Forearm and Hand Anatomy PDF

Forearm and Hand Dr. Jose Gomez Dr. Andreanna White Assistant Professor Instructor Gross Anatomy Gross Anatomy Department of Medical Foundations Department of Medical Foundati...

Forearm and Hand Dr. Jose Gomez Dr. Andreanna White Assistant Professor Instructor Gross Anatomy Gross Anatomy Department of Medical Foundations Department of Medical Foundations Email: [email protected] Email: [email protected] Kindly email any questions Intended Learning Click to edit Objectives Master title style 1. Identify the bones of the forearm and hand and describe their unique characteristics. 2. Distinguish the types of joints, and describe the movements permitted at each joint. 3. Distinguish between extrinsic and intrinsic muscles of the hand. Identify their origin and insertions, actions, and innervations. 4. Define the boundaries of the anatomical snuffbox and its contents. 5. Define the course and branches of the radial, ulnar and median nerves through the forearm and hand. 6. Identify how damage to a nerve in different regions of the body can have different clinical presentations. 7. Describe the course and branches of the radial and ulnar arteries through the forearm and hand. 8. Identify the course of arterial and venous blood flow in the forearm and hand. 9. Identify the lymphatic drainage from the forearm and hand, identifying the most likely pathways and lymph nodes travelled through. 10. Distinguish the clinical signs/symptoms when damage occurs to a given nerve. 11. Associate the following clinical correlates with their anatomical underpinnings: Colles’ and Smith fractures, stress injuries to the elbow Recommended Reading: Gray’s Anatomy for Students, 4th Edition: Chapter 7 “Upper Limb”, Pages: 680, 681, 761 - 809 Osteology Click to editofMaster the Forearm and Hand title style Please Refer to your Pre-Lab Osteology Quiz This material is needed to understand this lecture, associated activities, and is examinable! Muscles of the Forearm and Hand ClickMuscles of thetitle to edit Master Forearm style Muscle belly located within the forearm. Inserts within the forearm. Function to move the forearm in supination or pronation Examples: Supinator Pronator Quadratus Brachioradialis ClickMuscles of thetitle to edit Master Forearm style Muscle belly located within the forearm. Inserts within the forearm. Extrinsic muscles of the hand Function to move the forearm in supination or (on next slide) pronation ClickExtrinsic & Intrinsic to edit Master Muscles of the Hand title style Extrinsic Intrinsic The proximal muscle tendons and muscle bulk (belly) originates outside of the The muscle bulk (belly) originates within manus (hand) region with distal tendons the hand and inserts within the hand inserting into structures within the hand Anterior views ClickSummary of Muscles to edit Master title style Forearm musculature Muscle belly located and inserts Intrinsic muscles of the hand Extrinsic muscles of the hand within the forearm 3 digitorum muscles: 3 thenar muscles: Flexor digitorum superficialis Abductor pollicis brevis Flexor digitorum profundus Flexor pollicis brevis 3 pronation/supination muscles: Extensor digitorum Opponens pollicis Supinator (supinator brevis) Pronator quadratus 4 extrinsic pollicis muscles: Pronator teres Extensor pollicis longus Extensor pollicis brevis 6 muscles of wrist movement: Adductor pollicis Abductor pollicis longus Palmaris longus Flexor pollicis longus Flexor carpi ulnaris Flexor carpi radialis Extensor carpi ulnaris 4 hypothenar muscles: Extensor carpi radialis brevis Palmaris brevis Extensor digiti minimi Extensor carpi radialis longus Abductor digiti minimi Flexor digiti minimi brevis Brachioradialis (supinator longus) Opponens digiti minimi 4 Lumbricals Extensor indicis 3 Palmar interossei 4 Dorsal interossei Brevis = short muscle bulk Longus = elongated muscle bulk Carpi = refers to carpal region/wrist Digiti minimi = refers to 5th digit Indicis = Refers to 2nd digit of hand Pollicis = refers to 1 digit of hand st Digitorum = refers to digits ClickTissue to edit Layers of the Master title Forearm style Skin outermost layer of the forearm Lateral Superficial fascia Intermuscular subcutaneous layer septum composed of loose Extension of the connective and adipose antebrachial fascia to (fatty) tissue. It contains divide the muscles into cutaneous nerves, compartments superficial veins and lymphatics. Deep fascia of the forearm (antebrachial Radius fascia) Protective covering of dense connective tissue in the forearm enclosing muscles, Ulna neurovasculature, and Interosseous lymphatics. membrane Note: Continuous from the brachial fascia and bicipital aponeurosis proximally and with the flexor retinaculum (transverse/palmar carpal ligament), and the palmar aponeurosis distally) Superior view of transverse