What is the treatment for an oblique articular fracture of the proximal fifth phalangeal base?

Treatment for Oblique Articular Fracture of the Proximal Fifth Phalangeal Base

The optimal treatment for an oblique articular fracture of the proximal fifth phalangeal base is closed reduction followed by buddy taping to the fourth digit with immediate mobilization, which provides excellent functional outcomes while minimizing complications. 1

Initial Evaluation and Imaging

• Standard radiographic examination should include 3 views:

  • Posteroanterior (PA) view
  • Lateral view
  • Oblique view 2

• An internally rotated oblique projection, in addition to the standard externally rotated oblique, increases diagnostic yield for phalangeal fractures 2

• If initial radiographs are equivocal, CT without IV contrast may be considered to better visualize the fracture pattern and articular involvement 2

Treatment Algorithm

1. Conservative Management (First-line for most cases)

For base fractures of the fifth proximal phalanx, even with some displacement:

• Perform closed reduction if needed
• Apply buddy taping to the fourth digit
• Begin immediate mobilization 1

This approach has demonstrated:

• High overall patient satisfaction
• Minimal pain at rest or work
• Full flexion recovery in nearly all patients
• Very low rates of malrotation requiring surgery
• No nonunion or delayed union 1

2. Surgical Management (For unstable fractures)

If the fracture is unstable, comminuted, or significantly displaced with articular involvement that cannot be adequately reduced closed:

Option A: Closed Reduction Percutaneous Pinning (CRPP)

• Less invasive
• Similar functional outcomes to open techniques
• Lower rates of extensor lag (41% vs 68% with ORIF) 3

Option B: Open Reduction Internal Fixation (ORIF)

• For comminuted fractures or those with significant articular involvement
• Options include:
  • Lag screws for long oblique fractures 3
  • Plate fixation for comminuted fractures 4
  • Modified bone tie technique for unstable oblique fractures 5

Post-Treatment Protocol

For conservative management:

• Buddy taping to adjacent digit
• Immediate mobilization to prevent stiffness
• Regular follow-up radiographs to ensure proper healing

For surgical management:

• Early protected motion after surgical stabilization
• Pin removal at 3-4 weeks if CRPP was performed
• Hand therapy to optimize range of motion

Common Pitfalls and Considerations

1. Prolonged immobilization risk: Extended static immobilization often leads to stiffness and limitation of interphalangeal joint mobility 6

2. Surgical complications: ORIF with screws may result in higher rates of extensor lag (68%) compared to CRPP (41%) 3

3. Malrotation assessment: Carefully evaluate for rotational alignment during reduction, as malrotation can significantly impact hand function 1

4. Articular step-off: For intra-articular fractures, a step-off of >2mm may lead to long-term complications such as osteoarthritis 2

5. Elderly patients: In patients over 55 years, consider bone quality when selecting treatment method; conservative approaches may be preferred 2

The evidence strongly supports that functional outcomes and patient satisfaction are excellent with conservative management using buddy taping and immediate mobilization for most proximal fifth phalangeal base fractures 1. This approach prioritizes function over perfect anatomical reduction, which aligns with the goal of optimizing quality of life and minimizing morbidity.