Defining neuromechanical mechanisms of Achilles tendinopathy

PROJECT SUMMARY
Mid-substance Achilles tendinopathy is a painful, debilitating, and chronic tendon pathology. Rehabilitation
exercises are the first treatment option for patients, but clinical studies have reported 20-60% of patients
continue to experience pain and symptoms 5-years later. Despite these poor outcomes, rehabilitation protocols
remain standardized because of insufficient evidence to support precision care. Our Parent R01 project will
determine similarities in tendon loading and biomechanics in patients with mid-substance Achilles tendinopathy
and how these similarities affect tendon healing, pain, and functional outcomes. In this Ancillary R01, we will
leverage our innovative High-Density surface ElectroMyoGraphy (HDsEMG) interface to measure the plantar
flexor neuromechanics during isolated ankle testing using dynamometry and functional tasks during walking on
differing grades. Our preliminary data demonstrate that the relative contributions of the primary plantar flexor
muscles can be modified by changing the knee angle during isolated and functional tasks. We will use this
experimental model system to test the mechanistic link between plantar flexor neuromechanics, Achilles
tendon loading biomechanics, and patient outcomes. In Aim 1, we will define neuromechanical profiles across
Achilles tendinopathy disease progression. In Aim 2, we will link neuromechanical profiles with Achilles tendon
loading profiles and stress imaging. By leveraging our large and well-characterized cohort of individuals with
Achilles tendinopathy, this Ancillary R01 will establish how neuromechanical mechanisms (Ancillary R01)
mediate complex biomechanical loading profiles of pathologic Achilles tendinopathy (Parent R01). This is a
necessary next step to develop precision rehabilitation that factor patient-specific neuromechanics and Achilles
tendon biomechanics. After successfully completing our proposed aims, we will test the clinical efficacy of
precision neuromechanical rehabilitation in a randomized clinical trial.

Grant Number: 5R01AR081062-04
NIH Institute/Center: NIH
Principal Investigator: Josh Baxter