Proximal Metacarpal Fracture Splinting
For proximal metacarpal fractures, use a hand-based functional splint that immobilizes the affected metacarpal while allowing motion at the metacarpophalangeal (MCP), interphalangeal (IP), and radiocarpal joints.
Splint Selection Algorithm
Hand-Based Functional Splint (Preferred)
- Immobilizes only the fractured metacarpal while permitting full motion of MCP, IP, and wrist joints 1
- Allows immediate return to work and activities in most patients 1
- Maintains fracture reduction as effectively as traditional splints 1
- Average splinting duration is approximately 24 days 1
Specific Considerations by Location
For 5th metacarpal fractures:
- Functional metacarpal splint (FMS) provides faster functional recovery compared to ulnar gutter splint 2
- FMS allows patients to reach expected grip strength by 2 months, whereas ulnar gutter splint patients show significantly lower grip strength at 2 months (p=0.008) 2
- QuickDASH scores improve significantly faster with FMS between 2nd and 6th month follow-up (p=0.003) 2
For 4th (ring finger) metacarpal fractures:
- If using an ulnar gutter splint, include the middle finger to prevent iatrogenic rotational deformity 3
- Including only ring and small fingers can cause distal fragment pronation, leading to crossover deformity 3
- At 10 lbs of force, 2-finger positioning causes significantly more rotation (2.8mm) versus 3-finger positioning (1.8mm) (p<0.05) 3
Key Clinical Advantages
Functional outcomes with hand-based splints:
- 20 out of 24 employed patients continued working without missing any days 1
- Maintains functional motion throughout treatment period 1
- Low patient morbidity compared to traditional immobilization 1
- Excellent maintenance of fracture reduction: 27 of 30 patients showed no change in alignment from start to end of splinting 1
Critical Pitfalls to Avoid
- Avoid overzealous molding of ulnar gutter splints, which can cause iatrogenic pronation of the distal metacarpal fragment 3
- Do not restrict unnecessary joints - immobilizing adjacent uninjured joints delays functional recovery and return to work 1, 2
- Ensure early mobilization is incorporated into treatment plan to prevent stiffness, which is a major complication following metacarpal fractures 4, 5
Duration and Follow-up
- Initial radiographic follow-up should confirm maintained reduction 1
- Average splinting duration is 3-4 weeks for stable fractures 1, 6
- Both functional and traditional splints achieve similar long-term radiological outcomes by 6 months, but functional splints provide superior early functional recovery 2