HIGH VOLUME ACL reconstruction is one of the most common operations in sports medicine, with approximately 100,000 patients undergoing the procedure each year.

More and more young athletes are suffering anterior cruciate ligament tears, a devastating injury from which it can take up to a year to recover. The ultimate cause for this increase is unclear, but one thing's for certain: It's time to get ready for a steady stream of highly competitive kids who want to return to action soon after feeling — and hearing — their knees pop on local fields, courts and rinks.

Serious athletes
While ACL injuries are far more common among adults and skeletally mature younger athletes, the incidence of ACL tears in skeletally immature athletes appears to be increasing. Why? The orthopedic community isn't quite sure. Certainly more kids play youth sports than ever before and the media's attention on related injuries has risen dramatically. The trend for earlier single-sport specialization might also play a part in the rise of ACL injuries in younger athletes. ACL injuries occur most often in football and girls' soccer, but certainly aren't limited to those 2 sports.

That sports medicine surgeons are more aware of youths tearing their ACLs contributes to the growing number of reported injuries. Surgeons are more likely than ever to order advanced imaging such as MRIs to diagnose traumatic knee injuries in young athletes.

Young kids diagnosed with torn ACLs were historically treated without surgery. Surgeons feared creating leg-length differences or angular deformities of the knee by drilling holes through growth plates. Instead, they often recommended bracing, avoiding sports and waiting until athletes reached maturity before performing surgery.

Unfortunately, non-operative treatment comes with its own risks. The ACL does not heal on its own, and braces often do not effectively stabilize the knee. Several recent studies have documented a significant increase in irreparable meniscus tears and articular cartilage damage in kids with ACL-deficient knees. These secondary injuries can lead to permanent degeneration of the knee, but surgery to restore knee stability could prevent this long-term damage.

Surgery sooner
Returns from ACL tears almost always require surgery, and sports medicine surgeons are opting to surgically treat ACL tears earlier, even in very young children. A number of different techniques for reconstructing the ACL have been developed. The preferred technique involves many different factors, including the patient's age, skeletal maturity level, and surgeon preference and level of comfort.

The common feature of all the techniques for ACL reconstruction in skeletally immature athletes is the attempt to partially or completely avoid injury to the growth plates in the distal femur and the knee's proximal tibia. These procedures almost always use soft tissue grafts (mainly hamstring tendons) instead of the common bone-patella and tendon-bone grafts. Traditional bone plugs would likely cause a growth arrest if anchored across a physis.

For very young children with many years until puberty, surgeons often try to completely avoid drilling through the growth plates. The patient's ilio-tibial band or hamstring tendons can be harvested and placed through tunnels drilled in ways to avoid the plates. The screws, buttons or staples that fix the grafts are placed away from the physes.

As athletes approach skeletal maturity, surgical options increase. Techniques that place tunnels through 1 or both growth plates can be used with little risk of leg-length discrepancy or angular deformity. Some surgeons argue that these transphyseal techniques can be performed in very young children as long as the tunnels are drilled carefully to minimize violation of the physes.

Surgical treatment of a pediatric ACL injury therefore requires technical savvy and meticulous attention to create and place a graft that restores knee stability and minimizes growth-inhibiting risks. Fortunately, more sports medicine surgeons than ever seem willing and able to perform this complex surgery.

Get ready
For ACL reconstruction in pediatric cases, a variety of additional equipment and implants might be needed (see "Outfit the OR for Young Athletes"). C-arm fluoroscopy, or even CT imagery, helps surgeons avoid the growth plates while drilling. Different instruments to drill tunnels and implants to fix grafts are needed, depending on which technique is used for a given patient.

These surgeries often require facilities to buy or use equipment that they don't own and opt not to purchase in bulk. And scrub nurses and circulators often are much less familiar with the techniques and instruments. Having vendor reps present during the case can help your surgical team anticipate the need for different implants and instruments, and help guide their actions.

Surgeons will continue to refine ACL techniques as instrumentation improves and long-term outcome data confirm the efficacy and safety of the procedure. You and your surgical team should prepare now to treat pediatric patients. There's little doubt ACL reconstruction in young athletes will likely become even more common in the coming years.