Treatment of Metacarpal (Boxer) Fracture
For most fifth metacarpal neck fractures (boxer fractures), conservative management with immobilization followed by early mobilization provides equivalent functional outcomes to surgery, even with angulation up to 70 degrees, and should be the preferred initial treatment. 1, 2
Initial Assessment and Imaging
- Obtain standard three-view radiographs (posteroanterior, lateral, and 45° semipronated oblique) to properly visualize the fracture 3, 4
- An internally rotated oblique projection increases diagnostic yield for metacarpal fractures 3
- CT imaging is typically not indicated for acute metacarpal fractures unless there is concern for complex articular involvement 3, 4
- Assess specifically for: rotational deformity, degree of volar angulation, open fracture, and intra-articular extension 1, 5, 6
Treatment Algorithm
Conservative Management (Preferred for Most Cases)
Indications:
- Closed fractures without rotational deformity 1, 2, 6
- Volar angulation up to 70 degrees 2
- No intra-articular extension 4, 6
Treatment approach:
- Apply rigid immobilization with ulnar gutter splint or cast (preferred over removable splints for displaced fractures) 4
- Alternative: Pressure bandage for 1 week followed by immediate mobilization provides equivalent outcomes 2
- Duration: 3 weeks of immobilization 2
- Initiate active finger motion exercises immediately to prevent stiffness 3, 4
Evidence supporting conservative management: A 2020 meta-analysis demonstrated that conservative treatment provides equivalent functional outcomes (Quick-DASH scores, grip strength, Total Active Motion, pain scores) compared to operative management, despite worse radiological angulation at follow-up 1. Critically, conservative management resulted in fewer mean days off work and avoided surgical complications 1. A prospective randomized trial showed that immediate mobilization after 1 week of pressure bandaging for fractures with up to 70 degrees angulation resulted in satisfied patients with good range of motion and no significant pain 2.
Surgical Management
Indications:
- Open fractures 4, 6
- Rotational deformity (malrotation of the fifth finger) 5, 6
- Severe soft-tissue swelling combined with volar angulation >30 degrees and malrotation 5
- Intra-articular extension requiring fixation 6
Surgical technique:
- Percutaneous transverse K-wire pinning is effective for displaced fractures with severe swelling 5
- This technique is easy to perform and provides good results with mean DASH scores of 5 at 25-month follow-up 5
Rehabilitation Protocol
- Begin active finger motion exercises immediately following diagnosis and treatment—this is critical to prevent stiffness, the most common functionally disabling complication 3, 4
- Wrist motion does not need early initiation following stable fracture fixation 3
- Include muscle strengthening exercises as part of rehabilitation 4
- Continue long-term hand exercises 4
- Consider vitamin C supplementation for prevention of disproportionate pain 3
Follow-Up and Monitoring
- Radiographic follow-up at approximately 3 weeks and at cessation of immobilization 4
- Monitor for finger stiffness (most common complication) 3
- Assess for rotational deformity and grip strength deficits 5
- Immediate emergency care if the fractured extremity appears blue, purple, or pale 4
Key Clinical Pitfalls
Common mistake: Over-treating with surgery based solely on radiographic angulation. The evidence clearly shows that angulation up to 70 degrees does not compromise functional outcome 1, 2. Surgical intervention exposes patients to operative risks without functional benefit in most cases.
Critical point: Rotational deformity is not acceptable and requires surgical correction, unlike angulation which is well-tolerated 5, 6. Always assess for malrotation by examining the cascade of fingers during flexion.
Stiffness prevention: The single most important factor for good outcomes is early finger motion 3. Prolonged immobilization or delayed mobilization leads to the most common functionally disabling complication.