Novel ACL reconstruction technique in younger patients garners positive results two years post-surgery

A new study by researchers at Hospital for Special Surgery (HSS) in New York City presented today at the American Academy of Orthopaedic Surgeons (AAOS) 2022 Annual Meeting found that a novel surgical technique performed during anterior cruciate ligament (ACL) reconstruction in certain younger patients garnered positive results two years post-surgery.

The study evaluated the safety and efficacy of performing a lateral extra-articular tenodesis (LET) using a modified Lemaire technique (MLT) in conjunction with an ACL reconstruction in children and adolescents who are at an increased risk for a failed ACL reconstruction. Findings revealed the technique was associated with favorable patient-reported outcomes, high return to sports participation and low ACL re-tear rate.

Research has long demonstrated that young adolescents (typically in eighth and ninth grades) who return to a pivoting or high-risk high school sport have the highest re-tear rate after an ACL reconstruction.

In the New York City metro area alone, over 80 percent of ACL injuries in adolescents stem from participation in sports such as basketball, soccer, lacrosse, skiing and football.

The ACL, one of four major ligaments in the knee joint, helps maintain the knee's rotational stability and prevent the shinbone (tibia) from slipping in front of the thighbone (femur). It is especially vulnerable to injury from impact or athletic activities.

Currently, the standard-of-care surgical treatment for ACL tears is reconstruction. This involves placing a graft in the knee using a minimally invasive incision. Approximately 300,000 ACL reconstructions are performed annually in the United States. If the surgery fails, a revision procedure is necessary, which may result in higher rates of failure and lower rates of return to sport.

Reconstruction alone has not been sufficient for kids who haven't finished growing yet and want to stay active in sports."

Daniel W. Green, MD, MS, FAAP, FACS, senior author and pediatric orthopedic surgeon, HSS

"The risk of re-injury has been too high, leading to devastating consequences for a young athlete," added Frank A. Cordasco, MD, MS, lead author and sports medicine surgeon at HSS, who noted that this continues to be an important area of clinical research for sports medicine surgeons worldwide.

About a decade ago, surgeons in France innovated on the standard ACL reconstruction procedure after identifying elite soccer players as high risk for re-tear. They added the LET to the reconstruction and successfully demonstrated that this combination decreased the re-tear rate in adult soccer players by nearly 50 percent.

Drs. Cordasco and Green are two of the first physicians to apply this European technique to teenage athletes in North America. The physicians are dedicated to improving outcomes for adolescent athletes with ACL tears both clinically and through research.

"We are proud to have published one of the first surgical-technique papers describing how this procedure can be safely performed in young patients who still have open growth plates," said Dr. Green, who explained that this study is also unique in that it reports on two-year clinical outcomes in children who underwent this particular procedure.

"Not only does this technique not disturb children's growth plates or cause post-operative stiffness, but we also found that this demonstrates a remarkably low re-tear rate in this high-risk group," said Dr. Cordasco.

The study followed 61 patients between 11 and 19 years old who underwent simultaneous ACL reconstruction and LET with a minimum two-year follow-up; 97 percent of the patients participated in organized sports, with soccer being the most popular. These patients were identified as high risk when one or more of the following factors occurred: the patient participated in high-risk competitive sports such as football, lacrosse, soccer or basketball or that involved grade 3 pivot shift; had hyperlaxity; recurvatum; revision ACL reconstruction; contralateral ACL reconstruction; or chronic ACL insufficiency.

Depending on the patient's skeletal maturity, the ACL reconstruction was performed either by using full-thickness quadriceps tendon, bone-patellar tendon-bone autograft, all-epiphyseal or complete transphyseal techniques.

At a minimum two-year follow-up, the researchers looked at patient-reported outcome measures as well as data on returning to sports and any potential additional surgeries. The results were overwhelmingly positive, with a median Single Assessment Numeric Evaluation (SANE) score of 95%, where 100% represents normal function. The mean Pediatric International Knee Documentation Committee (Pedi-IKDC) score was 91, where 100 is interpreted to mean no limitations on daily living or sports activities. Patients also reported a median score of 27/30 on the HSS Functional Activity Brief Scale (HSS Pedi-FABS), which is a validated eight-item instrument to quantify the activity of children.

Nearly 92 percent of patients were able to return to sport. One patient had a revision ACL surgery and three had subsequent contralateral ACL reconstructions.

This study expanded upon work that Drs. Cordasco and Green published in 2020 that showed LET can be performed safely in skeletally immature athletes who underwent a quadriceps autograft ACL reconstruction.