Evaluation of the curative effect of anterior cervical discectomy and fusion in treating cervical whiplash injury in patients with spinal canal stenosis

English Keywords:Cervical spinal cord injury  Anterior cervical discectomy and fusion  Cervical intervertebral disc herniation  Whiplash injury  Cervical spinal canal stenosis

English Abstract:

  【Abtract】 Objectives: To investigate the clinical efficacy of anterior cervical discectomy and fusion in treating cervical whiplash injury in patients with cervical spinal canal stenosis caused by cervical disc herniation. Methods: The clinical data of 50 patients with whiplash injury of the cervical spine who were treated in our hospital from January 2010 to December 2018 with anterior cervical discectomy and fusion were retrospectively analyzed. There were 32 males and 18 females, aged 35-75 years(53.6±13.6 years). According to the minimum sagittal diameter of fibrous spinal canal at the target segment in the sagittal position on MRI T2WI before surgery, the patients were divided into stenosis group(minimal sagittal diameter≤13mm, 32 patients) and non-stenosis group(minimal sagittal diameter>13mm, 18 patients). There were no statistical differences in age and gender between the two groups. No significant difference of follow-up was found between the stenosis group(25.6±7.4 months) and non-stenosis group(27.4±8.3 months). The total American Spinal Injury Association(ASIA) score, sensory score, and motor score before operation and at postoperative 1 month and 1 year and final follow-up were recorded; the improvement rate of Japanese Orthopedic Association(JOA) score at postoperative 1 month and 1 year and final follow-up, and surgical improvement rate at final follow-up were calculated; and the occurrence of related complications were recorded. Results: The total ASIA scores at postoperative 1 month, 1 year and final follow-up in the two groups were statistically different from those before operation(P＜0.05), respectively; there were no significant differences between the two groups at preoperation and 1 month after operation(P＞0.05) and there were significant differences between groups at postoperative 1 year and final follow-up(P＜0.05). The ASIA motor scores of the upper extremity at postoperative time points increased significantly than those before operation in both groups respectively(P＜0.05), and there were statistical differences between groups before operation and at postoperative time points(P＜0.05). The ASIA motor scores of the lower extremity at postoperative time points also increased significantly than those before operation in both groups respectively(P＜0.05), while no significant difference was found between groups before operation and at postoperative time points(P＞0.05). The ASIA sensory scores at postoperative time points all increased significantly than those before operation in both groups respectively(P＜0.05), and there were statistical differences between groups before operation and at postoperative time points(P＜0.05). The JOA scores in each group at postoperative time points all improved than those before operation(P＜0.05). The improvement rates of JOA score in stenosis group and non-stenosis group were 37.3% and 55.9% at 1 month after surgery, 61.3% and 73.6% at 1 year after surgery, and 77.3% and 91.1% at final follow-up, with significant differences between groups at different time points(P＜0.05). The surgical improvement rate was 88%(28/32) in the stenosis group and 94%(17/18) in the non-stenosis group at final follow-up, and the difference was statistically significant(P<0.05). Four patients in each group developed axial pain in the neck; 13 patients(stenosis group) and 11 patients(non-stenosis group) developed swallowing pain or swallowing foreign body sensation postoperatively, which improved after symptomatic treatment; One case of prevertebral hematoma and two cases of C5 nerve root palsy in the stenosis group, which improved after symptomatic treatment such as neurotrophic and debulking. During follow-up, no unexpected emergencies such as loosening of internal fixation or falls occurred in either group. Conclusions: Anterior cervical discectomy and fusion can achieve satisfactory outcomes in treating patients with whiplash-like injuries of cervical spine. However, the short-term postoperative outcome is inferior in patients with cervical spinal canal stenosis caused by cervical disc herniation before trauma than those without stenosis.