Relationship Between Muscle Strength and Balance

Inclusion Criteria: Anterior Cruciate Ligament (ACL) Injury Group: * Aged between 18 and 40 years * Diagnosed with a unilateral ACL injury 6 to 18 months prior to participation * Diagnosis confirmed by magnetic resonance imaging (MRI) * Ability to speak, read, and understand Turkish * Willingness to participate voluntarily in the study Chronic Ankle Instability (CAI) Group: * Aged between 18 and 40 years * Diagnosed with chronic ankle instability due to recurrent ankle sprains 6 to 18 months prior to participation * History of at least two ankle sprains * Ongoing symptoms of functional ankle instability (e.g., episodes of giving way, feelings of instability) * Ability to speak, read, and understand Turkish * Willingness to participate voluntarily in the study Healthy Control Group: * Aged between 18 and 40 years * No history of lower extremity injury or orthopedic diagnosis * Ability to speak, read, and understand Turkish * Willingness to participate voluntarily in the study Exclusion Criteria: * Presence of neurological, vestibular, or visual disorders that may affect balance * History of other orthopedic diseases or trauma * Presence of musculoskeletal disorders or cardiovascular comorbidities * History of physiotherapy, rehabilitation, or surgical intervention within the past 6 months