In this issue :
Dr. Patnaik V.V.Gopichand
Gross Anatomy of the Caudate Lobe of the Liver
Sahni, D., Jit, I., Sodhi L.
Department of Anatomy, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Branching Pattern of Axillary Artery - A Morphological Study
*Patnaik V.V.G., Kalsey, G; Singla Rajan, K.
Department of Anatomy, Government Medical College, Amritsar, *Patiala. INDIA
The Course, Relations and The Branching Pattern Of The Middle Meningeal Artery In South Indians
Manjunath, K.Y. & Thomas, I.M.
Department of Anatomy, St. John�fs Medical College, Bangalore-560 034 INDIA
Morphometry of the Human Inferior Olivary Nucleus
Dhall, U; Chhabra, S. & Rathi, S.K.
Department of Anatomy, Pt. B.D. Sharma P.G.I.M.S., Rohtak. INDIA
Management of Turner Syndrome in India Using Anthropometric Assessment of Response to Hormone Replacement Therapy.
Sehgal R. and Singh A.
Department of Anatomy, Maulana Azad Medical College and Associated Lok Nayak, G.B. Pant & G.N.E.C. Hospitals, New Delhi ? 110 002 INDIA.
Insertion Of Umbilical Cord On The Placenta In Hypertensive Mother
Rath* G, Garg** K, and Sood*** M.
*Department of Anatomy, ***Department of Obstetrics & Gynaecology, Lady Hardinge Medical College, New Delhi-110001
**Department of Anatomy, Santosh Medical College, Gaziabad. INDIA
Utility Of Finger Prints in Myocardial Infarction Patients
Dhall, U; Rathee, S.K; *Dhall, A;
Department of Anatomy & *Medicine, Pt. B.D. Sharma, PGIMS, Rohtak. INDIA
The Prenatal Parotid Gland
Fouzia Nayeem, Sagaff S., *Krishna G., **Rao S.
Department of Anatomy, K.A.A.U. Jeddah. Department of *Pediatrics & **Surgery, Osmania Medical College, Hyderabad. INDIA
Possibility of Cell Death Induced Skeletal Malformations Of The Upper Limb
Department of Anatomy, B.R.D. Medical College, Gorakhpur?273013 INDIA,
Efficacy of Manual Bladder Expression in Relieving Urine Retention After Traumatic Paraplegia In Experimental Animals.
Preeths, T.S., Sankar, V. Muthusamy, R.
Department of Anatomy, Dr. A. Lakshmanasamy Mudaliar Postgraduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai 600 113, India.
Stress And Serum Cholesterol Levels-An Experimental Study
Jain, S.K. *Pandey, S.N. *Srivastava, R.K. Ghosh, S.K.
Department of Anatomy, D.R.P.G. Medical College, Kangra at Tanda. * Department of Anatomy, G.S.V. Medical College, Kanpur.
Effect of Ibuprofen On White Cell Series of Bone Marrow Of Albino Rats
* Bhargava, R., Chandra, N., Naresh, M., *Sakhuja S.
* Department of Anatomy, M.L.N. Medical College, Allahabad * Lady Hardinge Medical College, N. Delhi, India.
JB4 An Embedding Medium For Flourescent Tracer Technique
*Gupta, M; **Mishra, S., ***Sengupta P.
Department of Anatomy, *PGI, Chandigarh; **AIIMS, N. Delhi; ***UCMS, New Delhi. INDIA
Comparative Anatomy of Cardiac Veins in Mammals
Department of Anatomy, Institute of Medical Sciences B.H.U., Varanasi?5. INDIA
Aplasia Cutis Type 9 With Trisomy-13 Syndrome ? A Rare Association
Adhisivam, B, Narayanan, P, Vishnu Bhat, B, *Ramachandra Rao. R*, *Rao. S*, Kusre, G.*
Department Pediatrics & *Anatomy, JIPMER, Pondicherry - 605 006
Absence of Musculocutaneous Nerve And The Innervation of Coracobrachialis, Biceps Brachii And Brachialis From The Median Nerve
Sud, M.; Sharma A.
