Arm - Anatomy Flashcards
What are the four components of the upper limb
Pectoral Gridle (shoulder)
The arm
The forearm
Hand
What does the pectoral gridle refer to
Clavicle
Scapula
Muscles that attach to these bones
Name the four joints of the upper limb
Glenohumeral joint
Elbow joint
Proximal and distal radioulnar joint
Radiocarpal joint
What is the glenohumeral joint
Shoulder joint
Synovial ball and socket joint
Formed by the articulation between the scapula and proximal humerus
Highly mobile
What is the elbow joint
Synovial hinge joint
Formed by articulations of the distal humerus with the ulna and radius
Allows for flexion and extension
What are the proximal and distal radioulnar joints
Synovial joints between the radius and ulnar
Allow for pronation and supination
What is the radiocarpal joint
Wrist joint
Synovial joint
Formed by the articulations between the distal radius and two carpal bones
Allows for flexion, extension, abduction and adduction
Define protraction
Anterior movement of the scapula
Reach arm out to push open a door
Define retraction
Posterior movement of the scapula
Squaring of the shoulders
What are the possible movements of the scapula
Protraction, retraction, elevation, depression and rotation
What are the possible movements of the shoulder joint
Flexion, extension, abduction, adduction, medial (internal) rotation, lateral (external) rotation and circumduction
What are the possible movements of the elbow joint
Flexion and extension
What are the possible movements of the radioulnar joint
Pronation (palm down), supination (palm up)
What are the possible movements of the wrist joint
Flexion, extension, abduction and adduction
What are the possible movements of the fingers
Flexion, extension, adduction, abduction
What is the shape of the clavicle
S-shaped
Slender
Where and with what does the clavicle articulate
Sternum at medial end - sternoclavicular notch
Acromion of the sternum at lateral end - acromioclavicular joint
What is the key purpose of the clavicle
Holds the limbs away from the trunk so it can move easily
What is the posterior surface ridge called on the scapula
Spine
What does the lateral end of the spine expand to form on the scapula
Acromion
What makes up the pectoral girdle
Clavicle
Scapula
Attached muscles
Name the shallow fossa on the lateral aspect of the scapula
Glenoid fossa
How is the range of movement increased at the shoulder
By the glenoid fossa being shallow and a poor fit for the humerus
What is the small projection superior of the glenoid fossa called
Supraglenoid tubercule
What is the small projection inferior of the glenoid fossa called
Infraglenoid tubercule
Where is the anatomical neck of the humerus
The groove of the head of the humerus
Where is the surgical neck of the humerus
Distal to the tubercules where the bone become narrow and continuous with the shaft
Define elevation
Shrugging shoulders
Define depression
Lowering the shoulders
Define rotation
Tilts the glenoid fossa cranially to aid elevation of the upper limb
For every 2 degrees of abduction of the shoulder
Scapula rotates 1 degrees
What is the key muscle involved in protraction of the scapula
Serratus anterior
What are the two large superficial muscles of the posterior pectoral girdle
Trapezius
Latissimus dorsi
Where does the latissimus dorsi connect
Anterior aspect of the proximal humerus
NOT scapula
What are the names of the three smaller and deeper muscles of pectoral girdle
Levator scapulae
Rhomboid major
Rhomboid minor
Where do the three smaller and deeper muscles of the pectoral girdle attach
Medial border of the scapula to the vertebral column
What movement is produced by the trapezius
Movement of scapula
Upper part - elevates
Middle part - retracts
Lower part - depresses
Rotates the scapula
What movement is produced by the latissimus dorsi
Extends, adducts and medially rotates the humerus
What movement is produces by the levator scapulae
Elevates the scapula
What movement is produced by the rhomboid major
Retracts the scapula
What movement is produced by the rhomboid minor
Retracts the scapula
Where does the trapezius attach (origin)
Skull, cervical and thoracic vertebrae
Where does the trapezius attach (insertion)
Clavicle and scapula (spine and acromion)
Where does the latissimus dorsi attach (origin)
Lower thoracic vertebrae
Where does the latissimus dorsi attach (insertion)
Humerus - upper anterior
Where does the levator scapulae attach (origin)
