Hand Anatomy PDF

©  The Hand Dr. Sean McWatt, PhD [email protected] www.fineartprint s.nl/handwiththe muscles.html Learning Outcomes By the end of this lesson, you will be able to… Identify and describe the bones, joints, and ligaments...

©  The Hand Dr. Sean McWatt, PhD [email protected] www.fineartprint s.nl/handwiththe muscles.html Learning Outcomes By the end of this lesson, you will be able to… Identify and describe the bones, joints, and ligaments related to the hand, and explain the basic movements that occur at the digits Identify the intrinsic muscles of the hand, explain their innervations, and describe their functions Predict functional implications of nervous and musculoskeletal injuries to the hand Regions of the Upper Limb Deltoid region Shoulder Scapular Arm region Anterior and posterior compartments Axillary region Armpit Cubital fossa Elbow We will run through the anatomy of the upper limb according to these regions, Forearm Anterior and posterior from proximal to distal. compartments Carpal region Wrist Dorsal Palmar Hand Back Palmar and dorsal Gilroy, Anatomy: An Essential Textbook, Copyright © 2013 by Thieme Posterior view © 2010, Icon Learning Systems, LLC. A subsidiary of MediMedia, USA, Inc. All right reserved Bones of the Upper Limb Clavicle Sternoclavicular joint The bones of the hand include the Shoulder joint metacarpals and phalanges. The fingers Scapula each have a proximal, middle, and distal phalanx, while the thumb only has Humerus proximal and distal phalanges. The carpals articulate with the metacarpals Elbow joint at the carpometacarpal (CMC) joints, the metacarpals articulate with the phalanges Radius at the metacarpophalangeal (MCP) joints, and the phalanges articulate with each Ulna other at the interphalangeal (IP) joints. Wrist joint Carpal bones MCP joints IP joints Bones of the hand and digits Anterior view Posterior view Gilroy, Anatomy: An Essential Textbook, Copyright © 2013 by Thieme Orientation and Movements Hand Joints D Extensor digitorum m. Merging with extensor expansion Transverse view D Acts at everything proximal to DIPs Phalanges Distal M interphalangeal joints (DIP) P Flexor digitorum P profundus m. Proximal D Acts at everything interphalangeal proximal to DIPs joints (PIP) Digital collateral Flexor digitorum P superficialis m. ligaments Acts at everything proximal to PIPs Metacarpophalangeal III joints (MCP) Metacarpals Carpometacarpal The joints of the digits Joints (CM) are supported by the Carpals digital collateral ligaments. Anterior view Gilroy, Anatomy: An Essential Textbook, Copyright © 2013 by Thieme Orientation Midline III Distal interphalangeal Instead of anterior and joints (DIP) posterior, we use the terms Proximal palmar and dorsal when Interphalangeal joints interphalangeal are hinge joints joints (PIP) referring to the hand. Interphalangeal Also, we consider each hand joint (IP) isolation when describing Metacarpophalangeal Palm joints are condyloid joints movements of the digits, with Palmar aponeurosis reference to the midline of the hand rather than to anatomical position of the body. Metacarpophalangeal joints (MCP) Anterior (palmar) view Agur and Dalley, Grant’s Atlas of Anatomy, 13th Ed. Copyright © 2013 by Lippincott Williams and Wilkins Actions of the Fingers Flexion and extension Flexion and extension Anterior and posterior movement Anterior and posterior movement Occurring at the Occurring at the Metacarpophalangeal jj. Interphalangeal jj. The interphalangeal Lateral view joints can only facilitate Lateral view flexion and extension. Metacarpophalangeal Abduction joints can facilitate Adduction Movement away from flexion, extension, Movement toward midline of the hand adduction and midline of the hand Occurring at the abduction. Occurring at the metacarpophalangeal jj. metacarpophalangeal jj. Anterior view Anterior view Drake, Gray’s Anatomy for Students, 2nd Ed., Copyright © 2009 by Churchill Livingstone  Actions of the Thumb Anterior view Lateral view The thumb has its own orientation and Note: Abduction axis of motion. Extension Flexion The fifth digit also Adduction performs some opposition and reposition Anteromedial view Saddle joint Occurring at the Occurring at the metacarpophalangeal j. carpometacarpal j. and interphalangeal