PHTY101 Lecture Notes - Lecture 2: Latissimus Dorsi Muscle, Shoulder Girdle, Rhomboid Minor Muscle
Document Summary
2. 1 identify, state the attachments and deduce the actions of the muscles of the axillary and scapular regions: muscles connecting the axial skeleton and the humerus, pectoralis major - sternal head: Action: flexes and adducts arm, and rotates arm medially. Origin: spinous processes t7 l5, iliac crest and the last 3 ribs. Action: extends, adducts and medially rotates the humerus at. Insertion: intertubercular sulcus of the humerus the shoulder. Note: this sits between the pectoral major and the and teres major. Origin: superior nuchal line, spinous processes c7 t12. Action: elevates, retracts and rotates scapula (lower fibres. Insertion: lateral third of clavicle, acromion and spine of scapula depress scapula) This is the long thick muscle that passes down the back, however all the fibres do different things: rhomboid major. Insertion: medial border of scapula, below the base of the spine of scapula. Action: fixes scapula to thoracic wall, and retracts an rotates it to depress glenoid cavity.
