Comparison of Postoperative Pain and Surgical Outcomes Between Three Types of Modified Muscle-Sparing Laminoplasty and Conventional Laminoplasty for Multilevel Degenerative Cervical Myelopathy

Study Design Retrospective cohort study.Objective This study aimed to compare postoperative pain and surgical outcomes of open-door laminoplasty (LP) and three types of muscle-sparing laminoplasties, namely unilateral muscle-preservation laminoplasty (UL), spinous process splitting double-door laminoplasty (DL) and intermuscular "raising roof" laminoplasty (RL) for multilevel degenerative cervical myelopathy (MDCM).Methods Consecutive MDCM patients underwent LP or modified laminoplasties (UL, DL, RL) in 2022 were enrolled. Patients' preoperative baseline data and surgical characteristics were collected. Postoperative transient pain (TP), the axial pain and Japanese Orthopedic Association (JOA) score and neck disability index (NDI) at 6-month and 12-month follow-up were documented.Results A total of 154 MDCM patients were included and a 12-month follow-up was completed for 148 patients (LP: 36, UL:39, DL: 37, RL:36). No significant difference was observed in the baseline data. Four groups presented favorable and comparable surgical outcome. The RL group reported significantly the least severe TP on the first three days following surgery. However, no significant difference was found in the axial pain and axial symptoms at both follow-ups. After regression analysis, RL group exhibited significantly better efficacy in alleviating Day-1 TP (P = 0.047) and 6-month axial pain (P = 0.040). However, this superiority was not observed at 12-month follow-up.Conclusion All the three muscle-sparing laminoplasty procedures showed similar short-term surgical outcomes compared to LP. The RL procedure demonstrated superiority in alleviating TP and 6-month axial pain compared to LP. The RL and DL groups showed less C5 palsy compared to LP.