Functional evaluation of the knee following ACL reconstruction: A complex dynamical systems perspective



Anterior cruciate ligament, Complex dynamical systems theory, Kinematic variability, Motion analysis, , Nonlinear analysis


In sports, anterior cruciate ligament (ACL) injuries are very frequent and, in most cases, it is necessary to resort to surgical reconstruction to restore the functionality and stability of the knee joint. For the experts, the fundamental clinical result is represented by the return to sport at the pre-injury level. Return to the sport, however, is complex and multifactorial. A functional asymmetry present after the resumption of sports activity is, in fact, a sign of a reduced ability of the knee to absorb dynamic forces. The dynamical systems theory (DST) applied to biological systems has emphasized the importance of the variability present in human movement, as a basis for the processes of adaptation to the surrounding environment. The human body is a complex and nonlinear system (a small input can produce a big change), therefore nonlinear analysis tools have been proposed to analyse its behaviour. This brief review provides an overview of the nonlinear analysis tools used in the past twenty years in the functional evaluation of the knee following ACL reconstruction. The analysis of kinematic variability of the knee provides important information on the changes in neuromuscular function that occur after the rupture and reconstruction of the ACL. This kind of analysis can lead to an understanding of the joint's ability to provide proprioceptive information and how the whole system processes them. The functional evaluation of the knee using nonlinear analysis tools could represent a new and more suitable functional measurement of the joint for the return to sport.


University of Salerno


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How to Cite

Albano, D., Romano, B., & Vastola, R. (2020). Functional evaluation of the knee following ACL reconstruction: A complex dynamical systems perspective. Journal of Human Sport and Exercise, 15(4proc), S1242-S1250. Retrieved from

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