Antrochoanal polyps arise from the maxillary sinuses and are the much less common; ethmoidal polyps arise from the ethmoidal sinuses. Symptoms of polyps include nasal congestion, sinusitis, anosmia (loss of smell), and secondary infection leading to headache.
Relationship of internal jugular vein to the spinal accessory nerve (SAN). Spinal accessory nerve (SAN) posterior to the internal jugular vein. As the nerve approaches the sternocleidomastoid muscle (SCM), it may perforate the cleidomastoid portion of the SCM (80%) or run posterior to it (20%).
Obturator nerve. The obturator nerve begins at the medial border of the psoas major muscle. It travels through the obturator foramen (an opening in the pelvic bone) before entering the thigh, where it branches into two parts, an anterior branch and posterior branch.The obturator nerve is part of the group of nerves called the anterior lumbar plexus.t travels through the obturator foramen (an opening in the pelvic bone) before entering the thigh, where it branches into two parts, an anterior branch and posterior branch. The obturator nerve is part of the group of nerves called the anterior lumbar plexus.