VESSELS & NERVES OF THE FOREARM AT the end of lecture the student should able to know about: Different vessels & nerves in forearm Location, destination, course & relations of radial and ulnar arteries & their branches in forearm Deep veins of forearm and their tributaries. Location, destination, course & relations of ulnar, radial and median nerves & their branches in forearm. ARTERIES OF FOREARM AND • Radial artery • Ulnar artery RADIAL ARTERY • One of the terminal branches of the brachial artery • Arises from the brachial artery at the level of the neck of the radius • • • • • • • • COURSE OF RADIAL ARTERY Travels along the radial side of the forearm Winds backward around the carpus to the lateral side Passes below the tendons of the abductor pollicis longus and the extensor pollicis longus and brevis Reaches the upper end of the space between the metacarpal bones of the thumb and the index finger TERMINATION OF THE RADIAL ARTERY Passes through the two heads of the first dorsal interosseous and enter into the palm Crosses the metacarpal bones and reaches the ulnar side Joins the deep volar branch of the ulnar artery Forms the deep volar arch of the palm DIVISIONS • The course of radial artery is divided into the: 1. Radial artery in the forearm 1. Radial artery on the dorsum of the wrist • • • • • • 1. Radial artery in the hand RADIAL ARTEY IN THE FOREARM Extends from the neck of the radius to the styloid process of the radius In the proximal part it is medial and in the lower part it is in front of the Radius The Radial artery is accompanied by the venae commitantes throughout its whole course ANTERIOR RELATIONS IN FOREARM Proximal part is covered by the brachialis Lower part of the radial artery is superficial Anterior to it is skin, superficial and deep fascia POSTERIOR RELATIONS OF THE RADIAL ARTERY IN THE FOREARM • Biceps brachii • Supinator • Pronator teres • Radial head of the flexor digitorium sublimis • Flexor pollicis longus • Pronator quadratus • Radial bone RADIAL ARTERY AT THE WRIST • Reaches the wrist by passing between the radial collateral ligament of wrist and the abductor pollicis longus and extensor pollicis brevis BRANCHES OF THE RADIAL ARTERY Branches in the forearm 1. Radial recurrent 2. Muscular 3. Volar carpal 4. Superficial volar BRANCHES OF RADIAL ARTERY IN THE FOREARM • Radial recurrent • Arises from radial artery just below its origin and ascend on supinator and then between brachialis and brachioradialis • Anastomose with radial collateral branch of profunda brachii artery • Muscular Palmar carpal • Joins the palmar carpal branch of ulnar to form volar carpal arch Superficial palmar branch • Passes through the thenar muscle and anastomoses with superficial branch of ulnar artery to complete superficial palmar arterial arch BRANCHES OF THE RADIAL ARTERY AT THE WRIST Dorsal carpal • Join the dorsal carpal branch of ulnar artery and the dorsal terminal branch of anterior interosseous artery st 1 dorsal metacarpal ULNAR ARTERY • Arises from the brachial artery at the level of the radial neck • Travel on the ulnar side of the forearm and reach midway between the elbow and the wrist • Crosses the transverse carpal ligament on the radial side of the Pisiform bone, and immediately divides into two branches that form Superficial and deep volar arches RELATIONS • Deeply lying structure • It is accompanied by the venae comitantes on both the sides through out its course • Relations in forearm • Relation at wrist RELATION OF ULNAR ARTERY IN FOREARM • Pronator teres • Flexor carpi radialis • Palmaris longus • Flexor digitorium sublimis POSTERIOR RELATION OF ULNAR ARTERY IN FOREARM • It lies on the • Brachialis • Flexor digitorium profondus RELATIONS IN WRIST • At the wrist it lies on the transverse carpal ligament and it is medial to the pisiform bone and ulnar nerve is some what posterior to it BRANCHES OF THE ULNAR ARTERY The branches are arranged as under • Branches in the forearm • At the wrist • In the hand • BRANCHES OF THE ULNAR ARTERY IN FOREARM • Anterior recurrent • Posterior recurrent • Common interosseous • Muscular BRANCHES OF THE ULNAR ARTERY IN FOREARM Anterior recurrent • Anastomose with inferior ulnar collateral Posterior recurrent • Anastomoses with superior ulnar collateral BRANCHES OF THE ULNAR ARTERY IN FOREARM Common interosseous • Arises from lateral side of ulnar artery and divides into: – Anterior interosseous artery • Descends with anterior interosseous nerve in front of interosseous membrane • Perforate the interosseous membrane to anastomose with posterior interosseous and joins dorsal carpal network BRANCHES OF THE ULNAR ARTERY IN FOREARM b)Posterior interosseous artery • Gives rise to interosseous recurrent artery that anastomose with middle collateral, a branch of profunda brachii • Descends behind the interosseous membrane • Anastomose with anterior interosseous BRANCHES AT THE WRIST • Volar carpal • Joins the volar (palmar) carpal branch of radial to form palmar carpal arch • Dorsal carpal • Joins the dorsal carpal branch of radial artery VENAE COMMITANT IN FOREARM • Radial and ulnar arteries are accompanied by the venae comitantes on both the sides throughout their course • Join to form venae commitant of brachial vein NERVES OF THE FOREARM • Ulnar nerve – at the elbow the ulnar nerve is at the dorsum of the medial epicondyles – enters the forearm between the two heads of the flexor carpi ulnaris superficial to the posterior and oblique part of the ulnar collateral ligament. – gives articular branches to the elbow joint NERVES OF THE FOREARM • Muscular branches of the ulnar nerve: – usually two muscular branches – flexor carpi ulnaris and – medial half of the flexor digitorium profundus. • Palmar Cutaneous branch – it arises at the mid of the forearm, – some times supply the Palmaris Brevis. • Median nerve – enters the forearm between the two heads of the Pronator teres. • Anterior interosseous nerve – with anterior interosseous artery it descends anterior to the interosseous membrane NERVES OF THE FOREARM • Radial nerve: – desends in the arm behind the third part of axillary artery and upper part of the brachial artery. – passes through triangular space with the profunda brachii artery. • • – On lateral side of the forearm it pierces the lateral intermuscular septum – In the triangular space, gives the posterior Cutaneous nerve of the arm. It supplies the flexor Pollicis longus and lateral part of the flexor digitorium profundus. It supplies all the flexors of the forearm superficial muscles except the flexor carpi ulnaris, i.e. Pronator teres, flexor carpi radialis, flexor digitorium superficialis, Palmaris longus. • Radial nerve: – supplies the extensor carpi radialis Brevis and – the supinator muscle. • Posterior interosseous nerve: – deep terminal branch of the radial nerve. – supplies the supinator and the extensor carpi radialis Brevis it also supplies • Extensor digitorium, extensor digiti minimi, extensor carpi ulnaris. • Extensor Pollicis longus • Abductor Pollicis longus and extensor polices Brevis. REFERENCE HUMAN ANATOMY KLM 6TH EDITION