Human tail and myelomeningocele

A case of dumbbell-shaped accessory scrotum with concomitant lipoma

BACKGROUND

Accessory scrotum is a congenital scrotal anomaly that is usually located anterior to the anus and frequently presents with a lipoma in a bead-like shape. Herein, we present an unusual case of an accessory scrotum with a lipoma connected by a narrow stalk and located posterior to the anus.

CASE PRESENTATION

A 1-month-old boy was referred to our hospital for a perineal mass present at birth. He was born at 37 weeks and 2 days, with a birth weight of 2962 g. No abnormalities occurred during the perinatal period, and the birth was uneventful. The mass had an unusual shape, comprising two masses connected by a narrow stalk. The base of the mass was posterior to the anus and was connected to the rectal mucosa. The proximal mass was elastic and soft without skinfolds, whereas the distal mass was elastic and soft with a scrotum-like skinfolds. Magnetic resonance imaging showed no spina bifida. High-intensity adipose tissues in both masses and low-intensity vessels or fibrous stroma in cord-like structures between the two masses were found on T2-weighted images. At 3 months of age, the patient underwent resection in the prone jackknife position. No tumorous lesions were connected to the mass on the rectal and coccyx sides, and the mass was completely removed, preserving the anal sphincter. Histologically, the distal mass had characteristics of a scrotum, whereas the proximal mass was exclusively a lipoma. The connecting stalk had normal skin structures and a blood vessel with parallel-running nerve bundles. The postoperative course was uneventful, and the patient was discharged on postoperative day 6.

CONCLUSIONS

This case of accessory scrotum was unusual in its location and the presence of a stalk connecting the accessory scrotum and lipoma. The mechanism underlying accessory scrotum development remains unclear, and our report may impact the discourse regarding the embryological development of the accessory scrotum.

Atavistic and vestigial anatomical structures in the head, neck, and spine: an overview

Organisms may retain nonfunctional anatomical features as a consequence of evolutionary natural selection. Resultant atavistic and vestigial anatomical structures have long been a source of perplexity. Atavism is when an ancestral trait reappears after loss through an evolutionary change in previous generations, whereas vestigial structures are remnants that are largely or entirely functionless relative to their original roles. While physicians are cognizant of their existence, atavistic and vestigial structures are rarely emphasized in anatomical curricula and can, therefore, be puzzling when discovered incidentally. In addition, the literature is replete with examples of the terms atavistic and vestigial being used interchangeably without careful distinction between them. We provide an overview of important atavistic and vestigial structures in the head, neck, and spine that can serve as a reference for anatomists and clinical neuroscientists. We review the literature on atavistic and vestigial anatomical structures of the head, neck, and spine that may be encountered in clinical practice. We define atavistic and vestigial structures and employ these definitions consistently when classifying anatomical structures. Pertinent anatomical structures are numerous and include human tails, plica semilunaris, the vomeronasal organ, levator claviculae, and external ear muscles, to name a few. Atavistic and vestigial structures are found throughout the head, neck, and spine. Some, such as human tails and branchial cysts may be clinically symptomatic. Literature reports indicate that their prevalence varies across populations. Knowledge of atavistic and vestigial anatomical structures can inform diagnoses, prevent misrecognition of variation for pathology, and guide clinical interventions.

Congenital Spinal Lipomatous Malformations. Part 2. Differentiation from Selected Closed Spinal Malformations

BACKGROUND

Congenital spinal lipomatous malformations (spinal lipomas, lipomyeloceles, and lipomyelomeningoceles) are closed neural tube defects over the lower back. Differentiation from some other closed neural tube defects in this region can be problematic for pathologists.

MATERIALS AND METHODS

This review is based on PubMed searches of the embryology, gross and histopathologic findings, and laboratory reporting requisites for retained medullary spinal cords, coccygeal medullary vestiges and cysts, myelocystoceles, true human vestigial tails, and pseudotails for comparison with congenital spinal lipomatous malformations.

RESULTS

Embryology, imaging, gross and histopathology of these closed neural tube lesions have different but overlapping features compared to congenital spinal lipomatous malformations, requiring context for diagnosis.

CONCLUSION

The lipomyelocele spectrum and to some degree all of the malformations discussed, even though they may not share gross appearance, anatomic site, surgical approach, or prognosis, require clinical and histopathologic correlation for final diagnosis.

Limited dorsal myeloschisis with a contiguous stalk to human tail-like cutaneous appendage, associated with a lipoma of conus medullaris: A case report

INTRODUCTION

Limited dorsal myeloschisis (LDM) is a recently described pathological entity, characterized by a defect of the closed focal neural tube and a fibroneural pedicle connecting the cutaneous lesion to the spinal cord.

