Die-punch fracture
Background
- Die-punch fracture is a depressed fracture of the lunate fossa of the distal radius
- Caused by axial load transmitted through the lunate onto the lunate facet
- Often occurs with fall on outstretched hand (FOOSH)
- May be associated with other distal radius fractures patterns
- Can be easily missed on plain radiography
Clinical Features
- Wrist pain and swelling after axial loading injury
- Tenderness over the distal radius, particularly the ulnar aspect
- Decreased grip strength
- Limited wrist range of motion (especially extension)
Differential Diagnosis
Forearm Fracture Types
- Distal radius fractures
- Radius and ulna fracture (both-bone forearm fracture)
- Radial head fracture
- Isolated ulna fracture (i.e. nightstick)
- Monteggia fracture-dislocation
- Galeazzi fracture-dislocation
- Essex-Lopresti fracture
- Forearm fracture (peds)
Evaluation
Workup
- Wrist X-ray: PA, lateral, and oblique views
- Look for a depressed articular fragment on the lateral view
- Subtle step-off on PA view
- CT scan recommended to fully characterize fracture pattern and articular depression
Diagnosis
- CT scan is the gold standard for identifying and classifying the fracture
- Fracture involves depression of the lunate facet of the distal radius articular surface
Management
- Non-displaced (<2mm step-off): Sugar tong splint with orthopedic follow-up
- Displaced (≥2mm articular step-off): operative fixation (ORIF) to restore articular congruity
- Early orthopedic consultation for most cases given intra-articular involvement
Disposition
- Discharge with orthopedic follow-up if non-displaced and splinted
- Orthopedic consultation in ED if displaced or significant comminution