Odland Kari, Yson Sharon, Polly David W
The Department of Orthopedic Surgery, University of Minnesota, 2450 Riverside Avenue South, Suite R200, Minneapolis, MN, 55454, USA.
Spine Deform. 2023 May;11(3):559-566. doi: 10.1007/s43390-023-00649-2. Epub 2023 Feb 3.
Studies on sagittal alignment parameters have solely focused on patients with preexisting spinal deformity. Limited data in the literature have analyzed pelvic incidence (PI) values in an asymptomatic patient population. The purpose of this study was to: (1) systematically review the literature to analyze normative PI values in asymptomatic patients; and (2) provide a more definitive geometric measurement guide for determining surgical interventions.
A systematic review of retrospective studies was performed by searching PubMed to identify studies that analyzed PI measurements in asymptomatic subjects. The following search phrases were used: (pelvic incidence, pelvic tilt, sacral slope, sagittal alignment, radiograph, asymptomatic, normative values, and adults) using Boolean operators AND, OR and NOT. Patients with pathology involving the osseous pelvic anatomy (including fracture, infection, tumor, previous surgery, and lumbosacral fusion) that would prevent measurement of the selected parameters were not included. Pelvic incidence (PI) values were analyzed.
A total of 29 studies met inclusion criteria, including 3629 asymptomatic subjects who underwent standing lateral radiographs (mean age, 41.1 years; range, 24-69 years) for the purposes of analyzing pelvic incidence values. Overall, the mean PI value was 50.0° (range, 24-69) which is consistent with reported values in the literature.
Wide anatomical variability and broad clinical interpretation of PI normative values do little to guide surgical planning for successful outcomes. However, this systematic review has presented PI-stratified normative values in a large sample of asymptomatic subjects which can serve as a grounded geometric reference for spine surgeons when considering surgical intervention approaches.
矢状面排列参数的研究仅聚焦于已有脊柱畸形的患者。文献中关于无症状人群骨盆入射角（PI）值的分析数据有限。本研究的目的是：（1）系统回顾文献，分析无症状患者的正常PI值；（2）为确定手术干预提供更明确的几何测量指南。
通过检索PubMed对回顾性研究进行系统回顾，以确定分析无症状受试者PI测量值的研究。使用了以下检索词：（骨盆入射角、骨盆倾斜、骶骨斜率、矢状面排列、X线片、无症状、正常数值、成年人），使用布尔运算符AND、OR和NOT。涉及骨盆骨性解剖结构病变（包括骨折、感染、肿瘤、既往手术和腰骶融合）而无法测量所选参数的患者未纳入。分析骨盆入射角（PI）值。
共有29项研究符合纳入标准，包括3629例无症状受试者，他们接受了站立位侧位X线片检查（平均年龄41.1岁；范围24 - 69岁）以分析骨盆入射角值。总体而言，平均PI值为50.0°（范围24 - 69），这与文献报道的值一致。
PI正常数值存在广泛的解剖学变异性和宽泛的临床解读，对指导手术规划以获得成功结果作用不大。然而，本系统回顾呈现了大量无症状受试者按PI分层的正常数值，可为脊柱外科医生在考虑手术干预方法时提供有依据的几何参考。