j. Reposition Opposition Movement away Movement toward Opposition allows from the fifth digit the fifth digit us to perform Anterior (palmar) view sophisticated fine Occurring at the carpometacarpal j. Agur and Dalley, Grant’s Atlas of Anatomy, 13th Ed. Copyright © 2013 by Lippincott Williams and Wilkins motor actions and grip tools. Drake, Gray’s Anatomy for Students, 2nd Ed., Copyright © 2009 by Churchill Livingstone Muscles of the Hand NOTE! I have given you very detailed information about the muscles’ attachments. These are there for your reference and explanation purposes, but you do not need memorize them. You will find a muscle chart at the end of the lecture with the detail that you are expected to know. Thenar Eminence The thenar Innervation: eminence is made Recurrent branch of up of the intrinsic median n. (C5–T1) muscles that move the thumb. Flexor pollicis brevis m. Origin: Carpals Insertion: Proximal phalanx They are Abductor pollicis brevis m. Origin: innervated by Carpals the recurrent Insertion: Proximal phalanx branch of the median n. Opponens pollicis m. Origin: Carpals Insertion: 1st metacarpal Anterior (palmar) views Agur and Dalley, Grant’s Atlas of Anatomy, 13th Ed. Copyright © 2013 by Lippincott Williams and Wilkins Hypothenar Eminence The hypothenar Abductor digiti minimi m. eminence is made up of Origin: Carpals the intrinsic muscles Insertion: that move the fifth digit Proximal phalanx and are innervated by the ulnar n. Flexor digiti minimi m. Origin: Carpals The opponens digiti Innervation: Insertion: minimi m. is small, and Proximal phalanx Deep branch many people don’t of ulnar n. (C8–T1) even have one. Opponens digiti minimi m. Origin: Carpals Insertion: 5th metacarpal Anterior (palmar) view Agur and Dalley, Grant’s Atlas of Anatomy, 13th Ed. Copyright © 2013 by Lippincott Williams and Wilkins Long Flexor Tendons Lumbrical mm. Origin: Flexor digitorum Tendons of FDP superficialis m. Insertion: Origin: Digits 2–5 Medial epicondyle (CFO), radius Insertion: Middle phalanges Flexor digitorum profundus m. Origin: The lumbrical mm. originate Ulna, interosseus membrane Insertion: on the tendons of the flexor Distal phalanges digitorum profundus m. Anterior view Gilroy, Anatomy: An Essential Textbook, Copyright © 2013 by Thieme  Central Compartment ‘Thumb side’ Lateral Innervation: Innervation: Deep branch Median n. of ulnar n. (C5–T1) (C8–T1) The medial two lumbrical Medial views Drake, Gray’s Anatomy for Students, 2nd Ed., mm. are innervated by the Copyright © 2009 by Churchill Livingstone ulnar n., whereas the lateral two lumbrical mm. are MCP joint innervated by the median n. Flexion Lumbrical mm. Origin: Tendons of FDP IP joints Insertion: Extension Digits 2–5 Anterior (palmar) view Agur and Dalley, Grant’s Atlas of Anatomy, 13th Ed. Copyright © 2013 by Lippincott Williams and Wilkins  Intrinsic Compartment Palmar interosseus mm. Origin: Metacarpals Insertion: Digits 2, 4, and 5 Innervation: ‘P.AD.’ Deep branch of ulnar n. (C8–T1) Dorsal interosseus mm. The interosseus Origin: Metacarpals muscles lie between Insertion: Digits 2–4 the metacarpal bones of the hand. ‘D.AB.’ Drake, Gray’s Anatomy for Students, 2nd Ed., Copyright © 2009 by Churchill Livingstone Anterior (palmar) views © 2010, Icon Learning Systems, LLC. A subsidiary of MediMedia, USA, Inc. All right reserved Agur and Dalley, Grant’s Atlas of Anatomy, 13th Ed. Copyright © 2013 by Lippincott Williams and Wilkins Thenar Eminence (Revisited) Innervation: Deep branch of ulnar n. (C8–T1) Adductor pollicis m. Origin: While the other thenar muscles Metacarpals and carpals Insertion: are innervated by the recurrent Proximal phalanx branch of the median n., the adductor pollicis m. is an 7 exception… Transverse head Oblique head …it gets its innervation from the deep branch of the ulnar n. Anterior (palmar) view Agur and Dalley, Grant’s Atlas of Anatomy, 13th Ed. Copyright © 2013 by Lippincott Williams and Wilkins Simplified Muscle Chart Attachments Muscle Group Muscle Origin Insertion Main action(s) Innervation Abductor pollicis brevis Abduction (thumb) Proximal phalanx Flexor pollicis brevis Carpals Flexion (thumb) Median n. (recurrent) Thenar eminence Opponens pollicis 1st metacarpal Opposition (thumb) Adductor pollicis Carpals, metacarpals