“Human tail”: Case reports of coccyx retroposition in children

Cover Page


Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription or Fee Access

Abstract

BACKGROUND: A “human tail” is a rare congenital malformation that corresponds to the protrusion on the dorsal side of the lumbar, sacrococcygeal, and paraanal regions. This study aimed to demonstrate three rare clinical cases of a tail-shaped formation caused by the protrusion of an elongated coccyx in children.

CLINICAL CASES: These patients asked for medical assistance for pain felt in the sitting position and daily discomfort because this formation barely contains any tissues other than the coccyx. The patients had no signs of neurological and lower urinary tract insufficiency. In all cases, the retroposition of the coccyx without its typical anterior angulation was determined based on radiographic and magnetic resonance imaging (MRI) signs. In one case, the coccyx was represented by four elongated vertebrae without a typical decrease in the size of the vertebrae in the caudal direction. In two cases, an angular deformity of the coccyx occurred at the level of CoIII with intercoccygeal angles of 138° and 140°.

DISCUSSION: The tail-like formations could be classified as “pseudo-tails” according to the classification by Dao and Netsky (1984) and type Ia “human tails” according to the classification by Tojima and Yamada (2020).

CONCLUSIONS: The most important feature of tail-shaped formation is the connection with occult dysraphic malformations, which requires a comprehensive preoperative examination in each case (neurological examination, radiography, computed tomography, and MRI). Careless surgery may lead to serious consequences that significantly impair patients’ quality of life.

Full Text

Restricted Access

About the authors

Svetlana I. Trofimova

H. Turner National Medical Research Center for Children’s Orthopedics and Trauma Surgery

Email: trofimova_sv2012@mail.ru
ORCID iD: 0000-0003-2690-7842
SPIN-code: 5833-6770
Scopus Author ID: 57193275907

MD, PhD, Cand. Sci. (Med.)

Russian Federation, Saint Petersburg

Dmitry S. Buklaev

H. Turner National Medical Research Center for Children’s Orthopedics and Trauma Surgery

Email: dima@buklaev.com
ORCID iD: 0000-0003-1868-3703
SPIN-code: 4640-6856

MD, PhD, Cand. Sci. (Med.)

Russian Federation, Saint Petersburg

Tatiana V. Murashko

H. Turner National Medical Research Center for Children’s Orthopedics and Trauma Surgery

Author for correspondence.
Email: popova332@mail.ru
ORCID iD: 0000-0002-0596-3741
SPIN-code: 9295-6453

MD, radiologist

Russian Federation, Saint Petersburg

References

  1. Dao AH, Netsky MG. Human tails and pseudotails. Hum Pathol. 1984;15(5):449–453. doi: 10.1016/s0046-8177(84)80079-9
  2. Giri PJ, Chavan VS. Human tail: a benign condition hidden out of social stigma and shame in young adult – a case report and review. Asian J Neurosurg. 2019;14(1):1–4. doi: 10.4103/ajns.AJNS_209_17
  3. Hamoud K, Abbas J. A tale of pseudo tail. Spine. 2011;36(19):E1281–E12814. doi: 10.1097/BRS.0b013e31820a3dd9
  4. Lin PJ, Chang YT, Tseng HI, et al. Human tail and myelomeningocele. Pediatr Neurosurg. 2007;43(4):334–337. doi: 10.1159/000103318
  5. Cai C, Shi O, Shen C. Surgical treatment of a patient with human tail and multiple abnormalities of the spinal cord and column. Adv Orthop. 2011;2011. doi: 10.4061/2011/153797
  6. Tojima S, Yamada S. Classification of the “human tail”: Correlation between position, associated anomalies, and causes. Clin Anat. 2020;33(6):929–942. doi: 10.1002/ca.23609
  7. Katsuno S, Horisawa M. A case of perianal human tail. J Jpn Soc Pediatr Surg. 2008;44:808–813.
  8. Saka R, Hasegawa T, Sonobe H. A case of perianal human tail. Journal of Japanese College of Surgeons. 2010;35:85–88.
  9. Falzoni P, Boldorini R, Zilioli M, et al. The human tail. Report of a case of coccygeal retroposition in childhood. Minerva Pediatr. 1995;47(11):489–491.
  10. Mohammad Bashir, Davlicarov MA, Cybin AA, et al. Istinnyj hvost s distal’nym udvoeniem u novorozhdennogo. Detskaya hirurgiya. 2015;19(4):53–54. (In Russ.)
  11. Wilkinson CC, Boylan AJ. Proposed caudal appendage classification system; spinal cord tethering associated with sacrococcygeal eversion. Childs Nerv Syst. 2017;33(1):69–89. doi: 10.1007/s00381-016-3208-x
  12. Ersahin Y, Gezen F, BedÜk AB. Neuroectodermal appendage: a case report and review. Turkish Neurosurgery. 1993;3:25–27.
  13. Iqbal Z, Cejudo-Martin P, de Brouwer A, et al. Disruption of the podosome adaptor protein TKS4 (SH3PXD2B) causes the skeletal dysplasia, eye, and cardiac abnormalities of Frank-Ter Haar syndrome. Am J Hum Genet. 2010;86(2):254–261. doi: 10.1016/j.ajhg.2010.01.009
  14. Sirmaci A, Walsh T, Akay H, et al. MASP1 mutations in patients with facial, umbilical, coccygeal, and auditory findings of Carnevale, Malpuech, OSA, and Michels syndromes. Am J Hum Genet. 2010;87(5):679–686. doi: 10.1016/j.ajhg.2010.09.018

