Iontophoresis

Iontophoresis is commonly used in physical therapy practice as an alternative to oral or injection methods of drug delivery. Electrostatic repulsion is the driving force behind this modality. Common indications for iontophoresis are pain, inflammation, edema, calcium deposits, and hyperhidrosis. Generally, results should be achieved within 4-5 treatments and there must be at least 24-48 hour separation between each treatment.

Article for Ionophorsis

The study by Melson.,et al. (2011) examined the effectiveness of dexamethasone iontophoresis for temporomandibular joint involvement in juvenile idiopathic arthritis. There were twenty-eight patients used in this study between the ages of two and twenty-one years old. They received dexamethasone iontophoresis for the temporomandibular joint an average of eight sessions. This type of iontophoresis used low-grade electric currents to deliver dexamethasone into the temporomandibular joint. One TMJ measurement (in mm) examined was the maximal interincisal opening (MIO) which is the distance between the upper and lower incisor during full mouth opening with head in neutral. The other measurement (in mm) was the maximum lateral excursion (MLE) which is the horizontal distance measured between the upper and lower central incisors with movement of the mandible to the left or right side. Both measurements used the TheraBite range of motion scale and were measured before and after treatment.

 After accessing the patient’s records, 28 of the patients had serial MIO measures and only 16 of the 28 had serial MLE measurements. The median increase in MIO measurement was 4.5 mm and 2.25 mm for the MLE measurement. There were 19 of the 28 patients (68%) that saw an increase in their MIO measurement, and there were 11 of the 16 patients (69%) that saw in increase in their MLE measurement. Also, 15 of the 28 patients reported that they had pain in their TMJ joint when they were chewing or they were at rest, which was resolved in 11 of the patients with the use of dexamethasone iontophoresis. There were 1/3 of the 28 patients that saw no improvements. Overall, the article shows that dexamethasone iontophoresis is effective for treating temporomandibular joint limitations in juvenile arthritis patients.

In the study Physical Therapist Management of an Adult with Osteochondritis Dissecans of the Knee by Michael P Johnson, interventions for OCD were evaluated and followed up nine months after the treatment. The patient was a twenty-four year old female who was diagnosed using MRI. During therapy, she was educated on minimizing loading across the knee, performed strengthening exercises, and received iontophoresis. Iontophoresis was applied to anteromedial condyle of the femur using 4mg/mL solution of DEX-P. After five treatment sessions, the patient reported 0/10 knee pain and only reported slight pain with palpation. At the nine month follow-up, the patient reportedly had 95% of prior knee function and no pain during daily activities or palpation.

In a study by Sreerekha et al, the use of dexamethasone to suppress the histamine-induced wheal was examined. They compared dexamethasone delivered by iontophoresis and without iontophoresis (topical).  Twenty volunteers were used. Each volunteer had a dexamethasone soaked gauze piece placed on each forearm, one connected to the iontophoretic machine and one not. Electric current was delivered for 15 minutes with amperage according to patient tolerance. Prick testing was done with histamine solution at the end of 30 minutes, 1 hour, and 2 hours. The wheal diameter on the arm that used iontophoresis was lower and statistically different than the other at the end of 30 minutes. At the end of 1 and 2 hours there was no statistically significant difference in wheal suppression. This study found iontophoresis to be more effective in suppressing the histamine wheal at the end of 30 minutes, but the effect decreases at the end of 1 hour. It was also concluded that dexamethasone administered using iontophoresis is more effective than dexamethasone without iontophoresis.
 

Article Against Iontophoresis

 In a study by Cleland., et al. (2009) the effectiveness of manual therapy and exercise was compared to the effectiveness of electrophysical agents and exercise for the management of plantar heel pain. There were 54 subjects in this study between the ages of 18 and 60 that had a primary complaint of plantar heel pain. There were six therapists involved in this study that received standardized training by one of the investigators. Each patient was seen a total of 6 times over a period of 4 weeks. The patients were divided into two groups (27 people in each): manual physical therapy and exercise (MTEX) and electrophysical agents and exercise (EPAX). The MTEX group received 5 minutes of aggressive soft tissue mobilizations that were directed at the triceps surae, insertion of plantar fascia, and rearfoot eversion. They also received impairment based physical therapy for hip, knee, ankle, and foot. They also were given a home exercise program that included gastroc and soleus stretches. The EPAX group received ultrasound for five minutes followed by iontophoresis with dexamethasone. They then were given stretches for the gastroc, plantar fascia, and soleus along with intrinsic foot strengthening exercises. 