cross-section of right forearm ClickFascial Compartments to edit Master title style of the Forearm Interosseous Membrane Lateral of forearm: Intermuscular septum Dense fibrous connective tissue structure located between the radius and ulna bones in the Radius forearm (fibrous joint - syndesmosis) Ulna Together with the bones and the lateral intermuscular septum Interosseous separate the forearm Membrane into two compartments: Superior view of transverse cross-section of right forearm - Anterior - Posterior Anterior view ClickFascial to editCompartments of the Forearm (continued) Master title style Muscle Compartments Function Innervation Type Superficial Anterior Majorly median Compartment Flexors nerve with Anterior & some ulnar Radius Deep Pronators nerve Anterior exceptions Compartment Extensors Posterior & Radial nerve Supinators Ulna Superior view of transverse cross-section of right forearm ClickAnterior Compartment to edit Master title style of the Forearm Compartment Muscles General actions Innervation Pronator teres Palmaris longus Median nerve Superficial Flexor digitorum superficialis Flexor carpi radialis Flexors of the wrist and fingers Flexor carpi ulnaris Ulnar nerve Digits 4 - 5 Pronators of the Flexor digitorum profundus forearm Digits 2 – 3 Deep Flexor pollicis longus Median nerve Pronator quadratus ClickSuperficial Anterior to edit Master Compartment title style Right Forearm Pronator teres Flexor carpi radialis Palmaris longus Flexor carpi ulnaris Flexor digitorum superficialis Anterior view ClickSuperficial Anterior to edit Master Compartment (continued) title style Origin Humeral head: medial epicondyle Ulna head: coronoid process of ulna Pronator teres Insertion Middle portion of lateral radius Innervation Median nerve Pronates forearm Action Helps flex forearm at elbow ClickSuperficial Anterior to edit Master Compartment (continued) title style Origin Medial epicondyle Insertion Flexor retinaculum and palmar aponeurosis Palmaris longus Innervation Median nerve Flexes wrist Action Tenses palmar aponeurosis ClickSuperficial Anterior to edit Master Compartment (continued) title style Humero-ulnar head: medial epicondyle (humerus) and Origin coronoid process (ulna) Radial head: superior portion of shaft of radius Insertion Intermediate phalanx of digits 2 – 5 Flexor digitorum Innervation Median Nerve superficialis Flexes proximal interphalangeal (PIP) joint of digits 2 Action –5 Helps to flex wrist ClickSuperficial Anterior to edit Master Compartment (continued) title style Origin Medial epicondyle of humerus Flexor carpi radialis Insertion Base of 2nd metacarpal Innervation Median Nerve Flexes hand at wrist Action Abducts hand at wrist ClickSuperficial Anterior to edit Master Compartment (continued) title style Origin Humeral head: Medial epicondyle Ulnar head: Olecranon process Pisiform Insertion Hook of hamate Flexor carpi ulnaris 5th metacarpal Innervation Ulnar nerve Flexes hand at wrist Action Adducts hand at wrist ClickDeep to editAnterior Compartment Master title style Right Forearm Flexor digitorum profundus Flexor pollicis longus Pronator quadratus Anterior view ClickDeep to editAnterior Compartment Master title style (continued) Proximal surfaces of medial and anterior surfaces Origin of ulna and interosseous membrane Insertion Bases of distal phalanx of digits 2 – 5 Flexor digitorum profundus Digits 2 – 3: median nerve (via branch - anterior Innervation interosseous nerve) Digits 4 – 5: ulnar nerve Flexes distal interphalangeal (DIP) joint of digits 2 – Action 5 ClickDeep to editAnterior Compartment Master title style (continued) Anterior surface of radius Origin interosseous membrane Insertion Base of distal phalanx of digit 1 (pollex) Flexor pollicis longus Median nerve (via branch - anterior interosseous Innervation nerve) Flexes 1st digit (pollex/thumb) at interphalangeal Action (IP) and metacarpo-phalangeal (MCP) joints ClickDeep to editAnterior Compartment Master title style (continued) Origin Distal ulna Insertion Distal radius Median nerve (via branch - anterior interosseous Innervation nerve) Pronator quadratus Pronates forearm Action Binds ulna & radius together ClickPosterior Compartment to edit Master title style Muscles General Action Innervation Right Forearm Extensor carpi ulnaris Extensor digitorum Extensor digiti minimi Extensors of Brachioradialis the wrist Extensor carpi radialis longus and fingers Extensor carpi radialis brevis Radial nerve Supinators Supinator of the Abductor pollicis longus forearm Extensor pollicis longus Extensor pollicis brevis Extensor indicis Posterior view ClickPosterior Compartment to edit Master title style (continued) Right Forearm Extensor carpi ulnaris Brachioradialis Extensor digitorum Extensor carpi radialis longus Extensor digiti minimi Extensor carpi radialis brevis Posterior view