What are the treatments for acromioclavicular (AC) osteoarthritis?

Treatment of Acromioclavicular (AC) Joint Osteoarthritis

Initial Conservative Management (6-12 Months)

Begin with a structured 6-12 month trial of conservative therapy before considering surgical intervention, as the majority of patients respond well to non-operative treatment. 1, 2, 3

Non-Pharmacological Interventions

• Exercise therapy focusing on strengthening the neck and shoulder muscles should be the cornerstone of treatment, though specific evidence for AC joint OA is limited and extrapolated from general OA guidelines 4, 5
• Activity modification to avoid exacerbating movements (particularly overhead activities and cross-body adduction) is recommended in all surgical case series 1, 2, 3
• Patient education about the condition helps counter misconceptions about inevitable progression 4
• Weight loss if overweight or obese reduces mechanical stress on the joint 4
• Local heat or cold applications may provide temporary symptomatic relief 4

Pharmacological Treatment Algorithm

First-Line:

• Oral NSAIDs at the lowest effective dose for the shortest duration are the primary pharmacological intervention, as topical NSAIDs are unlikely to penetrate adequately to the AC joint 1, 2, 3
• Consider gastroprotection with proton pump inhibitors, especially in elderly patients 4
• Assess cardiovascular, gastrointestinal, and renal risk factors before prescribing 4

Second-Line:

• Intra-articular corticosteroid injections into the AC joint show approximately 50% improvement in pain levels at mean 7.5-month follow-up 3
• This can serve both as a therapeutic intervention and diagnostic confirmation that the AC joint is the pain source 2, 3

Avoid:

• Acetaminophen is not specifically studied for AC joint OA and general OA guidelines show limited efficacy 4
• Glucosamine and chondroitin are not recommended based on lack of evidence 4

Defining Conservative Treatment Failure

Conservative management should be considered failed after 4-6 months of appropriate non-operative treatment (though the range in the literature is 3-12 months), when patients remain unable to return to their previous or desired activity levels despite compliance with therapy 1, 3, 5

Surgical Management

When conservative treatment fails, arthroscopic distal clavicle excision is the preferred surgical approach, offering equivalent functional outcomes to open techniques but with faster rehabilitation and less invasiveness 1, 3

Surgical Technique Considerations

• Excise 0.5-2 cm of the distal clavicle for optimal outcomes 3
• Both bursal and direct superior arthroscopic approaches yield good results 1
• Preserve the AC ligaments when possible to minimize post-operative instability 2
• Mean functional outcomes average 87.8% improvement at mean 28.5-month follow-up 3

Special Consideration for Concomitant Pathology

• In patients with combined rotator cuff tears and AC joint osteoarthritis, perform isolated rotator cuff repair with subacromial decompression first, as this approach shows equivalent outcomes to combined distal clavicle resection but with lower risk and cost 6
• Patients requiring concomitant shoulder procedures (such as rotator cuff repair) have similarly good outcomes when distal clavicle excision is added 3

Important Caveats

• No high-quality evidence exists comparing non-pharmacological interventions to surgical treatment for persistent AC joint OA 5
• The evidence base consists primarily of surgical case series rather than randomized controlled trials 3, 5
• Open versus arthroscopic distal clavicle excision shows no significant difference in outcomes, but arthroscopic approaches offer faster recovery and avoid deltotrapezial fascia violation 1, 3
• Recovery time averages 6 months for return to full activity after surgery 3