Extradural Hemorrhage

Friday, January 12, 2018

An extradural, or epidural hemorrhage is a bleeding above the dura mater, which is the outermost of the three layers that make up the meninges in the head. It is caused by arterial damage, resulting from tearing of one of the branches of the middle meningeal artery. The epidural hemorrhage usually occurs in the region of the pterion. Arterial blood dam up between the periostial layer of the dura mater and the calvaria, making an expanding hematoma.

An extradural hemorrhage sometimes is caused by blow to the head that produces a minor loss of consciousness. After the injury, the patient usually regain consciousness and may stay aware for several hours. However, after this period of awareness, the patient falls into a state of drowsiness, and then into unconsciousness, leading to death.

Patellar Ligament

The patellar ligament is a band of fibrous connective tissue which connects the apex of the knee patella to the tibial tuberosity on top of tibia bone. It can be regarded as an extension of the quadriceps femoris tendon.

Spermatic veins

Thursday, January 11, 2018

The spermatic veins, also known as testicular veins, are the two blood vessels that drain the testicles. The right spermatic vein carries oxygen-depleted blood from the right testis directly into the inferior vena cava; while the left spermatic vein drains oxygen-poor blood from the left testicle into the left renal vein, making it hang lower than the right due to vascularity issues (blood remains for longer time in there than in the right.

Biceps brachii innervation

Wednesday, January 10, 2018

The arm biceps muscle is innervated by a branch of the musculocutaneous nerve, whose fibers arise from cervical vertebral roots C5, C6, and C7. The nerve supply to the biceps can be hindered or blocked by damage to this branch; this happens through entrapment between the biceps aponeurosis and brachialis fascia. It can also be injured through stretch.

Chronic leg ischemia

Tuesday, January 9, 2018

Chronic leg ischemia is a medical condition in which arteries in the leg have undergone atheromatous build-up, with luminal narrowing. This reduces the blood supply to the leg. The symptoms are leg pain, especially in the calf area, which is caused by occlusion or narrowing of the femoral artery, numbing sensation, etc.

Chronic leg ischemia is caused by smoking (tobacco), sedentary lifestyle, high triglyceride levels in bloodstream, etc.

Tonsillar artery

Wednesday, December 6, 2017

The tonsillar artery arises from the facial artery, which, in turn, comes off the external carotid artery. From its point of origin, it runs up between the styloglossus and pterygoideus muscles at the base of tongue, dividing into smaller-caliber blood vessels. The tonsillar branch of the facial artery supplies the tonsils and the root of the tongue.

Tongue innervation

Tuesday, December 5, 2017

The muscles of the tongue (styloglossus, genioglossus, hyoglossus, superior longitudinal and inferior longitudinal) are innervated by the hypoglossal nerve (CN XII), from which arise motor efferent nerve fibers that supply them all. The hypoglossal has only motor function and has its center in the hypoglossal nucleus in the medulla oblongata.

See deglutation reflex