During the 5th and 6th week of gestation, the human embryo possess a tail with 10 -12 caudal vertebrae which regresses by reduction in the number of vertebrae and fusion, leaving the vestigial coccyx. Hence, the true human tail is a vestigial structure and never contains vertebrae. It has been suggested that true tail is a dermal appendage coincidentally located in the sacrococcygeal region and can be located 1.5 cm to one side of the midline.. Rarely, a child is born with a “soft tail” containing blood vessels, muscles and nerves but without vertebral bones which are the pseudo-tails (lipoma, teratoma, myelomeningocele and parasitic fetus).
Careful investigation should be undertaken prior to embarking upon a surgical procedure. The caudal appendage is not a medical difficulty to treat. But before the choice of the manner of treatment, it is necessary to evaluate the patient carefully in case of coexisting with the lesions of intraspinal component.
Pictures submitted by Dr. Esana Pokhrel, KISTMC