muscle mnemonics origin, insertion action muscle mnemonics origin, insertion action

The acronym for the rotator cuff is S.I.T.S. TABLE: Origin, Insertion, and Action for Lecture Checklist: Selected Human Muscles. It arises from the spinous processes of the T7-L5 (L = Lumbar) vertebrae, costals 8-12, inferior angle of the scapula, and iliac crest. Phew. The neurovascular bundle (intercostal nerve, artery and vein) will separate these two muscles. Why are the muscles of the face different from typical skeletal muscle? | 15 For example, one could say the wrist is distal to the elbow. Some People Bang Like Monkeys. Rhomboid minor muscle:This is a smaller muscle with the same shape as the rhomboid major and lies above it. 'Rule of 3s' and 'Busy BeesCollaBorate well'. It is innervated by the posterior scapular nerve. The muscles of the head and neck are all axial. Here's a mnemonic that summarizes the brachioradialis and helps you to remember it. Curated learning paths created by our anatomy experts, 1000s of high quality anatomy illustrations and articles. Kenhub. The muscle acts to supinate the forearm and forms the lateral border of the cubital fossa. The posterior muscles of the neck are primarily concerned with head movements, like extension. It acts to extend the pinky as well as the wrist. The Cardiovascular System: Blood, Chapter 19. This results in a restricted range of motion. It passes anteriorly and around the thoracic cage as if wrapping. It is the prime mover in forward reaching and pushing down. Insertion: Medial proximal condyle of tibia Action: Extends thigh, flexes leg, Origin: Lateral condyle and proximal tibia Insertion: First metatarsal and first cuneiform Action: Dorsiflexes and inverts foot, Origin: Condyles of femur Insertion: Calcaneus by calcaneal tendon Action: Flexes leg, plantar flexes foot, Origin:Posterior, proximal tibia and fibula Insertion: Calcaneus by calcaneal tendon Action: Plantar flexes foot, Origin: Head and shaft of fibula, lateral condyle of tibia Insertion: First metatarsal, first cuneiform Action: Plantar flexes and everts foot, Origin: Lateral COndyle of tibia, shaft of fibula Insertion: Middle of distal phalanges of second through fifth digits Action: Extends toes, dorsiflexes foot, Origin: Inferior border of a rib Insertion: Superior border of rib below Action: Elevates ribs (increases volume in thorax), Origin: Inferior border of a rib Insertion: Superior border of rib below Action: Depresses ribs (decreases volume in thorax), Origin: Posterior occipital bone, ligamentum nuchae, C7-T12 Insertion: Clavicle, Acromion process, and spine of scapula Action: Extends and abducts head, rotates and adducts scapula, fixes scapula, Origin: Spines of T2-5 Insertion: Lower one-third of vertebral border of scapula Action: retraction of scapula, Origin: Ligamentum nuchae, Spines C7-T1 Insertion: Vertebral border of scapula at scapular spine Action: retraction of scapula, Origin: Galea aponeurotica Insertion: Skin superior to orbit Action: Raises eyebrows, draws scalp anteriorly, Origin: Fascia of facial muscles near mouth Insertion: Skin of lips Action: Closes lips, Origin: Frontal and maxilla on medial margin of orbit Insertion: Skin of eyelid Action: Closes eyelid, Origin: Zygomatic arch Insertion: Angle and ramus of mandible Action: Closes mandible, Origin: Temporal fossa Insertion: coronoid process and ramus of mandible Action: Closes mandible, Origin: Sternum, clavicle Insertion: Mastoid process of temporal Action: Abducts, rotates, and flexes head, Origin: Ribs 1-8 Insertion: Vertebral border and inferior angle of scapula Action: Abducts scapula (moves scapula away from spinal column), Origin: Bottom of rib cage, Crest of pubis, symphysis pubis Insertion: xiphoid process, Origin: Ribs 5-12 Insertion: Linea alba, iliac crest, pubis Action: Compresses abdominal wall, laterally rotates trunk, Origin: Inguinal ligament, iliac crest Insertion: Linea alba, ribs 10-12 Action: Compresses abdominal wall, laterally rotates trunk, Origin: the inner surface of the 7th to 12th costal cartilages, the thoracolumbar fascia, the iliac crest horizontally, and the inguinal ligament Insertion: linea alba Action: support for the abdominal wall, directly on top of the sciatic nerve 190 lessons 1 / 24. The thyrohyoid muscle also elevates the larynxs thyroid cartilage, whereas the sternothyroid depresses it. 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. 