What is the treatment for a Grade 1 Acromioclavicular (AC) joint separation?

Treatment of Grade 1 AC Joint Separation

Grade 1 AC joint separations should be managed conservatively with a structured rehabilitation program including initial rest, ice, NSAIDs for pain control, followed by progressive range of motion and strengthening exercises, with expected full return to activity within 1-2 weeks. 1, 2

Initial Management (First 3-7 Days)

Conservative treatment is the standard of care for Grade 1 AC joint injuries, which involve mild sprain of the acromioclavicular ligaments without displacement. 1, 2, 3

Immediate Interventions

• Apply ice to the affected shoulder for 15-20 minutes every 2-3 hours during the acute phase to reduce pain and swelling 1, 2
• Use a sling for comfort only during the first 3-7 days, but avoid prolonged immobilization beyond this period to prevent stiffness 1, 2
• Initiate NSAIDs (such as ibuprofen or naproxen) at the lowest effective dose for pain management and anti-inflammatory effect 1, 2

Activity Modification

• Avoid overhead activities, heavy lifting, and contact sports during the acute pain phase 1, 2
• Encourage gentle active range of motion within pain-free limits starting from day 1-3 to prevent shoulder stiffness 1, 2

Rehabilitation Protocol (Week 1-4)

Phase 1: Range of Motion (Days 1-7)

• Begin pendulum exercises and passive range of motion exercises as soon as pain allows, typically within 24-48 hours 1, 2
• Progress to active-assisted range of motion exercises in all planes (flexion, abduction, internal/external rotation) by day 3-5 1, 2
• Discontinue sling use once pain subsides, typically by day 3-7 1, 2

Phase 2: Strengthening (Week 2-4)

• Initiate isometric strengthening exercises for the rotator cuff and scapular stabilizers once full pain-free range of motion is achieved 1, 2
• Progress to resistance band exercises focusing on external rotation, internal rotation, and scapular retraction 1, 2
• Incorporate closed-chain exercises such as wall push-ups and planks to restore scapular control 1, 2

Phase 3: Return to Activity (Week 3-4)

• Advance to sport-specific or work-specific activities once full range of motion and at least 80% strength compared to the uninjured side is achieved 1, 2
• Most Grade 1 AC joint separations allow return to full activity within 1-2 weeks with appropriate rehabilitation 1, 2, 3

Imaging Considerations

Initial radiographic evaluation should include anteroposterior views in internal and external rotation and an axillary or scapula-Y view to confirm the diagnosis and rule out fracture or higher-grade separation. 4

• Plain radiographs are the preferred initial imaging modality for acute shoulder pain following trauma 4
• Upright radiographs are preferred over supine views as malalignment can be underrepresented on supine films 4
• Advanced imaging (MRI or CT) is not indicated for Grade 1 AC joint separations unless there is concern for concomitant rotator cuff injury or other soft tissue pathology 4

Follow-Up and Monitoring

• Reassess patients at 1-2 weeks to evaluate pain control, range of motion, and functional progress 1, 2
• If symptoms persist beyond 2-4 weeks despite appropriate conservative management, consider re-evaluation for possible higher-grade injury or concomitant pathology 1, 2

Critical Pitfalls to Avoid

Do not overlook the potential for long-term sequelae even with Grade 1 injuries, as studies show that up to 27% of patients with Grade I-II AC joint sprains may develop chronic AC joint pathology requiring subsequent intervention. 5

• Avoid prolonged immobilization beyond 7 days, as this increases risk of shoulder stiffness and delayed recovery 1, 2
• Do not assume all "Grade 1" injuries will have benign outcomes—radiographic degenerative changes can develop in a significant proportion of patients over time 5
• Ensure adequate rehabilitation of scapular stabilizers and rotator cuff, as failure to address these can lead to persistent symptoms 1, 2
• Do not rush return to contact sports or overhead activities before achieving full pain-free range of motion and adequate strength, as premature return increases risk of re-injury 1, 2, 3

When to Consider Surgical Referral

Surgery is not indicated for Grade 1 AC joint separations. 1, 2, 3

• If symptoms persist beyond 3-6 months despite appropriate conservative management, consider referral to an orthopedic specialist to evaluate for chronic AC joint instability or other pathology 1, 2