Upper Limb I Flashcards
Three types of joints
Fibrous, cartilagenous, synovial
Fibrous joints
permit little or no movement, consist of two bones joined by dense CT, ex: sutures of the skull
Cartilagenous joints
permit slight amounts of movement, consist of two bones joined by fibrocartilaginous disks between articular surfaces, ex: intervertebral joints
Synovial joints
permit the greatest degree of movement, consist of two bones separated by a CT capsule and associated ligaments, ex: shoulder, knee
Components of a synovial joint
Synovial cavity, articular capsule, articular cartilage, synovial membrane, intima, synovial fluid, subintima, extrinsic ligaments, intrinsic ligaments, bones, muscles, tendons
Joints of the shoulder
Acromioclavicular joint, glenohumeral joint, sternoclavicular joint, and scapulothoracic joint
Glenohumeral joint
Articulation: head of the humerus and the glenoid fossa of the scapula
Movements: arm flexion, extension, abduction, adduction, internal rotation, external rotation
Sternoclavicular joint
Articulation: clavicle and sternum
Movements: relatively immobile, allow for gliding type of motion
Acromioclavicular joint
Articulation: clavicle and acromion process
Movements: relatively immobile, allow for a gliding motion
Scapulothoracic “joint”
Articulation: anterior surface of scapula and posterior/lateral thoracic wall
Movements: more of a functional joint, scapula elevation, depression, protraction, retraction, upward, downward
Static stabilizers of the glenohumeral joint
Capsule and its associated ligaments
Dynamic stabilizers of the glenohumeral joint
The muscles of the rotator cuff
Muscles of the rotator cuff
Supraspinatus, infraspinatus, subscapularis, teres minor
Supraspinatus
Movements: initiates and assists with abducting the arm
Nerve: suprascapular nerve
Infraspinatus
Movements: external rotation, abduction, adduction of the arm
Nerve: suprascapular
Subscapularis
Movements: internal rotation of the arm
Nerves: upper and lower subscapularis nerves
Teres minor
Movements: external rotation and adduction of the arm
Nerve: axillary nerve
Ligaments of the glenohumeral joint
Glenoid labrum, glenohumeral ligaments
Ligaments of the AC joint
Acromioclavicular ligament and coracoclavicular ligaments
Shoulder dislocation
Disarticulation of the head of the humerus from the glenoid
Shoulder separation
Disarticulation of the clavicle and acromion, can be classified as one of three grades (I-III)
Compartments of the arm
Anterior and posterior compartments, separated by the medial and lateral intermuscular septum
Anterior compartment of the arm
Muscles: biceps brachii, brachialis, coracobrachialis
Movements: flexion of arm and forearm, supination of the hand
Nerve: musculocutaneous nerve
Blood supply: brachial artery
Biceps brachii
Movements: flexion of arm and forearm, supination of hand
Nerve: musculocutaneous
Brachialis
Movement: flexion of forearm
Nerve: musculocutaneous
Coracobrachialis
Movement: flexes arm
Nerve: musculocutaneous
Posterior compartment of the arm
Muscle: triceps brachii
Movements: extend the arm and forearm
Nerve: radial nerve
Blood: deep brachial artery
Triceps brachii
Movement: extension of arm and forearm
Nerve: radial
Forearm
Bones: radius and ulna
Joints: elbow and wrist
Elbow joint
Articulation: trochlear notch of the ulna with the trochlea of the humerus, and the head of the radius with the capitulum of the humerus
Movements: flexion and extension of the forearm
Wrist/radiocarpal joint
Articulation: distal radius and proximal carpal bones (scaphoid and lunate)
Movements: flexion, extension, abduction, adduction of the hand
Proximal and distal radioulnar joints
Articulation: radius and ulna
Movements: pronation and supination of the hand
Compartments of the forearm
Anterior and posterior, separated by the interosseous membrane between the radius and ulna and the medial and lateral intermuscular septum
Anterior compartment of the forearm
Muscles: pronator teres, flexor carpi ulnaris, palmaris longus, flexor digitorum superficialis, flexor pollicis longus, flexor digitorum profundus, pronator quandratus
Movements: flexion of the wrist and digits, pronation, abduction, adduction of the hand
Nerves: median nerve (for all but flexor carpi ulnaris and the medial half of flexor digitorum profundus), ulnar nerve (for the two mentioned before)
Blood: radial and ulnar arteries
Posterior compartment of the forearm
