Upper Extremity - Hand, Wrist & Forearm Radiographic Anatomy

Upper Extremity - Hand, Wrist & Forearm Radiographic Anatomy

Course Information

  • Course: Anatomy & Physiology 1 ANAT 1015
  • Institution: Loyalist College of Applied Arts & Technology

Radiographic Anatomy Review

  • Phalanges

    • PIP Joints: Proximal Interphalangeal joints - articulation between the head of the proximal phalanx and the base of the middle phalanx.
    • DIP Joints: Distal Interphalangeal joints - articulation between the head of the middle phalanx and the base of the distal phalanx.

  • Metacarpals

    • MCP Joints: Metacarpophalangeal joints - articulation between the heads of metacarpal bones and the bases of proximal phalanges.
    • CMC Joints: Carpometacarpal joints - articulation between distal carpal bones and metacarpals.

  • Carpal Bones

    • Mnemonic: So Long To Pinky, Here Come The Thumb
    1. Scaphoid
    2. Lunate
    3. Triquetrum
    4. Pisiform
    5. Trapezium
    6. Trapezoid
    7. Capitate
    8. Hamate

  • Radius/Ulna

    • Proximal Radioulnar Joint: Articulation between the radial head and the radial notch on the ulna.
    • Distal Radioulnar Joint: Ulnar notch on the radius articulates with the ulnar head.
    • Radiocarpal Joint: Articulation of the scaphoid, lunate, and triquetrum with the radius and the articular disk just distal to the ulna.

Required Readings

  • Anatomy & Physiology: Openstax College, Rice University, Chapter 8, Section 8.2 “Ulna-Phalanx”
  • Merrill’s Atlas of Radiographic Positioning and Procedures: Chapter 5, pages 143-146

Learning Objectives

  • To identify and describe the bones of the hand, wrist, and forearm radiographically.
  • To locate and describe the articulations of the hand, wrist, and forearm radiographically.
  • To describe the rotational movement of the forearm as it appears in a radiographic image.

Key Terms

  • Olecranon: Bony prominence of the elbow, located at the proximal end of the ulna.

  • Coronoid Process: Hooked projection of bone located on the ulna.

  • Trochlear Notch: Large depression located on the proximal end of the ulna that receives the trochlea of the humerus.

  • Radial Styloid Process: Bony projection found on the lateral aspect of the distal radius.

  • Radial Tuberosity: Oval eminence on the medial aspect of the radius, just distal to the neck, where the biceps muscle attaches.

Hand Joints

PIP Joint
  • Formed by the head of the proximal phalanx and the base of the middle phalanx.
DIP Joint
  • Formed by the head of the middle phalanx and the base of the distal phalanx.
IP Joint
  • Interphalangeal joint of the first digit (thumb), formed by the head of the proximal phalanx and the base of the distal phalanx.
MCP Joint
  • Formed by the head of the metacarpal bone and the base of the proximal phalanges.

Anatomical Considerations in Hand (1st Digit)

  • Distal Phalanx: The bone at the end of the finger.
  • Proximal Phalanx: First bone of the finger leading to the MCP joint.
  • Interphalangeal (IP) Joint: Joint between the two phalanges of the thumb.
  • MCP Joint: Joint connecting the metacarpal to the first phalanx.

Anatomical Considerations in Hand (2nd-5th Digits)

  • Distal Phalanx: Each finger ends in a distal phalanx.
  • Middle Phalanx: Found in each finger except the thumb.
  • Proximal Phalanx: Connects each middle phalanx with a metacarpal.
  • MCP Joint: Similar to the first digit, but doesn't include the thumb.

Hand (Pediatric Development)

  • Examined on a developmental basis (1 year, 3 years, 6 years, 12 years).

Wrist Anatomy

Carpometacarpal Joints (CMC)
  • Distal carpal bones articulate with metacarpal bones.
Intercarpal Joints
  • Articulation between carpal bones.
Radiocarpal Joint
  • Articulation of the scaphoid, lunate, and triquetrum with the radius and the articular disk just distal to the ulna.
Wrist Movements
  • Radial Deviation: Movement towards the radius.
  • Ulnar Deviation: Movement towards the ulna.

Carpal Sulcus

  • Contains the median nerve and flexor retinaculum, affecting the carpal tunnel and associated syndromes.

Forearm Anatomy

Proximal Radioulnar Joint
  • Radial head articulates with the radial notch on the ulna.
Distal Radioulnar Joint
  • Ulnar notch on the radius articulates with the ulnar head.
Supination and Pronation of the Arm
  • Supination: Palm facing anteriorly.
  • Pronation: Palm facing posteriorly. Visual views represent these positions in radiographic imaging.

Key Takeaways

  • Properly identifying bony markings is crucial for accurate positioning in radiographic imaging.
  • Joint spaces must be clearly visualized and assessed in images to ascertain health.
  • Pediatric radiographic imaging reveals growth patterns associated with age.

References

  • Betts, J. G., Young, K. A., Wise, J. A., Johnson, E., Poe, B., Kruse, D. H., Korol, O., Johnson, J. E., Womble, M., & DeSaix, P. (2022, April 20). 1.6 Anatomical Terminology - Anatomy and Physiology 2E | OpenStax. https://openstax.org/books/anatomy-and-physiology-2e/pages/1-6-anatomical-terminology
  • Rollins, J. H., & Curtis, T. (2025). Merrill’s Atlas of Radiographic Positioning and Procedures - Volume 1. Elsevier