EFFECT OF PULSED ELECTROMAGNETIC FIELD ON THE CONSOLIDATION OF POSTEROLATERAL ARTHRODESES IN THE LUMBOSACRAL SPINE: A PROSPECTIVE, DOUBLE-BLIND, RANDOMIZED STUDY

ABSTRACT Objective: To assess the effect of pulsed electromagnetic field (PEMF) on the consolidation of instrumented lumbar posterolateral arthrodeses in patients who have been surgically treated for degenerative spine disease. Methods: Forty cases were recruited from 163 consecutive patients undergoing lumbar arthrodesis at the same center. The patients were randomized into two groups of 20 patients: Active Group, who were exposed to PEMF for 4 hours a day for 90 days after surgery, and Inactive Group, who received an identical device, with the same instructions for use but without the ability to generate PEMF. The patients underwent computed tomography scans at 45, 90, 180 and 360 days after surgery to check for the occurrence of arthrodesis at each operated spinal level. Results: In the course of the study, two patients were excluded from each group. There were no significant differences between the groups with respect to age, gender, smoking habit, or the number of vertebral levels included in the arthrodesis. The percentage of consolidation of the vertebral levels increased at 90, 180 and 360 days compared to 45 days (p<0.001) in both groups. The Active Group had a 276% greater chance of consolidation in the vertebral levels (OR = 3.76; 95% CI: 1.39-10.20), regardless of the time of evaluation. Patients in the Active Group presented 16% more consolidation than patients in the inactive group (p=0.018). Conclusions: Post-operative exposure to PEMF following instrumented arthrodesis of the lumbar spine for degenerative spine disease increased consolidation in the first year after surgery.

摘要
【研究目的】评估脉冲电磁场（pulsed electromagnetic field, PEMF）对退行性脊柱疾病患者行后路腰椎融合内固定术后骨融合效果的影响。
【研究方法】本研究从同一中心163例行腰椎融合术的连续性患者中纳入40例，将其随机分为两组，每组各20例：实验组（Active Group）于术后每日接受PEMF治疗4小时，持续90天；对照组（Inactive Group）使用同款设备，遵循相同使用指导，但设备无法产生PEMF。分别于术后45、90、180及360天对患者行计算机断层扫描（computed tomography, CT），以检测各手术脊柱节段的融合发生情况。
【研究结果】本研究过程中，每组各排除2例患者。两组患者在年龄、性别、吸烟史及融合节段数量方面均无显著差异。相较于术后45天，两组患者在术后90、180及360天的椎体融合率均显著升高（p<0.001）。无论评估时间如何，实验组患者的椎体融合几率较对照组高276%（比值比（Odds Ratio, OR）=3.76；95%置信区间（Confidence Interval, CI）：1.39~10.20）。实验组患者的融合率较对照组高16%（p=0.018）。
【研究结论】针对退行性脊柱疾病行腰椎后路融合内固定术后，术后应用PEMF可提升术后1年内的骨融合效果。