Sonography of the normal scapholunate ligament and scapholunate joint space.
OBJECTIVE
The aims of this study were to assess the visibility of the normal scapholunate ligament on sonography and to establish the normal scapholunate joint space width in the neutral position and radial and ulnar deviation.


METHODS
Two hundred normal wrists in 100 subjects (55 men and 45 women; mean age, 40 years; range, 19-83 years) were examined with high-resolution sonography (5-12-MHz linear-array transducer). The visibility and thickness of the scapholunate ligament were recorded. The width of the scapholunate joint space, or interval, was measured in the neutral position and radial and ulnar deviation. The width of the distal radius was recorded as a comparative standard for the patients' body habitus.


RESULTS
The dorsal scapholunate ligament was completely (100%) visible in 95 wrists (48%), partially (> or = 50%) visible in 60 (30%), barely (< 50%) visible in 15 (8%), and not visible in 30 (15%). The volar scapholunate ligament was completely visible in 13 wrists (7%), partially visible in 17 (9%), barely visible in 15 (8%), and not visible in 151 (76%). The proximal component of the ligament was not visible in any subject. Measurement of the scapholunate interval was limited by the lack of identifiable anatomic marks for reference. The mean width of the dorsal scapholunate interval was 4.2 mm (range, 2.3-6.3 mm) in the neutral position. The interval did not differ more than 2.5 mm between the left and right wrists. No predictable change in width on ulnar or radial deviation was evident. The mean scapholunate intervals and mean distal radial width were significantly wider in men than in women and on the right side than on the left side.


CONCLUSIONS
The dorsal scapholunate ligament is completely or partially visible in 78% of normal wrists. Its detection following injury may help to exclude the possibility of scapholunate dissociation. There is a quite wide variation in scapholunate interval widths on sonography and an unpredictable response with stress testing. The absence of a visible scapholunate ligament on sonography does not indicate injury.
Griffith
J F
JF
Department of Diagnostic Radiology and Organ Imaging, Chinese University of Hong Kong, Prince of Wales Hospital, Sha Tin, New Territories, Hong Kong.
Chan
D P
DP
Ho
P C
PC
Zhao
L
L
Hung
L K
LK
Metreweli
C
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry; D002348:Carpal Bones; D005260:Female; D006801:Humans; D008023:Ligaments, Articular / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011884:Radius / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D012016:Reference Values; D014457:Ulna / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D014463:Ultrasonography; D014953:Wrist / Q000033:anatomy & histology / Q000000981:diagnostic imaging*