Karkenny Alexa J, Magee Lacey C, Landrum Matthew R, Anari Jason B, Spiegel David, Baldwin Keith
Division of Pediatric Orthopaedics, Children's Hospital at Montefiore, Bronx, New York.
Division of Orthopaedics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
JB JS Open Access. 2021 Mar 10;6(1). doi: 10.2106/JBJS.OA.20.00143. eCollection 2021 Jan-Mar.
Pelvic obliquity (PO), or pelvic alignment in the coronal plane, is an important radiographic parameter to indicate fusion levels and judge success of scoliosis correction in patients with neuromuscular scoliosis. There are multiple commonly used techniques to measure PO that have good to excellent interrater and intrarater reliability, but these different methods yield inconsistent values when used on the same radiograph. This study evaluates the inconsistency in the magnitude of PO measurements for patients with neuromuscular scoliosis among 5 common measurement techniques.
Radiographs of 63 patients with neuromuscular scoliosis were evaluated by 5 raters. Each rater measured PO on each radiograph using the Osebold, O'Brien, Allen and Ferguson, Lindseth, and Maloney techniques. Patients were divided into 2 cohorts based on coronal balance or imbalance. Interrater and intrarater analyses were performed using a 2-way random effects model to calculate absolute agreement. The mean difference in PO between all possible pairs of the techniques was compared using a 2-tailed t test.
The Maloney and Osebold techniques demonstrated excellent interrater reliability, and the Maloney, Osebold, and O'Brien techniques demonstrated excellent intrarater reliability. Significant differences in PO measurement were found in 6 of the 10 comparisons for the balanced spines and 8 of the 10 comparisons for the unbalanced spines. Variability in measurement was captured by best-fit lines, which demonstrated greater dispersion between the means for the Osebold and Maloney techniques in the unbalanced spines than in the balanced spines.
To our knowledge, this study is the first to evaluate mean differences in magnitude of PO among common measurement techniques while accounting for coronal imbalance. Although there is no gold standard for measuring PO, the Maloney and Osebold techniques are the most consistent. This study suggests that those 2 techniques can be used interchangeably when the spine is coronally balanced, but the Osebold technique becomes more inconsistent than the Maloney technique when coronal imbalance exceeds 2 cm.
This information is relevant to surgeons using PO to plan fusion levels and striving for objective ways to judge correction intraoperatively as well as for researchers compiling PO data from multiple centers or studies.
骨盆倾斜度（PO），即冠状面内的骨盆排列，是用于指示神经肌肉型脊柱侧弯患者融合节段并判断脊柱侧弯矫正效果的一项重要影像学参数。有多种常用的测量PO的技术，其测量者间和测量者内信度良好至优秀，但在同一X线片上使用这些不同方法时会得出不一致的值。本研究评估了5种常见测量技术在测量神经肌肉型脊柱侧弯患者PO大小时的不一致性。
63例神经肌肉型脊柱侧弯患者的X线片由5名测量者进行评估。每位测量者使用奥泽博尔德（Osebold）、奥布赖恩（O'Brien）、艾伦和弗格森（Allen and Ferguson）、林塞思（Lindseth）以及马洛尼（Maloney）技术在每张X线片上测量PO。患者根据冠状面平衡或失衡分为2组。使用双向随机效应模型进行测量者间和测量者内分析以计算绝对一致性。使用双侧t检验比较所有可能的技术对之间PO的平均差异。
马洛尼和奥泽博尔德技术显示出优秀的测量者间信度，马洛尼、奥泽博尔德和奥布赖恩技术显示出优秀的测量者内信度。在平衡脊柱的10组比较中有6组以及失衡脊柱的10组比较中有8组发现PO测量存在显著差异。测量的变异性通过最佳拟合线体现，结果表明，在失衡脊柱中奥泽博尔德和马洛尼技术的均值之间的离散度大于平衡脊柱中的离散度。
据我们所知，本研究首次在考虑冠状面失衡的情况下评估了常见测量技术在PO大小方面的平均差异。虽然测量PO尚无金标准，但马洛尼和奥泽博尔德技术最为一致。本研究表明，当脊柱冠状面平衡时，这两种技术可互换使用，但当冠状面失衡超过2 cm时，奥泽博尔德技术比马洛尼技术更不一致。
该信息对于使用PO来规划融合节段并力求在术中进行客观矫正判断的外科医生，以及从多个中心或研究中汇总PO数据的研究人员而言具有相关性。
