Vestigial human tail and occult spinal dysraphism: A case report.

Background: The presence of a human tail is a rare condition resulting from an embryonic remnant that fits the definition of a caudal appendage. It may be a vestigial (true) or a pseudotail. Both may be considered markers of underlying intraspinal abnormalities.

Case description: The present case documents a 5-year-old girl with a caudal appendage in the lumbar region, with a previously normal neurological examination. Spinal magnetic resonance imaging (MRI) showed the presence of occult spinal dysraphism associated with a cutaneous appendage with lipomatous content. We performed microsurgical treatment to excise the lesion and explore the occult spinal dysraphism. A histopathological examination revealed mature adipose tissue with blood vessels and nerve fibers and no bone or cartilage tissue.

Conclusion: The presence of a tail-like appendage in the lumbosacral region must alert to the possibility of underlying occult spinal dysraphism. Preoperative assessment must include a complete neurological examination and a detailed MRI evaluation.