Upper limb Flashcards
What are the bone(s) that constitute the pectoral girdle?
Scapula and clavicle
What are the bone(s) that constitute the arm?
Humerus
What are the bone(s) that constitute the forearm?
Ulna and radius
What are the bone(s) that constitute the hand?
1) Carpal
2) Metacarpal
3) Phalanges
What are the 6 joints of the upper limb?
1) Scapulohumeral
2) Acromioclavicular
3) Sternoclavicular
4) Elbow
5) Wrist
6) Carpometacarpal
7) Interphalangeal
What are the 3 types of joints?
1) Fibrous
- fibrous tissue → no/little mvt
2) Cartilaginous
- hyaline or fibrocartilage → small amount of mvt
3) Synovial joint
- bones covered by hyaline cartilage, separated by joint cavity → greatest degree of movement
What are 3 factors that determine the stability of a synovial joint?
1) Shape & arrangement of articular surfaces
2) Ligaments
3) Muscle tone
What are 3 factors that limit movement of synovial joint?
1) Shape of bone
2) Adjacent structures
3) Ligaments (intrinsic/extrinsic)
What are the 6 types of synovial joints?
1) Gliding
2) Pivot
3) Hinge
4) Condyloid
5) Saddle
6) Ball and Socket
In a plane/gliding joint, the articular surfaces are _______, permitting bones to slide or glide over one another.
Flat
What type of synovial joint allows for uniaxial flexion and extension?
Hinge joint
Which type of synovial joint allows the greatest range of motion in multiple axes?
Ball & Socket
What is a pivot joint and what type of movement does it allow?
A central bony pivot surrounded by a ligamentous ring.
Allows for rotation
What types of movement are allowed in a condyloid joint?
1) Flexion, extension
2) Abduction, Adduction
3) Small amount of rotation
How are the bones articulated in an ellipsoid joint?
Concave surface of bone articulates with convex surface of other (u-shape)
How are the bones articulated in a saddle joint?
Articular surfaces are concavo-convex (s-shaped like saddle)
What are the borders and angles of the triangular scapula bone?
Borders:
1) Medial
2) Lateral
3) Superior
Angles
1) Superior
2) Inferior
The anterior/costal surface of the scapula forms the ___________________
Subscapular fossa
The posterior surface of the scapula is divided by the spine which laterally projects as the _________________ which articulates with the _____________.
Laterally, the _____ fossa articulates with the head of the humerus. Its superior border is marked by ____________.
Spine → Acromion process → articulate w clavicle
Laterally: Glenoid fossa
Superior: Coracoid process
- projects antero-laterally and scapular notch
What are the rotator cuff muscles and where are their origins?
From posterior surface of scapula:
1) Supraspinatus
2) Infraspinatus
3) Teres minor
From costal surface of scapula:
4) Subscapularis
What is the function of the rotator cuff muscles?
Stabilises glenohumeral joint
- Holds head of the humerus against glenoid cavity of the scapula (stability)
Other than the rotator cuff muscles, what are the other muscles acting on the scapula and what are their actions?
1) Trapezious
- elevates, retracts and depress scapula
2) Levator scapula
- elevates scapula
3) Rhomboids
- retract scapula
What are the muscle(s) that elevate the scapula?
1) Trapezious
2) Levator Scapula
What are the muscle(s) that retract the scapula?
1) Trapezious
2) Rhomboids
What are the muscle(s) that depress the scapula?
Trapezious
What are the points of attachment of the deltoid muscle?
Posterior fibres → spine of scapula
Middle fibres → acromion of scapula
Anterior fibres → clavicle
What are the functions of the deltoid and which fibres mediate which?
All arm
Anterior: (i) Flexion (ii) Medial rotation
Middle: Abduction
Posterior: (i) Extension (ii) Lateral rotation
What is the origin and insertion of the serratus anterior?
Origin: Upper 8 ribs
Insertion: Medial border of scapula
What are 2 functions of the serratus anterior?
1) Rotate scapula
2) Hold scapula against thoracic wall
What does paralysis of the serratus anterior lead to?
