Anterior cruciate ligament (ACL) tears are common in people who are active in cutting and pivoting sports such as skiing, soccer and lacrosse. Female athletes have up to nine times higher incidence rates than that of males. In addition, female athletes—especially those at competitive high school and college levels—have a higher risk of ACL retear, a lower chance of returning to sports or activity at the same level, and a tenfold increase in osteoarthritis of the knee later in life.
At Brigham and Women’s Hospital, the Chief of Women’s Sports Medicine, Elizabeth G. Matzkin, MD, seeks to narrow that disparity and thereby level the playing field for female athletes. Her lifelong participation in sports and role as mom to three athletic daughters have strengthened this interest in orthopedic problems that impact women disproportionately.
“Historically, the sports medicine field has understudied and underrepresented female athletes,” she says. “The Brigham is changing that paradigm through our dedicated Women’s Sports Medicine Program, where we care for competitive athletes, recreational athletes and women who want to be more active.”
Graft Size Matters
Dr. Matzkin explains that in the case of reconstructing torn ACLs, female athletes are often set up for risk of a retear from the start because they have smaller anatomical knees, resulting in smaller notches, tunnel lengths and autografts for harvest.
Orthopedic literature shows that using grafts of less than 8 mm—and perhaps less than 9 mm—increases the risk of graft failure, leading Dr. Matzkin to question why anyone would use a graft smaller than 9 mm.
“Smaller grafts are an unintended consequence of a smaller patient, and that often means young female athletes,” she says. “As orthopedic surgeons, we need to find ways to avoid using smaller grafts.”
One way to do so, she says, is to look beyond the patellar tendon to hamstring and quadricep tendons when considering graft choices. Hamstring tendons can be especially robust if they are tripled, quadrupled or made into five-string grafts to create a greater diameter, instead of doubled as done traditionally.
An all-inside quadrupled semitendinosus graft technique, published in Arthroscopy, led to an improvement in functional outcomes at one and two years postoperatively in both male and female patients. If a 9 mm or larger size isn’t possible by quadrupling the semitendinosus, a gracilis tendon can be added.
The technique uses an independent femoral guide for easier anatomic placement of the femoral tunnel. In addition, it avoids the potential risks of a short tunnel, posterior wall blowout and impingement of the lateral wall of the intercondylar notch.
“Improvements in surgical technique and having an anatomic femoral tunnel of adequate length can help ensure female patients have outcomes equivalent to male patients,” Dr. Matzkin says.
Quadricep tendons also are becoming a more popular graft choice, given their thicker size and robust properties compared with patellar tendons. Dr. Matzkin suggests using MRI to make preoperative measurements or estimates of graft size.
Facilitating a Return to Sports
According to Dr. Matzkin, ACL reconstruction is effective in getting female athletes back to doing what they want to do—returning to sports at their previous level—and keeping them active as long as possible. It is one of the many services offered by the Women’s Sports Medicine Program, which focuses on treating injuries through innovative surgical techniques and deliberate postoperative rehabilitation as well as helping to prevent injuries in the first place.
“We work with female athletes at all levels to make sure they’re getting proper training, physical therapy and sports psychology services,” Dr. Matzkin says. “Neuromuscular training that works on core, hip flexor, abductor, quad and hamstring strengthening is particularly important to teaching female athletes how to land, pivot and move better on the playing field, all of which helps to prevent ACL tears and other injuries.”