Skip to main content


Table 1 Rationale for variables

From: Do MRI findings identify patients with chronic low back pain and Modic changes who respond best to rest or exercise: a subgroup analysis of a randomised controlled trial

Modic changes Type 1 (compared with not having Type 1)
 The histology of Type 1 shows fissured endplates and vascular granulation tissue adjacent to the endplate [7] and could potentially be an early state of bone healing. Therefore, we hypothesised that patients with Modic changes Type 1 would benefit more from rest than from exercise, as rest would facilitate bone healing compared with the compression forces added from exercise.
Large modic changes (compared with small ones)
 Kuisma et al. [26] found that extensive Modic changes (≥25 % of vertebral height) were associated with a higher pain score in a working population. Large Modic changes could represent larger disruptions of the endplate and vertebral body and might therefore signal a better outcome from rest than from exercise.
Large modic changes Type 1 (compared with not having this finding)
 Based on the hypotheses mentioned above for Modic type and size, we expected that people with large Modic changes Type 1 would benefit more from rest than from exercise.
Severe disc degeneration (compared with not having this finding)
 Hancock et al. [27] reported that disc degeneration grade of ≥3 (Pfirrmann grade 1–5) was more than 5 times more likely to be present in patients with acute LBP than in controls without current LBP. Severe disc degeneration and mild disc degeneration could respond differently to conservative treatment. However, the available evidence does not clearly indicate a direction of a potential subgroup effect. Patients with severe disc degeneration could benefit from exercise due to the overall positive effects of physical activity. On the other hand, exercise could lead to increased load on a degenerated joint which could potentially result in a negative outcome.
Large disc herniation (compared with not having this finding)
 Patients with LBP and sciatica receiving active conservative treatment [28] who also had broad-based protrusions and extrusions (‘large’ herniations) had a better outcome in leg pain and physical function than patients with disc bulges or focal protrusions. However, the evidence is sparse and it is possible that ‘large’ herniations could benefit either from the general effects of exercise or from less load with rest.