Hand and Wrist Joint Tana Pearson Galina Nesenchuk Vira Iatchenko 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 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 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 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 thumbside 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. WRIST • • • • • • • • Carpals 1. Scaphoid 2. Lunate 3. Triquetrum 4. Pisiform 5. Trapezium 6. Trapezoid 7. Capitate 8. Hamate WRIST • Metacarpal bones: Nambered 1-5 (thumb side is #1) • Phalangeal bones: Fingers numbered 1-5 (thumb is #1) Proximal Middle (intermediate) Distal Joints • Distal interphalangeal joint (DIP) • Proximal interphalangeal joint (PIP) • Metacarpo-phalangeal joint (MP) Joint and capsule Synovial Joint: Joints where the articulating bones are separated by a fluidcontaining joint cavity. Allows freedom of movement. Articular Capsule: Fibrous Capsule Synovial Membrane Joint Cavity Articular cartilage 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. EXTENSOR MUSCLES ORGIN, INSERTION & ACTION OF EXTENSOR MUSCLES Extensor carpi radialis longus: Extensor carpi radialis brevis: O: lateral epicondyle of humerus I: base of 3rd metacarpal A: wrist extension Extensor carpi ulnaris: O: lateral epicondyle of humerus I: medial side of base of 5th metacarpal A: extends & adducts wrist O: supracondylar ridge of humerus I: base of 2nd metacarpal A: wrist extension, radial deviation Extensor digitorum: O: lateral epicondyle of the humerus I: base of distal phalanx of the 2nd-5th fingers A: extends all 3 joints of the fingers EXTENSOR MUSCLES CONT. Extensor digiti minimi: O: lateral epicondyle of humerus I: base of distal phalanx of 5th finger A: extends all joints of 5th finger Extensor pollicis brevis: O: posterior distal radius I: base of the proximal phalanx of pollex A: extends MP joint of thumb Extensor pollicis longus: O: middle posterior ulna & interosseous membrane I: base of distal phalanx of pollex A: extends MP & IP joints of the thumb FLEXOR MUSCLES ORGIN, INSERTION & ACTION OF FLEXOR MUSCLES Flexor carpi radialis: O: medial epicondyle of the humerus I: base of 2nd & 3rd metacarpals A: wrist flexion, radial deviation Flexor carpi ulnaris: O: medial epicondyle of humerus I: pisiform & base of 5th metacarpal A: wrist flexion , ulnar deviation Flexor digitorum superficialis: 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 FLEXOR MUSCLES CONT. Flexor digitorum profundus: O: upper ¾ of ulna I: distal phalanx of the 4 fingers (2-5) A: flexes all 3 joints of the fingers Flexor pollicis longus: O: radius, anterior surface I: distal phalanx of pollex A: flexes all joints of the pollex or thumb Abductor pollicis longus: 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 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. Ligaments and sheaths Palmar Aponeurosis Flexor retinaculum – anterior Extensor retinaculum – posterior Commom flexor sheath Tendons Anterior: •Palmaris longus •Flexor carpi longus •Flexor retinaculum •Palmar aponeurosis Posterior: • Extensor carpi ulnaris • Extensor digitorum • Extensor pollicis brevis • Extensor longus • Extensor retinaculum • Flexor carpi ulnaris Anterior View Posterior View 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 Veins Dorsal 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 Nerves • Ulnar Nerve • Radial Nerve • Median Nerve Palmar View Cutaneous Innervation Palmar cutaneous branch Ulnar, Radial, Median Dorsal cutaneous branch Ulnar, Radial Veins Arteries and Nerve Summary Innervations Muscle Nerve Artery Flexor carpi ulnaris Ulnar nerve Ulnar artery Flexor digitorum profundus Median and ulnar nerves Ulnar Artery Flexor digitorum superficialis Median nerve Ulnar artery Palmaris longus Median nerve Ulnar artery Flexor carpi radialis Median nerve Radial and Ulnar arteries Flexor pollicis longus Median nerve Radial artery Innervations Muscle Nerve Artery Abductor pollicis longus Radial nerve Posterior interosseous artery Extensor pollicis brevis Radial nerve Posterior interosseous artery Extensor pollicis longus Radial nerve Posterior interosseous artery Extensor carpi radialis longus Radial nerve Radial artery Extensor carpi radialis brevis Radial nerve Radial artery Extensor carpi ulnaris Deep radial nerve Ulnar artery Extensor digitorum Radial nerve Recurrent interosseous artery Extensor digiti minimi Radial nerve Recurrent interosseous artery Surface Anatomy Compartments and Spaces Surface Anatomy Surface Anatomy Surface Anatomy 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 Carpal tunnel syndrome Symptoms • 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. Carpal tunnel syndrome Cures • 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.