Upper Limb Muscles PDF

Anatomy of Upper Limb Muscles of Hand By Dr. Hassan Mohammed Rizk (Ph.D.) Associate Professor of Human Anatomy and Embryology  Case Study UPPER LIMB Muscles of Hand By Dr. Hassan Rezk September 7, 2024 2  Objecti...

Anatomy of Upper Limb Muscles of Hand By Dr. Hassan Mohammed Rizk (Ph.D.) Associate Professor of Human Anatomy and Embryology  Case Study UPPER LIMB Muscles of Hand By Dr. Hassan Rezk September 7, 2024 2  Objectives: by the end of this lecture the student must understand the following knowledge: UPPER LIMB Identify the shape and attachments of Palmar aponeurosis. Identify the Gross structure of the muscles of compartments of the hand (groups, names of the muscles, their arrangement, nerve supply & action). Mention the Full details (origin, insertion, nerve supply & action) of the following ONLY: 1. Four Palmar Interossei. 2. Four Dorsal Interossei. 3. Four Lumbricals. Identify the shape and attachments of Extensor Hoods. Muscles of Hand By Dr. Hassan Rezk September 7, 2024 3  Objective # ( 1 ) Palmar Aponeurosis ▪ Definition: It is a triangular condensation of deep fascia that covers the palm and is UPPER LIMB anchored to the skin. ▪ The apex of the triangle: ✓ Directed proximally. ✓ Continuous with the palmaris longus tendon. ▪ The base of the triangle: ✓ Directed distally. ✓ Fibers project into each of the index, middle, ring, and little fingers. ✓ Transverse fibers interconnect the longitudinally arranged bundles. Flexor retinaculum ▪ Function: Protect Vessels, nerves, and long flexor tendons lie deep to the palmar palmaris longus tendon aponeurosis in the palm. Muscles of Hand By Dr. Hassan Rezk September 7, 2024 4  Objective # ( 2 ) Muscle Groups of the Hand UPPER LIMB Extrinsic Muscles of the Hand Intrinsic Muscles of the Hand ▪ Long tendons of the muscles of the forearm. Superficial muscle Deep muscle ▪ The tendons that cross the dorsal and Palmaris Brevis ventral surfaces of the wrist joint. Thenar Intermediate Hypothenar muscles muscles muscles Muscles of Hand By Dr. Hassan Rezk September 7, 2024 5  Deep Intrinsic Muscles of the Hand Thenar muscles Intermediate muscles Hypothenar muscles 1) Abductor Pollicis Brevis. 1) Adductor Pollicis. Abductor Digiti Minimi. 2) Flexor Pollicis Brevis. 2) Four Dorsal Interossei. Flexor Digiti Minimi. 3) Opponens Pollicis. 3) Four Palmar Interossei. Opponens Digiti Minimi. 4) Four Lumbricals. UPPER LIMB Muscles of Hand By Dr. Hassan Rezk September 7, 2024 6 UPPER LIMB Muscles of Hand By Dr. Hassan Rezk September 7, 2024 7  General Characters for Intrinsic Muscles of the Hand ▪ Occur entirely in the hand. UPPER LIMB ▪ Mainly execute precision movements (“precision grip”) with the fingers and thumb. ▪ Are innervated by the deep branch of the ulnar nerve except for: 1) Three thenar. 2) Two lateral lumbrical muscles. innervated by the median nerve. Muscles of Hand By Dr. Hassan Rezk September 7, 2024 8  Objective # ( 3 ) Interossei & Lumbrical Muscles of Hand What is the Idea & How we can Study? UPPER LIMB Dorsal Interossei Palmar Interossei Double Head Single Head D D ABduction P ADduction Muscles of Hand By Dr. Hassan Rezk September 7, 2024 9  D ABduction   UPPER LIMB 2 3 4 1 How many abductors for Pollex? How many abductors for Digiti minimi? 2 1 Dorsal surface of Hand Muscles of Hand By Dr. Hassan Rezk September 7, 2024 10  Dorsal Interossei Number ▪ Arranged 1st,2nd,3rd & 4th from lateral to medial UPPER LIMB Site ▪ Dorsum of the hand ▪ Two heads from shafts of adjacent metacarpal Origin bones. Insertion ▪ Inserted in both the base of the proximal phalanx and into the extensor hood of its related digit. ▪ 1st: inserted into the lateral side of the index finger. ▪ 2nd& 3rd: inserted into the lateral and medial sides , respectively, of the middle finger. ▪ 4th: inserted into the medial side of the ring finger. Nerve Supply ▪ Deep branch of ulnar Abductors of the index, middle, and ring fingers, at Action the metacarpophalangeal joints. Muscles of Hand By Dr. Hassan Rezk September 7, 2024 11   UPPER LIMB P ADduction 3 4 How many adductors for Digiti minimi? How many adductors for Pollex? NO 1 Palmar surface of Hand Muscles