What rehabilitation program is recommended for a young to middle-aged adult patient with an acromioclavicular (AC) joint injury type 3, 7 weeks post-injury, who has already completed initial physical therapy for range of motion exercises and isometric with light strengthening exercises?

Week 7 Post-Injury AC Joint Type 3 Rehabilitation Program

Primary Recommendation

At 7 weeks post-injury for a Type 3 AC joint injury, advance to progressive isotonic strengthening with a mixed program of closed and open kinetic chain exercises, combined with neuromuscular control training and early plyometric preparation, while monitoring for pain and joint reaction. While the provided evidence focuses primarily on ACL reconstruction rather than AC joint injuries, the principles of progressive strengthening, neuromuscular control, and functional training apply to upper extremity rehabilitation.

Phase Classification

At 7 weeks, you are transitioning from the early protection phase into the intermediate strengthening phase for AC joint rehabilitation. The patient has completed initial range of motion and light isometric work, indicating readiness for progressive loading 1.

Progressive Strengthening Protocol

Isotonic Strengthening Program

• Implement a mixed isotonic program targeting the deltoid, rotator cuff, scapular stabilizers, and trapezius muscles, as combined programs achieve superior strength outcomes and reduce atrophy compared to single-modality approaches 1.

• Begin with closed kinetic chain exercises including:

  • Wall push-ups with progressive hand elevation
  • Quadruped position exercises (bear crawls, planks with arm reaches)
  • Weight-bearing through the affected arm in controlled positions
  • These exercises can be performed safely at this stage as they provide joint compression and stability 1.

• Progress to open kinetic chain exercises in pain-free ranges:

  • Shoulder flexion and abduction with resistance bands or light dumbbells (1-3 lbs initially)
  • External and internal rotation exercises
  • Scapular retraction and protraction with resistance
  • Start in restricted ranges (avoiding end-range overhead positions initially) and progress weekly based on tolerance 1.

Eccentric Training Integration

• Add eccentric training components as they improve functional outcomes and prepare for return to activity 1.
• Perform slow, controlled lowering phases (3-5 seconds) during all strengthening exercises.
• Eccentric training can be safely initiated at this phase without adverse effects on joint stability 1.

Neuromuscular Control and Proprioception

Motor Control Training

• Implement motor control exercises including unstable surface training, as this significantly improves joint proprioception during intermediate phases 1, 2.

• Specific exercises include:

  • Single-arm support on unstable surfaces (foam pads, balance discs)
  • Rhythmic stabilization drills with therapist perturbations
  • Closed-chain weight shifts on unstable surfaces
  • Ball stabilization exercises against a wall
  • These exercises improve proprioception without additional benefit to strength alone, so they must be combined with strengthening 1.

Scapular Control Emphasis

• Focus on scapular stabilization exercises as altered scapular mechanics persist after AC joint injuries and require specific motor control work 2, 3.
• Include exercises targeting serratus anterior, lower trapezius, and rhomboids.
• Monitor scapular winging and dyskinesis patterns during all exercises.

Core Stability Integration

• Add core stability exercises to improve overall shoulder girdle function and movement quality, as these improve functional outcomes when added to conventional rehabilitation 1, 2.

• Implement a 4-week core stability program including:

  • Planks with arm reaches
  • Anti-rotation exercises (Pallof press variations)
  • Dead bugs and bird dogs
  • These exercises improve movement patterns and functional performance 2.

Early Plyometric Preparation

• Begin preparatory plyometric activities at low intensity, as the combination of eccentric and plyometric training shows superior outcomes for balance and functional activities 1.

• Start with:

  • Two-hand ball catches and throws against a wall
  • Light medicine ball (1-2 kg) chest passes
  • Gradual progression to single-arm activities over the next 2-4 weeks
  • These activities prepare the joint for higher-level demands while maintaining controlled loading 1.

Exercise Dosing and Progression

Training Frequency and Volume

• Perform strengthening exercises 3-4 times per week with at least 48 hours between sessions targeting the same muscle groups.
• Each session should include 3-4 exercises per muscle group, 3 sets of 10-15 repetitions 2.
• Neuromuscular control exercises can be performed daily as they involve lower loads 1.

Load Progression Criteria

• Progress resistance when the patient can complete 3 sets of 15 repetitions without pain, effusion, or increased joint temperature 1, 4.
• Increase load by 5-10% increments weekly if tolerated.
• Critical warning: If pain or joint reaction occurs, immediately reduce load and volume 4.

Monitoring and Red Flags

Session-to-Session Assessment

• Assess for pain, swelling, or warmth before each session as these indicate excessive loading requiring immediate modification 4.
• Monitor AC joint stability with palpation and stress testing weekly.
• Any increase in joint separation or pain with stress testing requires immediate physician consultation 4.

Functional Milestones

By week 10-12, the patient should demonstrate:

• Pain-free active range of motion in all planes
• Strength at least 70% of the contralateral side in major muscle groups
• Ability to perform functional activities (lifting objects to shoulder height, pushing/pulling) without compensation patterns 1, 5.

Common Pitfalls to Avoid

• Do not progress exercises if joint effusion or increased pain develops - this is the most critical error and leads to prolonged symptoms 4.
• Avoid neglecting scapular stabilization - this is a primary determinant of long-term shoulder function 2, 3.
• Do not rely solely on time-based progression - use criterion-based advancement with objective strength and functional testing 1, 2.
• Avoid isolated strengthening without neuromuscular control work - both must be combined as neither can replace the other for optimal recovery 2, 3.

Psychological Considerations

• Evaluate psychological factors including fear of reinjury and self-efficacy using objective instruments, as these influence rehabilitation progress 1, 3.
• Discuss realistic timelines - full return to overhead sports typically requires 12-16 weeks minimum, and patient expectations should be managed accordingly 1, 3.

Transition Criteria to Advanced Phase

Progress to advanced rehabilitation (weeks 10-12+) when the patient demonstrates:

• Full pain-free active range of motion
• Strength ≥80% of contralateral side
• No pain or joint reaction with current exercise program
• Successful completion of neuromuscular control exercises without compensation
• Psychological readiness for higher-level activities 1, 2.