目的:坐姿是一种常见的负重姿势,就像站着,但对于腰椎融合术后的坐位矢状面定位仍缺乏足够的认识。本研究旨在探讨固定脊柱从站立到坐姿的适应性及其对未融合节段的影响。
方法:纳入62例腰椎融合术患者(试验组)和40例健康志愿者(对照组)。所有受试者均以站立和坐姿进行了整个脊柱的横向X光片。脊柱骨盆参数包括矢状垂直轴(SVA),T1骨盆角(TPA),腰椎前凸(LL),胸椎后凸(TK),测量骨盆倾斜(PT)。比较两组患者两种体位参数的变化,根据融合水平将患者分为不同的组,并比较其参数。
结果:当从站立姿势变为坐姿时,在患者组和对照组中观察到向前移动的SVA和TPA,伴随着LL的减少,TK和PT的增加,但患者的TPA变化较小,LL,和TK(6.5°±7.2°vs9.7°±6.0°,7.7°±8.3°vs13.6°±8.5°,2.2°±6.5°vs5.4°±5.1°,分别,p<0.05)。腰骶部固定组PT升高低于对照组(4.4°±9.1°vs8.3°±7.1°,p<0.05)。相邻节段变性(ASD)的患者在未融合的腰椎节段中表现出比其他患者更多的后凸畸形(16.4°±10.7°vs-1.0°±4.8°,p<0.05)从站立到坐着。
结论:脊柱在腰椎和胸椎曲线中伸直,结合向前移动轴和骨盆后向改变坐姿时。然而,这些变化在腰椎融合术后的患者中相对有限,因此,相邻的未融合腰椎节段在坐位时可以补偿压力,这可能与ASD有关。
OBJECTIVE: Sitting is a common weight-bearing posture, like standing, but there still lacks enough understanding of sagittal alignment in
sitting position for patients after lumbar fusion. This study aimed to investigate the accommodation of fixed spine from standing to
sitting position and its influence on unfused segments.
METHODS: Sixty-two patients after lumbar fusion (test group) and 40 healthy volunteers (control group) were recruited in this research. All subjects underwent lateral radiographs of entire spine in the standing and
sitting positions. The spinopelvic parameters including sagittal vertical axis (SVA), T1 pelvic angle (TPA), lumbar lordosis (LL), thoracic kyphosis (TK), and pelvic tilt (PT) were measured. The changes in parameters of patients between two positions were compared with control group, and patients were divided in different groups based on fusion level and their parameters were compared.
RESULTS: When changing from standing to
sitting positions, a forward-moving SVA and TPA were observed in both patients and control groups, accompanied by the decrease in LL, TK and increase in PT, but the changes of patients were smaller in TPA, LL, and TK (6.5° ± 7.2° vs 9.7° ± 6.0°, 7.7° ± 8.3° vs 13.6° ± 8.5°, 2.2° ± 6.5° vs 5.4° ± 5.1°, respectively, p < 0.05). Increase of PT in the lumbosacral fixation group was lower than that in the control group (4.4° ± 9.1° vs 8.3° ± 7.1°, p < 0.05). Patients who had adjacent segments degeneration (ASD) showed more kyphosis in unfused lumbar segments than the other patients (16.4° ± 10.7° vs -1.0° ± 4.8°, p < 0.05) from standing to sitting.
CONCLUSIONS: The spine straightens in lumbar and thoracic curve, combined with forward-moving axis and pelvic retroversion when changing to the sitting position. However, these changes are relatively limited in patients after lumbar fusion, so the adjacent unfused lumbar segments compensate to stress during sitting and this may be related to ASD.