title: Contralateral limb deficit after ACL-reconstruction: an analysis of early and late phase of rate of force development.
abstract: The aim of this study was to assess the effect of a unilateral anterior cruciate ligament reconstruction (ACLR) on maximum voluntary contraction (MVC) and explosive strength of both the involved limb and the uninvolved limb. Nineteen male athletes completed a standard isometric testing protocol 4 months post-ACLR, while 16 healthy participants served as a control group (CG). The explosive strength of the knee extensors and flexors was assessed as RFD obtained from the slope of the force-time curves over various time intervals. Both muscle groups of the involved limb had significantly lower MVC compared to the uninvolved. The involved limb also had significantly lower RFD in the late phase of contraction (140-250 ms) for both knee extensors and flexors (P < 0.05). There was no difference in MVC between the uninvolved limb and the CG. However, RFD of the uninvolved limb was lower compared to CG for both knee extensors (0-180 ms; P < 0.01) and flexors (0-150 ms; P < 0.05). ACLR leads to lower MVC and explosive strength of the involved limb. As a consequence of potential crossover (presumably neural-mediated) effects, explosive strength deficits could be bilateral, particularly in the early phase of the contraction (<100 ms).
authors.affiliation: a Faculty of Sport and Physical Education , University of Belgrade , Belgrade , Serbia.
authors.forename: Dragan M
authors.initials: DM
authors.lastname: Mirkov
authors.affiliation: b Institute for Medical Research, Department of Neurophysiology , University of Belgrade , Belgrade , Serbia.
authors.forename: Olivera M
authors.initials: OM
authors.lastname: Knezevic
authors.affiliation: c Human Performance Lab , Schulthess Clinic , Zurich , Switzerland.
authors.forename: Nicola A
authors.initials: NA
authors.lastname: Maffiuletti
authors.affiliation: d Clinical Centre of Serbia , Institute for Orthopaedic Surgery and Traumatology , Belgrade , Serbia.
authors.forename: Marko
authors.initials: M
authors.lastname: Kadija
authors.affiliation: a Faculty of Sport and Physical Education , University of Belgrade , Belgrade , Serbia.
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Nedeljkovic
authors.affiliation: e Department of Kinesiology and Applied Physiology; Biomechanics and Movement Science Graduate Program , University of Delaware , Newark , Delaware , USA.
authors.forename: Slobodan
authors.initials: S
authors.lastname: Jaric
mesh_terms: D059549:Anterior Cruciate Ligament Reconstruction; D003430:Cross-Sectional Studies; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D007717:Knee / Q000502:physiology*; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D011184:Postoperative Period; D052097:Quadriceps Muscle / Q000502:physiology; D055815:Young Adult
keywords: Quadriceps; arthrogenic inhibition; hamstrings; rate of force development