Axial Neck Pain after Cervical Laminoplasty with Preserving C7 Spinous Process Using C7 Arcocristectomy: A Prospective Study

STUDY DESIGN: Single-blinded, randomized, single-center, prospective study. PURPOSE: This study aims to compare the radiographical and clinical outcomes between C7 laminoplasty and C7 arcocristectomy, which preserves the C7 spinous process. OVERVIEW OF LITERATURE: Laminoplasty is a widely used surgical method that decompresses the cervical spinal cord. However, axial neck pain is one of the major factors of dissatisfaction, and still, it is not clearly solved the reduction method of postoperative axial neck pain. METHODS: Thirty-one patients with multilevel cervical spondylotic myelopathy who required C6–C7 level decompression surgery were operated and followed up for 24 months. One group (15 patients) received C7 arcocristectomy without laminoplasty, and the other group (16 patients) received C7 laminoplasty. Flexion, neutral, and extension angles were measured using the Cobb method at C2–C7 to evaluate preoperative and postoperative radiographic parameters. Range of motion (ROM), ROM preservation rate of the cervical spine, C2–C7 sagittal vertical axis (SVA), and T1 slope were measured using C-spine lateral X-ray. The Visual Analog Scale (VAS) and modified Japanese Orthopedic Association (JOA) score were used to compare preoperative and postoperative clinical symptoms. RESULTS: Flexion, neutral, extension angles of the cervical spine, C2–C7 SVA, T1 slope, ROM, ROM preservation rate, and modified JOA score were not significantly different between the two groups (p>0.05). In the C7 arcocristectomy group, the average postoperative VAS for axial neck pain was increased in 13.3% (2/15) of the patients, whereas in the C7 laminoplasty group, the average postoperative VAS was increased in 43.8% (7/16) of the patients (p=0.018). CONCLUSIONS: C7 arcocristectomy, which preserves the C7 spinous process and posterior structures, is a useful technique for relieving axial neck pain.