- See:
-
PA View of the Wrist:
-
X-ray findings: in scapholunate dislocation:
- Discussion:
- used to evaluate widening of scapholunate interval;
- those pts suspected of having
SLD should have compression stress view, which is performed by having pt clench his fist for
AP film;
- clenching first draws capitate proximally & emphasizes any widening of scapho-lunate interval;
- should get companion views of the opposite side for comparison;
- best taken: w/
supinated clenched fist view w/ wrist in
ulnar deviation;
-
AP x-rays made w/ wrist in ulnar deviation (increases gap), in radial deviation (decreases gap), & w/ application of longitudinal compressive load
(clenched fist) may also show widened scapholunate gap in wrist w/ SLD;
- Technique:
- same technique as
PA view of wrist except patient clenches fist as tightly as possible during exposure;
- proper technique: for visualizing scapholunate interval;
- gap is more noticeable on
AP View that is made w/ wrist supinated than it is on more usual PA view (made w/ wrist pronated);
- Findings in Scapholunate Dissociation
-
scapholunate interval > 2-3 mm (Terry Thomas sign);
-
cortical ring sign:
- produced by cortex of distal pole of palmar flexed scaphoid;
- produced by cortical outline of the distal pole of scaphoid;
-
scaphoid is foreshortened;
- distance between scaphoid ring & proximal pole is < 7 mm;
-
negative ulnar variance:
- misc:
- ulnar deviation, increases scapholunate gap;
- radial deviation, closes gap;
The “clenched pencil” view: A modified clenched fist scapholunate stress view