Winged scapula
Lesion of long thoracic nerve → weakening of serratus anterior → winging of scapula
What are the 6 scapular movements?
1-2) Elevation/Depression
3-4) Abduction/Adduction
5-6) Upward/Downward rotation
What is the shoulder joint?
Head of humerus articulates with Glenoid fossa to form the glenohumeral joint (ball and socket)
What are the 6 movements of the shoulder?
1-2) Flexion/Extension
3-4) Abduction/Adduction
5-6) Medial/Lateral rotation
7) Circumduction
What are 4 movements of the forearm?
1-2) Flexion/Extension
3-4) Supination/Pronation
What are 8 movements of the hand?
1-2) Flexion/Extension
3-4) Pronation/Supination
5-6) Radial/Ulnar deviation
7) Cylindrical grasp
8) Tip
9) Hook/snap
10) Palmar
11) Spherical grasp
12) Lateral
True or false: The deltoid is multipennate.
True.
Has posterior, middle and anterior fibres
Which nerve innervates the serratus anterior?
Long thoracic nerve
What are 2 joints formed by the humerus?
1) Glenohumeral
2) Elbow
The intertubercular groove of the humerus is formed by the _______________ on the head of the bone. This is the site of attachment for the _________________.
Intertubercular groove formed by greater and lesser tubercle on head of humerus
Site of attachment for long head of biceps tendon
Where does the deltoid muscle attach to on the humerus?
Deltoid tuberosity
Where is the radial groove of the humerus and what is its function?
Posterior diaphysis for radial nerve
Which nerve may be lesioned after a fracture at the surgical neck of a humerus?
Axillary nerve
Which nerve may be lesioned after a fracture at the shaft of a humerus?
Radial nerve
Which nerve may be lesioned after a fracture at the supracondylar ridge of a humerus?
Median nerve
Which nerve may be lesioned after a fracture at the medial epicondyle of a humerus?
Ulnar nerve
The glenoid cavity is deepened by the _________________.
Glenoid labrum (fibrocartilaginous ring)
What is the difference between the surgical and anatomical neck of the humerus?
Surgical: between head and greater tuberosity
Anatomical: below greater and lesser tuberosity
What are the articular surfaces of the glenohumeral joint covered by?
Hyaline cartilage
The humeral head is held in the glenoid cavity by the _________________.
Rotator cuff muscles:
1) Supraspinatus
2) Infraspinatus
3) Teres minor
4) Subscapularis
What are the 4 ligaments associated with the shoulder joint?
Strengthen joint capsule:
1) Glenohumeral (anterior)
2) Coracohumeral (superior)
3) Transverse humeral
Prevents superior displacement of head of humerus:
4) Coracoacromial
A fibrous capsule lined by synovial membrane surrounds the shoulder joint and is attached to __________________________.
Margin of glenoid cavity and anatomical neck of humerus
What muscle(s) facilitate shoulder flexion?
1) Pectoralis major
2) Anterior deltoid
3) Biceps
4) Coracobrachialis
What muscle(s) facilitate shoulder extension?
1) Posterior deltoid
2) Latissimus dorsi
What muscle(s) facilitate shoulder abduction?
1) Supraspinatus
2) Middle deltoid
What muscle(s) facilitate shoulder adduction?
1) Pectoralis major
2) Latissimus dorsi
What muscle(s) facilitate lateral rotation of the shoulder?
Infraspinatus
What muscle(s) facilitate medial rotation of the shoulder?
Subscapularis
How is the arm raised vertically 180 degrees?
1) Scapulothoracic upward rotation → 60°
- by Serratus anterior
2) Glenohumeral abduction → 120°
i) Supraspinatus initiates
ii) Middle fibres of deltoid abducts
What is Hilton’s Law?
The nerves supplying a joint also supply the muscles moving the joint and the skins covering their attachment (myotome=dermatome)
Describe the innervation of the shoulder joint.
