Human tail with noncontiguous intraspinal lipoma and spinal cord tethering: case report and embryologic discussion

Thoracic bony human tail in a newborn baby: a rare case and review of literature

BACKGROUND

The dorsal cutaneous appendage or so-called human tail is considered to be a cutaneous marker of underlying occult dysraphism.

CASE PRESENTATION

We are presenting an unusual case of spinal dysraphism with a bony human tail at midthoracic region occurring in a newborn baby with tethered cord (conus at L4). Physical examination was unremarkable except for a thoracic appendage and a dermal sinus over coccyx region. Magnetic resonance imaging (MRI) scan of spine revealed bony outgrowth arising from D7 posterior element with multiple butterfly-shaped vertebrae found at D2 D4 D8 D9 D10 with low-lying conus at L4-L5 level. Surgical excision of the tail and untethering of the spinal cord along with excision of dermal sinus were performed. The infant had an uneventful postoperative period and was unchanged neurologically.

CONCLUSION

To our knowledge, no similar case has been reported in English literature till date.

DISCUSSION

The specific features of this rare case of human tail treated surgically are discussed in light of the available literature.

Pseudotail with closed neural tube defect and neurogenic bladder masquerading as posterior urethral valve: a case report

Background

Pseudotail with occult spinal dysraphism with neurological deficit is a rare phenomenon. Ignoring pseudotail as sign of occult spinal dysraphism may lead to catastrophe in diagnosis and further management.

Case presentation

We are reporting a case of a 30-month-old male child who presented with a tail-like structure at lower back and dribbling of urine since birth. On initial evaluation at some other hospital, he was misdiagnosed as posterior urethral valve and underwent fulguration of valve. However, dribbling of urine persisted after initial procedure. On evaluation at our center, he was found to have pseudotail with occult spinal dysraphism and neurogenic bladder.

Conclusion

Pseudotail with occult spinal dysraphism with neurological deficit is a rare phenomenon. Neurogenic bladder in such case can be misdiagnosed as posterior urethral valve. So, neurogenic bladder with pseudotail should be evaluated cautiously to avoid misdiagnosis and mismanagement.

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.

Atlantoaxial limited dorsal myeloschisis: A report of two cases and review of literature

Introduction

Limited dorsal myeloschisis (LDM) is a rare form of spinal dysraphism that is characterised by a distinctive fibroneural stalk connecting the spinal cord to the overlying skin lesion. The skin lesions associated with LDM can appear benign clinically and careful evaluation with an MRI scan is essential for diagnosing LDM and to differentiate this entity from other forms of spinal dysraphism and benign causes of skin lesions.

Research question

There is a lack of reported atlantoaxial LDM in the literature. We sought to report the clinical presentation, radiological features and surgical management of the first two reported atlantoaxial LDM.

Material and methods

Clinical findings and radiological images of the two cases of atlantoaxial LDM that underwent surgical intervention at our institution were retrieved from the medical notes, operative records and imaging system.

Results

Both cases of atlantoaxial LDM (C0-1 and C1-2 respectively) underwent successful resection of the overlying cutaneous lesions and stalks to release the tethered spinal cords.

Discussion

The surgical management of LDM have been associated with good outcomes and consists of resecting the fibroneural stalk close to the underlying cord, releasing the tethered spinal cord and removing the overlying cutaneous lesion.

Conclusion

These are the first two reported cases of atlantoaxial LDM in the literature. We aim to raise awareness of this pathological entity and highlight the importance of establishing the correct diagnosis to guide definitive management, and report the favourable neurological outcome in these cases despite the rostral location.

•

Limited dorsal myeloschisis is a rare form of closed spinal dysraphism.

•

These are the first two reported cases of atlantoaxial limited dorsal myeloschisis.

•

Favourable surgical outcomes can be achieved despite the rostral location.

•

Dorsal midline cutaneous lesions should be investigated further with MRI scan.

•

The fibroneural stalk connects the overlying cutaneous lesion to the spinal cord.

