Publications
Silent mechanical adaptation: Passive mechanical properties of ankle-surrounding tissues in individuals with unilateral chronic ankle instability
Authors: Busra Seckinogullari Korkusuz 1, Suleyman Korkusuz 2
Affiliations:
- Kizilcahamam Vocational School of Health Services, Department of Therapy and Rehabilitation, Ankara University, Ankara, Turkiye
- Faculty of Health Sciences, Department of Physical Therapy and Rehabilitation, Atilim University, Ankara, Turkiye
Journal: Journal of Back and Musculoskeletal Rehabilitation - October 2026 (DOI: 10.1177/10538127261500496)
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Field & Applications:
- Medical
- Musculoskeletal disorder
- Orthopedics
- Musculoskeletal rehabilitation
- Muscle symmetry
Background: Chronic ankle instability (CAI) is a complex condition characterized by recurring sprains.
Objective: Our study aimed to compare the tone, stiffness, and elasticity of the periarticular muscles, Achilles tendon (AT), and plantar fascia (PF) between the affected and non-affected limbs of individuals with unilateral CAI.
Methods: The cross-sectional study included 75 volunteers aged 18 to 45 years who had been diagnosed with CAI by a physician. Ankle instability was assessed using the Identification of Functional Ankle Instability (IdFAI). Passive mechanical properties (PMP), including frequency, stiffness, and logarithmic decrement, of the tibialis anterior (TA), peroneus longus (PL), medial and lateral gastrocnemius (MGC – LGC), AT, and PF were assessed bilaterally using the MyotonPRO. PMP were compared between sides, and relationships between IdFAI scores and PMP on the affected side were examined.
Results: The mean age was 27.46 ± 4.23 years. Logarithmic decrement and stiffness values were higher on the affected side in the TA (p = 0.011, p = 0.027), PL (p = 0.017, p = 0.031), and PF (p = 0.020, p = 0.028) compared to the non-affected side. Logarithmic decrement was also higher in the MGC (p = 0.029) and LGC (p = 0.005). No significant difference in frequency was observed for any of these structures (p > 0.05). The AT showed no significant differences in frequency, stiffness, or logarithmic decrement between the affected and non-affected sides (p > 0.05).
Conclusions: CAI is a multidimensional pathology characterized by deterioration of the PMP of the surrounding muscles and PF. These findings suggest that management of CAI should include interventions aimed at improving myofascial tissue elasticity in addition to neuromuscular rehabilitation.
Keywords: ankle instability, periarticular muscles, plantar fascia, Achilles tendon, myotonometer, passive mechanical properties
Our study demonstrates that CAI is a multidimensional pathology characterized not only by joint instability but also by deterioration of PMP in the surrounding ankle muscles and PF. These findings suggest that interventions aimed at improving myofascial tissue elasticity, rather than focusing solely on neuromuscular rehabilitation, are also important in the treatment of CAI. Future studies could further explore the role of these mechanical changes in CAI progression and how specific rehabilitation approaches may impact these tissue properties.