Anatomy Flashcards
The middle meningeal artery is a branch of with artery?
Maxillary artery
What are the spleen’s embryonic origins?
Derived from the mesoderm of the dorsal mesentery. Although, it is unique because it gets its blood supply from a foregut derivative.
What nerve innervates the posterior portion of the external auditory canal?
The auricular branch of the Vagus nerve. Patients may experience vasovagal syncope after stimulation of this part of the auditory canal and may pass out (especially if inflamed).
What is the blood flow through the kidney?
Interlobar arteries → arcuate arteries → radial arteries → afferent arterioles → glomerular capillaries → efferent arterioles → peritubular capillaries → interlobar veins
An opening in what structure forms the superficial inguinal ring?
External oblique muscle aponeurosis
Where should a femoral nerve block be administered?
In the inguinal crease at the lateral border of the femoral artery.
Note that the femoral nerve is not part of the femoral sheath so the block should not be administered in the femoral ring.
What is the position of the ureters relative to the uterine arteries and veins?
Posterior to the arteries and veins. “Water under the bridge”=ureter carrying water, the uterine vessels signifying the bridge.
What does the iliohypogastric nerve innervate?
It arises from the L1 nerve root, emerges from the lateral border of hte upper psoas major, and passes behind the kidney anterior to the quadratus lumborum. It provides motor function to the anterolateral abdominal wall muscles. The anterior branch emerges above the superificial inguinal ring to innervate the skin above the pubic region and the lateral branch descends over the iliac crest to innervate the gluteal region. The anterior branch can be injured during an appendectomy, which causes decreased sensation at the suprapubic region.
What does the ilioinguinal nerve innervate?
It arises from the L1 nerve root and accompanies the spermatic cord through the superficial inguinal ring. It provides sensation to the upper and medial thigh and parts of the external genitalia.
What nerve courses togethers with the superior thyroid artery and vein?
The external branch of the superior laryngeal nerve (branch of the Vagus nerve). This nerve is a risk for injury during thyroid surgery. The cricothyroid muscle is the only muscle innervated by this nerve. This muscle tenses the vocal cords.
What is the function of the internal branch of the superior laryngeal nerve (branch of Vagus nerve)?
It provides sensory innervation to the laryngeal mucosa above the vocal cords. It does not innervate any muscles.
What is thoracic outlet syndrome (TOS)?
TOS is due to compression of the lower trunk of the brachial plexus in the scalene triangle, the space bordered by the anterior and middle scalene muscles and the first rib. Symptoms include upper extremity numbness, tingling, and weakness. It is due to an anomalous cervical rib, scalene muscular anomalies, or injury (e.g. repetitive overhead arm movements, trauma).
What does the musculocutaneous nerve innervate?
The major forearm flexors (e.g. biceps brachii, brachialis) and the coracobrachilais (flexes and adducts the arm). After innervating these muscles, the remaining fibers become the lateral cutaneous nerve of the forearm and provides sensory innervation of the skin of the lateral forearm. It is derived from the C5-C7 spinal nerve roots and arises from the lateral cord of the brachial plexus.
What part of the aorta does blunt aortic injury (i.e. traumatic aortic rupture due to sudden deceleration) usually damage?
The aortic isthmus, which is tethered in palce by the ligamentum arteriosum.
What 4 structures does the incision for a cricothyrotomy pass through?
- Skin
- Superficial cervical fascia (including SQ fat and platysma muscle)
- Investing and pretracheal layers of the deep cervical fascia.
- Cricothyroid membrane
