Double Dome Laminoplasty: A Novel Technique for C2 Decompression.

Objective: To introduce a new surgical technique - double dome laminoplasty for decompression of the entire C2 lamina and preservation of an extensor muscle insertion.

Methods: Eleven consecutive cervical myelopathy patients due to ossification of the posterior longitudinal ligament involving the Axis (C2) area were contained at this study. Direct decompression was evaluated as an increasing rate in space available cord (%) and posterior cord shift (mm) at C2 level. The Japanese Orthopaedic Association (JOA) score, visual analogue scale, and C2-7 Cobb angle in a neutral lateral x-ray were analyzed.

Results: The mean increase in space available for spinal cord at the C2 level, average posterior cord shift, and JOA recovery rate were 69.7%, 5.3 ± 0.15 mm, and 58.0%, respectively. Cervical lordotic angle was maintained in all patients. One patient reported neck pain (visual analogue scale 6) postoperatively. No specific complications such as C2 laminar fracture or insufficient decompression were observed.

Conclusion: We recommend double dome laminoplasty for treating patients with cervical myelopathy involving the C2 area to avoid C2 laminectomy, reduce postoperative neck pain, and maintain lordotic cervical spine alignment.