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Duke Orthopaedics
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Wheeless' Textbook of Orthopaedics

Monteggia's Fracture             


- See:
      - Plating Techniques
      - Monteggia Fractures in Children

- Discussion:
    - Giovanni Monteggia (1814) first described frx of proximal 1/3 of ulna in association w/ anterior dislocation of radial head;
          - hence dislocation of radial head w/ frx of proximal 1/3 of ulna is known as Monteggia's deformity.
    - Mechanism:
           - proposed mechanisms include direct blow & hyperpronation injuries as well- as the hyperextension theory;



- Type I (or extension type) - 60% of cases:
    - anterior dislocation of radial head (or frx) and fracture of ulnar diaphysis at any level w/ anterior angulation (usually proximal third);
    - exam:
           - attempt to palpate radial head (ant, post, or lateral);
           - PIN palsy is most common in type I frx and may occur in a delayed fashion if the radial head is not promptly reduced;
    - reduction:
           - achieved w/ forarm in full supination, & longitudinal traction;
           - then elbow is gently flexed to > 90 deg to relax biceps;
           - radial head is gently repositioned by direct manual pressure anteriorly on the bone;
           - following reduction, radial head will be stable if left in flexion;
           - angulated ulnar shaft is reduced by firm manual pressure;

             



- Type II (flexion type) - 15%
     - posterior or posterolateral dislocation of radial head (or frx);
     - frx of proximal ulnar diaphysis with posterior angulation;
     - posterior Monteggia frx is reduced by applying traction to forearm w/ the forearm in full extension;
           - immobilization is continued until there is union of the ulna;
           - this ordinarily requires 6-10 wks depending on the age of pt;



- Type III - 20%
     - lateral or anterolateral dislocation of the radial head;
     - fracture of ulnar metaphysis;
     - frx of ulna just distal to coronoid process w/ lateral dislocation of radial head;

       



- Type IV (5%)
     - anterior dislocation of the radial head;
     - frx of proximal 1/3 of radius & frx of ulna at the same level;


- Exam:
     - r/o tear of the annular ligament
     - associated nerve injury:
           - paralysis of deep branch of radial nerve is most common;
                 - posterior interosseous nerve may be wrapped around neck of radius, preventing reduction;
                 - note: that patients whose operative treatment is delayed may be found to have a progressive PIN palsy from constant pressure exerted by the dislocated radial head;
           - spontaneous recovery is usual & exploration is not indicated;


- Radiographs:
    - dislocation of radial head may be missed, eventhough frx of ulna is obvious (need AP, lateral and olbique X-rays of elbow)
    - line drawn thru radial shaft and radial head should align w/ capitellum in any position if the radial head is in normal position
         - this is esp true on the lateral projection;
    - apex of angular deformity of ulna usually indicates direction of radial head dislocation;


- Reduction:
    - immobilize the forearm in neutral rotationw/ slight supination, w/ cast carefully molded over lateral side of the ulna at the level of the fracture;
    - keep elbow flexed ( > 90 deg), to relax biceps, so that full supination can be avoided w/o losing reduction;


- Non Operative Treatment:
    - realize that even w/ successful closed reduction of the ulna (and accompanying reduction of the radial head) that subsequently there may be slow and progressive shortening and angulation;
           - hence, these patients will require close follow up;


- Treatment:
     - treated by reduction and stabilization of ulna followed by reduction of radial head via supination & direct pressure;
           - ulnar frx is treated w/ compression plate (esp in proximal third)
           - medullary nail in this location may not fill the canal and may thus provide less than rigid fixation;
     - key is to obtain length and alignment, which then allows the radial head to be reduced;
     - type I, III, and IV lesions are held in 110 deg. of flexion;
     - type II lesions with posterior dislocations should be maintained in about 70 deg. of flexion for 6 weeks;

           


- Delayed Dx:
     - when dx is delayed < 3 months, ORIF is indicated;
     - when > 3 months has elapsed, consider non operative treatment because bony ankylosis of the elbow may occur following surgery;
            - bony ankylosis may be more disabling than the joint instability
     - in child, a dislocated radial head should never be resected, since it will cause cubitus valgus, prominence of distal end of ulna, and radial deviation of head;


- Complications:
     - PIN or radial nerve palsy from anterior displacement of radial head;
           - spontaneous recovery is usual & exploration is not indicated;
           - see: nerve injuries
     - non union of frx of ulnar shaft
     - radiohumeral ankylosis
     - radioulnar synostosis
     - recurrent radial head dislocation
     - myositis ossificans



Unstable fracture-dislocations of the forearm (Monteggia and Galeazzi lesions)

Monteggia lesions in children and adults: an analysis of etiology and long-term results of treatment.

Removal of forearm plates. A review of the complications.

The posterior Monteggia lesion.

Monteggia fractures in adults: long-term results and prognostic factors

Loss of alignment after surgical treatment of posterior Monteggia fractures: salvage with dorsal contoured plating.

Monteggia fractures in adults.

Does a Monteggia variant lesion result in a poor functional outcome?: A retrospective study.

Monteggia Fractures in Pediatric and Adult Populations



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Friday, January 4, 2013 11:20 am