|LETTER TO THE EDITOR
|Year : 2016 | Volume
| Issue : 1 | Page : 60-61
Anomalous anterior and posterior nerve root openings
Pavan Kumar Pelluru, Aniruddh Kumar Purohit
Department of Neurosurgery, Nizam's Institute of Medical Sciences, Hyderabad, Telangana, India
|Date of Web Publication||10-Aug-2016|
Aniruddh Kumar Purohit
Department of Neurosurgery, Nizam's Institute of Medical Sciences, Hyderabad, Telangana
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Pelluru PK, Purohit AK. Anomalous anterior and posterior nerve root openings. Indian J Cereb Palsy 2016;2:60-1
Normally, both anterior and posterior spinal nerve roots run together in cauda equina and pass through a single opening in the thecal sac with its dural-arachnoid sleeve. They pass further remaining together through the corresponding intervertebral foramen [Figure 1]a and b. ,,, As an anomaly, two separate openings anterior and posterior nerve root in the thecal sac has not been published in English literature to the best of our knowledge.
|Figure 1: Normal intradural course of anterior and posterior nerve roots at the cord (a) and cauda equina level (b)|
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Here, we present a child with cerebral palsy who underwent selective posterior rhizotomy (SPR) which involves partial sectioning of the posterior nerve rootlets for reducing the hyperactive, myotatic, monosynaptic spinal reflex pathway so as to reduce spasticity. Interestingly, while identifying anterior and posterior nerve roots at the site of thecal openings, we found bilaterally the anterior and posterior nerve roots of both L5 and S1 were passing through separate openings in the thecal sac [Figure 2]. We could differentiate them on mechanical stimulation. The anterior roots alone showed muscle contractions. There were fibrous bands also on the right side between and around the anterior and posterior roots at S1 level.
|Figure 2: Anterior and posterior nerve roots of S1 are seen passing through separate thecal openings and having fibrous bands. Operative microscope picture taken during selective posterior rhizotomy. (S=Sensory. M= Motor)|
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Many different types of the root abnormalities have been described in literature. However, we found this new anomaly that has not been classified and reported so far. Operating surgeon should be aware of such an anomalous course of the nerve roots to correctly identify the root number (say S1 or L5) so as to avoid wrong level sectioning and also to avoid sectioning of anterior roots while performing SPR.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
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[Figure 1], [Figure 2]