Upper Limb 2.pdf

MED 2160 Upper Limb 2 Upper Limb 2 – Arm, Forearm, and Hand Learning Objectives: 1. Understand anatomical terms related to joint movements of the elbow, wrist, and hand. 2. Relate comp...

MED 2160 Upper Limb 2 Upper Limb 2 – Arm, Forearm, and Hand Learning Objectives: 1. Understand anatomical terms related to joint movements of the elbow, wrist, and hand. 2. Relate compartments to common muscle actions, attachments, and innervations. 3. Understand the general organization of the intrinsic muscles of the hand. 4. Connect muscle attachments to muscle actions and appreciate skeletal lever systems. Movement Terminology Movements/Actions F Flexion / Extension - Abduction / Adduction E F ↓ Supination / Pronation # wrist Angers Radial / Ulnar Deviation E elbow vina- -radius Radial parallel " Deviation G radius & crossesna over vra tion I bones 1 Forearm I rotating along for PIP E Chand ridel Il the proxima pd 5 distal I 2 interrangeal Abduction 413 Supination Pronation Adduction > - holding a bowl of sorp Extension Flexion Adduction Abduction Opposition 1  MED 2160 Upper Limb 2 Compartments of the Arm Anterior Action: Flexion (elbow and shoulder) Innervation: Musculocutaneous nerve biceps Origin: Insertion: Humerus and scapula Radius and ulna “Coracobrachialis m.” *Biceps brachii are strong supinators of the forearm Posterior Action: Extension (elbow and shoulder) Innervation: Radial nerve triceps Origin: Insertion: Humerus and scapula Ulna Posterior View Anterior view *Axillary nerve - deltoid m. - teres minor m. Cross-section of the Arm Antenor P Transverse Humerus crosnon Posterior 2 MED 2160 Upper Limb 2 Compartments of the Forearm Anterior Action: Flexion (wrist and digits), pronation Innervation: Median (primarily) and ulnar nerves Origin: Medial epicondyle of the humerus “Flexor carpi radialis m.” Insertion: Carpals and digits Posterior Action: Extension (wrist and digits), supination Innervation: Radial nerve Origin: Lateral epicondyle of the humerus Insertion: Carpals and digits *The brachioradialis m. produces elbow flexion and attaches to the humerus Posterior View Anterior view eplateraMedie Cross-section of the Forearm D L R U 3 MED 2160 Upper Limb 2 Muscles of the Hand Intrinsic Muscles Action: Abduct/adduct digits, fine digit control - Innervation: Median and Ulnar nerves Thenar – Fine control of digit 1 (thumb) Hypothenar – Fine control of digit 5 Dinky Lumbricals – Flex MCP joints, extend IP joints "yumbricals" Interossei – Abduct and adduct digits a sandwich holding Angers ↑ Anterior view pahm Cross-section of the Hand Palmar I G Dorsal M & 4  MED 2160 Upper Limb 2 Limb Function: Muscle Attachment Points and Leverage Anterior View : Right Forearm contraction = muscle pronator ↓ quadratus ↓ this of supinato S inator Radius Vina & - contraction of these muscles = pronation ↑ pronator teres First Class Levers - very efficient Need same load on both # sides to balance ↳ Fulcrum very Third Class Levers biceps strong - really inefficient ↓ ↓ M why ? ↓ # Range - harder to build muscle W ↑ of - compact design Motion Fulcrum trade off / - : better velocity 5 - excursion out of joint for lower efficiency MED 2160 Upper Limb Lab II Upper Limb Lab II (Arm, Forearm, and Hand) Learning Objectives: Upon completion of the first upper limb lab session, you will be able to: (1) Describe and compare the features of the bones of the arm, forearm, and hand. (2) Describe and compare the basic functions, innervations, supply, and relationships of the muscles of the arm, forearm, and hand. Overview: This document contains background information for the second Upper Limb lab. This information is an abridged version of the relevant sections of Essential Clinical Anatomy 5th Edition, Chapters 6. Please read this document before your lab session. Only typical examples of the structures discussed in this handout will be pinned on the Gateways cadavers as part of the lab group assignment. Additional questions will be based on the information in this handout. This lab is meant to introduce you to 1) the surface anatomy, 2) osteology, 3) fascial layers, 4) muscles, and 5) neurovascular supply to the arm, forearm, and hand. Paper copies of this handout also will be available in the lab for your reference. Additional preparation may include any of the following additional resources. Additional Resources: Visible Body app: o Regional Views – Thorax, Cubital Fossa Highlight and read about the relevant bones, muscles, nerves and vessels of the forearm and hand. o Gross Anatomy Lab – Upper Limb o System Views – Skeletal, Muscular, Circulatory, Nervous Center on the upper extremity and read about the systems. o Muscle actions animations – NOTE