SHOULDER AND ELBOW . Flashcards
(107 cards)
1
Q
● 20 muscles
● 3 bony articulations
● 3 soft tissue moving surface (functional joints)
● Permit the greatest mobility of any joint area found in the
body
A
Shoulder Complex
2
Q
How many hand placements
A
16,000
3
Q
only bony attachment of UE to
trunk
A
Sternoclavicular joint
4
Q
○ Manubrium
○ Right and left clavicles
○ Right and left scapulae
● Incomplete girdle (does not have bony connection
posteriorly)
A
Shoulder Girdle
5
Q
● Clavicular facet
● Sternal/jugular notch
● Facets for attachment
of the first ribs
A
Manubrium
6
Q
● Clavicular facet
● Sternal/jugular notch
● Facets for attachment
of the first ribs
A
Manubrium
7
Q
● Lateral strut to the
scapula and the
humerus.
● This increases
glenohumeral mobility
to permit greater
motion in reaching and
climbing activities.
A
Clavicle
8
Q
● a flat,
triangular-shaped
bone
● 3 sides and 3 angles
● sits against the
posterior thorax.
● Lies on the posterior
ribs
● Conforms to the
upper thorax
● Does not lie in a
pure frontal plane
A
Scapula
9
Q
Inferior angle of scapula
A
T7
10
Q
Scapular spine
A
T3
11
Q
● Dense fibrous
connective tissue rim
that surrounds the
glenoid fossa.
● Increase joint
congruence.
A
Glenoid Labrum
12
Q
● Tilted 5° upward relative
to the scapular vertebral
border.
● Teardrop or pear-shaped
appearance
● Orientation: lateral,
superior, and anterior
direction (LAS)
● (Concave)
A
Glenoid Fossa
13
Q
Head of humerus
○ Convex
○ 1/3 to ½ sphere
○ Orientation: medial,
superior, posterior
(PMS)
A
Humerus
14
Q
Angle of inclination
A
humeral head is angled at
135° to the long axis of
the humeral shaft
15
Q
Angle of torsion
A
30°
16
Q
Resting position of the humeral head in posterior rotation
relative to the distal condyles of the humerus allows the
head to be aligned in the scapular plane while
maintaining proper elbow joint alignment; this relative
position of posterior rotation =
A
Retroversion
17
Q
through which the LH
of biceps runs from
its proximal insertion
on the supraglenoid
tubercle.
A
Bicipital groove
18
Q
● Circumferential area on the
proximal humerus.
● Distal to the bicipital groove
● Common site for humeral
fractures, especially in the
elderly, when a fall occurs and
the individual lands on an
outstretched arm.
A
Surgical Neck
19
Q
are the result of
sternoclavicular and acromioclavicular joint movements.
A
Scapulothoracic motions
20
Q
responsible for the majority
of the scapular movement.
A
Sternoclavicular joint
21
Q
provides minimal movement
and acts more as a fine tuner of scapular motion than
a producer of its motion
A
Acromioclavicular joint
22
Q
● The only joint that acts as
a strut to connect the
upper extremity directly
with the axial skeleton.
● Medial end of the clavicle
connects with the
manubrium of the
sternum and the medial
first rib.
A
Sternoclavicular Joint
23
Q
● Plane synovial joint
● 3 DOF
○ Elevation/Depression
○ Abduction/Adduction
○ UR/DR
● Medial margin of the
acromion and the lateral
end of the clavicle
● Lined with fibrocartilage
A
Acromioclavicular Joint
24
Q
● no bony articulations
● False joint/pseudo joint/functional joint
● Separating the scapula from the thorax are soft tissue
structures, including a large subscapular bursa.
A
Scapulothoracic Joint
25
● Shoulder joint
● Ball-and-socket
● 3 DOF
● Little bony stability
○ Convex: Humeral
head (PMS)
○ Concave: Glenoid
fossa (small/shallow)
(LAS)
● Labrum
○ From neck of glenoid
○ To anatomic neck of
humerus
● 10 to 15 mL
● Axillary pouch
Glenohumeral Joint
26
● Ligaments and tendons blend with and reinforce the
glenohumeral joint capsule for added stability.
○ Coracohumeral ligament
○ Superior, Middle, Inferior GH ligament
Capsular Reinforcement
27
coracoid process of the
scapula → greater and
lesser tubercles of the
humerus
● where it forms a tunnel
for the tendon of the
long head of the biceps
brachii.
