Volar Marginal Rim Fracture Management
Volar marginal rim fractures of the distal radius require fragment-specific volar hook plate fixation combined with aggressive assessment and treatment of associated carpal injuries, as these fractures have significantly higher rates of scapholunate instability, carpal dislocation, and fixation failure compared to other distal radius fractures. 1
Initial Assessment and Diagnosis
Critical Radiographic Evaluation
- Obtain standard wrist radiographs (PA, lateral, and oblique views) to identify the volar marginal rim fragment involving the volar ulnar corner of the distal radius 2
- Assess for associated carpal injuries systematically, as volar marginal rim fractures have 2.52 associated carpal injuries per patient versus 1.64 for other distal radius fractures 1
- Specifically evaluate for:
Advanced Imaging When Indicated
- CT arthrography has nearly 100% sensitivity for detecting scapholunate ligament tears and 80-100% sensitivity for lunotriquetral ligament tears, with superior accuracy compared to MRI for partial ligament tears 2
- MRI at 3T with dedicated wrist coils should be considered when ligamentous injury is suspected but not clearly demonstrated on plain films 2
Surgical Management Algorithm
Fragment-Specific Fixation Approach
- Use volar hook plate specifically designed for volar marginal rim fragments as the primary fixation method for the critical volar ulnar corner 3
- Ensure the hook plate is fully seated to minimize hardware irritation; newer third-generation designs have modified the prominent bend that caused complications in earlier versions 3
- Combine with additional fragment-specific fixation techniques as needed for other fracture components in AO type B3 or C fractures 3
Addressing Associated Carpal Instability
- Directly address scapholunate instability intraoperatively when identified, as 56% of volar marginal rim fractures demonstrate persistent carpal instability postoperatively despite adequate fracture fixation 1
- Assess for carpal subluxation under fluoroscopy after provisional fixation and before final construct completion 1
- Consider supplemental carpal ligament repair or reconstruction when significant instability persists after fracture reduction 1
Common Pitfalls and Complications
Hardware-Related Issues
- Hardware irritation requiring removal occurs in approximately 19% of cases (5 of 26 wrists), with 4 requiring complete hardware removal including the volar hook plate 3
- Second-generation hook plates with prominent bends had higher irritation rates; ensure use of current-generation designs 3
- No tendon ruptures occurred in the reported series when proper technique and modern implants were used 3
Fixation Failure Risk
- Volar marginal rim fractures have 24% fixation failure rate compared to 0% in other distal radius fractures, necessitating closer postoperative monitoring 1
- Revision surgery is required in 12% of cases versus 0% for other distal radius fractures 1
- Loss of fixation of the critical volar ulnar corner did not occur when fragment-specific volar hook plates were properly applied 3
Postoperative Monitoring
Radiographic Surveillance
- Obtain immediate postoperative radiographs to document reduction and hardware position 3
- Serial radiographs at 2,6, and 12 weeks to monitor for loss of reduction, carpal subluxation, or hardware complications 1, 3
- Specifically assess for:
Clinical Follow-up
- Average follow-up of 9 months minimum is recommended given the high complication rate 3
- Assess for flexor tendon irritation symptoms at each visit, as hardware prominence can cause delayed symptoms 3
- Monitor for signs of persistent carpal instability including pain with loading, clicking, or weakness 1