Structures of the Hand PPT
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The document provides an overview of the human hand's anatomy, covering its bones, ligaments, muscles, and innervation, along with common hand conditions such as arthritis, Dupuytren's contracture, carpal tunnel syndrome, and trigger finger. Key anatomical features include the hand's 27 bones, its arches, and the role of various muscles in hand movements. It emphasizes the complexity and functional significance of the hand in prehensile activities and tactile feedback.
Structures of the Hand PPT
- 1. The Structures of the Hand i.e. Anatomy of the Hand Stacey Louisa Bock Occupational Therapist, Namakwa District Only certain structures will be discussed! There’s TOOOO much!
- 3. TODAY 21/10/2013 • The anatomy of the hand • Bones • Areas • Zones • Arches • Ligaments • Muscles • Innervation • Test on the anatomy of the hand • Brief overview of the infamous hand conditions • Article: Hand Anatomy, Medscape
- 4. A hand (manus, pl. manūs) ⥤...is a prehensile, multi-fingered extremity located at the end of an arm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs. ⥤...& are the richest source of tactile feedback, and have the greatest positioning capability of the body; thus the sense of touch is intimately associated with hands. ⥤...each hand is dominantly controlled by the opposing brain hemisphere, so that handedness, or the preferred hand choice for single-handed activities such as writing with a pencil, reflects individual brain functioning.
- 5. BONES The human hand has 27 bones, not including the sesamoid bones which number varies between people. 14 of which are the phalanges (proximal, intermediate and distal) of the fingers. The metacarpals are the bones that connects the fingers and the wrist. Each human hand has 5 metacarpals and 8 carpal bones.
- 6. Hamate … Pisiform… Triquetrum… … Trapezoid …Trapezium … Capitate Lunate… …Scaphoid
- 7. AREAS Areas of the human hand include: The palm (Volar), which is the central region of the anterior part of the hand, located superficially to the metacarpus. The opisthenar area (dorsal) is the corresponding area on the posterior part of the hand. The heel of the hand is the area anteriorly to the bases of the metacarpal bones, located in the proximal part of the palm. It is the area that sustains most pressure when using the palm of the hand for support, such as in a handstand. PALMAR DORSAL
- 8. ZONES Extensor Zones of Hand
- 9. ARCHES ARCHES OF THE HAND Red: one of the oblique arches Brown: one of the longitudinal arches of the digits Dark green: transverse carpal arch Light green: transverse metacarpal arch
- 10. LIGAMENTS The flexor retinaculum (transverse carpal ligament, or anterior annular ligament) is a strong, fibrous band that arches over the carpus, converting the deep groove on the front of the carpal bones into a tunnel, the carpal tunnel, through which the Flexor tendons of the digits and the median nerve pass.
- 11. The extensor retinaculum (dorsal carpal ligament, or posterior annular ligament) is an anatomical term for the thickened part of the antebrachial fascia that holds the tendons of the extensor muscles in place. It is located on the back of the forearm, just proximal to the hand. It is continuous with the palmar carpal ligament, which is located on the anterior side of the forearm.
- 12. The palmar aponeurosis (palmar fascia) invests the muscles of the palm, and consists of central, lateral, and medial portions. CENTRAL PORTION The central portion occupies the middle of the palm, is triangular in shape, and of great strength and thickness.
- 13. MUSCLES The muscles acting on the hand can be subdivided into two groups: extrinsic intrinsic The extrinsic muscle groups are the long flexors and extensors. They are called extrinsic because the muscle belly is located on the forearm. The intrinsic muscle groups are the thenar (thumb) and hypothenar (little finger) muscles; the interossei muscles (four dorsally and three volarly) originating between the metacarpal bones; and the lumbrical muscles arising from the deep flexor (and are special because they have no bony origin) to insert on the dorsal extensor hood mechanism.
