Sympathosensory interactions - Possible relevance in osteoarthritis.

The role of the sympathetic and sensory nervous systems in the development and progression of osteoarthritis (OA) is widely recognized, as is the fact that these systems can influence each other. However, the nature of sympathosensory interactions during OA progression remains unclear. In this narrative review, we provide an overview of scientifically proven or putative sympathosensory interactions at the peripheral, spinal, and central levels. We highlight the factors that determine direct or indirect coupling types and describe the signaling and cross-signaling mechanisms of interaction at these different peripheral and central levels. Additionally, we discuss the clinical relevance of possible sympathosensory interactions in OA by introducing a new biopsychosocial OA model emphasizing the vicious cycle of chronic local and systemic inflammation, chronic pain, sleep deprivation, and chronic stress. These interrelated processes also underlie and contribute to common comorbidities such as hypertension and obesity and are unified by a state of autonomic imbalance marked by sympathetic dominance.