THE SHOULDER GIRDLE

Movements

Abduction (protraction), Adduction (retraction), Elevation, Depression, Upward rotation, Downward rotation,

Serratus anterior muscle Action

Abduction (protraction): draws the medial border of the scapula away from the vertebrae Upward rotation: Longer, lower fibers tend to draw the inferior angel of the scapula farther away from the vertebrae, thus rotating the scapula upward slightly.

Pectoralis minor action

Abduction, Downward rotation, and Depression

Innervation of the shoulder girdle

Cervical plexus C1-C4 Brachial plexus C5-T1

Rhomboid muscles-Major and Minor Innervation

Dorsal scapular nerve (C5)

Levator Scapulae Innervation

Dorsal scapular nerve C5 and branches of C3 and C4

Levator Scapulae Muscle Action

Elevates the medial margin of the scapula Weak downward rotation weak adduction

Serratus anterior muscle innervation

Long thoracic nerve (C5-C7)

Pectoralis minor innervation

Medial pectoral nerve C8-T1

Subclavius Muscle innervation

Nerve fibers C5 to C6

Trapezius Muscle Origin and Insertion

Origin: Upper fibers: base of skull, occipital protuberance and posterior ligaments of neck. Middle fibers: Spinous process of seventh cervical and upper three thoracic vertebrae Lower fibers: spinous process of fourth through twelfth thoracic vertebrae Insertion: Upper fibers: posterior aspect of the lateral third of the clavicle. Middle fibers: medial border of the acromion process and upper border of the scapular spine. Lower fibers: triangular space at base of the scapular spine.

Pectoralis minor muscle origin and insertion

Origin: Anterior surface of the third to fifth ribs Insertion: Coracoid process of the scapula

Rhomboid Muscles-Major and Minor Origin and Insertion

Origin: Spinous process of the seventh cervical (C7) and first five thoracic vertebrae. (T1-T5) Insertion: Medial Border of the scapula, below the spine of the scapula

Subclavius Muscle origin and insertion

Origin: Superior aspect of first rib at its junction with its costal cartilage Insertion: Inferior groove in the mid portion of the clavicle

Serratus anterior muscle origin and insertion

Origin: Surface of the upper nine ribs at the side of the chest. Insertion: Anterior aspect of the the whole length of the medial border of the scapula

Levator Scapulae Muscle Origin and Insertion

Origin: Transverse process of upper four cervical vertebrae (C1-C4) Insertion: Medial border of scapula from superior angel to scapular spine.

Depression

Returning to normal position from shoulder shrug

Bones involved in movements of the shoulder girdle?

Scapula and the clavicle which move as a unit.

Elevation

Shrugging shoulders

Levator Scapulae Application, Strengthening, and Flexibility

Shrugging the shoulders calls the legator scapulae into play. Extend neck or to flex laterally if used on one side only. The levator scapulae is best stretched by rotating the head approximately 45 degrees contra-laterally and flexing the cervical spine actively while maintaining the scapula relaxed, in a depressed position.

Trapezius Muscle Innervation

Spinal accessory nerve ( cranial nerve XI) and branches of C3, C4

Subclavius Muscle action

Stabilization and protection of the sternoclavicular joint. Depression Abduction

What is the bony link that connects to axial skeleton?

The clavicle's articulation with the sternum.

Rhomboid Muscles-Major and Minor Action

The rhomboid major and minor muscles work together. Adduction (retraction): draw scapula towards the spinal column. Downward rotation Elevation

Rhomboid muscles-Major and Minor Application, Strengthening, and flexibility

The rhomboid muscles fix the scapula in adduction (retraction) when the muscles of the shoulder joint adduct or extend the arm. These muscles are used powerfully in chinning when doing pull ups. It is the rhomboids that rotate the medial border of the scapula down and back toward the spinal column. The trapezius and rhomboids work together to produce adduction with slight elevation of the scapula. Chin ups, dips, and bent over rowing are excellent exercises for developing strength in this muscle. They may be stretched passively moving the scapula into full protraction while maintaining depression.

Serratus anterior muscle Application, strengthening, and flexibility

The serratus muscle is used commonly in movements drawing the scapula forward with slight upward rotation. EX: throwing a ball, tackling in football. It works along with the pectorals major muscle Is used strongly in push ups, bench press, and overhead press. can be stretched by standing facing a corner and placing each hand at shoulder level on the two walls. As you lean in both scapulae are pushed into an adducted position, which stretched the serratus anterior.

Upward rotation

Turning the glenoid fossa upward and moving the inferior angle superiorly

Sternoclavicular Joint (SC)

Type of joint: Anthrodial (gliding) Movements: Protraction,retraction,and rotation Support: Anterior sternoclavicular ligament Posterior sternoclavicular ligament Costoclavicular ligament Interclavicular ligament clavicle moves 15 degrees anteriorly and posteriorly.

Acromioclavicular Joint

Type of joint: Arthrodial (gliding) Movements: Gliding and rotation Support: Coracoclavicular ligaments Superior acromioclavicular ligament Inferior acromioclavicular ligament Has 20 to 30 degree total gliding and rotational motion

Scapulothoracic Joint

Type of joint: Not a true synovial joint Movements: Gliding,rotation,upward rotation, downward rotation, abduction, adduction, elevation, and depression Support: Muscular lacks ligamentous support scapula 25 degree abduction,adduction 60 degree upward, downward rotation 55 degree elevation, depression

Trapezius Muscle Action

Upper Fibers: elevation of scapula, upward rotation, and extension and rotation of the head and neck. Middle Fibers: elevation, upward rotation, and adduction (retraction) of the scapula. Lower fibers: depression, adduction (retraction), and upward rotation of the scapula

Pectoralis minor app, strengthening, and flexibility

Used along with the serratus anterior muscle seen in pushups, dip bars, and body dips. Can be tight causing rounded shoulders. can be stretched by doing a wall push up in the corner. Can also lay supine with towel directly under thoracic spine while partner pushes each scapula into retraction places this muscle on stretch.

Trapezius Application, Strengthening, and Flexibility

When all parts of the trapezius are working together, they tend to pull upward and adduct at the same time. This may be seen in lifting the handles of a wheelbarrow. Strengthening of the upper and middle fibers can be accomplished through shoulder shrugging exercises. The middle and lower fibers can be strengthened through bent over rowing and shoulder joint horizontal abduction exercises from a prone position. The lower fibers can be emphasized with a chest proud shoulder retraction exercise attempting to place the elbows in the back pants pockets with depression. Body dips are also useful for emphasizing the lower traps To stretch the traps: upper fibers may be stretched by using one hand to pull the head and neck forward into flexion or slight lateral flexion to the opposite side. Middle fibers: Same as above but can be stretched further by using a partner to passively pull the scapula into full protraction. Lower fibers: best stretched with subject in a side lying position while a partner grasps the lateral border and inferior angle of the scapula and moves it passively into maximal elevation and protraction.

Adduction retraction of shoulder girdle

pinching shoulder blades together, scapula moving medially

Subclavius muscle app, strengthening, and flexibility

pulls clavicle anteriorly and inferiorly toward the sternum. has significant role in protecting and stabilizing the sternoclavicular joint during upper extremity movements. Can be strengthened during activities which have depression: dips, push ups. Extreme elevation and retraction of the shoulder girdle provide a stretch to the subclavius.

Abduction protraction of shoulder girdle

reaching out for object in front of body , scapula moving away from body.

Downward rotation

returning the inferior angle medially and inferiorly toward the spinal column and the glenoid fossa to its normal position, as in bring bringing arm to the side.