Park Jin-Sung, Kang Dong-Ho, Lee Chong-Suh, Park Se-Jun
Department of Orthopedic Surgery, Spine Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Department of Orthopedic Surgery, Haeundae Bumin Hospital, Busan, South Korea.
Spine (Phila Pa 1976). 2025 Sep 4. doi: 10.1097/BRS.0000000000005489.
Retrospective study using prospectively collected data.
To investigate the impact of the lordosis distribution index (LDI) on proximal junctional kyphosis (PJK) and clinical outcomes in patients with degenerative flatback syndrome (DFS).
Proper lumbar lordosis (LL) correction is essential for successful outcomes in corrective surgery for DFS. However, the clinical significance of LDI remains debatable, likely due to the lack of a clear definition regarding normal LDI.
Patients with DFS who underwent fusion from the low thoracic spine (T9-T12) to the pelvis with ≥2 years of follow-up were included. LDI correction status was categorized as undercorrection, matched correction, and overcorrection based on pelvic incidence (PI)-adjusted normative LDI values. The impact of LDI correction on PJK development and clinical outcomes was evaluated using logistic regression analysis, both with and without age-adjusted PI-LL correction status.
A total of 222 patients were included in the study (female, 89.6%; mean age, 69.6 y; mean fusion length, 7.7). PJK developed in 69 patients (31.1%) during a mean follow-up of 45.1 months. Logistic regression analysis revealed that LDI alone did not affect PJK development, but when combined with overcorrection of age-adjusted PI-LL (vs. matched correction; odds ratio [OR]=2.255, P<0.001), LDI overcorrection (vs. matched correction; OR=1.784, P=0.030) significantly increased the risk of PJK. Clinical outcomes were not influenced by the LDI correction status but were significantly affected by age-adjusted PI-LL correction status.
LDI correction alone did not affect PJK occurrence, but in conjunction with age-adjusted PI-LL overcorrection, LDI overcorrection significantly increased the risk of PJK. Clinical outcomes were affected by age-adjusted PI-LL correction with best outcomes in matched correction group but not by the LDI correction status. This lack of association between LDI and clinical outcomes may be attributable to the fact that LDI alone did not have a significant effect on determining spinopelvic alignment.
使用前瞻性收集的数据进行回顾性研究。
探讨腰椎前凸分布指数（LDI）对退行性平背综合征（DFS）患者近端交界性后凸（PJK）及临床疗效的影响。
适当的腰椎前凸（LL）矫正对于DFS矫正手术的成功结局至关重要。然而，LDI的临床意义仍存在争议，这可能是由于缺乏关于正常LDI的明确定义。
纳入接受从胸9至胸12椎体至骨盆融合术且随访时间≥2年的DFS患者。根据骨盆入射角（PI）调整后的正常LDI值，将LDI矫正状态分为矫正不足、匹配矫正和矫正过度。使用逻辑回归分析评估LDI矫正对PJK发生及临床疗效的影响，分析时分别纳入和未纳入年龄调整后的PI-LL矫正状态。
本研究共纳入222例患者（女性占89.6%；平均年龄69.6岁；平均融合长度7.7）。在平均45.1个月的随访期内，69例患者（31.1%）发生了PJK。逻辑回归分析显示，单独的LDI并不影响PJK的发生，但与年龄调整后的PI-LL过度矫正（与匹配矫正相比；优势比[OR]=2.255，P<0.001）相结合时，LDI过度矫正（与匹配矫正相比；OR=1.784，P=0.030）会显著增加PJK的风险。临床疗效不受LDI矫正状态的影响，但受年龄调整后的PI-LL矫正状态的显著影响。
单独的LDI矫正并不影响PJK的发生，但与年龄调整后的PI-LL过度矫正相结合时，LDI过度矫正会显著增加PJK的风险。临床疗效受年龄调整后的PI-LL矫正影响，匹配矫正组疗效最佳，而不受LDI矫正状态的影响。LDI与临床疗效之间缺乏相关性可能是由于单独的LDI对确定脊柱骨盆对线没有显著影响。
