Can weight-bearing be initiated at 8 weeks with a proximal humerus fracture?

Weight-Bearing After Proximal Humerus Fracture at 8 Weeks

Weight-bearing activities can be safely initiated at 8 weeks following a proximal humerus fracture, as this timeframe allows for adequate bone healing and reduces the risk of displacement or complications. 1

Rehabilitation Timeline for Proximal Humerus Fractures

Early Phase (0-6 weeks)

• Immobilization: Use of a sling is recommended initially (86% of surgeons advise this) 1
• Early mobilization: Begin with gentle pendulum exercises and passive range of motion within the first few days post-injury/surgery 2
• Protected movement: Active-assisted range of motion typically starts around 3 weeks 2
• Non-weight bearing: Most protocols recommend avoiding weight-bearing activities during this period 2

Intermediate Phase (6-8 weeks)

• Transition period: This is when most clinicians begin to introduce weight-bearing activities
• Load progression: 53.4% of surgeons recommend initiating load-bearing after 6 weeks for conservatively treated patients, and 59.8% for operatively treated patients 1
• Range of motion: Unlimited ROM is typically allowed at 4-6 weeks post-fracture 2

Advanced Phase (8+ weeks)

• Weight-bearing activities: Can be safely initiated at 8 weeks
• Strengthening exercises: Typically begin at 6 weeks and progress gradually 2
• Return to function: Complete removal of restrictions often occurs around 6 weeks, with progressive loading thereafter 2

Evidence Supporting Weight-Bearing at 8 Weeks

The current evidence suggests that initiating weight-bearing at 8 weeks is appropriate for several reasons:

1. Bone healing timeline: Proximal humerus fractures typically show significant healing by 6-8 weeks, making this a reasonable timeframe to begin weight-bearing activities 3

2. Survey data: A recent Dutch survey found that most surgeons (>50%) recommend starting load-bearing activities after 6 weeks, suggesting that 8 weeks provides an additional safety margin 1

3. Emerging evidence: Recent research indicates that early weight-bearing (EWB) protocols may be feasible, safe, and effective for humeral fractures, though specific protocols vary 4

Considerations for Weight-Bearing Progression

• Fracture type: More complex fractures (e.g., 3-part or 4-part) may require more cautious progression 5
• Treatment method: Operatively treated fractures may have different weight-bearing timelines than non-operatively treated ones 1
• Bone quality: Patients with osteoporosis or poor bone quality may require more gradual weight-bearing progression 3

Potential Pitfalls and Caveats

• Excessive early loading: One study reported unsatisfactory outcomes in two patients who engaged in excessive post-operative early weight-bearing 4
• Lack of standardization: There is substantial variability in rehabilitation protocols for proximal humerus fractures, with limited consensus on optimal timing for weight-bearing 2
• Individual variation: While 8 weeks is generally safe, radiographic confirmation of adequate healing should guide the decision to begin weight-bearing activities

Monitoring During Weight-Bearing Progression

• Perform radiographic evaluation at 6 weeks, 3 months, 6 months, and 1 year to assess fracture healing and implant position 6
• Monitor for signs of pain, swelling, or decreased function during weight-bearing progression, which may indicate complications
• Assess functional recovery using validated outcome measures to determine the effectiveness of rehabilitation 6

By initiating weight-bearing at 8 weeks post-fracture, patients can safely progress toward functional recovery while minimizing the risk of complications such as non-union or implant failure.