Department of Orthopedic Surgery, Columbia University Medical Center, The Och Spine Hospital at New York Presbyterian, New York, NY.
Department of Orthopaedic Surgery, Washington University, St. Louis, MO.
Spine (Phila Pa 1976). 2022 Oct 1;47(19):1372-1381. doi: 10.1097/BRS.0000000000004413. Epub 2022 Jul 1.
Multicenter Cohort.
Assess normative values of sagittal spinal and lower extremity alignment in asymptomatic volunteers stratified by age and gender.
Our understanding of ideal sagittal alignment is still evolving. The Multiethnic Alignment Normative Study (MEANS) investigated skeletal alignment of the largest multiethnic cohort of asymptomatic adult volunteers. We aim to assess normative values of sagittal spinal and lower extremity alignment in asymptomatic volunteers stratified by age and gender.
Asymptomatic volunteers between the ages of 18-80 years were enrolled prospectively and then analyzed retrospectively from six different centers. Volunteers included reported no significant neck or back pain, nor any known spinal disorder(s). All volunteers underwent a standing full-body or full-spine low-dose stereoradiograph.
MEANS consisted of 468 volunteers with a mean age of 40.4±14.8 years. Thoracic kyphosis (TK) from T4 to T12 showed a mean of 37.4±10.9°. The average L1-S1 lumbar lordosis (LL) was -57.4±11.3°. LL did not show significant differences across the five age groups. TK showed a significant difference based on age ( P <0.0001). Sagittal vertical axis increased across age groups from -14.2 mm in young adults to 17.0 mm in patients >64. Similar trend was seen for T1 pelvic angle with a mean of 5.0° in young adults and 13.7° in those older than age 64. Knee flexion increased across age groups without a significant change in odontoid-knee distance which is a surrogate for the center of the head aligned over the knees.
In asymptomatic volunteers, sagittal alignment parameters showed a slow and steady change across age groups exemplified by an increase in TK. However, LL did not show a significant decrease across age groups. Volunteers used compensatory mechanisms such as slight pelvis retroversion, knee flexion, and neck extension to maintain an aligned sagittal posture with their head centered over their knees (odontoid-knee).
多中心队列研究。
评估按年龄和性别分层的无症状志愿者的矢状脊柱和下肢对线的正常值。
我们对理想矢状位对线的理解仍在不断发展。多民族排列正常研究（MEANS）调查了最大的多民族无症状成年志愿者队列的骨骼排列。我们旨在评估按年龄和性别分层的无症状志愿者的矢状脊柱和下肢对线的正常值。
18-80 岁的无症状志愿者被前瞻性招募，然后从六个不同的中心进行回顾性分析。志愿者报告没有明显的颈部或背部疼痛，也没有任何已知的脊柱疾病。所有志愿者均接受站立全身或全脊柱低剂量立体射线照相检查。
MEANS 包括 468 名平均年龄为 40.4±14.8 岁的志愿者。T4 到 T12 的胸椎后凸（TK）平均值为 37.4±10.9°。平均 L1-S1 腰椎前凸（LL）为-57.4±11.3°。五个年龄组之间的 LL 没有显著差异。TK 根据年龄存在显著差异（P<0.0001）。SVA 随着年龄组的增加从年轻人的-14.2mm 增加到>64 岁患者的 17.0mm。在年轻人中平均为 5.0°，在年龄大于 64 岁的人中为 13.7°，T1 骨盆角也呈现出相似的趋势。随着年龄组的增加，膝关节屈曲增加，而齿状突-膝关节距离没有明显变化，这是头部中心与膝关节对齐的替代指标。
在无症状志愿者中，矢状位对线参数随着年龄组的增加而缓慢稳定地变化，表现为 TK 的增加。然而，LL 在各年龄组之间没有明显下降。志愿者使用代偿机制，如轻微的骨盆后旋、膝关节屈曲和颈部伸展，以保持头部位于膝关节中心的对齐矢状位姿势（齿状突-膝关节）。
3 级。
