questions
0

Distal Radial Ulnar Joint (DRUJ) Injuries

Author:
Topic updated on 06/16/14 8:51am
Introduction
  • Frequently occur with distal radius fractures but must be considered independently
    • common cause of pain and limited ROM after distal radius fractures
    • often underappreciated and ignored
  • Associated conditions
    • ulnar styloid and distal ulna fractures
    • TFCC tears  
    • ulnar impaction syndrome  
    • Essex-Lopresti injuries
    • Galeazzi fractures  
  • Prognosis
    • primary method to prevent disability related to DRUJ injuries is anatomic reduction of the distal radius which often results in an anatomically-reduced DRUJ
Anatomy
  • DRUJ
    • arthrology 
      • articulation occurs between the ulnar head and sigmoid notch (a shallow concavity found along ulnar border of distal radius)
      • most stable in supination
    • primary stabilizers
      • volar and dorsal radioulnar ligaments 
      • TFCC 
        • TFCC attaches to the fovea at the base of the ulnar styloid
        • components include
          • central articular disc
          • meniscal homologue
          • volar and dorsal radioulnar ligaments
          • ulnolunate and ulnotriquetral ligament origins
          • floor of the ECU tendon sheath
    • biomechanics
      • joint motion includes both rotation and translation
Presentation
  • Symptoms
    • pain and instability with acute DRUJ dislocation
    • dorsal wrist pain and limited pronosupination with post-traumatic arthritis
  • Physical exam
    • post-traumatic arthritis
      • snapping and crepitus
      • proximal rotation of the forearm with compression of the ulna against the radius elicits pain
      • decreased grip strength
Imaging
  • Radiographs 
    • AP shows widening of the DRUJ
    • lateral shows dorsal displacement
      • instability of the DRUJ is present when the ulnar head is subluxed from the sigmoid notch by its full width with the arm in neutral rotation
  • Dynamic CT
    • useful in the diagnosis of subtle chronic DRUJ instability
    • sequential CT scans are performed with the forearm in neutral and full supination and pronation
    • >50% translation compared to the contralateral side is abnormal
  • MRI
    • useful in the identification of TFCC injuries 
Treatment
  • Nonoperative
    • closed reduction, immobilization
      • indications
        • DRUJ instability resulting from purely ligamentous injury
      • techniques
        • closed reduction and immobilization in a position of stability for 4 weeks
          • dorsal instability is stable with the forearm in supination
          • volar instability is stable in pronation
      • outcomes
        • interposition of ECU may impede closed reduction
  • Operative
    • DRUJ pinning, radioulnar ligament repair
      • indications
        • highly unstable DRUJ
      • techniques
        • pinning across joint with 0.062-inch K-wires
Ulnar Styloid Fractures
  • Reflects high degree of initial fracture displacement
  • Fractures through base often associated with TFCC rupture and instability
  • Painful hypertrophic nonunions can occur in the absence of instability
  • Treatment
    • nonoperative
      • cast immobilization
        • indications
          • nondisplaced fractures proximal to the ulnar styloid
    • operative 
      • ORIF, symptomatic fragment excision
        • indications
          • displaced fractures through the base with associated instability
          • sigmoid notch fractures
          • Galeazzi fracture patterns
          • TFCC avulsions in the face of an unstable DRUJ
        • techniques
          • preserve ulnar attachments of TFCC with fragment excision
TFCC Tears
  • Mechanism of injury
    • wrist extension, forearm pronation
      • in pronation, volar ligaments prevent dorsal subluxation
      • in supination, dorsal ligaments prevent volar subluxation
  • Classification
    • type I - traumatic
    • type II - degenerative (ulnocarpal impaction)
      • IIA - TFCC thinning
      • IIB - IIA + lunate and/or ulnar chondromalacia
      • IIC - IIB + TFCC perforation
      • IID - IIC + LT ligament disruption
      • IIE - IID + ulnocarpal and DRUJ arthritis
  • Treatment
    • nonoperative
      • immobilization, NSAIDS
        • indications
          • all acute traumatic TFCC tears
    • operative
      • arthroscopic vs. open debridement and/or repair post
        • indications
          • failure of nonoperative management
          • persistent symptoms
        • techniques
          • type I injuries
            • arthroscopic vs. open debridement and/or repair
          • type II injuries
            • TFCC pathology treated with arthroscopic or open debridement
            • ulnocarpal impaction treated with ulnar shortening osteotomy (in the absence of DRUJ arthrosis) or wafer resection of the ulnar head
Ulnar Impaction Syndrome
  • Radial shortening leads to positive ulnar variance and altered mechanics
  • Sequelae includes
    • lunate chondromalacia
    • degenerative TFCC tears
  • Operative treatment
    • TFCC debridement
    • radial osteotomy
    • ulnar shortening post
    • distal ulnar resection (Wafer procedure)
      • preserve ulnar attachment of TFCC
Essex-Lopresti Injuries
  • Radial head fracture with an interosseous membrane injury extending to DRUJ 
    • unstable relationship between ulna and radius
    • leads to proximal migration of the radius
    • results in secondary DRUJ pathology and ulnocarpal abutment
  • Treatment
    • treat bony pathology (radial head or shaft)
    • pin DRUJ for 6 weeks in neutral to facilitate ligamentous healing
    • if pinning fails (or the initial injury is missed) radial head replacement may be required
Galeazzi Fractures
  • Distal one-third fracture of the radius and a DRUJ injury
  • ECU entrapment may cause DRUJ to be irreducible
  • Treatment
    • nonoperative
      • splint in supination
        • indications
          • rarely indicated for stable injuries
    • operative
      • radial ORIF and DRUJ pinning
        • indications
          • often required to achieve a stable reduction
Complications
  • DRUJ arthrosis
    • treatment
      • resection arthroplasty (resect distal ulna)
        • matched resection vs. Darrach post
          •  Darrach procedure 
            • reserved for low-demand, elderly patients
            • an unstable, painful proximal ulna stump may result
      • hemiresection or interposition arthroplasty
        • ulnar insertion of TFCC is preserved
        • radioulnar impingement is prevented by soft tissue interposition
      • Sauve-Kapandji procedure 
        • DRUJ fusion with creation of a proximal ulnar neck pseudoarthrosis
      • ulnar head prosthetic replacement
      • creation of a one-bone forearm
        • ultimate salvage procedure that eliminates forearm rotation

 

Please Rate Educational Value!
2.0
Average 2.0 of 18 Ratings

Qbank (0 Questions)





Evidence & References Show References




Topic Comments