Dysregulation of Mechanosensory Circuits Coordinating the Actions of Antagonist Motor Pools Following Peripheral Nerve Injury and Muscle Reinnervation

After peripheral nerve damage, the body can regenerate nerves to re-establish connections between the central nervous system and muscles. However, this regeneration doesn't always restore normal movement control. This study investigates how nerve injury and muscle reinnervation affect spinal reflex pathways that coordinate antagonist muscles (muscles that oppose each other) at the ankle joint in rats. The findings suggest extensive dysregulation in the spinal cord circuits responsible for coordinating reflex activation of agonist and antagonist muscles.

• 1
  Stretch applied to reinnervated antagonists produced much greater than normal levels in both suppression and facilitation of agonist muscle activity.
• 2
  There was a reversal in the normal dominance in occurrence of suppression over facilitation.
• 3
  The findings indicate severe dysregulation in mechanosensory reflex coordination of agonist and antagonist muscles following peripheral nerve injury and muscle reinnervation in rats.