Findings contrast with prior studies
Lace-up ankle braces can significantly reduce the risk of ankle sprain in high school basketball players, even those with no history of injury, according to findings from Wisconsin that challenge current evidence-based thinking about prophylactic ankle bracing.
In a cluster randomized controlled trial, researchers from the University of Wisconsin in Madison studied ankle injury incidence in 1440 male and female high school basketball players, of whom half were randomized to wear a lace-up ankle brace during a single season. All players wore similar mid-top style shoes. An ankle sprain injury was defined as one that led the athlete to cease sports participation for that day and also miss the next day of practice or competition.
Ankle sprain injuries occurred in 3.6% of players in the braced group, compared to 11% of players in the control group. Overall, the ankle sprain rate was 0.47 per 1000 exposures in the braced players and 1.41 per 1000 exposures in the unbraced players. This difference was consistent regardless of whether players had a history of ankle sprain injury (0.83 vs 1.79 per 1000 exposures) or no history of injury (0.40 vs 1.35 per 1000 exposures).
Because athletes with a previous history of ankle sprain tend to have significantly more instability than those with no similar history, the findings may suggest that mechanical resistance to inversion may not be the primary mechanism by which lace-up bracing prevents injury.
“I used to believe there was a mechanical effect of ankle bracing. Now I’m starting to think there’s more of a neuromuscular effect,” said Tim McGuine, PhD, ATC, senior athletic trainer and research coordinator at the university, who presented the findings in Monaco in April.
Most previous studies of prophylactic ankle bracing in sports—and in basketball in particular—have found interventions to be more effective in athletes with a previous history of injury than those without, which makes sense intuitively given that history of prior ankle sprain is itself a risk factor for incident sprain. However, those studies involved rigid or semi-rigid bracing rather than lace-up devices.
For example, in a 1994 study in the American Journal of Sports Medicine, a study of intramural basketball players at West Point found that a semirigid brace was associated with significantly lower injury rates in braced than unbraced athletes overall (1.6 vs 5.2 per 1000 athlete exposures) but that the effect was more dramatic in those with a history of injury (1.4 vs 8.0 per 1000 athlete exposures).
Similarly, a 2007 prospective cohort study of female Greek professional basketball players published in the Journal of Athletic Training found that unbraced athletes were 2.5 times more likely to be injured than braced athletes overall, but four times more likely if they had a previous history of injury.
One recent study in high school volleyball players actually came to the opposite conclusion, finding that rigid or semi-rigid bracing was associated with reduced injury risk only in athletes with no history of injury (see “Net gain for ankle bracing,” May 2010). That study, published in the April 2010 issue of Foot & Ankle International, did randomize one group of players to wear a nonrigid ankle brace, but no effect of bracing on injury risk was seen in that group regardless of injury history.