Delayed ACL Surgery Appears To Increase Future Injury Risk in Young Athletes

Young athletes who suffer an anterior cruciate ligament (ACL) tear risk further injury unless they seek early treatment, according to a recent study from UH Rainbow Babies & Children Hospital and two collaborating institutions.

Orthopedic surgeons at UH Rainbow, the Hospital for Special Surgery, and Geisinger Medical Center evaluated 546 cases of ACL tear and whether each patient developed a medial meniscus tear after the initial ACL injury. They concluded that the longer a reconstructive surgery is delayed, the higher the risk of further injury. For each week that the surgical procedure was delayed, there was a 2 percent increased risk of a medial meniscal tear, compounding to a 22.8 percent increased risk over 10 weeks.

“When we're looking at these kids who have an ACL tear, we must consider how to optimize timing from injury to surgery to give patients the greatest opportunity for excellent outcomes," says study senior author and UH Rainbow pediatric orthopedic surgeon Justin Mistovich, MD.

“We know that, historically, kids who try to play without an intact ACL have risks of early-onset arthritis, including meniscal tears and articular cartilage damage,” he says. “But until now, we didn't really have great data on the timeframe for that risk."

Previous studies have used somewhat arbitrary time cut-offs to determine whether delaying ACL reconstructive surgery for one, six, 12, or 26 weeks was linked to further injury. This new study takes a different approach, measuring continuously how the risk increases over time.

“It makes a lot more sense to look at this variable of delay to surgery as a continuous variable instead of three or four different groupings of categorical classes," Dr. Mistovich says. “Nobody has ever really done that before. The power of the design of this study is that it would allow us to better categorize individual risk on a weekly basis and if there is increased risk as a function of that."

Early Care Is Important

For the study, the researchers retrospectively enrolled all pediatric patients at UH Rainbow and Geisinger Medical Center who had undergone ACL reconstruction between 2006 and 2018 into an ACL registry. Patients who did not know the date of their ACL injury were excluded. The researchers also noted each patient's sex, age, and BMI so as to be able to control for any confounding variables when looking at the role of surgical delay.

Beyond the general increased risk of further injury of 2 percent per every week surgery is delayed, the team also found some eye-opening results for a specific group – obese male patients. These patients had a 77.9 percent increased risk of medial meniscal tear for each 10-week delay in surgery.

Dr. Mistovich says he hopes this new study will help bolster the case to parents and young athletes that early care of an ACL injury is imperative.

“Historically, some kids have wanted to try to play with some sort of supporting brace to see if they could go out there and finish their season and then get their surgery done later," he says. “This study adds more compelling data to the risks and downsides to that approach. It also highlights the importance of getting a diagnosis in a timely fashion. There are a lot of things that can be considered in terms of access to care, duration of time between injury to specialty appointment or MRI. The sooner we can get these kids access to care, access to advanced imaging, and on the path to getting their knee motion improved so that they're ready for surgery and ultimately scheduled for surgery, the better the outcomes for them long-term." 

Dr. Mistovich says the study shows what can be accomplished when medical specialists collaborate across different institutions.

“Something I like to focus on with my patients is that when you see me for a sports injury, you're not just seeing me," he says. “For young athletes who have complex injuries, my colleagues at great institutions around the country and I all collaborate and share these cases, so we can all weigh in on them with a national team-based approach. I think our research approach tends to mirror our clinical approach in that involving surgeons from multiple institutions can lead to both better data sets and better clinical questions that we work to answer together. With this study, we have compelling data that shows that time to surgery is important, delays result in early knee damage, and if we can prevent those early adverse events from happening, perhaps we can get better long-term outcomes."

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At University Hospitals Rainbow Babies & Children’s, we focus not only on providing the best musculoskeletal care today, but also on how it will affect growth and development in the future. Through this lifelong approach to care, we deliver exceptional results that allow kids to move and play like kids while protecting their orthopedic quality of life as adults. Learn more about pediatric orthopedic care at UH Rainbow Babies & Children's Hospital.