July 2009

In the Moment: Sports Medicine

Study: Repair ACL early in kids
Waiting risks meniscal, chondral defects

by Jordana Bieze Foster

Kids may think they have time on their side, but that’s not the case when it comes to anterior cruciate ligament reconstruction, according to research presented in July at the annual meeting of the American Orthopaedic Society for Sports Medicine.

Despite concerns that surgery could impair growth in skeletally immature patients, the findings indicate that delaying ACL repair until after the physes have closed  puts young athletes at significantly increased risk of medial meniscal tears and chondral defects.

Researchers from Children’s Hospital of Philadelphia and the University of Pennsylvania School of Medicine retrospectively analyzed the records of 69 children (70 knees) under the age of 14 who had undergone ACL reconstruction. Of those, 29 procedures occurred more than 12 weeks after the initial injury. At surgery, those 29 ACL tears were significantly more likely to also have meniscal and cartilage injuries than the tears that were repaired early.

“The risk of inducing a growth disturbance with early reconstruction of a torn ACL must be balanced against the risk of further knee damage by delaying treatment until closer to skeletal maturity,” said Theodore J. Ganley, MD, director of the Sports Medicine and Performance Center at CHOP and senior author of the study.  “Our results highlight and help quantify the risk associated with delaying ACL reconstruction in young athletes and the need for continued injury prevention efforts.”

Delayed treatment was significantly associated with the number and severity of medial meniscal tears, including irreparable tears. Time to surgery was found to be an independent risk factor for medial meniscus tears, with an odds ratio of 4.1. The delay did not significantly affect the rate of lateral meniscus tears.
Procedures delayed more than 12 weeks were also significantly associated with higher-grade lateral compartment and patellotrochlear chondral injuries. Time to surgery was an independent risk factor for  chondral injuries in both locations, with an odds ratio of 11.3 for the lateral compartment and 3.1 for patellotrochlear. Evidence of instability, even one episode, was also an independent risk factor for medial meniscal injury (OR 11.4) but not chondral injury.

The Philadelphia findings are consistent with those of a French group, published in the July issue of Knee Surgery, Sports Traumatology, Arthroscopy. In that study, researchers from the South Lyon Hospital Center found that medial meniscal tears were more than twice as prevalent in those whose ACL reconstructions were delayed until skeletal maturity. The mean time to surgery was 30 months in those patients, compared to 13.5 months in cases where reconstruction was performed with open physes. The French team also found that at follow up, a mean of 27 months after surgery, those whose procedures were performed sooner had significantly lower subjective International Knee Documentation Committee (IKDC) scores than those in the delayed group.

Neither study reported any growth disturbances at follow up.

The Philadelphia researchers theorize that compliance may be a key issue. In their study, prior to surgery, each patient was instructed to wear a custom ACL brace and refrain from sports or other activities involving cutting, jumping or pivoting. But return to sports with a brace while awaiting reconstruction was not found to be an independent risk factor for either meniscal or chondral complications, suggesting that patients may not be compliant with other aspects of the prescribed activity modifications.

“Kids will be kids, no matter what restrictions we put on them,” the authors wrote.

Shape-based running shoe selection fails to reduce injury rates in military
Running shoe selection based solely on plantar shape does not significantly decrease injury rates, according to a military study presented in May at the annual meeting of the American College of Sports Medicine.
Researchers from the U.S. Army Center for Health Promotion and Preventive Medicine randomized recruits to experimental (1089 men, 468 women) or control (1079 men, 483 women) groups. In the experimental group, subjects were assigned a running shoe type based on their plantar shape, determined using a light box.

Those with large plantar shapes were assumed to have low arches and assigned a motion control shoe; smaller plantar shapes were assumed to represent high arches and assigned a cushioned shoe; all others received a stability shoe. All control subjects also received stability shoes.

After nine weeks of basic training, during which the recruits ran about four times per week, injury risk did not differ significantly between groups, for either gender. Experimental/control hazard ratios were 1.11 for men and 1.14 for women after controlling for other injury risk factors.

Ligament load data dictate cautious use of lunges in PCL rehabilitation

Loads generated during weight bearing forward and side lunges may be a cause for concern in the early stages of posterior cruciate ligament rehabilitation, according to research from California State University Sacramento.

Investigators measured tensile forces on the anterior and posterior cruciate ligaments in nine male and nine female subjects as they performed forward and side lunges, with and without a stride. No significant loading was observed in the ACL. In the PCL, forces ranged from 205 N to 765 N, and were greatest for the forward lunge long at maximum knee flexion during both ascent (60º – 80º) and descent (40º – 80º). Adding a stride did not change loading significantly, although forces during the forward lunge were lower with a stride than without.

“While the PCL is still healing, both the forward and side lunges should be used cautiously, especially the forward lunge at higher knee angles,” said Rafael Escamilla, PT, PhD, professor of physical therapy at CSU-Sacramento, who presented the findings in May at the annual meeting of the American College of Sports Medicine.

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.