Author: Read more. This muscle also modulates the movement of the deltoid like the other rotator cuff muscles. It acts to extend the wrist, fixes writs during clenching fist, and when it acts with flexor carpi ulnaris it contributes to ulnar deviation of the wrist. By looking at all of the upper limbs components separately we can appreciate and compartmentalize the information, then later view the upper limb as a whole and understand how all of its parts work in unison. Hypothenar eminence:It consists of the flexor digiti minimi brevis, the abductor digiti minimi brevis, and the opponens digiti minimi. 977 Cards -. 1. Muscles of the shoulder and upper limb can be divided into four groups: muscles that stabilize and position the pectoral girdle, muscles that move the arm, muscles that move the forearm, and muscles that move the wrists, hands, and fingers. Therefore, when they contract, the origin pulls the insertion and connected bone closer . Read more. The flexor pollicis brevis acts to flex the thumb at the 1st MP joint and is innervated by the median nerve. Extensor indicis proprius muscle:This muscle arises from the posterior distal 3rd of the ulna and interosseous membrane and inserts onto the middle and distal phalanx of the index finger. origin: in strips on the lateral and anterior surface of ribs the iliopsoas or inner hip muscles: Psoas major. Muscles involved in chewing must be able to exert enough pressure to bite through and then chew food before it is swallowed (Figure 11.4.4 and Table 11.4). psoas major - origin : lumbar vertebrae It can be difficult to learn the names and locations of the major muscles. Here's a mnemonic that summarizes the brachioradialis and helps you to remember it. You'll find this conveniently illustrated on the cheat sheets. The shoulder is most unstable in extension and external rotation. This muscle allows you to whistle, blow, and suck; and it contributes to the action of chewing. Triceps brachii muscle:This is the only muscle of the posterior compartment of the arm. The muscle has dual innervation. The sternocostal head arises from the sternum and the superior 6-7 costal cartilages. It lays directly superficial to the flexor digitorum superficialis. and grab your free ultimate anatomy study guide! Last reviewed: November 03, 2021 Tongue muscles can be extrinsic or intrinsic. This necrosis lead to a flattened thenar eminence (thumb mound palmar surface). It is innervated by the deep branch of the radial nerve. Extensor digiti minimi muscle:This muscle arises from the anterior surface of the lateral epicondyle of the humerus. Those in the same compartment will have the same action. Finally, the scalene muscles work together to flex, laterally flex, and rotate the head. The short head arises from the coracoid process and both heads unite. There are major muscles that you need to know, so without delay, lets give it a go. Both of these muscles are innervated by the anterior interosseous branch. Muscle: Extensor pollicis brevis. It also assists in medial (anterior fibers) and lateral rotation (posterior fibers). It inserts onto the radial aspect of the 1st metacarpal. Copyright View Origin and Insertion points as a layer map Origin and Insertion points are available as a layer of the Skeletal System, which show a map of all attachment points across the full skeleton. Let's take a look at an example. Skeletal Muscles (Comments, Origin, Insertion, Action, Nerve) by melissa1780d, Mar. Iliococcygeus is a thin sheet of muscle that traverses the pelvic canal from the tendinous arch of the levator ani to the midline iliococcygeal raphe where it joins with the muscle of the other side and connects with the superior surface of the sacrum and coccyx. Tearing most commonly occurs in the tendon of supraspinatus. Due to its course it has a "serrated" or "saw-toothed" appearance. Grounded on academic literature and research, validated by experts, and trusted by more than 2 million users. Upper limb muscles and movements: want to learn more about it? It most commonly dislocates anteriorly (95%), and can damage the axillary nerve. The particular movement is a direct result of the muscle attachment. Insertion: Proximal, medial tibia 3 in extensor compartment of arm: 3 heads of triceps (long, medial, lateral), 3 thenar muscles: abductor pollicis brevis, flexor pollicis brevis, opponens pollicis (+adductor pollicis), 3 hypothenar muscles: abductor digiti minimi, flexor digiti minimi, opponens digiti minmi (+palmaris brevis), 3 metacarpal muscles: dorsal interossei, palmar