Risks remain high after reconstruction
Female soccer players recovering from anterior cruciate ligament (ACL) reconstruction may benefit from neuromuscular training to prevent future injury, according to research from St. Louis presented this month at the annual meeting of the American Academy of Orthopaedic Surgeons (AAOS).
By Jordana Bieze Foster
In a separate AAOS presentation, a Swedish study of neuromuscular training to prevent primary ACL injury in female soccer players suggests that as little as 15 minutes of training per week can have significant benefits.
Gender differences in primary ACL injury rates in soccer players are well established, but the St. Louis study suggests these differences persist after ligament reconstruction.
“There is an increased risk for future ACL injury following reconstruction in female soccer players,” said Robert H. Brophy, MD, assistant professor of orthopedic surgery at Washington University School of Medicine in St. Louis, who presented his group’s findings at the AAOS meeting.
Using the prospective Multicenter Orthopaedic Outcomes Network (MOON) patient database, investigators analyzed 100 individuals (45 women) who had undergone ACL reconstruction and who identified soccer as their primary or secondary sport. They found no gender differences in time to return to play or in the percentage of athletes still playing soccer seven years after surgery, although men who had stopped playing were significantly more likely than women to cite their ACL injury as the reason.
Twelve of the soccer athletes underwent subsequent ACL surgery on either knee; the rate was significantly higher in women (20%) than in men (5.5%). A separate analysis of 988 ACL reconstruction patients (athletes and nonathletes) from the MOON database, also presented at the AAOS meeting, found an identical rate of surgery for subsequent ACL injury on either limb at six years, but did not find that this rate differed by gender.
This discrepancy suggests that neuromuscular training, which has been linked to reduced primary injury rates in previous soccer studies, may also be warranted in female soccer players who have undergone ACL reconstruction.
The soccer study also found that athletes in whom the initial reconstruction was performed on the nondominant limb were significantly more likely to undergo contralateral reconstruction than those who initially injured the dominant limb—underscoring the need for preventive training programs that emphasize both limbs.
A Swedish study presented at the AAOS meeting added to the growing body of evidence that such training programs can prevent primary ACL injuries in female soccer players, but was particularly remarkable in that significant improvement was seen even in athletes who trained for as little as 15 minutes per week.
Researchers from Hassleholm-Kristianstad Hospitals in Hassleholm, Sweden, cluster-randomized 309 teams of adolescent female soccer players (4564 players) to intervention and control groups. The intervention group was assigned to a 15-minute neuromuscular warm-up program twice weekly for a single season, while the control group was asked to train and play as usual. The intervention included six exercises progressed through four degrees of difficulty. (The study protocol was published in 2009 in the online journal BMC Musculoskeletal Disorders.)
During the season, the ACL injury rate was 64% lower in the intervention group than in the control group, a significant difference. If only “compliant” athletes (defined as those who attended at least one session per week) were included, that difference improved to 83%.
“We feel that neuromuscular training should be part of the warm up for adolescent female soccer players,” said Markus Walden, MD, PhD, an orthopedic surgeon at the hospital, who presented his group’s findings at the AAOS meeting.
Brophy RH, Schmitz L, Wright RW, Spindler KP. Gender based differences in outcomes following ACL reconstruction in soccer athletes from MOON cohort. Presented at annual meeting of the American Academy of Orthopaedic Surgeons, San Francisco, February 2012: Abstract 97.
Hettrich C, Dunn W, Reinke EKK, et al. What is the rate of subsequent surgery following ACL reconstruction in the MOON cohort? Presented at annual meeting of the American Academy of Orthopaedic Surgeons, San Francisco, February 2012: Abstract 98.
Walden M, Atroshi I, Magnusson H, et al. A randomized trial of anterior cruciate ligament injury prevention in adolescent female soccer players. Presented at annual meeting of the American Academy of Orthopaedic Surgeons, San Francisco, February 2012: Abstract 95.
Hägglund M, Waldén M, Atroshi I. Preventing knee injuries in adolescent female football players – design of a cluster randomized controlled trial. BMC Musculoskelet Disord 2009; 10:75.