Lateral view ClickPosterior Compartment to edit Master title style (continued) Right Forearm Supinator Abductor pollicis longus Extensor pollicis longus Extensor pollicis brevis Extensor indicis Posterior view ClickPosterior Compartment to edit Master title style (continued) Lateral epicondyle Origin Posterior border of ulna Extensor carpi ulnaris Insertion Dorsal base of 5th metacarpal Radial nerve (via a continuation of the deep Innervation branch of the radial nerve – posterior interosseous nerve) Extends the hand at the wrist Action Adducts the hand at the wrist ClickPosterior Compartment to edit Master title style (continued) Origin Lateral epicondyle Insertion Extensor expansion of digits 2-5 Extensor digitorum Radial nerve (via a continuation of the deep branch Innervation of the radial nerve – posterior interosseous nerve) Primary extension at metacarpophalangeal (MCP) joint digits 2-5 Action Secondary extension at interphalangeal (IP) joints (distal, middle, & proximal phalanges) Helps with extension of the wrist ClickPosterior Compartment to edit Master title style (continued) Origin Lateral epicondyle Insertion Extensor expansion of digit 5 Extensor digiti minimi Radial nerve (via a continuation of the deep Innervation branch of the radial nerve – posterior interosseous nerve) Primary extension at metacarpophalangeal (MCP) joint of digit 5 Action Secondary extension at interphalangeal (IP) joints of digit 5 ClickPosterior Compartment to edit Master title style (continued) Origin Lateral supracondylar ridge of humerus Brachioradialis Insertion Distal lateral radius Innervation Radial nerve Helps flex forearm at the elbow, especially in mid- Action pronated position ClickPosterior Compartment to edit Master title style (continued) Origin Lateral supracondylar ridge of humerus Insertion Dorsal base of 2nd metacarpal Extensor carpi radialis longus Innervation Radial nerve Extend the hand at the wrist Action Abduct the hand at the wrist Active during clenching ClickPosterior Compartment to edit Master title style (continued) Origin Lateral epicondyle Insertion Dorsal base of 3rd metacarpal Extensor carpi radialis brevis Innervation Radial nerve (deep branch) Extend the hand at the wrist Action Abduct the hand at the wrist ClickPosterior Compartment to edit Master title style (continued) Lateral epicondyle of humerus Origin Radial collateral & annular ligament Proximal ulna Supinator Insertion Proximal 1/3 of radius Radial nerve (via the deep branch of the radial Innervation nerve) Action Supinates forearm ClickPosterior Compartment to edit Master title style (continued) Proximal ½ of posterior ulna, radius, & Origin interosseous membrane Insertion Base of 1st metacarpal Abductor pollicis longus Radial nerve (via a continuation of the deep Innervation branch of the radial nerve – posterior interosseous nerve) Abducts thumb Action Extends thumb at carpometacarpal (CMC) joint Posterior Compartment Click to edit (continued) Master title style Middle 1/3 of posterior ulna & interosseous Origin membrane Insertion Dorsal base of distal phalanx of digit 1 Extensor pollicis longus Radial nerve (via a continuation of the deep Innervation branch of the radial nerve – posterior interosseous nerve) Extends distal phalanx of thumb at interphalangeal (IP) joint Action Extends carpometacarpal (CMC) & metacarpophalangeal (MCP) joints ClickPosterior Compartment to edit Master title style (continued) Distal 1/3 of posterior radius & interosseous Origin membrane Insertion Dorsal base of proximal phalanx of digit 1 Radial nerve (via a continuation of the deep Innervation branch of the radial nerve – posterior interosseous Extensor pollicis brevis nerve) Extends proximal phalanx of thumb at the Action metacarpophalangeal (MCP) joint Extends carpometacarpal (CMC) joint ClickPosterior Compartment to edit Master title style (continued) Distal 1/3 of posterior ulna & interosseous Origin membrane Insertion Extensor expansion of digit 2 Radial nerve (via a continuation of the deep Innervation branch of the radial nerve – posterior interosseous nerve) Extensor indicis Extends proximal phalanx of digit 2 Action Extends hand at wrist ClickFascia to edit of Master title style the Wrist The antebrachial fascia thickens towards the wrist to form the fascia of the wrist Anteriorly Posteriorly Flexor retinaculum also known as the transverse/palmar Extensor retinaculum carpal ligament Tendon sheaths are tubular structures that surround and protect tendons as they pass through fibrous channels created by the deep fascia, helping reduce Flexor friction and wear and tear on the retinaculum tendons during movement. Flexor tendon Extensor sheaths tendon sheaths Extensor retinaculum Palmar Dorsal ClickFlexor to edit Retinaculum & the Carpal Tunnel Master title style Flexor retinaculum Extends from