Balance Deficits in Recreational Athletes with Chronic Ankle Instability (Original Research) (Report‪)‬

Ankle sprains are one of the most common lower extremity injuries. According to the National Collegiate Athletic Association, ankle, (1) sprains are the most common injury in men and women who participate in soccer, basketball, and volleyball. Most ankle sprains are inversion injuries that damage the lateral ligaments of the ankle. (2) Up to 73% of individuals who sprain their ankles have residual symptoms including pain, repeated sprains, and episodes of "giving way." (3) Individuals with chronic ankle instability (CAI) experience frequent sprains, pain, and instability and have unknown long-term consequences to joint health. As the joint becomes unstable over time and continues to "roll" past its physiologic limits, the risk of damaging the articular surfaces within the joint and developing osteoarthritis increases. (4) In previous research, investigators (5-10) have identified static and dynamic balance deficits during single-leg stance in the affected limb of individuals with CAI; however, other authors (11-13) have reported no differences. Static balance means maintaining the center of mass over a stationary base of support, (14) such as maintaining balance during quiet stance. Dynamic balance means maintaining the center of mass over the base of support when the base of support is moving or when an external perturbation is applied to the body. In these studies, the investigators used different measures of postural stability, which may have contributed to the differences in results. (5-14) Additionally, in their study of an active population, Hoffman and Koceja (15) asserted that static measures may not relate well to dynamic measures, which are more indicative of functional ability and may be more applicable to a physically active population. The way that unilateral or bilateral CAI affects the contralateral limb and the spontaneous self-organization of the sensorimotor system is unclear. Rozzi et al (8) reported minor balance deficits in the uninvolved limb in individuals with unilateral CAI, and Caulfield and Garrett (16) attributed changes in landing pattern to "alterations in central programming at the spinal level." Using a double-leg stance may reveal possible central programming deficits and emphasize the interplay between the involved limb and overall control of body motion. Balance deficits in double-leg stance in subjects with CAI have not been assessed. Deficits identified in this stable position may provide evidence for the change in basic motor control strategies in subjects with CAI.