-
What are the functions of the shoulder?
- Mobility – the shoulder motion (combined withthe elbow) allows for infinite possibilities of hand positioning in space
- Stability – the shoulder must be stabilized tomaximize hand function
-
What bones make up the shoulder?
- Sternum & ribs
- Clavicle
- Scapula
- Humerus
-
What joints make up the shoulder?
- steroclavicular
- acromioclavicular
- glenohumeral
- scapulothoracic (not a true joint)
-
What is the only axial skeleton attachment of the upper limb?
Sternum
-
What are the parts of the sternum?
- Manubruim - clavicular facets and costals facets
- body - rib attachment
- xiphoid process
- sternal (jugular) notch
- sternal angle - used to count the ribs starting with the second
-
How is the clavicle of strut?
The clavicle links the axial skeleton to appendicular skeleton
-
What are the parts of the clavicle?
The clavicle is s-shaped. It anterior surface is convex medially and concave laterally. When the bone breaks, it fractures at the part between both ends
-
What is the normal clavicular position?
- angled 20 degrees posterior to frontal plane
- angled 10 degrees superior to horizontal plane (medial to lateral)
-
What are the parts of the scapula?
- Bony shape - thin, triangular bone
- 3 angles - inferior, superior medial, and lateral
- 3 borders - medial, superior, and lateral
- invested in muscle
- structures - scapular spine, acromion, glenoid fossa, and coracoid
-
The scapular spine divides the posterior surface into what two areas? What muscles attach there?
- The spine divides posterior scapular surface into supraspinous fossa and Infraspinous fossa
- Muscles attached here are Deltoid and Trapezius
-
Where is the acromion located?
the acromion is the lateral end of the scapular spine and articulates with the clavicle at the clavicular facet
-
What muscles attach to the acromion?
the deltoid and the lower/middle fibers of trapezius
-
What ligament forms an arch over the glenohumeral joint?
coracoacromial ligament
-
What is the glenoid fossa?
pear shaped concavity for the humerus and it articulates with the humeral head
-
What is the shape of the glenoid fossa?
only 25% surface area of the humeral head
-
What is the glenoid labruim?
- composition - dense fibrous tissue
- function - deepens glenoid from 2.5mm to 5mm
- long head of biceps brachia attaches on the superior aspect
-
-
What is the normal glenoid fossa orientation?
- glenoid tilt - 4 degrees upward tilt (range - 7 degrees downward tilt; 16 degrees upward tilt)
- plane of the scapula - angled at 35 degrees from frontal plane (lateral edge is more anterior than medial edge)
-
What is shaped like a “crow’s beak”?
coracoid process
-
What ligaments attach to the coracoid process?
- Coracoacromial
- Coracohumeral
- Coracoclavicular
-
What muscles attach to the coracoid process?
- Pectoralis minor
- Short head biceps
- Corcobrachalis
-
What are landmarks of the proximal humerus? And what muscles attach there?
- Necks - anatomic and surgical
- tuberosities - greater [subscapularis] & lesser [teres minor, infraspinatus, supraspinatus]
- bicipital groove - pectorals major, teres major, and latissimius dorsi
- deltoid tuberosity - deltoid
- radial groove
-
What is the angle of inclination for the humerus?
130° - 150° (normal)
-
What is the angle of torsion for the humerus?
30° - 50° retroverted (does itlook anterior or posterior – so the humeral looks back about 30-50 degreescompared to the epicodyles)
-
What controls the scapulothoracic motions?
AC joint & SC joint
-
What are the motions of the scapula?
- Elevation – depression of scapula
- Protraction-retraction of scapula
- Upward-downward rotation of scapula - coupling must occur in order to complete this action [AC joint] [inferior angle]
- Anterior-posterior tilting of scapula (based on the top of the scapula) – again coupling must occur in order to complete this action [AC joint]
- Internal-external rotation of scapula [medial and lateral rotation] [based on glenoid cavity) – coupling must occur in order to complete this action
-
What is the sternoclavicular joint?
Axial attachment – most proximal joint links shoulder complex to axial skeleton
-
What kind of joint is the sternoclavicular joint?
saddle
-
What are some characteristics of the articular disc of the sternoclavicular joint?
- Fibrocartilage
- Joint congruity improves fit
- Shock absorption
-
What are the ligaments of the steroclavicular joint? What are some characteristics of each?
- Sternoclavicular ligaments intrinsic ligament; reinforces the capsule {anterior and posterior}
- Costoclavicular ligaments - 1. First rib to clavicle 2. Major SC stabilizer 3. Limits all motions but depression
- Interclavicular ligament limits depression
-
How many degrees of freedom does the SC joint have? What are they?
- Three - elevation/depression, protraction/retraction & axial rotation of clavicle
-
-
For clavicle elevation and depression, what isthe plane and axis? What are the normal available ranges for this movement?
- Plane & axis frontal plan; anterior/posterior axis
- Available ranges 45 degree elevation, 10 degree depression [what position is start position in normal posture? – 10 degrees]
-
What are the arthrokinematics of elevation and depression of the clavicle?
- Elevation - clavicle rolls superior; clavicle glides inferior
- depression - clavicle rolls inferior; clavicle glides superior
-
For clavicle protraction and retraction, what is the plane and axis? What are the normal available ranges for this movement?
- Plane & axis horizontal plane; axis
- Available ranges 15-30 degrees each direction
-
What are the arthrokinematics of protraction and retraction of the clavicle?
- retraction - clavicle rolls superior; glides superior
- protraction - clavicle rolls inferior; glides inferior
-
For clavicle axial rotation what is the plane and axis? What are the normalavailable ranges for this movement?
- Plane sagittal plane; medial/ laterial axis
- Ranges superior aspect of clavicle rotates posterior 40-50 degrees with should elevation
-
What are the arthrokinematics of axial rotation of the clavicle?
spin of clavicle on sternum [no roll and glide – SPIN]
-
What kind of joint is the AC joint?
plane joint
-
What are the articulating surfaces of the AC joint?
- Lateral end of clavicle
- Clavicular facet on acromion
-
What are the ligaments of the AC joint?
- Acromioclavicular {intrinsic}- Superior and Inferior
- Coracoclavicular [ice hockey] - Trapezoid & Conoid
-
How many degrees of freedom does the AC joint have? What are they?
- Upward/downward rotation of scapula
- Anterior/posterior tipping of scapula
- Medial/lateral rotation of scapula
-
What is the scapulothoracic joint?
- No bone-bone contact - NOT A TRUE JOINT
- Anterior surface of scapula
- Posterior thoracic wall
-
What is the scapula’s normal position?
- Between ribs 2 &7
- Medial border 6cm from thoracic spinous processes
- Scapular plane: 35 degrees anterior to frontal plane
-
What are the articular surfaces of the clavicle? What ligaments are attached to the clavicle?
- Articular surfaces - Sternal end & Acromial end
- Costal tuberosity - attachment of costocalvicular ligament
- Conoid tubercle - attachment of coraclavicular ligament
-
Does the AC joint have a disc?
it varies!
|
|
