Understanding restoration of Achilles Tendon function after rupture (UNRESAT)

Main funder

Research Council of Finland

Funder's project number: 323168

Funds granted by main funder (€)

342 719,00

Funding program

Academy Project, AoF (Research Council of Finland)

Project timetable

Project start date: 01/09/2019

Project end date: 31/08/2023

Summary

Much debated treatment choices for acute Achilles tendon rupture are nonoperative treatment with early functional rehabilitation, and surgical treatment that has a greater infection risk. While the rate of nonoperative treatment is increasing, risk factors of rerupture or predictors of good recovery after nonoperative treatment are poorly understood. This prospective cohort (N=200 nonoperatively treated acute ruptures) focuses on the role of physical activity and novel biomechanical variables with specific research questions being: 1) Does physical activity level before the Achilles tendon rupture predict reruptures after non-operative tendon treatment? 2) Do physical activity level and other patient-reported outcomes about functional recovery return to the level before rupture within 1 year? 3) Which biomechanical variables (foot anatomy, muscle size, subtendon lengths, tendon stiffness, internal tendon displacement) or their changes within 1 year after treatment explain good functional recovery (plantarflexion strength, gastrocnemius muscle function during gait and patient-reported outcomes) after non-operative tendon treatment? All patients within Central Finland Health Care District with an acute (<14 days) Achilles tendon rupture and referred for either operative or nonoperative treatment with functional rehabilitation can volunteer. Healthy controls (N=100) will be recruited to obtain sufficient prevalence of smoking and overweight in age and sex matched comparison group. Assessments are done at 2 and 4 weeks (only clinic), 8 weeks, 6 months and 12 months after injury in clinic and biomechanics laboratory. Patient-reported outcomes are collected using UCLA, Tegner, Leppilahti Score and ATRS questionnaires. Objective physical activity for 7 days is assessed during normal daily life 3 times during 1 year. Novel associations between sport participation, daily physical activity, sedentary time, muscle function, tendon biomechanics, and clinical and patient-reported outcomes are expected. Such associations are likely to govern the efficacy of rehabilitation and prevention of reruptures. This patient-spesific knowledge obtained provides readily transferable knowledge for treatment and rehabilitation with societal impact. Ultimately, we may be able to create assessment tools for re-injury risk. Further, this multidisciplinary project develops an Achilles tendon model with three subtendons that will provide a future platform for patient-specific simulations.