that you can rotate the animation while it is playing View flexion, extension, abduction, adduction, and forearm pronation and supination. o Quizzes Try to identify the structures in the upper extremity quiz module. Essentials of Clinical Anatomy: o Chapter 6 – Upper Limb Lectures: Upper Limb 2 1 MED 2160 Upper Limb Lab II SURFACE ANATOMY The Brachium (Arm) The humerus is the largest bone of the upper extremity On the dorsal surface of the wrist, the styloid process of the radius can be palpated laterally in the anatomical snuff box, a triangular depression that can be raised by abducting and extending the thumb. Because the radial styloid process is larger and approximately 1 cm more distal than the ulnar styloid process, the wrist has less range of radial deviation than ulnar deviation. The dorsal tubercle of radius is easily felt around the middle of the dorsal aspect of the distal end of the radius. The head of the ulna forms a rounded subcutaneous prominence that can be easily seen and palpated on the medial side of the dorsal aspect of the wrist. The pointed subcutaneous ulnar styloid process may be felt slightly distal to the ulnar head when the hand is supinated. The pisiform can be felt on the anterior aspect of the medial border of the wrist and can be moved from side to side when the hand is relaxed. The hook of the hamate can be palpated on deep pressure over the medial side of the palm, about 2 cm distal and lateral to the pisiform. The tubercles of the scaphoid and trapezium can be palpated at the base and medial aspect of the thenar eminence (ball of thumb) when the hand is extended. The metacarpals, although overlain by the long extensor tendons of the digits, can be palpated on the dorsum of the hand. The heads of the metacarpals form the knuckles; the 3rd metacarpal head is the most prominent. The dorsal aspects of the phalanges can be palpated easily. The knuckles of the fingers are formed by the heads of the proximal and middle phalanges. 2 MED 2160 Upper Limb Lab II OSTEOLOGY The Brachium (Arm) The humerus is the largest bone of the upper extremity and the main bone of the arm. The humerus has the following features: Head - the large, rounded end that articulates with the glenoid fossa of the scapula. Anatomical neck - constriction just inferior to the head where the glenohumeral joint capsule and rotator cuff tendons attach. Greater and lesser tubercles - sites of muscle attachment just inferior to the anatomical neck. Intertubercular groove - groove between the tubercles for the tendon of the long head of the biceps brachii muscle. Surgical neck - small, depressed ring around the humerus just inferior to the tubercles. Deltoid tuberosity - site for the attachment of the deltoid muscle laterally. Medial and Lateral epicondyles – sites of attachment for digit/wrist extensors and flexors. The Antebrachium (Forearm) The radius and ulna are the paired bones that form the skeleton of the forearm. The primary articulation at the elbow is between the humerus and the ulna, whereas the primary articulation at the wrist is between the radius and the proximal carpal bones, with no involvement of the distal ulna. The radius and ulna also articulate with one another, which allows pronation and supination of the forearm. The radius and ulna are joined to each other along their lengths by a strong interosseus membrane. The ulna has the following features: Trochlear notch - articulates with the trochlea of the humerus at the humeroulnar joint. Olecranon process - posterior projection that is the attachment site for the triceps brachii muscle. It increases the leverage of this muscle. Coronoid process - raised feature for the insertion of the brachialis muscle. Styloid process - distal medial projection at the wrist. The radius has the following features: 3 MED 2160 Upper Limb Lab II Head - shallow, bowl-like depression for articulation with the capitulum of the humerus. Radial tuberosity - site of insertion of the biceps brachii tendon. Styloid process - distal lateral projection that articulates with the carpus at the radiocarpal joint. Dorsal tubercle - distal dorsal Anterior bump around which the tendon view of the extensor pollicis longus wraps on its way to the 1st digit. The Hand The hand contains 27 bones. There are eight carpal bones that form the wrist, arranged in proximal and distal rows. Collectively, the carpal bones form a U- shaped passage, the carpal tunnel, that is roofed over by ligaments. This is a tight space through which nine forearm flexor muscle tendons and the median nerve pass to the palm of the hand. There are five metacarpal bones that articulate with the proximal phalanges at the metacarpophalangeal (MCP) joints, or knuckles. The distal heads of metacarpals 2-5 are tightly bound together by ligaments, whereas metacarpal 1 is untethered in the palm and quite mobile. Rotation of the first metacarpal permits opposition of the thumb. There five digits in the hand. Digit number 1 is the pollex (thumb) and digit number 5 is the pinky. The pollex is composed of two phalanges, while digits 2-5 are made up of three phalanges each. The joints between the phalanges are interphalangeal (IP) joints. Digits 2-5 have proximal and distal IP joints, whereas the pollex has a single IP joint. 