The results were measured using the LEFS (lower extremity functional scale), the FAAM (the foot and ankle ability measure), and the NPRS (the numeric pain rating scale). The patients were examined at baseline, 4 weeks, and 6 months. For the LEFS and FAAM tests the MTEX group had better measures than the EPAX group at both the 4 week and 6 month follow up appointments. Also The MTEX groups had a much larger NPRS improvement than the EPAX group at the 4 week follow up appointment, but by 6 weeks there as not a significant difference between the groups. The results show that MTEX is a better choice than EPAX for the management of plantar heel pain. This means that ultrasound and dexamethasone iontophoresis with exercise are not the most effective choice when compared to manual therapy and exercise.

Amirjani et al conducted a study evaluating the effectiveness of dexamethasone iontophoresis as a noninvasive method of treating carpal tunnel syndrome. Subjects in the treatment group received 0.4% dexamethasone sodium phosphate dissolved in distilled water, whereas the placebo group received distilled water. The delivery electrode was placed directly over the carpal tunnel, and each patient received 6 treatments (on alternate days over a 2-week period) of a dose of 80 mA/min at a rate of 2 mA/min. Baseline measures were repeated at monthly intervals after treatment for a total of 6 months. Most of the outcome measures were not shown to have any significant change after treatment. This study found that although iontophoresis of 0.4% dexamethasone is well-tolerated by patients, it was not effective in the treatment of moderate carpal tunnel syndrome.

In a study A systematic review and meta-analysis of clinical trials on physical interventions for lateral epicondylalgia by Bisset L, Paungmali A, Vicenzino B, and Beller E, the effectiveness of treatment for lateral epicondylagia was evaluated. Twenty eight randomized controlled trials met the minimum criteria for meta-analysis. Iontophoresis was evaluated using a control group receiving saline and the experimental group receiving a corticosteroid solution. After one to three months of treatment, significant results were not found in the experimental group.

Chelsea K., Kelci M., Shannon L.

References

Mina, R., Melson, P., Powell, S., Rao, M., Hinze, C., Passo, M., et al. (2011). Effectiveness of Dexamethasone Iontophoresis for Temporomandibular Joint Involvement in Juvenile Idiopathic Arthritis. Arthritis Care & Research, 63(11), 1511-1516. doi:10.1002/acr.20600 

Cleland, J., Abbot, J., Kidd, M., Stockwell, S., Cheney, S., Gerrard, D., et all. (2009) Manual Physical Therapy and Exercise Versus Electrophysical Agents and Exercise in the Management of Plantar Heel Pain: A Multicenter Randomized Clinical Trial. Physical Therapy, 39(8), 573-585. doi:10.2519/jospt.2009.3036

Amirjani, N., Ashworth, N. L., Watt, M. J., Gordon, T., & Chan, K. M. (2009). Corticosteroid iontophoresis to treat carpal tunnel syndrome: a double-blind randomized controlled trial. Muscle & nerve, 39(5), 627-33. doi:10.1002/mus.21300 

Sreerekha, Rai R, Shanmuga SV, Karthick, Prabhu S, Srinivas CR, Mathew AC. Study of histamine wheal suppression by dexamethasone with and without iontophoresis. Indian J Dermatol Venereol Leprol 2006;72:283-5 

Johnson, Michael P. "Physical Therapist Management of an Adult With Osteochondritis Dissecans of the Knee." Journal of the American Physical Therapy Association 85.7 (2005): 665-75. Physical Therapy. Web. 05 Mar. 2012. <http://ptjournal.apta.org/content/85/7/665.long>.

Bisset, L., Paungmali, A., Vicenzino, B., & Beller, E. (2005). A systematic review and meta-analysis of clinical trials on physical interventions for lateral epicondylalgia. British Journal of Sports Medicine, 39(7), 411-422. doi: 10.1136/bjsm.2004.016170

Russian Electrical Stimulation

The Russian protocol is a modality of electrical stimulation that has been employed for muscle strengthening.  It was originally developed for strengthening of Russian Olympic athletes by Yadou Kots.  This type of electrical stimulation is a medium frequency polyphasic AC waveform with burst modulations.  There are typically 50 bursts per second with 50 pulses per burst.  The application is 10 seconds on, 50 seconds off, for a duration of 10 minutes.  The intensity is adjusted to elicit a tetanic contraction and is usually uncomfortable to the patient.  There are several studies to indicate that this protocol may have some benefit in muscle strengthening.  However, there are studies which also indicate that adjustments can be made to the original work of Kots which may be more appropriate and comfortable.

