Schroeder Nicholas, Noschenko Andriy, Burger Evalina, Patel Vikas, Cain Christopher, Ou-Yang David, Kleck Christopher
Department of Orthopedics, University of Colorado Anschutz Medical Campus, 12631 E. 17th Ave., Mail Stop B202, Aurora, CO 80045, USA.
Department of Orthopedics, University of Colorado Anschutz Medical Campus, 12631 E. 17th Ave., Mail Stop B202, Aurora, CO 80045, USA.
Spine Deform. 2018 Nov-Dec;6(6):753-761. doi: 10.1016/j.jspd.2018.03.008.
Retrospective single-center.
To investigate changes in pelvic incidence from flexion to extension. To assess interobserver error in the measurement of pelvic incidence.
Pelvic incidence (PI) has been considered a static parameter since it was originally described. But recent studies have shown that PI can change with age and after spinal procedures. Changes in PI based on position have not been investigated.
Seventy-two patients who had obtained flexion and extension radiographs of the lumbar spine were identified using strict inclusion and exclusion criteria. PI along with pelvic tilt (PT), sacral slope (SS), and lumbar lordosis were measured in both flexion and extension by two independent measurers. Variations in all parameters and interobserver measurement reliability were analyzed for the entire group.
PI changed significantly from flexion to extension with a general tendency to decrease: mean (-0.94°), p <.044. However, these changes might have had opposite vectors, and exceeded | 6°| (measurement error) in 20% of cases, with a maximum of 12°. Inconsistencies in changes of SS, as opposed to PT from flexion to extension, were found to be the major factor determining changes in PI (p >.001). Obesity significantly contributed to differences in PI between flexion and extension (p = .003).
PI is a dynamic parameter that changes between flexion and extension. Changes in SS are the main factor involved in these changes, implicating movement through the sacroiliac joints as the cause. Obese patients have greater changes in PI from flexion to extension.
Level II.
回顾性单中心研究。
研究从屈曲位到伸展位时骨盆入射角的变化。评估骨盆入射角测量中的观察者间误差。
自骨盆入射角（PI）最初被描述以来，一直被视为一个静态参数。但最近的研究表明，PI会随年龄和脊柱手术后发生变化。基于体位的PI变化尚未得到研究。
采用严格的纳入和排除标准，确定72例获得腰椎屈曲和伸展位X线片的患者。由两名独立测量者在屈曲位和伸展位测量PI以及骨盆倾斜度（PT）、骶骨倾斜度（SS）和腰椎前凸。分析了整个组中所有参数的变化和观察者间测量的可靠性。
PI从屈曲位到伸展位有显著变化，总体呈下降趋势：平均值为（-0.94°），p <.044。然而，这些变化可能具有相反的向量，并且在20%的病例中超过了| 6°|（测量误差），最大值为12°。发现与从屈曲位到伸展位的PT相反，SS变化的不一致是决定PI变化的主要因素（p >.001）。肥胖显著导致了屈曲位和伸展位之间PI的差异（p =.003）。
PI是一个动态参数，在屈曲位和伸展位之间会发生变化。SS的变化是这些变化的主要因素，这意味着通过骶髂关节的运动是其原因。肥胖患者从屈曲位到伸展位时PI的变化更大。
二级。
