What is the treatment for AC (acromioclavicular) joint swelling?

Treatment of AC Joint Swelling

For AC joint swelling, initiate treatment with ice application, rest, and intra-articular corticosteroid injection after joint aspiration to confirm the diagnosis and provide immediate relief. 1, 2

Initial Diagnostic Approach

• Obtain plain radiographs first to evaluate for fracture, arthritis, or bony abnormalities, as this provides essential baseline information and helps exclude other pathology 1
• Perform joint aspiration under image guidance (ultrasound or fluoroscopy) to differentiate inflammatory arthritis from infection, crystal disease, or cyst formation 1, 2
• Consider MRI if diagnosis remains unclear after initial workup, particularly to evaluate for underlying rotator cuff pathology, AC joint cysts (associated with massive rotator cuff tears), or other soft tissue abnormalities 3, 4, 5

First-Line Treatment Strategy

Non-pharmacological interventions should be implemented immediately:

• Apply ice or cool packs to the affected joint for symptomatic relief 1, 2
• Temporary rest of the joint while maintaining gentle range of motion to prevent stiffness 1, 2

Intra-articular corticosteroid injection is the optimal first-line treatment:

• Joint aspiration followed by long-acting glucocorticosteroid injection is highly effective and safe for monoarticular inflammatory arthritis 1, 2
• This approach alone may be sufficient for many patients without requiring systemic therapy 1, 2

Systemic Treatment Options

If intra-articular injection is not feasible or insufficient:

• NSAIDs with gastroprotection (proton pump inhibitor or H2 blocker) are effective, particularly in patients under 65 years without cardiovascular or renal contraindications 1, 2, 6
• Low-dose oral colchicine (0.5 mg up to 3-4 times daily) is an alternative, though use is limited by gastrointestinal side effects and comorbidities in older patients 1, 2
• Short tapering course of oral corticosteroids (or parenteral corticosteroids) for patients with contraindications to NSAIDs or colchicine 1, 2

Special Considerations Based on Underlying Pathology

AC joint cysts (associated with rotator cuff tears):

• These present as painless swelling and require MRI for diagnosis 3, 4, 5
• Aspiration alone results in recurrence; definitive treatment requires cyst excision with or without AC joint resection and rotator cuff repair 3, 4
• Consider arthroscopic debridement with open cyst excision and AC joint capsule closure 4

Septic arthritis (if suspected):

• Image-guided aspiration with culture is mandatory before initiating antibiotics 1
• Ultrasound or CT guidance ensures accurate needle placement and reduces contamination risk 1

Crystal arthropathy (calcium pyrophosphate deposition):

• Treatment follows the algorithm above, with joint aspiration confirming CPP crystals 1, 2
• Prophylaxis with low-dose colchicine (0.5-1 mg daily) or NSAIDs prevents recurrent attacks 1, 2

Critical Pitfalls to Avoid

• Do not use intravenous colchicine due to high risk of serious toxicity 2
• Assess renal function, cardiovascular risk, and GI bleeding risk before prescribing NSAIDs, especially in elderly patients 6
• Avoid peri-tendon injections around the AC joint that could compromise rotator cuff integrity 1
• Do not ignore underlying rotator cuff pathology when AC joint cysts are present, as this leads to recurrence 3, 4
• Consider age and comorbidities carefully, as AC joint swelling often affects older patients with multiple risk factors for medication complications 1, 2, 6

Monitoring and Follow-up

• Reassess within 1-2 weeks after initial treatment to evaluate response 1
• If swelling persists or recurs, obtain MRI to evaluate for structural pathology requiring surgical intervention 3, 4
• For chronic or recurrent inflammation, consider disease-modifying therapy consultation with rheumatology 1