Comparison of fusion effectiveness between anterior cervical uncovertebral joint fusion and conventional interbody fusion: a prospective, randomized, controlled trial study

English Keywords:Cervical spondylosis  Anterior cervical discectomy and fusion  Uncovertebral joint fusion  Fusion rate  Randomized controlled trial

English Abstract:

  【Abstract】 Objectives: To compare the fusion rate and safety effectiveness of uncovertebral joint fusion(UJF) and traditional interbody fusion(TIF) in anterior cervical discectomy and fusion(ACDF). Methods: 44 patients with single level cervical spondylosis were recruited and treated from May 2020 to June 2021. The patients were divided into study group and control group using computerized random number list method with 22 cases in each group. The study group was treated with UJF and the control group was treated with TIF. Autologous iliac bone was taken for bone grafting in both groups. The early postoperative(3 and 6 months after operation) fusion rates of the two groups were evaluated by dynamic X-ray and CT. The clinical outcomes were evaluated by the Japanese Orthopaedic Association(JOA) score, neck disability index(NDI), and visual analogue scale(VAS) score. Results: A total of 40 patients completed the planned follow-up including 20 cases in the study group and 20 cases in the control group. There were no statistical differences in age, gender, and BMI between the two groups of patients. And there were no significant differences in operative time(133.0±29.4min vs. 124.2±26.3min, P=0.3271) and intraoperative bleeding(68.5±48.7ml vs. 83.5±54.5ml, P=0.3645) between the two groups. The fusion rate in UJF group was significantly higher than that in TIF group at 3 and 6 months after operation(3 months: 70% vs. 10%, P<0.0001; 6 months: 95% vs. 65%, P=0.0177). The JOA, VAS and NDI scores of the two groups at one week, three months and six months after operation were significantly improved compared with those before operation. However, there was no significant difference between the two groups at any follow-up time(P>0.05). There were no adverse results such as prosthesis subsidence, displacement, screw loosening, fracture, and restenosis of intervertebral foramen in each group. Conclusions: Both UJF and TIF can obtain satisfactory outcomes in treating single level cervical spondylosis. UJF features significantly higher early fusion rate than TIF, which is a safe and effective surgical method.