interossei, lumbricals, 3 abductors of digits: dorsal interossei, abductor pollicis brevis, abductor digiti minimi, Flexor carpi radialis muscle (cross-sectional view) -National Library of Medicine, Superficial head of flexor pollicis brevis muscle (ventral view) -Yousun Koh, Lumbrical muscles of the hand (ventral view) -Yousun Koh. Learning anatomy is a massive undertaking, and we're here to help you pass with flying colours. This also helps you understand its action (s) as well as what injuries may be present if there is pain in relevant areas. The origin is the attachment site that doesn't move during contraction, while the insertion is the attachment site that does move when the muscle contracts. The dorsal interossei cause abduction of the fingers and the palmar interossei cause adduction of the fingers. Click the card to flip . If the place is a bone that remains immobile for an action, the attachment is called an origin. Muscle origins and insertions Many muscles are attached to bones at either end via tendons. insertion: mediar aspect of humerus, Origin posterior border of iliac crest Place your finger on your eyebrows at the point of the bridge of the nose. The segmental muscles include the interspinales and intertransversarii. Try refreshing the page, or contact customer support. It is a powerful superficial muscle of the shoulder. The Cardiovascular System: The Heart, Chapter 20. I feel like its a lifeline. : imagine holding a suitcase or briefcase at your side. Supinator muscle:It is a small muscle that arises from the lateral epicondyle of the humerus, the supinator crest of the ulna, as well as the annular and radial collateral ligaments that support the radius against the ulna. The splenius muscles originate at the midline and run laterally and superiorly to their insertions. Register now The physicians originally studying human anatomy thought the skull looked like an apple. Manifestations are limited movement of the shoulder and severe pain. Chapter 1. It causes extension of the IP joints, the MP joints, and wrist. Some People Bang Like Monkeys. Although the tongue is obviously important for tasting food, it is also necessary for mastication, deglutition (swallowing), and speech (Figure 11.4.5 and Figure 11.4.6). The multifidus muscle of the lumbar region helps extend and laterally flex the vertebral column. Find it on your own body if you can. Fluid, Electrolyte, and Acid-Base Balance, Lindsay M. Biga, Sierra Dawson, Amy Harwell, Robin Hopkins, Joel Kaufmann, Mike LeMaster, Philip Matern, Katie Morrison-Graham, Devon Quick & Jon Runyeon, Next: 11.5 Axial muscles of the abdominal wall and thorax, Creative Commons Attribution-ShareAlike 4.0 International License, Moves eyes up and toward nose; rotates eyes from 1 oclock to 3 oclock, Common tendinous ring (ring attaches to optic foramen), Moves eyes down and toward nose; rotates eyes from 6 oclock to 3 oclock, Moves eyes up and away from nose; rotates eyeball from 12 oclock to 9 oclock, Surface of eyeball between inferior rectus and lateral rectus, Moves eyes down and away from nose; rotates eyeball from 6 oclock to 9 oclock, Suface of eyeball between superior rectus and lateral rectus, Maxilla arch; zygomatic arch (for masseter), Closes mouth; pulls lower jaw in under upper jaw, Superior (elevates); posterior (retracts), Opens mouth; pushes lower jaw out under upper jaw; moves lower jaw side-to-side, Inferior (depresses); posterior (protracts); lateral (abducts); medial (adducts), Closes mouth; pushes lower jaw out under upper jaw; moves lower jaw side-to-side, Superior (elevates); posterior (protracts); lateral (abducts); medial (adducts), Draws tongue to one side; depresses midline of tongue or protrudes tongue, Elevates root of tongue; closes oral cavity from pharynx. It also acts as an extensor of the wrist and radial deviator. EKG Rhythms | ECG Heart Rhythms Explained - Comprehensive NCLEX Review, Simple Anatomy Quiz Most Nurses Get WRONG! The scaphoid bone forms the floor of the anatomical snuffbox and articulates with the radius at the wrist. It inserts onto the medial border of the scapula just superior to the rhomboid major. We strive for 100% accuracy, but nursing procedures and state laws are constantly changing. The radial two lumbricals are innervated by the median nerve and the ulnar two are innervated by the ulnar nerve. Action: Extends thigh, flexes leg, Narrower than semimembranosus copyright 2003-2023 Study.com. Flexion, extension, abduction, adduction, rotation whether youre a doctor, physiotherapist or yoga teacher, knowing