Clinical Question: Are balance exercises more effective at preventing ankle sprains than traditional strength and conditioning exercises among high school athletes?

Setting: Outpatient (any)

Study Design: Cluster randomized controlled trial (nonblinded)

Synopsis: The researchers conducted a cluster randomized controlled trial in which 55 high school soccer and basketball teams (523 girls, 242 boys) were randomized to their usual strength and conditioning program or to a five-phase balance program. Phases 1 to 4 each lasted one week and were completed before the start of the athletic season. The fifth phase was a maintenance phase in which participants performed the exercises three times each week for 10 minutes throughout the athletic season.

The program began with open-eye training on the floor and increased in complexity, ending with closed-eye exercises on a balance board. Because the rate of ankle sprains is a function of exposures, the athletic trainers at the schools tracked all coach-directed competition, practice, or conditioning sessions. In addition to measuring the rate of ankle sprains (assessed via intention to treat), they determined severity on the basis of the number of days lost to sports: minor (one to seven days), moderate (eight to 21 days), and severe (more than 21 days).

To return to play, injured athletes needed approval by the athletic trainer and physician; full ankle strength and pain-free range of motion; and the ability to complete a series of functional activities similar to the demands of his or her individual sport. The intervention group sustained fewer sprains (6.1 percent, 1.13 per 1,000 exposures) than the control group (9.9 percent, 1.87 per 1,000 exposures). Twenty-six high school soccer and basketball players would need to use this program to prevent one sprain per season.

The authors report that the program was more effective in preventing sprains in athletes with previous sprains; however, the study was not of sufficient power to determine if the program was also effective in the primary prevention of sprains. There was no statistically significant difference in sprain severity, but the study lacked the power for this to be conclusive.

Bottom Line: A structured balance exercise program is more effective than traditional strength and conditioning exercises in preventing ankle sprains in high school athletes. (Level of evidence: 2b−)