退变性脊柱畸形患者经第2骶椎骶髂螺钉骨盆固定术中与术后骨盆入射角的变化

Intraoperative and postoperative changes of pelvic incidence in patients with degenerative spinal deformity treated with S2 alar-iliac screw fixation

中文关键词:  退变性脊柱畸形  骨盆固定  脊柱矫形  骨盆入射角  骶髂关节  第2骶椎骶髂螺钉

英文关键词:Degenerative spinal deformity  Pelvic fixation  Spinal correction  Pelvic incidence  Sacroiliac joint  S2 alar-illac screw

中文摘要:

  【摘要】 目的：探讨退变性脊柱畸形患者经第2骶椎骶髂（S2 alar-iliac，S2AI）螺钉骨盆固定术中与术后骨盆入射角（pelvic incidence，PI）的变化。方法：回顾性分析2016年11月～2020年10月期间在我院接受后路矫形长节段融合固定术治疗的退变性脊柱畸形患者，其中22例患者采用双侧S2AI螺钉固定至骨盆，男性3例，女性19例；年龄45~74岁（62.3±7.9岁）。术中使用计算机辅助下O型臂X线机导航系统引导螺钉置入。收集患者术前、术后1周及末次随访时站立位全脊柱正侧位X线片，测量冠状面侧凸Cobb角、PI、腰椎前凸角（lumbar lordosis，LL）、PI与LL差值（PI-LL）、骨盆倾斜角（pelvic tilt，PT）、骶骨倾斜角（sacral slope，SS）、矢状面平衡（sagittal vertical axis，SVA）；导出术中俯卧位下O型臂X线机导航系统扫描的患者骨盆矢状面图像，并测量PI、PT、SS。结果：22例患者内固定节段数为5~17个（11.1±2.21个），随访5~13个月（6.64±1.43个月）。术前、术后1周和末次随访时冠状面侧凸Cobb角分别为38.04°±21.12°、19.16°±12.49°、19.01°±11.99°，LL分别为28.48°±28.12°、40.61°±15.25°、39.25°±15.51°，SVA分别75.64±64.66mm、21.82±19.42mm、23.18±19.12mm，PI分别为55.55°±14.68°、50.47°±13.35°、53.94°±13.37°，PI-LL分别为27.10°±22.00°、9.86°±10.41°、12.92°±13.02°，PT分别为31.55°±10.25°、19.69°±7.7°、24.25°±8.28°，SS分别为24.00°±16.61°、30.78°±10.27°、29.55°±11.23°。术后1周和末次随访时的侧凸Cobb角、LL、SVA、PI、PI-LL、PT和SS与术前比较均有显著性差异（P<0.05）；末次随访时的PI和PT与术后1周比较有显著性差异（P<0.05）。术中PI、PT、SS分别为45.17°±14.20°、21.56°±6.71°、23.61°±12.86°，PT和PI与术前、术后1周及末次随时比较均有显著性差异（P<0.05），SS与术前比较无显著性差异（P>0.05），与术后1周及末次随访时比较有显著性差异（P<0.05）。其中21例（95%）患者术中PI与术前比较减少大于5°，13例（59%）患者术后站立位PI较术前下降大于5°。结论：应用S2AI螺钉进行骨盆固定的退变性脊柱畸形患者术中俯卧位下PI较术前站立位PI显著性降低，术后站立位PI较术中回升，但仍较术前站立位降低。

英文摘要:

  【Abstract】 Objectives: To investigate the changes of pelvic incidence(PI) during and after S2 alar-iliac(S2AI) screw fixation in patients with degenerative spinal deformity. Methods: Patients with degenerative spinal deformity who received posterior long segment fusion and fixation in our hospital from November 2016 to October 2020 were retrospectively analyzed. Among them, 22 patients underwent bilateral S2AI screw fixation distal to pelvis, including 3 males and 19 females, aged 45-74 years(62.3±7.9 years). Computer-assisted O-arm navigation system was used to guide screw placement. The full-length standing anteroposterior and lateral X-ray images before operation, 1 week after, and at the final follow-up were collected, and Cobb angle, PI, lumbar lordosis(LL), value of PI-LL, pelvic tilt(PT), sacral slope(SS), sagittal vertical axis(SVA) were measured at each time point. The sagittal images of pelvis of patients in the prone position scanned by O-arm navigation system during operation were exported, and the values of PI, PT, and SS were measured. Results: The number of fixed segments in 22 patients was 5-17(11.1±2.21), and the follow-up period was 5-13 months(6.64±1.43 months). At preoperation, postoperation and final follow-up, the values of imaging parameters were respectively, the Cobb angles: 38.04°±21.12°, 19.16°±12.49°, and 19.01°±11.99°; LL: 28.48°±28.12°, 40.61°±15.25°, and 39.25°±15.51°; SVA: 75.64±64.66mm, 21.82±19.42mm, 23.18±19.12mm; PI: 5.55°±14.68°, 50.47°±13.35°, and 53.94°±13.37°; PI-LL: 27.10°±22.00°, 9.86°±10.41°, and 12.92°±13.02°; PT: 31.55°±10.25°, 19.69°±7.7°, and 24.25°±8.28°; SS: 24.00°±16.61°, 30.78°±10.27°, and 29.55°±11.23°. The Cobb angle, LL, SVA, PI, PI-LL, PT and SS at postoperative 1 week and the last follow-up were significantly different from those before operation(P<0.05), and the PI and PT at the last follow-up were with significant differences from those at 1 week after operation(P<0.05). The intraoperative PI, PT and SS were 45.17°±14.20°, 21.56°±6.71°, and 23.61°±12.86°, respectively, of which, PI and PT were significantly different from those at preoperation, 1 week after operation and the final follow-up(P<0.05), while intraoperative SS was not statistically different from that before operation(P>0.05), yet it was with significant difference from postoperative 1 week and the last follow-up(P<0.05). In 21 patients(95%) the intraoperative PI decreased by more than 5° compared with that before operation, and in 13 patients(59%) the postoperative PI in standing position decreased by more than 5° compared with the preoperative PI. Conclusions: Patients with degenerative spinal deformity treated with S2AI screws had a significant decrease in intraoperative PI in prone position comparing with preoperative PI in standing position, and the postoperative PI in standing position was smaller than the preoperative PI in standing position although it was bigger than the intraoperative PI.