Three-year follow-up of lumbar artery occlusion with magnetic resonance angiography in patients with sciatica: associations between occlusion and patient-reported symptoms.

STUDY DESIGN

Comparison of occlusion of lumbar arteries in magnetic resonance angiography (MRA) with patient-reported sciatica symptoms during a 3-year follow-up.

OBJECTIVES

To evaluate whether occlusion of lumbar arteries is associated with subjective pain symptoms and physical ability among sciatica patients.

SUMMARY OF BACKGROUND DATA

Cadaveric studies indicate that atherosclerotic manifestations of the abdominal aorta are associated with low back pain (LBP). Impaired blood flow may disturb diffusion of nutrients into the disc, causing degeneration and possibly back pain.

METHODS

Two-dimensional time-of-flight MRA was used to evaluate lumbar arteries at baseline and 3 years. The arteries on both sides (L1-L4) were evaluated visually and scored as normal, narrowed, or occluded. Incidence of new stenosis was estimated. The associations of stenosis with self-reported previous medical consultations, pain duration through the first year, and number of pain episodes through the last 2 years of follow-up were calculated. Additionally, leg and back pain (10-cm VAS), disability (Oswestry), and self-reported physical ability (self-efficacy) were inquired at 1, 2, and 3 years. In the statistical analysis, bivariate correlation, and the chi or Fisher's test were used.

RESULTS

MRA was obtained at baseline for 147 patients and at 3 years for 134 patients. Baseline stenosis associated with intensity of back pain at 1 year, leg pain at 2 years, and self-efficacy at every follow-up assessment, but not with disability, previous LBP history, or future pain episodes. The associations of stenosis at 3 years were similar but weaker. Newly formed stenosis was associated with the preceding year's medical consultations due to LBP and prolonged LBP during the first follow-up year.

CONCLUSIONS

Arterial stenosis is associated strongly and consistently with patient-estimated physical ability,but only slightly with subjective pain symptoms. Interestingly, new stenosis is preceded by pain symptoms. The evaluation of lumbar blood flow may thus be useful in clinical practice.