Unilateral anatomical variation of the ansa cervicalis.

The ansa cervicalis is a loop of nerves that is usually formed by the union of ventral rami of spinal nerves C1, C2, and C3. It is located in the carotid triangle of the neck, lying superficial to the carotid sheath. During routine dissection, unilateral variation of the ansa cervicalis was observed.

An unorthodox innervation of the gluteus maximus muscle and other associated variations: A case report.

Knowledge of peripheral nerve morphology, location, and variation is important for facilitating appropriate diagnosis and intervention. We present a unique case of absence of the inferior gluteal nerve and high division of the sciatic nerve. In this instance, the common peroneal nerve was found piercing the piriformis muscle and emerging distally in the form of two trunks: thin medial and thick lateral.