of Hand By Dr. Hassan Rezk September 7, 2024 12  Palmar Interossei Number ▪ Three (or four) palmar interossei. ▪ Arranged 1st,2nd,3rd & 4th from lateral to medial Site ▪ anterior to dorsal interossei, Origin ▪ from the metacarpals of the digits with which each is UPPER LIMB associated ▪ 1st: is rudimentary. When present, it originates from the medial side of the palmar surface of metacarpal I ▪ 2nd: from the medial surface of metacarpal II. ▪ 3rd & 4th: from lateral surfaces of metacarpals IV and V Insertion ▪ 1st: inserted into both the base of the proximal phalanx of the thumb and into the extensor hood. ▪ 2nd: inserted into the medial side of the extensor hood of the index finger. ▪ 3rd&4th: inserted into the lateral sides of the respective extensor hoods. Nerve Supply ▪ Deep branch of ulnar Action Adduct the thumb, index, ring, and little fingers with respect to a long axis through the middle finger. The movements occur at the metacarpophalangeal joints. Muscles of Hand By Dr. Hassan Rezk September 7, 2024 13 UPPER LIMB 2 3 1 4 F.D.P. Lumbricals Muscles of Hand By Dr. Hassan Rezk September 7, 2024 14  Lumbricals ▪ Four Number ▪ Arranged 1st,2nd,3rd & 4th from lateral to medial originate from the tendons of the flexor digitorum Site profundus in the palm ▪ 1st&2ndlumbricals: UPPER LIMB ✓ from the lateral side of flexor digitorum profundus tendons associated with the index and middle fingers respectively. Origin ▪ 3rd & 4th lumbricals: ✓ from the sides of flexor digitorum profundus tendons associated with the middle and ring fingers and the ring and little fingers , respectively. ▪ pass dorsally around the lateral side of each finger, and insert into the extensor hood. Insertion ▪ The lumbricals are unique because they link flexor tendons with extensor tendons. ▪ 1st&2nd lumbricals are innervated by muscular & Nerve cutaneous branches of the median nerve in hand. Supply ▪ 3rd&4th lumbricals are innervated by the deep branch of the ulnar nerve in hand. 1) Flexing metacarpophalangeal joints Action 2) Extending interphalangeal joints. Muscles of Hand By Dr. Hassan Rezk September 7, 2024 15  Objective # ( 4 ) Extensor Hood (Dorsal Digital Expansion) Definition: connective tissue mass which forms insertion to tendons of: 1. All long extensors of forearm. UPPER LIMB 2. Interossei. 3. Lumbricals. Formation: All The tendons pass onto the dorsal aspect of the digits and expand over the proximal phalanges to form “extensor hood”. Parts: Each extensor hood is inverted triangular (apex is directed distally), with: 1) Two collateral ligaments: attached to the distal phalanx, 2) Central ligament: attached to the middle phalanx of each finger. 3) Base: directed distally and wrapped around the sides of the metacarpophalangeal joint. Function: a) Flexion of metacarpophalangeal joints. b) Extension the interphalangeal joints. Muscles of Hand By Dr. Hassan Rezk September 7, 2024 16  Distal Phalanx Central Ligament Middle 2 Collateral Ligaments UPPER LIMB Phalanx Apex Proximal Phalanx Body Base Muscles of Hand By Dr. Hassan Rezk September 7, 2024 17  Clinical Correlation UPPER LIMB Muscles of Hand By Dr. Hassan Rezk September 7, 2024 18  Clinical Correlation UPPER LIMB ❑ Scaphoid becomes palpable within the snuffbox. ▪ This position enables the physician to palpate the bone to assess for a fracture. ❑ Pulse of the radial artery can also be felt in the snuffbox. Muscles of Hand By Dr. Hassan Rezk September 7, 2024 19  Case Scenario (Staff Question) A 25-year-old male athlete is admitted to the emergency UPPER LIMB department after a bad landing in the pole vault. Radiographic examination of his hand reveals a fractured carpal bone in the floor of the anatomic snuffbox. Which bone has most likely been fractured? A. Triquetral B. Scaphoid C. Capitate D. Hamate E. Trapezoid Muscles of Hand By Dr. Hassan Rezk September 7, 2024 20  Reference UPPER LIMB Gray's anatomy for students, 3rd edition. ISBN: 978-0-7020-5131-9 Copyright© 2015, 2010, 2005 by Churchill Livingstone, an imprint of Elsevier Inc. Chapter 7 Muscles of Hand By Dr. Hassan Rezk September 7, 2024 21 UPPER LIMB Muscles of Hand By Dr. Hassan Rezk September 7, 2024 22