Department of Neurosurgery, APEX Medical Center, Şişli, Istanbul, Turkey.
Department of Neurosurgery, Faculty of Medicine, Harran University, Şanlıurfa, Turkey.
Eur Spine J. 2024 May;33(5):1821-1829. doi: 10.1007/s00586-024-08220-x. Epub 2024 Mar 30.
Transitional lumbosacral vertebrae (TLSV) are a congenital anomaly of the lumbosacral region that is characterized by the presence of a vertebra with morphological properties of both the lumbar and sacral vertebrae, with a prevalence of up to 36% in asymptomatic patients and 20% in adolescent idiopathic scoliosis patients. In patients with TLSV, because of these morphological changes and the different numbers of lumbar vertebrae, there are two optional reference sacral endplates that can be selected intently or inadvertently to measure the spinopelvic parameters: upper and lower endplates. The spinopelvic parameters measured using the upper and lower endplates are significantly different from each other as well as from the normative values. Therefore, the selection of a reference endplate changes the spinopelvic parameters, lumbar lordosis (LL), and surgical goals, which can result in surgical over- or under-correction. Because there is no consensus on the selection of sacral endplate among these patients, it is unclear as to which of these parameters should be used in diagnosis or surgical planning. The present study describes a standardization method for measuring the spinopelvic parameters and LL in patients with TLSV.
Upper and lower endplate spinopelvic parameters (i.e., pelvic incidence [PI], sacral slope [SS], and pelvic tilt) and LL of 108 patients with TLSV were measured by computed tomography. In addition, these parameters were measured for randomly selected subjects without TLSV. The PI value in the TLSV group, which was closer to the mean PI value of the control group, was accepted as valid and then used to create an optimum PI (OPI) group. Finally, the spinopelvic parameters and LL of the OPI and control groups were compared.
Except for SS, all spinopelvic parameters and LL were comparable between the OPI and control groups. In the OPI group, 60% of the patients showed valid upper endplate parameters, and 40% showed valid lower endplate parameters. No difference was noted in the frequency of valid upper or lower endplates between the sacralization and lumbarization groups. Both the OPI and control groups showed nearly comparable correlations between their individual spinopelvic parameters and LL, except for PI and LL in the former.
Because PI is unique for every individual, the endplate whose PI value is closer to the normative value should be selected as the reference sacral endplate in patients with TLSV.
过渡腰骶椎（TLSV）是腰骶部的一种先天性异常，其特征是存在具有腰椎和骶椎形态特征的椎体，在无症状患者中的患病率高达 36%，在青少年特发性脊柱侧凸患者中的患病率为 20%。在 TLSV 患者中，由于这些形态变化和腰椎数量的不同，有两个可选的参考骶骨终板可供选择，以专注或不经意地测量脊柱骨盆参数：上终板和下终板。使用上终板和下终板测量的脊柱骨盆参数彼此之间以及与正常值之间存在显著差异。因此，参考终板的选择会改变脊柱骨盆参数、腰椎前凸（LL）和手术目标，从而导致手术过度或矫正不足。由于这些患者之间没有关于骶骨终板选择的共识，因此不清楚在诊断或手术计划中应使用哪些参数。本研究描述了一种用于测量 TLSV 患者脊柱骨盆参数和 LL 的标准化方法。
通过计算机断层扫描测量 108 例 TLSV 患者的上终板和下终板脊柱骨盆参数（即骨盆入射角[PI]、骶骨倾斜角[SS]和骨盆倾斜角）和 LL。此外，还对无 TLSV 的随机选择的受试者进行了这些参数的测量。TLSV 组中更接近对照组平均 PI 值的 PI 值被接受为有效，并随后用于创建最佳 PI（OPI）组。最后，比较了 OPI 组和对照组的脊柱骨盆参数和 LL。
除 SS 外，OPI 组和对照组的所有脊柱骨盆参数和 LL 均无差异。在 OPI 组中，60%的患者表现出有效的上终板参数，40%的患者表现出有效的下终板参数。腰骶化和腰椎化组之间，有效上终板或下终板的频率无差异。除前者的 PI 和 LL 外，OPI 组和对照组的个体脊柱骨盆参数和 LL 之间的相关性几乎相似。
由于 PI 对每个人都是独一无二的，因此应选择与 TLSV 患者的参考骶骨终板更接近正常值的终板作为参考骶骨终板。