Proximal phalanx Adduction (thumb) Ulnar n. (deep branch) Abductor digiti minimi Abduction (‘pinky’) Proximal phalanx Hypothenar eminence Flexor digiti minimi Carpals Flexion (‘pinky’) Ulnar n. (deep branch) Opponens digiti minimi 5th metacarpal Opposition (‘pinky’) Central compartment Lumbricals Tendons of FDP Extensor expansions Flexion (MCPs), extension (IPs) Ulnar n., median n. Palmar interossei Adduction (digits) Interosseus compartment Metacarpals Proximal phalanges Ulnar n. (deep branch) Dorsal interossei Abduction (digits) Ulnar n. Other Palmaris brevis Palmar aponeurosis Skin of medial palm Tenses skin of palm (superficial branch) Neurovasculature Ulnar Nerve Ulnar canal Carpal Digital tunnel branches Claw hand Ulnar n. injury at wrist Transverse view Gilroy, Anatomy: An Essential Textbook, Copyright © 2013 by Thieme Palmaris brevis m. Innervation: Origin: Superficial ‘Funny bone’ Palmar aponeurosis branch of ulnar n. Impact to ulnar n. Insertion: (C8–T1) Skin Superficial Deep branch branch The ulnar n. is responsible for innervating the majority of intrinsic muscles in the hand. Ulnar n. Agur and Dalley, Grant’s Atlas of Anatomy, 13th Ed. Drake, Gray’s Anatomy for Students, 2nd Ed., Copyright © 2009 by Churchill Livingstone Copyright © 2013 by Lippincott Williams and Wilkins Anterior (palmar) view © 2010, Icon Learning Systems, LLC. A subsidiary of MediMedia, USA, Inc. All right reserved Median Nerve Ulnar canal Carpal tunnel Transverse view Gilroy, Anatomy: An Essential Textbook, Copyright © 2013 by Thieme Ape hand Median n. injury at wrist Palmar and digital branches Recurrent The median n. is branch of responsible for median n. ‘Million-dollar nerve’ innervating some intrinsic muscles on the Median n. lateral side of the hand. C5–T1 Drake, Gray’s Anatomy for Students, 2nd Ed., Copyright © 2009 by Churchill Livingstone Anterior (palmar) view © 2010, Icon Learning Systems, LLC. A subsidiary of MediMedia, USA, Inc. All right reserved Arteries Digital aa. Recall, the blood supply to the hand comes from connections between the ulnar a. (terminating as the superficial Principis palmar arch) and radial a. (terminating pollicis a. as the deep palmar arch). Deep and superficial palmar arches The arches give off digital aa. and the principis pollicis a., which supply the digits. Ulnar a. Radial a. Anterior (palmar) view Drake, Gray’s Anatomy for Students, 2nd Ed., Copyright © 2009 by Churchill Livingstone  Anatomical ‘Snuff Box’ Tendon of Extensor pollicis Anatomical longus m. ‘snuff box’ Lateral view Radial a. Tendon of Abductor pollicis Superficial Tendon of longus m. Extensor pollicis branch of brevis m. radial n. Radial n. cutaneous innervation Scaphoid fracture The scaphoid bone is palpable Radial a. Scaphoid bone within the anatomical ‘snuff-box’. Scaphoid fractures can lead to Radial a. avascular necrosis (tissue death). Anterior (palmar) view © 2020 AMBOSS Drake, Gray’s Anatomy for Students, 2nd Ed., Copyright © 2009 by Churchill Livingstone Nerve Map Summary Axillary n. C5–C6 Medial cutaneous nn. Axillary n. of the arm and C5–C6 forearm From medial cord Nerve maps are Musculocutaneous n. different from C5–C6 (lateral antebrachial) dermatomes! Radial n. Musculocutaneous n. C5–T1 C5–C6 (lateral antebrachial) Nerves can carry fibers Radial n. C5–T1 from multiple spinal levels and, therefore, contribute Ulnar n. C8–T1 to several different Ulnar n. dermatomes C8–T1 Median n. Median n. C5–T1 C5–T1 Posterior view Anterior view Gilroy, Anatomy: An Essential Textbook, Copyright © 2013 by Thieme Dermatome Summary Dermatomes are based on embryological development of spinal segments. Moore. Clinically Oriented Anatomy, 7th Ed. Copyright © 2014 by Lippincott Williams and Wilkins Dermatome and Myotome Assessment ASIA scale Uses dermatomes and myotomes to diagnose spinal cord injury American Spinal Injury Association Learning Outcomes By now, you should better understand how to… Identify and describe the bones, joints, and ligaments related to the hand, and explain the basic movements that occur at the digits Identify the intrinsic muscles of the hand, explain their innervations, and describe their functions Predict functional implications of nervous and musculoskeletal injuries to the hand  © [email protected]