Many young ACL surgery patients need second surgery later on

"This is the first study to evaluate, on a population level, the percentage of patients under age 21 who had subsequent ACL or non-ACL knee surgery following a primary anterior cruciate ligament reconstruction," said Emily Dodwell, MD, MPH, lead investigator and a pediatric orthopedic surgeon at Hospital for Special Surgery in New York City.

Compiling statistics from a New York State database, researchers found that eight percent of patients with a primary ACL reconstruction had another ACL surgery, and 14 percent had non-ACL knee surgery at a later date.

Dr. Dodwell presented the study at the annual meeting of the Pediatric Orthopaedic Society of North America, which took place April 29 to May 2 in Georgia. The research was also presented at the annual meeting of the American Academy of Orthopaedic Surgeons last month.

Researchers identified patients under age 21 who had surgery for a torn ACL between 1997 and 2010 using the Statewide Planning and Research Cooperative System (SPARCS) database for New York State. Patients were tracked for a subsequent ACL reconstruction or knee surgery for another injury, such as a torn meniscus, at a later date.

Investigators identified 23,912 primary pediatric ACL reconstructions in New York State. Out of those patients, 1,955 patients (8.2 percent) had a subsequent ACL reconstruction, and 3,341 patients (14 percent) had subsequent non-ACL knee surgery.

The median time lapse between the first and second ACL surgery was 1.6 years. The median time lapse between the first ACL reconstruction and surgery for another knee injury was 1.4 years. The median length of follow-up for all patients was 6.7 years.

Factors associated with needing a second ACL surgery included younger age at time of the first ACL repair; being male; white race; private insurance; higher hospital ACL volume; and higher surgeon ACL volume.

Factors associated with a second knee surgery for a non-ACL injury were younger age; being female; white race; private insurance; and higher hospital ACL volume.

Researchers noted that the study may underestimate the actual number of repeat ACL tears, as the database only included patients who underwent surgery, and did not include those who chose not to have additional surgery.

"The increasing rate of ACL injuries is concerning, although not surprising given greater participation in sports," Dr. Dodwell said. The study noted that children are starting sports at a younger age, playing for longer durations with greater intensity, and often concentrating on a single sport year round, resulting in overuse and acute injuries.

"For young people who have primary surgery to reconstruct a torn ACL, it is troubling that they have relatively high rates of subsequent ACL reconstruction or surgery for another knee injury. Further research is needed to determine factors associated with subsequent injury and surgery so we can implement strategies to keep our youth safe while engaging in sports," Dr. Dodwell said.

To that end, Hospital for Special Surgery recently received a 2.76 million dollar grant from a private foundation to establish a program aimed at preventing ACL injuries in young athletes.

The HSS Sports Medicine Injury Prevention Program, a five-year endeavor, will begin by reviewing best practices based on the latest research. The hospital will then launch a comprehensive campaign to raise awareness, informing and educating the public and professionals on injury prevention.

The initial focus will be on preventing ACL tears, one of the most common knee injuries among young athletes. Those who participate in cutting and pivoting sports such basketball, soccer, football, skiing and lacrosse are most prone to an ACL injury.