Supplementary files

Supplementary Files
Action
1. JATS XML
Download
2. Fig. 1. Appearance of the tail-like formation

Download (63KB)
Indexing metadata
3. Fig. 2. X-ray imaging of the sacrococcygeal spine in the lateral view: atypical position of the caudal spine (coccyx retroposition)

Download (46KB)
Indexing metadata
4. Fig. 3. Comparison of the vertebrae of the sacrococcygeal spine of the patient (a, c) with the “age norm” (b, d) on the midsagittal image using volume imaging. Elongation of vertebrae SIV, SV, CoI, CoII, and CoIII, and absence of a typical gently-sloping kyphosis of the posterior vertebral line at the level of the sacrum from the SIV level

Download (184KB)
Indexing metadata
5. Fig. 4. Computed tomography. Reconstruction of the sacrococcygeal spine, sagittal view: posterior angulation of the coccyx, intercoccygeal angle of 138°

Download (93KB)
Indexing metadata
6. Fig. 5. Computed tomography. Reconstruction of the sacrococcygeal spine, sagittal view (a), axial view (b), and volume imaging (c). Additional bone fragment of the prevertebral region at the CoI–II level

Download (185KB)
Indexing metadata
7. Fig. 6. Tail formation

Download (46KB)
Indexing metadata
8. Fig. 7. X-ray imaging of the sacrococcygeal spine in the lateral view. The sacrococcygeal angle is 150°, and the angle is open anteriorly. The coccyx is retropositioned and straightened and is represented by atypical IV vertebrae with elongation without size reduction in the caudal direction. Plus-tissue symptom was noted

Download (53KB)
Indexing metadata
9. Fig. 8. X-ray imaging of the sacrococcygeal spine in the lateral view after coccyx removal

Download (39KB)
Indexing metadata
10. Fig. 9. View of the tail formation

Download (48KB)
Indexing metadata
11. Fig. 10. X-ray imaging of the sacrococcygeal spine in the lateral view (a). Computed tomography. Reconstruction of the sacrococcygeal spine, volumetric imaging (b), and sagittal view (c): atypical position of the coccyx (retroposition, posterior angulation, and intercoccygeal angle of 140°)

Download (155KB)
Indexing metadata
12. Fig. 11. Magnetic resonance (MR) imaging in the T2-weighted imaging mode. Sagittal image (a): angular deformity of the coccyx with posterior displacement of CoIV. Axial images in fat suppression mode (b): hyperintense MR signal at the level of the caudal vertebrae from the posteriorly displaced CoIV vertebra (trabecular edema of the adjacent soft tissues on the left)

Download (123KB)
Indexing metadata
13. Fig. 12. X-ray imaging of the sacrococcygeal spine in the lateral view after coccyx removal (a) and gross specimen of the coccyx in the posterior view (b)

Download (107KB)
Indexing metadata

Copyright (c) 2023 Эко-Вектор


СМИ зарегистрировано Федеральной службой по надзору в сфере связи, информационных технологий и массовых коммуникаций (Роскомнадзор).
Регистрационный номер и дата принятия решения о регистрации СМИ: серия ПИ № ФС77-54261 от 24 мая 2013 г.


This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies