Efficacy of microcurrent therapy for treatment of acute knee pain: A randomized double-blinded controlled clinical trial.

OBJECTIVE: We would like to determine whether electrotherapy, specifically microcurrent therapy, increases function and decreases pain in people who have acute knee pain. DESIGN: Randomized, double-blinded, placebo-controlled clinical trial. SETTING: University laboratory and patient home. SUBJECTS: A total of 52 subjects (35 females and 17 males) with acute knee pain. INTERVENTION: Treatment group (n = 26) wore the active microcurrent therapy device at home for 3 hours per day for 4 weeks and the control group (n = 26) wore the placebo for 3 hours per day for 4 weeks. MAIN MEASURES: Numeric Pain Rating Scale (NPRS) and Short Form 12 (SF-12) health scale were used to measure the pain level and the functionality of the participants. Secondary assessments included musculoskeletal ultrasound imaging (MSK US) and Lower Extremity Functional Scale (LEFS). RESULTS: A total of 52 subjects completed the study; 26 in the treatment group and 26 in the control group. Microcurrent therapy significantly reduced pain over 4 weeks. Especially week three was significant (P < 0.01) after adjusting for the family-wise error rate. The analysis on SF-12 revealed those with microcurrent therapy showed an increasing trend in the improvement of physical function score until week three. CONCLUSION: An active microcurrent therapy device decreased knee pain and increased function. Microcurrent therapy may be an alternative or used with a pharmacological approach for people with acute knee pain.

On Putting an End to the Backlash Against Electrophysical Agents.

Electrophysical agents (EPAs) are core therapeutic interventions in academic physical therapy curricula around the world. They are used concomitantly with several other therapeutic interventions such as exercise, manual therapy techniques, medications, and surgery for the management of a wide variety of soft tissue disorders. Over the past decade, the practice of EPAs has been the subject of intense scrutiny in the U.S. This has been colored by some physical therapists publicly engaging in bashing rhetoric that has yet to be officially and publicly addressed by the guiding organizations which, together, regulate the practice of physical therapy in this country. Published in world renowned public media are unsubstantiated mocking remarks against the practice of EPAs and unethical allegations against its stakeholders. This rhetoric suggests that EPA interventions are "magical" treatments and that those practitioners who include them in their plans of care may be committing fraud. Such bashing rhetoric is in striking contradiction to the APTA's Guide to Physical Therapist Practice 4.0, which lists EPAs as one of its categories of interventions, the CAPTE's program accreditation policy, and the FSBPT's national licensing exam. The purpose of this commentary is to expose the extent of this discourse and to call to action the APTA, CAPTE, and FSBPT organizations, as well as physical therapists, with the aim at putting an end to this rhetoric.

Use of transcutaneous electrical nerve stimulation along with functional tasks for immediate pain relief in individuals with knee osteoarthritis.

BACKGROUND: Knee pain is the major complaint in individuals with knee osteoarthritis (OA), and the effects of transcutaneous electrical nerve stimulation (TENS) on knee pain are controversial. The present study applied TENS along with functional tests to investigate its effect on pain level in individuals with mild-to-moderate knee OA. METHODS: Twenty volunteers with knee OA classification of graded 2-3 performed four functional tests (stair climb test [SCT], timed up and go test [TUG], 6-minute walk test [6-MWT], knee extensor strength test [KES], and 2-step test from the locomotive syndrome risk test [LSR_2ST]) while wearing either an active or inactive TENS. Knee pain level before and after each test was self-accessed by the Visual Analogue Scale (VAS). The effect of TENS (active vs. inactive) on pain level was submitted to statistical analyses. RESULTS: Knee pain during SCT, TUG, and LSR_2ST tests was significantly lower when subjects used the active TENS, compared with using the inactive unit. The effect of the active TENS on pain level was also more significant in subjects with no anxiety or depression. CONCLUSIONS: The results provided evidence of immediate pain relief in individuals with mild-to-moderate knee OA when TENS is applied along with functional activities, that usually induced pain in people with knee OA. SIGNIFICANCE: The use of transcutaneous electrical nerve stimulation (TENS) in pain management is still unclear. In this study, the analgesic effects of TENS in people with knee osteoarthritis (OA) were found effective when applied along with functional activities. Therefore, study findings provided clinical evidence for the use of TENS during functional activities as a conservative approach to reduce knee OA pain.

A new electrode design to improve outcomes in the treatment of chronic non-healing wounds in diabetes.

