Sternocostoclavicular Hyperostosis: A Review

Abstract

Sternocostoclavicular hyperostosis (SCCH) is a chronic inflammatory disorder which presents with erythema, swelling, and pain of the sternoclavicular joint. Approximately one half of patients have acne or pustular lesions with the best described association being with palmoplantar pustulosis (PPP). Extrasternal articular disease occurs in about a quarter of patients. The inflammatory process spans several years and has periods of exacerbation followed by remission. The histologic picture demonstrates a sterile osteomyelitis of the sternum and medial end of the clavicle. The diagnosis of SCCH is confirmed radiographically by hyperostosis and sclerosis of the sternum with involvement of the first rib on computed tomography (CT). The focal uptake of radiopharmaceutical on bone scintigraphy called the ‘bullhead’ sign is highly sensitive of SCCH. Treatment is aimed at easing pain and modifying the inflammatory process. Evidence over the last two decades suggests a role for intravenous bisphosphonates and tumor necrosis factor alpha inhibitors. A low level of awareness of SCCH often leads to a delay in diagnosis. This translates into significant morbidity and brings a psychological burden. Untreated chronic inflammation of the sternoclavicular joint leads to restricted mobility and secondary degenerative joint changes. In the search for a diagnosis, patients often undergo multiple serologic and imaging studies and in the experience of the author are referred to multiple specialists before a correct diagnosis is made. Greater awareness of SCCH is needed to prevent the irreversible physical and psychological impairments associated with the disease.