Department of Orthopedic Surgery, Limb Lengthening and Deformity Service, Hospital for Special Surgery, Affiliated with Weill Medical College of Cornell University, 535 East 70th Street, New York, NY 10021, USA.
Clin Orthop Relat Res. 2011 Jan;469(1):244-50. doi: 10.1007/s11999-010-1460-z. Epub 2010 Jul 13.
The picture archiving and communication system (PACS) eventually will replace the use of standard hard-copy radiographs. It is unknown whether measurements of limb length discrepancy (LLD) and deformity on PACS compare in accuracy and reproducibility with those from hard-copy radiographs.
QUESTIONS/PURPOSES: We compared the reproducibility and reliability of LLD and deformity measurements for each of these two media.
We retrospectively reviewed 51-inch standing lower extremity images obtained for LLD or deformity analysis from 40 patients to compare the measurements and their reliability on hard-copy film with those performed on soft-copy PACS. Two observers independently performed measurements twice using each system at 1-week intervals to minimize interobserver or intraobserver bias. Intraclass correlation coefficients (ICCs) were determined to test intraobserver and interrater reliability of Rater 1 and Rater 2.
Interrater reliability of measurements made on hard copy ranged from 0.69 to 0.99 and PACS-derived measurements ranged from 0.66 to 0.98. Intraobserver reliability for Rater 1 for measurements made on hard copy ranged from 0.853 to 0.999 and PACS-derived measurements ranged from 0.80 to 0.996. Intraobserver reliability for Rater 2 for measurements made on hard copy ranged from 0.931 to 0.999 and PACS-derived measurements ranged from 0.962 to 0.999.
Each system yielded comparable reliability for measurements, therefore, transition to PACS to perform measurements in patients with LLD or deformity can be made with confidence.
Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.
影像归档和通信系统（PACS）最终将取代标准硬拷贝射线照片的使用。目前尚不清楚 PACS 上的肢体长度差异（LLD）和畸形测量在准确性和可重复性方面是否与硬拷贝射线照片相媲美。
问题/目的：我们比较了这两种介质的 LLD 和畸形测量的可重复性和可靠性。
我们回顾性地分析了 40 例患者的 51 英寸站立下肢图像，以比较硬拷贝胶片上和软拷贝 PACS 上的测量值及其可靠性。两位观察者在 1 周的间隔内，使用每种系统分别进行两次独立测量，以最小化观察者间或观察者内的偏倚。使用组内相关系数（ICC）来测试 Rater 1 和 Rater 2 的观察者内和观察者间可靠性。
硬拷贝上的测量值的观察者间可靠性范围为 0.69 至 0.99，而 PACS 衍生的测量值的观察者间可靠性范围为 0.66 至 0.98。Rater 1 在硬拷贝上进行测量时的观察者内可靠性范围为 0.853 至 0.999，而 PACS 衍生的测量值的观察者内可靠性范围为 0.80 至 0.996。Rater 2 在硬拷贝上进行测量时的观察者内可靠性范围为 0.931 至 0.999，而 PACS 衍生的测量值的观察者内可靠性范围为 0.962 至 0.999。
每个系统的测量值都具有相当的可靠性，因此，可以有信心地向 PACS 过渡以进行 LLD 或畸形患者的测量。
III 级，诊断研究。有关证据水平的完整描述，请参见作者指南。
