What is the most reliable splint for a closed, nondisplaced boxer fracture of the distal fourth or fifth metacarpal?

Best Splint for Boxer Fracture

For a closed, nondisplaced boxer fracture (fifth metacarpal neck), use either a functional hand-based splint or an ulnar gutter splint—both maintain reduction equally well, but the functional hand-based splint allows faster return to work and better early grip strength.

Primary Splint Options

Functional Hand-Based Splint (Preferred for Most Patients)

• A hand-based functional splint allows metacarpophalangeal (MCP), interphalangeal (IP), and radiocarpal joint motion throughout treatment 1
• This approach maintains fracture reduction in 90% of cases (27 of 30 patients showed no alignment change from start to finish) 1
• Patients return to work immediately—20 of 24 employed patients missed zero work days 1
• Average splint duration is 24 days 1
• Grip strength recovers faster: patients reach expected strength values by 2 months, significantly earlier than with ulnar gutter splinting 2
• QuickDASH scores improve significantly between 2 and 6 months (p = 0.003) 2

Ulnar Gutter Splint (Traditional Alternative)

• The ulnar gutter splint is a proven, simple method for immobilizing boxer's fractures 3
• Maintains reduction adequately but restricts more joint motion 2
• At 2-month follow-up, grip strength remains significantly lower compared to functional splints (p = 0.008) 2
• By 6 months, radiological and clinical outcomes are equivalent to functional splints 2

Key Technical Points

Initial Reduction

• Both splint types achieve significant correction after reduction 2
• Functional splints show better initial angulation (16° ± 7°) compared to ulnar gutter splints (21° ± 8°, p = 0.043) 2
• However, functional splints lose some reduction by 1-month follow-up (from 16° to 21°, p = 0.009), though this remains clinically acceptable 2

Dynamic Stabilization Option

• Dynamic metacarpal stabilization splints (DMSS) provide superior early outcomes compared to static plaster splints 4
• ROM of IP and MCP joints is statistically better at 1 month (p < 0.001), though equivalent by 3 months 4
• Wrist ROM remains better at 3 months with DMSS (p < 0.05) 4
• Self-care, daily activities, pain, and anxiety scores are better at all follow-up visits (p < 0.05) 4
• Caution: Skin lesions occur in approximately 10% of DMSS patients (5 of 52) versus 0% with plaster (p = 0.008) 4

Immediate Management Protocol

Early Mobilization

• Initiate active finger-motion exercises immediately after splint application to prevent stiffness, the most functionally disabling complication 5
• The splint must be easily removable to allow active ROM exercises several times daily 5
• This early mobilization approach applies to all minimally displaced metacarpal fractures 1

Radiographic Follow-Up

• Obtain radiographs at 3 weeks to verify maintained alignment 5
• Continue monitoring until immobilization ends 5
• Average treatment duration is 24 days for functional splints 1

Clinical Decision Algorithm

Choose functional hand-based splint when:

• Patient needs immediate return to work 1
• Occupation requires early grip strength 1
• Patient compliance with ROM exercises is expected 1

Choose ulnar gutter splint when:

• Traditional immobilization is preferred 3
• Patient compliance with ROM exercises is uncertain 2
• Simpler application is needed 3

Consider dynamic stabilization splint when:

• Fastest functional recovery is priority 4
• Patient can tolerate potential skin irritation 4
• Early wrist ROM is critical for occupation 4

Common Pitfalls

• Avoid rigid immobilization that prevents finger motion—this causes preventable stiffness 5, 1
• Do not assume functional splints will lose reduction—they maintain alignment in 90% of cases 1
• Immobilization-related complications (skin irritation, muscle atrophy) occur in approximately 15% of cases regardless of splint type 5
• While dynamic splints offer faster recovery, monitor for skin lesions which occur in 10% of patients 4