Purpose: The aim of this review was to determine whether postural control is impaired in patients with anterior cruciate ligament (ACL) injury as compared to healthy controls. Methods: The relevant papers were retrieved through electronic databases including PubMed, EMBASE, Web of Science, and Sport Discus followed by hand search and contact with the authors. Studies that evaluated static postural control during single-leg stance without applying external perturbations were included. Also, the patients should not have undergone ACL reconstruction or any surgical repair on the injured knee. Results: In total, 12 studies were selected for full review. The included studies showed larger postural sway amplitudes or velocities during single-leg stance on the injured leg and the uninjured leg when compared to healthy controls with medium to large effect size. Also, no significant difference was found between the injured and uninjured legs of ACL-injured patients during eyes open condition in all studies supported by small effect size. However, the within-group difference was found to be significant during eyes closed condition, with injured leg displaying larger sway. Conclusions: The present review indicates that postural control is impaired in both legs, especially injured leg. The result of within-group difference in eyes open condition confirms bilateral deficit of postural control. However, the within-group difference during eyes closed condition indicates again that ACL injury affects the injured leg more than the uninjured leg. In designing rehabilitation protocols, clinicians should consider training postural control of not just the injured but also the uninjured leg. Level of evidence: Systematic review of Level III for prognostic studies. © 2013 Springer-Verlag Berlin Heidelberg.
Negahban, H., Mazaheri, M., Kingma, I., & van Dieen, J. H. (2014). A systematic review of postural control during single-leg stance in patients with untreated anterior cruciate ligament injury. Knee Surgery, Sports Traumatology, Arthroscopy, 22(7), 1491-1504. https://doi.org/10.1007/s00167-013-2501-4