Does a positive fifth metatarsal (5th metatarsal) proximal phalanx fracture require a splint or postoperative (postop) shoe?

Management of Fifth Metatarsal Proximal Phalanx Fractures

A fifth metatarsal proximal phalanx fracture should be treated with a hard-soled shoe or controlled ankle motion (CAM) walker boot rather than a splint for optimal healing and functional outcomes.

Diagnostic Approach

• Radiographs are the initial imaging study of choice for suspected fifth metatarsal fractures
• Standard three views should be obtained: anteroposterior, lateral, and mortise views 1
• MRI may be considered if radiographs are negative but clinical suspicion remains high 1

Treatment Options

Hard-Soled Shoe vs. CAM Walker Boot

• Both treatment options provide adequate immobilization and lead to successful healing 2
• CAM walker boot may result in slightly faster bone healing (7.2 weeks vs 8.6 weeks) 2
• However, time to return to prior activity levels is similar between both treatment options (8.3 weeks for CAM boot vs 9.7 weeks for hard-soled shoe) 2
• Clinical and functional outcomes are comparable between both treatment methods 2

Treatment Duration

• Treatment typically requires 4-6 weeks of immobilization 3
• For fifth metatarsal tuberosity avulsion fractures:
  • Initial treatment with compressive dressing
  • Transition to short leg walking boot for approximately 2 weeks
  • Progressive mobility as tolerated after initial immobilization 3

When Splinting is Appropriate

• Splinting is generally reserved for:
  • Initial emergency management before definitive treatment
  • Cases with significant displacement that cannot be corrected by closed reduction 4
  • When a rigid splint is needed to prevent further injury during transport to a medical facility 5

Treatment Algorithm

1. Confirm diagnosis with standard radiographic views
2. Assess fracture displacement (if >2mm displacement, consider surgical consultation)
3. For non-displaced or minimally displaced fractures:
   • Provide initial pain management
   • Choose either hard-soled shoe or CAM walker boot based on:
     • Patient comfort and compliance
     • Activity level and occupation
     • Fracture location and stability
4. Follow up at 2-3 weeks to assess healing
5. Continue immobilization for 4-6 weeks total
6. Progressive return to normal footwear and activities

Common Pitfalls and Considerations

• Failure to distinguish between different types of fifth metatarsal fractures (tuberosity avulsion vs Jones fracture)
• Jones fractures (at the metaphyseal-diaphyseal junction) have higher risk of nonunion and require longer immobilization (6-8 weeks) 3
• Inadequate immobilization may lead to delayed union or nonunion
• Excessive immobilization can lead to joint stiffness and muscle atrophy
• Regular follow-up with repeat radiographs is essential to ensure proper healing

By following this evidence-based approach, most fifth metatarsal proximal phalanx fractures will heal successfully with conservative management using either a hard-soled shoe or CAM walker boot, avoiding the need for surgical intervention while optimizing functional outcomes.