IJAR.2017.123
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
PATTERNS OF SCIATIC NERVE BIFURCATION AND THEIR CLINICAL RELEVANCE
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
ABSTRACT
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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