Sonographic diagnosis of acute injuries of the ulnar collateral ligament of the metacarpophalangeal joint of the thumb.
OBJECTIVE
To evaluate the significance of the ultrasonographic appearance of the aponeurosis for deciding the best treatment for ulnar collateral ligament (UCL) injuries of the thumb metacarpophalangeal joint.


METHODS
Fourteen patients (11 men, 3 women; mean age, 41 years; range, 15-66 years) who had an acute UCL tear were included. All patients were examined by ultrasonography (US) with a 7.5-MHz transducer and subsequently underwent surgery. The ultrasonographic findings were compared to the intraoperative findings.


RESULTS
UCL injuries were classified into two types by US according to the appearance of aponeurosis and its spatial relationship with the UCL: the intra-aponeurosis type (5 patients) and the extra-aponeurosis type (9 patients). In the 5 patients with intra-aponeurosis, ultrasonographic findings were well consistent with intraoperative findings. In contrast, extra-aponeurosis cases contained two different pathologies: of the 9 patients, 7 had so-called 'Stener lesions', one showed folding of a ruptured capsule, and one showed a ruptured aponeurosis.


CONCLUSIONS
Because US is highly reliable in differentiating intra-aponeurosis from extra-aponeurosis types of injuries, the aponeurosis is a more reliable reference than Stener lesion for treatment decision by US.
Shinohara
Takaaki
T
Department of Hand Surgery, Nagoya University School of Medicine, Nagoya 466-8550, Japan.
Horii
Emiko
E
Majima
Masataka
M
Nakao
Etsuhiro
E
Suzuki
Masataka
M
Nakamura
Ryogo
R
Hirata
Hitoshi
H
D000293:Adolescent; D000328:Adult; D000368:Aged; D017885:Collateral Ligaments / Q000000981:diagnostic imaging* / Q000293:injuries* / Q000601:surgery; D005260:Female; D005383:Finger Injuries / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D008297:Male; D008662:Metacarpophalangeal Joint / Q000000981:diagnostic imaging* / Q000293:injuries* / Q000601:surgery; D008875:Middle Aged; D013933:Thumb / Q000000981:diagnostic imaging* / Q000293:injuries* / Q000601:surgery; D014457:Ulna / Q000000981:diagnostic imaging; D014463:Ultrasonography