SAGITTAL BALANCE AFTER POSTERIOR INSTRUMENTATION IN LUMBAR FRACTURES

ABSTRACT Objective: When a lumbar fractures developes a significant deformity, the sagittal balance is altered which can lead to clinical consequences. The aim of this study was to measure and analyze the sagittal balance in patients with lumbar fractures operated with posterior instrumentation after three months and analyze their correlation with the different variables of the patient and the fracture. Methods: Sixty-three medical records of patients with lumbar fracture operated with posterior instrumentation were analyzed, excluding those with previous spinal pathology, or inability to stand upright. The parameters of pelvic incidence, sacral slope, pelvic tilt, lumbar lordosis, lumbar lordosis/pelvic incidence (LL/ PI) ratio, as well as the pre and postoperative status of segmental kyphosis and residual pain were measured. Results: Eighteen women, 44 men, with mean age of 42 years, with lumbar fractures: 29 in L1, 19 in L2, 10 in L3, 3 in L4 and 1 in L5. AOSpine Clasification: 2 type A1, 2 type A2, 37 type A3, 19 type A4, 2 type B. All patients were operated with a transpedicular polyaxial system. More than 80% of patients with spinopelvic balance within parameters considered normal. More than 70% with lumbar lordosis and LL/PI ratio within parameters. All with improvement of segmental kyphosis (average correction of 8.5°, p

摘要 研究目的：当腰椎骨折出现明显畸形时，可引发矢状位平衡（sagittal balance）改变，进而导致临床不良结局。本研究旨在测量并分析后路内固定术后3个月的腰椎骨折患者的矢状位平衡情况，并分析其与患者及骨折相关变量的相关性。
研究方法：本研究纳入63例行后路内固定术的腰椎骨折患者的病历资料进行分析，排除既往存在脊柱病变或无法直立的患者。测量并记录了骨盆入射角（pelvic incidence, PI）、骶骨倾斜角（sacral slope）、骨盆倾斜角（pelvic tilt）、腰椎前凸角（lumbar lordosis）、腰椎前凸角/骨盆入射角（LL/PI）比值，以及节段性后凸畸形术前与术后状态和残余疼痛情况。
研究结果：本研究纳入患者中，女性18例、男性44例，平均年龄42岁；腰椎骨折部位分布为：L1节段29例、L2节段19例、L3节段10例、L4节段3例、L5节段1例。AOSpine分型：A1型2例、A2型2例、A3型37例、A4型19例、B型2例。所有患者均采用经椎弓根多轴内固定系统进行手术治疗。超过80%的患者脊柱骨盆平衡参数处于正常参考范围内；超过70%的患者腰椎前凸角及LL/PI比值处于正常参考范围内。所有患者的节段性后凸畸形均得到改善（平均矫正角度为8.5°，p）