Depending on the age of the player, an ankle sprain is the injury most likely to occur. In general, an ankle sprain is the most common injury in younger players while players in higher levels of play and older players are most susceptible to a hamstring strain. Despite the frequency of injury, a complete understanding of the risks of ankle injury, especially a non-contact injury, continue to remain elusive.
To identify intrinsic risk factors for noncontact ankle sprains in professional soccer players. In the preseason, 100 third division professional soccer players were evaluated for possible risk factors of non-contact ankle sprains. Each player was assessed for ankle joint asymmetries in isokinetic strength, flexibility, proprioception, stability, injury history, body habitus, and limb dominance. All non-contact ankle sprains were recorded for a full competitive season (10 months). During the season, 17 players sustained at least 1 non-contact ankle sprain. Three factors were determined to be most predictive of a future ankle sprain: if the player had an asymmetry of eccentric isokinetic ankle flexion strength (odds ratio [OR] = 8.88; 95% CI: 1.95-40.36, P=0.005), increased body mass index (OR = 8.16; 95% CI: 1.42-46.63, P = .018), and increased body weight (OR = 5.72; 95% CI: 1.37-23.95, P = .017 ) each had a significantly higher risk of a noncontact ankle sprain.
The authors did not say whether stronger or the weaker ankle was at greatest risk of injury. The authors noted trends for younger age (OR = 0.28; 95% CI, 0.061-1.24, P = .092) and for presence of ankle laxity asymmetry (OR = 3.38; 95% CI, 0.82-14.00, P = .093) increased a player’s risk of future injury. Consistent with other published results, the authors cited asymmetry of eccentric strength of the ankle flexors coupled with an increased body mass (in this sample, over the sample median of 73kg) and the subsequent increase in body mass index (greater than the median of 23.1) elevated the risk of an ankle sprain in the coming competitive season. Age and asymmetries in ankle laxity, while not significant in this study, do seem to be potential factors worth consideration. A preseason evaluation should be performed and should also include assessment of ankle strength which, when combined with information about body mass and BMI, can alert a physician to players at highest risk for non-contact ankle sprains during the coming season.