Distribution of Arthritis in the Hands

• In rheumatoid arthritis, the "proximal" areas of the hand (those closest to the wrist) tend to be more heavily affected, along with those of the wrist itself, while in osteoarthritis the more "distal" joints of the fingertips are involved. Arthritis appears on radiographs as swollen areas of bone or as holes in the bone called "erosions."
  
  

Scoring

• As early as the 1970s, different scoring systems were developed for determining the extent of joint damage observed in X-ray images. These scores were intended to correlate with projected joint function and clinical outcome. Today, computer software processes images automatically, producing scores that are intended to be less susceptible to user bias.
  
  

Subtle Differences

• Although radiology is a standard technique is the diagnosis of arthritis, the differences between arthritis types can be subtle and other techniques are in use or under development as well. These include magnetic resonance imaging (MRI) and ultrasound.