Rehabilitation Protocol for Fifth Metacarpal Fracture Fixed with Intramedullary Nail Starting at 2 Weeks Post-Op
At 2 weeks post-operatively for a fifth metacarpal fracture treated with intramedullary nail fixation, begin active range of motion exercises for the metacarpophalangeal (MCP) and interphalangeal (IP) joints while maintaining protective splinting between exercise sessions.
Early Mobilization Phase (Weeks 2-4)
The evidence strongly supports early active mobilization for metacarpal fractures treated with stable internal fixation 1, 2, 3. Begin active finger flexion and extension exercises immediately at the 2-week mark, focusing on:
- Active MCP joint flexion/extension: 10-15 repetitions, 3-4 times daily
- Active IP joint flexion/extension: Full fist-making exercises
- Intrinsic muscle activation: Tabletop position exercises (MCP flexion with IP extension)
Continue protective splinting between exercise sessions during weeks 2-4 to protect the healing fracture 4. Remove the splint only for exercises and hygiene.
Key Principles During This Phase:
- No passive stretching or resistance - only active motion
- Pain should not exceed 3/10 during exercises
- Monitor for swelling, warmth, or increased pain that persists after exercise (signs to slow progression)
Progressive Strengthening Phase (Weeks 4-6)
At 4 weeks post-op, assuming radiographic evidence of healing and no complications 3:
- Discontinue daytime splinting (may continue night splinting if residual stiffness)
- Begin light resistance exercises: Therapeutic putty for grip strengthening
- Progress to functional grasp patterns: Light ADLs including writing, typing, light object manipulation 2
- Grip strengthening: Start with foam ball squeezes, progress resistance gradually
Return to Full Activity (Weeks 6-8)
By 6-8 weeks, most patients achieve union and can progress to unrestricted activities 3, 5:
- Advance to heavy grip strengthening: Hand grippers, weighted exercises
- Sport-specific training: If applicable, begin sport-specific drills with protective taping or buddy taping
- Return to work: Progress from light to medium to heavy work activities based on occupation 2
Objective Criteria for Progression:
- No pain or minimal pain (≤2/10) with activities
- No swelling or warmth at fracture site
- Radiographic union confirmed by surgeon
- MCP flexion ≥70 degrees (expect some deficit compared to contralateral side initially) 4
- Grip strength ≥80% of contralateral side before unrestricted activities 3
Common Pitfalls to Avoid:
Overly aggressive early mobilization can lead to hardware complications - the evidence shows 3.9% complication rate including hardware migration when protocols are followed 3. Stay within pain-free ranges initially.
Prolonged immobilization beyond 2 weeks risks stiffness - the literature consistently shows early mobilization (by 2 weeks) produces superior motion outcomes without increased complications 1, 2, 3.
Ignoring infection signs - cellulitis around hardware occurs in some cases and requires prompt pin removal and antibiotics 4. Monitor for erythema, warmth, and drainage.
Expected Outcomes:
With this protocol, expect:
- Average total active motion of 228 degrees at final follow-up 3
- QuickDASH scores improving by approximately 40 points, with final scores around 17 3
- Return to sport/work typically by 6-8 weeks for most patients 5
The evidence demonstrates that intramedullary nail fixation provides stable enough fixation to allow this early mobilization approach, with union rates approaching 100% and low complication rates when proper rehabilitation protocols are followed 1, 3, 6.