Somatic pain:
1) Suprascapular nerve
2) Axillary nerve
(Joints also transmit proprioception)
What is the most commonly dislocated joint and why?
Shoulder joint
i) wide range of movement
ii) inferior aspect unprotected by muscles
Which nerve may be injured in an anterior dislocation of the shoulder?
Axillary nerve
What are 3 factors influencing the stability of the shoulder joint?
1) Tonus of rotator cuff muscle holds the head of humerus in the glenoid cavity
2) Ligament
3) Coracobrachialis, long/short head of biceps resist downward dislocation
Which direction is shoulder dislocation is more common?
Anterior
What is the “stabilising bone” of the elbow?
Ulna
What are 4 components of the ulna?
1) Olecranon
2) Trochlea notch
3) Coronoid process
4) Distal head
The styloid process of the humerus is (smaller/larger) than the ulnar styloid process.
Larger
What type of joint is the elbow joint?
Hinge
What are the 3 articulations of the elbow joint?
1) Trochlea of humerus + Trochlear notch of ulna
2) Capitulum of humerus + Upper surface of radial head
3) Head of radius + Radial notch of ulna
The elbow joint is surrounded by a fibrous capsule which is weak ________________________ allowing for _________________.
Weak anterior and posteriorly → allowing for flexion and extension
What are the ligaments of the elbow joint?
Strengthen elbow joint:
1) Medial and lateral collateral
Hold proximal radio-ulnar joint (radial head against radial notch):
2) Annular ligament (encircles radial head)
What are the nerves of the elbow joint?
1) Musculocutaneous
2) Radial
3) Ulnar
At which joint(s) does elbow flexion and extension occur?
Humero-radial and Humero-ulnar joints
At which joint(s) does elbow pronation and supination occur?
Proximal radio-ulnar joint
What muscle(s) facilitate elbow flexion?
1) Biceps
2) Brachialis
3) Brachioradialis
What muscle(s) facilitate elbow extension?
1) Triceps
2) Anconeus
What muscle(s) facilitate elbow pronation?
1) Pronator teres
2) Pronator quadratus
What muscle(s) facilitate elbow supination?
1) Biceps
2) Supinator
What is a subluxation?
Incomplete or partial dislocation of a joint or organ.
What is the usual consequence of a subluxation of the the radial head from the annular ligament?
Posterior dislocation of the elbow joint
What is the most likely dislocation of a fall with elbows flexed?
Posterior dislocation
What is the carrying angle?
Angle formed by the axes of the arm and forearm when the forearm is in full extension and supination
(Internal angle of deviation of ulna from long axis of humerus)
The carrying angle is generally (wider/narrower) in females.
Wider
What is the function of the carrying angle?
Allows forearms to clear the hips in swinging movements when carrying objects.
In the hand there are:
__ carpal bones
__ metacarpal bones
__ proximal phalanges
__ middle phalanges
__ distal phalanges
In the hand there are:
8 carpal bones
5 metacarpal bones
5 proximal phalanges
4 middle phalanges
5 distal phalanges
Which type of joint is the wrist joint?
Ellipsoid
What are the articulating surfaces of the wrist joint?
Distal end of radius + articular disc of distal radio-ulnar joint + proximal carpal bones (scaphoid, lunate, triquetrum)
What are the 3 nerves that innervate the wrist joint?
1) Median
2) Radial
3) Ulnar
The fibrous capsule surrounding the wrist joint is strengthened by which ligaments?
1) Palmar radiocarpal
2) Dorsal radiocarpal
3) Ulnar collateral
4) Radial collateral
The radial collateral ligament runs from the _______ to the _______ and ___________.
Radius to scaphoid and trapezium
The ulnar collateral ligament runs from the _______ to the _______ and ___________.
Ulna to triquetrum and pisiform
What are the 8 movements of the wrist joint?
1-2) Flexion/Extension
3-4) Pronation/Supination
5-6) Abduction/Adduction
7-8) Radial/Ulnar deviation
What muscle(s) facilitate wrist flexion?
1) Flexor carpi radialis
2) Flexor carpi ulnaris