Functional Anatomy of the Elbow

Functional Anatomy of the Elbow Lab

Overview of Elbow Joint

• Composition of Elbow Joint: 3 bones
  • Humerus
  • Radius
  • Ulna

Mnemonics for Radius Position

• Trick to Remember Radius Position:
  • Correlate with thumb position using "Radio antenna with thumb" = radial side.

Elbow Joints

• Types of Elbow Joints: 3 specific joints
  • Humeroulnar Joint
  • Humeroradial Joint
  • Proximal Radioulnar Joint

Ligaments of the Elbow

• Ligaments Resisting Valgus Forces:
  • Ulnar Collateral Ligament
• Ligaments Resisting Varus Forces:
  • Radial Collateral Ligament

Unique Ligament

• Annular Ligament:
  • Unique feature: Surrounds the neck of the radius.

Force Distribution

• Interosseous Membrane Purpose:
  • Helps distribute forces from distal radius throughout the rest of the arm.

Planes of Motion

• Pronation and Supination Plane:
  • Occurs in the transverse plane.
• Elbow Flexion and Extension Plane:
  • Occurs in the sagittal plane.

Muscle Groups of the Elbow

• Anterior Muscles of the Elbow:

  • Biceps Brachii
  • Brachialis
  • Brachioradialis
  • Pronator Teres

• Posterior Muscles of the Elbow:

  • Triceps Brachii
  • Anconeus

Motion Produced by Muscles

• Common Motion by Anterior Muscles:
  • Flexion of the elbow.
• Common Motion by Posterior Muscles:
  • Extension of the elbow.

Carrying Angle

• Definition of Carrying Angle:
  • Angle between the humerus and forearm observed in the frontal plane.

Cubitus Varus vs. Cubitus Valgus

• Cubitus Valgus:
  • Defined as an angle larger than the normal range.
• Cubitus Varus:
  • Defined as an angle smaller than the normal range.

Anatomical Landmarks of the Humerus

• Label the Following Bones (Anterior View):

  • Humerus
  • Coronoid Fossa
  • Medial Epicondyle
  • Lateral Epicondyle
  • Trochlea
  • Capitulum
  • Shaft

• Label the Following Bones (Posterior View):

  • Humerus
  • Olecranon Fossa
  • Medial Epicondyle
  • Lateral Epicondyle
  • Trochlea
  • Capitulum
  • Shaft
  • Radial Groove

Anatomical Landmarks of the Radius

• Label the Following Bones (Anterior View):

  • Radius
  • Head
  • Neck
  • Radial Tuberosity (or Tubercle)
  • Styloid Process
  • Ulnar Notch

• Label the Following Bones (Posterior View):

  • Dorsal Tubercle
  • Ulnar Notch
  • Radial Tuberosity

Anatomical Landmarks of the Ulna

• Label the Following Bones (Posterior View):
  • Ulna
  • Olecranon Process
  • Trochlear Notch
  • Coronoid Process
  • Radial Notch
  • Head
  • Styloid Process

Ligament Identification

• Find the Following Ligaments on the Visible Body App:
  • Ulnar (Medial) Collateral Ligament
  • Anterior Band
  • Posterior Band
  • Transverse Band
  • Radial (Lateral) Collateral Ligament
  • Lateral Ulnar Collateral
  • Radial Collateral
  • Accessory Lateral Collateral Ligaments
  • Annular Ligament

Muscle Matrix

• Fill in the Matrix Below:
  | Name | Origin | Insertion | Action | Nerve Innervation |
  |--------------------|-------------------------------|----------------------------------|------------------------------------|-------------------|
  | Biceps Brachii | Ridge of Humerus | See Shoulder Lab | Elbow Flexion | Musculocutaneous |
  | Brachioradialis | Supracondylar process | Elbow Flexion | Radial |
  | Brachialis | Anterior lower coronoid | Asst. Pronation + Supination | Musculocutaneous |
  | Pronator Teres | Medial Epicondyle | Middle Radius | Pronation | Median |
  | Triceps Brachii | See Shoulder Lab | Olecranon Process | Elbow Extension | Radial |
  | Anconeus | Lateral Epicondyle | Olecranon | Elbow Extension | Radial |