the functions of a given muscle is very important. There are two main ones, so lets break em in half. The pectoral girdle, or shoulder girdle, consists of the lateral ends of the clavicle and scapula, along . This website helped me pass! It is caused by damage to the extensor tendon complex as it inserts onto the distal phalanx of any of the digits. Learning anatomy is a massive undertaking, and we're here to help you pass with flying colours. This injury is commonly called baseball finger. This compartment is anterior in anatomical position. It arises from the nuchal ligament and spinous processes of C7 to T1. Working Scholars Bringing Tuition-Free College to the Community, Differentiate between origin and insertion, as well as proximal and distal, Explain how agonists, antagonists and synergists work together to control muscle movement. L: lateral two lumbricals. It consists mainly of type 1 muscle fibers and hence provides sustained elbow extension. This happens due to overuse, such as with a competitive swimmer or shotput thrower. flashcard sets. Agonists, or prime movers, are responsible for the bulk of the action. Get unlimited access to over 88,000 lessons. At the end of this video, you will be able to: 20 chapters | It causes flexion of the interphalangeal joint (IP joint) of the thumb, as well as flexion at the metacarpophalangeal joint (MP joint). The intrinsic muscles of the hand contain the origin and insertions within the carpal and metacarpal bones. Print Muscle Origin and Insertion: Definition and Actions Worksheet 1. 'Rule of 3s' and 'Busy BeesCollaBorate well'. Definition. There are relatively few muscles which its movements and function are easy to learn. It is innervated by the posterior interosseous branch. It runs down the posterior compartment of the forearm and inserts into the middle and distal phalanges of the 2nd to 5th digits. Register now Origin: Clavicle, acromion process, spine of scapula Insertion: Deltoid tuberosity of the humerus Action: Abducts arm; flexes, extends, medially, and laterally rotates arm. The opponens digiti minimi arises from the hook of hamate and flexor retinaculum. The distal phalanx therefore lies in permanent flexion, and has the appearance of a mallet. The erector spinae group forms the majority of the muscle mass of the back and it is the primary extensor of the vertebral column. (Superior part: Anterior surface of superior angle. The muscle inserts onto the anterior lateral surface of the body of the radius. It functions as a stabilizer of the scapula, acts as a protractor when reaching forward or pushing, and aids in rotation of scapula. There's a lot to learn about the anatomy of the upper limb muscles. Read more. Hip Muscles | Anatomy, Support & Movement, Pectoralis Major Action, Function, Insertion & Origin, Erector Spinae Action, Origin & Insertion | Iliocostalis, Longissimus & Spinalis, Teres Major Muscle Action, Origin & Insertion | Teres Major Location, Multifidus Muscle | Origin, Insertion & Action, Pectoralis Minor | Origin, Action & Insertion, Establishing Boundaries in Massage Therapy, Deltoid Muscle Action, Origin & Insertion | Deltoid Muscle Function. All content published on Kenhub is reviewed by medical and anatomy experts. Semispinalis capitis: Origin: transverse processes of C7-T12. The masseter muscle is the prime movermuscle for chewing because it elevates the mandible (lower jaw) to close the mouth, and it is assisted by the temporalis muscle, which retracts the mandible. The insertion is usually distal, or further away, while the origin is proximal, or closer to the body, relative to the insertion. It commonly occurs following a fall onto an outstretched hand (FOSH). 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It inserts onto the crest of greater tubercle of the humerus. We will study these muscles in depth. A. Muscles of the Head and Neck. laterally rotates the femur with hip extension, flexes humerus, antagonist of supraspinatus Flashcard Maker: sean bennet. It acts as an abductor of the shoulder, and inserts onto the superior facet of the greater tubercle of the humerus. Muscle contraction results in different types of movement. Teres Major. Short head originates from Coracoid process. The insertions of these muscles have fibers intertwined with connective tissue and the dermis of the skin. Phew. It arises from the occipital bones, occipital protuberance and nuchal lines, as well as the spinous processes of C7 through T12. Registered Nurse, Free Care Plans, Free NCLEX Review, Nurse Salary, and much