Treatment of Displaced and Angulated Fracture of the 5th Metacarpal Head
For a displaced and angulated fracture of the 5th metacarpal head in a young to middle-aged adult, surgical fixation with percutaneous Kirschner wire (K-wire) pinning is recommended, particularly when volar angulation exceeds 30° or when malrotation is present. 1
Indications for Surgical Intervention
Surgical treatment is indicated when:
- Volar angulation of the metacarpal head is greater than 30° 1
- Malrotation of the fifth finger is present 1
- Significant displacement compromises hand function 2
- Severe soft-tissue swelling accompanies the fracture 1
The head of the 5th metacarpal is distinct from the more common neck fractures (boxer's fractures), and displaced head fractures typically require operative management due to their intra-articular or juxta-articular nature and inherent instability. 3
Surgical Technique Selection
Percutaneous transverse K-wire pinning is the preferred surgical method for displaced 5th metacarpal head fractures, offering excellent functional outcomes with minimal complications. 1 This technique is particularly advantageous when severe soft-tissue swelling is present, as it avoids extensive soft tissue dissection. 1
Alternative fixation methods include:
- Intramedullary compression screws for spiral or shaft extension fractures 4
- Open reduction with multiple K-wire pinning for comminuted fractures or when closed restoration of the articular surface is not feasible 3
- Plate and screw fixation for complex fracture patterns 2, 5
The choice between K-wire and intramedullary screw fixation shows no significant difference in total active range of motion, rotation, bone healing, or complication rates, though intramedullary screws may trend toward earlier return to work. 4
Expected Outcomes and Follow-up
Patients treated with percutaneous K-wire pinning typically achieve:
- Full extension of the fifth finger (with rare exceptions of 10° limitation without functional impairment) 1
- At least 90° flexion of the fifth metacarpophalangeal joint 1
- Full range of motion of interphalangeal joints 1
- No rotational deformity or grip strength deficit 1
- Mean DASH score of 5 at medium-term follow-up (average 25 months) 1
Critical Management Considerations
Avoid conservative management pitfalls: While some metacarpal fractures can be treated non-operatively, displaced head fractures are inherently unstable. 3 Inadequate reduction may result in chronic pain, functional disability, and post-traumatic osteoarthritis. 3
Timing of surgery: Perform reduction and pinning promptly, as severe soft-tissue swelling can complicate delayed surgical intervention. 1 The procedure should be performed using image intensification to ensure adequate reduction and pin placement. 3
Postoperative care: Tailor immobilization and rehabilitation to the fracture pattern and fixation method used. 2 Early controlled motion protocols may be initiated once stability is confirmed, though specific splint duration varies by surgeon preference and fracture stability. 4
Restoration of articular surface: For intra-articular fractures, meticulous restoration of the joint surface is essential to prevent long-term arthritic changes. 3 Open reduction should be performed when closed techniques cannot achieve adequate articular congruity. 3