Welcome to International Journal of Anatomy and Research

Type of Article: Original Research

Year: 2016 | Volume 4 | Issue 3 | Page No. 2743-2749

Date of Publication: 31-08-2016

DOI: http://dx.doi.org/10.16965/ijar.2016.323

DIFFERENT LEVELS OF BIFURCATION OF SCIATIC NERVE: A NOVEL CLASSIFICATION BASED ON A CADAVERIC STUDY IN INDIAN POPULATION

Harsimran Grewal *¹, Rajan Kumar Singla ², Rupinder Singh ³, Mannat Singla ⁴.

^*1 Senior Resident, Department Of Anatomy, Government Medical College, Patiala,Punjab, India.

² Professor & Head Of Department, Department Of Anatomy, Government Medical College,Patiala, Punjab, India.

³ M.Sc. Student, Department Of Anatomy, Government Medical College, Patiala, Punjab India.

⁴ M.B.B.S Student, Department Of Anatomy, Government Medical College, Patiala, Punjab India.

Address: Dr. Harsimran Grewal, 16, The Mall, Opposite Polo Ground, Patiala-147001, Punjab, India.
E-Mail: grewalkim@gmail.com

ABSTRACT

Introduction: The Sciatic Nerve (SN) is the largest and thickest nerve in the body. It is composed of two nerves, the common peroneal (CPN) and the tibial (TN) which are bound together by a common sheath of connective tissue from their origin till the bifurcation at the superior angle of popliteal fossa. But this division may occur at any level above this point and rarely below it. These anatomical variations may contribute to clinical conditions such as piriformis syndrome, sciatica, coccygodynia and muscle atrophy.
Material and Methods: 30 Lower limbs of 15 cadavers (Male:Female -14:1) were dissected and examined to study the mode and level of bifurcation of SN.
Results: The highest incidence of SN bifurcation (63.3%) was observed at superior angle of popliteal fossa followed by division at junction of upper and middle 1/3rd of thigh in 20%, in the pelvis in 10% and in middle 1/3rd of thigh in 6.7%.
Conclusion: SN bifurcates terminally at different levels for which many classifications have been given. However  there are certain over lapping and thus confusions amongst them. Therefore, a new classification termed as Grewal et al classification has been designed and advocated for future studies. It may prove more helpful for anatomists to categorise different levels of bifurcation of SN and for surgeons, orthopaedicians and anaesthetists performing surgeries in the region and giving SN blocks at different levels.
KEY WORDS: Bifurcation Of Sciatic Nerve, Variations, Tibial Nerve, Common Peroneal Nerve, Piriformis Muscle.

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Harsimran Grewal, Rajan Kumar Singla, Rupinder Singh, Mannat Singla. DIFFERENT LEVELS OF BIFURCATION OF SCIATIC NERVE: A NOVEL CLASSIFICATION BASED ON A CADAVERIC STUDY IN INDIAN POPULATION. Int J Anat Res 2016;4(3):2742-2749. DOI: 10.16965/ijar.2016.323