Electrical Stimulation for the Treatment of Arthritis
Electrical stimulation has been used to improve functional status and relieve pain related to osteoarthritis and rheumatoid arthritis unresponsive to other standard therapies. Noninvasive electrical stimulators generate a weak electrical current within the target site using pulsed electromagnetic fields, capacitive coupling, or combined magnetic fields. In capacitive coupling, small skin pads/electrodes are placed on either side of the knee or wrist. Electrical stimulation is provided by an electronic device that noninvasively delivers a sub-sensory low-voltage, monophasic electrical field to the target site of pain. Pulsed electromagnetic fields are delivered via treatment coils that are placed over the skin. Combined magnetic fields deliver a time-varying magnetic field by superimposing the time-varying magnetic field onto an additional static magnetic field.
In basic research studies, pulsed electrical stimulation has been shown to alter chondrocyte-related gene expression in vitro and to have regenerative effects in animal models of cartilage injury. Therefore, pulsed electrical stimulation is proposed to be similar to bone stimulator therapy for fracture nonunion. Electrical bone growth stimulation of the appendicular skeleton is addressed in a separate policy. (See Related Policies).
The FDA’s 510(k) summaries specify the BioniCare Stimulator, Model Bio-1000™ is indicated for use as an adjunctive therapy in reducing the level of pain and:
The BioniCare system is contraindicated in patients with demand-type pacemakers and may interfere with other electronic devices.
Medical policies are systematically developed guidelines that serve as a resource for Company staff when determining coverage for specific medical procedures, drugs or devices. Coverage for medical services is subject to the limits and conditions of the member benefit plan. Members and their providers should consult the member benefit booklet or contact a customer service representative to determine whether there are any benefit limitations applicable to this service or supply. This medical policy does not apply to Medicare Advantage.
Interpretation of evidence regarding treatments for arthritis can be confounded by many factors, including the natural variation of disease remission and progression in individual patients and subjective reporting. Therefore, evidence from large, rigorously designed randomized controlled trials (RCTs), ideally observed over an extended period of time, is needed to adequately assess electrical stimulation outcomes. The study selection criteria outlined in a 1996 TEC Assessment on transcutaneous electrical nerve stimulation (TENS), as follows, may be applied (1):
To date, 3 small RCTs with pulsed electrical stimulation (BioniCare) and 3 RCTs with pulsed electromagnetic field therapy (Diatermed II and Palermo) have been identified.
Pulsed Electrical Stimulation (BioniCare)
Randomized Controlled Trials
In 1995, Zizic et al. reported a multicenter, double-blind, randomized, placebo-controlled trial of pulsed electrical stimulation to assess pain relief and functional improvements in 78 patients with osteoarthritis of the knee. (1) Patients used the BioniCare or placebo device for 6–10 hours daily for 4 weeks and were allowed to continue nonsteroidal anti-inflammatory drug (NSAID) therapy. The placebo group used a dummy device that initially produced a sensation like the BioniCare device. Both patient groups were instructed to dial down the level to just below the sensation threshold. In the placebo group, the device would soon turn itself off. The primary outcomes assessed at baseline and after 4 weeks of treatment included patient assessment of pain and function and physician global evaluation of the patient’s condition. The authors reported that the BioniCare group had statistically significant improvement, defined as improvement of 50% or greater, in each of the primary outcomes assessed. The authors also assessed 6 secondary outcomes including duration of morning stiffness, range of motion, knee tenderness, joint swelling, joint circumference, and walking time. However, only a decrease in mean morning stiffness in the BioniCare group was statistically significant. While this study reports short-term improvements with pulsed electrical stimulation using the BioniCare device, the authors note that long-term studies are warranted. In addition to longer term studies, larger studies would also be beneficial. The Zizic et al. trial was included in a 2002 Cochrane review of electromagnetic fields for the treatment of osteoarthritis (2) that concluded there may be some benefit, but further studies are needed. The Cochrane review also noted that the Zizic et al. trial was rated as high-quality, but it did not describe the randomization process; it was funded by the manufacturer, and it did not focus on outcomes of clinical significance.
An industry-sponsored, randomized, double-blind sham-controlled study of the BioniCare pulsed electrical stimulation device for 58 patients with osteoarthritis of the knee was reported in 2007. (3) Due to protocol violations from one of the centers (other new treatments were provided during the study) an additional 42 subjects were excluded from the analysis. Patients were instructed to wear the devices for 6 hours or more each day (typically at night), and compliance, which was monitored with a timer in the device, was found to be similar in the 2 groups (63% to 66% of patients, respectively). At the end of 3 months of use, the percentage of patients who improved 50% or more was greater with the active device group for patient global (39% vs. 5%, respectively), patient pain (44% vs. 16%, respectively), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain (39% vs. 11%, respectively) subscales. The percentage of patients who improved 50% or more on the WOMAC stiffness (28% vs. 5%, respectively) and WOMAC function (23% vs. 5%, respectively) subscales showed the same trend but did not reach statistical significance in this sample. As indicated, longer-term larger controlled comparative studies are needed to evaluate this device.
