Treatment of Dorsal Talonavicular Avulsion Fracture on the Talus
For dorsal talonavicular avulsion fractures on the talus, obtain CT imaging immediately to determine fragment size and displacement, then proceed with surgical fixation if the fragment is ≥15mm or displaced >2mm, otherwise treat conservatively with immobilization and protected weight-bearing for 6 weeks. 1, 2
Diagnostic Workup
Initial Imaging
- Standard three-view ankle radiographs are the starting point, but these frequently miss or underestimate the extent of talar avulsion fractures 2, 3
- CT scan is mandatory after radiographs to determine fragment size, displacement, comminution, and intra-articular extension 1, 2
- MRI without IV contrast should be obtained to assess for associated cartilage abnormalities, bone contusions, and ligamentous injuries—this is particularly important since 70% of ankle fractures result in cartilage injury 1
Clinical Examination Pitfall
- The Ottawa Ankle Rules do not include routine palpation of the talus, leading to missed diagnoses in approximately 37% of cases 3
- Directly palpate the dorsal talus during examination to avoid missing these injuries, as patients given incorrect initial diagnoses experience significant anxiety and concern 3
Treatment Algorithm
Surgical Indications (Operative Management)
Proceed with open reduction and internal fixation if ANY of the following criteria are met:
- Fragment size ≥15mm 1
- Any displacement >2mm 1
- Intra-articular extension with displacement 1
- Larger fragments with joint instability 4
Surgical technique:
- Open reduction with screw fixation or K-wires for larger fragments 4
- Arthroscopic removal is acceptable only for small flake fractures with confirmed joint stability 4
Post-operative protocol:
- Non-weight bearing for 6-8 weeks 1
- Progressive weight-bearing only after radiographic confirmation of adequate healing 1
Conservative Management (Non-operative)
Treat conservatively when:
- Fragments are small, non-articular, or minimally displaced 2
- No displacement >2mm and fragment <15mm 1
Conservative protocol:
- Immobilization in a cast or fixed-ankle walker-type device 2
- Protected weight-bearing for 6 weeks 2
- Radiographic follow-up at approximately 3 weeks to confirm adequate healing 2
Critical Timing Considerations
Early diagnosis and treatment are essential for optimal outcomes. Patients diagnosed and treated acutely with appropriate immobilization achieve excellent results, while missed fractures predictably do poorly with persistent posteromedial ankle pain 5. For patients with delayed diagnosis, late surgical excision can provide significant functional improvement, though outcomes remain inferior to acute treatment 5.