Effects of transforaminal balloon treatment in patients with lumbar foraminal stenosis: a randomized, controlled, double-blind trial.

BACKGROUND Lumbar spinal stenosis is a common condition in the elderly. Although balloon treatment is a well-known therapeutic method in specific pain conditions, applying the balloon treatment in patients with lumbar spinal stenosis is not yet well established. OBJECTIVES We tested the therapeutic effect of transforaminal balloon treatment with a Fogarty balloon catheter on body pain and functional performance in patients with severe lumbar spinal stenosis. STUDY DESIGN Prospective, randomized, double-blinded, active control trial. SETTING A tertiary, interventional pain management practice, specialty referral center. METHODS Sixty-two patients with refractory unilateral radiculopathy aggravated by walking were enrolled and randomly assigned to receive transforaminal steroid injection after transforaminal balloon treatment using a 3 Fr balloon catheter (n = 32) or the same procedure without balloon treatment (n = 30). The patients were prohibited from making any alterations to their medications during the 12 weeks of their follow-up period. After the first 12 weeks, the patients who had persistent symptoms or unbearable pain were allowed to increase the dose of analgesics or to receive additional interventional treatment. OUTCOME ASSESSMENT Visual analogue scale (VAS) pain scores for the leg and lower back, Oswestry disability index (ODI), and claudication distance were measured at 2, 4, 8, and 12 weeks post procedure. During the 52 weeks of the overall follow-up period, the patients achieving ≥ 50% leg pain relief without additional treatment or increasing the dose of analgesics were evaluated. RESULTS Significant improvement occurred compared to baseline in VAS (P < 0.001), ODI (P < 0.001), and claudication distance (P < 0.001) in the balloon group during the overall follow-up period, whereas the improvement in ODI (P < 0.05) and claudication distance (P < 0.05) in the control group persisted for 8 weeks. The balloon group showed better improvement in leg VAS (P < 0.05), ODI (P < 0.05), and claudication distance (P < 0.05) than the control group at all post-procedure assessment points. Kaplan-Meier analysis of the duration of the patients achieving ≥ 50% leg pain relief without additional treatment or increasing the dose of analgesics showed a significant intergroup difference between the balloon and control (P = 0.003) groups. Six patients (18.8%) in balloon group maintained ≥ 50% pain relief for 52 weeks whereas no patient (0%) did in control group. LIMITATIONS Our study is an active-controlled randomized design with a relatively small number of patients. CONCLUSION Transforaminal balloon treatment leads to both significant pain relief and functional improvement in a subset of patients with refractory spinal stenosis. INSTITUTIONAL REVIEW: This study was approved by the Institutional Review Board of the Asan Medical Center.