Tendon loading in runners with Achilles tendinopathy: Relations to pain, structure, and function during return-to-sport

Abstract
We aimed to (1) compare pain, tendon structure, lower limb function, and Achilles tendon loads while running between limbs in runners with Achilles tendinopathy, and (2) explore the relations of pain, tendon structure, and lower limb function to Achilles tendon loads while running. Twenty runners with Achilles tendinopathy participated in this pilot study. Pain was assessed with questionnaires, quantitative sensory testing, and functional testing. Tendon morphology and mechanical properties were evaluated with ultrasound imaging, continuous shear wave elastography, and ultrasound imaging combined with dynamometry. Lower limb function was assessed with an established test battery. Achilles tendon loads were estimated from biomechanical data acquired during running. Compared to the least symptomatic limb, the most symptomatic limb had lower scores on the Victorian Institute of Sports Assessment – Achilles questionnaire and worse pain during drop countermovement jumping, hopping, and running. Tendon thickness and cross-sectional area were greater, and Young's modulus, drop countermovement jump height, and plyometric quotient during hopping were lower on the most symptomatic limb. Side-to-side differences in drop countermovement jump height were significantly associated with side-to-side differences in Achilles tendon peak forces and average loading rates during running. Various measures of pain, structure, and function differ between limbs in runners with Achilles tendinopathy during return-to-sport. Tendon forces, however, do not differ between limbs during comfortable running. In addition to measures that differ between limbs, measures of performance during drop countermovement jumping may aid in clinical decision-making during return-to-sport because they are associated with tendon forces while running.
Description
This is the peer reviewed version of the following article: Corrigan, P, Hornsby, S, Pohlig, RT, Willy, RW, Cortes, DH, Silbernagel, KG. Tendon loading in runners with Achilles tendinopathy: Relations to pain, structure, and function during return-to-sport. Scand J Med Sci Sports. 2022; 00: 1- 12. doi: 10.1111/sms.14178, which has been published in final form at https://doi.org/10.1111/sms.14178. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited. This article will be embargoed until April 30, 2023.
Keywords
biomechanics, mechanical properties, physical performance, running, tendinitis, ultrasonography
Citation
Corrigan, P, Hornsby, S, Pohlig, RT, Willy, RW, Cortes, DH, Silbernagel, KG. Tendon loading in runners with Achilles tendinopathy: Relations to pain, structure, and function during return-to-sport. Scand J Med Sci Sports. 2022; 00: 1- 12. doi: 10.1111/sms.14178