Coracohumeral Ligament
28
● Capsular ligaments
● From the glenoid and its
labrum, form capsular
thickenings, and attach to
the humeral neck and
lesser tubercle
Superior, Middle and Inferior GH
Ligaments
29
Support the dependent
(hanging down) arm and
limit lateral rotation in the
lower ranges of
abduction
Coracohumeral, Superior and Middle GH
Ligaments
30
● Forms a hammock-like
sling with anterior and
posterior bands around
the lower portion of the
humeral head and is part
of the axillary pouch.
● Main stabilizer of the
abducted shoulder
Inferior Glenohumeral Ligament
31
● anterior acromion →
lateral coracoid process
● osteoligamentous arch
● roof of the glenohumeral
joint
Coracoacromial Arch
32
● Contains:
○ supraspinatus muscle
and tendon,
○ long head of the
biceps tendon
○ subacromial bursa
○ superior capsule
Subacromial Space
33
● Area under the
coracoacromial
● Formed by the neck of
the scapula, the acromion
process, the rigid
coracoacromial ligament,
and the coracoid process
Supraspinatus Outlet
34
● A bursa reduces friction
between two structures.
● 8 bursae within the
shoulder area
○ Subacromial bursa
Bursae
35
● Scapular plane
glenohumeral abduction
● Occurs 30° to 40°
anterior to the frontal
plane
Scaption
36
● LH of biceps tendon
● Retained by the
coracohumeral ligament
and by the transverse
humeral ligament
Bicipital Groove
37
● They found that the early phase of abduction was
individually variable.
Scapulohumeral Rhythm
38
This early stage of motion was termed the “setting
phase.” After about ____ of abduction, a ___ ratio occurred:
For every 2° of glenohumeral motion, 1° occurred at the
scapulothoracic joint.
30°; 2:1
39
Primary scapular protractor
● “saw muscle”
● lowest five digitations is the strongest portion of the
muscle
● XXX: Medial winging of the scapula
Serratus Anterior
40
● superficial muscle of the neck
and upper back
● “Shawl” muscle or “musculus
cucullaris”
● Full abduction with scapular rot:
All fibers
○ Mid = ret
○ Upper and Lower = upward
rot.
● XXX: Lateral winging of the
scapula
○ Elevation is limited to 120
degrees (only by GH)
Trapezius
41
● connect the scapula with the vertebral column lie under the
trapezi
● XXX: scapula in protracted position
● scapula positioned farther laterally from the thoracic
spinous processes
● than the normal 6 cm from the thoracic spinous processes.
Rhomboid Major and Minor
42
● located anteriorly on the upper chest by the pectoralis
major.
● XXX: Weakness of this muscle results in reduced
strength during scapular depression and downward
rotation of the scapula against resistance.
Pectoralis Minor
43
An elevator of the scapula, an action it shares with
the upper trapezius and with the rhomboids.
● Elevation + DR
● XXX: reduced ability to elevate and downwardly
rotate the scapula.
Levator Scapulae
44
provide glenohumeral stability as well as
glenohumeral motion.
Rotator Cuff
45
● located above the spine of the scapula.
● capable of performing the total motion of abduction
without the assistance of the deltoid.
Supraspinatus
46
External rotators of the shoulder
Infraspinatus and Teres Minor
47
@ infraspiIatus fossa
InfraspinaItus
48
@ lateral border of the scapula
Teres minor
49
● located on the anterior scapula.
● IR = primary medial rotation function
● But can also flex, extend, adduct, or abduct the
glenohumeral joint
Subscapularis
50
● Lies distal to the teres minor on the lateral scapula
border
● The teres major acts in most pulling activities when the
shoulder is extended or adducted against resistance.
Teres Major
51
● A large, superficial muscle consisting of three parts: anterior,
middle, and posterior.
● The muscle covers the glenohumeral joint on all sides
except in the inferior
● Axillary region
● Comprises 40% of the mass of the scapulohumeral muscles
Deltoid
52
● This muscle is the broadest muscle of the low back and
the lateral thoracic region
● If the arms are stabilized, as in pushing down on crutch
handles or in a seated press down, the distal attachment
aids to lift the pelvis.