PRESENTATION OF THE CASE

This case describes a 9-month-old child with a human tail and an underlying spinal dysraphism. This was represented by LDM stalk associated with a medullary lipoma, in connection with the dorsal cutaneous appendage. We also report the therapeutic proposal for this case and its clinical outcome.

DISCUSSION

LDM is a distinctive clinicopathological presentation of a spinal dysraphism, associated with numerous anomalies, such as lipomyelomeningocele, tethered cord, lipoma, congenital heart disease and teratoma. In this case, surgical treatment for LDM consists of surgical resection of the appendage, untethering of the spinal cord and resection of conus medullaris lipoma in the same procedure.

CONCLUSION

In this case report, we share the experience of a referral service in pediatric neurosurgery regarding clinical and radiological diagnosis, and the successful treatment of this rare type of congenital malformation. Therefore, clinicians should be aware of possible morphological variations of the skin lesion associated with LDM.

Human Tail: A Benign Condition Hidden Out of Social Stigma and Shame in Young Adult - A Case Report and Review

A human tail is a rare congenital anomaly which mostly presents immediately after birth or in early childhood. Here, we are presenting a case of 17-year-old male who presented with 18-cm long tail, which was hidden till this age because of social stigma and shame. This is longest human tail reported of our knowledge. This patient presented to us because he started having difficulty, pain while sitting, and discomfort in daily activities because of long tail. We suspect there are far more cases of human tails in developing world which are hidden because of lack of knowledge, illiteracy, social stigma, and shame. This patient had no neurological deficit and had no bowel/bladder involvement. The radiological investigation was suggestive of spina bifida at L₅ and S3–S4 levels (site of attachment of the tail), and tip of the coccyx had bony spur directed posteriorly. Intraoperatively, no connection was found between tail and neural tissue. Human tail is associated with occult spinal lesions in 50% of cases, hence careful neurological and radiological investigations are warranted before surgical exploration.

Myelomeningocele closure by unilateral lumbar artery perforator flap: Experience with thirty-eight patients

BACKGROUND

Repair of large soft tissue defects in meningomyelocele is difficult and its morbidity is high. By applying unilateral lumbar artery perforator transposition flap for closing these defects, we aimed to investigate effects on the repair procedure, duration of surgery and recovery period, with the rates of bleeding and morbidity.

PATIENTS AND METHODS

Our report was conducted in 38 patients between the years 2013 and 2017. All soft tissue defects were repaired with unilateral lumbar artery perforator flap (LAPF) in meningomyelocele. Fourteen patients were female and 24 patients were male. The youngest patient was a 5.5 month premature female baby and weighing 570 g. The oldest was weighing 3,700 g and at 1.5 months old.

RESULTS

Mean flap size was 32 ± 29.4 cm² (ranged: 4 × 3-8 × 7 cm² ). The mean rotation angle was 126.7° (ranged: 90°-170°). Flap positions were separated as 9 (23%) thoracodorsal and 29 (77%) lumbosacral. None of the patients had flap necrosis, infection, or hematoma. The operation took 23 ± 5.3 minutes on average and bleeding was minimal as 16 cc. All patients were discharged within around 9 ± 2 days. The follow-up period of the patient ranged from 4 to 21 months. Flap survival was at the rate of 100%. There was no flap or postoperative complications. Final outcome for all patients were assessed as complete healing. All patients recovered fast with minimal blood lose, and satisfied the outcomes.

CONCLUSIONS

As a result, unilateral lumbar perforator flap can be performed successfully in every center. This report suggests using LAPF for reconstruction of meningomyelocele by surgeons as a safe and reliable option, allowing surgeons strong results.

Proposed caudal appendage classification system; spinal cord tethering associated with sacrococcygeal eversion

INTRODUCTION

The most commonly used classification system for caudal appendages (aka human tails) dates from the 1980s and classifies appendages (tails) as either true tails or pseudotails. Advances in neuroimaging since the 1980s, however, as well as an ever-increasing number of reported cases, have made this system outdated. Sacrococcygeal eversion is a condition in which the distal sacral and coccygeal vertebrae are curved in a retroverted rather than anteverted direction. It can give rise to one type of caudal appendage. Sacrococcygeal eversion has never been associated with spinal cord tethering in any previously published reports.

METHODS

We reviewed all cases of caudal appendage encountered by pediatric neurosurgeons at Children's Hospital Colorado since 2000 in which the appendage would be classified as a true tail by the most commonly used system mentioned above. We also reviewed cases of sacrococcygeal eversion encountered since 2000 by the same group of pediatric neurosurgeons. We searched the hospital electronic medical record system for additional appendages using the terms "caudal appendage" and "persistent human tail."

