Elbow Swelling Differential Diagnoses and Management

Key Diagnostic Considerations

The American College of Radiology recommends plain radiographs as the first-line imaging to differentiate between infectious, inflammatory, traumatic, and neoplastic etiologies of elbow swelling, with the most critical distinction being septic arthritis versus other causes due to implications for urgent treatment 1
Septic arthritis is characterized by joint effusion with systemic signs of infection, requiring urgent aspiration and culture, as per the American College of Radiology guidelines 1, 2
Soft tissue infection/cellulitis is identified by effacement of fat planes and soft tissue swelling without intra-articular involvement, according to the American College of Radiology 2
Osteomyelitis presents with periosteal reaction and erosions in acute cases, and bone sclerosis in chronic cases, as noted by the American College of Radiology 1
Intra-articular loose bodies may cause mechanical symptoms with intermittent swelling, and must be excluded with initial imaging, as recommended by the American College of Radiology 7
Heterotopic ossification can present with swelling and limited range of motion, and should be considered in the differential diagnosis, according to the American College of Radiology 7
Tumors must be excluded with initial imaging, as per the American College of Radiology guidelines 1

Plain radiographs are mandatory first-line imaging to exclude fractures, tumors, intra-articular bodies, heterotopic ossification, osteochondral lesions, and soft tissue calcification, as recommended by the American College of Radiology 1, 7
Image-guided aspiration is essential when imaging cannot distinguish infected from noninfected fluid collections, and culture identifies the organism and directly affects treatment, according to the American College of Radiology 1, 2
CT with IV contrast can assess soft tissue extent and differentiate cellulitis, myositis, tenosynovitis, abscess, and septic arthritis, as noted by the American College of Radiology 2
MRI without IV contrast is appropriate for evaluating UCL injuries, lateral collateral complex injuries, and tendinous pathology, as recommended by the American College of Radiology 5
MRI or MR arthrography is used for loose bodies, osteochondral lesion stability, and synovial abnormalities, according to the American College of Radiology 7

Immediate arthrocentesis with culture is necessary for septic arthritis, followed by empiric antibiotics and potential surgical debridement, as per the American College of Radiology guidelines 1, 2
NSAIDs are recommended for pain relief in inflammatory conditions, along with rest and activity modification, as noted by Praxis Medical Insights 3, 6
Corticosteroid injections may be used for persistent symptoms despite first-line treatment, but with caution due to potential complications, as recommended by Praxis Medical Insights 3, 6
Compression wrap, semirigid supports, and progressive strengthening exercises are used in the management of traumatic injuries, according to Praxis Medical Insights 6
Surgical consultation is necessary for refractory cases or unstable fractures, as recommended by the American College of Radiology and Praxis Medical Insights 5, 6