骨盆倾斜(PT)用作骨盆版本的指标,该值增加表明逆行和残疾。仅将PT用作绝对数值的概念可能会产生误导,尤其是骨盆发生率(PI)值接近正常上限和下限的患者。相对骨盆版本(RPV)是基于PI的个性化测量骨盆版本。相对骨盆版本表示骨盆相对于由PI大小定义的理想骶骨斜率的个性化空间取向。
本研究的目的是比较RPV和PT预测机械并发症的能力及其与健康相关生活质量(HRQoL)评分的相关性。
对前瞻性收集的成人脊柱畸形患者资料进行回顾性分析。机械并发症(近端交界后凸或近端交界衰竭,远端交界后凸或远端交界衰竭,杆断裂,和植入物相关并发症)和HRQoL评分(Oswestry残疾指数[ODI],核心成果计量指数[COMI],简表36物理组件摘要[SF-36PCS],和脊柱侧弯研究学会22脊柱畸形问卷[SRS-22])用作结局指标。
纳入标准为≥4级融合,≥2年随访。PT之间的相关性,RPV,PI,和HRQoL采用Pearson相关系数进行分析。使用单向方差分析比较每个PT类别的RPV亚组的骨盆发生率和机械并发症发生率,学生t检验,和卡方检验。使用二项逻辑回归分析RPV和PT机械并发症的预测模型。
共有222名患者(168名女性,54名男性)符合入选标准。平均年龄为52.2±19.3(18-84)岁。平均随访28.8±8.2(24~62)个月。PT和PI之间存在显著相关性(r=0.613,p<.001),威胁使用PT来量化不同PI值的骨盆版本。相对骨盆版与PI无相关性(r=-0.108,p>.05),能够量化所有PI值的骨盆版本。与PT相比,RPV与ODI有较强的偏相关,COMI,SF-36PCS,和SRS-22得分(p<0.05)。按曲线下面积评估的歧视表现,分类中的百分比准确度,真阳性率,真负率,RPV模型的阳性和阴性预测值优于PT模型。对于平均PI大小,RPV和PT之间的协议是中等的(0.609,p<.001),而小PI和大PI尺寸的一致性较差(分别为0.189,p>.05;-0.098,p>.496)。当通过RPV分析时,每个PT\"0,\"\"+,“和“++”类别进一步分为两个或三个具有不同PI值的患者亚组(分别为p=.000,p=.000和p=.029)。相同PT类别内的相对骨盆版本亚组显示不同的机械并发症发生率(分别为p=.000,p=.020和p=.019)。
当与先前报告的基于人群的20和30度的平均阈值一起用作绝对数值时,骨盆倾斜在量化PI值的整个频谱的Normalmoversion时可能不足或误导。相对骨盆版本提供了一个个性化的量化前,normo-,和所有PI尺寸的逆行。发现施瓦布PT组构成具有不同平均PI值和机械并发症发生率的患者的不均匀亚组。与PT相比,RPV显示与机械并发症和HRQoL的相关性更大。
Pelvic tilt (PT) is used as an indicator of pelvic version with increased values indicating retroversion and disability. The concept of using PT solely as an absolute numerical value can be misleading, especially for the patients with pelvic incidence (PI) values near the upper and lower normal limits. Relative pelvic version (RPV) is a PI-based individualized measure of the pelvic version. Relative pelvic version indicates the individualized spatial orientation of the pelvis relative to the ideal sacral slope as defined by the magnitude of PI.
The aim of this study was to compare RPV and PT for their ability to predict mechanical complications and their correlations with health-related quality of Life (HRQoL) scores.
A retrospective analysis of a prospectively collected data of adult spinal deformity patients was carried out. Mechanical complications (proximal junctional kyphosis or proximal junctional failure, distal junctional kyphosis or distal junctional failure, rod breakage, and implant-related complications) and HRQoL scores (Oswestry Disability Index [ODI], Core Outcome Measures Index [COMI], Short Form-36 Physical Component Summary [SF-36 PCS], and Scoliosis Research Society 22 Spinal Deformity Questionnaire [SRS-22]) were used as outcome measures.
Inclusion criteria were ≥4 levels fusion, and ≥2-year follow-up. Correlations between PT, RPV, PI, and HRQoL were analyzed using Pearson correlation coefficient. Pelvic incidence values and mechanical complication rates in RPV subgroups for each PT category were compared using one-way analysis of variance, Student t test, and chi-squared tests. Predictive models for mechanical complications with RPV and PT were analyzed using binomial logistic regressions.
A total of 222 patients (168 women, 54 men) met the inclusion criteria. Mean age was 52.2±19.3 (18-84) years. Mean follow-up was 28.8±8.2 (24-62) months. There was a significant correlation between PT and PI (r=0.613, p<.001), threatening the use of PT to quantify pelvic version for different PI values. Relative pelvic version was not correlated with PI (r=-0.108, p>.05), being able to quantify pelvic version for all PI values. Compared with PT, RPV had stronger partial correlations with ODI, COMI, SF-36 PCS, and SRS-22 scores (p<.05). Discrimination performance assessed by area under the curve, percentage accuracy in classification, true positive rate, true negative rate, and positive and negative predictive values was better for the model with RPV than for PT. For average PI sizes, the agreement between RPV and PT were moderate (0.609, p<.001), whereas the agreement in small and large PI sizes were poor (0.189, p>.05; -0.098, p>.496, respectively). When analyzed by RPV, each PT \"0,\" \"+,\" and \"++\" category was further divided into two or three distinct subgroups of patients having different PI values (p=.000, p=.000, and p=.029, respectively). Relative pelvic version subgroups within the same PT category displayed different mechanical complication rates (p=.000, p=.020, and p=.019, respectively).
Pelvic tilt may be insufficient or misleading in quantifying normoversion for the whole spectrum of PI values when used as an absolute numeric value in conjunction with previously reported population-based average thresholds of 20 and 30 degrees. Relative pelvic version offers an individualized quantification of ante-, normo-, and retroversion for all PI sizes. Schwab PT groups were found to constitute inhomogeneous subgroup of patients with different mean PI values and mechanical complication rates. Compared with PT, RPV showed a greater association with both mechanical complications and HRQoL.