Transcript Group 2 Presentation

Clavicle, Scapula, & Thorax
Jenna Erickson, Becca Goldstein,
Sam McKeon, Alissa Migliore, &
Stephanie Vicari
Types of Joints in Clavicle
• Glenohumeral joint- also known as the shoulder joint, is a
synovial ball and socket joint and involves articulation
between the glenoid fossa of the scapula (shoulder blade)
and the head of the humerus (upper arm bone). It helps you
move your shoulder forward and backward. It also enables
your arm to rotate in a circular manner or move outward.
The glenohumeral joint is composed of the socket on your
shoulder blade (glenoid) and the "ball" at the top of your
arm bone (the humerus). Uniquely, the ball of the upper
arm bone is twice the size of the shoulder blade socket.
• A false joint is formed where the shoulder blade glides
against the thorax (the rib cage). This joint, called the
scapulothoracic joint, is important because it requires that
the muscles surrounding the shoulder blade work together
to keep the socket lined up during shoulder movements.
Types of Joints in Clavicle
(contd)
• Sternoclavicular joint (SCJ)- is the connection of the
sternum (breastbone) to the clavicle (collarbone). A freely
moveable synovial joint links the upper extremity to the
torso, with the sternoclavicular joint (SCJ) participating in
all movements of the upper extremity. The SCJ is a saddletype joint that provides free movement of the clavicle in
nearly all planes. The ability to thrust the arm and shoulder
forward requires sound function of the SCJ.
• Acromioclavicular joint (ACJ)- is the gliding joint that is
located between your shoulder blade (acromion) and your
collar bone (clavicle). It is part of the mechanism that
allows the shoulder to rise and fall (shrug), and to raise the
arm above the head. It functions as a pivoting joint,
although technically it is a gliding synovial joint
Articulation
• 1.Acromioclavicular Joint
 1.Planar type joint between lateral portion of the clavicle and
the acromion of the scapula.
• 2.Sternoclavicular Joint
 1.Sellar joint between the medial end of the clavicle and the
manubrium of the sternum.
• 3. Glenohumeral ( Shoulder ) Joint
 1.Ball and socket articulation between head of humerus and
glenoid cavity.
 2.Favors mobility over stability
• 4.Scapulothoracic "Joint”
 1.Scapula suspended on rib cage by muscles
• 1.highly mobile
 2.capula movements increases range of motion at the
shoulder joint
Scapula
• The scapula is suspended on the thoracic wall by muscle
forming a "functional joint" called the scapulothoracic joint.
These muscles act to stabilize and/ or to actively move the
scapula. Active movements of the scapula help increase the
range of motion of the shoulder joint.
• Scapulothoracic Articulation
 1. Stability
• 1.Dependent upon activity of extrinsic muscles
• 2.Winged scapula
 2. Alignment
• 1.Upwardly rotated and elevated position of scapula at
rest
 1.action of trapezius muscle
Movements of the Scapula
• 1.Elevation - moving the superior border of the scapula and the
acromion in an upward direction.
• 2.Depression - moving the superior border of the scapula and
the acromion in an downward direction.
• 3.Upward Rotation - Moving the scapula so that the glenoid
cavity faces upward.
 1.Increased the ranges of motion during abduction and/or flexion of
the shoulder.
• 4.Downward Rotation - moving the scapula so that the glenoid
cavity faces inferiorly.
 1.Increases range of motion during extension and / or adduction of
the shoulder.
• 5.Protraction ( Abduction) - moving the scapula away from the
midline
• 6.Retraction (Adduction) - moving the scapula toward the
midline