Unusual Path of Branches of Ilioinguinal Nerve: A Clinically Important Anatomic Variant

Ilioinguinal nerve is a collateral branch of lumbar plexus. Its anatomical variations in relation to adjacent musculoaponeurotic structures play a crucial role in the development of neuropathies associated with lower abdominal surgeries. In this report, we present a rare case of unusual course and branches of the ilioinguinal nerve, in a 55-year-old male cadaver. In the lateral part of inguinal canal ilioinguinal nerve gave three branches. Two of its branches pierced the external oblique aponeurosis, about 6 cm above the pubic symphysis, to supply the skin of the lower part of the anterior abdominal wall. Another branch pierced the conjoint tendon, in the medial part of the inguinal canal about 2 cm above the superficial inguinal ring. Knowledge of unusual path of these branches may be important to avoid injuries during the surgical repair of groin hernias. Further care should be taken while dealing with the conjoint tendon in the Bassini procedure.

A Rare Unilateral Variation in the Course of External and Internal Carotid Arteries

Vascular variations in the neck region are not uncommon. Knowledge of incidence of morphological variations in the course and branching of the carotid arteries is important for radiological interpretation and surgical correction when they are symptomatic. Internal carotid artery (ICA) is known to show elongation in its extra cranial course. Previous studies have demonstrated the incidence and clinical symptoms of this morphological entity. However, the occurrence of elongation and looping of the external carotid artery (ECA) is seldom reported in the literature. During regular dissections, we came across a rare case of unilateral morphological variation of both ECA and ICA, in a male cadaver aged about 55 years. ICA presented a curved course with convexity directed posteriorly, at the level of the C2-C3 vertebrae. ECA presented a pronounced kinking or coiling, one inch below the level of the angle of the mandible. In addition, a linguo-facial trunk arising from the ECA also presented a pronounced kinking throughout its entire length.

Variant Origin of the Left Vertebral Artery from a Vertebro-Subclavian Trunk Associated with an Unusual Branch Arising from the Brachiocephalic Trunk

Variant origin of the left vertebral artery (LVA) from the arch of aorta is well documented in the literature. Involvement of complex sequential developmental steps in the aortic arch formation results in different patterns of origin of LVA. Morphological variations in the LVA are thought to alter the cerebral hemodynamics and can cause the cerebral dysfunction. Knowledge of the morphological variations of the LVA is useful while performing the head and neck and thoracic surgeries. We here report one of the extremely rare patterns of the LVA origin, in a male cadaver aged about 65 years. LVA and left subclavian artery (LSA) arose as a common vertebro-subclavian trunk from the convexity of the aortic arch. Further, brachiocephalic trunk (BT) gave an unusual artery from its anterior surface. This artery divided into thymic and tracheal branches. Variant origin of thymic branch may be crucial during imaging and thymectomy procedures.

Sub-Brachialis Course of the Median Nerve in the Arm and its Possible Clinical Complications: A Case Report

The median nerve in its normal course in the arm crosses the brachial artery from lateral to medial side. It then passes superficial to the brachialis muscle and then enters the cubital fossa. During routine cadaveric dissection of the right upper limb, an unusual variation in the course of the median nerve was observed. The median nerve in the arm crossed the brachial artery from medial to lateral side and passed deep to the brachialis muscle. It then emerged from beneath the brachialis muscle and entered the cubital fossa. In the cubital fossa, it ran medial to the brachial artery as the normal course of the nerve. Further distribution of median nerve in the forearm and hand was observed to be normal. The anomaly reported here may result in the compression of the median nerve deep to the brachialis and hence resulting in mechanical disadvantages in the flexion at the wrist joint.