Experience with human tail and its outcome

There are some common genetic heritages between human and mammals. Human tail, though rare is one of the most noticeable. Till the date, around 60 cases reported in the literature. A true human tail is a benign vestigial caudal cutaneous structure composed of adipose, connective tissue, muscle, vessels and nerves. A true human tail can be distinguished from a pseudotail as the latter is commonly associated with underlying spinal dysraphism, which requires specialised management. We report a case series of four caudal appendages. Two clients were infants, while others two were toddler and presented with cutaneous appendage arising from the lumbosacral region. Out of four, only one had associated spinal dysraphism and neurological manifestation while others did not have spinal dysraphism and neurological manifestation. The appendage was removed by the surgical excision. Clinicians should emphasise the use of 'true tail' and 'pseudo-tail' as the specific disparate terms as the clinical, radiological and histological findings of these conditions differs significantly, along with the management strategies and outcomes.

Classification of the "human tail": Correlation between position, associated anomalies, and causes

INTRODUCTION

Numerous case reports have indicated that the "human tail" is not always a harmless protrusion but can be associated with anomalies such as occult dysraphic malformations. However, the definition and classification of this anomaly have not been discussed. A prevailing hypothesis is that the "human tail" is a residual embryonic tail. Herein, we attempted to classify and define the human tail and investigate the frequency of this anomaly.

MATERIALS AND METHODS

We first defined the human tail as a protrusion on the dorsal side of the lumbar, sacrococcygeal, and para-anal regions identified after birth. We collected case reports written in English, Japanese, French, German, and Italian that were published from the 1880s to the present.

RESULTS

We discovered two important findings: (a) the cause of this anomaly may differ even though the "tails" resemble each other closely in appearance and (b) its position tends to be correlated with the type of anomaly and its associated cause. We propose a new classification of the human tail based on these findings.

CONCLUSION

Our classification may facilitate more accurate treatment and precise case descriptions of the human tail.

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-like cutaneous appendage with a contiguous stalk of limited dorsal myeloschisis

PURPOSE

Limited dorsal myeloschisis (LDM) is characterized by a fibroneural stalk linking the skin lesion to the underlying spinal cord. On account of the external skin lesion, all LDMs are either flat (nonsaccular) or saccular, and a human tail-like cutaneous appendage has not been reported.

METHODS

In our 14 LDM patients, 2 had tail-like appendages. We retrospectively analyzed the relationship between the appendage and the LDM tract from the clinicopathological findings of these 2 patients.

RESULTS

Preoperative magnetic resonance imaging including three-dimensional heavily T2-weighted images demonstrated an intradural tethering tract, but failed to reveal the precise communication with the appendage. However, surgery revealed the extradural and intradural slender stalk, starting at the base of appendage and running through the myofascial defect. Histological examination demonstrated that there was a tight anatomical relationship between the fibroadipose tissue of the appendage and the fibrocollagenous LDM stalk.

CONCLUSION

When there is potential for an LDM stalk in patients with an appendage, a meticulous exploration of the stalk leading from an appendage is required. Clinicians should be aware of possible morphological variations of skin lesions associated with LDM.

A Rare Case of "Human Tail" Associated with Lipomyelomeningocele and Tethered Cord

Human tail might be the most interesting cutaneous sign of neural tube defects. From little cutaneous appendixes to 20-cm-long taillike lesions were reported in the literature. They may occur connected to an underlying pathology such as lipoma or teratoma, but most of the time, they conceal an underlying spinal dysraphism. Many classifications about human tails have been suggested in history, but the main approach to these lesions is, independent of the classification, always the same: investigating the possible spinal dysraphism with concomitant pathologies and planning the treatment on the patient basis.

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.

A tale of two "tails:" A curiosity revisited

A human tail or a caudal appendage is a rare condition with preconceived notions and stigmata. They could be either true tails or “pseudotails” based on their embryology. Clinically, they are considered as a marker of occult spinal dysraphism. We report two such cases with tethering of cord, one of which was associated with a lipomeningomyelocele. These patients are in need of meticulous evaluation and appropriate management.

A bony human tail causing tethered cord syndrome: case report

INTRODUCTION

Dorsal cutaneous appendages, sometimes referred to as "human tails," are considered to be markers of underlying occult spinal dysraphism. Rarely, these tail-like structures can themselves be the cause of tethered cord syndrome. However, to date, a "bony human tail" causing tethered cord has not been reported in the literature. One such rare lesion is being reported.

DISCUSSION

A 2-days-old female child was brought for neurosurgical consultation with a skin-covered bony protuberance in the lower back. Examination of the child did not reveal any neurological deficits. Plain radiographic and CT evaluation showed a dorsal bony protuberance arising from the posterior elements of L1 vertebra. MRI showed the cord to be displaced posteriorly and adherent to the undersurface of the bony tail through a lipoma. During surgery, the bony "tail" was excised, and the cord was untethered with excision of the lipoma, which was tethering the cord to the bony "tail." When examined 1 year later, the child was developing normally without any focal neurological deficits.

