Is Sternoclavicular Joint Inflammation Called Costochondritis?
No, inflammation of the sternoclavicular (claviculosternal) joint is NOT classified as costochondritis and should be recognized as a distinct clinical entity. 1
Anatomical Definition and Clinical Distinction
The American Heart Association and American College of Cardiology explicitly define costochondritis as inflammation confined to:
- Costochondral junctions (where ribs meet costal cartilage)
- Chondrosternal joints (where costal cartilages meet the sternum)
- The sternoclavicular joint is specifically excluded from this definition 1
Mislabeling sternoclavicular joint inflammation as costochondritis may lead to missed diagnoses of serious underlying conditions that require different diagnostic workup and management strategies. 2
Why This Distinction Matters for Patient Outcomes
Different Disease Spectrum
When a patient presents with sternoclavicular joint swelling, tenderness, and inflammation, you must consider a broader and more serious differential diagnosis including:
- Spondyloarthritis – bone scintigraphy shows 100% sensitivity for detecting sternoclavicular joint inflammation in anterior chest wall pain, making this joint a key early indicator 2
- SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, osteitis) – CT findings show sclerosis in 77.3%, erosions in 44%, and hyperostosis in 41% of affected patients 2
- Septic arthritis – requires urgent antimicrobial therapy and possible surgical drainage 2
- Rheumatoid arthritis 2
- Neoplastic processes 2
- Sternocostoclavicular hyperostosis – a chronic inflammatory disorder causing sterile osteomyelitis of the sternum and medial clavicle, often associated with palmoplantar pustulosis 3
Diagnostic Approach for Sternoclavicular Joint Pathology
Initial imaging strategy:
- Bone scintigraphy demonstrates 100% sensitivity for detecting sternoclavicular joint inflammation and is highly valuable for early identification of spondyloarthritis-related involvement 2
- CT of the sternoclavicular region provides objective criteria showing characteristic osseous changes (sclerosis, erosions, hyperostosis) particularly useful for diagnosing SAPHO syndrome 2
- Plain radiographs may show symmetric hyperostosis of the sternal portions of the clavicles, synostosis of the sternoclavicular joints, and thickened sternum 4
Clinical evaluation should localize tenderness precisely:
- Sternoclavicular joint pathology presents with tenderness and possible swelling at the clavicle-sternum articulation 1
- This is anatomically distinct from costochondritis, which shows tenderness at costochondral or chondrosternal junctions (most commonly ribs 2-7) 1
Common Pitfall to Avoid
Do not assume sternoclavicular joint inflammation is benign musculoskeletal pain. The European consensus on chronic non-bacterial osteitis (2025) lists Tietze syndrome as a separate differential diagnosis from sternoclavicular pathology, reinforcing the need to treat these entities independently. 2 Greater awareness is needed because low recognition of sternoclavicular pathology leads to diagnostic delays, resulting in significant morbidity, psychological burden, restricted mobility, and secondary degenerative joint changes. 3
Treatment Implications
Unlike costochondritis (which responds to NSAIDs, ice/heat, and reassurance 5, 6), sternoclavicular joint inflammation may require:
- Systemic disease-modifying therapy for spondyloarthritis or rheumatoid arthritis 2
- Intravenous bisphosphonates or TNF-alpha inhibitors for sternocostoclavicular hyperostosis 3
- Antimicrobial therapy and surgical debridement for infectious causes 7
- Antituberculous therapy for tubercular involvement 8
The standard costochondritis treatment approach (NSAIDs for 1-2 weeks, local ice/heat, low-dose colchicine for refractory cases) is insufficient for sternoclavicular joint pathology. 5