- 14. FLEXORS Flexor Digitorum Profundus Origin Anterior ulna and interosseous membrane Insertion By 4 tendons, each to the base of the distal phalanx of digits 2-5 Innervation Medial half: Ulnar n. Lateral half: Median n. Action MCP, PIP and DIP flexion, wrist flexion
- 15. Flexor Digitorum Superficialis Origin Common flexor tendon on the medial epicondyle of the humerus, coronoid process of the ulna and radius lateral to the bicipital tuberosity Insertion By 4 tendons, each to the sides of the middle phalanges of the fingers Innervation Median n. Action MCP and PIP flexion
- 16. Flexor Pollicis Longus Origin Middle anterior portion of the radius and interosseous membrane Insertion Base of the distal phalanx of the thumb Innervation Median n. Action CMC, MCP and IP flexion of the thumb
- 17. STRETCH BREAK! 3 MINUTES!
- 18. EXTENSORS Extensor Digitorum Origin Lateral epicondyle of the humerus-common extensor tendon Insertion By 4 tendons, each to the base of the extensor mechanism and base of the proximal phalanx of all 4 fingers Innervation Radial n. Action Extensionof the fingers
- 19. Extensor Indicis Origin Posterior surface of distal ulna and interosseous membrane Insertion Blends with the index tendon of the extensor digitorum Innervation Radial n. Action Extension of the index finger
- 20. Extensor Digiti Minimi Origin Ulnar side of the belly of the extensor digitorum Insertion Joins the tendon of the extensor digitorumto the little finger Innervation Radial n. Action Extension of the 5th finger
- 21. Extensor Pollicus Longus Origin Posterior surface of the ulna and interosseous membrane Insertion Dorsal base of the distal phalanx of the thumb Innervation Radial n. Action Extension of the IP, MCP and CMC of the thumb
- 22. Extensor Pollicus Brevis Origin Posterior aspect of the radius and interosseous membrane Insertion Dorsal base of the proximal phalanx of the thumb Innervation Radial n. Action Extension of the MCP & CMC joints of the thumb
- 23. ABDuctor Pollicis Longus Origin Posterior surface of the radius, ulna and interosseous membrane Insertion Base of the 1stmetacarpal Innervation Radial n. Action ABD and extension of the CMC of the thumb
- 24. “ANATOMIC SNUFF BOX” Extensor Pollicis Longus Extensor Pollicis Brevis ABDuctor Pollicis Longus
- 25. INNERVATION CUTANEOUS INNERVATION OF THE UPPER LIMB The hand is innervated by the radial, median, and ulnar nerves. All muscles of the hand are innervated by the brachial plexus (C5–T1) and can be classified by innervation: Radial Median Ulnar Extensors: carpi radialis longus and brevis, digitorum, digiti minimi, carpi ulnaris, pollicis longus and brevis, and indicis. Other: abductor pollicis longus. . Flexors: carpi radialis, pollicis longus, digitorum profundus (half), superficialis, and pollicis brevis (superficial head). Other: palmaris longus. abductor pollicis brevis, opponens pollicis, and first and second lumbricals. Flexor carpi ulnaris, flexor digitorum profundus (half), palmaris brevis, flexor digiti minimi, abductor digiti minimi, opponens digiti minimi, adductor pollicis, flexor pollicis brevis (deep head), palmar and dorsal interossei, and third and fourth lumbricals.
- 26. MY ARCHES NAME OF THE HAND Red: one of the oblique arches IS WHAAAAT??!! Brown: one of the longitudinal arches of the digits Dark green: transverse carpal arch Light green: transverse metacarpal arch
- 27. THE INFAMOUS HAND CONDITIONS Arthritis General clinical picture: The typical picture of an RA hand is as follows: Synovitis on the dorsum of the wrist. The wrist may be in radial deviation. In some cases volar subluxation may also be present. In RA seen in black South Africans, wrist involvement may be the only manifestation. The MP joints are in ulnar deviation and flexion. This may be combined with volar subluxation. At the PIP joint level, boutonnière and swanneck deformities may be present in the same hand. DIP joints are seldom involved. There may be swelling and crepitations of the flexor tendons, which may cause carpal tunnel syndrome or triggering Shoulder involvement includes swelling, stiffness and pain.
