Elbow Joint Functions and Anatomy Quiz

Elbow Joint Functions

• Add mobility of the hand in space
• Shorten or lengthen the arm
• Rotate the forearm
• Provide control and stability for skilled hand motions
• Provide control and stability for forceful upper extremity motions

Elbow Bones

• Upper arm bone: humerus
• Lower arm bones: radius and ulna

Elbow Articulations

• Humeroulnar joint
• Humeroradial joint
• Radioulnar joint
• Ligaments: radial and ulnar collateral ligaments, annular ligament

Elbow Kinematics

• Flexion and extension: humeroulnar joint (hinge), humeroradial joint (gliding)
• Forearm pronation and supination: radioulnar joint (pivot)

Elbow Muscles

• Flexion: biceps brachii, brachialis
• Extension: triceps brachii
• Pronation: pronators
• Supination: supinators

Elbow Structure

• The olecranon process of the ulna provides enough stability and protection for the elbow
• No need for an 'elbow cap' like the patella in the knee

Elbow Kinetics

• Not typically weight-bearing
• High forces during daily activities (e.g. eating, getting up from a chair, pulling a table)
• Higher forces during sports (e.g. baseball pitching, gymnastics)

Elbow Injuries

• Acute injuries: forearm fractures, pain, weakness, swelling, deformity
• Repetitive injuries:
  • Tennis elbow (lateral epicondylitis): repetitive stress on wrist extensor/supinator muscles' tendons
  • Golfer's elbow (medial epicondylitis): repetitive stress on wrist flexor/pronator muscles' tendons
  • Ulnar collateral ligament injury: medial elbow ligament replaced

Shoulder Joint Functions

• Link arms to the trunk
• Add mobility of the arm in space
• Provide control and stability for movements

Shoulder Bones

• Upper arm bone: humerus
• Trunk bones: clavicle, scapula

Shoulder Articulations

• Shoulder joint: glenohumeral joint (reinforced by ligaments)
• Shoulder girdle: armioclavicular joint, sternoclavicular joint, scapulothoracic articulation

Shoulder Kinematics

• Flexion, extension, abduction, adduction, internal rotation, external rotation: glenohumeral joint (ball and socket)
• Shoulder girdle motions: elevation, depression, protraction, retraction
• Scapulohumeral rhythm: regular pattern of scapular rotation accompanying humeral abduction

Shoulder Muscles

• Deltoid: abduction, flexion, extension
• Pectoralis: multiple functions

Test your knowledge on the functions and anatomy of the elbow joint, including its role in hand mobility, arm movements, and stability. Learn about the bones of the elbow (humerus, radius, ulna) and the different articulations like humeroulnar, humeroradial, and radioulnar joints.