more. Resulting in the inability to straighten the digit. This muscle song will help you learn the major muscles of the human body . It is innervated by the posterior scapular nerve. It has both sternocostal and clavicular heads. Similar to the erector spinae muscles, the semispinalis muscles in this group are named for the areas of the body with which they are associated. It is innervated by the thoracodorsal nerve, a branch of the posterior cord of the brachial plexus. Avascular necrosis of the proximal segment is a common complication. This muscle is considered an accessory muscle of respiration. It also spreads the digits aparts during extension of the MP joints. Its supinating effect are maximal when the elbow is flexed. insertion: top of scapula The back muscles stabilize and move the vertebral column, and are grouped according to the lengths and direction of the fascicles. inserion: medial border of scapula The two bellies are connected by a broad tendon called the epicranial aponeurosis, or galea aponeurosis (galea = apple). Due to these attachments, contraction and muscle shortening of the biceps flexes the forearm. Deltoid muscle:This muscle is named due to its Greek delta letter shape (triangular) appearance. The origin is typically the tissues' proximal attachment, the one closest to the torso. It is the prime mover in forward reaching and pushing down. The muscles in the face create facial expression by inserting into the skin rather than onto bone. The Lymphatic and Immune System, Chapter 26. Enrolling in a course lets you earn progress by passing quizzes and exams. Tongue muscles are both extrinsic and intrinsic. Plus, get practice tests, quizzes, and personalized coaching to help you 52 Learners. From the sides and the back of the neck, the splenius capitis inserts onto the head region, and the splenius cervicis extends onto the cervical region. Due to this abducting movement, the supraspinatus is commonly referred to as the suitcase muscle; i.e. An error occurred trying to load this video. The splenius group includes the splenius capitis and the splenius cervicis. The longus is innervated by the radial nerve and the brevis by the posterior interosseous branch. Flexor carpi muscles: In the superficial layer of the forearm is where we find flexor carpi radialis, and flexor carpi ulnaris. The thyrohyoid muscle also elevates the larynxs thyroid cartilage, whereas the sternothyroid depresses it. Muscle Name or Group Origin Insertion Action. It is innervated by the musculocutaneous nerve. In our cheat sheets, youll find the origin(s) and insertion(s) of every muscle. Do Humans Have an Open or Closed Circulatory System? The medial head arises from the posterior surface of the humerus below the radial groove. The humeral head arises from the medial supracondylar ridge of the humerus and the coronoid process of the ulna. All other trademarks and copyrights are the property of their respective owners. The tendon is kept close to the bones by a series of flexor tendon sheaths, which lubricate the tendon and prevent bowstringing (excessive loss of proximal pulley). The muscle also forms the medial border of the cubital fossa. See at a glance which muscle is innervated by which nerve. The sternocleidomastoid divides the neck into anterior and posterior triangles. It inserts onto the spine of the scapula, acromion, and lateral third of the clavicle. Origin: Ischial tuberosity The suprahyoid muscles raise the hyoid bone, the floor of the mouth, and the larynx during deglutition. Levator scapulae muscle:This is a deep small muscle that inserts onto the superior angle and superior medial scapular border. Our opposable thumb is essential to our advancement as a species. Flexor pollicis longus muscle:This muscle is found superficially within the deep layer. Generally the muscles in the same compartment insert into the same bone. It acts to pronate the forearm and weakly flex the elbow. This mnemonic recalls the four intrinsic muscles of the hand innervated by the median nerve, whereas all the other intrinsic muscles are ulnar nerve: F: flexor pollicis brevis. However, the scapula is integral to the movement of the shoulder via the rotator cuffand additional muscles. Last Played February 22, 2022 - 12:00 am There is a printable worksheet available for download here so you can take the quiz with pen and paper. It is also capable of weakly supinating and pronating the forearm. The lower subscapular nerve innervates the muscle and it is a branch of the posterior cord of the brachial plexus. The clavicular