Neuroimmune interactions in musculoskeletal conditions. An introduction for clinicians

BACKGROUND: The immune system protects against invading pathogens and helps maintain homeostasis. Other pivotal roles include the regulation of tissue health through interactions with the nervous system. Understanding how these neuroimmune interactions may go awry in musculoskeletal conditions and how they can be targeted therapeutically may optimise patient care.

METHODS: We conducted a clinically focused narrative review of the role of the immune and nervous systems in musculoskeletal health and conditions such as neck pain, back pain and osteoarthritis and how psychosocial and behavioural factors impact these conditions via interacting with neuroimmune functioning.

RESULTS: The interplay between the immune and nervous system is involved in both the physiology and pathology of musculoskeletal tissues, including bone, joint, nerve, muscle and tendon. We describe this at the local tissue, whole nervous system, and systemic (blood) level and how psychosocial and behavioural factors impact immune activity and influence outcomes. We also highlight recent advances in medical imaging and multi-omics that shed new light on the interplay between the immune and nervous systems in musculoskeletal conditions. Advances in understanding these relationships provide promising new treatment avenues for musculoskeletal conditions and important insights into how psychosocial- and behavioural-based therapies such as exercise and cognitive behavioural therapy work and can be optimised to improve outcomes.

CONCLUSIONS: This review provides clinicians with a foundation in the neuroimmunology of musculoskeletal conditions. It also explores how the immune and nervous systems, and their interplay can be modulated to improve prevention and management strategies.