How ankle evertor fatigue affects force sense and muscle activation in people with chronic ankle instability
Effects of Ankle Evertor Fatigue on Force Sense and Neuromuscular Activation During Submaximal Isometric Contractions in Individuals With and Without Chronic Ankle Instability
This project will test whether tiring the muscles that turn the foot outward changes how people with chronic ankle instability sense force and activate their ankle muscles.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 50 (estimated) |
| Ages | 18 Years to 45 Years |
| Sex | All |
| Sponsor | University of Ljubljana Academic / other |
| Locations | 1 site (Ljubljana) |
| Trial ID | NCT07252219 on ClinicalTrials.gov |
What this trial studies
This is an observational, laboratory-based comparison of people with chronic ankle instability (CAI) and healthy controls using an isokinetic dynamometer. Participants perform maximal voluntary isometric contractions and force-matching tasks at 25% and 50% of MVIC before and after an ankle evertor fatigue protocol consisting of isotonic eversion at 30% MVIC until visible fatigue. The protocol includes repeated 5-second trials with and without visual feedback while neuromuscular activation and force perception are recorded on the symptomatic side (or the side with the lower CAIT score for bilateral CAI). Testing sessions last about 45–60 minutes following a 20-minute familiarization period.
Who should consider this trial
Good fit: Ideal candidates are adults 18–45 with diagnosed chronic ankle instability (first sprain ≥1 year ago, CAIT score <24, at least 3 months since last sprain) or healthy age-matched controls with no lower-limb injury history or neurological impairment.
Not a fit: People outside the 18–45 age range, those with recent major lower-limb surgery, other ankle joint pathologies, or peripheral/central neurological impairments are unlikely to benefit or be eligible.
Why it matters
Potential benefit: If successful, the results could help clinicians design rehabilitation and training programs that reduce re-injury by targeting fatigue-related deficits in force sense and muscle activation.
How similar studies have performed: Prior laboratory studies have shown that muscle fatigue can impair proprioception and alter muscle activation, but findings in CAI populations are mixed and not yet definitive.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion criteria for the healthy control group (no CAI): * Age between 18 and 45 years, * No history of injuries or surgical procedures to the lower limbs, * No peripheral or central neurological impairments. Inclusion criteria for the chronic ankle instability (CAI) group: * Age between 18 and 45 years, * No history of major surgical procedures on the lower limbs * No peripheral or central neurological impairments, * Diagnosed chronic ankle instability: * First ankle sprain occurred at least one year prior to testing, * At least three months since the most recent ankle sprain, * Subjective feeling of ankle instability - CAIT (Cumberland Ankle Instability Tool) score \< 24. Exclusion criteria for the CAI group: \- Other pathologies of the ankle joint.
Where this trial is running
Ljubljana
- Faculty of Health Sciences — Ljubljana, Slovenia (Recruiting)
Study contacts
- Study coordinator: Alan Kacin, PhD, PT, Prof
- Email: alan.kacin@zf.uni-lj.si
- Phone: +38613001119
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.