Fusion success and clinical outcome were determined in 48 high-risk patients who underwent posterolateral lumbar fusions with internal fixation and were treated with adjunctive pulsed electromagnetic field (PEMF) stimulation postoperatively. An independent radiographic assessment demonstrated a success rate of 97.9%. Following treatment, 59% of the working patients returned to their employment. Overall clinical assessment was excellent in 4.2% of patients, good in 79.2%, and fair in 16.7%; no patient had a poor clinical assessment.