Table 1.
Compatible Additive MRI scale.
| Joint characteristic | Points* |
|---|---|
| Synovial hypertrophy | |
| Small | 1 |
| Moderate | 2 |
| Large | 3 |
| Haemosiderin | 1 |
| Changes of subchondral bone or joint margins | |
| Any surface erosion | 1 |
| Any surface erosion in at least 2 bones | 1 |
| Half or more of the articular surface eroded in at least 1 bone | 1 |
| Half or more of the articular surface eroded in at least 2 bones | 1 |
| At least 1 subchondral cyst | 1 |
| More than 1 subchondral cyst | 1 |
| Subchondral cysts in at least 2 bones | 1 |
| Multiple subchondral cysts in each of at least 2 bones | 1 |
| Cartilage loss | |
| Any loss of joint cartilage height | 1 |
| Any loss of joint cartilage height in at least 2 bones | 1 |
| Any loss of joint cartilage height involving more than one-third of the joint surface in at least 1 bone | 1 |
| Any loss of joint cartilage height involving more than one-third of the joint surface in at least 2 bones | 1 |
| Full-thickness loss of joint cartilage in at least some area in at least 1 bone | 1 |
| Full-thickness loss of joint cartilage in at least some area in at least 2 bones | 1 |
| Full-thickness loss of joint cartilage involves at least one-third of the joint surface in at least 1 bone | 1 |
| Full-thickness loss of joint cartilage involves at least one-third of the joint surface in at least 2 bones | 1 |
*
Maximum value: 20 points.
Adapted from Lundin et al. Compatible scales for progressive and additive MRI assessments of haemophilic arthropathy. Haemophilia 2005;11:109–115. Reprinted with permission.