Anatomy of Upper Limb Flashcards
What does pectoral gridle consist of
Clavicle and Scapula
3 Segments of upper limb
Arm proper
Forearm
Hand
What bones do you find in your hand
8 carpal bones in the hand
5 metacarpals in the palm
14 phalanges in the digits
Bones of forearm and arm proper
Forearm - radius nad ulna
Arm proper - humerus
Articulation of clavicle
Articulates laterally with the acromion of the scapula = acromioclavicular joint
Articulates medially with the manubrium of the sternum and 1st rib = sternoclavicular joint
3 processes of the scapula
Acromian
Coracoid Process
Spine
What is ths spinous process of scapula divided into
Supraspinous fossa
Intraspinous fossa
How does scapula articulate with head of humerus
Glanoid cavity - forms the glenohumeral joint
Components of proximal end of humerus
Greater and lesser tubercle
Head
Neck
Shaft
What is the glenohumeral joint
Ball and socket joint
Synovial
Multi-axial
Ligaments and tendons of the sholder joint
Coracohumeral ligament Glenohumeral ligament Transverse humeral ligament Tendom of long head of biceps Rotator cuff muscles and their tendons
Whic parts of the distal humerous articulate with the radius and the ulnar
Capitulum: articulates with the head of the radius
Trochlear – pulley shaped structure, articulates with ulnar
What is the coronoid fossa and its function
Just superior to trochlear = the coronoid fossa.
When the elbow is flexed, a bony process on the ulnar will move into this fossa.
What are the medial ad lateral epicondyles
sites of attachment for muscles and ligaments around the elbow joint
What is located posteriorly on the distal humerus and what is its function
- Olecranon fossa which will house the olecranon process of the ulnar during extension of the elbow
What are the three articulations of the elbw joiunt
Humerus and ulnar
Humerus and radius
Radius and ulnar
Where does pronation and supination of the forearm occur
Proximal radioulnar joint
What ligament supports flexion and extension
collateral ligaments
How does pronation and supination occur
Distally the ulnar notch of the radius slides anteriorly over the convex surface of the head of the ulna
Bones held together during this movement by the interosseous membrane
The articular disc at the distal radio-ulnar joint
Which side of the wrist articulation os convex and concave
Distal end of the radius and the articular disc overlying the distal end of the ulna
Concave
Scaphoid, lunate and triquetrum
Convex
What is the axilla
Gateway to the upper limb – between the neck and arm
Irregular shaped pyramidal shaped space that has
-An inlet/apex that is continuous with the neck
-Skin of the armpit forms the floor
All major structures passing into and out of the upper limb pass through the axilla
What is the cubital fossa
Triangular shaped depression formed by muscles anterior to the elbow joint
A major blood vessel and a major nerve pass through this region, passing from the arm to the forearm
What is the carpal tunnel
Gateway to the palm of the hand
Formed by the carpal bones and a thick band of connective tissue
Important nerve and all the long flexor tendons from the forearm to the digits pass through
Muscles of the rotator cuff
Subscapularis
Supraspinatus
Infraspinatus
Teres minor
Attachment and function of deltoid
Attaches the scapula and clavicle to the humerus
Abductor of the arm (beyond the initial 15° carried out by supraspinatus)
Anterior fibres assist arm flexion
Posterior fibres assist arm extension
Attachment and funciton of the trapezius
Attaches the scapula and clavicle to the trunk
Elevates the scapula
Rotates the scapula allowing full abduction of the upper arm
What is the function of lavator scapulae, rhomboid minor and thomboid major
Levator scapulae
Elevates the scapula
Rhomboid minor & rhomboid major
Elevates and retract the scapula
Muscles of the pectoral region and their function
Clavicular head - Flex the arm from an extended position
Sternocostal head - Extend the arm from a flexed position
Pectoralis major - Adducts arm, Medially rotates humerus
Pectoralis minor- Depression of scapula
Serratus anterior - Rotation of scapula and protraction of the scapula
Subcalvius - stabilised the calvicle
Function of subscapularis
Medial rotation
of humerus
Function of teres major
Medial rotation and extension of arm
Function of latissimus dorsi
Adduction, medial rotation and extension of arm