head enables the muscle to act as a flexor (decrease angle between joints) of arm at the shoulder and the sternocostal head enables the muscle to act as an extensor (increase angle between joints). For . Grounded on academic literature and research, validated by experts, and trusted by more than 2 million users. Origin: Flexor digitorum profundus (FDP) Insertion: Extensor hood on radial side (lateral bands) Function: Flex MCP joint and extend PIP joint Innervation. They also contribute to deep inhalation. Shahab Shahid MBBS The longissimus group includes the longissimus capitis, the longissimus cervicis, and the longissimus thoracis. I would honestly say that Kenhub cut my study time in half. For origins and insertions, I learned the exceptions in each compartment/the ones that stick out. Thenar eminence:It consists of three muscle: flexor pollicis brevis, abductor pollicis brevis, and the opponens pollicis. The biceps brachii originates on the front of the scapula of the shoulder and inserts on the front of the radius in the forearm. [3] Origin and Insertion The posterior muscles of the neck are primarily concerned with head movements, like extension. Finally, the scalenes include the anterior scalene, middle scalene, and posterior scalene. The common flexor origin is the medial epicondyle. 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Muscle Origin, Insertion, and Action - 1 by AshPopRox 4,509 plays 11 questions ~30 sec English 11p More 6 too few (you: not rated) Tries Unlimited [?] The middle fibers retract (adduct). Sample Decks: Muscles Actions, Origins, and Insertions of the Pelvic Complex and Hip (week 5), The Structure of The Knee Joint (week 6), The Foot and Ankle (week 6) Show Class. The iliocostalis group includes the iliocostalis cervicis, the iliocostalis thoracis, and the iliocostalis lumborum. origin: cervical vertebrae Due to these attachments, the triceps is stretched during forearm flexing. Pronator teres muscle is the larger of the pronator muscles and has two heads. The Cardiovascular System: Blood, Chapter 19. Commonly referred to as impingement syndrome. Insertion inferior border of 12th rib and iliolumbar ligament and ((transverse process of L1-L4)) There are several small facial muscles, one of which is the corrugator supercilii, which is the prime mover of the eyebrows. The genioglossus depresses the tongue and moves it anteriorly; the styloglossus lifts the tongue and retracts it; the palatoglossus elevates the back of the tongue; and the hyoglossus depresses and flattens it. Don't forget to quiz yourself on the forearm flexors and extensors to consolidate your knowledge! Both these muscles are known as the punching muscles as they contribute to radial deviation of the wrist, which is essential for boxers. Flexor digitorum superficialis muscle:This muscle is located in the intermediate layer and has two heads. Finally, synergist muscles enhance the action of the agonist. It acts to support the extensor digitorum muscle in extending the index finger and wrist. Opponens pollicis acts to oppose the thumb with the other digits (rotation of the thumb to pulp of the other fingers and not just flex across the palm). Mnemonics to remember bones Pectoralis minor inserts onto the coracoid process of the scapula. Do you want an efficient way to remember the arm muscles? 1 / 24. Hamstring Anatomy Mnemonics - Origin, Insertion, Innervation & Action No views Aug 11, 2022 0 Dislike Share Save Memorize Medical 125 subscribers Easy ways to learn and remember the. The hand (manual region) is the terminal end and focus of the upper limb. Get instant access to this gallery, plus: Introduction to the musculoskeletal system, Nerves, vessels and lymphatics of the abdomen, Nerves, vessels and lymphatics of the pelvis, Infratemporal region and pterygopalatine fossa, Meninges, ventricular system and subarachnoid space, Extensor carpi radialis longus and brevis, Pectoralis major, Pectoralis minor, Deltoid, Latissimus dorsi, Supinator, Extensor digitorum, Extensor carpi ulnaris, Extensor carpi radialis longus and brevis, Extensor indicis proprius, Extensor digiti minimi, Brachioradialis, Thenar eminence, Hypothenar eminence, Interossei, Lumbricals, Inferior angle and lower part of the lateral border of the scapula, Intertubercular sulcus (medial lip) of the humerus, Adduction and medial rotation of the humerus (arm), Lateral border of the scapula (middle part), Greater tubercle of the humerus (inferior facet), Lateral rotation of the arm, stabilization of the humerus as part of the rotator cuff