The requirement of occipital condyle resection in far-lateral approach to anterior foramen magnum lesions

Objective: To determine whether drilling out the occipital condyle facilitates surgery via the far-lateral approach, we compare 10 clinical cases with studies from 8 cadaver heads. Methods: In the last 6 years, 10 patients have been operated on via the far-lateral approach to the foramen magnum. Six of these patients had anterior foramen magnum meningiomas, 1 had a dermoid cyst, 1 had rheumatoid disease of the craniocervical junction, and 2 suffered vertebral artery aneurysms. The approach consisted of retromastoid craniectomy and Cl laminectomy. The increase in the area of exposure that is gained by fractional removal of the occipital condyle was quantified by measuring the degrees of visibility on 8 cadaveric specimens. Results: The 7 tumors and pannus of rheumatoid disease were completely excised and the 2 aneurysms were clipped without drilling of the occipital condyle. No patients had complications associated with surgery. All had improved neurological function postoperatively. In the cadavers, removing one-third of the occipital condyle produced a mean increase of 15.9° visibility, and removing one-half produced a mean increase of 19.9°. Conclusion: We suggest that removal of the occipital condyle is not necessary for the safe and complete resection of anterior intradural foramen magnum tumors.