the scaphoid and trapezium bones on the radial (lateral) side to the pisiform bone and the hook of the hamate bone on the ulnar (medial) side Converts the concavity formed by the carpal bones into the carpal tunnel, containing 10 structures: - Median nerve - 4 flexor digitorum superficialis tendons - Flexor pollicis longus - 4 flexor digitorum profundus tendons Carpal tunnel Functions: - Prevents bowstringing of tendons - Provides structural support and protection to Superior view of a transverse cross section of the carpal region the contents of the carpal tunnel ClickCarpal Tunneltitle style to edit Master Guyon’s canal/ Ulnar nerve & Ulnar canal/tunnel Flexor carpi artery radialis tendon Flexor Median digitorum nerve superficialis tendons Carpal tunnel Flexor pollicis Flexor digitorum longus tendon profundus tendons Superior view of a transverse cross section of the right carpal region ClickAnatomical Snuffbox to edit Master title style Boundaries: Anterior – abductor pollicis longus & extensor pollicis brevis tendons Posterior – extensor pollicis longus Floor – scaphoid and trapezium Roof – superficial branch of radial nerve & cephalic vein Extensor pollicis longus tendon Contents: Radial artery Radial artery Extensor pollicis Abductor pollicis brevis tendon longus Anatomical snuffbox ClickFascia to editof the Hand Master title style As the deep fascia thickens anteriorly to form the flexor retinaculum, it then continues to the apex of a triangular condensation covering the palm known as the palmar aponeurosis. If present, the apex of the triangle is continuous with the palmaris longus tendon Palmar It is anchored to the skin in distal regions aponeurosis The palmar aponeurosis radiates fibers to extensions at the bases of the digits that project into each finger but to a lesser extent in the thumb. The transverse fibers interconnect the more longitudinally Palmaris longus arranged bundles that continue into the digits tendon Just like the Flexor retinaculum helps prevent bowstringing.  Bowstringing Click to edit Master title style Click Trigger Finger to edit Master title style Name Trigger Finger (stenosing tenosynovitis or stenosing tenovaginosis) Mechanism of Injury A finger or thumb becomes locked in a flexed position. “Why Trigger Finger” Locking occurs when one of the tendons that flex the digit becomes inflamed and swollen, often with a noticeable nodule in the palm The inflamed tendon can move out of the tendon sheath as the finger flexes, however when the tendon is very swollen, it cannot easily move back in as the finger extends, and therefore the digit locks To straighten the digit, one must force the swollen area into the sheath—causing a popping sensation similar to that felt when pulling a trigger Cause Unknown https://3d4medic.al/E4qjBoYn Common in patients with diabetes and rheumatoid arthritis Click Dupuytren’s to edit MasterContracture title style Name Dupuytren’s Contracture Mechanism of Disease of Palmar Fascia & Aponeurosis: Injury Fascial thickening causing shortening of the medial side of the hand Typically in men >50 years old Potentially Genetic Cause Presentation Flexion at metacarpophalangeal (MCP) & proximal interphalangeal (PIP) joint Loss of dexterity and function, and in severe cases requires surgical removal of the abnormal tissue. ClickDorsal to edit Digital Expansions Master title style Click Mallet Finger-title to edit Master “Baseball style Finger” Name Mallet Finger Mechanism of Injury Long Extensor tendon avulsion Presentation Hyperflexion at the distal interphalangeal joint (DIP) Inability to extend the DIP https://3d4medic.al/wGKOUuhn ClickIntrinsic Muscles to edit Master titleof the Hand style Intrinsic muscles of the hand 3 thenar muscles: Abductor pollicis brevis Flexor pollicis brevis Opponens pollicis Adductor pollicis 4 hypothenar muscles: Palmaris brevis Abductor digiti minimi Flexor digiti minimi brevis Opponens digiti minimi 4 Lumbricals 3 Palmar interossei 4 Dorsal interossei ClickThenar Compartment to edit Master title styleof the Hand Palmar view of right hand Flexor pollicis brevis Abductor pollicis Opponens brevis pollicis Superficial layer Middle layer ClickThenar Compartment to edit Master title styleof the Hand (continued) Flexor retinaculum, tubercles of scaphoid & Origin trapezium Insertion Proximal phalanx of digit 1 Innervation Recurrent branch of median nerve Abductor pollicis brevis Action Abduction of the thumb ClickThenar Compartment to edit Master title styleof the Hand (continued) Flexor retinaculum, tubercles of scaphoid & Origin trapezium Insertion Base of 1st proximal phalanx Flexor pollicis brevis Innervation Recurrent branch of median nerve Action Flexes the thumb ClickThenar Compartment to edit Master title styleof the Hand (continued) Flexor retinaculum, tubercles of scaphoid & Origin trapezium Insertion 1st metacarpal Innervation Recurrent branch of median nerve Opponens pollicis Action Opposition towards digit 5 ClickAdductor Pollicis to edit Master title style Palmar view Oblique head: bases of 2nd & 3rd metacarpals, capitate, & adjacent carpals Origin Transverse head: anterior surface of 3rd metacarpal Adductor pollicis Insertion Base of 1st proximal phalanx Innervation Deep branch of ULNAR nerve Action Adducts thumb towards lateral palm Middle layer ClickHypothenar Compartment to edit Master title style of the Hand Palmar view of right hand Opponens Palmaris brevis digiti minimi muscle Abductor Flexor digiti digiti minimi minimi brevis Superficial layer Middle layer  ClickHypothenar Compartment to edit Master title style of the Hand (continued) Palmar aponeurosis and flexor retinaculum Origin (hypothenar eminence) Insertion Dermis of skin on the medial margin of the hand Palmaris brevis Innervation Superficial branch of the ulnar nerve muscle Strengthens palmar grip by wrinkling the skin of Action the ulnar palm  ClickHypothenar Compartment to edit Master title style of the Hand (continued) Origin Pisiform Insertion Base of 5th proximal phalanx Innervation Deep branch of ULNAR nerve Abductor Action Abduction of digit 5 digiti minimi  ClickHypothenar Compartment to edit Master title style of the Hand (continued) Origin Hook of hamate & flexor retinaculum Insertion Base of 5th proximal phalanx Innervation Deep branch of ULNAR nerve Flexor digiti Action Flexes proximal phalanx of digit 5 minimi brevis ClickHypothenar Compartment to edit Master title style of the Hand (continued) Origin Hook of hamate & flexor retinaculum Insertion 5th metacarpal Opponens Innervation Deep branch of ULNAR nerve digiti minimi Action Opposition towards digit 1  Central Click to editCompartment of the Hand: Lumbricals Master title style Origin Tendons of flexor digitorum profundus Insertion Lateral sides of extensor expansions of digits 2-5 Lumbrical Muscles Lumbricals 1 & 2: MEDIAN nerve (medial & lateral Innervation branches) Lumbricals 3 & 4: Deep branch of ULNAR nerve Flex metacarpophalangeal (MCP) joint, extend Action interphalangeal (IP) joints of digits 2-5  Central Click to edit Compartment Master title styleof the Hand: Lumbricals (continued) 1st & 2nd lumbricals The lumbricals cross two joints. They run FDS Lumbrical below the metacarpophalangeal joint FDP from FDP and then rise over the interphalangeal joints to attach to the Dorsal interossei extensor hood. Flexor pollicis longus 3rd and 4th Lumbrical lumbricals Flexor retinaculum Lumbrical FDS = Flexor digitorum superficialis FDP = Flexor digitorum profundus  Central Click Compartment to edit Master title styleof the Hand: Lumbricals (continued)  ClickPalmar to edit Interossei Master title–style Deep Layer Origin Palmar surfaces of 2nd, 4th, & 5th metacarpals 2nd, 4th, & 5th proximal phalanges & extensor Insertion expansions Innervation Deep branch of ULNAR nerve Palmar interossei (3) Adduction of 2nd, 4th, 5th digits & flexion of the Action metacarpophalangeal joint ClickDorsal to editInterossei Master title– style Deep Layer Adjacent surfaces of metacarpals 1st dorsal interossei has origins on 1st and 2nd Origin Dorsal interossei (4) metacarpal Digits 2-4, bases of proximal phalanges & extensor Insertion expansion Deep branch of ULNAR nerve Innervation Abduction of digits 2-4 & flexion at the metacarpophalangeal joint Action ClickInterossei Muscles to edit Master (continued) title style Interossei: Axis at digit 3 Abduction and adduction of the digits Dorsal Interossei ABduct = DAB Palmar Interrosei ADduct = PAD The Neurovascular System of the Forearm and Hand & Associated Clinical Injuries Click Arteries of thetitle to edit Master Forearm style Click Arteries of thetitle to edit Master Forearm style Recurrent interosseous Posterior (ghosted) & anterior interosseous Palmar carpal Superficial branches and deep *Scaphoid palmar bone arches Anterior view 70 ClickArteries to edit Master of thetitle Handstyle Superficial As the radial and ulnar arteries enter the hand palmar arch Proper palmar from the wrist digital arteries they form: 1. Palmar Arches Radial artery of index finger 2. Digital Arteries: 1. Common palmar digital arteries Common 2. Proper digital arteries palmar digital arteries The Palmar Arches Superficial The superficial palmar arch is formed mainly by continuation of palmar arch ulnar artery into hand. It anastomoses with the superficial branch of the radial artery and gives off common palmar Princeps pollicis artery Deep digital artery. palmar arch Radial Ulnar artery artery ClickArteries to edit Master of thetitle Hand style The Palmar Arches Cont’d Superficial palmar The deep palmar arch is formed by continuation archartery past the wrist, posterior to of the radial metacarpal 