The risk of ACL injury increases for young athletes with fatigue, new research presented on Thursday by the American Orthopaedic Society for Sports Medicine shows.
The ACL is one of a pair of ligaments in the human knee. It plays a crucial role in the “restraining force” of the knee, meaning that it is important for rapid lateral and “cut” movements in sports. For sports, like volleyball, where most of the movement is lateral rather than straight-line, rehab time for ACL repair surgery takes between two and six months, depending on the severity of the tear and overall physical capacity. That can mean an even longer absence before an athlete returns to game shape.
ACL studies have become especially important in the 21st century, where an increase in participation in women’s athletics has led to the discovery that women are markedly more susceptible to ACL injuries than men – at a rate of 2-to-4 times more likely. Several studies have been done to try and discover why, without any solid conclusions yet – one done in April by Duke Health discounted a theory that said men’s and women’s knees move differently. The study by Duke showed, in fact, that ACL tears occur the same way in men as they do in women, which would contradict that theory.
The latest study utilized filming of young athletes doing vertical jumping and drop jumping. Using athletes from track & field, basketball, volleyball, and soccer, as fatigue increased, the ergonomics of the jumping indicated higher risks of ACL injury. Specifically, 14 of 22 athletes “demonstrating over 20% fatigue showed an increased ACL injury risk.” Female athletes and athletes over the age of 15 were more likely to demonstrate fatigued jumping that increased their risk of ACL injury.
The sample size of the study was small, but it does give coaches one more data point to help reduce the risk of injury in their athletes. The takeaway is something along the lines of structuring practices with conditioning work toward the end of the session, or more broadly to limit jumping late in practices or at points of practices where athletes might be most fatigued.
High Profile ACL injuries in the last year: