Decoupling of laxity and cortical activation in functionally unstable ankles during joint loading

Eur J Appl Physiol. 2014 Oct;114(10):2129-38. doi: 10.1007/s00421-014-2929-3. Epub 2014 Jun 24.

Abstract

Purpose: Recent studies have highlighted central nervous system alterations following ligamentous injury that may contribute to joint instability. However, research has not observed cortical responses to joint loading or sensory changes in the context of joint laxity following injury.

Methods: Forty-two subjects were stratified into healthy (CON), unstable (UNS), and coper (COP) groups using ankle injury and instability history. Event-related desynchronization (%) from electroencephalography quantified somatosensory cortex activity as the ankle was loaded using an arthrometer.

Results: Cortical activation increased as the ankle was loaded (F = 63.05, p < 0.001), but did not differ between groups (F = 1.387, p = 0.268), despite greater laxity in UNS (F = 3.58, p = 0.038).

Conclusions: Increased somatosensory cortex activity was observed with joint loading; however, though UNS demonstrated a degree of mechanical instability, no differences in magnitude of cortical activation were observed. Continued research should explore how the relationship between cortical activation and joint stiffness is affected following ligamentous injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Ankle Joint / innervation
  • Ankle Joint / physiopathology*
  • Case-Control Studies
  • Exercise
  • Female
  • Humans
  • Joint Instability / physiopathology*
  • Male
  • Somatosensory Cortex / physiology*