Objective: To analyze the relationship between post-operative proximal junctional kyphosis (PJK) and C₂-femoral heads center (C₂-FH), pelvic fixation in adult spinal deformity (ASD) patients, so as to provide a reference for the preoperative decision-making and the postoperative intervention timely. Methods: It was a retrospective study that analyzed 34 cases of ASD patients who underwent posterior pedicle screw fixation in Nanjing Drum Tower Hospital between January 2017 and May 2017. ASD patients were divided into two groups according to fixation options: the sacroiliac fixation group and the non-sacroiliac fixation group. The spine-pelvis parameters were evaluated on full-length X ray films of spine at preoperatively, 2 weeks postoperatively and the last follow-up, and the incidence of PJK was recorded. Results: A total of 34 ASD patients (3 males and 31 females) were included in this study, with an average age of (58±6) years. The mean follow-up period was (2.9±1.0) years (2.0-4.0 years). The age, follow-up time and various spine-pelvis parameters showed no significant differences between the two groups (all P>0.05). The immediate postoperative C₂-FH in the sacroiliac fixation group was significantly lower than that in the non-sacroiliac fixation group [(-69.46±30.85) mm vs (-31.62±15.31) mm, P<0.001]. The incidence of PJK was as high as 50.0% (8/16) in patients with sacroiliac fixation, but it was only 22% (4/18) in patients without sacroiliac fixation (P=0.016). At the last follow-up, the C₂-FH of both groups were both higher than -20 mm (both were approximately -15 mm, P=0.976), indicating that the C₂-FH was compensated in both groups. Due to the loss of the distal compensation ability, the incidence of PJK in the sacroiliac fixation group was higher than that in the non-sacroiliac fixation group. Due to the fixation of pelvis and most of lumbar spine, no significant differences were found in lumbar lordosis (LL), pelvic tilt (PT) and sacral slope (SS) at the last follow-up in both groups when compared with those after the operation (all P>0.05); while the thoracic kyphosis (TK) and cervical lordosis (CL) increased significantly (both P<0.05) to compensate C₂-FH at the last follow-up. Conclusion: It’s demonstrated that C₂-FH< -2 cm and pelvic fixation are high risk factors of PJK in ASD patients. It is suggested that both global sagittal balance and pelvic fixation should be considered in decision-making and corrective surgery, rather than only focusing on spine-pelvic parameters.

目的： 分析成人脊柱畸形（ASD）患者术后近端交界性后凸（PJK）与颈2-股骨头中心位移（C₂-FH）以及骶髂固定的关系，为ASD患者术前决策和术后治疗提供参考。 方法： 回顾性分析2017年1至5月在南京鼓楼医院行全椎弓根螺钉内固定矫正术的34例成人脊柱畸形患者的病历资料。根据手术远端有无固定至骶骨将纳入的ASD患者分为两组：骶髂固定组（16例）和非骶髂固定组（18例）。分析比较两组术前、术后2周及末次随访时在全脊柱侧位X线片上评估的脊柱骨盆参数，并记录PJK的发生率。 结果： 共纳入ASD患者34例，其中男3例，女31例，年龄（58±6）岁，随访（2.9±1.0）年（2.0~4.0年）。骶髂固定组与非骶髂固定组的年龄、随访时间等一般情况及各项脊柱骨盆参数差异均无统计学意义（均P>0.05）。骶髂固定组术后即刻的C₂-FH小于非骶髂固定组［（-69.46±30.85）mm比（-31.62±15.31）mm，P<0.001］。骶髂固定的患者中半数（8/16）发生PJK，而骶髂未固定组仅有4例（4/18），两组差异有统计学意义（P=0.016）。末次随访时，两组C₂-FH均>-20 mm且均接近于-15 mm（P=0.976），说明两组C₂-FH均发生了代偿。由于骶髂以及大部分腰椎的固定，两组末次随访时腰椎前凸（LL）、骨盆倾斜角（PT）及骶骨倾斜角（SS）与术后即刻差异均无统计学意义（均P>0.05）；为了代偿C₂-FH，末次随访时胸椎后凸（TK）和颈椎前凸（CL）均较术后即刻增加，差异均有统计学意义（均P<0.05）。 结论： C₂-FH<-2 cm和骶髂固定是ASD患者术后发生PJK的高风险因素。建议在决策和矫正手术时应同时考虑整体矢状面的平衡和骶髂固定两方面因素，而非仅关注脊柱骨盆参数。.