Larsen score of joint involvement by rheumatoid arthritis on plain radiographs
Larsen's scoring system atributes 0 to 5 points to each synovial joint evaluated on a radiograph. As each synovial joint can be included in the score, description of scored joints and maximum attainable score should be reported.
The original method from 1977 included hands, wrists, and feet with a maximum possible score of 250 (10 joints per hand or foot + 2 x 5 x wrist) x 5. The wrist is considered as one unit and the score is multiplied by five:
- 5 distal interphalangeal joints (DIP)
- 4 proximal interphalangeal joints (PIP)
- 5 metacarpophalangeal joints (MCP)
- wrist as one unit (score multiplied by 5)
- 5 metatarsophalangeal joints (MTP)
- Interphalangeal joint of halux
per one hand or foot.
| Points | Description |
|---|---|
| 0 | normal |
| 1 | slight abnormalities (periarticular soft tissue swelling and periarticular osteoporosis, slight joint space narrowing) |
| 2 | definite early abnormalities |
| 3 | medium destructive abnormalities |
| 4 | severe definite abnormalities |
| 5 | mutilating abnormalities |
The 1995 revision omitted thumbs and first metatarsophalangeal joint (MTP). The wrist was subdivided into four quadrants:
- 2nd to 5th proximal interphalangeal joint (PIP)
- 2nd to 5th metacarpophalangeal joint (MCP)
- four quadrants in the wrist
- 2nd to 5th metatarsophalangeal joints (MTP)
in each foot or hand. The score ranges between 0 and 160.
| Points | Description |
|---|---|
| 0 | Intact bony outlines and normal joint space |
| 1 | Erosion less than 1 mm in diameter or joint space narrowing |
| 2 | One or several small erosions, diameter more than 1 mm |
| 3 | Marked erosions |
| 4 | Severe erosions, where there is usually no joint space left, and the original bony outlines are partly preserved |
| 5 | Mutilating changes, where the original bony outlines have been destroyed |
References:
1. O’Sullivan MM, Lewis PA, Newcombe RG, Broderick NJ, Robinson DA, Coles EC, et al. Precision of Larsen grading of radiographs in assessing progression of rheumatoid arthritis in individual patients. Ann Rheum Dis. 1990 May;49(5):286–9.
2. Larsen A, Dale K, Eek M. Radiographic evaluation of rheumatoid arthritis and related conditions by standard reference films. Acta Radiol Diagn (Stockh). 1977 Jul;18(4):481–91
3. Boini S, Guillemin F. Radiographic scoring methods as outcome measures in rheumatoid arthritis: properties and advantages. Ann Rheum Dis. 2001 Sep 1;60(9):817–27.
4. Larsen A. How to apply Larsen score in evaluating radiographs of rheumatoid arthritis in long-term studies. J. Rheumatol. 1995 Oct;22(10):1974–5.