Chronic Ankle Instability Diagnostic Tests Determining Underlying Deficits

Biomechanical Analysis, Complementary Examinations and Rehabilitative Management of Chronic Ankle Instability

Chronic ankle instability is a common condition in the active adult population and characterized by the occurrence of repeated giving way and/or recurrent ankle sprains. Multiple underlying deficits have been proposed, among which ankle muscle strength deficits, proprioception deficits, ( static and dynamic balance disorders, and articular laxity. Unfortunately, no consensus exists on which clinical tests should be realized to determine if one of these underlying deficits is predominant and as a result could guide the rehabilitation process. The study hypothesis is that people with chronic ankle instability might be heterogenous and could be divided in different subgroups as a function of underlying deficits. Therefore, this study aims to evaluate the capacity of different clinical tests to differentiate people with chronic ankle instability from healthy people as well as between each other.

Inclusion Criteria:

• Case subject : at least one initial lateral ankle sprain more than 12 months before inclusion
• Case subject : at least one residual symptom among (1) giving way, (2) sensation of instability, (3) recurrent ankle sprain. This item is confirmed by a score inferior than 24 on the Chronic Ankle Instability Tool (CAIT)
• Case subject : Impact on activities of daily living and sport, confirmed by a score of less than 90% on the Foot and Ankle Ability Measure (FAAM) and less than 80% on FAAM-- - -- Control subject : matched by age and sex to case subjects

Exclusion Criteria:

• Surgery of one of the lower limbs less than 3 years ago
• Presence of heavy pain (EVA > 8) regardless of its origin
• Acute lateral ankle sprain less than 4 months before inclusion
• Neurological disorders of any kind
• Medical treatment (drugs) interfering with muscle tone, balance and proprioception disorders
• Pregnant or breastfeeding women
• Body mass index > 30
• Bilateral chronic ankle instability