Latissimus Dorsi
53
● Large muscle of the chest
● Two parts
○ Clavicular
○ Sternocostal
Pectoralis Major
54
Parts of Brchial Plexus
● Roots
● Trunks
● Divisions
● Cords
● Branches
Remember: “RoTonDa CuBao”
55
● 3 individual joints
● Surrounded by 1 capsule
● Humeroulnar joint + humeroradial joint = “elbow joint”
● Proximal radioulnar joint (PRUJ)
Elbow Complex
56
holds
the head of radius in proper
relation to the ulna and
humerus
Annular ligament
57
connects
the radius and ulna, running
from the lateral side of the
ulnar tuberosity to the
radius slightly below the
radial tuberosity
Oblique cord
58
Branches of the Brachial Plexus
● Musculocutaneous
● Radial
● Median
59
Pathological conditions of the
Elbow and FA region (Acute):
● Fracture
● Strain
● Sprain
● Distraction injuries
60
Pathological conditions of the
Elbow and FA region (Chronic):
● Overuse
● Repetitive microtrauma
61
● Congruent
● Bones possesses notches, ridges, grooves that fit like
jigsaw puzzle pieces
● Stability and Function
Elbow Complex
62
● The proximal articulating bone of the elbow, a long bone with several distinct
markings on its distal end, some of which are
palpable.
Humerus
63
● Attachment site for
○ primary forearm pronator (pronator teres)
○ major stabilizing ligament (the ulnar collateral
ligament)
○ most of the wrist and finger flexor muscles
Medial epicondyle
64
● Attachment site for
○ wrist and finger/thumb extensors
○ forearm supinator.
Lateral epicondyle
65
landmark that is
palpable between
the lateral head of
the triceps
posteriorly and the
brachioradialis
muscle anteriorly
Lateral supracondylar
ridge
66
Providing a deep and stable articulating surface for the
superior ulna when the elbow is in full extension
Olecranon fossa
67
is the more
integral articulating bony
partner with the humerus
at the elbow, forming the
humeroulnar joint
Ulna
68
The distinctive posterior prominence of the superior ulna
and is the most posterior portion of the elbow when the
joint is flexed.
Olecranon process
69
● The concave ulnar trochlear
notch articulates with the
more proximal humeral
trochlea to form the medial
elbow joint.
● Also known as the semilunar
notch.
Trochlear notch
70
This large articulating
ulnar surface is divided in
the center by a prominent
trochlear or longitudinal
ridge that articulates with
the trochlear groove of its
humeral companion
Trochlear and longitudinal ridge
71
● , an attachment
site for a primary elbow
flexor muscle, the brachialis.
● Radial notch articulates with
the radius to form the
proximal radioulnar joint
Ulnar tuberosity
72
● contributes to proximal
forearm function, it plays a
more important role at the
distal radioulnar joint and
at the wrist.
Radius
73
is located just
distal to the humeral lateral condyle.
Head of Radius
74
The superior surface of the radial head has a deep
concave fovea, which articulates with the round convex
head of the humeral capitulum to form the humeroradial
joint.
Fovea
75
● Just distal to the radial head on the anterior radial
neck .
● is the attachment site for the
biceps brachii
Radial tuberosity
76
● Ginglymus
● Uniaxial hinge joint
● 1 DOF
● Flexion and extension in sagittal plane around the
frontal axis
Elbow
77
located in the olecranon
fossa, buffering the
locking of the elbow when
it moves into full
extension.
Olecranon bursa and fossa
78
● Since the joint axis is not
perpendicular to the
shaft of the humerus,
the forearm alignment
angles laterally in
relation to the shaft of
the humerus in the
anatomical position.
● Cubital angle
Carrying angle
79
Angle of Carryin angle
15°
80
Male (Magee)
5 to 10 degrees
81
Female (Magee)
10 to 15 degrees
82
Cubitus valgu
More than 15 degrees
83
Cubitus varus:
Less than 5 to 10 degrees
84
BOUNDARIES:
● Laterally: Brachioradialis muscle
● Medially: Pronator teres
● Base: Formed by an imaginary line
drawn between the two epicondyles
of the humerus.
● Floor: Formed by the supinator
muscle laterally and the brachialis
muscle medially.
● Roof: Formed by skin and fascia and
is reinforced by the bicipital
aponeurosis.
CONTENTS:
● Median nerve
● Bifurcation of the brachial
artery into the ulnar and
radial arteries
● Tendon of biceps
● Radial nerve
Cubital Fossa
85
● Quite large and comprised
of three distinct parts:
○ Anterior
○ Posterior
○ Transverse.
