The comparison of two different surgical methods in clinical efficacy for unstable Hangman′s fractures

English Keywords:Hangman′s fractures  Combined anterior and posterior surgery  Posterior surgery  Efficacy  Cervical sagittal balance

English Abstract:

  【Abstract】 Objectives: To compare the clinical outcomes between posterior C2/3 fixation and fusion (PFF) and anteroposterior surgery [combined anterior cervical discectomy and fusion (ACDF) and posterior compressive C2 pedicle screw fixation] for unstable Hangman′s fractures. Methods: A total of 34 patients with unstable Hangman′s fractures who underwent two different surgeries from March 2010 to August 2017 were retrospectively reviewed. 20 cases were treated with PFF(group P), and 14 cases were treated with anteroposterior surgery(group AP). Clinical data as American Spinal Injury Association(ASIA) scale, visual analogue scale (VAS), neck disability index(NDI) and Odom criteria were recorded before surgery and at the final follow-up. Radiographic parameters related to cervical sagittal balance as occiput-C2 angel, C2/3 Cobb angle, cervical lordosis(CL) and C2-C7 sagittal vertical axis(cSVA) were also recorded on admission, before surgery and at final follow-up. All clinical and radiological data were compared between the two groups. Results: At final follow-up, all patients had significant improvement in neck pain and neck mobility. The operation time(group P vs group AP; 105.7±13.8min vs 177.9±14.7min) had significant difference(P＜0.05). 3 patients in group P and 2 in group AP recovered from grade D to grade E. At final follow-up, both groups showed significant VAS and NDI scores compared to those before surgery(P＜0.001); and there was no significant difference of the scores between preoperation and final follow-up in the two groups(P＞0.05); and there was no significant difference of the changes of VAS and NDI between preoperation and final follow-up in the two groups(P＞0.05). Numbers of patients evaluated their level of satisfaction as good or excellent were 17 in group P(the satisfactory rate was 85.0%) and 13 in group AP(the satisfactory rate was 92.9%), and there was no statistical difference between the two groups(P＞0.05). There was no statistical difference of occiput-C2 angel, C2/3 Cobb angle, CL and cSVA(P＞0.05). A statistically significant decrease of occiput-C2 angel and cSVA was found between preoperation and final follow-up, and C2/3 Cobb angle and CL increased(P＜0.001). The changes of radiological parameters between preoperation and final follow-up were more significant statistically in group AP(P＜0.05). Conclusions: Both PFF and combined ACDF and posterior compressive C2 pedicle screw fixation can achieve satisfactory clinical efficacy for unstable Hangman′s fractures. Furthermore, anteroposterior surgery has an advantage in maintaining cervical sagittal balance.