Shoulder Complex Flashcards
Scapulothoracic upward rotation
Serratus anterior
Upper trap
Lower trap
Scapulothoracic downward rotation
Rhomboids
Pec minor
Levator scapulae
Scapulothoracic elevation
Upper trap
Levator scapulae
Rhomboids
Scapulothoracic depression
Subclavius
Latissimus dorsi
Lower trap
Pec minor
Serratus anterior
Scapulothoracic protraction
Serratus anterior
Pec minor
Pec major
Scapulothoracic retraction
Middle and lower trap
Rhomboids
Scapular winging possible causes (3)
Muscle weakness - serratus anterior, trapezius, rhomboids
AC joint dysfunction (hyper\hypo mobility)
Kyphosis
Slouched posture (shortened pec minor)
Muscles responsible for Scapulothoracic joint elevation
Upper trapezius
Levator scapulae
Rhomboids (major and minor)
Muscles responsible for Scapulothoracic joint depression
Lower trapezius
Latissimus dorsi
Pectoralis minor
Subclavius
Muscles responsible for Scapulothoracic joint retraction
Rhomboids
Middle and lower traps
Muscles responsible for Scapulothoracic joint upward rotation
Upper and lower trap
Serratus anterior
Muscles responsible for Scapulothoracic joint protraction
Serratus anterior
Pec minor
Muscles responsible for Scapulothoracic joint downward rotation
Rhomboids
Pec minor
Levator scapulae
Head of humerus normal position?
30* retroverted
Normal clavicle position (degrees?)
20* posteriorly rotated
Normal scapular position? (Degrees)
35* anteriorly rotated
Superior transverse scapular ligament (nerve and artery?)
Suprascapular nerve passes under ligament (Suprascapular notch)
Suprascapular artery passes over ligament
Shoulder joint stability **incomplete
4* anteriorly rotated glenoid fossa?
Scapulothoracic stability
Resting position of scapula (3 planes + degrees of rotation?)
35-45* anteriorly? Or laterally? rotated (transverse plane)
10-20* inferiorly rotated? (Sagittal plane)
5-10* upward rotation (frontal plane)
Complications regarding the surgical neck of the humerus?
More likely to fracture and the axillary nerve passes through there - could also be a site of/for impingement?
Humerus angle of inclination? Torsion?
135*
30* retroverted - more retroversion = more external rotation (e.g. baseball pitcher)
Sternoclavicular joint type? Convex/concave surfaces?
Diarthrodial, double saddle
Longitudinal - clavicle is convex manubrium/sternal articulation is concave
Transverse is opposite - clavicle concave, sternal articulation is convex
Sternoclavicular planes of motion?
3
Elevation/depression (superior, inferior translation)
Protraction/retraction (anterior, posterior translation)
Anterior/posterior rotation
Depression of Sternoclavicular joint causes?
Brachial plexus (anterior and posterior divisions) and artery (superiorthoracic and axillary) compression
Sternoclavicular ligaments - articular disk considered a part of what with elevation/depression?
Sternum, Clavicle is moving over the articular disk and manubrium
Sternoclavicular ligaments - articular disk considered a part of what with protraction/retraction?
Clavicle and articular disk moving over the manubrium
Significance of interclavicular ligament?
Attaches two clavicles, limits depression
Costoclavicular ligament limits?
Elevation
Sternoclavicular ligament limits?
Anterior/posterior translation - posterior bundle is thicker
Anterior/posterior rotation of the clavicle - which is there more of?
Posterior rotation - plays significant role in closed pack position
Anterior rotation is essentially coming back to the resting position
Sternoclavicular joint kinematics - elevation/depression, limits
Convex clavicle surface moving on concave sternal surface
Elevation = superior roll and inferior glide w superior translation (and vice versa) *limited by costoclavicular ligament
Depression limited by interclavicular ligament and superior capsule of SC jt
Sternoclavicular joint kinematics - protraction/retraction, limits
Concave clavicle surface moving on convex sternal surface - roll/glide in SAME direction
Protraction = anterior roll and anterior glide, limited by posterior capsule of SC jt
Retraction = posterior roll and glide, limited by anterior capsule and costoclavicular ligament
Sternoclavicular joint kinematics - anterior/posterior roll
Posterior roll (inferior side of clavicle starts facing anteriorly) needed for full arm raise (180*)
Scapulothoracic rhythm
2:1 ratio of movement - glenohumeral (120) to Scapulothoracic(60)
Arcade of frohse can cause?