Articles Refuting Russian Electrical Stimulation

In an article by Alex Ward, Electrical stimulation using kilohertz-frequency alternating current, the effects of burst-modulated alternated currents were reviewed.  Russian current is a type of burst-modulated alternating current that has been claimed to be beneficial for muscle strengthening.  A single case study demonstrated significant strength gains with this protocol; however, there was also one study did not demonstrate any strength gains.  In the study reporting strength gains, the parameters were 2.5 kHz AC applied in 10 millisecond bursts with a frequency of 50 Hz and 10 seconds on followed by 50 seconds off.  Later studies have shown that short duration bursts are more comfortable for the same force output. The author concluded that the parameters used for Russian protocol are suboptimal for strengthening.  Parameters that might be more beneficial would include a shorter duration of 2-4 millisecond burst of kilohertz AC.  The author recommends a frequency of 1 to 2.5 kHz with a burst duration of 2 milliseconds for maximum muscle torque production.   

According to the article: The effect of duty cycle and frequency on muscle torque production using kilohertz frequency range alternating current. by Ward et al. there are suggested optimal parameters for Russian e-stim when it comes to subject comfort and subject maximal torque production. In regards to maximal torque production, the article suggests the best results are seen with a duty cycle of 20% or less, as compared to the more commonly adhered to 50% duty cycle setting, which is popular in many clinics. When comfort is taken as priority a frequency of 2.5 kHz is optimal, but for maximum torque production, 1 kHz should be considered.

In the study, Effect of Burst Frequency and Duration of Kilohertz-Frequency Alternating Currents and of Low-Frequency Pulsed Currents on Strength of Contraction, Muscle Fatigue, and Perceived Discomfort, the authors set out to determine if Russian electrical stimulation elicited a greater strength of muscle contraction than low frequency pulsed currents (LPC). This study showed no difference in the force of the contractions elicited by the LPC or Russian stimulation but the LPC fatigued muscles less. This study also showed no difference in the amount of discomfort experienced by patients when using either the LPC or Russian stimulation.

 

Sources: 

Ward, A. R. (2009). Electrical stimulation using kilohertz-frequency alternating current. Physical therapy, 89(2), 181-90. doi:10.2522/ptj.20080060

Ward, A. R., Robertson, V. J., & Ioannou, H. (2004). The effect of duty cycle and frequency on muscle torque production using kilohertz frequency range alternating current. Medical engineering & physics, 26(7), 569-79. doi:10.1016/j.medengphy.2004.04.007

Laufer, Yocheved, and Michal Elboim. "Effect of Burst Frequency and Duration of Kilohertz-Frequency Alternating Currents and of Low-Frequency Pulsed Currents on Strength of Contraction, Muscle Fatigue, and Perceived Discomfort ." Journal of the American Physical Therapy Association. 88.10 (2008): 1167-76. Web. 2 Mar. 2012. <http://ptjournal.apta.org/content/88/10/1167.long>.

 
Articles Supporting Russian Electrical Stimulation

 The study, Torque responses in human quadriceps to burst-modulated alternating current at 3 carrier frequencies, examined the effects of frequency of burst-modulated current on the electrically induced torque of the quadriceps femoris muscle.  The researchers used three groups to compare frequencies of 2500 Hz, 3750 Hz, and 5000 Hz.  It was found that the electrically induced torque measures of the 2500 Hz frequency group were significantly greater than the 3750 Hz and 5000 Hz groups.  Clinically, this information can be used on healthy subjects who are able to tolerate high stimulation intensities.  The 2500 Hz frequency is more beneficial in generating greater electrically induced torques which is useful if strengthening is the goal of therapy.