Functions of biceps brachii
Flexor and supinator of the forearm, weak flexor of humerus
Brachialis function
Flexor of forearm
Function of coracobrachialis
Flexor and adductor of humerus
Function of triceps brachii
Extensor of the forearm at the elbow joint
Also extension of the arm at the shoulder joint and can assist adduction of the arm
What is the anterior compartment of the forearm innervated by
All innervated by the median nerve
Except for 2 muscles that are innervated by the ulnar nerve:
Flexor carpi ulnaris
Medial half of flexor digitorum profundus
Superficial muscle layer of anterior forearm and their functions
Flexi carpi ulnaris
- Strong wrist flexor
- Adductor of the wrist
Palmaris longus
- Wrist flexor
- Role in gripping
Flexor carpi radialis
- Powerful wrist flexor
- Abductor of the wrist
Pronator teres
-Pronation
Muscles of Intermediate layer of ant. forearm and their function
Flexor digitorum superficialis
- Wrist flexor
- Flexes the fingers
- Metacarpophalangeal joints
- Proximal interphalangeal joints
Muscles of deep layer of anterior forearm
Flexor digitorum profundus
- Wrist flexor
- Flexes the fingers
- Distal and proximal interphalangeal joints
- Metacarpophalangeal joints
Flexor pollicis longus
-Flexor of the thumb
Pronator quadratus
-Pronation
What innervates the posterior compartemnt of forearm
All innervated by the radial nerve (or branches of it)
Superficial Muscle layer of posterior forearm
Brachioradialis
Accessory flexor of the elbow
Most efficient in the mid-pronated position
Extensor carpi radialis longus
Extends the wrist
Abducts the wrist
Extensor carpi radialis brevis
Extends the wrist
Abducts the wrist
Extensor digitorum
Extends the fingers
Can extend the wrist
Extensor digiti minimi
Extends the little finger
Extensor carpi ulnaris
Extends the wrist
Adducts the wrist
Anconeus
Accessory extensor of elbow
Abducts ulnar during pronation
Muscles of the deep layer of the psoterior forearm
Supinator
-Supination
Abductor pollicis longus
- Abduct the thumb
- Accessory extensor of the thumb
Extensor pollicis brevis
- Extends the thumb
- Metacarpophalangeal joint
- Carpometacarpal joint
Extensor pollicis longus
- Extends the thumb
- Interphalangeal joint
- Metacarpophalangeal joint
- Carpometacarpal joint
Extensor indicis
-Extends the index finger
What restricts movement of the metacarpals and fingers
2nd – 4th metacarpophalangeal joints are joined by deep transverse ligaments that restrict movement of the metacarpals and fingers.
What is the function of the palmasris brevis
Improves grip
What are the interossei muscles
Dorsal interossei x4
Abductors of fingers
Palmar interossei x3/4
Adductors of fingers
Contribute to extension and flexion of the fingers
What is the function of lumbricals
Lumbricals x 4
Flex metacarpophalangeal joints
Extend interphalangeal joints
Function of the adductir poillicis
Powerful adductor of the thumb
Opposes thumb during gripping
What are the thenar muscles and what are their functions
Opponens pollicis
Thumb opposition, specifically medial rotation of thumb
Abductor pollicis brevis
Abducts the thumb
Flexor pollicis brevis
Flexes the thumb
What are the hypothenar msucles and their functions
Opponens digiti minimi
Opposition of the little finger, specifically by lateral rotation of metacarpal 5
Abductor digiti minimi
Principle abductor of the little finger
Flexor digiti minimi brevis
Flexes the little finger
What provides innervation to the hands
Supplied by the ulnar, median and radial nerves
Ulnar nerve innervates all the intrinsic muscles of the hand , except for the 3 thenar muscles and two most lateral lumbricals which are supplied by the median nerve
What is the purpose of the musculocutaneous nerve
Motor to all muscles in the anterior compartment of the arm
Purpose of median nerve
Motor to :
-All muscles in the anterior compartment of the forearm
-Except flexor carpi ulnaris and medial half
of flexor digitorum profundus
-Three thenar muscles and two most lateral lumbricals
puspose of ulnar nerve
Motor to:
-Flexor carpi ulnaris and medial half of flexor digitorum profundus in the anterior compartment of the forearm
-All intrinsic muscles of the hand
-Except three thenar muscles and two
most lateral lumbricals
Prpose of axillary nerve
Motor to deltoid and teres minor
Purpose of radial nerve
Motor to all muscles in the posterior compartment of the arm and forearm