4 MED 2160 Upper Limb Lab II FASCIAL LAYERS Connective tissue can form thin, tough fibrous fascial layers that surround muscles and divide regions of the body. The pectoral fascia invests the pectoralis major. Laterally, it becomes the axillary fascia, which forms the floor of the axilla. The scapulohumeral muscles that cover the scapula and form the bulk of the shoulder are also ensheathed by deep fascial layers that are continuous with one another. The tough fascial layers of the shoulder and axilla are continuous inferiorly with the brachial fascia, a sheath of deep fascia that encloses the arm like a snug sleeve. The brachial fascia is continuous inferiorly with the antebrachial fascia, which in turn encloses the forearm like a snug sleeve. The arm proper is divided into anterior and posterior compartments by sheet-like projections of the brachial fascia that attach to the humerus. The forearm is divided into anterior and posterior compartments by a sheet-like projection of the antebrachial fascia that attaches to the radius and the interosseous membrane that stretches between the radius and ulna. The antebrachial fascia thickens inferiorly to form anterior and posterior retinacula, thickened transverse bands that hold the forearm tendons in place as they cross the wrist into the hand. The compartments formed by these fascial layers are developmentally and functionally separate and are innervated by specific parts of the brachial plexus. The antebrachial fascia continues beyond the extensor and flexor retinacula of the wrist as the palmar fascia in the palm of the hand. The central part of the palmar fascia, the palmar aponeurosis, is thick, tendinous, and triangular. Strong skin ligaments extend from the palmar aponeurosis to the skin, holding the palmar skin close to the aponeurosis so that the skin of the palm does not slip while gripping objects. 5 MED 2160 Upper Limb Lab II MUSCLES Anterior Arm There are three muscles in the anterior compartment of the arm that flex the elbow and shoulder. The biceps brachii is the most superficial. The short head of the biceps is the more medial and attaches to the coracoid process of the scapula. The long head is the more lateral and appears shorter, because the tendon of the long head disappears as it passes through the glenohumeral joint capsule via the intertubercular groove to attach to the supraglenoid tubercle of the scapula. The two heads of the biceps come together and insert by a single distal tendon onto the radius and the superficial fascia of the forearm by the bicipital aponeurosis. Because this muscle crosses the shoulder, it can aid in flexing the glenohumeral joint. However, its main function is as a powerful flexor of the elbow. The coracobrachialis is an elongated muscle in the superomedial part of the arm. It attaches proximally to the coracoid process of the scapula and distally to the middle third of the humerus. This muscle’s sole function is flexion of the glenohumeral joint. The brachialis is a flattened fusiform muscle that lies deep to the biceps brachii. It is the workhorse of elbow flexion, flexing the elbow in all positions, and during slow and quick movements. It attaches to the humerus just inferior to the coracobrachialis muscle, crosses the elbow joint, and inserts into the ulna. Posterior Arm The triceps brachii is the only muscle in the posterior compartment of the arm but symmetry with the anterior compartment is imparted by its three heads. The two superficial heads are the lateral head, which attaches to the posterior surface of the humerus, and the long head, which attaches to the scapula. The medial head is deep to these, also attaching to the posterior surface of the humerus inferior to the lateral head. The triceps brachii extends the elbow and its long head also aids in extending the shoulder. 