Easy Medical Journey

  Blood Supply Of Heart The heart is supplied by two coronary arteries, right and left, which arise from the ascending aorta. RIGHT CORONARY ARTERY It is smaller than the left coronary artery. It arises from the anterior aortic sinus of ascending aorta and descends in the right anterior part of the coronary sulcus up to the junction of right and inferior margins of the heart.  Here, it gives a marginal branch to the lower margin of the sternocostal surface. Then it curves around the lower margin of the heart to reach the diaphragmatic surface where it continues in the right posterior part of the coronary sulcus.  After crossing the crux of the heart, it terminates by anastomosing with the circumflex branch of the left coronary artery. BRANCHES These are: • Larger branches ~Marginal artery ~ Posterior interventricular artery • Smaller branches     ~SA nodal artery in 60% cases     ~Right conus artery     ~Unnamed branches to the right atrium a...

  RADIAL NERVE The radial nerve is the thickest and largest nerve of the upper limb. ROOT VALUE Ventral rami of C5, C6, C7, C8 and T1 ORIGIN COURSE & RELATIONS The course and branches of the radial nerve, which passes through three regions of the arm: axilla, radial groove on the back of the arm, and front of the forearm. Axilla: In axilla the radial nerve lies against the muscles forming the posterior wall of the axilla, and it gives two muscular branches to supply the long and medial heads of triceps and one cutaneous branch. Radial Groove :  In the radial groove it gives three muscular branches to supply the long and medial heads of triceps and anconeus and two cutaneous branches. Arm:  On the front of the arm, the radial nerve lies between brachialis on the medial side and brachioradialis and extensor carpi radialis longus on the lateral side. Forearm:  In the forearm, the radial nerve divides into two terminal branches: the deep terminal branch (posteri...

  ULNAR NERVE The ulnar nerve is so named because it runs along the ulnar side of the upper limb.   ROOT VALUE Ventral rami of C8 and T1. It also gets contribution from ventral ramus of C7. COURSE & RELATIONS It is the continuation of the medial cord of brachial plexus in the axilla. It courses successively through four regions: axilla, arm, forearm and hand, where it terminates by dividing into superficial and deep branches. The course and relations of ulnar nerve in these regions are as follows. Axilla: In axilla, the ulnar nerve lies between the axillary vein and the axillary artery on a deeper plane medial to 3rd part of axillary artery. Arm:   It enters the arm by running downwards on the medial side of the brachial artery in its proximal part. At the midarm (i.e. at the level of insertion of coracobrachialis), it pierces the medial intermuscular septum to enter the back of arm. Here it descends to run in a groove on the back of medial epicondyle of humerus,...

  SHOULDER JOINT CLASSIFICATION Synovial joint of ball and socket type. ARTICULAR SURFACES They are formed by the large hemispherical head of humerus and shallow glenoid cavity of scapula. The glenoid articular surface is deepened by the glenoid labrum . Glenoid labrum • It is a rim of fibrocartilage attached to the peripheral margin of the glenoid cavity. • It is triangular in cross-section and deepens the shallow glenoid cavity. LIGAMENTS Capsular Ligament • Attachments  Medially - To peripheral margin of glenoid cavity outside the glenoid labrum. The supraglenoid tubercle is intracapsular. Laterally - To anatomical neck of humerus except on medial side where it descends about 2-3 cm on the shaft, up to the surgical neck of humerus . • Muscles strengthening the capsule  In general, the capsule is loose and lax, but it is strengthened by the musculotendinous (rotator) cuff formed by the following muscles   Supraspinatus- above  Subscapularis- in front Infraspi...

BRACHIAL PLEXUS FORMATION :  It is formed by ventral primary rami of C5, C6, C7, C8 and T1 . COMPONENTS : The brachial plexus consists of four components : • Roots • Trunks • Divisions • Cords LOCATION : • Roots and trunks lie in the root of neck. • Divisions lie behind the clavicle. • Cords lie in the axilla. BRANCHES : From Roots • Dorsal scapular nerve (C5) for rhomboids. • Nerve to serratus anterior (C5, C6 and C7) for serratus anterior as the name implies. From Trunk (Only Upper Trunk Gives Branches) • Suprascapular nerve (C5 and C6) for supraspinatus and infraspinatus muscles. • Nerve to subclavius. From Cords • Lateral cord Lateral pectoral nerve (C5-C7) Lateral root of median nerve (C5-C7) Musculocutaneous nerve (C5-C7) Mnemonic: Laila Loved Majnu. • Medial cord Medial pectoral nerve for pectoralis major and pectoralis minor Medial cutaneous nerve of arm Medial cutaneous nerve of forearm Medial root of median nerve Ulnar nerve Mnemonic: M4U • Posterior cord Upper subscapula...