More than movement: the proprioceptive system as a new regulator of musculoskeletal biology

The proprioceptive system is essential for the control of coordinated movement and posture. Thus, traditionally, the study of proprioception has focused on its role in motor control. In this review, we present more recent findings on other, non-traditional functions of this system. We focus on its involvement in musculoskeletal development, function and pathology, including the regulation of spinal alignment, bone fracture repair and joint morphogenesis. We present the hypothesis that the proprioceptive system plays a central role in musculoskeletal biology, and that understanding the underlying molecular mechanisms will promote both basic science and medical innovations. As an example, we discuss recent evidence indicating that Piezo2, a key mechanosensitive ion channel of proprioception, regulates spine alignment and joint development. The presented findings show that the proprioceptive system regulates a wide range of developmental and physiological processes and that its dysfunction may contribute to the etiology of various musculoskeletal pathologies.