Muscles: extensor carpi ulnaris, extensor carpi radialis longus and brevis, extensor digiti minimi, extensor indicis, abductor pollicis longus, extensor pollicis longus, extensor pollicis brevis and supinator
Movements: extension of the wrist and digits, supination of the hand, extension and abduction of the thumb
Nerve: radial nerve
Blood: radial and ulnar arteries
Pronator teres
Movement: pronation of the hand
Nerve: median
Flexor carpi radialis
Movements: flexion and abduction of the hand
Nerve: Median
Flexor carpi ulnaris
Movement: flexion and adduction of the hand
Nerve: Ulnar
Palmaris longus
Movement: flexion of the hand
Nerve: Median
Flexor digitorum superficialis
Movements: flexion of hand, MP and PIP joints
Nerve: median
Flexor pollicis longus
Movement: flexion of thumb
Nerve: median (anterior interosseous)
Flexor digitorum profundus
Movement: flexion of hand, MP, PIP, and DIP joints
Nerve: median (to medial half), ulnar (to ulnar half)
Pronator quadratus
Movement: pronation of hand
Nerve: median
Extensor carpi ulnaris
Movement: extension and adduction of hand
Nerve: radial
Extensor carpi radialis longus and brevis
Movements: extension and abduction of hand
Nerve: radial
Extensor digitorum
Movement: extension of hand and fingers
Nerve: radial
Extensor digiti minimi
Movement: extension of little finger
Nerve: radial
Extensor indicis
Movement: extension of index finger
Nerve: radial
Abductor pollicis longus
Movement: abduction of thumb
Nerve: radial
Extensor pollicis longus
Movement: extension of thumb
Nerve: radial
Extensor pollicis brevis
Movement: extension of thumb
Nerve: radial
Supinator
Movement: supination of hand
Nerve: radial
Joints of the wrist, hand and digits
Radiocarpal joint, carpometacarpal joints, metacarpophalangeal joints, proximal and distal interphalangeal joints
Carpometacarpal joints
Articulation: proximal metacarpals and distal carpal bones
Movement: relatively immovable
Metacarpophalangeal joints
Articulation: distal metacarpals and proximal phalanx
Movements: flexion, extension, abduction, adduction of the digits
Proximal and distal interphalangeal joints
Articulation: proximal and middle phalanx, and middle and distal phalanx of the 4 fingers
Movement: flexion and extension of middle and distal phalanx
Intrinsic muscles of the hand
Organized into superficial and deep layers, has both of its attachments in the hand
Superficial muscles of the hand
Muscles: 3 muscles that form the thenar pad at the base of the thumb (abductor pollicis brevis, flexor pollicis brevis, opponens pollicis), 3 muscles that form the hypothenar pad at the base of the little finger (abductor digiti minimi, flexor digiti minimi, opponens digiti minimi), the 4 lumbricals, adductor pollicis
Movements: flexion, opposition and abduction of the thumb, little finger, flexion of the MP joint, extension of the IP joints, adduction of the thumb,
Nerves: ulnar (all except the lateral 2 lumbricals and the 3 thenar muscles), median (previously mentioned muscles)
Blood: branches of radial and ulnar arteries via a superficial palmar arch
Deep muscles of the hand
Muscles: palmar interossei (3) and dorsal interrossei (4)
Movements: adduction and abduction of the fingers
Nerve: ulnar
Blood: branches of the radial and ulnar arteries via a deep palmar arch
Abductor pollicis brevis
Movement: abduction of the thumb
Nerve: median
Flexor pollicis brevis
Movement: flexion of the thumb
Nerve: median
Opponens pollicis
Movement: opposition of the thumb
Nerve: median
Abductor digiti minimi
Movement: abducts little finger
Nerve: ulnar
Flexor digiti minimi
Movement: flexion of the little finger
Nerve: ulnar
Opponens digiti minimi
Movement: opposition of the little finger
Nerve: ulnar
Lateral lumbricals (1-2)
Movements: flexion of MP joints, extension of IP joints
Nerve: median
Medial lumbricals (3-4)
Movements: flexion of MP joint, extension of IP joints
Nerve: ulnar
Adductor pollicis
Movement: adduction of thumb
Nerve: ulnar
Palmar interossei
Movement: adduction of fingers
Nerve: ulnar
Dorsal interossei
Movement: abduction of the fingers
Nerve: ulnar
Organization of the upper limb
Shoulder - where the upper limb attaches to the trunk (scapula, clavicle, proximal end of the humerus)
Arm - between shoulder and elbow joint (humerus)
Forearm - between elbow joint and wrist joint (ulna and radius)
Hand and digits - distal to wrist joint (carpals, metacarpals, phalanges)
Function of the upper limb
Position the hand in space for use as a mechanical and sensory tool