Joints of the Upper Limb Quiz

Joints of the Upper Limb

• Joints of the upper limb are divided into two groups: girdle joints and joints of the movable part.

Sternoclavicular Joint

• Synovial articulation between the sternal end of the clavicle and clavicular notch of the sternal manubrium.
• Saddle, multiaxial joint.
• Contains an articular disc.
• Ligaments:
  • Sternoclavicular anterior and posterior ligaments (capsular)
  • Interclavicular ligament (capsular)
  • Costoclavicular ligament (extracapsular)

Acromioclavicular Joint

• Synovial articulation between the acromial end of the clavicle and acromion of the scapula.
• Gliding, multiaxial joint.
• Ligaments:
  • Acromioclavicular ligament (capsular)
  • Coracoclavicular ligament (extracapsular), divided into two parts: trapezoid ligament and conoid ligament, attached to the clavicle.

Shoulder - Glenohumeral Joint

• Synovial articulation between the head of the humerus and glenoid cavity of the scapula.
• Ball and socket, multiaxial joint.
• Additional elements:
  • Glenoid labrum, which surrounds the glenoid fossa.
  • Four bursae associated with this joint: subscapular bursa, subdeltoid bursa, subacromial bursa, and subcoracoid bursa.
• Ligaments:
  • Coracohumeral ligament
  • Glenohumeral superior, middle, and inferior ligaments (capsular)
• Tendon of the long head of the biceps brachii muscle passes through the joint cavity.
• Glenohumeral dislocations:
  • The glenohumeral joint is the most mobile but least stable joint in the body, and dislocations are frequent.
  • Rotator cuff muscles provide stability, but inferior support is lacking.
  • Majority of dislocations (90%) occur inferiorly, often labeled as “anterior” dislocations based on the position of the humeral head relative to the glenoid. These injuries can damage the axillary nerve and lead to a flattened shoulder profile.

Bursae

• Sac-like structures present in some synovial joints.
• Located between:
  • Muscle and bone
  • Tendon and bone
  • Ligament and bone
• Function:
  • Reduce mechanical friction between two structures relative to each other.
  • Example: between bone and extracapsular ligaments.