<%server.execute "isdev.asp"%> An unusual case of split cord malformation with simultaneous ventral and dorsal bony spur at a single site: A Technical Challenge Agarwal A, Raheja A, Borkar SA, Mahapatra AK - J Pediatr Neurosci
home : about us : ahead of print : current issue : archives search instructions : subscriptionLogin 
Users online: 76      Small font sizeDefault font sizeIncrease font size Print this page Email this page


 
  Table of Contents    
CASE REPORT
Year : 2018  |  Volume : 13  |  Issue : 2  |  Page : 214-217
 

An unusual case of split cord malformation with simultaneous ventral and dorsal bony spur at a single site: A Technical Challenge


Department of Neurosurgery and Gamma Knife, All India Institute of Medical Sciences, New Delhi, India

Date of Web Publication5-Jul-2018

Correspondence Address:
Amol Raheja
Department of Neurosurgery and Gamma Knife, All India Institute of Medical Sciences, New Delhi 110029
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/JPN.JPN_99_17

Rights and Permissions

 

   Abstract 


Split cord malformation (SCM) with simultaneous ventral and dorsal bony spur at a single site is an extremely rare entity with only one other case reported so far. We present a second such case in a 13-month-old female child, who presented with a skin dimple over the lumbar region with overlying hairy patch without any associated lower limb weakness or urinary complaints. Imaging demonstrated a complex Type I SCM with simultaneous ventral and dorsal bony spur at L4-L5 level. Intraoperatively, the patient was confirmed to have a Type Ic SCM with a ventrally based bony spur going dorsally to attach on the hypertrophied posterior arch of L4 and a dorsal spur going ventrally to attach on the L4 vertebral body. After meticulous microsurgical excision of the spur, the child was stable and developed no fresh neurological deficits. We discuss the relevant surgical implications and possible embryological mechanisms involved in such a complex SCM.


Keywords: Dorsal spur, good outcome, split cord malformation, surgery, ventral spur


How to cite this article:
Agarwal A, Raheja A, Borkar SA, Mahapatra AK. An unusual case of split cord malformation with simultaneous ventral and dorsal bony spur at a single site: A Technical Challenge. J Pediatr Neurosci 2018;13:214-7

How to cite this URL:
Agarwal A, Raheja A, Borkar SA, Mahapatra AK. An unusual case of split cord malformation with simultaneous ventral and dorsal bony spur at a single site: A Technical Challenge. J Pediatr Neurosci [serial online] 2018 [cited 2022 Jan 27];13:214-7. Available from: https://www.pediatricneurosciences.com/text.asp?2018/13/2/214/235967





   Introduction Top


Split cord malformation (SCM) is a relatively uncommon condition, wherein the cord is divided into two variable segments with a fibrous or osteocartilaginous septum in between and surrounded by a single or two dural sheaths, respectively. It may present in an asymptomatic child with characteristic neurocutaneous markers or with neurologic, urologic, or orthopedic deficits. Although many cases of composite-type SCMs have been reported in literature,[1],[2] SCM with simultaneous ventral and dorsal bony spur at a single site is an extremely rare entity, with only one other case reported so far in the literature.[3] We present a second such case and discuss the relevant surgical implications and possible embryological mechanisms involved in such a complex SCM.


   Case Report Top


A 13-month-old female child presented to us with a skin dimple over the lumbar region with overlying hairy patch without any associated lower limb weakness or urinary complaints. Her physical examination revealed no other abnormalities. On imaging evaluation, magnetic resonance imaging showed a split cord from L2-L5 with broad-based spur at L4-L5 level with single thickened filum tethered at L5-S1 level with syrinx formation in the right hemicord from L1-L5 [Figure 1]. Noncontrast computed tomography showed deficient posterior elements of L5 to S1 with two bony spurs, one arising from the posterior aspect of L4 vertebral body and another from the hypertrophied L4 posterior arch [Figure 2].
Figure 1: Preoperative T2-weighted magnetic resonance images showing axial sections with (A) syrinx formation above the split (arrow), (B) Type Ic split cord malformation with syrinx in the larger right hemicord (arrow), (C) ventral (long arrow) and dorsal (short arrow) bony spurs with soft tissue in between, and sagittal section with (D) ventral (long arrow) and dorsal (short arrow) bony spurs with syrinx in the above cord

Click here to view
,
Figure 2: Preoperative computed tomography images in (A) axial, (B) sagittal, and (C) coronal sections showing ventral (long arrow) and dorsal (short arrow) bony spurs

Click here to view


The child was taken up for operative intervention, and intraoperatively, two bony spurs were confirmed with soft tissue in between—ventral spur based on the L4 vertebral body and a dorsal spur based on the L4 hypertrophied posterior arch. The cord was divided into two hemicords—right side larger than the left—which were reuniting below the spur to end in a single thickened fatty filum. There was a variable distance of split cords above the spurs suggestive of Type Ic SCM.[4] The spurs were excised with the help of a high-speed diamond drill, and the fatty filum was divided at S1 level. Dural bands and arachnoid adhesions tethering the cord were released [Figure 3]A. Dura was closed primarily and reinforced with muscle patch and tissue glue. Postoperative hospital stay of the child was uneventful with no new onset of neurological deficits and the postoperative computed-tomography scan demonstrated complete excision of the spurs [Figure 3]B.
Figure 3: (A) Intraoperative photograph after spur excision and detethering showing Type Ic split cord and (B) postoperative computed-tomography sagittal image showing complete excision of bony spurs