Impingement of posterior interosseous branch of radial nerve (PIN) causing wrist drop
Finger trick (humerus, triceps long head, teres minor, teres major)
Quadrangular space - axillary nerve, posterior humeral circumflex artery
Triangular space - scapular circumflex
Triangular interval - radial nerve, deep brachial artery
Cubical fossa (borders: humeral epicondyles, Brachioradialis, Pronator teres)
Contents: Really Need Booze To Be At My Nicest
Radial nerve
Biceps tendon
Brachial artery
Median nerve
Streuther’s ligament may compress?
Median nerve
Median nerve compression/ injury may lead to condition called?
Pronator’s Syndrome
The term “shoulder movement” describes
The combined motions at both the glenohumeral and Scapulothoracic joints
As a result of the shoulder complex being connected to the axial skeleton by a single joint (sternoclavicular), muscles/muscle forces serve as a primary mechanism for?
Securing the shoulder girdle to the thorax (Scapulothoracic articulation) and providing a stable base for upper extremity movements
The scapular plane is defined by 3 angulations of the scapula at rest. What are they?
Internally rotated 35-45*
Anteriorly tilted 10-15*
Upwardly rotated 5-10*
Surgical neck of the humerus is below the anatomical neck below the tubercles. A fracture here is more or less likely than at the anatomical neck?
More likely and would cause damage to the axillary nerve and posterior circumflex humeral artery (contents of the quadrangular space)
SC joint movement during shoulder movements: 1st 30* upward rotation of the scapula requires what motion at the SC joint?
Upward rotation of scapula from 30-60* requires what motion at SC joint?
Elevation
posterior rotation
Coracoclavicular ligament comprised of what ligaments?
Trapezoid - resists posterior directed forces applied to the lateral/distal clavicle
Conoid - resists superior directed forces applied at the distal clavicle or inferiorly directed forces applied to the acromion
As a whole the coracoclaviclar ligament limits upward rotation of the scapula at the AC jt
AND couples posterior rotation of the clavicle with upward rotation of the scapula
Upward rotation of the scapula and AC jt coincides with posterior rotation of the clavicle and WHAT at the coracoclavicular ligaments?
Slack - posterior rotation of clavicle releases tension on the coracoclavicular ligaments
Scapulothoracic upward rotation is the result of the combined motions at the SC and AC joints. What are they?
SC elevation and posterior rotation of the clavicle
AC upward rotation
Upward/downward rotation of Scapulothoracic joint - axis of first 30*
Last 30*?
Base of spine of scap
AC jt
Upward rotation muscles (3)
Serratus anterior
Upper and lower trap
Downward rotation (3)
Rhomboids
Pec minor
Levator scapulae
Elevation of Scapulothoracic joint is comprised of motion at the clavicle and AC joints
Clavicular elevation at the SC jt
Scapular downward rotation and anterior tilt at AC joint
Muscles responsible for elevation of Scapulothoracic jt (3)
Levator scapulae
Upper trap
Rhomboids
Muscles responsible for depression at Scapulothoracic joint
Serratus anterior
Lower trap
Subclavius
Pec minor
Latissimus dorsi
Scapulothoracic joint protraction comprised of motion at SC and AC
SC protraction
AC internal rotation
Glenoid labrum increases depth of glenoid fossa by?
50%
Glenohumeral joint capsule tightens with what two motions at the humerus
Abduction and lateral/external rotation
Rotator cuff muscle tendons provide additional stability to what important structure at the shoulder?
Glenohumeral joint capsule - bc they insert directly onto and blend into the capsule
Glenohumeral joint ligaments (3)
Glenohumeral ligaments (superior, middle, inferior)
Coracohumeral
Coracoacromial
Glenohumeral capsule is taught in some places and loose in others. What directions?
Taut superiorly
Slack anteriorly and inferiorly
Hill-Sachs lesion/fracture associated with? located where?
Cortical depression in the Posterolateral head of humerus caused by forceful impact against anteroinferior glenoid rim in the case of a shoulder dislocation
Anterior shoulder dislocation associated with what injuries? (4)
Bankhart lesion (damage to labrum)
Hill-Sachs lesion
Axillary and/or Suprascapular nerve damage
