ACL Tears in Youth Soccer Players
By Michael Morris, MD, Seattle Sounders FC Team Medical Director and Orthopedic Surgeon
ACL stands for anterior cruciate ligament. Ligaments are structures that attach bones together. The anterior cruciate ligament is one of four ligaments in the knee. Unfortunately, tears of the anterior cruciate ligament are one of the most common knee injuries in youth soccer players.
It is estimated that over 45,000 female athletes in the United States under 19 years of age sustain an ACL tear each year. ACL tears occur 6-8 times more often in women than in men. Contact is not necessary to sustain an ACL tear. In fact, over 75 percent of ACL tears occur without contact, typically with deceleration, cutting and pivoting activities.
An ACL tear is a devastating injury to a young athlete. The recovery for return to play is at least six months, and typically it can take up to a year to fully return to the previous level of play. It affects not only the player, but their parents, their coaches and their team.
Once the ACL is torn, it does not heal. Absence of the anterior cruciate ligament leads to repetitive instability bouts in the knee, causing it to buckle and give way. Obviously, this makes it difficult to continue playing soccer, but more importantly, it can lead to further damage in the knee, including meniscal tears and earlier arthritis.
The diagnosis of an ACL tear is made by the history as well as physical examination. Normally, one tears their ACL with a significant twisting injury to the knee. Over 90 percent of patients reveal that they heard a pop in the knee, and swelling to some extent occurs in all ACL tears. Studies have shown that more than 70 percent of injuries to the knee that develop swelling in the first 24 hours are related to an ACL tear. Therefore, any player with acute swelling in the knee should be suspected of having an ACL tear until proven otherwise. Evaluation by a physician in this situation is essential. The diagnosis of ACL tear can generally be made on physical examination, but MRI is oftentimes recommended.
Once an ACL tear has been diagnosed in a young, active athlete, the standard of care is surgical reconstruction of the ligament. The ligament itself cannot be primarily repaired, but must be replaced with another piece of tissue. The most commonly used grafts are the hamstring tendon, patellar tendon and cadaver tendon. There is no perfect graft. Each of these have pros and cons. Looking at ACL reconstructions in all age groups and activity levels, there is no evidence that any graft is superior to the other. However, in a young active athlete, failure of the reconstruction with rupture of the graft occurs in 10-30 percent of players. The patellar tendon has been shown to be the graft with the least failure rate. This is the graft we usually recommend in our professional soccer players as well as youth elite soccer players.
Media reports seem to suggest that everyone recovers from ACL surgery without issues. Alex Morgan and Megan Rapinoe have both returned to high-level play after ACL reconstructions. Unfortunately, this is not true for all players. In the National Football League, 37 percent of players who sustain an ACL tear never play another game. Studies of youth soccer players show that only 70 percent return fully to their previous level of play after ACL surgery.
After ACL reconstruction, extensive rehabilitation is required. Typically, it is 6-9 months before the athlete can return to soccer play. The type of rehabilitation program is critical, not only to recover from the initial surgery, but to develop control and strength in the knee to prevent re-injures or rupture of the ACL graft.
Can ACL tears be prevented? Many studies have shown that a specific warm-up program of dynamic exercises that include dynamic stretching, core strengthening and proprioceptive (awareness of body position) training can significantly decrease the incidence of ACL tears in young women soccer players. These studies have shown a 50-80 percent decrease in ACL tears in teams that have utilized these programs. It would certainly then behoove all of us, including parents, coaches and team administrators to make sure that these types of programs are part of our youth soccer training activities.
For more information about the treatment of ACL tears visit https://www.virginiamason.org/ACL.