Type 1 Modic changes was a significant risk factor for 1 year outcome in sick-listed low back pain patients: a nested cohort study using magnetic resonance imaging of the lumbar spine

Abstract

BACKGROUND CONTEXT:

It is not clear whether Modic changes (MC) is associated with low back pain (LBP) outcome.

PURPOSE:

To study associations between baseline degenerative manifestations and outcome in sick-listed LBP patients.

STUDY DESIGN:

Prospective nested cohort study based on a randomised controlled trial.

PATIENT SAMPLE:

Out of 325 sick-listed LBP patients, 141 patients were consecutively examined by magnetic resonance imaging (MRI) and included, and 140 patients completed the study.

OUTCOME MEASURES:

Degenerative manifestations of the lumbar spine were quantified, and associations were studied in relation to the three primary outcomes 1) change of back+leg pain and 2) change of function as measured by Roland-Morris questionnaire and 3) one-year U-RTW.

METHODS:

By using a previously validated MRI-protocol, a specialist in radiology, who had no access to clinical data, described the images. Associations were studied by linear and logistic regression with adjustment for previously identified prognostic factors for one-year pain and function and for unsuccessful return to work (U-RTW).

RESULTS:

Clinically, 43% of the patients had radiculopathy. Degenerative changes were prevalent with altered disc contours in 84%, high intensity zones in 70% and nerve root touch or impingement in 63% of the patients. MC was identified in 60% of the patients, 18% with type 1 changes and 42% with type 2 changes, type 1 including both type 1 and type 1 in combination with type 2. Patients with type 1 changes reported more back pain and did not improve in pain or disability. They increased to include 30% of the patients with U-RTW at one year. Patients with type 2 changes did not differ significantly from patients without MC, but differed significantly from patients with type 1 changes in all three outcomes. Other degenerative manifestations were not significantly associated with any of the three outcomes.

CONCLUSIONS:

The only degenerative manifestation negatively associated with outcome was type 1 MC which affected 18% of the cohort at baseline and implied an increased risk for no improvement in pain and function and for U-RTW, even after adjustment for other prognostic factors.

Copyright © 2014 Elsevier Inc. All rights reserved.

KEYWORDS:

Low back pain, Modic changes, disc herniation, prognosis, return to work, sick-listing

PMID:

 

24534386

 

[PubMed - as supplied by publisher]