Treatment of First Metatarsal Fractures
For non-displaced first metatarsal fractures, immobilize with a short leg walking cast or boot for 4-6 weeks with protected weight-bearing, while displaced fractures require rigid internal fixation using AO techniques to prevent malunion and maintain a plantigrade foot. 1, 2
Initial Assessment and Diagnosis
- Obtain proper radiographic evaluation with three standard views (anteroposterior, lateral, and mortise) to accurately diagnose the fracture 3
- Weight-bearing radiographs provide critical information about fracture stability and should be obtained when stability is uncertain 3
- Assess for obvious deformity, displacement, swelling, and ability to bear weight 3
Treatment Algorithm Based on Fracture Pattern
Non-Displaced Fractures
- Use plaster immobilization with a short leg walking cast or boot for 4-6 weeks 1, 2
- Allow protected weight-bearing in a cast shoe during this period 1
- The first metatarsal's thick size and shape make fractures rare, but they require aggressive treatment due to the prolonged disability and altered gait patterns that can result 2
Displaced Fractures
- Perform open reduction with rigid internal fixation using AO techniques 1, 2
- Closed reduction can often be achieved, but maintaining the reduction requires internal fixation 1
- Percutaneous pinning may be suitable for some fractures, though plate fixation is preferred for fractures with joint involvement or multiple fragments 1
Chip Fractures of the First Metatarsal Head
- Consider early fragment excision for distal lateral impaction fractures, which allows faster return to activity (approximately 6 weeks earlier) compared to immobilization alone 4
- Alternative treatment with percutaneous pinning or weight-bearing cast is acceptable but results in longer recovery time 4
Critical Pitfalls to Avoid
The most important complication to prevent is malunion in the sagittal plane, which results in a non-plantigrade foot and long-term disability 2. This is why:
- Any displacement requires aggressive treatment with internal fixation rather than conservative management 2
- The first ray's critical role in normal gait and weight-bearing means even minor malunion can drastically alter function 2
- Prolonged immobilization beyond 6 weeks should be avoided to prevent stiffness and muscle atrophy 3
Special Populations
Patients with Diabetes and Neuropathy
- Pay special attention to proper offloading to prevent ulceration at the fracture site 3, 5
- Ensure proper fitting of any orthotic devices to prevent pressure sores 5
- Monitor closely for wound complications during immobilization 5
Rehabilitation Protocol
- Introduce early physical training and muscle strengthening after the initial immobilization period 3
- Progress to long-term balance training and fall prevention exercises 3
- Avoid prolonged immobilization beyond what is necessary for fracture healing 3