Efficacy of three-dimensional guide plate technique guided sacral 2 alar iliac screws fixation in patients with degenerative kyphoscoliosis.

Objective: To investigate the efficacy of three-dimensional (3D) guide plate technique guided sacral 2 alar iliac (S2AI) screws fixation in patients with degenerative kyphoscoliosis.

Methods: Eighty-four patients with degenerative kyphoscoliosis who were admitted to our hospital were selected as the subjects. They were divided into control group and observation group by the random number table method, with 42 patients in each group. S2AI free-hand screw implantation technique was adopted for screws fixation in control group; 3D guide plate technique guided S2AI screw implantation was used for screws fixation in observation group. A 2-year routine follow-up was carried out after the surgery. The followings were compared: screw parameters of preoperative pre-set screw trajectory and postoperative actual screw trajectory: sagittal angle (SA), transverse angle (TA), horizon distance from the entry point to the median sacral crest (HD), vertical distance from the entry point to the superior margin of the second posterior sacral foramina (VD), and the incidence rate of complications; scoliosis Cobb angle, sagittal vertical axis, C7 plumb line-center sacral vertical line (C7PL-CSVL), regional kyphosis Cobb angle (RK), pelvic incidence (PI), and pelvic tilt (PT) before, after and 2 years after surgery; Oswestry disability index (ODI) and shot form 36 health survey questionnaire (SF-36) before and 2 years after surgery.

Results: The difference between preoperative simulation and postoperative actual values of SA, TA, HD and VD was significantly lower in observation group than in control group (P<0.001). Scoliosis Cobb angle, lumbar lordosis, C7PL-CSVL, RK, PI and PT after and 2 years after surgery were significantly improved than those before surgery in the two groups (P<0.001), and there was no significant difference between those after surgery and 2 years after surgery (P>0.05). Patients in the two groups had significantly lower ODI scores and higher SF-36 scores at 2 years after surgery than those before surgery (both P<0.001), and there was no significant difference at 2 years after surgery between the two groups (P>0.05). The incidence rate of complications in observation group was significantly smaller than that in control group (P<0.05).

Conclusion: 3D guide plate technique guided S2AI fixation can significantly increase the accuracy of screw implantation, effectively correct degenerative kyphoscoliosis, achieve rigid internal fixation, improve patient's spinal function and quality of life, and greatly enhance surgical safety, which is worthy of clinical popularization.