the collar is inspected for irritation. When the patient is free of pain, cervical isometric exercises are started to strengthen the neck muscles.

Cervical traction is accomplished by means of a head halter at-tached to a pulley and weight. It increases vertebral separation and thus relieves pressure on the nerve roots. The head of the bed is elevated to provide countertraction. If the skin becomes irritated, the halter can be padded. Experience hasshown that a male patient may suffer more skin irritation if he shaves; the beard offers a natural form of padding.

PHARMACOLOGIC THERAPY

Analgesic agents (NSAIDs, propoxyphene [Darvon], oxycodone [Tylox], or hydrocodone [Vicodin]) are prescribed during the acute phase to relieve pain, and sedatives may be administered to control the anxiety often associated with cervical disk disease. Muscle relaxants (cyclobenzaprine [Flexeril], methocarbamol [Robaxin], metaxalone [Skelaxin]) are administered to interrupt the cycle of muscle spasm and to promote comfort. NSAIDs (as-pirin, ibuprofen [Motrin, Advil], naproxen [Naprosyn, Anaprox]) or corticosteroids are prescribed to treat the inflammatory re-sponse that usually occurs in the supporting tissues and affected nerve roots. Occasionally, an injection of a corticosteroid into the epidural space may be administered for relief of radicular (spinal nerve root) pain. NSAIDs are given with food and antacids to prevent gastrointestinal irritation. Hot, moist compresses (for 10 to 20 minutes) applied to the back of the neck several times daily increase blood flow to the muscles and help relax the spastic muscles and the patient.

SURGICAL MANAGEMENT

Surgical excision of the herniated disk may be necessary when there is a significant neurologic deficit, progression of the deficit, evidence of cord compression, or pain that either worsens or fails to improve. A cervical discectomy, with or without fusion, may be performed to alleviate symptoms. An anterior surgical ap-proach may be used through a transverse incision to remove disk material that has herniated into the spinal canal and foramina, or a posterior approach may be used at the appropriate level of the cervical spine. Potential complications with the anterior approach include carotid or vertebral artery injury, recurrent laryngeal nerve dysfunction, esophageal perforation, and airway obstruc-tion. Complications of the posterior approach include damage to the nerve root or the spinal cord due to retraction or contusion of either of these structures, resulting in weakness of muscles sup-plied by the nerve root or cord.

Microsurgery, such as endoscopic microdiscectomy, may be performed in selected patients through a small incision and using magnification techniques. The patient who undergoes micro-surgery usually has less tissue trauma and pain and consequently a shorter hospital stay than after conventional surgical approaches.