Alterations in Neuromuscular Control at the Knee in Individuals With Chronic Ankle Instability

Abstract

Context: Few authors have assessed neuromuscular kneestabilization strategies in individuals with chronic ankle instability (CAI) during functional activities.Objective: To investigate the influence of CAI on neuromuscular characteristics around the knee during a stop-jump task.Design: Case-control study. Setting: Research laboratory. Participants or Other Participants: A total of 19 participants with self-reported unilateral CAI and 19 healthy control participants volunteered for this study.Intervention(s): Participants performed double-legged, vertical stop-jump tasks onto a force plate, and we measured muscle activation around the knee of each limb.Main Outcome Measure(s): We calculated the integrated electromyography for the vastus medialis oblique, vastus lateralis, medial hamstrings, and lateral hamstrings muscles during the 100 ms before and after initial foot contacts with the force plate and normalized by the ensemble peak electromyographic value. Knee sagittal-plane kinematics were also analyzed during a stop-jump task. Conclusions: We found altered feed-forward patterns of the vastus medialis oblique and altered postlanding knee sagittalplane kinematics in the CAI group. These observations may provide insight regarding sensorimotor characteristics that may be associated with CAI. Results

Acute Ankle Sprain in a Mouse Model: Changes in Knee-Joint Space

“…Numerous researchers have reported the mechanical, [3][4][5][6] sensory, [7][8][9] and proximal changes [12][13][14][15] that occur after an ankle sprain and in those with CAI. Any of these negative alterations could lead to decreased physical activity.…”

“…Several groups [12][13][14][15][16] have reported alterations in kneejoint kinematics, neuromuscular control, and knee torque production in those with CAI. Most recently, Terada et al 12 demonstrated altered feed-forward patterns of the vastus medialis oblique (VMO) muscle in those with CAI.…”

“…Most recently, Terada et al 12 demonstrated altered feed-forward patterns of the vastus medialis oblique (VMO) muscle in those with CAI. The authors also found that participants with CAI had altered postlanding knee sagittal-plane kinematics.…”

“…More specifically, the CAI group demonstrated a decreased knee-flexion angle after landing during a stop-jump task. 12 A decreased knee-flexion angle negatively influences the energy-dissipation capability of the knee joint. Increased activation of the VMO may be a compensatory mechanism to allow greater energy dissipation at the knee during landing to protect the ankle joint.…”

Altered visual focus on sensorimotor control in people with chronic ankle instability

“…Sensorimotor mechanisms are largely responsible for maintaining joint homeostasis, including proper landing technique and dynamic stability (Riemann & Lephart, 2002). Although it has been reported that participants with CAI exhibit sensorimotor alterations during performance of dynamic stability tasks (Brown, Bowser, & Simpson, 2012;Caulfield & Garrett, 2002;Gribble & Robinson, 2009Hass, Bishop, Doidge, & Wikstrom, 2010;Terada, Pietrosimone, & Gribble, 2014), the underlying sensorimotor mechanisms associated with disability in CAI patients still remain unknown.…”