Treatment of Lateral Chip Fracture at the Base of the 1st Metatarsal
For a lateral chip fracture at the base of the 1st metatarsal, early fragment excision is the preferred treatment approach, allowing return to full activity approximately 6 weeks faster than immobilization alone. 1
Initial Diagnostic Evaluation
- Obtain standard three-view radiographs (anteroposterior, lateral, and mortise views) to confirm the diagnosis and assess fracture characteristics 2
- Weight-bearing radiographs should be obtained if possible to assess stability, particularly looking for displacement or joint involvement 2
- The lateral chip fracture represents a distal lateral impaction fracture pattern that can be missed on routine views 1
Treatment Algorithm
For Displaced or Symptomatic Fragments:
Primary fragment excision is recommended as it provides:
- Faster return to full activity (6-week advantage over conservative treatment) 1
- Immediate removal of mechanical irritation 1
- Avoidance of prolonged immobilization complications 1
The surgical approach involves early removal of the fracture fragment through a minimally invasive technique, which has demonstrated successful outcomes in all reported cases 1, 3
For Minimally Displaced Fragments:
Conservative management options include:
- Short-term immobilization with either a hard-soled shoe or CAM-walker boot 4
- Weight-bearing as tolerated with appropriate footwear 4
- Expected healing time of 7-9 weeks with immobilization 4
Post-Treatment Management
- Early mobilization and rehabilitation should begin once initial treatment is completed 2
- Functional support (brace or appropriate footwear) facilitates return to activities 2
- Follow-up radiographs at 4,8, and 12 weeks to confirm healing if treated conservatively 4
Critical Considerations
- Avoid prolonged immobilization beyond what is necessary, as this leads to stiffness and muscle atrophy requiring extended rehabilitation 5
- The lateral base of the 1st metatarsal is the insertion site for peroneus longus, making these fractures potentially unstable if significantly displaced 3
- If the fragment cannot be adequately reduced or causes persistent symptoms, surgical excision should not be delayed 1
Key Pitfall to Avoid
Do not mistake this injury for a simple ankle sprain or overlook it on initial radiographs—the lateral chip fracture requires specific attention to the base of the 1st metatarsal on all three standard views 2, 1