Development and reliability of the Achilles Tendon Length Measure and comparison with the Achilles Tendon Resting Angle on patients with an Achilles tendon rupture

摘要

Highlights ? A new indirect measurement of the length of the Achilles tendon after rupture was developed. ? Secondary aim was to quantify changes in the new measurement and the Achilles Tendon Resting Angle. ? Both measurements showed excellent inter-rater reliability. Abstract Background There is a need for a valid, reliable, and easily applicable clinical measure of the length of the Achilles tendon (AT) after rupture. This study examines the reliability of a new ruler based measurement, the Achilles Tendon Length Measure (ATLM) in comparison with the goniometer-based Achilles Tendon Resting Angle (ATRA). Methods Measurements were performed by two independent physiotherapists eight weeks after AT rupture on 28 patients treated non-operatively. Results The mean (SD) injured ATLM was 56.5 (2.3)cm, ICC 2.1 0.91(CI [0.72–0.97]), SEM 0.7cm (SEM% 1.2), MDC 1.9cm (MDC% 3.4). Corresponding data for the injured ATRA was mean 64.4° (3.9°), ICC 2.1 0.84 (CI [0.68–0–92]), SEM 1.5° (SEM% 2.4), MDC 4.3° (MDC% 6.6). Conclusion Both ATLM and ATRA showed excellent inter-rater reliability with low measurement error. Both measurements seem easy to use in clinical practice and potentially providing an indirect measure of the length of the AT after rupture.