RESULTS

We found 9 "true" tails (as classified by the most commonly used system). All 9 were associated with tethering or possible tethering of the spinal cord and 6 were associated with a low-lying conus medullaris. There were 8 cases of sacrococcygeal eversion, including 2 associated with Apert or Pfeiffer syndrome and fibroblast growth factor receptor 2 (FGFR2) mutations; these have previously been reported. There was a single case of sacrococcygeal eversion associated with Goldenhar or Turner syndrome; the former was associated with a potentially tethering lesion. Four cases of sacrococcygeal eversion not associated with any known syndrome were also found; two of these were associated with tethering or potentially tethering lesions.

CONCLUSIONS

Most so-called true tails are likely cutaneous markers for spinal dysraphism and spinal cord tethering and are not remnants of the embryonic human tail. Sacrococcygeal eversion can be associated with spinal cord tethering. Based on our cases, and on review of the literature, we devised a five-category classification system for caudal appendages: (1) soft-tissue caudal appendages, (2) bony caudal appendages, (3) bony caudal prominences, (4) true tails, and (5) "other" caudal appendages.

Enigmatic human tails: A review of their history, embryology, classification, and clinical manifestations

The presence of a human tail is a rare and intriguing phenomenon. While cases have been reported in the literature, confusion remains with respect to the proper classification, definition, and treatment methods. We review the literature concerning this anatomical derailment. We also consider the importance of excluding underlying congenital anomalies in these patients to prevent neurological deficits and other abnormal manifestations.

A gelatinous human tail with lipomyelocele: case report

We report a female infant who presented with a tail appendage bearing a gelatinous tip and an associated lipomyelocele. Magnetic resonance images revealed the presence of spina bifida and a tract in continuity from the tail to the conus medullaris. The tail was surgically removed. A human tail may be associated with underlying spinal dysraphism. Magnetic resonance or computed tomographic imaging is required in such cases for complete evaluation. This is the first case report of gelatinous-tip human tail.

Retained medullary cord in humans: late arrest of secondary neurulation

BACKGROUND

Formation of the caudal spinal cord in vertebrates is by secondary neurulation, which begins with mesenchyme-epithelium transformation within a pluripotential blastema called the tail bud or caudal cell mass, from thence initiating an event sequence proceeding from the condensation of mesenchyme into a solid medullary cord, intrachordal lumen formation, to eventual partial degeneration of the cavitatory medullary cord until, in human and tailless mammals, only the conus and filum remain.

OBJECTIVE

We describe a secondary neurulation malformation probably representing an undegenerated medullary cord that causes tethered cord symptoms.

METHOD

We present 7 patients with a robust elongated neural structure continuous from the conus and extending to the dural cul-de-sac, complete with issuing nerve roots, which, except in 2 infants, produced neurological deficits by tethering.

RESULTS

Intraoperative motor root and direct cord stimulation indicated that a large portion of this stout neural structure was "redundant" nonfunctional spinal cord below the true conus. Histopathology of the redundant cord resected at surgery showed a glioneuronal core with ependyma-lined lumen, nerve roots, and dorsal root ganglia, corroborating the picture of a blighted spinal cord.

CONCLUSION

We propose that these redundant spinal cords are portions of the medullary cord normally destined to regress but are here retained because of late arrest of secondary neurulation before the degenerative phase. Because programmed cell death almost certainly plays a central role during degeneration, defective apoptosis may be the underlying mechanism.

Spinal cord tethering by aberrant nerve root in myelomeningocele: case report

INTRODUCTION

A 2,796-gram male baby was born at 40 weeks gestation by vaginal delivery. Soon after, he was admitted at our department for treatment of a dorsal appendage.

RESULTS AND DISCUSSION

Magnetic resonance (MR) imaging showed a low-position spinal cord, skin-covered myelomeningocele, syringomyelia, and a tethered cord. Resection of the caudal appendage and tethering tissue was performed 22 days after birth under electrophysiological monitoring. Histopathological examination of the caudal appendage that was covered with skin revealed the presence of spinal cord tissue and peripheral nerve tissue. The string-like tethering tissue that extended from the spinal cord to the caudalis was a nerve root, and there was fiberization of the caudalis. The syringomyelia was improved at postoperative MR imaging. To our knowledge, there is no report of a similar case in the literature. We report rare combination of myelomeningocele and spinal cord tethering by aberrant nerve root with thoracic syringomyelia.

Coexistence of a human tail and congenital dermal sinus associated with lumbosacral lipoma

We present a female baby with a human tail associated with congenital dermal sinus (CDS) at the caudal site of the tail. Magnetic resonance (MR) images with constructive interference in steady-state (CISS) sequencing clearly demonstrated a lumbosacral lipoma of caudal type, contiguous with the dermal sinus tract and not with the human tail. At 3 months old, the tail was surgically removed. The dermal sinus tract and contiguous lipoma were also resected, and untethering of the spinal cord was performed. Although both the human tail and CDS are frequently associated with spina bifida occulta, coexistence of the tail and CDS is exceedingly rare. CISS-MRI is useful for demonstrating the precise anatomical relationship between these complicated pathologies.