Technical Challenges

William Dillin

Goals of Surgical Treatment

To alleviate cervical nerve root generated arm pain and/or weakness secondary to mechanical pressure from a disc herniation or osteophyte. To remove mechanical pressure on the spinal cord secondary to posterior osteophytes at the disc space level or a herniated disc.

Diagnosis

Cervical Radiculopathy

1. The diagnosis is made on the basis of the history and physical and diagnostic studies.

2. The most reliable history for cervical nerve root compression is the development of arm pain, arm weakness, or numbness in the distribution of a single nerve root.

3. The physical examination may reveal a specific motor deficit or sensory deficit.

4. The arm pain often is exacerbated with hyperextension of the neck and rotation to the involved sign. This arm pain may be relieved by shoulder abduction.

5. Imaging studies such as a magnetic resonance imaging (MRI) scan may reveal an unequivocal structural abnormality (disc herniation, osteophyte, foraminal stenosis) correlating with the patient’s clinical complaints and physical examination.

6. Other studies may be necessary, however, to confirm the presence of pathologic correlate and a symptomatic nerve root. This could include a cervical myelogram, combined with a contrast-enhanced computed axial tomography (CAT).

Cervical Myelopathy

1. The diagnosis is made on the basis of the history and physical and diagnostic studies.

2. The most reliable history for spinal cord compression is the development of a sense of balance loss, unsteadiness of gait, or unusual sensory disturbances in the lower extremities.

3. Upper extremity involvement may involve numb, clumsy hands or a radicular component.

4. The physical examination may reveal a hyperactive reflexes, nondermatomal sensory changes, and pathologic reflexes (Babinski, Hoffman’s). Myelopathy in its earlier stages, however, may not reveal symptoms on physical examination.

5. Neck motion may produce a shock-like feeling in the torso or extremities.

6. Imaging studies such as an MRI scan may reveal an unequivocal structural abnormality (disc herniation, osteophyte) with spinal cord compression.

Indications for Surgery

1. Cervical radiculopathy with compression at the interspace level

2. Cervical myelopathy with compression at the interspace level

3. Unacceptable arm pain

4. Progressive symptoms with a gait disorder

5. Progressive weakness in involved upper extremity

6. Progressive symptoms with numb, clumsy hands

7. Loss of control of bowel and bladder symptoms

8. Cord syndromes such as an anterior cord syndrome, central cord syndrome, Brown-SUquard syndrome

Contraindications

1. Posterior pathology as the compressive agent.

2. Patient is not a candidate for surgery because of medical reasons.

Advantages

1. Direct visualized decompression of the offending pathology, which is commonly located anteriorly.

2. Indirect decompression with restoration or amplification of disc space height, which may increase foraminal size, and canal size.

Disadvantages

1. The potential for further destabilization of a motion segment in the spine at an adjacent level, leading to pain and disability and possible further surgery.

2. The anterior approach involves structures that might be infringed upon: recurrent laryngeal nerve, the trachea, the sympathetic trunk, the vagus nerve, the carotid sheath, the internal jugular vein.

Procedure

Technical Goal

To decompress the cervical spinal nerve and/or spinal cord due to a disc herniation or osteophyte.

Technical Challenge

Precision surgery aided by magnification and illumination.

Technical Principles

1. Approach to establish safe and secured anatomic plane for decompression and fusion.

2. Maintain optimum access to provide adequate decompression and stabilization.

Decision Making

1. Is the pathology actually represented on the preoperative films discovered in the operation?

2. Is the patient adequately decompressed?

Position and Exposure

1. Supine position, chest roll under posterior upper back to facilitate a neck neutral to slightly extended position. Radiolucent table to facilitate use of fluoroscopy in surgery. Arms tucked in at side, Boger straps placed but not tightened to provide visualization of C7 when needed for intraoperative x-ray.

2. Hypotensive anesthesia to reduce bleeding.

3. Preincision x-ray with sterile paper clip used as marker if there is any doubt about landmarks.