Upper cervical vertebrae
Where does the levator scapulae attach (insertion)
Scapula - medial border
Where does the rhomboid minor attach (origin)
C7 and T1
Where does the rhomboid minor attach (insertion)
Scapula - medial border
Where does the rhomboid major attach (origin)
Thoracic vertebrae
Where does the rhomboid major attach (insertion)
Scapula - medial border
What is the trapezius innervated by
11th cranial nerve - accessory nerve (more specifically its spinal root)
What is the latissimus dorsi innervated by
Thoracodorsal nerve (branch of the brachial plexus)
What are the six muscles which attach the scapula to the humerus
Deltoid
Supraspinatus
Infraspinatus
Subscapularis
Teres major
Teres minor
Which muscles part of the six muscles which attach the scapula to the humerus does not lie deep to the posterior scapular muscles (latissimus dorsi and trapezius)
Deltoid
What does the rotator cuff provide
Vital stability to the shoulder joint
What does the deltoid attach the humerus to
Attaches humerus to lateral part of the clavicle and to the spine of the scapula
What movement can the deltoid not initiate
The first 20 degrees of abduction
What movements can the deltoid do
Abduction
Flexion (anterior fibres)
Extension (posterior fibres)
What is the deltoid innervated by
Axillary nerve
Where does the teres major arise from and attach
Arise from posterior aspect of the scapula
Inserts into the anterior aspect of the humerus
What movements do the teres major provide
Medial rotation
Adduction
What are the muscles of the rotator cuff
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Where does the rotator cuff muscles attach
Scapula to the tubercules of the humerus
Which muscles of the rotator cuff originate from the posterior surface of the scapula and insert into the greater tubercule
Supraspinatus
Infraspinatus
Teres minor
Supraspinatus
Infraspinatus
Teres minor
Their tendons fuse with what that surrounds the shoulder joint
Fibrous capsule
Where is the quadrilateral space
Above - teres minor
Below - teres major
Medial - long head triceps
Lateral - surgical neck of the humerus
What travels through the quadrilateral space
Axillary nerve
Enters the posterior scapula region and innervate deltoid and teres minor
Where does the subscapularis originate
Originate - anterior surface of scapula
What is the action of the deltoid at the shoulder joint
Abduction beyond approx. 20 degrees
Where is the origin of the deltoid
Spine and acromion (plus clavicle)
Where is the insertion on the humerus of the deltoid
Deltoid tuberosity
What is the teres major action at the shoulder joint
Medial rotation
Adduction
Where is the teres major origin at the scapula
Posterior surface, inferior part of the lateral border
Where does the teres major insert on the humerus
Anterior humerus
What is the action of the supraspinatus at the shoulder joint
First 20 degrees of abduction
Where is the origin of the supraspinatus from the scapula
Supraspinous fossa
Where is the insertion of the supraspinatus on the humerus
Greater tubercle - superior facet
What is the action on the infraspinatus on the shoulder joint
Lateral rotation
Where is the origin of the infraspinatus from the scapula
Infraspinatus fossa
Where is the insertion on the humerus of the infraspinatus
Greater tubercle - middle facet
What is the action of the teres minor at the shoulder joint
Lateral rotation
Where is the origin of the teres minor from the scapula
Lateral border
Where is the insertion of the teres minor on the humerus
Greater tubercle - inferior facet
What is the action of the subscapularis at the shoulder joint
Medial rotation
What is the origin of the subscapularis from the scapula
Subscapular fossa
What is the insertion of the subscapularis on the humerus
Lesser tubercle
Why is the supraspinatus clinically important
Travels from the supraspinous fossa to the greater tubercle it travels under the acromion
Tendon can become pinched - impingement
How does the rotator cuff provide stability
Contraction holds the head of the humerus in the shallow glenoid
Tendons fuse with the capsule of the shoulder joint
What is the rim of the fibrocartilage around the margin of the glenoid fossa
Glenoid fossa
What is the purpose of the glenoid fossa
Deepens the shallow fossa and aids stability
What is the capsule (shoulder) reinforced by
Ligaments
What structure which lies in the anterior arm reinforces the shoulder joint
Tendon of bicep brachii