6 MED 2160 Upper Limb Lab II Anterior Forearm Most of the anterior muscles of the forearm originate from the medial epicondyle of the humerus and technically cross the elbow joint, but they have only a trivial effect on elbow flexion. The muscles are arranged in superficial, intermediate and deep layers. Anterior view The superficial muscles include from lateral to medial: pronator teres, flexor carpi radialis, palmaris longus, and flexor carpi ulnaris. Pronator teres crosses the forearm at an angle and inserts onto the radius, causing pronation of the forearm (rotates the forearm so that the wrist faces posteriorly). The flexor carpi radialis and flexor carpi ulnaris muscles attach to the radial and ulnar sides of the wrist, respectively. In addition to flexing the wrist, these muscles contribute to abduction and adduction (radial and ulnar deviation), respectively. If present, palmaris longus extends into the palm and contributes to flexion of the wrist and tension of the palmar aponeurosis. Just deep to the superficial muscles is the flexor digitorum superficialis, a broad muscle with four tendons that pass through carpal tunnel and palm to insert onto the middle phalanges of digits 2- 5. This muscle flexes digits 2-5 and also the wrist by passing anterior to it. More deeply, there are three additional muscles: flexor pollicis longus, flexor digitorum profundus and pronator quadratus. The tendons of flexor pollicis longus and flexor digitorum profundus pass through the carpal tunnel to insert onto the distal phalanges of all five digits. These muscles flex the digits and also the wrist by passing anterior to it. The pronator quadratus is a small deep muscle that passes transversely between the ulna and radius. This muscle is the prime mover in pronation of the forearm. 7 MED 2160 Upper Limb Lab II Posterior Forearm Most of the posterior muscles of the forearm originate from the lateral epicondyle of the humerus and technically cross the elbow joint, but they have only a trivial effect on elbow extension. The muscles are arranged in superficial and deep layers. The superficial muscles include from lateral to medial: brachioradialis, extensor carpi radialis longus and brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris and anconeus. Brachioradialis ends at the distal radius and is a “flexor wannabe”. It flexes the elbow when the hand is held in a neutral position with the thumb pointing anteriorly. The extensor carpi radialis (longus and brevis) and extensor carpi ulnaris muscles attach to the radial and ulnar sides of the wrist, respectively. In addition to extending the wrist, these muscles contribute to abduction and adduction (radial and ulnar deviation), respectively. The extensor digitorum and extensor digiti minimi muscles insert on the intermediate and distal phalanges of digits 2-5 and extend the digits, as well as the wrist by passing posterior to it. Extensor digiti minimi confers independent extension to the pinky finger. The anconeus is a small triangular muscle that is said to assist in extending the elbow, but given its size that contribution must be minor. Deep to the superficial muscles are the following from proximal to distal: supinator, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, and extensor indicis. The supinator muscle extends inferiorly to the proximal third of the radius and supinates the forearm (rotates the forearm so that the wrist faces anteriorly), assisting the more powerful biceps brachii. The abductor pollicis longus, extensor pollicis brevis and extensor pollicis longus muscles insert on the thumb and their names indicate their actions on the thumb. The tendon of the extensor pollicis longus hooks around the dorsal tubercle of the radius, leaving a noticeable gap, called the anatomical snuff box, between it and the extensor pollicis brevis tendon on the dorsal surface of the hand. The anatomical snuff box becomes visible when the thumb is abducted and extended. The extensor indicis inserts on the second digit and assists extensor digitorum in extending it. Extensor indicis confers independent extension to the index finger. Because all four of these deep distal muscles cross the wrist joint, they also aid in extending the wrist. Intrinsic hand muscles The intrinsic muscles of the hand are located in the palm and form five functional groups: 8 MED 2160 Upper Limb Lab II 1. Thenar muscles – a lateral eminence over the first Palmar view metacarpal made up of three muscles (flexor pollicis brevis, opponens pollicis and abductor pollicis brevis), chiefly responsible for opposition and precise movements of the thumb. 2. Hypothenar muscles – a medial eminence over the 5th metacarpal made up of three muscles (flexor digiti minimi brevis, opponens digiti minimi and abductor digiti minimi), chiefly responsible for precise movements of the pinky. 3. Adductor pollicis – deeply positioned adductor of the thumb. 