Take Home Points

  1. Implementation of injury prevention training was effective in limiting the loss of knee control in female athletes during puberty.

Anterior cruciate ligament (ACL) injuries are one of the most common injuries in sports. Female athletes between the ages of 14 and 19 years are among those who have the highest incidence of ACL injury (Otsuki 2014). Injury to the ACL during this age is a problem because surgery in skeletally immature patients might cause growth disruption. Surgery and rehabilitation prevent adolescents from participating in sports activities for a long period, affecting healthy physical development. The risk of developing osteoarthritis is significantly increased after an ACL injury (Otsuki 2014). This could be a problem that affects the quality of life as well.

One of the risk factors for developing ACL injuries is poor lower extremity movements. Studies have suggested that a combination of anterior tibial shear force, knee abduction, and internal tibial rotation can lead to ACL failure. Video analysis of actual injury cases showed that the main mechanisms of ACL injury were increased knee valgus motion with internal tibial rotation. A reduced knee flexion angle was observed in injury situations. Female athletes with an increased knee valgus motion and reduced knee flexion angle during landing are at a high risk of developing ACL injury (Otsuki 2014).
Otsuki (2014) evaluated the effects of injury prevention training on dynamic knee alignment in female basketball players specifically when the knee mechanics were changing during puberty. Sixty female junior high school basketball players participated and were divided into two groups: a training group (n = 32) and a control group (n = 28). The training group underwent an injury prevention program for 6 months, whereas the control group maintained a regular training routine. The program was modified considering basketball specific skills. The focus of this program was to ensure proper movement patterns, particularly avoiding knee valgus motion and encouraging knee flexion during landing and cutting. The program was 20 minutes long and was implemented as a warm‐up routine. The training group performed the program three times per week for 6 months. A six‐month training period was selected to observe the changes associated with growth. The initial training session was conducted by a physical therapist. To ensure that the exercises were correctly performed and to help advance, the therapist followed up with the subjects every two weeks. The coach was also trained on how to instruct athletes on each skill at the initial training session. The coach led the training during the two weeks between therapist follow‐ups. The control group performed their regular training routine for six months. Both groups did not perform any additional training or conditioning which may have had an influence on their landing performance. The knee valgus motion and knee flexion range of motion during a drop vertical jump were measured before and after the training period. The probability of a high knee abduction moment (pKAM) was also evaluated using an ACL injury prediction algorithm. The knee valgus motion was significantly increased in the control group, whereas it did not change in the training group. Similarly, the knee flexion range of motion was significantly decreased in the control group, whereas it was not changed in the training group. The pKAM was significantly increased in the control group, but not in the training group. Implementation of injury prevention training was effective in limiting the loss of knee control in female athletes during puberty. Lowering the risk of ACL injury might be possible in this population. ]
Implementation of injury prevention training can be affective in limiting the loss of dynamic knee control in female basketball players during puberty. Although injury prevention training was able to limit the changes in knee mechanics, no improvement was observed (Otsuki 2014). Studies have found that when evaluating high school female athlete’s injury prevention training improved knee mechanics in both the frontal and sagittal planes. It seems that the injury prevention training was not as effective in pubertal girls compared with post‐pubertal girls. This may be caused by changes in landing mechanics that pubertal girls naturally develop during this period. A rapid increase in height and weight might increase torque at the knee joint (Otsuki 2014). The width of the pelvis increases in girls during puberty. An increase in pelvic width might bring the hips to a more adducted position and therefore affect dynamic knee alignment. Studies have reported that female adolescents do not have enough neuromuscular development during puberty compared with male adolescents. Using injury prevention training could increase the neuromuscular system in female adolescents. Limiting the changes in knee mechanics during this period might be a starting point to prevent ACL injury. In some athletes, this might be enough to reduce the risk of ACL injury, while in those who are at very high risk further training would need to be done (Otsuki 2014).

1.   Otsuki R, Kuramochi R, Fukubayashi T. Effect of injury prevention training on knee mechanics in female adolescents during puberty. Int J Sports Phys Ther. 2014 Apr;9(2):149-56.

Written by Chris Barber, CPT