Dislocation

Instability

Osteoarthritis

Possible differential diagnosis of unilateral SCG swelling

• Mechanical enthesopathy - Overload syndromes - Trauma

• Inflammatory enthesitis - Peripheral spondyloarthritides (e.g. psoriatic arthritis, SAPHO syndrome, reactive arthritis) - Endocrinopathies (e.g. diabetes, hypothyroidism) - Crystalline arthropathies (e.g. gout, CPPD)

• Arthritis - Septic - Inflammatory rheumatic diseases (e.g. rheumatoid arthritis, peripheral spondyloarthritis) - Crystalline arthritis (e.g. gout, CPPD)

• Osteitis/ Osteomyelitis - Septic - Aseptic (e.g. SAPHO syndrome, CRMO) - Osteitis clavicularis condensans

• Subluxation - Traumatic with ligamentous lesions - Benign subluxation (mainly women, dominant side) - Articular hyperlaxity

• Arthrosis - primary (rare) - secondary (for all other mentioned diseases), with or without subluxation

Reference