1, anastomosing with the deep palmar branch of the ulnar artery. Radial artery Deep palmar arch Recurrent branches Deep palmar branch of ulnar a. Princeps pollicis artery 3-4 palmar metacarpal arteries Radialis indicis artery Click Arteries of thetitle to edit Master Forearm style and Hand ClickArteries to edit Master of thetitle Handstyle ClickVeins to editofMaster title style the Forearm The Superficial Veins of the Forearm Click Veins to editof the Hand Master title style The Superficial Veins of the Hand Lymphatic Click to editDrainage ofstyle Master title Upper Limb Lymph from the hand and forearm drain from lymphatic plexuses via superficial channels that accompany the basilic and cephalic veins to a series of nodes around the elbow: - Following basilic vein towards Cubital lymph nodes (Epi/supratrochlear lymph nodes): Cubital nodes → lateral axillary nodes → central axillary nodes → apical axillary nodes → subclavian nodes → thoracic duct (left) or right lymphatic duct - Following cephalic vein towards infraclavicular lymph nodes: Infraclavicular nodes → apical axillary nodes → subclavian trunk → thoracic duct (left) or right lymphatic duct Deep lymphatic drainage follow deep channels draining into: - Infraclavicular lymph nodes: predominantly lateral upper limb and lateral two digits - Humeral/brachial (lateral) lymph nodes draining then towards the axillary lymph nodes: predominantly medial upper limb and medial three digits Click Superficial Lymphatics to edit Master title style of the Upper Limb Superficial Lymphatic vessels (originating from the digital lymphatic vessels of the digits & lymphatic plexus of the palm) Drain from the PALM to the DORSUM of the hand The lymph vessels then ascend through the forearm and arm, converging toward the CEPHALIC and BASILIC veins Lymph following the Lymph following the basilic vein drains to cephalic vein drains the CUBITAL nodes directly into the before draining to INFRACLAVICULAR nodes the HUMERAL (lateral) lymph nodes before Lymph the drains draining to the central directly into the lymph nodes APICAL nodes Lymphatic Click to editdrainage flow Master title Diagram style Infraclavicular Right (or left) venous angle Apex Subclavian Apical Central Humeral/Brachial Subscapular (Posterior) Cubital (Lateral) (Epi/supratrochlear) Pectoral (Anterior) ClickNerves of the Forearm to edit Master title style Radial There are three main nerves of the forearm: nerve 1. Radial Nerve (Lateral) 2. Ulnar Nerve (Medial) Median 3. Median Nerve (Center) nerve Ulnar nerve ClickUlnar to editNerve MasterPathway in the Forearm title style Ulnar nerve Ulnar Nerve passes posterior to the medial epicondyle Flexor Medial “cubital tunnel” of the arm to enter the forearm digitorum epicondyle profundus Flexor carpi ulnaris Enters and descends the forearm by passing between the flexor carpi ulnaris and flexor digitorum profundus DOES NOT PASS THROUGH the carpal tunnel at the Ulnar nerve wrist Passes through a band of tissue called the Ulnar Canal (Guyon’s Canal) ClickUlnar to editNerve MasterInnervation title style PALMAR PALMAR & DORSAL CUTANEOUS SUPERFICIAL BRANCH BRANCHES (not pictured) Supplies sensory to The Ulnar Nerve has three main medial 1 ½ Sensory to skin of medial branches in the hand: digits (palmar & dorsal part of palm & dorsum 1. Palmar & Dorsal Cutaneous surface) (Sensory) 2. Superficial Branch (Sensory) 3. Deep Branch (motor) DEEP BRANCH Motor to all remaining muscles of hand (so, not thenar muscles or lateral 2 lumbricals) ClickClinical Implications to edit Master of Ulnar Nerve Injuries- Ulnar Claw title style Ulnar Claw DAMAGE TO ULNAR NERVE AT WRIST Paralysis of Hypothenar muscles, adductor pollicis, 3rd & 4th lumbricals, & interossei Patient is unable to flex metacarpophalangeal joint of digits 4 &5, & unable to extend interphalangeal joints when trying to straighten fingers; unable to move digit 5 Click to edit Master Clinical title style Implications of Ulnar Nerve Injuries- Ulnar Claw Cont’d Ulnar Claw Cont’d DAMAGE TO ULNAR NERVE AT ELBOW Medial half of flexor digitorum profundus affected in addition to the muscles listed as affecting the wrist. Patient is unable to flex the distal interphalangeal joint of digits 4 & 5, making the “claw” less prominent ➔ ulnar paradox. ClickClinical to edit Master title style Implications of Ulnar Nerve Injuries- Avulsion Fracture Avulsion Fracture of Medial Epicondyle Demographics: Children 9-14 years old Baseball/softball pitchers https://3d4medic.al/Gbe51Lw4 Falls causing severe abduction of an extended elbow Symptoms: Sudden severe onset of pain on inside of elbow Numbness & tingling in forearm & 4th & 5th digits Claw hand deformity Ulnar nerve irritation or injury Click Median Nervetitle to edit Master Pathway style in the Forearm Median Nerve enters the cubital fossa medial