In 2011, Fary et al. reported results from a randomized double-blind sham-controlled trial of pulsed electrical stimulation in 70 patients with osteoarthritis of the knee. (4) The device used in this study was a commercially available TENS (transcutaneous electrical nerve stimulator) unit that was modified to provide pulsed electrical stimulation. Participants were instructed to apply the device for a minimum of 6 hours a day. In the placebo group, the device turned itself off after 3 minutes. After 26 weeks of treatment, 59% of patients using the active device and 36% of controls had achieved target usage based on patient-maintained logs. Intention-to-treat analysis showed a statistically significant improvement in visual analog score (VAS) for pain over 26 weeks in both groups, but no difference between groups (VAS of 20 vs. 19 for controls on a 100-mm scale). There was no significant difference between groups in the proportion of patients who achieved a clinically relevant 20-mm improvement in VAS pain score at 26 weeks (56% vs. 44% of controls). There were no significant differences between groups for changes in WOMAC pain, function, and stiffness scores, short-form 36 (SF-36) physical and mental component summary scores, patient's global assessment of disease activity, or activity measures.
Data on treatment of rheumatoid arthritis of the hand using the BioniCare device were presented to the American College of Rheumatology in November 2005. (5) The presentation reported on a double-blind placebo-controlled trial of 89 patients with rheumatoid arthritis in which statistically significant improvements in patient assessment of pain, symptoms, and function and physician global evaluation of the patients' condition were seen after 4 weeks of treatment. However, this study is not published, and longer term, larger studies appear to be needed based on the information presented.
Non-randomized Controlled Trials
Reported in 2006 was a non-randomized study of pulsed electrical stimulation in 157 patients (recruited from 23 centers) with moderate to severe knee osteoarthritis who had received a recommendation for total knee arthroplasty (TKA). (6) Patients were instructed to use the electrical stimulation device for 6 to 10 hours per day. The time to TKA was compared to a historical matched (age, gender, and weight) control group of 101 knee osteoarthritis patients treated at one of the centers. Analysis showed that 60% of patients in the electrical stimulation group had deferred TKA at 4 years, compared with 35% in the historical control group. Interpretation is limited due to the potential for higher motivation to avoid TKA in the subjects who agreed to participate in the study.
Results of a 4-year study of the BioniCare device in 150 patients with moderate to severe knee osteoarthritis who were candidates for TKA were described in a poster presentation at the 2004 American Academy of Orthopaedic Surgeons’ annual meeting. (7) The poster presenters reported that patients using the BioniCare device avoided TKA over 50% of the time (p=0.0004) at 1-, 2-, 3-, and 4-year follow-up when compared to a matching group of 101 patients. Study patients who avoided surgery also reported “significant improvements in pain scores (mean 40%), function (mean 38%), and physician global evaluation (mean 38%).” This study’s design fails to meet the study selection criteria outlined here in that it did not have a randomly assigned control group.
In 2006, the BioniCare manufacturer published data on 288 patients with knee osteoarthritis treated with the BioniCare device in an open-label prospective study. (8) The study participants experienced improvements in patient assessment of pain and global evaluation of disease activity and physician global evaluation of the patients' condition. In addition, 45.4% reduced their use of NSAIDs by 50% or more. However, this study did not have a randomly assigned control group.
Pulsed Short-wave Electromagnetic Field Stimulation (Diatermed II and SofPulse™)
In 2011, Fukada et al. reported a double-blinded RCT from South America that included 121 women who were divided into 4 groups, low (19 min treatment) or high-dose (38 min treatment) short-wave electrical field stimulation with a Diatermed II (9 sessions over 3 weeks), placebo, or no-treatment control. (9) Pain and function were measured with a numeric rating scale (NRS) and the Knee Osteoarthritis Outcome Score (KOOS) at baseline, immediately after treatment, and at 1-year follow-up. Except for the untreated controls, both patients and the physical therapist evaluator were blinded throughout the 1-year follow-up. When measured immediately after treatment, both the low and high-dose groups showed significantly greater improvement than the control groups in the numeric rating scale and KOOS subscales. For example, the NRS decreased from 7.7 to 6.9 in the placebo group, from 7.1 to 3.8 in the low-dose group, and from 6.7 to 4.6 in the high dose group. The percentage of patients who attained the minimal clinically important difference of 2 points on the NRS was 15% in the control group, 15% in the placebo group, 75% in the low-dose group, and 50% in the high-dose group. At the 1-year follow-up the low-dose group, but not the high-dose group, significant improvement remained on 3 of 5 KOOS subscales. Since there was a 36% dropout rate (from patients lost to follow-up, patients who received other therapies, and patients who had a total knee replacement), analyses were performed both per-protocol and by last observation carried forward; these analyses yielded similar results.
