Ultrasonographic swelling ratio in the diagnosis of ulnar neuropathy at the elbow.
High-resolution ultrasound can demonstrate focal nerve enlargement in entrapment neuropathies. We hypothesized that a ratio between the nerve cross-sectional area at the site of maximal enlargement and at an unaffected site may improve diagnostic accuracy in ulnar neuropathy at the elbow (UNE), when compared to a single measurement at the site of maximal enlargement. Ultrasound was used to measure the cross-sectional area of the ulnar nerve at three sites in 30 normal, healthy controls and 26 individuals with UNE. In individuals with UNE, the ratio was 2.9:1 when the site of maximal swelling was compared with a distal ulnar nerve site and 2.8:1 when compared with a proximal site. This represented a significant increase compared with the ratio of 1.1:1 for both comparisons in controls (P < 0.0001). This type of ratio may be particularly useful for assessing entrapment in those with polyneuropathy or obesity, both of which can cause diffuse nerve enlargement.
Yoon
Joon Shik
JS
Department of Physical Medicine and Rehabilitation, Korea University College of Medicine, Seoul, South Korea.
Walker
Francis O
FO
Cartwright
Michael S
MS
D000328:Adult; D000367:Age Factors; D015984:Causality; D020430:Cubital Tunnel Syndrome / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D004487:Edema / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D004550:Elbow / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D011115:Polyneuropathies / Q000150:complications; D012720:Severity of Illness Index; D014459:Ulnar Nerve / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D014463:Ultrasonography / Q000379:methods*