The Association Between Conditioned Pain Modulation and Pain Catastrophizing in Chronic Low Back Pain

The Efficiency of Conditioned Pain Modulation is Associated With Levels of Pain Catastrophizing in Patients With Chronic Low Back Pain

This study evaluates the potential association between pain catastrophizing thoughts and the ability to dampen pain via endogenous descending inhibition. Half of the participants are persons with chronic low back pain and the other half are age and gender-matched controls

Pain catastrophizing is a cognitive feature commonly seen in various musculoskeletal pain population and is considered an important factor to account for in rehabilitation. The ability to dampen pain via endogenous pain modulatory mechanisms is likewise known to be reduced in musculoskeletal pain conditions.

Studies utilizing functional magnetic resonance imaging (fMRI) have demonstrated that the supraspinal areas involved in pain-related cognitive processing to a great extent overlap with those involved in endogenous pain modulation. Therefore, it is plausible that factors such as pain catastrophizing thoughts may affect the nervous systems ability to dampen pain.

Chronic low back pain is the single clinical problem with the biggest impact in the modern society. Previous studies have demonstrated that pain catastrophizing and reduced endogenous pain inhibition are part of the clinical picture. However, previous studies have never investigated a potential relationship between these two factors.

Inclusion Criteria:

Low back pain group:

• chronic low back pain ( lasting more than 3 months)
• intensity of ≥ 3/10 on a numeric rating scale
• pain is located in the area between the gluteal folds below to the thoracolumbal junction above.

Controls:

No current or previous history of musculoskeletal pain of ongoing nature

Exclusion Criteria:

Applies for both groups:

• Signs of radicular pain or other specific medical conditions e.g. rheumatologic disease or diabetes
• Pregnancy