J. Paul Elliott and Anthony P. Dwyer

Goals of Surgical Treatment

To decompress the cervical spinal cord and nerve roots and provide effective instrumentation and fusion of the spine when it is unstable.

Diagnosis

Accurate diagnosis depends on correlation of the salient clinical history, directed physical examination, diagnostic radiographic studies, and selective electrophysiologic evaluation.

Radiographic Evaluation

Minimal radiographic evaluation should include axial and sagittal cervical magnetic resonance imaging (MRI) scans, and flexion and extension radiographs. The MRI facilitates assessment of global spinal alignment, identification of the level of anatomic stenosis, detection of the presence of abnormal cervical spinal cord signal, and assessment of nerve root compression secondary to foraminal stenosis. The MRI evaluation should include axial cuts throughout the entire cervical spine. Flexion-extension x-rays should be performed when the patient is minimally symptomatic or following adequate analgesia to allow for maximal range of motion. The patient should be assessed for abnormal movement with attention to cervical body translation, change in canal diameter, and facet and interspinous widening. Flexion-extension x-rays should be done with caution if gross instability is suspected or there has been recent trauma.

Radiographic studies facilitate identification of (1) levels of cervical cord compression, (2) levels of foraminal stenosis, and (3) presence of instability with flexion or extension. Levels of cord compression consistent with myelopathy and foramina stenosis consistent with radiculopathy should be correlated with clinical diagnosis based on history and physical examination.

Indications for Surgery

There are both absolute and relative indications for posterior decompression with or without fusion.

1. Progressive symptomatic cervical myelopathy requires surgical decompression.

2. The levels of involvement, degree of anterior versus posterior compression, and degree of maintenance of normal cervical lordosis determine whether a posterior (laminectomy) or anterior (multilevel discectomy/ fusion or corpectomy/reconstruction) approach should be used.

3. Generally, posterior decompression using laminectomy and foraminotomies is used for focal or multilevel compression where there is maintained cervical lordosis. Instrumentation and fusion is reserved for cases where instability is demonstrated on preoperative flexion-extension cervical spine radiography or when adequate decompression requires stabilization of the posterior spinal elements.

Contraindications for Surgery

1. Cervical kyphosis.

2. Significant loss of lordosis or primarily anterior spinal cord compression.

3. In cases of posterior compression with loss of lordosis or kyphosis, decompression without stabilization should usually be avoided.

Advantages

1. Posterior decompression is a rapid, safe, and efficacious procedure in experienced hands.

2. Iatrogenic destabilization is rare if the facet joints are preserved.

3. When needed, instrumentation with lateral mass screws and plates provides immediate and effective stabilization until fusion is achieved.

Disadvantages

1. Compared to anterior cervical surgery, there is increased perioperative pain, with an extended recovery time.

2. There is a risk of delayed swan-neck deformity following posterior decompression without fusion.

Surgical Procedure