Patient selection: rheumatoid arthritis
Joint selection:
(1) distal articular radius
(2) distal articular ulna
(3-5) second, third and fifth metacarpophalangeal (MCP)
(6-7) second and third proximal interphalalangeal
(8-9) first and fifth metatarsophalangeal (MTP)
Method:
(1) Each joint was examined proximally and distally to the joint margin.
(2) Each surface was scanned in quadrants (dorsomedial, volar/plantar medial, volar/plantar lateral, dorsolateral).
total number of surfaces scanned =
= 9 * 2 = 18
total number of quadrants scanned =
= 18 * 4 = 72
total number of quadrants scanned if left and right sides performed =
= 2 * 72 = 144
Percent of Quadrant with Erosions
|
Points for the Quadrant
|
0
|
0
|
less than third
|
1
|
one to two thirds
|
2
|
greater than two thirds
|
3
|
score for proximal joint =
= SUM(points for the 4 quadrants) / 4
score for distal joint =
= SUM(points for the 4 quadrants) / 4
Interpretation:
• minimum score for joint: 0
• maximum score for joint: 3
• The diameter of the largest erosion was recorded for each of the 9 joints as MAX(transverse diameter, longitudinal diameter).