[Contrastive analysis of neck axial symptoms after hybrid surgery or traditional anterior cervical discectomy and fusion for treatment of two-level cervical disease].

OBJECTIVE:To explore the occurrence condition of the neck axial symptom (AS) after cervical Bryan artificial disc replacement combined with anterior cervical discectomy and fusion (hybrid surgery) and traditional anterior cervical discectomy and fusion (ACDF surgery) to treat the two-level cervical disease, and to do contrastive analysis. METHODS:Between August 2006 and March 2010, 18 patients underwent hybrid surgery (group A) and 30 patients underwent two-level ACDF surgery (group B). There was no significant difference in age, gender, disease duration, type, and operated segment between 2 groups (P > 0.05). The Japanese Orthopaedic Association (JOA) score, neck disability index (NDI) score, cervical curvature of the operated segment, total range of motion (ROM) of C(2-7), ROM of the adjacent segment, and incidence of neck AS were recorded and compared between before operation and at last follow-up. Results All the patients were followed up 18-34 months (24.1 months on average). In both groups, the JOA and NDI scores at last follow-up had significantly improvement when compared with preoperative scores (P < 0.01), but there was no significant difference between 2 groups at preoperation and last follow-up (P > 0.05). The kyphosis incidence of the operated segment in group B was significantly higher than that in group A (chi2 = 5.333, P = 0.021). There was no significant difference in the total ROM of C(2-7) between at preoperation and last follow-up in group A (t = 0.410, P = 0.685); the total ROM of C(2-7) at last follow-up was significantly lower than that at preoperation in group B (t = 3.007, P=0.006); and significant difference was found between 2 groups at last follow-up (t = 2.664, P = 0.013). At last follow-up, ROM of the superior and inferior adjacent segments in group B increased obviously (P < 0.05) and was significantly higher than that in group A (t = 2.252, P = 0.033; t = -2.203, P = 0.037). The incidence of neck AS were 16.7% in group A and 46.7% in group B, showing significant difference at last follow-up (chi2 = 4.427, P = 0.035). CONCLUSION:Compared with two-level ACDF surgery, hybrid surgery has good outcomes. At the same time, it can maintain the curvature of operated segments and total ROM, avoid excessive increased ROM of the adjacent segments, and reduce the incidence of neck AS.