BACKGROUND: Chronic wounds are life-threatening in people with diabetes. Some studies show that electrical stimulation (ES) can help wounds heal, while others do not. But, ES is usually applied using a two-electrode system, where current distribution is greatest in the center line between the electrodes. In the present study, a three-electrode system (three-channel ES) was developed. Current dispersion on the skin and in the quadriceps muscle was compared between the conventional two-electrode and three-electrode systems in controls and tested for its ability to heal chronic wounds in people with diabetes. METHODS: In controls, current was delivered via a biphasic sine wave at a frequency of 30 Hz and pulse width of 100 microseconds. Stimulation electrodes 5 cm x 5 cm and 5 cm x 10 cm were placed at 10 cm and 15 cm separation distances above the quadriceps muscle. Skin currents were measured using five pairs of surface electrodes positioned in five separate locations on the skin. Muscle currents were measured using three pairs of needle electrodes positioned in three different locations in the muscle belly. In chronic wounds in eight subjects with diabetes, stimulation was applied for 1 month, and healing and blood flow were measured. RESULTS: Current during three-channel ES was dispersed more evenly and more deeply than with conventional two-channel ES (P < 0.05). In wounds, there was almost complete healing in 1 month, and current was uniform in the wound. CONCLUSIONS: Three-channel ES is more effective than two-channel ES in terms of better current dispersion across the skin and penetration into tissue and will probably be better for wound healing.

The influence of local versus global heat on the healing of chronic wounds in patients with diabetes.

BACKGROUND: In a previous study, it was shown that placing a subject with chronic diabetic ulcers in a warm room prior to the use of electrical stimulation dramatically increased the healing rate. However, global heating is impractical in many therapeutic environments, and therefore in the present investigation the effect of global heat versus using a local heat source to warm the wound was investigated. METHODS: Twenty-nine male and female subjects participated in a series of experiments to determine the healing associated with electrical stimulation with the application of local heat through a heat lamp compared to global heating of the subject in a warm room. Treatment consisted of biphasic electrical stimulation at currents at 20 mA for 30 min three times per week for 4 weeks in either a 32 degrees C room or, with the application of local heat, to raise skin temperature to 37 degrees C. Skin blood flow was measured by a laser Doppler imager. RESULTS: Blood flow increased with either local or global heating. During electrical stimulation, blood flow almost doubled on the outside and on the edge of the wound with a smaller increase in the center of the wound. However, the largest increase in blood flow was in the subjects exposed to global heating. Further, healing rates, while insignificant for subjects who did not receive electrical stimulation, showed 74.5 +/- 23.4% healing with global heat and 55.3 +/- 31.1% healing with local heat in 1 month; controls actually had a worsening of their wounds. CONCLUSIONS: The best healing modality was global heat. However, there was still a significant advantage in healing with local heat.

Enhanced healing of diabetic foot ulcers using local heat and electrical stimulation for 30 min three times per week.

BACKGROUND: Electrical stimulation (ES) with heating is effective in healing chronic wounds. However, it this effect due to ES alone or both heating and ES? The aim of the present study was to deduce the individual roles of heat and ES in the healing of chronic wounds. METHODS: The study was performed on 20 patients (mean age 48.4 ± 14.6 years) with non-healing diabetic foot ulcers (mean duration 38.9 ± 23.7 months) who received local dry heat (37°C; n = 10) or local dry heat + ES (n = 10) three times a week for 4 weeks. Patients were given ES using biphasic sine wave stimulation (30 Hz, pulse width 250 µs, current approximately 20 mA). RESULTS: Skin blood flow in and around the wound was measured with a laser Doppler flow imager. In the ES + heat group, the average wound area and volume decreased significantly by 68.4 ± 28.6% and 69.3 ± 27.1%, respectively (both P < 0.05), over the 1-month period. During the average session, blood flow increased to 102.3 ± 25.3% with local heat and to 152.3 ± 23.4% with ES + heat. In the group receiving treatment with local heat only, wounds that had not healed for at least 2 months showed 30.1 ± 22.6% healing (i.e. a decrease in wound area) after 1 month. Although this level of healing was significant, it was less than that observed in the ES + heat group (P<0.05). CONCLUSIONS: Local dry heat and ES work well together to heal chronic diabetic foot wounds; however, local heat would appear to be a relevant part of this therapy because ES alone has produced little healing in previous studies.

The combined effect of a three-channel electrode delivery system with local heat on the healing of chronic wounds.

BACKGROUND: Historically, electrical stimulation (ES) has been used as a treatment for wound care. However, some studies show wounds healing with ES, whereas others do not. Part of the difficulty can be resolved by using heat to help dilate blood vessels, but an inherent problem with ES is uneven currents across the wound due to the use of only two electrodes. Therefore, we designed and tested a multi-electrode ES device in combination with local warming of the wound in non-healing chronic ulcers. STUDY DESIGN: Eighteen subjects (mean +/- SD age, 35.7 +/- 21.3 years) with chronic ulcers (no healing for 26.1 +/- 24.6 months) received ES treatment three times a week for 4 weeks. A heat lamp was used before and during ES to keep the wound and area surrounding the wound warm (37 degrees C). ES was applied for 30 min with biphasic sine wave stimulation at a frequency of 30 Hz, pulse width of 250 micros, and current of about 20 mA. Skin blood flow (BF) in and around the wound was measured with a laser Doppler imager. Wound size was measured prior to each treatment. RESULTS: Over the 1-month period, the mean wound area significantly decreased by 43.4 +/- 44.5% (P < 0.05), and wound volume decreased by 57.0 +/- 27.9% (P < 0.05). Skin BF significantly increased after application of ES and local heat (P < 0.05). The skin BF response decreased as time progressed and the wound healed. CONCLUSIONS: Thus, in this pilot study, application of a three-channel ES system in combination with local heat is effective in the healing of non-healing chronic wounds. Future studies should examine a larger population with variables such as treatment duration, number of days, or length of treatment to optimize the effect of ES on healing of non-healing chronic wounds.

