| Introduction |
 A fracture of the distal radial shaft with disruption of the distal radioulnar joint (DRUJ)
- disruption of the DRUJ in a pediatric patient can consist of a dislocation or, more commonly, a displaced ulnar physeal injury
- Epidemiology
- relatively rare injury, less frequent than in adults
- more common in older children and adolescents
- Mechanism
- axial loading in combination with extremes of forearm rotation (pronation or supination)
- pronation produces an apex dorsal radial fracture with the distal ulna displaced dorsally
- supination produces an apex volar radial fracture with the distal ulna displaced volarly
- Associated injuries
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| Relevant Anatomy |
- DRUJ possesses poor bony conformity in order to allow some translation with rotatory movements
- Ligamentous structures are critical in stabilizing the radius as it rotates about the ulna during pronation and supination
- triangular fibrocartilage complex (TFCC) is a critical component to DRUJ stability
- the joint is most stable at the extremes of rotation
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| Presentation |
- Symptoms
- wrist and forearm pain and radial deformity are typically present with limitation of wrist motion
- ulnar head prominence or deformity can be sometimes be seen
- Physical exam
- pain with movement of palpation of the wrist
- DRUJ instability may be appreciated by local tenderness and instability to testing of the DRUJ
- careful exam for nerve injury
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| Imaging |
- Radiograhs
- APradiographs reveal displaced distal radial shaft fracture
- DRUJ disruption or distal ulnar injury may be subtle and radiographs must be scrutinized
- true lateral radiograph is essential in determining the direction of displacement
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| Treatment |
- Treatment goals
- requires anatomic reduction of both the radius fracture and the DRUJ
- Nonoperative
- closed reduction with long arm casting
- indications
- indicated in younger patients (higher likelihood of successful nonoperative treatment than in adults)
- technique
- immobilize in the rotatory stable position (most commonly stable in supination)
- Operative
- open reduction internal fixation +/- DRUJ pinning
- indications
- recommended in adolescents
- irreducible DRUJ due to interposed tendon or periosteum
- technique
- pin DRUJ if unstable in all planes
- irreducible DRUJ can be seen with interposed tendon or periosteum and requires an open reduction to remove interposed material
- ECU most common interposed tendon
- ORIF, soft tissue reconstruction of DRUJ and TFCC, +/- corrective osteotomy
- indications
- chronic DRUJ instability (a rare consequence of a missed injury)
- technique
- if the DRUJ subluxation is caused by a radial malunion, a corrective osteotomy is also required in addition to reconstruction, otherwise a soft tissue reconstruction of the DRUJ alone will fail
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