- 28. Dupuytren's contracture… is another disorder of the fingers that is due to thickening of the underlying skin tissues of the palm. The disorder results in a deformed finger which appears thin and has small bumps on the surface. Dupuytren's contracture does run in families, but is also associated with diabetes, smoking, seizure recurrence and other vascular disorders.
- 29. Ganglion cysts are soft globular structures that occur on the back of the hand usually near the junction of the wrist joint. These small swellings are usually painless when small but can affect hand motion when they become large. The cysts contain a jelly like substance and usually do disappear on their own. If the ganglion cyst is not bothersome, it should be left alone. Just removing the fluid from the cyst is not curative because fluid will come back in less than a week.
- 30. CARPAL TUNNEL SYNDROME Carpal tunnel syndrome is a common disorder of the hand. This disorder results from compression of an important nerve in the wrist. Disorders like diabetes mellitus, thyroid or rheumatoid arthritis can narrow the tunnel and cause impingement of the nerve. Carpal tunnel syndrome also occurs in people who overuse their hand or perform repetitive actions like using a computer key board, a cashiers machine or a musical instrument. When the nerve is compressed, it can result in disabling symptoms like numbness, tingling, or pain in the middle three fingers.
- 31. DE QUERVAINS’S DISEASE Clinical signs and symptoms APL and EPL are stuck in the tunnel(s) at the radial side of the distal radius This area may be very prominent, swollen and tender because of the synovitis Thumb flexion together with wrist ulnar deviation, and thumb abduction is painful Percussion over the tunnel can be excruciatingly painful Assessment Finkelstein test: Thumb flexion (gripping thumb with other fingers) together with wrist ulnar deviation. (see illustration below) -This is extremely painful and unbearable for patient –almost unable to do This condition occurs frequently in patients with osteo arthritis. It is described as stenosing tenosynovitis (inflammation) of the tendon sheaths of the Abductor pollicis longus and Extensor pollicis brevis (APL & EPB) tendons, which is often caused by excessive unusual repetitive movements of the thumb. This is also described as inflammation within the tendon sheaths causing narrowing of the lumens (The space where the tendon is gliding through)
- 32. TRIGGER FINGER Trigger finger is a common disorder which occurs when the sheath through which tendons pass, become swollen or irritated. Initially, the finger may catch during movement but symptoms like pain, swelling and a snap may occur with time. The finger often gets locked in one position and it may be difficult to straighten or bend the finger. Trigger finger has been found to be associated with diabetes, gout and rheumatoid arthritis.
- 33. NERVE PALSY
- 34. THANK YOU!!! Any questions, concerns, comments, rude remarks??
Editor's Notes
- #2: Ice breaker - Race for the truth Statements are made about the structures in the hand. All stand at the start line. If you think the statement is true, take one step forward. If you think the statement is false don’t move. But if the statement is true and you don’t move, you’re out of the game. And if the statement is false and you move, you’re out of the game. PREP THIS ALONG WITH A PRIZE There are 27 bones not including the sesamoid bones in the human hand. MOVE TRUE: small ossified nodes embedded in tendons; the exact number varies between different people. This side of your hand (show volar) is the dorsal side. STAND STILL FALSE: The hand is divided into 5 flexor zones and 8 extensor zones. MOVE The flexor reticulum is one of the ligaments found in the hand. MOVE transverse carpal ligament An example of flexion using the human hand is: a person's the hand is brought nearer to the shoulder. MOVE The human hand has 6 digits. STAND STILL The small bones in the wrist are called the carpals MOVE Carpal Tunnel Syndrome is a common hand condition. MOVE The flexor digitorum profundus is a muscle found in the forearm (volar side) and it flexes the fingers. MOVE The extensor indicis flexes the index finger STAND STILL
- #3: HAI’s?
