Ulnar Translocation



- Discussion:
    - most frequent radiocarpal instability;
    - the lunate is translocated ulnarly, and therefore is not supported by the radius;
    - ulnar translationn is also commonly seen in disease such as RA or in Madelung's deformity;
            - in RA, may occur along w/ caput ulnae syndrome;
    - abnormal translation of lunate in ulnar direction is pathognomonic of ulnar translocation;

- Clinical Presentation:
    - clinically the carpus and hand are offset ulnarward;

- Radiographs:
     - on x-ray, lunate is positioned just distal to the ulna and a large space between the radial styloid and the scaphoid;
     - two types according to position of scaphoid:
            - Type I:
               - entire carpus, including scaphoid, is displaced, & distance between radial styloid process & scaphoid is widened;
            - Type II:
                   - distance between scaphoid & radial styloid process, remains normal, but the scapholunate space is widened;
            - it's important to distinguish between the two types of ulnar translocation since appearance of a wide scapholunate gap may lead to the erroneous dx of scapholunate dissociation;

- Treatment:
    - late identification of ulnar translation deformity or dorsal or volar translation deformity reponds poorly to ligament repairs;
    - acutely consider, radiolunate fusion;
    - consider relocation of carpus & maintenance of reduction by radiolunate arthrodesis may be a more reliable and satisfactory technique;
    - Darrah's Procedure:
         - the main limitation with this procedure in the rheumatoid wrist, is that there is nothing to prevent continued ulnar and palmar translocation of the carpus;
    - Sauve Kapandji Procedure:
         - may allow a higher level of wrist function than is seen w/ the Darrah procedure



Irreducible fracture-dislocation of the distal radioulnar joint secondary to entrapment of the extensor carpi ulnaris tendon.

Congenital radio-ulnar synostosis: surgical treatment.

The Sauvé-Kapandji procedure.

Post Traumatic Ulnar Translocation of the Carpus. Rayhack JM, et al. J Hand Surg. 1987;12-A:180-189.



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

Last updated by Data Trace Staff on Wednesday, December 12, 2012 12:23 pm