Unilaterally extrapedicular versus transpedicular kyphoplasty in treating osteoporotic lumbar fractures: a randomized controlled study

Background The unilaterally extrapedicular approach is adopted increasingly to perform balloon kyphoplasty in treating osteoporotic lumbar fractures, which is intended to improve radiological and clinical efficacy. We compared the efficacy and safety of this method with a unilaterally transpedicular approach.Methods We conducted a single-center, randomized controlled trial enrolling participants with a one-level osteoporotic lumbar fracture in less than 1 month. Patients were randomly assigned to undergo kyphoplasty via either a unilaterally extrapedicular approach (treatment group) or a unilaterally transpedicular approach (control group). The primary outcome was the difference in change from baseline to 1 month in visual analog scale (VAS) scores between the two groups. Secondary outcome measures included vertebral height ratio, operation time, fluoroscopic times, hemoglobin loss, and cement leakage between groups. Data were analyzed by intention to treat principle.Results A total of 80 participants were assigned to the treatment group (n = 40) and control group (n = 40), with three and two patients lost to follow-up during 12 months in the two groups, respectively. At 1 month postoperatively, the treatment group showed a greater reduction in VAS score from baseline, compared with the control group (mean difference between groups = 0.63, 95%CI 0.19-1.06). There were no significant between-group differences in restoration in anterior, middle, and posterior vertebral body (P > 0.05). No significant differences were found in the rate of cement leakage and perioperative hemoglobin loss (P > 0.05).Conclusion Compared with balloon kyphoplasty via the unilaterally transpedicular approach in treating lumbar OVCFs, the unilaterally extrapedicular approach appears to be promising in achieving effective pain relief, adequate cement infusion, short operation time, less fluoroscopy exposure, and comparable risk of cement leakage and vessel injury. It is an alternative approach for lumbar OVCFs treated with kyphoplasty.