Imaging Anatomy
Table of Contents


  • A joint refers to the articulation between two bones
  • Joints can be described by the intrinsic components connecting the bones which in turn determines the degree of motion across that joint:
    • Fibrous
      united by fibrous tissue, limited motion, e.g. sutures skull vault
    • Cartilaginous
      • Primary - united by a plate of cartilage, no motion, e.g. a growth plate, costochondral joint
      • Secondary - bone ends covered by hyaline cartilage with intervening fibrocartilage plate, limited motion, e.g. symphysis pubis
    • Synovial
      bone ends covered with hyaline cartilage and separated by a joint cavity containing a synovial membrane. Allows the widest range of motion across a joint.

Illustration of a Synovial Joint

  • Note the opposing articular cartilage which are radiolucent on radiograph and account for the apparent joint space on X-rays. Deep to the cartilage is the subchondral bone plate.
  • The bare area is at the periphery of the joint space and represents that portion of intra-articular bone covered by a synovial membrane but without the protective covering of articular cartilage.
  • Marginal erosions occur at the bare area.
PA radiograph of 2nd DIPJ , the joint space (arrow) represents for the most part the radiolucent articular cartilage. The subchondral bone plate lies deep to the cartilage (line)
Magnified MCPJ, 1-Cortex, 2 & 4-Subchondral bone plate, 3- Joint space, 5-Bare area

Joints of the Hand

  • The joints of the hand and wrist are synovial joints and include the following:
Distal radioulnar joint Brown
Radiocarpal joint Yellow
Intercarpal joints Green
Carpometacarpal joints Blue
Metacarpophalangeal joints Pink
Proximal Interphalangeal joints Dark Yellow
Distal Interphalangeal joints Red

Bones of the Hand

3-D CT of the Hand

Press play to rotate

Test Youself

Describe the 3 provided radiographic views and naming the individual joints and bones