This document provides information about the muscles of the shoulder and common shoulder injuries. It lists the major muscles involved in shoulder movements like flexion, extension, abduction, and rotation. It also discusses common shoulder issues like rotator cuff tears, impingement syndrome, labral tears, and dislocations. Exercises are provided for strengthening the muscles of the shoulder to prevent injuries.
This document provides information about the muscles of the shoulder and common shoulder injuries. It lists the major muscles involved in shoulder movements like flexion, extension, abduction, and rotation. It also discusses common shoulder issues like rotator cuff tears, impingement syndrome, labral tears, and dislocations. Exercises are provided for strengthening the muscles of the shoulder to prevent injuries.
This document provides information about the muscles of the shoulder and common shoulder injuries. It lists the major muscles involved in shoulder movements like flexion, extension, abduction, and rotation. It also discusses common shoulder issues like rotator cuff tears, impingement syndrome, labral tears, and dislocations. Exercises are provided for strengthening the muscles of the shoulder to prevent injuries.
This document provides information about the muscles of the shoulder and common shoulder injuries. It lists the major muscles involved in shoulder movements like flexion, extension, abduction, and rotation. It also discusses common shoulder issues like rotator cuff tears, impingement syndrome, labral tears, and dislocations. Exercises are provided for strengthening the muscles of the shoulder to prevent injuries.
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A Review of the Shoulder
Muscles and Their Actions
Questions What muscle works closely with the anterior deltoid? Pectoralis major What muscle is involved in any lifting movements? Deltoid What is the major (strongest) extensor muscle? Latissimus Dorsi Name the four rotator cuff muscles. Subscapularis, Supraspinatus, Infraspinatus, and Teres minor. What muscle works closely with the infraspinatus? Teres minor Practice Name the muscles for Horizontal Adduction Pect Major (both) Corachobrachialis Deltoid (anterior)
Name the muscles for Horizontal Abduction Deltoid (post) Infraspinatus Teres minor Lats
Practice
List the muscles that do flexion of the shoulder Coracobrachialis Pectoralis major (upper to 60) Anterior Deltoid List the muscles that do extension of the shoulder Latissimus dorsi Teres major Posterior deltoid Pectoralis major (lower fibers to neutral) Practice
List the muscles that do adduction of the shoulder Pectoralis major (lower and upper below 90) Coracobrachialis Latissimus dorsi Teres major List the muscles that do abduction of the shoulder Deltoid (all sections) Supraspinatus Pectoralis major (upper past 90) Practice
List the muscles that do internal rotation of the shoulder Subscapularis Latissimus dorsi Teres major Anterior deltoid Pect. major
List the muscles that do external rotation of the shoulder Infraspinatus Teres minor Posterior deltoid
Name the muscle. Coracobrachialis Name the action Adduction of the shoulder
Also, flexion and hor. add. Name the muscle. Pectoralis Major Name the muscle. Subscapularis Name the action Internal rotation of the shoulder Name the muscle. Deltoid Name the action Abduction of shoulder Name the muscle. Infraspinatus Name the action External rotation Name the muscle. Teres Major Name the action Adduction of scapula Name the muscle. Teres Minor Name the action if the humerus move directly to the posterior Extension of the shoulder Name the muscle. Supraspinatus Name the action Abduction of the shoulder Coracobrachialis Pect. Major Subscapularis Deltoid Supraspinatus Teres Major Infraspinatus Teres Minor What position are her shoulders in? Flexion What position is his right shoulder in? Horizontal Abduction and External Rotation What rotation action is his shoulder performing as he continues to through the ball? Internal Rotation What position are her shoulders in? Flexion What position are his shoulders in? Horizontal abduction or Extension 1. 2. Flexion Extension Position of their shoulders? What is the position of shoulders? Extension Shoulder Muscle Exercises Major Muscles of the Shoulder Pectoralis major Push-ups Pull-ups Bench press Throwing Tennis serve
Shoulder action = ? Shoulder muscle(s) = ? Extension Lats Teres Major Post. Deltoid Pectoralis Major (lower) Infraspinatus Teres minor Shoulder action = ? Shoulder muscle(s) = ? External Rotation Infrspinatus Teres Minor Post. Deltoid Name a shoulder muscle isolated with the following exercises. Side arm dumbbell raises Deltoid Push-ups Pectoralis major Rowing and pull-overs Latissimus dorsi
What is the action to the left? What muscles perform that action? Internal Rotation External Rotation Internal Rotation Subscapularis, Ant. Deltoid, Pect, Major, Lats. And Teres Major Rotator Cuff Exercises External Rotation External Rotation Internal Rotation Abduction (to work the supraspinatus) Shoulder Related Injuries
The shoulder is built for motion, not stability Injury rate depends on Shallowness of glenoid fossa Laxity of ligaments Strength of muscles Shoulder subluxation Incomplete or partial dislocation Shoulder dislocation Complete dislocation of the GH joint Most common anteriorly and inferiorly
Shoulder separation Complete dislocation of the AC joint Shoulder Dislocation Impingement Syndrome
Impingement Syndrome A condition that decreases the subacromial space Acromion process Coracoacromial ligament Causes Swelling Bone spurs Anatomical structure Impingement Syndrome Rotator Cuff Tears Rotator cuff Subscapularis Supraspinatus Infraspinatus Teres minor Movement of RC Muscles Subscapularis is an internal rotator of the arm. Supraspinatus assists the deltoid in abducting the arm, with its greatest contribution being the initiation of abduction. Infraspinatus and teres minor muscles both externally rotate the arm. Rotator Cuff Injury The throwing motion has been divided into five phases: wind-up, cocking, acceleration, and follow-through. Cocking phase Subscapularis fires in late cocking phase to decelerate the shoulder's external rotation. Also, it is stretched during the cocking phase. Rotator Cuff Injury Follow-through (muscles fire most intensely) Subscapularis internally rotates the shoulder, The infraspinatus and teres minor contract eccentrically to decelerate the arm and are stretched. During this repetitive eccentric loading, the rotator cuff is prone to overload, fatigue, tendinitis, and even a partial undersurface tear. Note: Surgery needs to be performed within 3 months or the supraspinatus muscle will atrophy and be too short to reattach Glenoid Labrum Labral Tear The glenoid cavity makes up the socket of the shoulder joint. The labrum acts sort of like a gasket, turning the flat surface of the glenoid into a deeper socket that molds to the head of the humerus for a better fit. A tear of labrum can cause pain and a catching sensation with movement of the shoulder. Labral Tear Most labral tears are probably the result of an injury to the shoulder, such as falling on an outstretched hand. There is reason to believe that the excess motion of the humerus moving around on the glenoid may cause damage to the labrum over time. An unstable shoulder may also cause injury to the labrum, if it repeatedly dislocates out of the glenoid.