Type of Article:  Original Research

Volume 5; Issue 1 (March 2017)

Page No.: 3622-3624

DOI: https://dx.doi.org/10.16965/ijar.2017.123


Naveena  Swargam *1,  Shabana  Sultana 2.

*1 Associate Professor,  Department  of  Anatomy,  ESIC  Medical College,  Sanathnagar, Hyderabad,  Telangana  State,  India.

2  Tutor,  Department  of  Anatomy,  Apollo  Institute  of  Medical  Sciences  and  Research,  Hyderabad,  Telangana  State,  India.

*Corresponding Author:       Dr. Naveena Swargam, Associate Professor,  Department  of  Anatomy,  ESIC  Medical College,  Sanathnagar, Hyderabad,  Telangana  State,  India.  Ph. No.   09885124371 E-Mail:  naveena.swargam@yahoo.com


Introduction: Sciatic nerve is the largest nerve in  the  body.  It  originates  from  the  sacral  plexus  from  L4-S3  roots  in  the  form  of  two  nerve  trunks.  The  Tibial  nerve  and  Common peroneal  nerve  are  encompassed  by  single  epineural  sheath  and  eventually  separates.  Variations  in  the  level  of  bifurcation  of  the  sciatic  nerve  are  common  and  being  reported  by  several  authors.  The  bifurcation  into  its  two  major  trunks  may  occur  anywhere  between  the  sacral  plexus  and  popliteal  space.  Significant  number  of  variations  in  the  bifurcation,  course,  relation  and  distribution  of  its  branches  were  encountered  in  sciatic nerve.  These  variations  may  cause  nerve  compressions  under  other  anatomic  structures,  resulting  in  sciatica.

Materials and Methods: 30  lower  limbs  were  dissected  in  a  period  of  3  years  during  the  routine  dissection  to  note  the  relationship  between  piriformis  muscle  and  sciatic  nerve.  Only  in  2  lower  limbs  the  variation  in  division  of  sciatic  nerve was  observed  in  the  present  study.

Results: The  literature  was  reviewed  and  the  results  were  summarized  to  compare  the  incidence  with  the  previous  studies.  Incidence  of  this  variation  in  general  population  needs  to  be  investigated  so  as  to  create  awareness  among  surgeons  and  anaesthetists  about  the  degree  and  extent  of  variation  in  sciatic  nerve  formation.  Complete  sciatic  nerve  blockages  will  fail  even  after  multiple  punctures  and  attempts  if  the  sciatic  nerve  is  present  as  separately  sheathed  bundles  until  the  lower  gluteal  level.

Conclusion: The  aim  of  this  study  was  to  provide  and  define  the  level  of  the  sciatic  nerve  exit,  its  divisions  and  its  anatomical  variations  obtained  from  human  cadavers.  The  availability  of  assessment  of  level  of  bifurcation  of  sciatic  nerve  was  minimal  in  the  Indian  literature  so  this  study  was  taken  to  focus  a  fresh  light  on  the  frequency  of  the  level  of  bifurcation  of  sciatic  nerve.  The  differences  in  the  exit  of  two  divisions  of  sciatic  nerve  are  important  in  clarifying  the  clinical  etiology  and  treatment  of  pyriformis  syndrome.

Key  words:  Sacral  plexus,  Epineural  sheath,  Sciatica,  Pyriformis  syndrome..


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Cite this article: Naveena Swargam, Shabana Sultana. PATTERNS OF SCIATIC NERVE BIFURCATION AND THEIR CLINICAL RELEVANCE. Int J Anat Res 2017;5(1):3622-3624. DOI: 10.16965/ijar.2017.123