46 - Spinal tract Pathways

45 - Lymph nodes of Neck

*The lymph nodes of the neck can be divided into six levels within the defined anatomic triangles. These groups and the areas that they drain are particularly important when locating and working up a "neck mass" or possible malignancy. The groups and drainage areas are as follows:

I--Submental and submandibular nodes
II--Upper jugulodigastric group
III--Middle jugular nodes (draining the nasopharynx and oropharynx, oral cavity, hypopharynx, larynx.
IV--Inferior jugular nodes draining the hypopharynx, subglottic larynx, thyroid, and esophagus.
V-- Posterior triangle group
VI--Anterior compartment group
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*Here are a few questions related to the neck lymph nodes, try answering them :

1q: Lymph nodes metastases from oropharyngeal cancers most commonly occur at ?
a. Level I
b. Level II
c. Level III
d. Level IV
e. Level V

answer b. Level II.(subdigastric nodes)

2q:  Which of the following are the level III lymph nodes of the neck ?
a. Upper jugular chain nodes
b. Middle jugular chain nodes
c. Lower jugular chain nodes
d. Posterior triangle nodes
e. Submental nodes

answer b. Middle jugular chain nodes.

3q: A lymph node that is inferior to the cricoid, superior to the clavicle and deep to the sternocleidomastoid muscle (SCM) in what level ?
a. Level I
b. Level II
c. Level III
d. Level IV

answer d. Level IV.


*These questions have been taken from Page 126 of the Schwartz's principles of surgery (8th ed) - self-assesment and review .

44 - Coronary sinus

*The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the myocardium of the heart.
*It is present in humans and other animals.
*The coronary sinus opens into the auricle, between the inferior vena cava and the auriculo-ventricular opening.
*It returns the blood from the substance of the heart, and is protected by a semicircular fold of the lining membrane of the auricle, the coronary valve. ( valve of Thebesius).
*The sinus, before entering the auricle, is considerably dilated - nearly to the size of the end of the little finger.
*Its wall is partly muscular, and at its junction with the great coronary vein is somewhat constricted and furnished with a valve consisting of two unequal segments.

*It is located in the right atrium and runs transversely in the groove between the left atrium and ventricle on the posterior surface of the heart.
*The coronary sinus orifice (opening) is just superior to the septal leaflet of the tricuspid valve.
*The coronary sinus orifice is also known as the ostium of the coronary sinus, and is guarded by the Thebesian valve.

*It receives blood mainly from the small, middle, great and oblique cardiac veins.
*It also receives blood from the left marginal vein and the left posterior ventricular vein.
*The anterior cardiac veins drain directly into the right atrium. (Some small veins drain into any of the four chambers of the heart.)
*It drains into the right atrium on the posterior, inferior surface, medial to the inferior vena cava opening.

43 - Adductor canal (Subsartorial/Hunter's canal)

*The adductor canal (Subsartorial/Hunter’s canal) is an aponeurotic tunnel in the middle third of the thigh, extending from the apex of the femoral triangle to the opening in the Adductor magnus, the Adductor hiatus.

*It courses between the anterior compartment of thigh and the medial compartment of thigh, and has the following boundaries:

1. anterolaterally - the Vastus medialis.
2. posterior - the Adductor longus. It is covered in by a strong aponeurosis which extends from the Vastus medialis, across the femoral vessels to the Adductor longus and magnus.

Lying on the aponeurosis is the Sartorius muscle.

*The canal contains the femoral artery, femoral vein, and branches of the femoral nerve (specifically, the saphenous nerve, and the nerve to the Vastus medialis).

*Named after JOHN HUNTER.