What is the treatment for a fifth metacarpal (pinky) fracture?

Treatment of Fifth Metacarpal (Pinky) Fracture

Fifth metacarpal fractures should be treated based on displacement, with non-displaced or minimally displaced fractures (<2mm) managed conservatively with buddy taping or ulnar gutter splint, while fractures with >2mm displacement may require surgical intervention with intramedullary K-wire fixation. 1

Assessment and Classification

• Evaluate fracture displacement:

  • <2mm displacement: Conservative management
  • 2-4mm displacement: Consider closed reduction under anesthesia

  • 4mm displacement: Potential surgical intervention 1

• Additional factors to consider:

  • Patient age and activity level
  • Functional demands
  • Presence of rotation or angulation (>45° angulation often requires intervention) 2

Conservative Management

For non-displaced or minimally displaced fractures:

1. Immobilization options:

   • Ulnar gutter splint (simple and proven method for boxer's fractures) 3
   • Buddy taping to adjacent finger
   • Soft wrap without reduction (research shows cast immobilization is not superior to soft wrap for most boxer's fractures) 4

2. Duration of immobilization:

   • Typically 3-6 weeks until radiographic evidence of healing
   • Early protected motion is critical to prevent stiffness 1

3. Rehabilitation protocol:

   • Begin with protected motion and pain control
   • Progress to gentle passive range of motion exercises at approximately 4 weeks
   • Advance to active-assisted range of motion as tolerated
   • Implement strengthening exercises after fracture healing is evident 1

Surgical Management

For displaced fractures (>2mm), unstable fractures, or those with rotational deformity:

1. Indications for surgery:

   • Failed closed reduction (displacement >3mm persists)
   • Unstable fracture after reduction
   • Evidence of neurovascular compromise
   • Significant rotational deformity 1

2. Surgical options:

   • Intramedullary K-wire fixation (reference technique with better mobility outcomes)
   • Locking plate fixation (alternative but with potentially poorer mobility outcomes) 2

3. Post-surgical care:

   • Follow-up at 2-week intervals initially
   • Monitor for complications such as wire migration, neurologic lesions, or stiffness
   • Implement rehabilitation protocol as described above 1, 2

Follow-up and Monitoring

• Regular clinical and radiographic follow-up at 2-week intervals initially
• Continue monitoring for at least 6 months
• Assess:
  • Pain levels
  • Range of motion progress
  • Fracture healing
  • Functional improvement 1

Potential Complications and Pitfalls

• Failure to verify reduction within 7-14 days can lead to malunions requiring surgical correction
• Neglecting early motion therapy can result in joint stiffness and poor functional outcomes
• Complications of K-wire fixation include wire migration and neurologic lesions
• Complications of plate fixation include stiffness, head necrosis, and delayed consolidation 1, 2

Special Considerations

• For office workers and those with high functional demands, antegrade intramedullary K-wire fixation may allow earlier return to work (average 3.9 days vs. 33.6 days with conservative treatment) 5
• Elderly patients with fragility fractures should be evaluated for osteoporosis and fall prevention strategies 6, 1
• Consider calcium (1000-1200 mg/day) and vitamin D (800 IU/day) supplementation for patients over 50 years 1