to the Median nerve brachial artery Pronator teres: humeral head Flexor carpi radialis Pronator teres: Exits the cubital fossa by passing between the heads of ulnar head Palmaris longus pronator teres Flexor pollicis Flexor longus digitorum Pronator superficialis Moves through the fascial plane between the flexor quadratus Flexor digitorum superficialis & flexor digitorum profundus Median nerve digitorum profundus Palmar cutaneous branch of median n. Continues deep to palmaris longus to ENTER the CARPAL TUNNEL. (Note: The palmar cutaneous branch of the median nerve does not enter the carpal tunnel)  Median Click to Nerve edit Master Innervation title style PALMAR CUTANEOUS PALMAR BRANCHES Sensory to palm Not affected by carpal tunnel The Median Nerve has four main branches in the hand: RECURRENT BRANCH 1. Palmar Cutaneous Branch (Sensory) Motor to thenar muscles 2. Recurrent Branch (Motor) LATERAL BRANCH OF MEDIAN 3. Medial Branch (Motor) NERVE 4. Lateral Branch (Motor) Motor to 1st lumbrical Sensory to palmar & dorsal MEDIAL BRANCHES OF MEDIAN aspect of digit 1 NERVE Motor to 2nd lumbrical Sensory to palmar & dorsal digits 2, 3, & ½ of 4 ClickMedian Nerve:title to edit Master Sensory style Territory ClickSensory Innervation to edit Master of Nerves of the Hand title style Paresthesia over the hypothenar eminence would not occur because it is supplied by the ulnar nerve. The palmar cutaneous branch of the median nerve that supplies innervation to the thenar eminence would not be affected in carpal tunnel syndrome because it branches before and travels above the flexor retinaculum and is therefore not compressed. Dorsal view of the hand Palmar view of the hand Click to edit MasterFracture Supracondylar title style of the Humerus (proximal nerve injury) Mechanism of Injury: Fall onto an outstretched hand Damage to median nerve at the elbow Clinical Implications: Distal shaft fragment displacement (posteriorly) -> Limb Shortening Risk of brachial artery laceration -> Ischemic contracture (Volkmann’s Contracture) Risk of median nerve damage -> Motor & Sensory loss Resulting in “Hand of Benediction” (when making a fist) Click to edit Hand of Master title style Benediction This is the result of asking the patient to make a fist: Only the fourth and fifth digits flex The other fingers which are supplied by the median nerve are unable to flex resulting in the deformity seen here.  Supracondylar Click Fracture to edit Master title style of the Humerus Cont’d Loss of action of the long flexors in the anterior compartment of the arm (except medial half of flexor digitorum profundus & flexor carpi ulnaris as these are innervated by ulnar nerve) & Lateral two lumbricals When patient is asked to make a fist: Inability to flex digits 2 & 3 Ability to flex digits 4 & 5 preserved Loss Functional loss of: Function Retained: 1. Long flexors in 1. Medial half of flexor anterior compartment digitorum profundus 2. Lateral two lumbricals 2. Flexor carpi ulnaris Median nerve palsy: https://3d4medic.al/bZ76Keak Supracondylar fracture of humerus: https://3d4medic.al/5n9BaYuT Click Median to edit Master Nerve title style Injury: Ape Hand Deformity (distal nerve injury) Mechanism of Injury: Damage to Median Nerve at the Wrist Resulting in: Paralysis of thenar muscles & lateral two lumbricals Loss of opposition from digit 1, & weakened digit 1 flexion and abduction “Ape Hand” is due to shape of deformity, as Apes have opposable thumbs Common in suicide attempts Loss Functional loss of: 1. Abductor pollicis brevis Function Retained: 2. Flexor pollicis brevis 1. Flexor digitorum profundus 3. Opponens pollicis 2. Flexor digitorum superficialis 4. Lateral two lumbricals 3. Flexor pollicis longus Click Median Nervetitle to edit Master Injury: styleCarpal Tunnel Syndrome Mechanism of Injury: Any condition that reduces the size / compresses the carpal tunnel E.g. Repetitive movements at the wrist Swelling within the flexor retinaculum Compression of the MEDIAN nerve Symptoms: Wrist flexion elicits pain Wrist extension relieves pain Symptoms worse at night Ape Hand Deformity https://3d4medic.al/1GC8WNKW Loss of sensation of the lateral 3 ½ digits (sometimes) ClickInnervation to edit Master to title the style Palm Ulnar Nerve Median Nerve All digiti minimi muscles: Most pollicis muscles: 1. Flexor digiti minimi 1. Flexor pollicis brevis 2. Opponens digiti minimi 2. Opponens pollicis 3. Abductor digiti minimi 4. Adductor pollicis 3. Abductor pollicis brevis 5. Palmaris brevis 1st and 2nd lumbricals 3rd and 4th lumbricals All interossei muscles Click Radial Nerve title to edit Master Pathway style in the Forearm Superficial branch Enters the forearm between brachioradialis & brachialis Radial nerve Brachioradialis Deep branch Extensor carpi Extensor radialis longus Branches anterior to the lateral