What is the treatment for a 5th metacarpal fracture?

Treatment of 5th Metacarpal Fractures

The treatment of 5th metacarpal fractures should focus on functional taping or splinting rather than rigid cast immobilization, as this leads to faster functional recovery while maintaining adequate fracture healing.

Initial Assessment and Classification

• Obtain standard radiographs (PA, lateral, and oblique views) to assess:

  • Fracture location (base, shaft, neck, or head)
  • Displacement and angulation
  • Intra-articular involvement
  • Comminution
  • Rotational deformity (best assessed clinically)

• Additional imaging:

  • CT may be considered for complex intra-articular fractures at the base 1
  • MRI is not routinely indicated for acute metacarpal fractures 1

Non-Operative Management

Indications for Non-Operative Treatment:

• Non-displaced or minimally displaced fractures
• Angulation <30 degrees for shaft fractures
• Shortening <5mm
• No rotational deformity or <10 degrees
• No significant intra-articular involvement

Non-Operative Treatment Options:

1. Functional Taping (Preferred Method)

   • Buddy taping to adjacent finger with early active motion
   • Provides better functional outcomes than cast immobilization 2
   • Results in quicker recovery with comparable anatomical results at 6 months 2
   • Allows for immediate active protected mobilization 3

2. Hand-Based Splinting

   • Alternative to buddy taping
   • Allows metacarpophalangeal, interphalangeal, and radiocarpal joint motion
   • Maintains fracture reduction while preserving function 4
   • Enables early return to pre-injury activities with low morbidity 4

3. Duration of Immobilization

   • 3-4 weeks is typically sufficient 5
   • Immobilization beyond this period is unnecessary and may lead to stiffness 5
   • Fracture healing is typically complete by 6-8 weeks

Rehabilitation Protocol:

• Active finger motion exercises should begin immediately to prevent stiffness 6
• Progressive range of motion exercises after the immobilization period 6
• Gradual return to activities as tolerated 6
• Ice application during first 3-5 days for symptomatic relief 6

Surgical Management

Indications for Surgical Treatment:

• Intra-articular fractures with displacement or articular incongruity
• Unstable fractures with significant displacement
• Open fractures
• Multiple fractures
• Fractures with rotational deformity >10 degrees
• Failed conservative management

Surgical Options:

1. Closed Reduction and Percutaneous Pinning

   • Preferred for most displaced fractures requiring surgery 7
   • Uses Kirschner wires under image intensifier guidance
   • Less invasive than open reduction

2. Open Reduction and Internal Fixation

   • Reserved for comminuted fractures or when closed reduction is not feasible 7
   • May use K-wires, mini plates, or screws depending on fracture pattern

Special Considerations

Base of 5th Metacarpal Fractures

• These fractures are inherently unstable and may require more aggressive treatment 7
• Intra-articular fractures at the base often benefit from surgical intervention to restore articular congruity 7
• Restoration of the articular surface is important to prevent osteoarthritic changes 7

Boxer's Fracture (5th Metacarpal Neck Fracture)

• Common subtype of 5th metacarpal fracture
• Can tolerate greater angulation (up to 40-45 degrees) than other metacarpal fractures
• Functional taping is particularly effective for these fractures

Follow-up and Monitoring

• Clinical and radiographic assessment at:

  • 1-2 weeks (to check for secondary displacement)
  • 4 weeks (to assess healing and consider discontinuation of immobilization)
  • 8 weeks (to confirm healing and functional recovery)

• Monitor for complications:

  • Malunion (common but often well-tolerated functionally)
  • Stiffness (more common with prolonged immobilization)
  • Pain with gripping
  • Rotational deformity (causing finger overlap)

Prognosis

• Most 5th metacarpal fractures heal well with appropriate treatment
• Functional outcomes are generally good regardless of treatment method by 6 months 2
• Secondary displacement occurs in approximately 11% of cases treated with functional taping, but rarely affects final outcomes 3
• Complete fracture healing typically occurs by 8 weeks, with 37% healed by 1 month and 100% by 2 months 3