Lee Ki Young, Lee Jung-Hee, Kang Kyung-Chung, Shin Won-Ju, Im Sang Kyu, Cho Seong Jin
J Neurosurg Spine. 2019 Jul 12;31(5):703-710. doi: 10.3171/2019.4.SPINE1915. Print 2019 Nov 1.
The incidence of proximal junctional kyphosis (PJK) after long-segment fixation in patients with adult spinal deformity (ASD) has been reported to range from 17% to 61.7%. Recent studies have reported using "hybrid" techniques in which semirigid fixation is introduced between the fused and flexible segments at the proximal level to allow a more gradual transition. The authors used these hybrid techniques in a clinical setting and analyzed PJK to evaluate the usefulness of the flexible rod (FR) technique.
The authors retrospectively selected 77 patients with lumbar degenerative kyphosis (LDK) who underwent sagittal correction and long-segment fixation and had follow-up for > 1 year. An FR was used in 30 of the 77 patients. PJK development and spinal sagittal changes were analyzed in the FR and non-FR groups, and the predictive factors of PJK between a PJK group and a non-PJK group were compared.
The patient population comprised 77 patients (75 females and 2 males) with a mean (± SD) follow-up of 32.0 ± 12.7 months (36.7 ± 9.8 months in the non-FR group and 16.8 ± 4.7 months in the FR group) and mean (± SD) age of 71.7 ± 5.1 years. Sagittal balance was well maintained at final follow-up (10.5 and 1.5 mm) in the non-FR and FR groups, respectively. Thoracic kyphosis (TK) and lumbar lordosis (LL) were improved in both groups, without significant differences between the two (p > 0.05). PJK occurred in 28 cases (36.4%) in total, 3 (10%) in the FR and 25 (53.2%) in the non-FR group (p < 0.001). Postoperatively, PJK was observed at an average of 8.9 months in the non-FR group and 1 month in the FR group. No significant differences in the incidence of PJK regarding patient factors or radiological parameters were found between the PJK group and non-PJK group (p > 0.05). However, FR (vs non-FR) and interbody fusion except L5-S1 using oblique lumbar interbody fusion (vs non-oblique lumbar interbody fusion), demonstrated a significantly lower PJK prevalence (p < 0.001 and p = 0.044) among the surgical factors.
PJK was reduced after surgical treatment with the FR in the patients with LDK. Solid long-segment fixation and the use of the FR may become another surgical option for spine surgeons who plan and make decisions regarding spine reconstruction surgery for patients with ASD.
据报道，成人脊柱畸形（ASD）患者在进行长节段固定后近端交界性后凸（PJK）的发生率在17%至61.7%之间。最近的研究报道了使用“混合”技术，即在近端融合节段和灵活节段之间引入半刚性固定，以实现更渐进的过渡。作者在临床环境中使用了这些混合技术，并分析PJK以评估柔性棒（FR）技术的有效性。
作者回顾性选择了77例接受矢状面矫正和长节段固定且随访时间超过1年的腰椎退行性后凸（LDK）患者。77例患者中有30例使用了FR。分析了FR组和非FR组中PJK的发生情况和脊柱矢状面变化，并比较了PJK组和非PJK组之间PJK的预测因素。
患者群体包括77例患者（75例女性和2例男性），平均（±标准差）随访时间为32.0±12.7个月（非FR组为36.7±9.8个月，FR组为16.8±4.7个月），平均（±标准差）年龄为71.7±5.1岁。在末次随访时，非FR组和FR组的矢状面平衡分别保持良好（10.5和1.5 mm）。两组的胸椎后凸（TK）和腰椎前凸（LL）均得到改善，两组之间无显著差异（p>0.05）。总共28例（36.4%）发生PJK，FR组3例（10%），非FR组25例（53.2%）（p<0.001）。术后，非FR组平均在8.9个月时观察到PJK，FR组在1个月时观察到。PJK组和非PJK组在患者因素或放射学参数方面的PJK发生率无显著差异（p>0.05）。然而，在手术因素中，FR（与非FR相比）以及除L5-S1外使用斜外侧腰椎椎间融合术的椎间融合（与非斜外侧腰椎椎间融合术相比）显示出PJK发生率显著较低（p<0.001和p=0.044）。
LDK患者采用FR手术治疗后PJK减少。坚实的长节段固定和FR的使用可能成为脊柱外科医生为ASD患者规划和决策脊柱重建手术时的另一种手术选择。
