Efficacy of open-door laminoplasty for cervical hyperextension injury accompanied with or without spinal cord-canal mismatch / 中华创伤杂志

ABSTRACT

Objective:To explore the clinical efficacy of open-door laminoplasty in treatment of cervical spinal hyperextension injury accompanied with or without spinal cord-canal mismatch.Methods:A retrospective case-control study was performed to analyze the clinical data of 42 patients with cervical spine hyperextension in Shanghai Ninth People’s Hospital，Shanghai Jiaotong University School of Medicine from January 2016 to June 2019. There were 31 males and 11 females at age range of 40-78 years［（59.7 ± 9.9）years］. All patients underwent open-door laminoplasty.Preoperative Japanese Orthopaedic Association score（JOA）was（10.2 ± 3.8）points，and American Spinal Injury Association（ASIA）spinal cord injury score was（260.4 ± 47.5）points. Those with spinal cord occupation rate（SCOR）equal to or more than 70% were classified as spinal cord-canal mismatched group（n=21），and those with SCOR less than 70% were classified as spinal cord-canal matched group（n=21）. ASIA total score，ASIA upper and lower limb motor scores，ASIA sensory score，JOA score，surgical improvement rates and complications were compared between the two groups before operation，at postoperative one week and at the latest follow-up.Results:All patients were followed up for 12-26 months［（19.1 ± 2.3）months］. Both groups had significantly improved ASIA total score at postoperative one week and at the latest follow-up，compared with that before operation（ P < 0.05）. The two groups showed no significant difference in ASIA total score at postoperative one week（ P > 0.05）. ASIA total score in unmatched group was（307.6 ± 9.9）points at the latest follow-up，significantly lower than that in matched group［（315.4 ± 8.7）points］（ P < 0.01）. ASIA upper limb motor score in mismatched group was（29.1 ± 7.0）points and（36.6 ± 6.5）points at postoperative one week and at the latest follow-up，significantly lower than that in matched group［（42.0 ± 5.7）points，（47.4 ± 2.5）points］（ P < 0.01），while there was no significant difference in ASIA lower limb motor score and sensory score between the two groups（ P > 0.05）. Both groups showed significantly improved JOA score at postoperative one week and at the latest follow-up，compared with that before operation（ P < 0.05）. JOA score in mismatched group was（11.5 ± 3.0）points and（12.5 ± 3.0）points at postoperative one week and at the latest follow-up，significantly lower than that in matched group［（13.5 ± 2.4）points，（15.0 ± 2.0）points］（ P < 0.01）. Postoperative improvement rate in matched group was 95%（20/21），and was 85%（18/21）in mismatched group（ P < 0.05）. Cervical axial pain occurred in 3 patients in each group and C 5 nerve root palsy in 2 patients in matched group，all of which were relieved after conservative treatment. No implant loosening or breakage occurred during follow-up. Conclusions:Open-door laminoplasty can improve part of the nerve function of patients with cervical hyperextension injury. However，the overall improvement degree of nerve function especially recovery of upper limb motor function in patients with spinal cord-canal mismatch is inferior to those in spinal cord-canal matched patients.