All surgical operations were performed by the same group of senior spine surgeons. The range of open door decompression involved C3 ~ C7. For convenient operation and more accurate statistics, the right side of the door axis and the left side of the door seam were selected for all operations. Centerpiece titanium plates were used for intraoperative fixation.

Before surgery, according to the imaging results, according to the effective imaging indicators screened in the early stage and the calculated door opening Angle formula, the door opening Angle of the patient's posterior cervical vertebra and the size of the fitted arch titanium plate were designed by mimics 10.0 software, and the titanium plate was printed using 3D printing technology. During the operation, the developed laminae opener was used to accurately control the door opening Angle and appropriate size titanium plate was installed for internal fixation. The standardized laminae door opening guide was used to complete the preparation of the door shaft side and door opening side of the lamina

All indexes were collected from the patients with Centerpiece titanium plate for internal fixation.

Japanese Orthopedic Association (JOA) score is used to assess the function of spinal cord which is in the form of questionnaires. Postoperative improvement rate = ((postoperative score - preoperative score)/ (17- preoperative score)) X100%. Improvement rate can also correspond to the commonly used efficacy criteria: cure when the improvement rate is 100%, effective when the improvement rate is greater than 60%, effective when 25-60%, and ineffective when less than 25%.

Neck Disability Index (NDI) score is used to assess the disorder of spinal cord which is in the form of questionnaires. Postoperative improvement rate = (total score)/ (numbers of program X5) X100%. Improvement rate can also correspond to the commonly used efficacy criteria: the improvement rate when 60%-80% means extremely severe dysfunction, when 40%-60% means severe dysfunction, when 20-40% means moderate dysfunction, and when less than 20% means mild dysfunction.

A Visual Analogue Scale (VAS) is used to measure the amount of pain that a patient feels ranges across a continuum from none to an extreme amount of pain. Using a ruler, the score is determined by measuring the distance (mm) on the 10cm line between the "no pain" anchor and the patient's mark, providing a range of scores from 0-100. A higher score indicates greater pain intensity.

This index was measured by MRI, which was the ratio of the diameter of the cervical pulp at the most compressed segment to the mean diameter of the cervical pulp at the upper and lower segments without compression.