The human tail is a relatively rare anatomical curiosity. Once a subject of controversy concerning its evolutionary import,1 it remains an intriguing developmental anomaly today. The main clinical importance lies in the distinction of a human tail from more significant sacrococcygeal lesions, such as meningomyelocele, sacrococcygeal glioma, and teratoma. Few cases have been documented after careful histologic study, and it is likely that many of the earlier cases 1 represented these other lesions.
In his definitive embryologic study, Harrison postulated that the human tail resulted from persistence of the vestigial tail, usually the nonvertebral portion (caudal filament), of the 14-16 mm. embryo.2 It is probable that no tails containing an increased number of coccygeal vertebrae, representing Bartel's "true atavistic tail,"3 have been reported. This case represents the second human tail recorded in the American literature since 1929.4
Report of a Case
The patient was a Caucasian