Medial (Ulnar) collateral ligament
(MCL)
86
● It stabilizes the elbow against excessive valgus forces to
restrict the forearm from excessive lateral displacement
on the arm.
the primary stabilizer of the elbow; damage to
it may result in an unstable elbow joint. .
Medial (Ulnar) collateral ligament
(MCL)
87
● a fan-shaped structure.
● Like the MCL, also has
three parts; these segments
extend from the humeral lateral
epicondyle to the annular
ligament surrounding the radial
head and to the ulna’s olecranon
process.
● This ligament stabilizes the elbow against excessive varus
forces
● Prevents humeroulnar subluxation
● Stabilizes the humeroradial joint
● Assists the annular ligament in stabilizing the radial head
against the ulna.
Lateral (Radial) collateral ligament
(LCL)
88
A large bursa lies between
the olecranon an
Olecranon Bursae
89
● PRUJ
● DRUJ
● Pronation/Supination
● 1 DOF
● Transverse plane, vertical axis
Radioulnar articulation
90
● Located between
radius and ulna.
● This thick membrane
reinforces both
radioulnar joints
without restricting
pronation or
supination motions
Interosseous membrane
91
has firm, fibrous connections to the
ulna, attaching to it on either side of the radial notch,
anchoring firmly around the radial head and neck.
Annular ligament
92
is
quite short but strong,
arising from the ulna just
inferior to the radial notch
and attaching to the
medial surface of the
radial neck.
Quadrate ligament
93
Major stabilizer of the proximal radioulnar joint during full
supination
Anterior portion of the quadrate
ligament
94
● Weaker
● Stabilizes full pronation
Posterior portion of the quadrate
ligament
95
● A flat band of fascia on the
ventral forearm running from the
inferior aspect of the ulna’s radial
notch to just below the ulna’s
radial tuberosity.
● Its fibers run perpendicular to
those of the interosseous
membrane and become taut in
full supination, providing
additional stability to the
Oblique cord
96
● “workhorse”
● Large work capacity due to a large cross section
area.
● Largest of all of the elbow flexors.
● It crosses only the humeroulnar joint.
Brachialis
97
● A fusiform-shaped muscle with two heads located
on the anterior arm.
● Functionally, is selectively recruited
when the task requires elbow flexion with forearm
supination such as in carrying a loaded tray or
bringing a spoon to the mouth.
● Greatest moment arm at 90° to 110° of flexion.
● Large cross section
● Beyond 100° of flexion or when the elbow is close
to full extension, the contractile force becomes
more translatory.
● This translatory force provides
Biceps brachii
98
is a weak elbow flexor,
predominantly contributing to flexion when the
forearm is pronated.
Pronator Teres
99
● Extends the elbow regardless of forearm position
● Its greatest extension force is exerted in midrange at 70° to 90°
of elbow flexion.
● Acts concentrically to extend the elbow.
● Acts eccentrically as a major elbow stabilizer during elbow
flexion.
● Powerful stabilizer of the upper extremity during any functional
closed-chain activity.
Triceps brachii
100
● a small muscle located deep, adjacent
to the joint, blending close to the fibers of the
humeroulnar joint capsule.
● Contracts during elbow extension to tighten the loose
posterior elbow capsule
● Perhaps helping to prevent pinching of the capsule
folds as the olecranon locks into the olecranon fossa
Anconeus
101
● is able to supply adequate force when
○ supination occurs slowly
○ the resistance is light
○ the elbow is extended
● The only muscle whose sole action is forearm supination.
● Always recruited for forearm supination, regardless of the
speed or load.
● Acts alone during slow supination or when the elbow is
extended.
Supinator
102
Aids supination from pronation to midposition with the
elbow in flexion, but its action is quite weak.
Brachioradialis
103
● Primarily a forearm pronator.
● It runs rather close to the axis of the elbow joint so that it
has a poor moment arm for elbow flexion
● This muscle supplies added force to elbow flexion only
when there is a significant resistance or a heavy load.
Pronator Teres
104
● This one-joint muscle performs forearm pronation
regardless of elbow position.
● Acts as a dynamic stabilizer of the distal radioulnar joint
Pronator Quadratus
105
● Injuries to the brachial plexus affect movements and cutaneous
sensations in the upper limb
● Disease, stretching, and wounds in the lateral cervical region
(posterior triangle) of the neck or in the axilla may produce
brachial plexus injuries.
● Signs and symptoms depend on the part of the plexus involved.
Brachial Nerve Palsy
106
cranial portion
Rhomboid minor
107
caudal portion
Rhomboid major