Department of Anatomy, Christian Medical College, Ludhiana. Punjab INDIA.
A Rare Pseudo Ansa Cervicalis: A Case Report
Indrasingh I. and Vettivel S.
Department of Anatomy, Christian Medical College, Vellore, India
A Rare Variation In The Relation Of Omohyoid Muscle: A Case Report
Vettivel, S. Korula, A. and Koshy S.
Department of Anatomy, Christian Medical College, Vellore, India
Surgical Incisions ? Their Anatomical Basis Part II - Upper Limb
1Patnaik V.V.G., 2Singla Rajan. K., 3 Gupta P.N.
Department of Anatomy, Government Medical College, Patiala1, Amritsar2, 3Department of Orthopedics, Government Medical College, Chandigarh. INDIA
Anatomy Of Temporomandibular Joint?A Review
1Patnaik V.V.G., 3Bala Sanju; 2Singla Rajan K. Department of Anatomy, Govt. Medical College, 1Patiala, 2Amritsar, 3Department of Oral & Maxillofacial Surgery, Pb. Govt. Dental College, Amritsar
J Anat. Soc. India 49(2) 178-179 (2000)|
A Rare Pseudo Ansa Cervicalis: A Case Report
Indrasingh I. and Vettivel S. Department of Anatomy, Christian Medical College, Vellore, India
Abstract : Superior root of ansa cervicalis is the descending branch that leaves the hypoglossal nerve and inferior root forms from the second and third cervical nerves. The two roots anastomose to form a typical ansa cervicalis. In the present case, on the left side of the neck, a typical ansa was absent and a pseudo ansa cervicalis was formed by a root from the superior cervical sympathetic ganglion and another root from the vagus. Muscular branches to infrahyoid muscles did not arise from the ansa.
Keywords : Ansa cervicalis, pseudo, superior cervical sympathetic ganglion, vagus
Ansa cervicalis is a loop of nerves in the neck formed by the junction of two main nerve roots derived from ventral rami of cervical nerves. The superior root (descendens hypoglossi) branches off from the hypoglossal nerve. The inferior root is from the second and third cervical nerves. The two roots form a loop known as the ansa cervicalis (ansa hypoglossi) at the point (summit) of their anastomosis. Normally, the descending branch that leaves the hypoglossal nerve (descendens hypoglossi) descends in the anterior wall of the carotid sheath. It contains only fibres from the first cervical nerve. After it gives a branch to the superior belly of the omohyoid, it is joined by the ansa�fs inferior root. Branches from the ansa supply the remaining infrahyoid (strap) muscles, namely, steronohyoid, sternothyroid, and inferior belly of omohyoid. Another branch descends into the thorax to join the cardiac and phrenic nerves (Gray�f 1876; Turner, 1893; Larsel, 1953; Berry et al. 1995). The ansa cervicalis nerve formation is relatively complex, as its course and location along the great vessels of the neck vary. A rare variation of the ansa cervicalis is reported.
Material and Method :
In a routine dissection of an adult male cadaver in the Department of Anatomy, a rare atypical ansa cervicalis was found on the left side. The roots of the ansa were dissected to their origin. The specimen was photographed.
An atypical pseudo ansa cervicalis was present. The inferior root arose from the vagus and the superior root branched from the superior cervical sympathetic ganglion (Fig. 1). Both the roots anastomosed posteromedial to the carotid sheath to form a pseudo ansa cervicalis. Two branches from the ansa descended into the thorax but one joined the vagus. The ansa did not give muscular branches to the infrahyoid muscles. Muscular branches to geniohyoid and thyrohyoid were from the hypoglossal nerve. The branch to thyrohyoid continued and supplied the sternothyroid. The nerve to sternohyoid arose directly from the loop between first and second cervical nerves.
Near the base of the skull, the first cervical nerve communicated with sympathetic trunk, vagus, and hypoglossal nerve.