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 [?] Plus, get practice tests, quizzes, and personalized coaching to help you It inserts into the medial aspect of the 5th metacarpal. Explain the difference between axial and appendicular muscles. Here's a mnemonic to help you remember the innervation of the lumbricals more easily! Author: The action makes sense when you consider the muscle's points of attachment. The triceps is the antagonist, and its action opposes that of the agonist. Finally, synergist muscles enhance the action of the agonist. This also helps you understand its action (s) as well as what injuries may be present if there is pain in relevant areas. Resulting in the inability to straighten the digit. The origin is typically the tissues' proximal attachment, the one closest to the torso. The common flexor origin is the medial epicondyle. Both of these muscles are innervated by the anterior interosseous branch. These are innervated by the ulnar nerve. Due to these attachments, the triceps is stretched during forearm flexing. It is important to note that the scapula does articulate with the acromial end of the clavicle forming the acromioclavicular joint (AC joint), as well as the humeral head with the scapular glenoid cavity (fossa) which forms the glenohumeral joint. The geniohyoid depresses the mandible in addition to raising and pulling the hyoid bone anteriorly. The Nervous System and Nervous Tissue, Chapter 13. It is innervated by the thoracodorsal nerve, a branch of the posterior cord of the brachial plexus. Intrinsic muscles of the hand (mnemonic) - Radiopaedia 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. Muscles always pull. It functions as a stabilizer of the scapula, acts as a protractor when reaching forward or pushing, and aids in rotation of scapula. Those in the same compartment will have the same action. Hypothenar eminence:It consists of the flexor digiti minimi brevis, the abductor digiti minimi brevis, and the opponens digiti minimi. It's important to note that the antagonist contraction is minor in comparison to the agonist contraction, and therefore it doesn't prevent the action of the agonist. Extensor carpi radialis longus and brevis muscles:The longus muscle arises from the lateral epicondylar ridge and inserts onto the dorsal surface of the 2nd metacarpal. Some of the axial muscles may seem to blur the boundaries because they cross over to the appendicular skeleton. The muscles are named after their functions, with the flexor muscle medial most, the abductor lateral most, and the opponens muscle lying deep. Kinesiological Analysis: Description & Major Components, Massage Therapy Scope of Practice | Overview, Purpose & Manipulation. action: elevates scapula, The posterior hamstring muscle group - The common extensor origin is the lateral epicondyle. The transversospinales include the semispinalis capitis, semispinalis cervicis, semispinalis thoracis, multifidus, and rotatores. Curated learning paths created by our anatomy experts, 1000s of high quality anatomy illustrations and articles. It also spreads the digits aparts during extension of the MP joints. Axial muscles originate on the axial skeleton (the bones in the head, neck, and core of the body), whereas appendicular muscles originate on the bones that make up the bodys limbs. A synergist is a muscle that enhances the action of the agonist. It has an essential role in initiating the first 15 degrees of abduction (move away from the body). In that manner of speaking, this article will explain all the anatomical aspects of the muscles of the scapula, arm, forearm and hand. Don't forget to quiz yourself on the forearm flexors and extensors to consolidate your knowledge! It is caused by proximal interphalangeal joint flexion, and distal interphalangeal joint extension. The patient will present with tenderness within the anatomical snuffbox. The clavicular head arises from the medial two thirds of the inferior surface of the clavicle. Serratus anterior muscle:This muscle is so named due to its anterior digitations that have a serrated or finger-like appearance. The upper limb(upper extremity) is truly a complex part of human anatomy. It arises from the flexor retinaculum, scaphoid tubercle, and trapezium. Antagonist contractions are opposite that of the agonist and serve to control the action. It is the primary lateral rotator of the shoulder, it also modulates deltoid movement. Serratus anterior muscle: Origin, insertion and action | Kenhub It is innervated by the axillary nerve. During that particular movement, individual muscles will play different roles depending on their origin and insertion. Bony Landmarks Types & Identification | What are Femur Landmarks? Muscle origins and insertions Many muscles are attached to bones at either end via tendons. Teres major:This muscle arises from the posterior surface of the inferior scapular angle and inserts onto the medial lip of the intertubercular sulcus of the humerus. Muscles of the Upper Limb Pectoralis minor ORIGIN: anterior surface of ribs 3 - 5 ACTION INSERTION: coracoid process (scapula) Muscles Stabilizing Pectoral Girdle INNERVATION: pectoral nerves: protracts / depresses scapula (Anterior view) Serratus anterior ORIGIN: ribs 1 - 8 INSERTION: ACTION medial border of scapula stabilizes / depresses This muscle also prevents the humeral head from moving too far upwards while the deltoidis in action, as do all the rotator cuff muscles. It acts to flex the elbow. Get unlimited access to over 88,000 lessons. The third group, the spinalis group, comprises the spinalis capitis (head region), the spinalis cervicis (cervical region), and the spinalis thoracis (thoracic region). The muscles acts to flex the proximal IP