Contents
Definition
Inflammatory back pain is among the common symptoms that lead to spondyloarthritis og Ankylosing spondylitis/Ankylosing spondylitis. However, only about 30% of such symptoms develop such a disease (reference: Wang R, 2018). Thus, the benefit (specificity is low but sensitivity is high) is less than previously thought (reference: de Hooge M, 2019); Poddubnyy D, 2018). The criteria for inflammatory back pain are therefore not suitable for making such a diagnosis without additional studies involving a thorough clinical examination, MR and HLA-B27 in the blood.
Symptoms
Inflammatory back pain versus mechanical (degenerative) back pain (Duba AS, 2018):
| Inflammatory back pain | Mechanical back pain | |
| Age at onset | <40 years | All ages |
| Morning stiffness | >60 minutes | <30 minutes |
| Nocturnal pains | Common | Absent |
| Effect of physical activity/exercise | Improvement | Aggravation |
Criteria for inflammatory back pain
There are at least three versions of criteria for inflammatory back pain: Calin A, 1977, Rudwaleit M, 2006 and ASAS IBP (Sieper J, 2009). These are largely overlapping and include: Symptom onset before the age of 40, duration at least 3 months, improvement in physical activity, no relief from rest, night pains that are relieved when one gets up and moves.
Rudwaleit's definition has the highest specificity (81%, sensitivity 70%) and is reproduced below:
Inflammatory back pain (reference: Rudwaleit M, 2009):
- Morning stiffness in the back for at least 30 minutes
- Improvement by physical activity, not to be at rest
- Wake up in the second half of the night because of pain
- Alternating pelvic pain (gluteal)
Two sets of criteria for inflammatory back pain;
| Calin A criteria 1977 (5 out of 5: Sens 95%, Specs 85% for Ankylosing spondylitis) | Sieper J criteria 2009 (4 of 5: sens. 77%, spec. 91,7% for axial SpA) |
| Debut at the latest at the age of 45 | Debut under the age of 40 |
| Morning stiffness at least 30 minutes | Pain at night |
| Improvement by physical activity | Improvement by physical activity |
| Gradual debut | Gradual debut |
| Duration for at least 3 months | No improvement from rest |
Literature
Spondyloarthritis, BINDEVEVSSYKDOMMER.no
Gran's compendium in rheumatology
