What type of splint is recommended for a mildly comminuted and impacted fracture at the base of the 5th metacarpal with ulnar side angulation?

Splinting for Base of 5th Metacarpal Fracture with Ulnar Angulation

For a mildly comminuted and impacted fracture at the base of the 5th metacarpal with ulnar side angulation, functional metacarpal splinting is recommended as the primary treatment approach, allowing for earlier functional recovery while maintaining adequate fracture stability.

Assessment and Classification

Before splinting, proper assessment is crucial:

• Radiographs should be obtained to evaluate fracture displacement, comminution, and angulation 1
• CT may be considered if radiographs are indeterminate to better visualize fracture morphology 1
• Assess for associated injuries, joint instability, and rotation

Splinting Options and Recommendations

Primary Recommendation: Functional Metacarpal Splint

• Functional metacarpal splinting (FMS) has shown superior early functional outcomes compared to ulnar gutter splinting 2
• Benefits include:
  • Earlier grip strength recovery (normal grip strength by 2 months) 2
  • Faster improvement in functional scores 2
  • Better patient comfort due to less joint restriction 2
  • Adequate prevention of reduction loss for stable fractures 2

Alternative Option: Ulnar Gutter Splint

• Traditional ulnar gutter splinting (UGS) is an acceptable alternative 2
• May be preferred when:
  • Greater immobilization is needed for unstable fractures
  • Patient compliance with functional splinting is questionable
  • Higher degree of angulation (>70°) is present

Duration and Management Protocol

1. Initial Immobilization:

   • Apply functional metacarpal splint after reduction if needed
   • Maintain for 1-3 weeks depending on fracture stability 3, 4

2. Early Mobilization:

   • Begin active finger motion exercises immediately to prevent stiffness 1
   • Progress to controlled mobilization within pain limits after 1 week with functional splinting 3

3. Follow-up Assessment:

   • Evaluate at 1-2 weeks to check for displacement
   • Monitor angulation, as some loss of reduction may occur (noted in studies with both splinting methods) 2

Important Considerations and Pitfalls

• Angulation Threshold: Reduction may not be necessary for angulations less than 70° as studies show good functional outcomes without reduction 3
• Avoid Over-immobilization: Excessive immobilization risks include chronic pain, joint stiffness, muscle atrophy, and complex regional pain syndrome 1
• Surgical Indications: Consider surgical fixation (K-wire or plate) for:
  • Unstable fractures with significant displacement
  • Intra-articular fractures with articular surface disruption
  • Failed conservative management 5, 6
• Rehabilitation: Progressive range of motion exercises should begin after the immobilization period 1
• Ice Application: Recommend ice during the first 3-5 days for symptomatic relief 1

Long-term Outcomes

While functional metacarpal splinting shows better early results, both functional and ulnar gutter splinting yield similar radiological and clinical outcomes by 6 months 2. The key advantage of functional splinting is the quicker return to normal activities and work, typically around 6.5 weeks 4, 6.