Introduction: Occipitocervical junction instability can lead to serious neurologic injury or death if left untreated. Open surgical fixation is often necessary in order to provide definitive stabilization.

Methods: The charts of all patients undergoing posterior internal fixation by the senior author were retrospectively reviewed. One hundred and twenty consecutive patients were identified for analysis. Patient demographics, occipitocervical junction pathology, surgical indications, clinical and radiographic outcomes are reported.

Results: The study population consisted of 64 males and 56 females, mean age of 39.9 years (range 7 months - 88 years). Trauma was the most common cause of instability, occurring in 56 patients (46.7%). Ninety patients (75%) were treated with screw/rod constructs; wiring was used in 30 patients (25%)., The median number of fixated segments was 5 (O-C4). Structural bone grafts were implanted in most patients (83.3%). Pre-operative neurological deficits were present in 83 patients (69.2%). Overall neurological improvement was 90.9%. Mean follow-up was 16.1 months (range 4-107 months). There was radiographic evidence of fusion in all patients (100%). One patients suffered neurological deterioration and none died during the first year after surgery. The overall complication rate was 10.8%, including 3 patients with vertebral artery injuries and 2 patients with hardware failures which required surgical correction.

Conclusions: OC fixation is a durable treatment option with acceptable morbidity for patients with OC instability.

Patient Care: Internal occipitocervical fixation has good clinical outcomes in patients with instability. Complication rates allow for detailed preoperative surgical-risk assessment and decision making.

Learning Objectives: The authors review the causes of occipitocervical instability, discuss the indications for surgical intervention, and evaluate long-term surgical outcomes after occipitocervical fixation.

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