4. Lumbricals – four slender muscles that originate from the tendons of the flexor digitorum profundus. These muscles cause flexion at the metacarpophalangeal joints and simultaneous extension at the interphalangeal joints of digits 2-5. 5. Interossei – two sets of dorsally and palmarly positioned muscles that originate from between the metacarpals and attach to the digits laterally. These muscles cause abduction and adduction of digits 2, 4 and 5. Because the first metacarpal is not tethered to the others, the first dorsal interosseus muscle is quite large and distinctive. NERVES AND VESSELS Hand At the wrist, the ulnar artery and nerve enter the hand through the ulnar canal (Guyon’s canal) formed by parts of two of the carpal bones. The ulnar canal is superficial to the carpal tunnel and less well protected. In the palm, the ulnar artery is the main contributor of blood to the superficial palmar arch, which gives rise to common pal mar and proper palmar digital arteries that supply the lateral aspects of the digits. The radial artery curves onto the dorsum of the hand through the anatomical snuff box and enters the palm by passing between the heads of the large first dorsal interosseous muscle. It then turns medially to form the deep palmar arch, which lies across the metacarpals just 9 MED 2160 Upper Limb Lab II distal to their bases. There are many anastomoses between the superficial and deep palmar arches. In the hand, the median nerve supplies the thenar muscles and the first and second lumbricals. The ulnar nerve supplies all of the intrinsic hand muscles except those supplied by the median nerve. Sensation from the skin of the lateral palm and the palmar surfaces of the first three digits is carried in the median nerve. Sensation from the skin of the lateral dorsum of the hand and the dorsal surfaces of the first three digits is carried in the radial nerve. Sensation from the medial part of the hand and digits 4-5 is carried in the ulnar nerve. Forearm Three of the five terminal branches of the brachial plexus pass through the forearm: the radial, ulnar and median nerves. The first two travel with branches of the brachial artery, which splits near the elbow to form the radial and ulnar arteries. Note that veins with the same names accompany the arteries. The radial artery and superficial radial nerve travel inferiorly on the radial side of the forearm just deep to the brachioradialis muscle. The superficial radial nerve is one of two branches of the radial nerve, which splits near the origin of the brachioradialis muscle on its deep Anterior view surface. The superficial branch of the radial nerve is sensory, whereas the deep branch of the radial nerve travels into the posterior compartment of the forearm to innervate the muscles there. Close to the wrist, the radial artery and superficial radial nerve become superficial and pass onto the posterior surface of the hand through the anatomical snuff box. The ulnar artery gives off a large branch, the common interosseous artery, which immediately splits to form the anterior and posterior interosseous arteries. These pass anterior and posterior to the interosseous membrane deep 10 MED 2160 Upper Limb Lab II within the forearm. The posterior interosseus artery is the main source of blood to the posterior compartment of the forearm. The main trunk of the ulnar artery continues inferiorly on the medial side of the forearm with the ulnar nerve, which enters the anterior forearm after passing posterior to the medial epicondyle of the humerus. The ulnar nerve and artery lie deep to the flexor carpi ulnaris muscle. In the anterior forearm, the ulnar nerve supplies the flexor carpi ulnaris and the medial half of the flexor digitorum profundus. The ulnar nerve and artery become superficial at the wrist. The median nerve enters the anterior forearm with the brachial artery and passes distally between the superficial and deep digital flexors. It is the only nerve to travel through the forearm without accompanying blood vessels. It supplies all of the muscles of the anterior forearm except for those supplied by the ulnar nerve. At the wrist, the median nerve enters the hand through the carpal tunnel, along with the eight tendons of the flexor digitorum superficialis and profundus muscles and the tendon of the flexor pollicis longus. The carpal tunnel is formed by the carpal bones held into a U-shaped configuration by a very strong anterior ligament called the flexor retinaculum. PRONATION AND SUPINATION Pronation of the forearm involves rotating the distal end of the radius across the ulna. This rotation occurs at the humeroradial joint and the proximal and distal radioulnar joints, and is permitted by the flexibility imparted by the interosseus membrane. Pronation is the weaker movement involving shortening of the pronator teres and pronator quadratus muscles. The supinator and biceps brachii muscles must relax and become wrapped around the radius. Supination is the stronger movement (think “righty tighty” in right-handed people) in which the pronators relax and the biceps and supinator muscles forcefully unroll. Supination is strongest when the forearm is flexed, allowing the full power of the biceps brachii muscle to be employed. 