- #4: Renowned, notorius, well-known
- #5: Prehensility means that the organ it describes has been adapted to grasp and hold. A few other vertebrates such as the koala are often described as having either "hands" or "paws" on their front limbs. Fingers are some of the densest areas of nerve endings on the body, are the richest source of tactile feedback, and have the greatest positioning capability of the body; thus the sense of touch is intimately associated with hands. Like other paired organs (eyes, feet, legs), each hand is dominantly controlled by the opposing brain hemisphere, so that handedness, or the preferred hand choice for single-handed activities such as writing with a pencil, reflects individual brain functioning.
- #6: Sesamoid bones - small ossified nodes embedded in tendons; the exact number varies between different people.
- #7: The eight short bones of the wrist or carpus organized into a proximal row (scaphoid, lunate, triquetral and pisiform), which articulates with the skeleton of the forearm, and a distal row (trapezium, trapezoid, capitate and hamate), which articulates with the bases of the metacarpal bones. Because supination and pronation (rotation about the axis of the forearm) are added to the two axes of movements of the wrist, the ulna and radius are sometimes considered part of the skeleton of the hand.
- #8: There are five digits attached to the hand. The four fingers can be folded over the palm which allows the grasping of objects. Each finger, starting with the one closest to the thumb, has a colloquial name to distinguish it from the others: index finger, pointer finger, or forefinger middle finger or long finger ring finger little finger, pinky finger, or small finger. The thumb (connected to the trapezium) is located on one of the sides, parallel to the arm. A reliable way of identifying true hands is from the presence of opposable thumbs. Opposable thumbs are identified by the ability to be brought opposite to the fingers, a muscle action known as opposition.
- #9: Flexor Zones: The hand is divided into following 5 zones, which would determine the prognosis and approach to treatment. Zone 1: Only FDP involved Loss of flx of DIP joint Instability in pinch Loss of grip strength Good prognosis Zone 2: “No man’s land” Pulleys present (prevent bow stringing) A2 and A4 Vincula in area–provide vascular supply. Injury thus causes decreased tendon vascular nutrition. Poor prognosis Zone 3: Good prognosis Good vascularity and no pulleys Zone 4: Carpal tunnel Usually more than 1 tendon involved Intendinous adhesions (close proximity of tendons) Relatively good prognosis Zone 5: Usually presents with nerve involvement (ulnar / median nerve) Tendons superficial, thus adhesions to skin probable The hand is divided into 8 zones when dealing with extensor tendon injuries.
- #10: The fixed and mobile parts of the hand adapt to various everyday tasks by forming bony arches: longitudinal arches (the rays formed by the finger bones and their associated metacarpal bones), transverse arches (formed by the carpal bones and distal ends of the metacarpal bones), and oblique arches (between the thumb and four fingers): Of the longitudinal arches or rays of the hand, that of the thumb is the most mobile (and the least longitudinal). While the ray formed by the little finger and its associated metacarpal bone still offers some mobility, the remaining rays are firmly rigid. The phalangeal joints of the index finger, however, offer some independence to its finger, due to the arrangement of its flexor and extension tendons. Together with the thumb, the four ulnar fingers form four oblique arches, of which the arch of the index finger functionally is the most important, especially for precision grip, while the arch of the little finger contribute an important locking mechanism for power grip. The thumb is undoubtedly the "master digit" of the hand, giving value to all the other fingers. Together with the index and middle finger, it forms the dynamic tridactyl configuration responsible for most grips not requiring force. The ring and little fingers are more static, a reserve ready to interact with the palm when great force is needed.
- #12: It is a strong, fibrous band, extending obliquely downward and medialward across the back of the wrist, and consisting of part of the deep fascia of the back of the forearm, strengthened by the addition of some transverse fibers.
- #13: Its apex is continuous with the lower margin of the transverse carpal ligament, and receives the expanded tendon of the palmaris longus.