A 2010 double-blind randomized controlled trial from Turkey investigated the effect of pulsed electromagnetic field therapy (PEMF) in 40 patients with knee osteoarthritis. (10) Patients with an average pain intensity of 40 or more on a 100-mm visual analog scale (VAS) were randomly assigned to receive PEMF or sham PEMF in addition to their physical therapy. Sessions included 20-min hot pack, 5-min ultrasound, and 30-min PEMF or sham and were provided 5 times per week for 2 weeks, along with isometric knee exercises performed at home. After 2 weeks, both groups showed improvement in pain and functional scores; there were no significant differences between the 2 groups.
Nelson et al. reported a well-conducted, randomized, double-blind, placebo-controlled pilot study with the Palermo device in 34 patients with osteoarthritis. (11) In addition to having knee pain with confirmed articular cartilage loss and an initial VAS score of 4 or more, only patients who had at least 2 h of daily standing activity in a physical occupation were included in the study. Patients were instructed to use the electromagnetic device for 15 min twice daily, and the total number of sessions used was recorded by the device. An average 80 of 84 possible sessions were recorded. Patients were asked to self-report the maximum daily VAS pain score on a 10 cm line for weeks 1 and 2, and then for weeks 5 and 6. By the end of the study, 3 active and 7 sham patients had dropped out of the study due to a lack of perceived benefit. At baseline, there was no significant difference in VAS between the active (6.8) and sham (7.1) treatment groups. Using intent-to-treat analysis with last observation carried forward, the average decrease in VAS was 2.7 in the active treatment group (statistically significant) and 1.5 in the sham group (not statistically significant). By the end of the study, the maximum VAS decreased by 39% in patients receiving the active treatment and 15% in the sham group. The difference between groups (4.19 vs. 6.11) was statistically and clinically significant.
OrthoCor™ Active Knee System
No RCTs with the OrthoCor Active Knee System were identified.
A review of the literature has not found adequate evidence to indicate the use of pulsed electrical stimulation for the treatment of arthritis will result in improvements in health outcomes. For osteoarthritis of the knee, only 2 small published randomized controlled trials using the BioniCare device and 1 randomized trial with a customized device, and 3 randomized trials with electromagnetic devices were identified. These trials have methodologic limitations and have reported mixed results. Short-term benefit was reported in the 2 BioniCare studies, but in the third trial that used a customized device and had the longest follow-up, pulsed electrical stimulation was no more effective than placebo at 26 weeks. No published studies of pulsed electrical stimulation for rheumatoid arthritis were identified. Results from studies of 3 different electromagnetic devices are also mixed, and efficacy reported in the trials varied by the specific device used. The most convincing evidence to date is from a pilot study of the Palermo device with a relatively small number of patients. Additional study with a larger number of subjects is needed.
This evidence remains insufficient to evaluate the effect of this treatment on health outcomes. Therefore, pulsed electrical stimulation is considered investigational for the treatment of osteoarthritis and rheumatoid arthritis.
Medicare National Coverage
There is no national coverage determination (NCD). In the absence of an NCD, coverage decisions are left to the discretion of local Medicare carriers.
Transcutaneous electrical joint stimulation device system, includes all accessories
Type of Service
Durable Medical Equipment
Place of Service
New policy. Add to Durable Medical Equipment section. Removed from 1.01.507.
Update Coding Section – ICD-10 codes are now effective 10/01/2014.
Replace policy. A literature review through August 2012 resulted in no revision to the rationale section and no additions to the references section. Minor edits for readability. The policy statement of investigational is unchanged.
Update Related Policies. Add 2.01.31.
Replace policy. No new references added. No change to policy statement. CPT Code 64550 added to policy.
Annual Review. Regulatory Status section updated with 3 additional electrical stimulation devices. Policy updated with a literature review through October 2014. References 1, 10-12 added; others renumbered. Policy statement unchanged. ICD-9 and ICD-10 codes removed, along with CPT 64550; these are not utilize in adjudication of the policy.
Disclaimer: This medical policy is a guide in evaluating the medical necessity of a particular service or treatment. The Company adopts policies after careful review of published peer-reviewed scientific literature, national guidelines and local standards of practice. Since medical technology is constantly changing, the Company reserves the right to review and update policies as appropriate. Member contracts differ in their benefits. Always consult the member benefit booklet or contact a member service representative to determine coverage for a specific medical service or supply. CPT codes, descriptions and materials are copyrighted by the American Medical Association (AMA).