The grades of recommendations (standards, guidelines, and options) and classes of evidence (I–III) are defined at the end of the "Major Recommendations" field.
Treatment Standards. There is insufficient evidence to recommend a treatment standard.
Treatment Guidelines. Either direct current stimulation (DCS) or capacitative coupled stimulation (CCS) is recommended as an adjunct to spinal fusion to increase fusion rates in patients who are at high risk for arthrodesis failure following lumbar posterolateral fusion (PLF). Pulsed electromagnetic field stimulation is recommended as an adjunct to increase fusion rates in similar patients treated with lumbar interbody fusion procedures.
Summary
There have been a number of randomized studies supporting the use of electrical stimulation (ES) for the promotion of bone healing following lumbar fusion. All of the published studies have methodological flaws that prevent the studies from providing Class I medical evidence. There is, however, Class II and III evidence to support the use of direct current stimulation or capacitative coupled stimulation for enhancing fusion rates in high-risk patients undergoing lumbar PLF. A beneficial effect on fusion rates in patients not at "high risk" has not been convincingly demonstrated, nor has an effect been shown for these modalities in patients treated with interbody fusion. There is limited evidence both for and against the use of pulsed electromagnetic field stimulation (PEMFS) for enhancing fusion rates following PLF. Class II and III medical evidence supports the use of PEMFS for promoting arthrodesis following interbody fusion. Although some studies have purported to demonstrate functional improvement in some patient subgroups, other studies have not detected differences. All of the reviewed studies are significantly flawed by the use of a four-point patient satisfaction scale as the primary outcome measure. This outcome measure is not validated. Because of the use of this flawed outcome measure and because of the conflicting results reported in the better-designed studies that assess functional outcome, there is no consistent medical evidence to support or refute use of these devices for improving patient outcomes.
Definitions:
Grades of Recommendation
Standards Recommendations of the strongest type, based on Class I evidence reflecting a high degree of clinical certainty
Guidelines Recommendations based on Class II evidence reflecting a moderate degree of clinical certainty
Options Recommendations based on Class III evidence reflecting unclear clinical certainty
Classes of Evidence
Class I Evidence from one or more well-designed, randomized controlled clinical trials, including overviews of such trials
Class II Evidence from one or more well-designed comparative clinical studies, such as nonrandomized cohort studies, case-control studies, and other comparable studies, including less well-designed randomized controlled trials
Class III Evidence from case series, comparative studies with historical controls, case reports, and expert opinion as well as significantly flawed randomized controlled trials
