Type of Article: Original Research
Year: 2016 | Volume 4 | Issue 3 | Page No. 2689-2691
Date of Publication: 31-08-2016
A STUDY ON THE VARIATIONS IN THE RELATIONSHIP BETWEEN THE RECURRENT LARYNGEAL NERVE AND THE VASCULAR PEDICLE OF THE THYROID GLAND
J.Thilagavathi * 1, V.Anandhi 2, Sudha Seshayyan 3.
*1 Associate Professor of Anatomy, Government Stanley Medical College, Chennai, Tamil Nadu, India.
2 Associate Professor of Anatomy, KAPV Government Medical College, Tiruchirappalli, Tamil Nadu. India.
3 Director of Anatomy, Madras Medical College, Chennai, Tamil Nadu, India.
Address: Dr.J.Thilagavathi, Associate Professor of Anatomy Government Stanley Medical College, Chennai, Tamil Nadu, India. Mobile: +919941239977
Background: A sound knowledge of normal human anatomy and common variations in it is very important for a surgeon operating on the neck because it is one of the most difficult areas to operate upon, there being very little space in this region. The recurrent laryngeal nerve (RLN) and inferior thyroid artery(ITA) are in close proximity to each other, and are greatly liable to be included in a ligature, crushed by an instrument or stretched during mobilization of the thyroid gland. Hence this study was carried out to observe the variations in the relationship of the recurrent laryngeal nerve to the vascular pedicle of the thyroid gland.
Materials and Methods: The recurrent laryngeal nerve was dissected in 20 embalmed cadavers from the department of Anatomy, Government Stanley Medical college and 15 post-mortem en-bloc specimens, from the Institute of Forensic medicine, Government Stanley medical college. The origin of 70 recurrent laryngeal nerves and their relation with inferior thyroid artery and its branches were dissected and noted. The results were tabulated and analyzed by tests for the significance of the difference in the proportions.
Results: On the right side, the recurrent laryngeal nerve was found in between the branches of the inferior thyroid artery in 51%, posterior to the inferior thyroid artery in 37% and anterior to the inferior thyroid artery in 11% of specimens. And on the left side, the recurrent laryngeal nerve was found 51.4% posterior to the inferior thyroid artery, 28.6% in between the branches of the inferior thyroid artery and 20% anterior to the Inferior thyroid artery. The Chi – Square test, showed statistically significant difference in the relationship of the recurrent laryngeal nerve to the Inferior thyroid artery in the right and left side. (P < 0.003)
Conclusion: The significant variations observed in the relationship of the recurrent laryngeal nerve to the Inferior thyroid artery on the right and left side would be important for surgeons who are doing thyroidectomy and any vascular surgery in the neck. A thorough knowledge of the laryngeal nerves and anatomical variations is necessary for safe thyroid surgery.
KEY WORDS: Recurrent laryngeal nerve, Vagus nerve, Inferior thyroid artery, Chi-square test.
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J.Thilagavathi, V.Anandhi, Sudha Seshayyan. A STUDY ON THE VARIATIONS IN THE RELATIONSHIP BETWEEN THE RECURRENT LARYNGEAL NERVE AND THE VASCULAR PEDICLE OF THE THYROID GLAND. Int J Anat Res 2016;4(3):2689-2691. DOI: 10.16965/ijar.2016.307