Role of proprioceptors in chronic musculoskeletal pain.

NEW FINDINGS: What is the topic of this review? Why proprioceptors, which are non-nociceptive, low-threshold mechanosensory neurons that monitor muscle contraction and body position, express several proton-sensing ion channels and receptors. What advances does it highlight? ASIC3 is a dual function protein for proton-sensing and mechano-sensing in proprioceptors that can be activated by eccentric muscle contraction or lactic acidosis. A role is proposed for proprioceptors in non-nociceptive unpleasantness (or sng), which is associated with their acid-sensing properties, in chronic musculoskeletal pain.

ABSTRACT: Proprioceptors are non-nociceptive low-threshold mechanoreceptors. However, recent studies have shown that proprioceptors are acid-sensitive and express a variety of proton-sensing ion channels and receptors. Accordingly, although proprioceptors are commonly known as mechanosensing neurons that monitor muscle contraction status and body position, they may have a role in the development of pain associated with tissue acidosis. In clinical practice, proprioception training is beneficial for pain relief. Here we summarize the current evidence to sketch a different role of proprioceptors in 'non-nociceptive pain' with a focus on their acid-sensing properties.