Effects of smoking and maturation on long-term maintenance of lumbar spinal fusion success

This is a follow-up study of a multicenter, randomized, placebo-controlled clinical trial conducted in accordance with the condition for Food and Drug Administration approval for pulsed electromagnetic fields. The purpose of this study was to evaluate the long-term efficacy and safety of pulsed elec tromagnetic fields for spinal fusion. An earlier clinical trial study was c onducted to evaluate the efficacy of Pulsed Electromagnetic Fields to enhan ce fusion success at one year follow-up. In the original study, 195 patient s undergoing interbody fusion were enrolled. Of the 195 patients, 98 were i n the active group and 97 were in the placebo group. Study results Bowed a 92% successful fusion rate in the active group compared to 68% in the place bo group. For this long-term follow-up study, all patients who had healed i n the original study were recalled for a follow-up radiograph. Radiographs were assessed by the attending surgeon for fusion assessment, when possible . The results of this long-term follow-up study showed that there was a red uction in maintenance of the fusion over time by 25%, but that the reductio n was unrelated to treatment group and correlated statistically with whethe r the patient was a smoker.