joints as it primary function. It acts as an abductor of the shoulder, and inserts onto the superior facet of the greater tubercle of the humerus. Because of its mobility, the tongue facilitates complex speech patterns and sounds. Do you want an efficient way to remember the arm muscles? It inserts onto the radial aspect of the 1st metacarpal. There are numerous muscles in this compartment. All rights reserved. Get your muscle charts below. Inferior dislocations are the least common and make the upper limb appears as if you are holding your upper limb upwards. Reading time: about 1 hour. A skeletal muscle attaches to bone (or sometimes other muscles or tissues) at two or more places. Conversely, you can say the elbow is proximal to the wrist. The muscle arises from costals (ribs) 1 - 8, sometimes terminating origins at costal 9. Pronator quadratus muscle:In the deepest layer of the forearm is the pronator quadratus, which is found connecting the radius (insertion) and ulna (origin) at their distal points like a strap. Register now Muscle origins and insertions dictate the type of movement that occurs when a muscle contracts. Human muscles - TABLE: Origin, Insertion, and Action for - Studocu and grab your free ultimate anatomy study guide! Muscle anatomy reference charts: Free PDF download | Kenhub A: abductor pollicis brevis. Subjects: action comments insertion muscles nerve origin skeletal . Supraspinatus tears result in inability to initiate shoulder abduction. Leif Saul, University of Colorado In anatomical terminology, chewing is called mastication. Most skeletal muscles create movement by actions on the skeleton. It controls extension, lateral flexion, and rotation of the vertebral column, and maintains the lumbar curve. It has three heads: long, lateral, and medial. Many muscles are attached to bones at either end via tendons. Origin: Inferior angle of scapula. A FOSH may fracture the bone. It inserts onto the crest of greater tubercle of the humerus. 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. flashcard sets. Last reviewed: November 03, 2021 The muscle causes flexion of the wrist and ulnar deviation when its acts with extensor carpi ulnaris. Have you triedour upper limb muscle anatomy revision chartyet? Action: Extends thigh, flexes leg, Narrower than semimembranosus As the muscles contract, they exert force on the bones, which help to support and move our body along with its appendages. Most skeletal muscle is attached to bone on its ends by way of what we call tendons. In this anatomy muscle song, you can learn rhymes and mnemonics to help you remember the muscle name, location, and one of its functions/actions. The good news? The omohyoid muscle, which has superior and inferior bellies, depresses the hyoid bone in conjunction with the sternohyoid and thyrohyoid muscles. This muscle is considered an accessory muscle of respiration. There are two main ones, so lets break em in half. The longissimus group includes the longissimus capitis, the longissimus cervicis, and the longissimus thoracis. Easy way to learn muscles? (Origin and insertion) The nerve supply comes from the upper and lower subscapular. succeed. As the muscles pass anteriorly to the MP joints and insert they cause flexion of the MP joint and extension of the IP joints. It acts to draw the scapula lateral, forward, downward, and stabilizes the scapula. The styloglossus originates on the styloid process of the temporal bone, and allows upward and backward motion. Its supinating effect are maximal when the elbow is flexed. It arises from the nuchal ligament and spinous processes of C7 to T1. S: supraspinatus I: infraspinatus T: teres minor S: subscapularis With 'SITS', recalling this order also helps remember the insertions of these muscles, with the order being superior, middle, and inferior facets of the greater tubercle of the humerus for supraspinatus, infraspinatus and teres minor respectively and . For example, that same muscle, the biceps brachii, performs flexion at the elbow, in which the elbow is the joint. See our full, Click to share on Facebook (Opens in new window), Click to share on Twitter (Opens in new window), Click to share on Pinterest (Opens in new window), Click to share on Reddit (Opens in new window), Click to share on LinkedIn (Opens in new window), Click to share on WhatsApp (Opens in new window), Click to share on Pocket (Opens in new window), Click to share on Telegram (Opens in new window), Click to share on Skype (Opens in new window), IV Drug Use Complications & Dangers: (Endocarditis, Infection, Infectious Diseases). Pectoral Muscles Anatomy - Mnemonic for upper chest muscles | 3d The muscle inserts onto the anterior lateral surface of the body of the radius. You will feel the movement originate there. posterior muscles - gluteus maximus muscle (the largest muscle in the body) and the hamstrings group, which consists of the biceps femoris, semimembranosus, and semitendinosus muscles. Muscular contraction produces an action, or a movement of the appendage. It is innervated by the posterior interosseous branch. It