A variety of factors at play have led to a decades-long increase in ACL tears.
Many sports enthusiasts and fantasy sports’ fans cringe when they read that their favorite athlete will be sidelined for the rest of the season because of an ACL tear. And in recent years, the cringing has become all too familiar as more and more athletes are sustaining major knee injuries. While it's tough to pinpoint a singular cause for the increased incidence of ACL tears across all sports levels – from professional athletes to youth sports participants – some crucial factors are likely contributors.
First and most positively, medicine today has evolved so that ACL injury is more easily identified and readily diagnosed. From specific tests used in a physical evaluation to advanced imaging studies that can confirm a physician's suspicion, gone are the days that ACL tears were overlooked or misdiagnosed. And those days aren't too far back in our rearview mirrors. It wasn't all that long ago when an athlete's ACL injury was found incidentally when some other catastrophic knee damage had occurred and wound up rendering the player unable to continue their sports career. Thanks to a number of medical pioneers who helped paved the way, today's ACL tear is recognized and treated in a much more timely manner.
An athlete's workload today is vastly different than what it was just 50 years ago. For example, players in the NFL, NBA, MLB and NHL, were everyday guys whose lives didn't revolve around their specific sport. Most had a regular job off the field and used training camp to get in shape for the season ahead. Fast forward to today. Players live and breathe the game as they spend countless hours building their strength, speed, and stamina to perform at an elite level. Off-season? There is no such thing for the professional athlete who is singularly focused on enhancing his craft every day and in every way.
As with any sport or activity, the more you practice and play it, the greater the risk of injury. Today's prevalence of ACL tears is partially attributable to increased training, practice, and playing time which places a far too heavy workload on an athlete's body.
In addition to increased workload demands on athletes at virtually every sport level, players today are also bigger, faster, and stronger than ever before in sports history. While one might think these attributes help protect a player against injury, that isn't always the case. Especially in sports where rapid changes of direction, stops, or force are involved, the risk of ACL injury increases. When you couple that threat with player size and increased velocity, it can even further exacerbate an athlete's ACL tear risk.
This is most certainly not an exhaustive list of all the factors at play concerning increased ACL tear propensity in recent years. Other factors include differentiated playing surfaces, such as turf vs. grass, that can affect the knee's biomechanics. Additionally, it's important to note that the increase in ACL tear prevalence is also elevated today in young athletes. The causes for this phenomenon can include those mentioned above, but sports specialization at a younger age is likely the most significant factor at play. Kids who specialize in a single sport at a younger age are at a far more elevated risk of injury, including ACL tear than multi-sport athletes.
The above information notwithstanding, I do have some good news. First, the vast majority of athletic programs where ACL injury is a risk have specific prevention and mitigation strategies in place to prevent ACL injury. In fact, we developed a preventive program consisting of a warm-up, plyometric and agility training to combat the possible deficiencies in strength and coordination of the stabilizer muscles that surround the knee joint. Because we knew that this program to Prevent Injury and Enhance Performance, PEP for short, had great potential for a number of sports, we made the agility portion of it sport-specific, so that more types and levels of athletes could benefit.
Whether it’s teenage girls playing volleyball or grown men playing NFL football, it may not seem like attention to strengthening the hips, thighs and hamstrings is what should be done to protect the knees. But with two years of study data backing our theories, I can tell you that it works. In fact, after implementing a prophylactic injury prevention program for one group of athletes, the results indicated an 88% overall reduction of ACL injury per athlete compared to a control group matched for skill and age. It is encouraging to see many athletic programs adopt such injury prevention programs and focus on them as much as they do on training for speed and power.
Also encouraging today is that, while many ACL tears might be season-ending, it is less often the case that they are career-ending. That is something to be incredible proud of from a medical perspective. This doesn't only affect the livelihoods of professional athletes but also trickles down to collegiate players and youth athletes as well. A life of sport shouldn't be cut short by an ACL tear, and today, it doesn’t have to.