Sports Orthopedic Research Center - Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital Amager-Hvidovre, Denmark; Physical Medicine & Rehabilitation Research-Copenhagen (PMR-C), Department of Physical and Occupational Therapy, Copenhagen University Hospital Amager-Hvidovre, Denmark.
Physical Medicine & Rehabilitation Research-Copenhagen (PMR-C), Department of Physical and Occupational Therapy, Copenhagen University Hospital Amager-Hvidovre, Denmark; Department of Orthopaedic Surgery, Copenhagen University Hospital Amager-Hvidovre, Denmark.
Foot Ankle Surg. 2021 Aug;27(6):655-659. doi: 10.1016/j.fas.2020.08.004. Epub 2020 Aug 25.
Elongation of the Achilles tendon after rupture is a frequent complication. The Achilles Tendon Length Measure (ATLM) and the Achilles Tendon Resting Angle (ATRA) are indirect length measures using the resting angle of the ankle. Copenhagen Achilles Length Measure (CALM) is a direct ultrasound measure. The purpose of this study was to examine the construct validity of ATLM and ATRA using CALM as gold standard.
As the three measurements measure slightly different constructs and have different scales a direct comparison was not possible. Instead a mixed linear regression model was performed investigating the three models: CALM-ATRA, CALMATLM and ATRA-ATLM.
130 patients were available for analysis. All three regression models demonstrated a statistically significant (p < 0.01) linear relationship and acceptable certainty of the estimates.
ATRA and ATLM were found to have acceptable construct validity when using CALM as gold standard for assessing tendon elongation after an Achilles tendon rupture.
跟腱断裂后延长是一种常见的并发症。跟腱长度测量（ATLM）和跟腱静息角度（ATRA）是使用踝关节静息角度的间接长度测量方法。哥本哈根跟腱长度测量（CALM）是一种直接的超声测量方法。本研究旨在使用 CALM 作为金标准来检验 ATLM 和 ATRA 的结构效度。
由于这三种测量方法测量的是略有不同的结构，且具有不同的尺度，因此无法直接进行比较。相反，进行了混合线性回归模型分析，研究了三种模型：CALM-ATRA、CALMATLM 和 ATRA-ATLM。
130 名患者可用于分析。所有三种回归模型均显示出具有统计学意义的（p < 0.01）线性关系和可接受的估计确定性。
当使用 CALM 作为评估跟腱断裂后跟腱延长的金标准时，发现 ATRA 和 ATLM 具有可接受的结构效度。
