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  • Imaging Casebook
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Imaging Case Book

Human tail–caudal appendage: tethered cord

Journal of Perinatology volume 28, pages 518–519 (2008)Cite this article

The sonogram and MRI demonstrate a tethered cord with a lipoma of the filum and a fibro-fatty caudal appendage or human tail posterior. The child has been referred to a neurosurgeon for cord untethering and resection of the caudal appendage and lipoma. Human tail is an anomaly mentioned rarely but intermittently throughout history; cases have been described by both Marco Polo and Christopher Columbus.1 Caudal appendages or human tails were divided by Dao and Netsky into true tails, which contain muscle and are movable, and pseudotails, which do not move. However, this is now considered arbitrary and without clinical significance as both kinds are derived from notocordal remnants and the etiology of both is probably similar.2 Most human tails are tubular structures of mature adipose tissue and fibrous tissue containing normal blood vessels, but usually are neither muscles nor bones. These structures usually occur in the midline or just off midline in the sacro-coccygeal region. They have been reported to vary between 1 and 20 cm in length.2 Their etiology is probably related to an abnormal sequence of caudal neurulation,1 and so they have also been called neuroectodermal appendages.3 As of 1997, approximately 59 cases of human tail had been described in the medical literature. Forty-nine percentage of these were associated with spinal dysraphism; 81% of those who had an MRI had a tethered cord. Symptoms related to cord tethering including ambulatory, genitourinary and bowel problems may not occur until the third decade of life in patients with human tails and spinal dysraphism.3

Caudal appendages also occur as typical or frequent manifestations of certain syndromes. Very little imaging or surgical evidence exists about the frequency of tethered cord in these syndromes, which often limits the life expectancy of the patient. These syndromes include Frank-ter Haar syndrome, an autosomal recessive condition with skeletal findings similar to Melnick–Needles syndrome but with distinctive ocular and cardiac findings, Pallister–Killian syndrome (isochromosome 12p), metatropic dysplasia, Kabuki facies syndrome and the probably genetically related Teebi–Shaltout syndrome and Malpuech syndrome (cleft palate and urogenital anomalies).4 Caudal appendages have also been described in craniosynostosis patients associated with FGFR2 (fibroblast growth factor receptor 2) gene mutations.5

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References

  1. Gonul E, Izci O, Onguru O, Timurkaynak E, Seber N . The human tail associated with intraspinal lipoma: case report. Min Invasive Neurosurg 2000; 43: 215–218.

    Article  CAS  Google Scholar 

  2. Donovan DJ, Pedersen RC . Human tail with noncontiguous intraspinal lipoma and spinal cord tethering: case report and embryologic discussion. Pediatr Neurosurg 2005; 41: 35–40.

    Article  Google Scholar 

  3. Ersahin Y, Gezen F, Baysefer A, Beduk A . Neuroectodermal appendage; a case report and review. Turkish Neurosurg 1993; 3: 25–27.

    Google Scholar 

  4. Kerstjens-Frederikse WS, Brunner HG, van Dael CML, van Essen AJ . Malpuech syndrome; 3 patients and a review. Am J Med Genetics 2005; 134a: 450–453.

    Article  Google Scholar 

  5. Sweeney E, Ellis I, May P . Sacral appendage associated with a mutation in FGFR2. Clin Dysmorphol 2002; 11: 221–222.

    Article  Google Scholar 

  6. Lowe LH, Johanek AJ, Moore CW . Sonography of the neonatal spine: part I, normal anatomy, imaging pitfalls and various that may simulate disorders. AJR Am J Roentgenol 2007; 188: 733–783.

    Article  Google Scholar 

  7. Lowe LH, Johanek AJ, Moore CW . Sonography of the neonatal spine: part 2, spinal disorders. AJR Am J Roentgenol 2007; 188: 739–744.

    Article  Google Scholar 

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  1. Department of Radiology, St Louis Children's Hospital, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA

    T E Herman & M J Siegel

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  1. T E Herman
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  2. M J Siegel
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Correspondence to T E Herman.

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Herman, T., Siegel, M. Human tail–caudal appendage: tethered cord. J Perinatol 28, 518–519 (2008). https://doi.org/10.1038/jp.2008.39

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