Click here to view



   Discussion Top


According to the classification system proposed by Mahapatra and Gupta,[4] Type I SCM is subdivided into four types with prognostic significance:[5] Type Ia, Type Ib, Type Ic, and Type Id, with the last one having the highest chance of developing postoperative neurological deficits.[5] The present case was a Type Ic SCM as per this classification. Complex SCM with both ventral and dorsal spurs at the same spinal level was diagnosed preoperatively, and accordingly, care was taken to surgically isolate the hypertrophied posterior arch to prevent any undue traction on straddling cord during laminotomy. Once both the spurs were partially drilled extradurally, dura was opened to expose the base of the ventral spur and the tip of the dorsal spur along the L4 vertebral body. Meticulous drilling of the bony spurs and the subsequent detethering of the cord led to a favorable neurological outcome.

According to the Unified Theory proposed by Pang et al. on the embryogenesis of SCM,[6] embryogenesis of SCM involves formation of an accessory neurenteric canal rostral to the primitive neurenteric canal. If the precursor cells within the endomesenchymal tract contain the meninx primitiva cells, they form a bony septum and Type I SCM, else a fibrous band giving rise to Type II SCM. Multiple accessory canals may give rise to composite-type SCMs with variable splits at different locations.[1] Generally, in cases of bony septum, a single bony spur usually arises from the posterior surface of the vertebral body, but there have been a few case reports of spurs arising from the posterior arch.[7],[8],[9] Chandra et al.[7] discussed two hypotheses for posterior origin of bony spur, including (1) disconnection of ventral cell mass after dorsal migration of meninx primitiva cells and (2) initial migration of meninx primitiva cells around the hemicords instead of between them to accumulate along the dorsal arch. It is quite unusual to have simultaneous ventral and dorsal bony spurs at the same spinal level. The reported child had soft tissue interposed between the two spurs, emphasizing that there is no single hypothesis that can explain such a unique observation. We believe that such cases are underreported in the literature and the true incidence of such complex SCMs is much higher than documented.


   Conclusion Top


Pathogenesis of SCM is still poorly understood and it is a complex multifactorial congenital malformation, which requires further detailed study to elucidate the underlying embryological and pathological mechanisms. It requires detailed imaging evaluation in the preoperative period and utmost intraoperative care so as to prevent new onset deficits in such rare patients.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

1.
Allawadhi P, Mahapatra AK. An unusual case of spinal dysraphism with four splits including three posterior spurs. Pediatr Neurosurg 2011;13:372-5.  Back to cited text no. 1
    
2.
Erşahin Y, Demirtaş E, Mutluer S, Tosun AR, Saydam S. Split cord malformations: Report of three unusual cases. Pediatr Neurosurg 1996;13:155-9.  Back to cited text no. 2
    
3.
Naik V, Mahapatra AK, Gupta C, Suri V. Complex split cord malformation with mediastinal extension of a teratoma and simultaneous ventral and dorsal bony spur splitting the cord. Pediatr Neurosurg 2010;13:368-72.  Back to cited text no. 3
    
4.
Mahapatra AK, Gupta DK. Split cord malformations: A clinical study of 254 patients and a proposal for a new clinical-imaging classification. J Neurosurg 2005;13:531-6.  Back to cited text no. 4
    
5.
Borkar SA, Mahapatra AK. Split cord malformations: A two years experience at AIIMS. Asian J Neurosurg 2012;13:56-60.  Back to cited text no. 5
    
6.
Pang D, Dias MS, Ahab-Barmada M. Split cord malformation: Part I: A unified theory of embryogenesis for double spinal cord malformations. Neurosurgery 1992;13:451-80.  Back to cited text no. 6
    
7.
Chandra PS, Kamal R, Mahapatra AK. An unusual case of dorsally situated bony spur in a lumbar split cord malformation. Pediatr Neurosurg 1999;13:49-52.  Back to cited text no. 7
    
8.
Prasad GL, Borkar SA, Satyarthee GD, Mahapatra AK. Split cord malformation with dorsally located bony spur: Report of four cases and review of literature. J Pediatr Neurosci 2012;13: 167-70.  Back to cited text no. 8
    
9.
Akay KM, Izci Y, Baysefer A. Dorsal bony septum: A split cord malformation variant. Pediatr Neurosurg 2002;13:225-8.  Back to cited text no. 9
    


    Figures

  [Figure 1], [Figure 2], [Figure 3]



 

Top
Print this article  Email this article
 
 
  Search
 
  
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Article in PDF (1,306 KB)
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  


    Abstract
   Introduction
   Case Report
   Discussion
   Conclusion
    References
    Article Figures

 Article Access Statistics
    Viewed1761    
    Printed60    
    Emailed0    
    PDF Downloaded56    
    Comments [Add]    

Recommend this journal