- #14: In anatomy, flexion (from the Latin verb flectere, to bend)[1] is a joint movement that decreases the angle between the bones that converge at the joint. For example, a person's elbow joint is flexed when the hand is brought nearer to the shoulder. Flexion may be instigated by muscle contraction. A muscle that flexes a joint is called a flexor. In joint extension, the opposite of joint flexion, the angle of the joint increases. We will just be focusing on the extrinsic muscles as the inclusion of the intrinsic muscles would be far too much.
- #15: In human anatomy, the flexor digitorum profundus (FDP, Latin for "deep bender of the fingers") is a muscle in the forearm that flexes the fingers (also known as digits). It is considered an extrinsic hand muscle because it acts on the hand while its muscle belly is located in the forearm. Together the flexor pollicis longus, pronator quadratus, and flexor digitorum profundus form the deep layer of ventral forearm muscles.
- #16: To test flexor digitorum superficialis, one finger is flexed at the proximal interphalangeal joint against resistance, while the remaining three fingers are held fully extended (to inactivate flexor digitorum profundus). Innervation – Median nerve, and blood supply Ulnar artery
- #17: In anatomy, flexor carpi radialis is a muscle of the human forearm that acts to flex and (radial) abduct the hand.
- #18: Show the kitty clip after the break
- #19: This muscle is quite long, starting on the lateral side of the humerus, and attaching to the base of the second metacarpal bone (metacarpal of the index finger). As the name suggests, this muscle is an extensor at the wrist joint and travels along the radial side of the arm, so will also abduct (radial abduction) the hand at the wrist.[1] That is, it manipulates the wrist so as to move the hand towards the thumb (i.e., abduction—away from the mid-position of the hand) and away from the palmar side (i.e., extension—increased angle between the palm and the front of the forearm).
- #20: It is shorter and thicker than its namesake extensor carpi radialis longus which can be found above the proximal end of the extensor carpi radialis brevis.
- #21: Being an extensor muscle, extensor carpi ulnaris is on the posterior side of the forearm.
- #23: The extensor indicis extends the index finger, and by its continued action assists in extending (dorsiflexion) the wrist and the midcarpal joints. Because the index finger and little finger have separate extensors, these fingers can be moved more independently than the other fingers.
- #26: The radial nerve innervates the finger extensors and the thumb abductor, thus the muscles that extends at the wrist and metacarpophalangeal joints (knuckles); and that abducts and extends the thumb. The median nerve innervates the flexors of the wrist and digits, the abductors and opponens of the thumb, the first and second lumbrical. The ulnar nerve innervates the remaining intrinsic muscles of the hand.
- #28: Arthritis of the hand is common in females. Osteoarthritis of the hand joints is much less common then rheumatoid arthritis. As the arthritis progresses, the finger gets deformed and lose its functions. Moreover, many patients with rheumatoid arthritis have this dysfunction present in both hands and become disabled due to chronic pain. Osteoarthritis is most common at the base of thumb and is usually treated with pain pills, splinting or steroid injections.
- #29: Dupuytren's does not need any treatment as the condition can resolve on its own. However, if finger function is compromised, then surgery may be required.
- #30: Surgery is often done for large cysts but the results are poor. Recurrences are common, and there is always the possibility of nerve or joint damage.
- #31: As the condition progresses, it can lead to muscle weakness and inability to hold objects. The pain frequently occurs at night and can even radiate to the shoulder. Even though the diagnosis is straightforward, the treatment is not satisfactory.
- #32: This condition occurs frequently in patients with osteo arthritis. It is described as stenosing tenosynovitis (inflammation) of the tendon sheaths of the Abductor pollicis longus and Extensor pollicis brevis (APL & EPB) tendons, which is often caused by excessive unusual repetitive movements of the thumb. This is also described as inflammation within the tendon sheaths causing narrowing of the lumens (The space where the tendon is gliding through)