Posterior triangle of the neck which divides the space into two triangles: A) Nerves and plexuses: B) Vessels: C) Lymph nodes: D) Muscles: The accessory nerve (CN XI) is particularly vulnerable to damage during lymph node biopsy. Damage results in an inability to shrug the shoulders or raise the arm above the head, particularly due to compromised trapezius muscle innervation. The Internal jugular vein's superficial location within the posterior triangle also makes it vulnerable to injury. Posterior triangle of the neck The posterior triangle (or lateral cervical region) is a region of the neck. It has the following boundaries: Apex: Union of the sternocleidomastoid and
Hepatic veins ultimately from numerous central veins of the liver lobules. None of the hepatic veins have valves. The hepatic veins are divided into an upper and a lower group. The upper three drain the central veins from the right, middle, and left regions of the liver and are larger than the lower group of veins. The lower group of from six to twenty smaller hepatic veins come from the right lobe and the caudate lobe, are in contact with the hepatic tissue, and are valveless. All the veins empty into the inferior vena cava at the back of the liver. Budd–Chiari