Engineering Center for Orthopedic Research (E-CORE), Departments of Bioengineering and Orthopedic Surgery, University of Toledo, Toledo, Ohio, USA.
Department of Orthopedic Surgery, Yamaguchi University Graduate School of Medicine, Ube City, Yamaguchi Prefecture, Japan.
World Neurosurg. 2023 Aug;176:e32-e39. doi: 10.1016/j.wneu.2023.03.057. Epub 2023 Mar 17.
Spinopelvic parameters are vital components that must be considered when treating patients with spinal disease. Several finite element (FE) studies have explored spinopelvic parameters such as sacral slope (SS) and the impact on the lumbar spine, although no study has examined the effect on the hip and sacroiliac joint (SIJ) on varying SS angles. Therefore, it is necessary to have a biomechanical understanding of the impact on the spinopelvic complex.
An FE lumbar, pelvis, and femur model was created from computed tomography scans of a 55-year-old female patient with no abnormalities. Three models were created: a normal model (SS = 26°), a model with high SS (SS = 30°), and a model with low SS (SS = 20°). These models underwent loading for flexion, extension, lateral bending, and axial rotation. Range of motion (ROM), intradiscal pressures, hip joint, and SIJ contact stresses were analyzed.
The high SS model (SS = 30°) indicated the highest ROM in the L5-S1 (slip angle) level and the highest intradiscal pressures. The highest average hip and SIJ contact stresses were present in this model, although the low SS model (SS = 20°) in extension had the largest stresses for the hip and SIJ.
The results provide evidence that patients with higher SS may be more prone to increased ROM at the slip angle (L5-S1). In addition, patients with higher SS were shown to have higher contact stresses on the hip joint and SIJ, potentially leading to SIJ dysfunction. Clinically, correcting lumbar lordosis including SS is important; however, a high SS may have a negative impact on the intervertebral disc, SIJ, and hip joint.
脊柱骨盆参数是治疗脊柱疾病患者时必须考虑的重要组成部分。已有几项有限元（FE）研究探讨了骶骨倾斜角（SS）等脊柱骨盆参数及其对腰椎的影响，但尚无研究探讨不同 SS 角度对髋关节和骶髂关节（SIJ）的影响。因此，有必要从生物力学角度了解对脊柱骨盆复合体的影响。
使用一位 55 岁无异常女性患者的 CT 扫描创建了 FE 腰椎、骨盆和股骨模型。创建了三种模型：正常模型（SS=26°）、高 SS 模型（SS=30°）和低 SS 模型（SS=20°）。这些模型接受了屈伸、侧屈和轴向旋转加载。分析了活动范围（ROM）、椎间盘内压力、髋关节和 SIJ 接触应力。
高 SS 模型（SS=30°）在 L5-S1（滑脱角）水平显示出最高的 ROM 和最高的椎间盘内压力。该模型的髋关节和 SIJ 接触应力平均值最高，尽管低 SS 模型（SS=20°）在伸展时有髋关节和 SIJ 的最大应力。
结果表明，SS 较高的患者可能更容易在滑脱角（L5-S1）处出现 ROM 增加。此外，SS 较高的患者髋关节和 SIJ 的接触应力更高，可能导致 SIJ 功能障碍。临床上，纠正腰椎前凸包括 SS 很重要；然而，高 SS 可能对椎间盘、SIJ 和髋关节产生负面影响。