In the article Interferential and burst-modulated biphasic pulsed currents yield greater muscular force than Russian current, by Bellew et al. Russian current was compared to interferential and burst-modulated biphasic pulsed currents to determine which method of electrical stimulation could produce the most amount of muscle force/torque by eliciting knee extension. The parameter of pulse duration was kept constant with each method, with a setting of 200 microseconds. Russian was delivered at 2500 Hz, burst modulated at 50 Hz, using 10msec burst duration and 10msec interburst interval. Biphasic pulsed was a symmetrical biphasic square wave delivered in bursts at 50 Hz. Quad IFC was delivered using currents of 2500 and 2550 Hz, yielding a 5050 Hz beat frequency.  Treatments were administered 1 week from each other, and performed using optimal electrode placement. Results were compared with each healthy subjects’ previously recorded maximal voluntary isometric contraction (MVIT), showing that biphasic pulse, interferential, and Russian elicited 62.5%, 66.1%, and 35.8% of MVIT respectively. Therefore using the same pulse duration, Russian elicited significantly less torque and muscle force than biphasic pulsed, and interferential treatments.

In the article, Strength Changes in the Normal Quadriceps Femoris Muscle as a Result of Electrical Stimulation, the authors set out to find if Russian electrical stimulation alone could increase muscle strength.  They used three experimental groups: a control group which did not exercise, a group that did an isometric workout, and a group that received Russian electrical stimulation. This study found that both the isometric and the electrical stimulation groups had a 2% increase in strength compared to the control group after a 5 week long program.

 Sources

Parker, M. G., Keller, L., & Evenson, J. (2005). Torque responses in human quadriceps to burst-modulated alternating current at 3 carrier frequencies. The Journal of orthopaedic and sports physical therapy, 35(4), 239-45. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/15901125

Bellew, J. W., Beiswanger, Z., Freeman, E., Gaerte, C., & Trafton, J. (2011). Interferential and burst-modulated biphasic pulsed currents yield greater muscular force than Russian current. Physiotherapy theory and practice. doi:10.3109/09593985.2011.637286

 Laughman, R. Keith, James Youdas, Tom Garrett, and Edmund Chao. "Strength Changes in the Normal Quadriceps Femoris Muscle as a Result of Electrical Stimulation." Journal of the American Physical Therapy Association. 63.4 (1983): 494-5. Web. 2 Mar. 2012. <http://www.physther.net/content/63/4/494.full.pdf>.

Angie M., Luke G., and Ethan Q.

Neuromuscular Electrical Stimulation (NMES)

The approach that our group took was to find articles that dealt with the use of NMES for the rehabilitation of various impairments or deficits that occur after a person has had a stroke.  Neuromuscular Electrical Stimulation (NMES) is the application of an electrical stimulus to a group of muscles, most often for the purpose of rehabilitation.  The intent of NMES is to use electrical impulses to stimulate nerves in target muscles in order to try and “retrain” them to function properly again.  Below we have provided articles that both support and refute the use NMES as an effective rehabilitation modality for stroke patients.

Articles Supporting NMES

               In the study of Mesci, Ozdemir, and Kabayel et al., the researchers wanted to examine the effectiveness of Neuromuscular Electrical Stimulation (NMES) on chronic stroke patients who were receiving rehabilitation on their lower extremities.  This study was a randomized single blind controlled trial that that involved 40 chronic stroke patients.  The patients were randomly assigned to either the treatment (NMES) group or the control group.  All patients received a conventional rehabilitation program for a 4-week period; in addition the treatment group received NMES treatment (for 4 weeks, 5 days a week) for hemiplegic foot dorsiflexor muscles (Mesci et al., 2009).  Pre-treatment and post-treatment evaluations showed a significant increase in ankle dorsiflexion and a significant decrease in the level of spasticity in the treatment group when compared to the control group.  Overall, this study found that the use of NMES in hemiplegic foot dorsiflexion can contribute to clinical improvements when used in combination with rehabilitation programs (Mesci et al., 2009).

The purpose of this assessor-blinded, block randomized, controlled investigation, by Shu-Shyuan, Ming-Hsia, Yen-Ho, Ping-Keung, Jan-Wei, and Ching-Lin, was to study how acute stroke patients respond to different doses of neuromuscular electrical stimulation (NMES) on the upper-extremity.  Study participants were divided into three groups, the control group, the high dose NMES group with 60 minute sessions, and the low dose NMES group with 30 minute sessions.  After the regular inpatient rehabilitation, which all subjects received, the NMES groups received 4 weeks of NMES treatment.  Based on the subject's primary deficit, electrodes were placed over the extensor digitorum communis, extensor carpi radialis, flexor digitorum communis, supraspinatus, and/or the posterior deltoid.  Outcomes were measured by the upper-extremity motor section of the Fugl-Meyer Motor Assessment Scale, Action Research Arm Test, and Motor activity Log.  Results of the study showed a significant improvement for both the low dose and the high dose NMES when compared to the control group; however, there was not a significant difference between the two treatment groups.  