Estimation of the distribution of intramuscular current during electrical stimulation of the quadriceps muscle.

Electrical stimulation is commonly used for strengthening muscle but little evidence exists as to the optimal electrode size, waveform, or frequency to apply. Three male and three female subjects (22-40 years old) were examined during electrical stimulation of the quadriceps muscle. Two self adhesive electrode sizes were examined, 2 cm x 2 cm and 2 cm x 4 cm. Electrical stimulation was applied with square and sine waveforms, currents of 5, 10 and 15 mA, and pulse widths of 100-500 micros above the quadriceps muscle. Frequencies of stimulation were 20, 30, and 50 Hz. Current on the skin above the quadriceps muscle was measured with surface electrodes at five positions and at three positions with needle electrodes in the same muscle. Altering pulse width in the range of 100-500 micros, the frequency over a range of 20-50 Hz, or current from 5 to 15 mA had no effect on current dispersion either in the skin or within muscle. In contrast, the distance separating the electrodes caused large changes in current dispersion on the skin or into muscle. The most significant finding in the present investigation was that, while on the surface of the skin current dispersion was not different between sine and square wave stimulation, significantly more current was transferred deep in the muscle with sine versus square wave stimulation. The use of sine wave stimulation with electrode separation distances of less then 15 cm is recommended for electrical stimulation with a sine wave to achieve deep muscle stimulation.

A randomized control study on the effect of biphasic electrical stimulation in a warm room on skin blood flow and healing rates in chronic wounds of patients with and without diabetes.

BACKGROUND: Decrease in skin blood flow (BF) due to diabetes may be one reason why only 31% of neuropathic diabetic ulcers heal in 20-weeks. Recent evidence shows that skin blood flow may be increased if therapy is done in a warm room. The purpose of this investigation was to compare healing rates and skin blood flow of chronic stage III and IV wounds in people with diabetes (D) and those without diabetes (WD) using a warm room and electrical stimulation. MATERIAL/METHODS: Twenty subjects with chronic stage III and IV wounds were treated at an outpatient wound center. Ten were D, and ten were WD. Treatment consisted of biphasic electrical stimulation up to 20 ma for 30 minutes, 3 x week for 4 weeks in a 32 degrees C room. Skin blood flow was measured by a Laser Doppler Imager. RESULTS: BF increased not only during the stimulation (the increase in BF was greater for D at 87% than WD at 6%) at the outside of the wound but even at rest before stimulation started after the initial treatment creating a carryover effect. There was no increase in skin blood flow in the center of the wound. Healing rates over four weeks of up to 70% were seen in subjects with diabetes using biphasic current. CONCLUSIONS: Using stimulation in a warm room significantly increased healing and skin blood flow in these wounds.

The thermal effect on the blood flow response to electrical stimulation.

BACKGROUND: Wounds, especially in the elderly, can be life threatening. One modality which allegedly increases blood flow (BF) as an aid to heal chronic wounds is electrical stimulation. This technique applies electrical current (ES) across wounds. However, while many studies show positive findings, others do not. The purpose of this investigation was to investigate some of this inconsistency in results by determining the effect of environmental temperature on the circulation of the skin which may negate the effects of electrical stimulation in a clinical setting. MATERIAL/METHODS: Ten people with no wounds, controls (C), and 12 people with wounds (W) were examined in a thermally neutral or cool room (20 degrees C) and a warm room (34 degrees C) to observe the effect of reducing sympathetic vasoconstrictor activity on the response to 5 and 15 mA sine wave biphasic ES delivered by 2x2 cm surface electrodes. RESULTS: C and W subjects showed a greater BF in the skin in a warm room. In group C, after 30 minutes of stimulation at a current of 15 milliamps, BF increased significantly (p<0.05) but by an average of only 4 flux in the cool room. In the warm environment, BF increased significantly (p<0.01) by 19.3+/-7 flux and increased further during the 60 minute recovery phase. In the W group, BF during ES increased much more during stimulation in a warm room compared to a cool room. CONCLUSIONS: The results show that local vasoconstriction due to exposure to a warm global temperature greatly increases the response of the skin the ES.