Anterior horn of the lateral meniscus: another potential pitfall in MR imaging of the knee.
OBJECTIVE
To demonstrate that speckled increased signal intensity at the anterior horn of the lateral meniscus near its central attachment site on sagittal magnetic resonance (MR) images of the knee is a normal finding.


METHODS
In 22 patients (17 male and five female patients; age range, 13-74 years; mean, 38 years) who underwent arthroscopy after MR imaging, knee MR images that showed speckled increased signal intensity at the anterior horn of the lateral meniscus near its central attachment site on two consecutive sagittal proton-density-weighted images were selected for retrospective review. In addition, a review of 11 knee MR examinations of nine healthy volunteers (five men and four women; age range, 27-43 years; mean, 34 years) was performed.


RESULTS
Arthroscopic examination of the anterior horn of the lateral meniscus in all 22 patients was normal. Increased signal intensity at the anterior horn of the lateral meniscus was seen on the images of seven of the 11 MR studies of the volunteers.


CONCLUSIONS
Increased signal intensity at the anterior horn of the lateral meniscus near its central attachment site on knee MR images does not represent a meniscal tear.
Shankman
S
S
Department of Radiology, Hospital for Joint Diseases, New York, NY 10003, USA.
Beltran
J
J
Melamed
E
E
Rosenberg
Z S
ZS
D000293:Adolescent; D000328:Adult; D000368:Aged; D001182:Arthroscopy; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000592:standards*; D008297:Male; D008592:Menisci, Tibial / Q000033:anatomy & histology / Q000473:pathology*; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D000070600:Tibial Meniscus Injuries; D014947:Wounds and Injuries / Q000175:diagnosis / Q000601:surgery