Quiz 3 Flashcards
Which wrist bone is most commonly fractured?
scaphoid
Which wrist bone is most commonly dislocated?
lunate
What is the sternoclavicular joint? Which ligaments stabilize and prevent excessive movement of it?
The sternoclavicular joint is:
- a fairly stable modified saddle joint
- Convex medial end of clavicle fits into concave manubrium.
- Fibrocartilagenous disc separates the articulating surfaces
- The sternoclavicular ligaments bind the clavicle to the manubrium on both anterior and posterior surfaces.
- The interclavicular ligament binds the medial ends of the right and left clavicles to each other just above the manubrium
- The costoclavicular ligament binds the clavicle to the first rib
What do the sternoclavicular ligaments do?
Part ofthe sternoclavicular joint, the sternoclavicular ligaments bind the clavicle to the manubrium on the anterior and posterior surfaces
What does the interclavicular ligament do?
Part of the sternoclavicular joint, the interclavicular ligament binds the medial ends of the right and left clavicles to each other just above the manubrium.
What does the costoclavicular ligament do?
The costoclavicular ligament binds the clavicle to the first rib in the sternoclavicular joint
Under which ligament can a branch of the brachial plexus get trapped? What happens as a result?
The costoclavicular ligament. It results in pain and muscle weakness, depending upon which branch is trapped.
Are dislocations of the sternoclavicular joint common? What results if there is a posterior dislocation?
No, they are not common. Posterior dislocation can result in trauma to the brachiocephalic veins that are located just posterior to this joint.
What innervates the sternoclavicular joint?
The nerve to the subclavius and the supraclavicular nerve
What supplies the blood to the sternoclavicular joint?
the suprascapular or internal thoracic arteries supply the blood to the sternoclavicular joint
What movements are associated with the sternoclavicular joint?
The sternoclavicular joint increases shoulder ROM and passively moves with scapular motion
Describe the acromioclavicular joint.
- -Synovial joint of Planar type between acromion of scapula and lateral end of clavicle.
- some movement here, but the main function is to bind the clavicle to the scapula in order to support the weight of the upper limb and keep the humerus suspended at the side without using a lot of muscle contraction energy.
What is the main function of the acromioclavicular joint?
bind the clavicle to the scapula in order to support the weight of the upper limb and keep the humerus suspended at the side without using a lot of muscle contraction energy
What provides the main stabilizing force to the acromioclavicular joint?
ligaments.– the acromioclavicular ligament that binds the clavicle to the acromion and the coracoclavicular ligaments, which bind the coracoid process of the scapula to the clavicle.
What two ligaments make up the coracoclavicular ligament?
the conoid and the trapezoid ligaments
When does shoulder separation occur? Describe shoulder separation.
When there is tearing of the coraclavicular ligaments and/or the acromioclavicular ligaments. A greater tear results in greater separation from the clavicle. When this happens, the weight of the upper limb pulls the scapula and the acromion downward. The result is that the clavicle overrides the acromion.
What is the innervation of the acromioclavicular joint?
suprascapular and lateral pectoral nerves
What is the blood supply of the acromioclavicular joint?
suprascapular and thoracoacromial arteries
Describe the glenohumeral joint.
- Most mobile joint in the human body.
- ball and socket synovial joint between head of humerus and concave glenoid fossa of the scapula.
- fibrous capsule that attached from the glenoid cavity to the anatomical neck of the humerus surrounds the joint.
- ligaments reinforce the capsule in all directions except for the inferior portion.
What are the ligaments that reinforce the glenohumeral joint?
1) coracoacromial ligament (which doesn’t actually attach to this joint) connects the coracoid process to the acromion. It reinforces the superior aspect of the shoulder joint and helps prevent upward displacement of the head of the humerus.
2) Coracohumeral ligament– strengenths the superior portion of the capsule and helps resist excessive abduction. It runs from the coracoid process to the lesser tubercle.
3) the transverse humeral ligaments holds the tendon of the long head of the biceps in the bicipital groove. This stabilizes the tendon so that it doesn’t pop out.
4) 3 parts of the glenohumeral ligament, which attach from the upper margin of the glenoid cavity and labrum, strengthen the anterior portion of the capsule.
Ligaments reinforce the fibrous capsule that attaches from the glenoid cavity to the anatomical neck of the humerus in all directions except?
inferior portion
What are the three parts of the glenohumeral ligament?
1) The superior part, which runs over the humeral head to a depression above the lesser tuberosity.
2) The middle part, which runs from in front of the humerus to lower lesser tuberosity
3) the inferior part, which runs to a lower part of the anatomical neck. This ligament is a key stabilizer of the anterior shoulder.
Weakness of which part of the glenohumeral ligament often leads to anterior glenohumeral instability?
The inferior part
What is the glenoid labrum?
rim of fibrocartilage attaching to the outer rim of the glenoid fossa. Superior attachment of the labrum includes the supraglenoid tubercle and the origin of the tendon of the long head of the biceps.