SK lecture 8, shoulder joint

winniesmith2's version from 2018-05-14 16:41

Section 1

Question Answer
Describe the glenohumeral (shoulder) joint • Ball & socket joint • Most mobile joint in the body • Price of mobility is reduced stability
Name 2 features of the glenohumeral joint Labrum- cartilage around socket to make it deeper and the fibrous joint capsule.
Complete the following actions of the glenohumeral joint and check on pg 2 External and internal rotation. Flexion, extension and hyperextension. Adduction and Abduction. Horizontal abduction and adduction,
What are the superficial anterior muscles Pectoralis major
What are the superficial posterior muscles latissimus dorsi and teres major
What are the superficial superior muscles deltoid
What are the superficial biarticular brachial muscles biceps brachii and triceps brachii
What are the deep rotator cuff musclesSupraspinatus, Infraspinatus, Teres minor, Subscapularis (SITS)

Section 2

Question Answer
Actions of the pectoralis majorAdduction, Horizontal adduction and internal rotation
Pectoralis majorO- medial half of clavicle, sternum and cartilage of 1st through 6th ribs. I- crest of greater tubercle of humerus.
Actions of the latissimus dorsi Adduction, Horizontal abduction, extension and internal rotation.
Latissimus Dorsi O- ribs T7- sacrum, iliac crest. (plus spinous process of inferior angle of scapula and last 3/4 ribs). I- Intertubercular groove of the humerus.
Actions of the Teres Major Adduction (bit of horizontal abduction) extension and internal rotation.
Teres MajorO- Inferior angle and lower one-third of lateral border of the scapula. I- Crest of the lesser tubercle of the humerus.

Section 3

Question Answer
What are the actions of the anterior deltoidAbduction, flexion, horizontal adduction
What are the actions of the middle deltoidabdution
What are the actions of the posterior deltoidAbduction, extension, horizontal abduction, external rotation.
Anterior DeltoidO- lateral 3rd of clavicle (anterior) I- deltoid tuberosity
Middle DeltoidO- Acromion process I- Deltoid tuberosity
Posterior DeltoidO- Lower lip of scapula spine. I- deltoid tuberosity.

Section 4

Question Answer
Action of the Subscapularis Internal rotation
Subscapularis O- Subscapular fossa of the scapula. I- Lesser tubercle of the humerus.
Action of the supraspinatusExternal rotation (Abduct the shoulder)
SupraspinatusO- Supraspinous fossa of the scapula. I- Greater tubercle of the humerus.
Action of the infraspinatusExternal rotation (adduct the shoulder)
InfraspinatusO- Infraspinous fossa of the scapula. I- Greater tubercle of the humerus
Action of teres minorExternal rotation (adduct the shoulder)
Teres MinorO- upper 2/3rds of lateral border of the scapula. I-Greater tubercle of the humerus.
What do all the rotator cuff muscles do Provide important stability for the humeral head.

Section 5

Question Answer
Rotator cuff injuries are susceptible to Susceptible to damage from rapid/ ballistic overhead activities - throwing & racket sports.
What are the 2 types of rotator cuff injuries1. Muscle/tendon strain. 2. Impingement
What is muscle/tendon strainOccasionally rupture due to high & excessive forces.
What is impingement Typically due to compression of the supraspinatus in the subacromial space . - small subacromial space - supraspinatus hypertrophy - shoulder joint laxity
What is the action of the long head of the triceps brachii (in shoulder movements)Extension, adduction and Horizontal abduction.
Triceps brachii long headI- infraglenoid tubercle of the scapula. I- Olecranon process of the ulna.
What is the action of the biceps brachii (in shoulder movements)Weak shoulder flexion
Biceps brachii coracoid process of scapula (short head) supraglenoid tubercle of scapula (long head) I- Tuberosity of the radius and aponeurosis of the biceps brachii.
Describe shoulder dislocations 98 % are Anterior dislocations 2 common causes: ♦ Excessive abduction and external rotation ♦ Impact that forces the humeral head forwards