Cutaneous afferent feedback from the posterior ankle contributes to proprioception

Area of Science:

• Neuroscience
• Biomechanics
• Kinesiology

Background:

• Cutaneous mechanoreceptors detect skin strain from joint movement, contributing to proprioception.
• The role of posterior ankle skin feedback in proprioception during passive movement is not fully understood.

Purpose of the Study:

• To investigate the contribution of posterior ankle skin feedback to position sense during passive ankle movements.
• To assess how reduced skin feedback affects the perception of ankle joint position.

Main Methods:

• 28 healthy adults participated, with 14 receiving topical anesthesia and 14 a placebo on their posterior ankle skin.
• Position sense was evaluated using a passive joint matching task before and after cream application.
• Ankle position sense was assessed at target angles of 6°, 12°, and 18° in both dorsiflexion and plantar flexion.

Main Results:

• Anesthesia of posterior ankle skin led to a perceived alignment when the ankle was more dorsiflexed, indicating skin stretch is a key signal.
• Increased dorsiflexion was needed to compensate for reduced skin feedback, suggesting intact skin and muscle stretch are important.
• Reduced skin feedback increased variability in matching tasks during larger ankle movements.

Conclusions:

• Posterior ankle skin feedback significantly contributes to position sense during passive ankle movements.
• Reduced peripheral skin sensitivity, as seen in aging or neurological disorders, may impair proprioception.
• Ankle skin sensitivity is a critical factor for maintaining accurate joint position awareness.