Prenatally diagnosed human caudal appendage: a case report.
BACKGROUND
The caudal appendage, or human tail, is a rare congenital anomaly that arises from the lumbosacrococcygeal region.


METHODS
A pregnant woman was referred after ultrasound revealed a possible neural tube defect. A sonogram in our unit revealed a posterior, echogenic protrusion superior to the fetal buttocks. Examination of the infant revealed a fetal caudal appendage at the level of S-4. Ultrasound imaging of the neonatal spine demonstrated a tethered spinal cord extending to the level of S-4 and exiting toward the caudal appendage.


CONCLUSIONS
A fetal caudal appendage should be included in the differential diagnosis of an echogenic protrusion near the lumbosacral spine on ultrasound. The finding of a caudal appendage in a neonate mandates a careful search for an underlying spinal cord defect.
Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, Missouri 63110, USA. wrightj@msnotes.wustl.edu
Jason D
JD
Wright
Sara J
SJ
Marder
Sajeena
S
Geevarghese
Joseph B
JB
Shumway
D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D009139:Musculoskeletal Abnormalities / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery; D009436:Neural Tube Defects / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery; D011247:Pregnancy; D012445:Sacrococcygeal Region; D016216:Ultrasonography, Prenatal