Application of the hemi-semi-laminectomy approach in the microsurgical treatment of C2 schwannomas.

STUDY DESIGN

Retrospective analysis of 9 cases of C2 schwannomas who were treated microsurgically with hemi-semi-laminectomy approach.

OBJECTIVE

To review the clinical data and describe several operative nuances and pearls from our experience about the hemi-semi-laminectomy approach that provided successful resection of C2 schwannomas.

SUMMARY OF BACKGROUND DATA

Compared with hemi-laminectomy, the hemi-semi-laminectomy is a more minimally invasive approach for excising spinal neurinomas, which can preserve as much of the mechanically relevant bone structures and facet joints as possible. There are no previous reports about the resection of C2 schwannomas with the hemi-semi-laminectomy approach.

METHODS

Between June 2006 and February 2011, a consecutive series of 9 patients underwent surgery for C2 schwannomas. All patients were treated microsurgically with a midline posterior hemi-semi-laminectomy approach. Data regarding age, sex, duration and type of symptoms, topographical locations, and surgical results were investigated retrospectively.

RESULTS

Of the 9 C2 schwannomas, 8 were located both intradurally and extradurally (dumbbell shaped), and 1 was located extradurally. The initial symptom was numbness of the extremity in 7 patients, neck pain in 1 patient, and clumsiness of the upper extremity in 1 patient. The average duration from initial symptom to surgery was 7.9 months. The average follow-up time was 39.6 months. There were no major surgical complications and tumor recurrence during the follow-up period. Remarkable neurological recovery was observed in 9 patients.

CONCLUSIONS

The hemi-semi-laminectomy is a more minimally invasive approach that can preserve as much of the mechanically relevant bone structures as possible, so that the integrity of the arch of the atlas and the lamina of C2 can be maintained. This approach can provide sufficient field for the resection of the C2 schwannomas that do not extend to the ventral side of the vertebral artery in the anterolateral direction. The minimally invasive access and the remarkable results associated with this approach make it a valid alternative in selected cases.