The article “Long-Term Effectiveness Of Neuromuscular Electrical Stimulation For Promoting Motor Recovery Of The Upper Extremity After Stroke,” found NMES beneficial for upper extremity motor recovery in stroke patients.  This study included 46 stroke survivors in a Chinese population who were split into a control group with standard rehab and an NMES intervention group also with standard rehab.  The intervention group received NMES, with electrodes placed over the supraspinatus, deltoid, and wrist extensors, 30 minutes a day, five days per week, for three weeks. The NMES frequency was set at 30 Hz with a pulse width of 300 us and a 1 second ramp time. A symmetrical biphasic waveform was used as stimulus pulse. The amplitude was increased as high as the patient could tolerate, up to 90 mA, to produce full wrist extension and 30-50 degrees of shoulder abduction. The duty cycle used was 5 seconds on/off. Measurements including the Modified Ashworth Scale for spasticity, the Fugl-Meyer motor assessment (upper extremity section), and the Modified Barthel Index were taken at weeks two and three during intervention and at one, three, and six months post intervention.  Results after three weeks of treatment and one month following the study found improvements in both groups.  Results after three and six months post intervention found significantly higher average scores in the NMES group than the control group. The authors concluded that NMES following stroke is beneficial for upper extremity motor recovery for at least six months following treatment.

Articles Refuting the Use of NMES

The article “Randomized Controlled Trial to Evaluate the Effect of Surface Neuromuscular Electrical Stimulation to the Shoulder After Acute Stroke,” found the effectiveness of sNMES inconclusive regarding the functional outcome of the shoulder after acute stroke.  This randomized control trial split 167 participants into two groups, a placebo group receiving only stroke unit care, and an intervention group receiving sNMES to the shoulder in addition to stroke unit care. The sNMES took place for one hour three times per day and the electrodes were placed over the supraspinatus and the posterior deltoid muscles. The frequency used was 30 Hz and the on/off time was 15 seconds with a 3 second ramp time. Intensity was increased until a muscle contraction was visible.  The placebo group appeared to receive the same treatment as those who received sNMES but the stimulator was internally disconnected so that no treatment took place.  The intervention lasted four weeks and was followed by primary measures of upper limb function using the Action Research Arm Test (ARAT) three months post stroke and secondary measures using the ARAT, Frenchay Arm Test, Motricity Index, Star Cancellation Test, pain scales, Nottingham E-ADL Index, Nottingham Health Profile, Oxford Handicap Scale, and participant views after the intervention and 3 months post stroke. The primary measure showed no difference between groups. Some secondary measures were improved in the placebo group 3 months post stroke, although there was no difference in ADL’s. The improvement in placebo over intervention was most prominent in those with initial severe impairment. The authors suggest this may be due to sNMES impeding the motor re-learning process and decreasing recovery in those with severe impairment. Immediately following intervention there was no difference between groups.  The authors suggest use of sNMES for people with initial severe impairment may have negative affects due to the following reasons: abnormal proximal afferent stimulation inhibiting plasticity and interfering with distal recovery, overuse of the arm from movement produced by sNMES, insensitivity and lack of awareness of stimulation, production of tiredness and shoulder subluxation, and sNMES promoting decreased use of affected arm. The authors would like those with upper limb deficits post stroke to be aware of the possible negative consequences associated with sNMES.

In the review done by Meilink, Hemmen, and Seelen et al., they looked at whether Electromyography-triggered neuromuscular electrical stimulation (EMG-NMES) that was applied to the extensor muscles of the forearm could improve hand function after a stroke (Meilink, Hemmen, Seelen, & Kwakkel, 2008).  The review was compiled via a computer-aided literature search and looked at comparing EMG-NMES of the upper extremity to usual rehabilitation protocol.  Eight studies were chosen out of 192 hits, and these 8 studies provided the review with 157 patients.  The meta-analysis of these reviews showed no significant effect sizes in favor of EMG-NMES for a number of tests including the Box and Block manipulation test, Action Reach ARM test and the Fugl-Meyer Motor Assessment Scale.  The abilities that were tested in the various reviews were reaction time, manual dexterity, sustained contractibility and upper extremity synergy.  The overall results of the review found that there was no statistical difference in the effects between EMG-NMES and the usual rehabilitation protocol.  It was found that most studies has poor methodical quality, low statistical power and insufficient treatment contrast between experimental and control groups (Meilink et al., 2008).

