m4: shoulder and elbow Flashcards
(125 cards)
● 20 muscles
● 3 bony articulations
● 3 soft tissue moving surface (functional joints)
● Permit the greatest mobility of any joint area found in the body
● 16,000 different positions (hand placement)
● stabilizes the upper extremity for hand motions
● lifts and pushes objects
● elevates the body
● assists with forced respiratory inspirations and expirations
● bears weight when walking with crutches or performing handstands
● Mobility > Stability
shoulder
only bony attachment of UE to trunk.
sternoclavicular joint
primary support and stabilizer of the shoulder
muscles and ligaments
● ___ joint = glenohumeral joint
● Shoulder ___ = all structures which make up the shoulder.
shoulder ; complex
4 bones of shoulder
manubrium
clavicle
scapula
humerus
● Shoulder girdle
○ Manubrium
○ Right and left ____
○ Right and left ____
● ___ girdle (does not have bony connection posteriorly)
clavicles
scapulaes
incomplete
● Clavicular facet
● Sternal/jugular notch
● Facets for attachment of the first ribs
manubrium
● Lateral strut to the scapula and the humerus.
● This increases glenohumeral mobility to permit greater motion in reaching and climbing activities.
● Medial end
● Costal facet
● Costal tuberosity
● Acromial end
clavicle
● 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
● Inferior angle (T7)
● Vertebral border (medial border)
● Axillary border (lateral border)
● Glenoid fossa (the most lateral aspect of the scapula) ● Supraglenoid tubercle (attachment for LH of biceps) ● Infraglenoid tubercle (attachment for LH of triceps) ● Superior border
● Scapular spine (T3)
● Supraspinatus fossa
● Infraspinatus fossa
● Acromion process
● _____ (crow’s beak)
scapula
coracoid process
● Dense fibrous connective tissue rim that surrounds the glenoid fossa.
● Increase joint congruence.
● Tilted _ ° upward relative to the scapular vertebral border.
● Teardrop or pear-shaped appearance
● Orientation: _ , _ , _
● (Concave)
glenoid labrum
5°
LAS
● Head of humerus
○ Convex
○ 1/3 to 1⁄2 sphere
○ Orientation: _
● Humeral neck (anatomic neck)
● Humeral shaft
● Angle of inclination = humeral head is angled at _° to the long axis of the humeral shaft
● Angle of torsion = _°
● 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 = _
● Greater tubercle
● Lesser tubercle
● _ (intertubercular groove)
○ through which the LH of biceps runs from its proximal insertion on the supraglenoid tubercle.
humerus
medial, superior, posterior (PMS)
135
30
Retroversion
Bicipital groove
● Circumferential area on the proximal humerus.
● Distal to the _ _
● Common site for humeral fractures, especially in the elderly, when a fall occurs and the individual lands on an outstretched arm.
surgical neck
bicipital groove
synovial joints of shoulder
● Sternoclavicular joint
● Acromioclavicular joint
● Glenohumeral joint
● Scapulothoracic joint
a joint responsible for the majority of the scapular movement.
sternoclavicular joint
provides minimal movement and acts more as a fine tuner of scapular motion than a producer of its motion.
acromioclavicular joint
the result of sternoclavicular and acromioclavicular joint movements.
scapulothoracic motions
Shoulder Girdle Movements
● Elevation
● Depression
● Protraction
● Retraction
● Upward Rotation
● Downward Rotation ● Scapular Tilting
○ A-P
○ M-L
● 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.
sternoclavicular joints
_____ has
○
○ 3 strong stabilizing ligaments
1
2
3
sternoclavicular joint ligaments
Fibrocartilaginous articular disc
anterior SC ligament
posterior SC ligament
superior SC ligament
2 Coracoclavicular Ligaments
● Conoid
● Trapezoid
____ Joint
● 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
● Superior AC ligament
● Inferior AC ligament
Acromioclavicular
● no bony articulations
● False joint/pseudo joint/functional joint
● Separating the scapula from the thorax are soft tissue structures, including a large subscapular bursa.
scapulothoracic joint
● Increasing the range of motion of the shoulder to provide greater reach
● Maintaining favorable length-tension relationships for the deltoid muscle to function above _ ° of glenohumeral elevation to allow better shoulder joint stability throughout a greater motion
● Providing glenohumeral stability through maintained glenoid and humeral head alignment for work in the overhead position
● Providing for injury prevention through shock absorption of forces applied to the outstretched
scapulothoracic function
90
● Shoulder joint
● Ball-and-socket
● 3 DOF
● Little bony stability
○ Convex:
○ Concave:
● Labrum
○ From neck of glenoid
○ To anatomic neck of humerus
● 10 to 15 mL
● Axillary pouch
Glenohumeral Joint
Humeral head (PMS)
Glenoid fossa (small/shallow) (LAS)