A.A.A. Contest Answerthe Animated AnimaLS • Throughout the slide show there will be slides with written questions. • When you see a question, think of the answer, don’t answer it out loud --- this way, everyone gets a chance to think. • Some slides with a question will have animations of animals cross the screen. When this happens, write down the answer on a post it note and quickly WALK it up to post on the board at the front of the class. • The first person to post the correct answer on the board is the winner! You get to put a sticker on the “AAA Contest” board. • The contest will continue throughout the quarter… at the end of the quarter, the person with the most stickers wins! The winner gets a sur-Prize
Bones of Shoulder • Humerus • & • The shoulder girdle: • Scapula • Clavicle
The shoulder girdle • attachment of the upper extremity to the trunk • It consists of two bones: • the scapula (shoulder blade) • clavicle (collarbone)
Shoulder GirdleScapula & Clavicle • Link to Axial skeleton via sternoclavicular joint • Lack of posterior attachment to the axial skeleton allows for a wide ROM • Functions to allow attachment areas for numerous muscles that move the shoulder and elbow
What is the only true synovial joint where there is an articulation between the humerus and the axial skeleton? Sternoclavicular joint
Landmarks of Scapula • Borders • superior, medial (vertebral), lateral (axillary) • Angles • inferior, superior • Acromion process • Spine of scapula • Glenoid fossa • Coracoid process • Supraspinatus fossa, Infraspinatus fossa, Subscapular fossa • Supraglenoid tubercle & Infraglenoid Tubercle
Anterior View of Shoulder Complex: With Scapula, Humerus and Clavicle
Lateral View of Scapula (Sagittal Cross Section) Anterior Posterior
Learning Activity: • Label the landmarks of the scapula • 1st try from memory • (in a couple of minutes Zefire will put up a labeled picture so you can double check your answers, make corrections and additions)
Joints of theShoulder Girdle • Sternoclavicular joint 2. Acromioclavicular Joint • Glenohumeral Joint (4) Scapulothoracic Joint - NOT really a synovial joint • supported by muscles, not ligaments
Joints of theShoulder Girdle 1. Sternoclavicular • Sternum and clavicle • gliding joint • ligaments • anterior sternoclavicular ligament • posterior sternoclavicular ligament • costoclavicular ligament • interclavicular ligament
Joints of theShoulder Girdle 2. Acromioclavicular • Acromion Process of scapula and clavicle • gliding joint • ligaments • coracoclavicular ligaments • trapezoid ligament • conoid ligament • superior & inferior acromioclavicular ligaments
Acromioclavicular Joint The joint is surrounded by a weak capsule that is reinforced by strong inferior and superior * acromioclavicular ligaments. Further strengthening occurs through the coracoclavicular ligament formed of two strong fibre bundles, the lateral trapezoid and medial conoid ligaments.
Joints of theShoulder Girdle: 3. Glenohumeral • Glenoid fossa and head of the humerus • Ball and socket • Joint that allows most movement of entire body • Allows movement in 3 planes
“Shoulder Joint”: Glenohumeral Joint Process Fossa Fossa Labrum: a ring of fibrous cartilage surrounding the glenoid stabilizes the joint (makes a deeper socket)
“Shoulder Joint”: Glenohumeral Joint
Glenohumeral Joint: What is the bony landmark on the scapula that articulates with the humerus? Glenoid Fossa
Movements allowed by the “Shoulder” Glenohumeral Joint: Flexion + Extension ADduction + Abduction Circumduction: Flexion + Extension + Adduction + Abduction Medial Rotation + Lateral Rotation Horizontal ABduction + Horizontal ADduction
Movements allowed bythe Scapulothoracic “joint” • Abduction (Protraction) • Adduction (Retraction) • Depression: inferior movement • Elevation: superior movement • Downward (inward) rotation: inferior angle moves medially • Upward (outward) rotation
Movements allowed bythe Scapulothoracic “joint” • Abduction (Protraction) – scapula move away from spine • Adduction (Retraction) – scapula move closer to spine
Protraction Retraction Bring shoulder blades closer together. A widening across front of collarbone will occur. Try to keep space between the hands constant. Reach fingers forward. A widening between shoulder blades will occur. Try to keep space between the hands constant.
Movements allowed bythe Scapulothoracic “joint” • Depression: inferior movement • Elevation: superior movement
Movements allowed bythe Scapulothoracic “joint” • Downward (inward) rotation: inferior angle moves medially, and acromion moves downward • Upward (outward) rotation: inferior angle moves laterally, and acromion moves upward
Scapular Movements in Action What is the movement at the scapula as this man contracts his muscles? Elevation Superior movement of the shoulder girdle; moving the scapula up. http://www.exrx.net/Articulations/Scapula.html#anchor73267
Scapular Movements in Action Besides some depression of the scapula, what other primary motion is occurring at the scapula during the pull up? • Downward Rotation • Rotary movement of the scapula; Moving inferior angle of scapula medially and downward.
Scapular Movements in Action Upward Rotation Rotary movement of the scapula; Moving inferior angle of scapula laterally and upward.
Scapular Movements in Action During the push-up phase of the movement, what is the scapular action? Abduction (Protraction) Forward movement away the midline of the body; moving the scapula away from the spine.
Scapular Movements in Action What scapular movement is occurring during contraction? Adduction (Retraction) Backward movement toward the midline of the body; moving the scapula back toward the spine.
The scapula moves normally on the thorax only if the two joints by which it attaches to the axial skeleton are also free to move: Sternoclavicular joint Acromioclavicular joint
Sternoclavicular (SC) joint movements: CLAVICULAR ELEVATION AND DEPRESSION Clavicular protraction and Retraction BACKWARD AND FORWARD ROTATION OF CLAVICLE OCCUR
Acromioclavicular joint Mobility at the AC joint allows the scapula to move in three dimensions so that it follows the contours of the ribcage. Scapular WINGING TIPPING UPWARD and DOWNWARD ROTATION
During shoulder elevation, the scapula and clavicle must rotate upwardly
Humeral Flexion and Extension http://www.biomech.jhu.edu/Projects/shoulder/Default.htm
Learning Activity: • Individually, without your notes • Take 10 minutes to write an outline of the movements possible at the • Glenohumeral joint • Scapulothoracic “joint” Then, answer these questions: Which of these joints allows more movement: AC - acromioclavicular joint or sternoclavicular joint? In how many planes does this more moveable joint allow movement? Try drawing diagrams to see if that helps
Learning Activity: 2) In small groups, your answers; make sure everyone understands. 3) With a scapula model, take turns, with each person showing the scapulothoracic movements on a group member’s back (while other group member(s) watch and help).