pronates the radius and is innervated by the anterior interosseous branch of the median nerve. The information we provide is grounded on academic literature and peer-reviewed research. This complete MBLEx prep course covers all sections of the FSMTB Massage & Bodywork Licensing Exam, and includes full MBLEx practice tests and quizzes. This muscle allows you to whistle, blow, and suck; and it contributes to the action of chewing. The Lymphatic and Immune System, Chapter 26. Grounded on academic literature and research, validated by experts, and trusted by more than 2 million users. The major muscle that laterally flexes and rotates the head is the sternocleidomastoid. I feel like its a lifeline. Muscles of the Pectoral Girdle and Upper Limbs Raise your eyebrows as if you were surprised and lower your eyebrows as if you were frowning. Enter your email address below and hit "Submit" to receive free email updates and nursing tips. I highly recommend you use this site! The hand is truly the epitome of anatomical complexity. The shoulder is most unstable in extension and external rotation. The brevis muscle arises from the lateral epicondyle and inserts onto the dorsal base of the 3rd metacarpal. It acts to pronate the forearm and weakly flex the elbow. Enrolling in a course lets you earn progress by passing quizzes and exams. This muscle song will help you learn the major muscles of the human body . Rotator cuff (mnemonic) | Radiology Reference Article - Radiopaedia It acts to extend the wrist and also contributes to radial deviation of the wrist. I would honestly say that Kenhub cut my study time in half. The closer we move to the hand the more muscles we begin to have, as our movements require finer and finer gradations. The muscle can be divided into three sets of fibers: upper, middle, and lower. The opponens digiti minimi arises from the hook of hamate and flexor retinaculum. 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). It is also innervated by the median nerve. Thenar eminence:It consists of three muscle: flexor pollicis brevis, abductor pollicis brevis, and the opponens pollicis. Shoulder Muscles Anatomy - Simplified | Epomedicine There's a lot to learn about the anatomy of the upper limb muscles. Muscle memory is a form of procedural memory that involves consolidating a specific motor task into memory through repetition, which has been used synonymously with motor learning. 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). The two bellies are connected by a broad tendon called the epicranial aponeurosis, or galea aponeurosis (galea = apple). 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. Therefore, when they contract, the origin pulls the insertion and connected bone closer . This is a bony deformity of the finger or toes associated with rheumatoid arthritis and trauma to the end of the extended finger. Diaphragm *Note the distinction between internal and innermost intercostal. The muscles discussed below are essential to everyday life and advanced movements such as writing. 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, Anterior, medical and posterior thigh muscles, Anterior, lateral and posterior leg muscles, Thenar, hypothenar and metacarpal muscles of the hand, Muscles of facial expression and mastication. The layman will refer to the entire upper limb as the arm. The medial head is supplied by the ulnar nerve, and the lateral head by the anterior interosseous branch. Kenhub. Origin: Clavicle, acromion process, spine of scapula Insertion: Deltoid tuberosity of the humerus Action: Abducts arm; flexes, extends, medially, and laterally rotates arm. Insertion inferior border of 12th rib and iliolumbar ligament and ((transverse process of L1-L4)) Definition. Lumbricals:These are worm like muscles that originate from the tendons of the flexor digitorum profundus. It has a long head and a short head. Due to this abducting movement, the supraspinatus is commonly referred to as the suitcase muscle; i.e. It may seem strange that it is included in the anatomy of the upper limb. Muscles of the Posterior Neck and the Back. The nerve supply to this muscle arises from the axillary nerve, a branch of the posterior cord of the brachial plexus. Iliacus muscle. The middle fibers retract (adduct). Read more. The iliocostalis group includes the iliocostalis cervicis, the iliocostalis thoracis, and the iliocostalis lumborum. The brachialis originates on the humerus, and it inserts on the front of the ulna. 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. Each of these muscles has a name; for example, again, the biceps brachii and now the triceps brachii, responsible for both forearm flexion and forearm extension, respectively. Skeletal Muscles (Comments, Origin, Insertion, Action, Nerve) by melissa1780d, Mar. The damaged nerve causes a weakened serratus anterior, leading to the scapula not being pulled down and in during circumduction. 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. These insert into the 2nd - 5th proximal phalanges. 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.