Forearm and Hand By Dr Anita Rani Anatomy

Forearm and Hand By: Dr Anita Rani Anatomy Lecture 7 th November 2016

Lesson Plan • • • Identify skeleton and joints Muscles : attachments and location Action of Muscles on joints Nerves: course and branches Arteries : course and branches Fascia Applied Revision Questions

Skeleton and Joints

Muscles: Forearm 8 • Superficial : cross elbow 1. Pronator teres 9. Supinator 2. Flexor carpi radialis 10. Brachioradialis 3. Palmaris longus 4. Flexor carpi ulnaris Intermediate 5. Flexor digitorum Deep: superficialis 6. Flexor Pollicis Longus 7. Flexor digitorum Profundus 8. Pronator Quadratus

Muscles : Hand 20 Thenar muscles: 4 Abductor pollicis brevis Flexor pollicis brevis Opponens pollicis Adductor pollicis Hypothenar muscles: 4 Abductor Digiti minimi Flexor digiti minimi Opponens digiti minimi Palmaris brevis Lumbricals: 4 with tendons of FDP Interossei: Palmar 4 Dorsal 4

Supinator

Pronator Quadratus

Flexor pollicis longus

Flexor Digitorum Profundus

Flexor digitorum superficialis

Pronator teres

Palmaris longus

Flexor carpi ulnaris & radialis

Brachioradialis

Thenar & Hypothenar muscles

Thenar & Hypothenar Muscles

lumbricals

Interossei dorsal palmar

Actions • Elbow: Flexion : muscle crossing front of elbow BR, PT FCR, FCU, PL, FDS

Actions • Radio-ulnar joints Pronation: PT, PQ Supination: Supinator

Actions • at wrist joint • Flexion: all muscles except…. • Abduction: FCR • Adduction: FCU

Actions • at carpometacarpal joints: Ist: Abduction: APB Adduction: Adductor pollicis • Flexion: Flexor pollicis longus, flexor pollicis brevis • Opposition: opponens pollicis

Actions Metacarpophalangeal joints: • Flexion: FDS, FDP, lumbricals, PI and DI • Abduction: Dorsal interossei [ DAB] • Adduction: Palmar interossei [PAD]

Actions Inter-phalangeal joints: • Flexion: • Proximal: FDS • Distal: FDP • Extension: Lumbricals, Dorsal and Palmar interossei

Nerves: Ulnar, Median and Radial

Nerves: Ulnar • Elbow : lies behind medial epicondyle • Enters forearm by passing b/w 2 heads of FCU • In forearm runs b/w FDP and FDS • Enters palm by passing superficial to flexor retinaculum b/w pisiform and ulnar vs • Divides in to superficial and deep terminal branches

Ulnar nerve Contd… • Superficial branch supply Palmaris brevis and skin of medial 1 &1/2 fingers. • Deep branch passes backwards b/w flexor and abductor digiti minimi. • Runs in the concavity of deep palmar arch. • Ends by supplying adductor pollicis.

Ulnar Nerve

Ulnar nerve in Hand

Ulnar Nerve: branches/ supply 1. 2. 3. 4. 5. 6. 7. 8. 9. FCU medial half of FDP Palmaris brevis 3 hypothenar muscles 3 rd and 4 th lumbricals All interossei Adductor pollicis Skin over hypothenar eminence. Skin of volar aspect of 1 & ½ fingers 10. Skin of dorsum of hand proximal parts of medial 2 & ½ fingers

Cutaneous innervation of Ulnar nerve

Median Nerve • Main nerve of forearm • In cubital fossa lies medial to brachial artery • Enters forearm by passing between 2 heads of pronator teres • Separated from ulnar artery by deep head of pronator teres • Runs on the surface of FDP deep to FDS • 5 cm above flexor retinaculum lies b/w FCR & FDS • Overlapped by the tendon of Palmaris longus

Median nerve

Nerves: Median • Enters the palm by passing deep to flexor retinaculum in carpal tunnel • Breaks into medial and lateral branch • Lateral branch gives off recurrent branch that curve around distal border of FR to supply thenar muscles & 3 digital branches • Medial branch gives out 2 digital branches

Median Nerve : branches/supply • Muscles: PT, FCR, PL, & FDS • Via anterior interosseous nerve: FPL, PQ & radial half of FDP • Palmar cutaneous branch: skin over thenar eminence & central part of palm In Hand: 5 muscles: 3 thenar muscles and 2 lumbricals skin of lateral 3 & ½ digits

Cutaneous innervation : Median nerve

Arteries of forearm and hand Nerves: Median

Superficial and Deep Palmar Arches

Carpal Tunnel

Flexor Retinaculum

Palmar Aponeurosis and synovial sheaths of tendons

Ulnar nerve injury • Which muscles are paralysed? • What do you understand by deformity?

Median nerve injury

Which of the following muscle of forearm helps in flexion at elbow? • • a. flexor digitorum profundus b. flexor pollicis longus C. pronator quadratus D. pronator teres

Which of the following nerve supplies skin over terminal phalanx of index finger? a. b. c. d. Median nerve Ulnar nerve Radial nerve Musculocutaneous nerve