Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, NO. 37 GuoXue Road, 610041, Chengdu, Sichuan, China.
BMC Musculoskelet Disord. 2021 Feb 15;22(1):185. doi: 10.1186/s12891-021-04052-8.
The purpose of the study was to investigate whether pelvic incidence (PI) will affect the occurrence of PJK in Lenke 5 AIS patients after correction surgery and try to explore a better surgical scheme based on PI.
Lenke 5C AIS patients that underwent correction surgery with a minimum of a 2-year follow-up were identified. Demographic and radiographic data were collected preoperatively, postoperatively, and at the final follow-up. The comparison between the PJK and the Non-PJK group was conducted and the subgroup analysis was performed based on the preoperative value of PI to investigate the potential mechanism of PJK. Clinical assessments were performed using the Scoliosis Research Society (SRS)-22 questionnaire.
The mean preoperative Cobb angle of the TL/L curve was 53.4°±8.6. At the final follow-up, the mean TL/L Cobb angle was drastically decreased to 7.3°±6.8 (P < 0.001). The incidence of PJK in Lenke 5 AIS was 18.6 %, 21.9 % (7/32) in the low PI group (PI < 45°) and 15.8 % (6/38) in the high PI group (PI ≥ 45°), and there was no statistical difference between the two groups (χ = 0.425, P = 0.514). For low PI patients, there is no significant difference where the UIV is located with regards to the TK apex between the PJK and Non-PJK subgroups (χ = 1.103, P = 0.401). For high PI patients, PJK was more likely to occur when UIV was cephalad to than caudal to the TK apex (31.25 % vs. 4.7 %, P = 0.038). There was no significant difference in the selection of LIV between the two groups.
There is no difference in the incidence of PJK between the Lenke 5 AIS patients with low PI (< 45°) and high PI (≥45°), but the main risk factor of PJK should be different. For patients with low PI, overcorrection of LL should be strictly avoided during surgery. For patients with high PI, the selection of UIV should not be at or cephalad to the apex of thoracic kyphosis to retain more mobile thoracic segments.
本研究旨在探讨骨盆入射角（PI）是否会影响 Lenke 5 型 AIS 患者矫正术后发生后凸进展（PJK）的情况，并尝试基于 PI 探讨更好的手术方案。
本研究纳入了接受矫正手术且随访时间至少 2 年的 Lenke 5C AIS 患者。收集患者术前、术后和末次随访时的人口统计学和影像学资料。对 PJK 组和非 PJK 组进行比较，并根据术前 PI 值进行亚组分析，以探讨 PJK 的潜在机制。采用脊柱侧凸研究协会（SRS）-22 问卷进行临床评估。
TL/L 曲线术前 Cobb 角的平均值为 53.4°±8.6。末次随访时，TL/L Cobb 角明显减小至 7.3°±6.8（P<0.001）。Lenke 5 AIS 患者中 PJK 的发生率为 18.6%（7/32），低 PI 组（PI<45°）为 21.9%（7/32），高 PI 组（PI≥45°）为 15.8%（6/38），两组间无统计学差异（χ=0.425，P=0.514）。对于低 PI 患者，PJK 组和非 PJK 组中 UIV 位于 TK 顶点上方或下方时，UIV 与 TK 顶点的距离无显著差异（χ=1.103，P=0.401）。对于高 PI 患者，UIV 位于 TK 顶点上方时更易发生 PJK（31.25%比 4.7%，P=0.038）。两组间 LIV 的选择无显著差异。
低 PI（<45°）和高 PI（≥45°）Lenke 5 AIS 患者的 PJK 发生率无差异，但 PJK 的主要危险因素可能不同。对于低 PI 患者，术中应严格避免 LL 过度矫正。对于高 PI 患者，UIV 的选择不应位于或位于胸椎后凸顶点上方，以保留更多活动度的胸椎节段。
