6 randomized controlled trials evaluating the use of electrical stimulation techniques in patients undergoing lumbar spinal fusion surgery were included in this systematic review. The purpose of this systematic review was to assess the effectiveness of various electrical stimulation techniques in promoting bone fusion/union following lumbar spinal fusion procedures in comparison to a control group without stimulation. The types of electrical stimulation techniques included direct current, pulsed electromagnetic field, and capacitive coupling stimulation. Regardless of the type of electrical stimulation technique used, the overall proportions of patients achieving bony fusion/union varied widely (35.4-90.6%) and were comparable to control values over 9-24 month follow-up periods. The overall strength of the evidence used in this review was rated as 'low' using the GRADE system.