epicondyle into deep carpi ulnaris and brevis (motor) & superficial branches (sensory) Supinator Extensor digiti minimi Extensor Superficial branch descends between pronator teres & digitorum Superficial brachioradialis, joining with the radial artery, then curves branch back over brachioradialis distally & divides into many superficial nerves Deep branch penetrates supinator & becomes the posterior interosseous nerve as it leaves supinator Click Radial Nerve title to edit Master Pathway style in the Forearm Cut section of Brachioradialis -> Enters the forearm between brachioradialis & brachialis Branches anterior to the lateral epicondyle into deep (motor) & superficial branches (sensory) Click Radial Nerve title to edit Master Pathway style in the Forearm Enters the forearm between brachioradialis & brachialis Branches anterior to the lateral epicondyle into deep (motor) & superficial branches (sensory) Superficial branch descends between pronator teres & brachioradialis, joining with the radial artery, then curves back over brachioradialis distally & divides into many superficial nerves Deep branch penetrates supinator & becomes the posterior interosseous nerve as it leaves supinator Click Radial Nerve Injury: to edit Master title styleRadial Nerve Palsy & Wrist Drop Radial Nerve Palsy- Mechanism of Injury: Penetrating injuries to the posterior forearm Symptom: Inability to extend the thumb and fingers (MCP joint) No loss of sensation Wrist Drop: Mechanism of Injury: Damage to the radial nerve in the radial groove (mid shaft of the humerus) Symptom: Inability to extend the wrist and fingers Metacarpophalangeal, PIP and DIP joints Wrist remains partly flexed due to unopposed flexor activity Radial Nerve Palsy: https://3d4medic.al/aQLhmLZQ Wrist drop: https://3d4medic.al/Zaz8GdYb Click Fractures of the to edit Master Radius: title style Distal “Colles Fracture” Name Colles Fracture Mechanism of Extension Fracture Injury Falling on an outstretched hand i.e., Forced dorsiflexion of the wrist while the forearm and hand are pronated (e.g., when breaking a fall) Presentation “Dinner Fork Deformity” Complete transverse fracture of distal radius Distal radial fragment is displaced dorsally Ulnar styloid process may be avulsed Associated o Acute carpal tunnel syndrome o Compressive neuropathy Injuries o Ischemia Click Fractures of the to edit Master Radius: title style Distal “Smith’s Fracture” Name Smith’s Fracture (less common than Colles) Mechanism of Reverse Colles Fracture- Flexion Fracture Injury Falling onto flexed wrist Impact on dorsum of hand Presentation Complete transverse fracture of distal radius Distal radial fragment is displaced ventrally Ulnar styloid process may be avulsed Associated o Acute carpal tunnel syndrome o Compressive neuropathy Injuries https://3d4medic.al/5Ptq1dtH o Ischemia Click Movements to edit MasterCreated by Each Nerve title style Click Common Carpal to edit Master title Fractures style Name Scaphoid Fracture Hamate Fracture Mechanism of Injury Falling on an outstretched hand Repeatedly gripping a bat or club placing pressure on the hook of hamate Presentation Most common carpal fractured A hamate fracture can compress the ulnar Patients present with pain & tenderness in nerve, leading to: the anatomical snuff box loss of sensation in the medial half of Avascular necrosis is a common complication digit 4 & whole digit 5 – damage to the palmar (20%) & dorsal (80%) As ulnar nerve runs through a canal (Guyon’s carpal branches of the radial artery Canal) under the ligament between hamate & pisiform bone. Impingement here leads to Guyon’s Canal Syndrome Scaphoid Avascular Necrosis: https://3d4medic.al/1FqiIC3C Guyon’s Canal Syndrome: https://3d4medic.al/hCIrEbTj Click Repetitive Stress to edit Master titleInjuries style of the Elbow Lateral Epicondylitis Medial Epicondylitis “Tennis Elbow” “Golfer’s Elbow” Common extensor origin site Common flexor origin site https://3d4medic.al/2nWQSpey https://3d4medic.al/7P55SwXV Click Swan to editNeck Deformity Master title style vs. Boutonniere Deformity Name Swan Neck Deformity Boutonniere Deformity Presentation Hyperextension of the proximal interphalangeal Flexion of the proximal interphalangeal (PIP) (PIP) joints joints Flexion of the distal interphalangeal (DIP) joints Hyperextension of the distal interphalangeal (DIP) joints Image  Mallet Click to Fingertitle edit Master vs. style Swan Neck Deformity vs. Boutonniere Deformity Mallet Finger Boutonniere Deformity Swan Neck Deformity Click Heberden’s to edit Master&title Bouchard’s style Nodes Name Heberden’s Node Bouchard’s nodes Mechanism of Injury Hand Osteoarthritis Presentation Bony enlargement at the distal interphalangeal Bony enlargement at the proximal joint (DIP) interphalangeal joint (PIP) Thank you for your attention and participation