11  Humerus: & Identify the following structures on the vertebra. Using the following pages, identify which muscles, if any, originate or insert onto each of the structures. Structures:  Head  Bicipital (Intertubercular) Groove  Medial Epicondyle  Anatomical Neck  Spiral (Radial) Groove  Lateral Epicondyles  Surgical Neck  Deltoid Tuberosity  Supracondylar Ridge  Greater Tubercle  Trochlea  Capitulum  Lesser Tubercle  Olecranon Fossa  Coronoid Fossa Head Humerous ball is superior Right creater↓ - and medial Tubercle Most lateral paintoterus ↓ lesser tubercle Bicipital groove Deltoid tuberosity lateral epicondule & Medial epicondyle > - supracondyl ridges ar X Hinge jointz capitulum ↳ Trochlea ↳ where radial head inserts on to coronold fossa Anterior posterior veiw as Anatomic > - I wrap hand around head) - Surgical Neck spiral grooveposterior side diagonal olecranon fussa  Lab 4 Lab Prep Activity Below is an anterior view of the hand. Using the following page, identify and label the insertions of Flexor Carpi Ulnaris, Flexor Carpi Radialis, Flexor Digitorum Superficialis, Flexor Pollicis Longus, and Flexor Digitorum Profundus. Insertion for So insertion for flexor digitorum t flexor digitorum superficial is profundus for insertion S DIP policlongos flexor ↑ PIP MCP insertion of flexor > - carpi ulnaris - insertion of flexor carpi radial is Lab 4: Antebrachium Flexors  Pronator Teres Humeral head : medial epicondyle of numerus Origin : Ulnar Head : coranoid process of ulna Insertion : middle of lateral radius Action : pronation of forearm w/ contraction Innervation : median nerve Anterior forearm  Flexor Carpi Ulnaris medial epicondyle Humeral head : of humerus Vinar Head : process Origin : olecranon S and proximal posterior Ulna hook of namate, Insertion : pisiform , base of 5th metacarpal Action : flexionof wrist , ulnar deviation of wrist Innervation : Unar nerve Anterior Forearm  Palmaris Longus of humerus :Medial epicondyle Origin Insertion : palmar aponeurosis , flexor refinacuum , bases of proximal phalanges Action : Flexion of wrist Innervation : medial nerve Anterior Forearm  Flexor Carpi Radialis Medial epicondyle of humerus Origin : Insertion : base of 2nd/3rd metacarpals Action : flexion of wrist , radial deviation of wrist Innervation : Median Nerve Anterior forearm  Flexor Digitorum Superficialis medial epicondyle of humerus, Origin : of ulna proximal anteriou coranoid process , surface of radius of 2-5 Insertion : Middle phalanges digits Action : flexion of wrist Innervation : median nerve Anterior Forearm  Pronator Quadratus Origin distal : anteromedial ulna Insertion : distal anterolateral radius Action : pronation of forearm Innervation : Median nerve Anterior forearm  Flexor Pollicis Longus anterior surface of radius , Origin : interossers membrane Insertion : base of distal phalanx of digit I Action : flexion of thumb at IP joint Innervation : Median nerve Anterior Forearm  Flexor Digitorum Profundus surface of ulna Origin : proximal Insertion : base of distal phalanges 2 - 5 Action : flexion of wrist , flexion of digits DIP joints 2-5 at MCP PIP , and, 2-3 Median N. Innervation : digits : 4-3 Unar N. digits : Anterior Forearm Extensors  Extensor Carpi Radialis Longus : lateral supercondylar ridge Origin , lateral epicondyle on humerus Insertion : base of 2nd metacarpal Action : extension of wrist , radial deviation of Wrist Innervation : Radial N. Posterior Forearm  Extensor Carpi Radialis Brevis of homers Origin epicondyle : lateral Insertion : base of 3rd metacarpal Action : extension of wrist branch of radial N. Innervation : deep Posterior Forearm  Extensor Digitorum Origin : lateral epicondyle of humerus Insertion : extensor expansion of digits 2 5- Action : extension of wrist , extension -S at MCP joints of digits Innervation : deep branch of radial nerve posterior forearm  Extensor Digiti Minimi of lateral epicondyle Origin : humerus Insertion : extensor expansion digits Wrist , extension Action : extension of 5 at MCP joint digit. N Innervation : deep branch radial posterior forearm  Extensor Carpi Ulnaris Humeral head :lateral epicondyle of Origin : numerus ulnar head : proximal posterior Una Insertion : base of 5th metacarpal - Action : extension of wrist , ulnar deviation of wrist Innervation : deep branch radial N. posterior forearm  Supinator of humerus , lateral epicondyle Origin : - radial collateral ligaments, annular and crest of ulna supinator surface of proximal Insertion : lateral - radius of arm Action : supination deep branch of radial N Innervation :. posterior forearm  Extensor Indicis posterior ulna , adjacent Origininterosseous : membrane Insertion : extensor expansion of digit 2 Action : extension of Wrist , extension of digit 2 at MCP joint Innervation : deep branch of radial N. Posterior forearm  Abductor Pollicis Longus , is Origin :posteriorsurfacesofradiusln Insertion : base of 1st metacarpal of wrist , abduction Action : radial deviation of thumb at CMC joint Innervation : deep branch of radial N. posterior forearm  Extensor Pollicis Brevis posterior radius , interosseous Origin : membrane Insertion : base of proximal phalanx of - digit Action : deviation of Wrist radial , extension of thumb at McP joint Innervation : deep branch of radial N. posterior forearm  Extensor Pollicis Longus middle posterior ulna and Origin : interosseous membrane Insertion : base of distal phalanx of - digit I Action radial deviation of wrist : , at CMC extension of thumb joint Innervation : deep branch of radial N. posterior forearm  Lab 4 Antebrachium  The Antebrachium: Radius and Ulna Proximal radio-ulnar joint: Elbow Ulna Radius Distal radio-ulnar joint: Wrist  The Radius Head Neck Radial Tuberosity Anterior View Styloid Process Distal Radius Styloid Process Ulnar Notch  Proximal Ulna Coronoid Process Olecranon Process  Proximal Ulna Trochlear Notch Radial Notch Distal Ulna Head Styloid Process  Olecranon Process (anteriorly-facing) Head Trochlear Notch Neck Coronoid Process Radial Tuberosity (anteriorly-facing) Proximal Radioulnar Joint (Head of Radius + Radial Notch of Ulna) Distal Radioulnar Joint (Head of Ulna + Shafts Ulnar Notch of Radius) Head Styloid Process Styloid Process (posteriorly-facing)  Lab 4 Diagrams: Label the following drawing. Fill out the corresponding questions/tables on TopHat to supplement the diagrams. Cubital Fossa: Elbow pit Brachialis floor L muscle tan) floors are the muscles Ideep that all of the Vessels ↓ Brachii Biceps < on top of pass Radial line between lateral/ Supinator Nerve medial epicondyle (floor) pronator t teres superncial branch of Radial Nerve Deep branch Nerve of radial nerve Median Biceps Brachial Tendon Artery F Medial border lateral border ↓ ulnar Brachioradial is Artery Radial pronator Artery teres is muscle border Lateral Medial scapula coracoid - > Retweet - - vina coranoid Radius Lab 4 Osteology - Thumb Label the following drawings. *Make sure you know which muscles, if any, originate/insert on these structures* Radius: Identify the following structures on the vertebra. Using the following pages, identify which muscles, if any, originate or insert onto each of the structures. Structures:  Head  Interosseous Border  Radial Tuberosity  Neck  Ulnar Notch  Styloid Process  Dorsal Tubercle Radius j Proximal Lallous for Radial Promotion I Head supination) radial Neck - Radial Tuberosity Canterior/towards I I vlnar side a ka pinky) Interossers Interosseus border border - Dorsal Tubercle Distal vinar notch > - ge > Radial Styloid process - Ulna: Identify the following structures on the vertebra. Using the following pages, identify which muscles, if any, originate or insert onto each of the structures. Structures:  Olecranon Process  Trochlear Notch  Interosseous Border  Coronoid Process  Ulnar Tuberosity  Head  Styloid Process  end Anterior proximal ( Posterior llooks like a wrench > - Olecranon > - Inside of hook = process - Trocnlear fits into the radial anterior olecranon fossa Notch I and distal projection posterior ↓ coronoid humerus in extension process vinar tuberosity Interosseus border vinar head vinar styloid process * heads fit into the notches extension flexion coranoid process empty coranoid fossa holding coranoid process Right arm vina Radius O vinar ruberosity j Interosseus - borders  ↓ Snuff box  flex Brachium – fascia Two septae: medial and lateral Separate into anterior and posterior compartments of the arm extend Functionally separate elbow flexors and extensors 29  Biceps brachii—Anterior compartment of the muscle head > 3 long - on * works forearm separate bicipital Biceps is a prime groove joints flexor of the elbow long head Short head also ↓ flexes the shoulder T  origin on the Short coracoid process head Inserts on radial Nerve : tuberosity and supply supinates radius short head- coracoid process musculnerve ocutaneous origin : long head-supraglenoid tubercle Action : both heads - supination of Action : forearm , flexion of elbow30 Short head-flexion shoulder  * elbow extensors * only head that has the Triceps (posterior) capacity to work on the is the long shoulder joint head we its Main action is at the elbow insertion but also stabilizes the Onto the humerus in the GH joint scapula Long head aids in extension of the shoulder, all heads all 3 heads * extend elbow are located in Origin long head-infraglenoid : tubercle the brachium lateral head" posterior humerus above spinalgroove Action : both heads medial head-posterior humerus extension of elbow below spinal groove long head- extension shoulder Insertion : Olecranon process 31 Nerve : RADIAL  Brachioradialis (anterior) O: lateral supracondylar just proximal ridge of the humerus to the lateral I: styloid process of the epicondyle radius A: Elbow flexor with forearm in neutral, especially with resistance N: radial (as a lateral forearm muscle, the bulk of this muscle is anterior, but its innervation is posterior) 21 Antebrachial muscles Superficial anterior forearm brachioradialis Radial nerve pronator teres Median nerve flexor carpi radialis Median nerve palmaris longus Median nerve flexor carpi ulnaris Ulnar nerve 34  Antebrachial muscles Intermediate anterior forearm flexor digitorum superficialis Median nerve 35  Antebrachial muscles Deep anterior forearm flexor digitorum profundus Median (digits 2-3) and ulnar (digits 4-5) flexor pollicis longus Pronator Median nerve quadratus Median nerve 36 Antebrachial muscles Superficial posterior forearm ext. carpi radialis longus Radial nerve ext. carpi radialis brevis Deep branch of radial nerve ext. digitorum Deep branch of radial nerve ext. digiti minimi Deep branch of radial nerve ext. carpi ulnaris Deep branch of radial nerve 38  Antebrachial muscles Deep posterior forearm supinator Deep branch of radial nerve abductor pollicis longus Deep branch of radial nerve extensor pollicis brevis Deep branch of radial nerve extensor pollicis longus Deep branch of radial nerve extensor indicis Deep branch of radial nerve 39  anterior arm coracobrachialis - O : coracoid process I : middle of medial numerus A : flexion of shoulder adduction of shoulder , N : musculocutaneous nerve Lumbricals (hands) O : flexor digitorum profundus tendons 1 radial side of extensor expansion 2-5 : digits A: flexion of digits 2-5 at MCP joints , extension of digits 2-5 at PIP and DIP joints N 2-3 medial nerve : digits : Unar nerve digits 4-5 : Palmar Interossei 0 : Palmar surfaces of 2, 4 , 5 metacarpals and extensor 1 bases of proximal phalanges expansions of digits 2, 4 5 , ulnar. side of digit 2 , radial side of digit 41S A: adduction/flexion of digits , 4. 5 2 at MCP joints , extension of digits 2 , 4 , 5 at PIP and DIP joints N : Ulnar N.  Lab 5 Diagrams Diagrams: Please watch the videos on TopHat and label the following drawings. Dorsal Hood Diagram: DIP PIP ↑ MCP - DIP ↑ A Finger ( - PIP / on Orientat I PIP DIP - MCP - MCP - CMC - CMC - CMC only Intrinsic extensor Muscle activation only Intrinsic digitorum + activation ED D) / PIP = Distal/Proximal Interphalangeal Joint MCP = Metacarpalphalangeal Joint CMC Blood Supply: Carpometacarpal Joint = superfici al orsal branch of D carpal branch radialutery of radial artery superficial branch of Vinar Artery Hypothenar - eminance ↓ The nar Deep branch eminance of Vinar Deep branch Dorsal carpal Artery of radial branch of ulnar artery Artery Dorsal Flexor Carpal Branch extensor of Ulnar Retinaculum retinaculum Artery  Nerve Supply: Vinar Nerve Median Nerve Canyon of Guyon Dorsal Cutaneous branch of ulnar Dorsal Dorsal Nerve cutaneous cutaneous Dorsal cutaneous Vinar branch of Median Nerve Nerve radia Nerve Anatomical Snuff Box & Carpal Bones: Extensor Pollicis longus Bones Extensor Pollicis Brevis HC T T Abductor Pollicis PTL S Longus Distal Thumb I Digit proximal Lab 5 Osteology Osteology: Label the following structures. *Make sure you know which muscles, if any, originate/insert on these structures* Hand: Identify the following structures on the hand. Using the following pages, identify which muscles, if any, originate or insert onto each of the structures. Structures:  Scaphoid  Pisiform  Hamate  Lunate  Trapezium  Metacarpals  Triquetrum  Trapezoid  Phalanges  Capitate ] carpal 7 Metacarpal phalanges /Lori Digit I Distal - - Middle p r ox i m a l DIP PIP joint joint J Phalanges Dista joint Digits 2-5 = 3 phalanges Proximal , middle , Distal  So the pinky here comes the thumb ---- long , - - -- trapezoid Scaphoid lunate Triquetrum pisiform hamate capitate trapezium Capitate - - -Hook Hamate of hamate 112 > - Pisiform lunate Triquetrum trapezium Schaphoid Trapezoid * proximal row * Distal row