Hand and Wrist Joint

1. Hand and Wrist Joint Tana Pearson Galina Nesenchuk ViraIatchenko

2. BONES: Ulna, Radius The ulna is a long bone, prismatic in form, placed at the medial side of the forearm, parallel with the radius. • Radius

3. Bones: Ulna • Head of ulna – small, rounded surface at distal end of bone • Styloid process of ulna – small, medial projection from head region; forms medial portion of wrist joint

4. Bones: Radius • Styloid process of radius • pointed lateral projection at distal end of bone; forms lateral portion of wrist joint • Ulnar notch of radius • slight depression at mediodistal end; area of articulation with ulna

5. Bones and Joints There are 15 bones that form connections from the end of the forearm to the hand. The wrist itself contains eight small bones, called carpal bones. These bones are grouped in two rows across the wrist. The proximal row is where the wrist creases when you bend it. Beginning with the thumb-side of the wrist, the proximal row of carpal bones is made up of the scaphoid, lunate, and triquetrum. The second row of carpal bones, called the distal row, meets the proximal row a little further toward the fingers. The distal row is made up of the trapezium, trapezoid, capitate, hamate, and pisiform bones. The proximal row of carpal bones connects the two bones of the forearm, the radius and the ulna, to the bones of the hand. The bones of the hand are called the metacarpal bones. These are the long bones that lie within the palm of the hand. The metacarpals attach to the phalanges, which are the bones in the fingers and thumb.

6. WRIST Carpals • 1. Scaphoid • 2. Lunate • 3. Triquetrum • 4. Pisiform • 5. Trapezium • 6. Trapezoid • 7. Capitate • 8. Hamate

7. WRIST • Metacarpal bones: Nambered 1-5 (thumb side is #1) • Phalangeal bones: Fingers numbered 1-5 (thumb is #1) Proximal Middle (intermediate) Distal

8. Joints • Distal interphalangeal joint (DIP) • Proximal interphalangeal joint (PIP) • Metacarpo-phalangeal joint (MP)

9. Joint and capsule Synovial Joint: Joints where the articulating bones are separated by a fluid-containing joint cavity. Allows freedom of movement. Articular Capsule: Fibrous Capsule Synovial Membrane Joint Cavity Articular cartilage

10. ORIGIN: Attachment of a muscle tendon to the stationary bone. INSERTION: Attachment of the other muscle tendon to the movable bone. ACTION: The movement that occurs at the joint due to muscle contraction.

11. EXTENSOR MUSCLES

12. ORGIN, INSERTION & ACTION OF EXTENSOR MUSCLES Extensor carpiradialislongus: • Extensor carpiradialisbrevis: O: supracondylar ridge of humerus I: base of 2nd metacarpal A: wrist extension, radial deviation O: lateral epicondyle of humerus I: base of 3rd metacarpal A: wrist extension Extensor digitorum: • Extensor carpiulnaris: O: lateral epicondyle of the humerus I: base of distal phalanx of the 2nd-5th fingers A: extends all 3 joints of the fingers O: lateral epicondyle of humerus I: medial side of base of 5th metacarpal A: extends & adducts wrist

13. EXTENSOR MUSCLES CONT. Extensor digitiminimi: O: lateral epicondyle of humerus I: base of distal phalanx of 5th finger A: extends all joints of 5th finger • Extensor pollicisbrevis: O: posterior distal radius I: base of the proximal phalanx of pollex A: extends MP joint of thumb Extensor pollicislongus: O: middle posterior ulna & interosseous membrane I: base of distal phalanx of pollex A: extends MP & IP joints of the thumb

14. FLEXOR MUSCLES

15. ORGIN, INSERTION & ACTION OF FLEXOR MUSCLES • Flexor carpiradialis: O: medial epicondyle of the humerus I: base of 2nd & 3rd metacarpals A: wrist flexion, radial deviation • Flexor carpiulnaris: O: medial epicondyle of humerus I: pisiform & base of 5th metacarpal A: wrist flexion , ulnar deviation • Flexor digitorumsuperficialis: O: common flexor tendon, coronoid process & radius I: sides of the middle phalanx of the 4 fingers A: flexes MP & PIP joints of the fingers

16. FLEXOR MUSCLES CONT. Flexor digitorumprofundus: O: upper ¾ of ulna I: distal phalanx of the 4 fingers (2-5) A: flexes all 3 joints of the fingers Flexor pollicislongus: O: radius, anterior surface I: distal phalanx of pollex A: flexes all joints of the pollex or thumb Abductor pollicislongus: O: post. radius , interosseous membrane, middle ulna I: base of the 1st metacarpal A: abducts pollex Palmaris longus: O: medial epicondyle of humerus I: palmar fascia A: assistive in wrist flexion

17. Ligaments Tendons and Sheaths • Articular Ligaments • Fibrous dense regular connective tissue. • Connect bones to other bones. • They act as mechanical reinforcements. • Within synovial joints, act as a stabilizer to prevent excessive or undesirable motion. • Tendons and aponeurosis • Tendon – ropelike connection anchoring muscle to the connective tissue covering of a skeletal element (bone or cartilage) • Aponeurosis – sheetlike tendon • Durable, withstand abrasion of rough bony projections, and relatively small size conserve space. • Sheaths • An elongated/flattened sac, lined with synovial fluid, that wraps completely around a tendon subjected to friction. • They are common where several tendons are crowded together within narrow canals, ie wrist.

18. Ligaments and sheaths PalmarAponeurosis Flexor retinaculum – anterior Extensor retinaculum – posterior Commom flexor sheath

19. Tendons • Anterior: • Palmaris longus • Flexor carpilongus • Flexor retinaculum • Palmaraponeurosis • Posterior: • Extensor carpiulnaris • Extensor digitorum • Extensor pollicisbrevis • Extensor longus • Extensor retinaculum • Flexor carpiulnaris Posterior View Anterior View

20. Arteries • Two arteries enter the hand: • Ulnar Artery • Radial Artery • Together, the branches of these arteries form two arterial arches: • Superficial palmar arch • Deep palmar arch • Branching distally off superficial palmar arch: • Common palmar digitals Palmar View

21. VeinsDorsal view The veins of the upper extremity are divided into two sets, superficial and deep; the two sets anastomose frequently with each other. Cephalic Vein Basilic Vein Superficial dorsal venous arch Deep dorsal venous arch Dorsal View

22. Nerves • Ulnar Nerve • Radial Nerve • Median Nerve Palmar View

23. CutaneousInnervation Palmarcutaneous branch Ulnar, Radial, Median Dorsalcutaneous branch Ulnar, Radial

24. Veins Arteries and Nerve Summary

25. Innervations

26. Innervations

27. Surface AnatomyCompartments and Spaces

28. Surface Anatomy

29. Surface Anatomy

30. Surface Anatomy

31. Carpal Tunnel Syndrome • Condition caused by compression or stretching of the medial nerve. • Common disorder with people whose occupation require a great deal of wrist flexion or prolonged extension Writers Typists Pianists Computer professions

32. Carpal tunnel syndromeSymptoms • Needles and pins sensation to the index and middle finger of the wrist. • Pain in the middle area of the wrist, swelling of wrist, • Numbness or tingling in index and middle fingers, • Loss of function of hand in severe cases.

33. Carpal tunnel syndromeCures • Splints applied to dorsiflex the wrist occasionally help keep the wrist in a resting position. • In this position, the carpal tunnel is as big as it can be, so the nerve has as much room as possible inside the carpal tunnel. • Cortisone injections may help • Surgery to strip away build-up adhesive tissue may be required. • This condition can recur even after treatment and tends to worsen in the evening and night.