Fig. 1

a Exposure of the C1-C7 posterior arch and lamina. The spinous arch is removed, and grooves are made at the junction of the lamina and lateral mass. b The door-oriented cortical bone of the inner plate was retained. When performing C1 laminoplasty, a slot was made between the posterior arch and lateral mass. c Excision of the ligamentum flavum, adhesive dura mater and vascular bridge was performed to achieve an appropriate opening angle and adequate decompression of the spinal cord. d Titanium miniplates are placed to secure the elevated laminae. An I-type mini-titanium plate was used in C1 laminoplasty, and a T-type mini-titanium plate was applied in C2-C7 laminoplasty