muscles, Greater tubercle of the humerus (middle facet), Greater tubercle of the humerus (superior facet), Assistance in arm abduction,stabilization of the humerus as part of the rotator cuff muscles, Medial rotation of the arm,stabilization of the humerus as part of the rotator cuff muscles, Transverse process of the atlas and axis, posterior tubercles C3 and C4, Posterior surface of the medial scapular border (from the superior angle to the root of the spine of the scapula), Anterior rami of the nerves C3 and C4, dorsal scapular nerve (branch of the C5), Superior nuchal line, external occipital protruberance, nuchal ligament, spinous processes of C7 to T12 vertebrae, Lateral third of the clavicle, acromion and spine of the scapula, Spinal accessory nerve; C3 and C4 spinal nerves, Elevation, depression, and retraction of the scapula, Medial half of the clavicle (clavicular head); anterior surface of the sternum, 1st to 6th costal cartilages, aponeurosis of, Adduction and medial rotation of the humerus, Anterior surface of the 3rd, 4th, and 5th ribs and the fascia overlying the intercostal spaces, Medial border and superior surface of the coracoid process of the scapula, Protraction of the scapula, pulls the coracoid process anteriorly and inferiorly, accessory muscle in respiratory, Lateral third of the clavicle, acromion, and spine of scapula, Abduction and stabilization of the shoulder joint, Spinous processes of T7-L5 and sacrum, iliac crest, X-XII ribs, Distal half of the anterior side of the humerus and intermuscular septa, Flexion of the forearm at the elbow joint, Flexion of the forearm at the elbow joint, supinator of the forearm, accessory flexor of the arm at the glenohumeral joint, Anterior surface of the ulna (distal quarter), Anterior surface of the radius (distal quarter), Forearm pronationand binding of the radius and ulna, Anterior surface of the radius and interosseous membrane, Proximal parts of the anterior and lateral surfaces of the ulna and interosseous membrane, Bases of the phalanges of the 4th and 5th digits (medial part), bases of the phalanges of the 2nd and 3rd digits (lateral part), Ulnar nerve (medial part), anterior interosseous nerve (lateral part), Flexion of the distal phalanges at the interphalangeal joints of the 4th and 5th digits (medial part) and of the 2nd and 3rd digits (lateral part), Medial epicondyle of the humerus and coronoid process of the ulna (humero-ulnar head) and superior half of anterior border (ulnar head), Shafts of middle phalanges of medial four digits, Flexion of middle phalanges at proximal interphalangeal joints and flexion of the proximal phalanges at the metacarpophalangeal joints of the middle four digits, Medial epicondyle of the humerus (common flexor tendon), Flexor retinaculum and palmar aponeurosis, Medial epicondyle of the humerus (humeral head), coronoid process of the ulna (ulnar head), Lateral epicondyle of the humerus, crest of the ulna, supinator fossa, radial collateral and anular ligaments, Surface of the proximal third of the radial shaft, Posterior surfaces of the middle and distal phalanges (2nd-5th), Posterior interosseus nerve (branch of the radial nerve), Extension of the index, middle, ring and little fingers, Lateral epicondyle of the humerus, posterior border of the ulna, Medial side of the base of the metacarpal V, Posterior side of the distal third of the ulnar shaft; interosseous membrane, Proximal two-thirds of the supra-epicondylar ridge of the humerus, Lateral surface of the distal end of the radius, Forearm flexion, especially during mid-pronation, Flexor retinaculum and tubercle of trapezium and scaphoid bones, Thumb flexion, abduction, and medial rotation resulting in a combined movement called opposition, Abduction of the 5th digit and flexion assistance of the proximal phalanx, Base of the proximal phalanx of the 5th digit, Flexion of the proximal phalanx of the 5th digit, Sides of two adjacent metacarpals (dorsal interossei) and palmar surfaces of the 2nd, 4th, 5th metacarpals (palmar interossei), Bases of the proximal phalanges via the extensor expansions of the 2nd to 4th digits (dorsal interossei) and 2nd, 4th, and 5th digits (palmar interossei), Abduction of the 2nd to 4th digits (dorsal interossei), adduction of the 2nd, 4th, and 5th digits (palmar interossei), assisting the lumbricals in extension, Tendons of the flexor digitorum profundus, Lateral expansions of the 2nd to 5th digits, Flexion of the metacarpophalangeal joints and extension of the interphalangeal joints of the 2nd to 4th digits.