Is a walking boot sufficient to treat a 4th metatarsal fracture?

Management of 4th Metatarsal Fractures with Walking Boots

A walking boot is sufficient for treating most 4th metatarsal fractures, providing adequate immobilization and protection while allowing for functional mobility during the healing process. The evidence supports using a controlled ankle motion (CAM) walker boot as the preferred treatment option for these fractures.

Diagnostic Considerations

Before determining treatment approach:

• Ensure proper diagnosis with standard radiographic views (anteroposterior, lateral, and mortise) 1
• Rule out displacement that would require surgical intervention
• Consider location of fracture (shaft vs. proximal)

Treatment Algorithm for 4th Metatarsal Fractures

For Non-displaced or Minimally Displaced Fractures:

1. Initial Management:

   • CAM walker boot immobilization
   • Non-weight bearing for first 1-3 weeks (depending on pain and fracture characteristics)
   • Transition to weight bearing as tolerated while continuing boot use

2. Duration of Immobilization:

   • Total immobilization period: 4-6 weeks for shaft fractures 2, 3
   • Proximal 4th metatarsal fractures may require longer immobilization (6-8 weeks) similar to proximal 5th metatarsal fractures 4

3. Follow-up Protocol:

   • Radiographic assessment at 4 weeks to confirm healing progression
   • Continue boot until clinical and radiographic healing evident

For Displaced Fractures:

• Fractures with significant displacement (>2mm) may require surgical intervention 2
• Consult orthopedic specialist for evaluation

Evidence Supporting Walking Boot Use

Research demonstrates that CAM walker boots are superior to other conservative treatment options:

• CAM walker boots significantly reduce peak pressure at the metatarsal region compared to postoperative sandals and athletic shoes 5
• Walking boots provide better contact pressure distribution during common gait activities 5
• Controlled studies show faster bone healing with CAM walker boots compared to hard-soled shoes (7.2 vs 8.6 weeks) 6

Special Considerations for Proximal 4th Metatarsal Fractures

Proximal 4th metatarsal fractures deserve special attention as they:

• May behave similarly to proximal 5th metatarsal fractures 4
• Often require longer healing time than more distal metatarsal fractures
• May benefit from more stringent non-weight bearing periods (3 weeks non-weight bearing followed by 3+ weeks of weight bearing immobilization) 4

Potential Pitfalls and Complications

• Inadequate Immobilization: Insufficient immobilization time may lead to delayed union or non-union
• Premature Weight Bearing: Returning to full weight bearing too early can disrupt healing
• Overlooking Proximal Fractures: Proximal 4th metatarsal fractures require longer immobilization periods than shaft fractures
• Patient Compliance: Ensure patient understands the importance of following weight bearing restrictions and proper boot use

By following this evidence-based approach, most 4th metatarsal fractures can be effectively treated with a walking boot, avoiding unnecessary surgical intervention while promoting optimal healing and functional recovery.