CONCLUSIONS

This case is being reported for its rarity and to highlight the hitherto unreported occurrence of "bony human tail" causing tethered cord syndrome.

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.

Unusual Spinal Dysraphic Lesions

Human tail and multiple spinal dysraphism are unusual congenital malformations. Human tail appeared as a prominent lesion from the lumbosacrococcygeal region, generally without connection between the tail and the neurospinal axis. Spinal dysraphisms are usually isolated, reaching 0.038% of incidence of multiple spinal dysraphisms in the same child. There were three cases described of unusual spinal dysraphic lesions: two cases of human tail and a case of a multiple thoracic myelomeningocele. The literature about diagnosis and treatment was reviewed. Microsurgical technique was performed to provide better exploration of the lesions, and resection could be done in those congenital malformations, without morbidity.

Surgical treatment of a patient with human tail and multiple abnormalities of the spinal cord and column

The dorsal cutaneous appendage, or so-called human tail, is often considered to be a cutaneous marker of underlying occult dysraphism. The authors present a case of human tail occurring in a 9-month-old infant with multiple abnormalities of the spinal cord and spine. Examination revealed unremarkable except for a caudal appendage and a dark pigmentation area in the low back. Neuroradiological scans revealed cleft vertebrae and bifid ribbon, split cord malformations, block vertebrae, and hemivertebra. Surgical excision of the tail and untethering the spinal cord by removal of the septum were performed. The infant had an uneventful postoperative period and was unchanged neurologically for 18 months of followup. To our knowledge, no similar case reports exist in the literature. The specific features in a rare case with a human tail treated surgically are discussed in light of the available literature.

Imperforate anus with a rectovestibular fistula and pseudotail: a case report

INTRODUCTION

Human tails and pseudotails are rare sacrococcygeal lesions that are associated with a wide variety of anomalies and syndromes. Anorectal malformations are also relatively uncommon congenital defects that often occur in conjunction with syndromes or other congenital abnormalities. The anomalies associated with both disorders determine the timing and approach to surgical correction. We present an unusual case of a patient with both imperforate anus and a pseudotail in the absence of a syndrome or other associated anomalies and we emphasize the necessity of a thorough preoperative evaluation.

CASE PRESENTATION

A Caucasian girl was born at term after an uncomplicated pregnancy and was noted at birth to have a skin-covered posterior midline mass and imperforate anus with a fistula to the vaginal vestibule. Ultrasound and magnetic resonance imaging revealed a predominately fatty lesion without presacral extension and ruled out associated spinal and cord abnormalities. The patient underwent diversion with colostomy and a mucous fistula in the newborn period as a fistulogram demonstrated a long fistulous tract to normal rectum and it was anticipated that anoplasty and resection of the mass would require extensive posterior dissection. The sacrococcygeal mass was removed during posterior sagittal anorectoplasty at the age of six weeks which was determined to be a pseudotail because of the composition of brown fat and cartilage. The patient is now 14 months old with normal bowel function after a colostomy takedown.

CONCLUSION

A comprehensive preoperative assessment and thoughtful operative plan were necessary in this unusual case because of the extensive differential diagnosis for sacrococcygeal masses in the newborn and the frequency of anomalies and syndromes associated with tail variants and imperforate anus. The pediatricians and neonatologists who initially evaluate such patients and the surgeons who correct these disorders must be aware of the potential pitfalls in their management.

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.

Human tail and myelomeningocele

The human tail is rarely reported and is usually associated with underlying spina bifida occulta. A male newborn presenting a caudal appendage (human tail) with skin-covered myelomeningocele and tethered cord is described. Surgical excision of the human tail and repair of the myelomeningocele were performed 3 days after birth. After the operation, the patient had an uneventful convalescence and received follow-up at our outpatient clinic without any neurological sequelae. To our knowledge, no similar case report exists in the literature. Like other skin-related lesions in the lumbosacral area, the present case of caudal appendage with myelomeningocele is only a cutaneous sign of underlying spinal dysraphism since the skin and nerve system are related by their similar ectodermal origin. After excision of the tail and repair of an underlying lesion, long-term follow-up of the neurological status is warranted.