Applying principles of Motor learning to ACL rehab
Injuries of the anterior cruciate ligament (ACL) in sports remain a serious problem in the broadest sense. This burden has not gone unnoticed, and over the past decades preventive efforts have been introduced.
The efficacy of ACL injury prevention programs show that about a 52% reduction of ACL injury risk can be achieved for female athletes. The literature is scarce regarding the efficacy of prevention programs to reduce ACL injuries in male athletes. The results of large-scale RCTs have supported for example the efficacy of the FIFA 11+ in teams of amateur female and male and collegiate male soccer players. It should be noted however, that ACL injury reduction was only achieved in male players in the lower divisions but not those who played in the higher divisions.
In this Think Tank course we will elaborate in an interactive fashion on the large body of evidence supporting the efficacy of ACL injury prevention programs with the purpose to identify areas that may have the potential to improve current outcome. The following topics will be discussed:
- In ACL injury prevention, especially the neuromuscular factors have received widespread attention as these can be viewed as modifiable. Subsequently, various screening test have been develop to identify athletes at risk for an ACL injury. These tests are based on a linear relationship between a given risk factors and (future) injury. recently a complex system approach has been proposed. This emphasizes a non-linear interaction between risk factors from different scales (biomechanical, psychological, physiological and training characteristics) and a web of determinants and and how these contribute to injuries.
- ACL injury prevention programs entail a combination of plyometrics, strength training, agility and balance exercises. The contention is that risk factors (only known for females) can be targeted. The premise is that through such exercises, the athlete acquires sufficient neuromuscular control and strength to handle unexpected situations such as a sudden change of planned movements, that may result in high joint loads.Hence, the preventive effectiveness largely depends on feedback mechanisms which will be activated once the athlete encounters a potential injury mechanism. However, in any injury mechanism, an athlete is embedded in a playing situation where external factors such as possession of a ball and position of team mates and opponents are involved. These attentional and environmental interactions effects on neuromuscular function are largely not addressed in current ACL injury prevention programs.
- The instructions given in ACL injury prevention induce an internal focus of attention - that is attention is directed towards one’s own movements. In the motor learning domain direct this is defined as an internal focus of attention. Retention of motor skills in ACL injury prevention programs with IF instructions are generally not sustained over time.