A posterolateral approach to occipitoatlantoaxial ventral lesions: a report of the long-term follow-up of 23 cases.

STUDY DESIGN

A retrospective study of consecutive patient series.

OBJECTIVES

To report a technique of odontoidectomy using a transoccipitocervical posterolateral approach for occipitoatlantoaxial ventral lesions in a long-term follow-up study.

SUMMARY OF BACKGROUND DATA

Occipitoatlantoaxial malformation and old traumatic dislocation usually cause compression of the high cervical spinal cord from a variety of different directions and angles, leading to high morbidity. The main objective of treatment is to relieve the anteroposterior compression and to restore the stability of the occipitocervical region. Currently, there are 2 approaches to perform the surgical procedure: (1) posterior decompression by suboccipital and occipitocervical fusion and internal fixation; and (2) decompression by a transoral approach to an odontoid resection. However, there are some short points, which need to be changed, such as the incomplete decompression (the former), narrow view, cerebrospinal fluid leakage, and the high infection rates.

METHODS

From 1999 to 2006, 23 patients with occipitoatlantoaxial ventral lesions were treated using a transoccipitocervical posterolateral approach for decompression. The procedure included an expansion of the foramen magnum, a resection of the posterior arch of atlas, a lateral occipitocervical epidural exposure to the odontoid and the C2 vertebra, and an excision of the odontoid. Thus, an anteroposterior decompression and occipitocervical spinal fusion was achieved. Neurological function, daily living ability, and the work ability of patients were assessed in a follow-up study.

RESULTS

A 28-year-old woman died of respiratory and circulatory failure 10 hours after operation. The remaining patients survived without postoperative infection. The neurological injury in 17 patients did not deteriorate, whereas 5 patients had decreased sensation in the upper limbs, and the elbow flexor muscle strength in 2 patients declined by 1 grade on the operation side. Short-term follow-up (3-6 mo, 22 cases) indicated that 19 patients recovered normal sensation with decreased limb muscle tension. Motor function was improved by >1 grade (5 patients with postoperative nerve injury recovered to preoperative levels or better). Long-term follow-up (>4 y) of 15 patients (10 patients by clinic visit and 5 patients by correspondence) indicated that the occipitoatlantoaxial regions were stable without local discomfort or loss of nerve function. Fourteen patients were able to care for themselves and some patients regained their ability to work. One patient felt no significant improvement after surgery and had no improvement in the quality of life.

CONCLUSIONS

Transoccipitocervical posterolateral approach to occipitoatlantoaxial ventral lesions provides a broad and sterile operating field to perform anteroposterior decompression and occipitocervical spinal fusion simultaneously. Neurological improvement is significant, and the long-term follow-up results are satisfactory.