29 y/o female presents to the ED w/ L wrist pain. She is s/p MVC where she was the restrained driver in a head-on collision. On examination, a deformity is noted in her distal left forearm, but she is able to move her fingers, has intact sensation throughout hand, and normal capillary refill. What is the diagnosis? (Scroll down for answer) 

Answer: Radiocarpal Dislocation (with radial and ulnar styloid fractures)

• Background
• Defined as loss of contact between radius and carpus 
• dislocation may occur dorsal (more common) or volar
• Mechanism of injury: high energy shear or rotational force to hyperextended/pronated wrist (MVC, fall, industrial accidents)
• Commonly associated with fracture, but may be associated with ligamentous injury
• common fractures include:  cortical rim of distal radius, radial styloid, ulnar styloid
• Presentation
• usually presents with swollen, painful wrist with deformity (+/`- numbness/paresthesias)
• Diagnosis
• Obtain plain films of wrist in PA/lateral view
• PA view: assess radiolunate alignment
• Lateral view: will see dorsal or volar radiocarpal dislocation
• Treatment
• Closed reduction, but ORIF often required 
• Indications for ORIF:  open injuries, inability to reduce, neurovascular injury, unstable radiocarpal joint after reduction
• ED Management
• assess NV status
• plain films
• pain control 
• closed reduction w/ longitudinal traction
• immobilization
• ortho/hand consult 

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