CNO/CRMO may be on the same spectrum as SAPHO, but manifesting at a younger age range. They are currently considered as Autoinflammatory Syndromes, part of the wider Autoinflammatory Bone Disorders, but their genetic defects have not been elucidated.
They share clinical features with Ankylosing Spondylitis, DISH, Psoriatic Arthritis, Hidradenitis Suppurativa, Neutrophilic Dermatoses and Inflammatory Bowel Diseases. Bone and skin/mucosa appear to be the main target tissues.
The main diagnostic differentials are Infectious Osteomyelitis/Spondylodisciitis and Histiocytosis.
NSAIDs and steroids are the mainstay of treatment. Promising treatments include anti-resorptives (eg Bisphosphonates), anti-TNFs, anti-IL1 and anti-Th17.
Autoinflammatory bone disorders with special focus on chronic recurrent multifocal osteomyelitis (CRMO)