After a short course, the first cervical ventral ramus (Berry et al. 1995; Chhetri and Berke, 1997) descends anterior to the transverse process of atlas and joins the ascending branch of the second cervical ventral ramus. From that loop, communicating branches pass to the hypoglossal nerve, vagus and sympathetic trunk. The hypoglossal branch later leaves it as a series of branches viz. meningeal, superior root of the ansa cervicalis, nerves to thyrohyoid and geniohyoid.
The hypoglossal nerve (Berry et al. 1995; Chhetri and Berke, 1997) communicates with the sympathetic trunk, and first and second cervical nerves. Close to its exit from the base of skull, near the atlas, the hypoglossal nerve is joined by branches from the superior cervical ganglion and a filament from the loop between the first and second cervical nerve, which leaves the hypoglossal as the superior root of the ansa cervicalis, the nerve to thyrohyoid, and the nerve to geniohyoid. The upper portion of the sternohyoid and sternothyroid are possiblly innervated by branches from superior root (Hollinshead 1968), branches derived from the hypoglossal nerve, or from a network of nerve filaments overlying oblique line of the thyroid cartilage (Yerzingatsian, 1944). Hypoglossal nerve lies against the posterior surface of the vagus, and superior cervical ganglion, where it exchanges branches of communication with the vagus and sympathetic trunk. It makes a half-spiral turn round the inferior ganglion of vagus, being united with it by connective tissue. The vagal connections occur close to te skull, numerous filaments passing between the hypoglossal nerve and the inferior vagal ganglion in the connective tissue uniting them (Chhetri and Berke, 1997). Classically, twigs from the ansa are occasionally reported to descend into the thorax and join the cardiac and phrenic nerves (Gray, 1876; Larsell, 1953; Berry et al. 1995). Rarely, a nerve filament from the superior root passes into the thorax, where it joins the sympathetic trunk or vagus; in these cases, the aberrant branch is itself probably derived originally from either sympathetic or vagus (Piersol, 1911). Turner (1893) reported a case of the phrenic nerve receiving a root of origin from the superior root; C3 fibres of phrenic nerve run in inferior root and part of superior root before given off to join phrenic nerve within thorax. Ansa was found to participate in the innervation of heart, to communicate with the trunk of the vagus and phrenic nerve and to participate in the innervation of the pericardium (Paviraev and Chernikov, 1967). Accessory phrenic nerve frequently arises from ansa cervicalis.
Fig. 1. Pseudo ansa cervicalis formed by a root from superior cervical ganglion and a root from vagus.
S - superior cervical ganglion
V - vagus
Arrow pointing the ansa (A)
The ansa cervicalis is utilized to reinnervate the paralyzed larynx (Crumley and Izdebski, 1986). The anatomic course and morphology of the ansa cervicalis are complicated by the variable course and location along the great vessels, as well as the significant differences observed in the arrangement of its contributing roots and regional branching patterns (Chhetri and Berke, 1997). Occasionally, the superior root seems to be derived from the vagus but in these instances the fibres can be traced back to their true origin from the cervical plexus (Piersol, 1911). A case of superior root arising from vagus was reported from this department (Indrasingh et al. 1999).
In the present case (Fig. 1), superior root of the ansa arises from the superior cervical sympathetic ganglion instead of from the hypoglossal nerve but muscular branches to geniohyoid and thyrohyoid, sternothyroid, and superior belly of omohyoid arise from the hypoglossal nerve. Inferior root arises from the vagus instead of from the 2nd and third cervical nerves. One branch from the pseudo ansa cervicalis rejoined the vagus but two branches communicated and entered the thorax. These may be explained as the fibres of the grey rami communicantes of the first four cervical nerves joining the superior cervical sympathetic ganglion, leaving the ganglion as superior root of the ansa to join cardiac nerve and other autonomic sensory fibres as well as autonomic motor fibres from or to thorax passing through the pseudo ansa cervicalis and its branches (cardiac, phrenic, and any other visceral nerves).
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