Treatment of Fifth Proximal Phalanx Fracture
For uncomplicated fifth proximal phalanx fractures with minimal angulation (<10 degrees), buddy taping to the adjacent finger is the primary treatment, while fractures with greater angulation, displacement, or malrotation require closed reduction or surgical fixation. 1
Initial Assessment
Obtain anteroposterior, lateral, and oblique radiographs to assess fracture pattern, angulation, displacement, and rotation 1. The key decision points are:
- Angulation: Less than 10 degrees is acceptable 1
- Displacement: Any significant displacement requires intervention 2
- Rotation: Any malrotation necessitates reduction 1, 2
- Fracture pattern: Transverse, oblique, or comminuted 2
Treatment Algorithm
For Stable, Minimally Displaced Fractures (<10 degrees angulation)
Buddy splinting is the treatment of choice 1:
- Tape the fifth finger to the fourth finger 1
- Position the metacarpophalangeal joint in 70-90 degrees of flexion (intrinsic plus position) 3
- Allow immediate active range of motion of the interphalangeal joints 4, 3
- Continue for 4-6 weeks until fracture consolidation 1
For Displaced or Angulated Fractures (>10 degrees)
Closed reduction with Kirschner wire fixation is typically required 2:
- Transverse and short oblique fractures respond well to K-wire fixation 2
- Long spiral oblique fractures may require lag screw fixation 2
- Comminuted fractures often need plate fixation 2
Pain Management
- Regular paracetamol (acetaminophen) should be prescribed routinely 5
- Avoid NSAIDs in patients with renal dysfunction 5
- Opioids may be used cautiously if needed, with reduced dosing in renal impairment 6
Dynamic Treatment Protocol
For both operative and non-operative cases, implement protected mobilization 4, 3:
- Immobilize the wrist and metacarpophalangeal joint in intrinsic plus position (wrist dorsiflexed 30 degrees, MCP flexed 70-90 degrees) 3
- Allow immediate active motion of the proximal and distal interphalangeal joints 4, 3
- This achieves bone healing and motion recovery simultaneously rather than sequentially 3
- 86% of patients achieve full range of motion with this approach 3
Follow-Up and Monitoring
- Serial radiographs should be obtained to confirm proper bone healing 5
- Most fractures consolidate by 6 weeks 4
- Monitor for complications including malrotation, malunion, and stiffness 1, 3
Critical Pitfall
Flexor tendon entrapment can occur, particularly in pediatric Salter-Harris type II fractures at the proximal phalanx base 7. If flexion limitation persists despite appropriate treatment, consider this diagnosis and refer for surgical exploration 7.