Inflammatory pain pattern and pain with lumbar extension associated with Modic 1 changes on MRI: a prospective case-control study of 120 patients.

Purpose: To compare, in a case-control study, clinical characteristics of patients with low back pain (LBP) with and without Modic 1 signal changes on MRI.

Methods: Patients with chronic non-specific LBP and a recent (<6 months) MRI were prospectively screened and included in Modic 1 group or control group. Patients in control group were age- and gender-matched with patients with Modic 1 group. Pain characteristics, including night pain and worse pain on waking and morning stiffness, were recorded. The presence of at least one of these three characteristics indicated an inflammatory pain pattern. Patients were evaluated by questionnaires and physical examination (including lumbar range of motion). Data were analyzed by univariate and multivariate analyses.

Results: 120 patients were included (60 in each group). The groups did not differ in sedentary work (p = 0.25), morning stiffness for >60 min (p = 0.19), waking at night (p = 0.08), worse pain on waking (p = 0.09), back stiffness (p = 0.12), or pain with flexion (p = 0.87). Modic 1 patients more frequently exhibited an inflammatory pain pattern (p = 0.006), worse pain with lumbar extension (p < 0.005) and responded better to oral steroids (p = 0.004) than did controls. On multivariate analysis, Modic 1 changes were associated with sedentary work [odds ratio 0.22 (95% confidence interval 0.05-0.93)], pain with lumbar extension [11.2 (3.1-40.4)] and an inflammatory pain pattern [4.5 (1.2-16.9)].

Conclusions: Characteristics of patients with LBP and Modic 1 changes on MRI consist of an inflammatory pain pattern and pain with lumbar extension. Level of evidence 3b.