Predicting Ankle and Knee Injury with a Jump Landing Test

Some of the most common injuries in team-sport athletes are to the ankle and knee. The high intensity running, changes of direction and in some cases, body contacts, make these joints vulnerable to both contact and non-contact related injuries such as ACL tears and ankle sprains. In effort to reduce the risk of these types of injuries in our athletes, many coaches employ movement screens to assess movement capacity and motor control. The concept here is to identify flexibility and mobility restrictions that prevent athletes from achieving basic movement patterns such as an overheat squat or lunge. Athlete can then be given an individualized program aimed at improving their limitations in hopes of ultimately reducing their risk of injury.

A less used screening tool that is showing high efficacy is the simple jump landing test. In this screen athletes either step off a box (~30 cm) or simply jump and land on both feet or on a single foot. The coach or trainer then observes the landing (performed several times) from various angles to see how the ankle, knee and hip joints handled the task. A new study published ahead of print in the International Journal of Sports Medicine evaluated the predictive ability of this test to for detecting which individuals were at risk of experiencing an ankle or knee injury. Seventy-five indoor team-sport athletes (i.e., basketball, volleyball, etc.) were screened with a bilateral and unilateral jump-landing stability test before their competitive season. The tests were recorded with specialized cameras that provided 3-dimensional kinematics and kinetics.

Injury reports by the team physical therapist showed that 11 acute ankle injuries as well as 6 acute and 7 overuse knee injuries were experienced during the competitive season. Statistical analyses showed that acute ankle injury was prevalent in athletes who demonstrated less stability in the forward and diagonal jump direction as well as greater ankle dorsiflexion moment during landing. Overuse knee injuries were higher in those with a smaller knee flexion moment and greater vertical ground reaction forced. Ultimately, the researchers found that athletes showing less unilateral stability and suboptimal landing technique were more likely to sustain an injury. The researchers therefore conclude that athletes should be taught proper landing mechanics and screened for them regularly to detect at-risk individuals and direct attention to them to reduce their risk of injury.

 

Reference:

Van der Does, HTD., et al. (2015) Jump Landing Characteristics Predicts Lower Extremity Injuries in Indoor Team Sports. International Journal of Sports Medicine. In press.