Three Important Factors in Child ACL Tears

Sometimes it seems like children are made of rubber. They fall or they injure themselves in some way but they get up and bounce back as if nothing ever happened. But in reality, that’s not always the case. And with more children and teens participating in sports activities, there has been a rise in the number of musculoskeletal injuries in this age group.

One of those injuries is a tear of the anterior cruciate ligament (ACL). The ACL is one of two ligaments that criss-cross inside the knee to give it stability. The ACL helps the knee bear the weight or load of our body while we move, twist, jump and turn.

When this type of injury affects an adult, the surgeon automatically looks for other damage as well. It is not uncommon with an ACL partial tear or complete rupture to have a torn meniscus and/or chondral (cartilage) damage.

But what about children? Are they just as prone to have additional injuries when the ACL is torn? And do their great powers of healing make it possible to delay surgery while we “wait-and-see” if they will recover? Those are the kinds of questions surgeons from the Children’s Medical Center in Dallas, Texas investigated in this study.

They reviewed the medical records of 371 pediatric patients who had surgery to reconstruct a torn ACL. Data analyzed from the charts included number of days between the injury and the surgery, age, weight, gender, and way the injury occurred. They were specifically looking for any factors that were linked with meniscal tears or chondral (cartilage) damage. The surgeons also wanted to know if a child had a meniscal tear, would it lead to further chondral injury?

This type of study has been done in adults and found that the longer the patient waits between ACL injury and surgery, the greater the risk of meniscal and chondral damage. And that can mean damage that can’t be repaired and that leads to arthritis and loss of knee function in time. A study like this could potentially save children from the same fate. And this is the first study this large to really help answer some of these questions.

They found three factors that increase the risk of poor outcomes and degenerative changes in the knee. The first was a time delay between when the injury happened and when treatment was received. Children who had surgery in the first 150 days (five months) had fewer meniscal tears compared with children whose surgery took place later.

And as you might expect, obese children putting greater load on the damaged tissue were more likely to experience additional injury to the meniscus and chondral surface of the joint. In all children, the presence of a meniscal tear also increased the risk of further chondral damage. Pediatric patients older than 15 years had a higher rate of meniscal tears.

There was no one particular sport that seemed to result in more ACL injuries than any other. And unlike some studies where males had more meniscal and chondral injuries, there was not a gender factor observed in this group of patients.

The results of this large series are very helpful for surgeons when trying to advise patients and families of those patients about what to do (surgery or not?) and when to do it (now or later?). Older, heavier patients may not want to wait before having the ACL reconstruction. Younger patients who are not obese may have more time to apply the wait-and-see approach to treatment.

The authors point out the need to continue to educate children and their families about the dangers of obesity. This is true not just to help prevent early-onset of diabetes and later problems such as heart disease but also the increased risk for musculoskeletal injuries. Such physical injuries can have a lifelong impact.