The researchers, Yavuzer, Geler-Külcü, Sonel-Tur, Kutlay, Ergin, and Stam, performed a randomized controlled trial to observe the effect of neuromuscular electric stimulation (NMES) on ankle dorsiflexion during the first 6 months after a stroke, when added to a conventional stroke rehabilitation program.  All participants received the conventional stroke rehabilitation program.  In addition, the NMES group received 10 minutes of NMES to the affected anterior tibialis muscle.  Outcome measures included lower-extremity motor recovery, assessed with the Brunnstrom stages for the lower extremity, and gait kinematics, assessing walking velocity, step length, percentage of stance phase at the paretic side, sagittal plane kinematics of the pelvis, hip, knee, and ankle, maximum ankle dorsiflexion angle at swing, and maximum ankle plantarflexion angle at initial contact.  Both groups demonstrated an improvement between the beginning and the end of the study, however, there was not a significant difference between the groups, indicating that NMES was not an additive benefit to the conventional stroke rehabilitation program, when assessing motor recovery and gait kinematics with patients after a stroke.   

References

Anon. Neuromuscular Electric Stimulation Effect on Lower-Extremity Motor Recovery and Gait Kinematics of Patients With Stroke: A Randomized Controlled Trial 10.1016/j.apmr.2005.12.041: Archives of Physical Medicine and Rehabilitation | ScienceDirect.com. Available at: http://www.sciencedirect.com.proxy.kumc.edu:2048/science/article/pii/S0003999306000487. Accessed February 24, 2012.

Church, C., Price, C., Pandyan, A. D., Huntley, S., Curless, R., & Rodgers, H. (2006). Randomized controlled trial to evaluate the effect of surface neuromuscular electrical stimulation to the shoulder after acute stroke. Stroke; a journal of cerebral circulation, 37(12), 2995-3001. doi:10.1161/01.STR.0000248969.78880.82

Gould, B. E., Dyer, R. M. (2011). Muskuloskeletal Disorders. Pathophysiology for the health professions. (4^th ed., pp. 587-588). Saunders.  

Hsu, S.-S., Hu, M.-H., Wang, Y.-H., Yip, P.-K., Chiu, J.-W., & Hsieh, C.-L. (2010). Dose-response relation between neuromuscular electrical stimulation and upper-extremity function in patients with stroke. Stroke; a journal of cerebral circulation, 41(4), 821-4. doi:10.1161/STROKEAHA.109.574160 

Lin, Z., & Yan, T. (2011). Long-term effectiveness of neuromuscular electrical stimulation for promoting motor recovery of the upper extremity after stroke. Journal of rehabilitation medicine : official journal of the UEMS European Board of Physical and Rehabilitation Medicine, 43(6), 506-10. doi:10.2340/16501977-0807

Meilink, a, Hemmen, B., Seelen, H. a M., & Kwakkel, G. (2008). Impact of EMG-triggered neuromuscular stimulation of the wrist and finger extensors of the paretic hand after stroke: a systematic review of the literature. Clinical rehabilitation, 22(4), 291-305. doi:10.1177/0269215507083368

Mesci, N., Ozdemir, F., Kabayel, D. D., & Tokuc, B. (2009). The effects of neuromuscular electrical stimulation on clinical improvement in hemiplegic lower extremity rehabilitation in chronic stroke: a single-blind, randomised, controlled trial. Disability and rehabilitation, 31(24), 2047-54. doi:10.3109/09638280902893626

Transcutaneous Electrical Nerve Stimulation

Transcutaneous electrical nerve stimulation (TENS) is a modality frequently seen within the physical therapy clinic, particularly in the outpatient setting. Clinically, it has been traditionally seen as a way to stimulate the sensory nerves (Prentice, 2011). The thought behind its pain relieving mechanism being that the mind will be subsequently tricked into paying attention to the electrical stimulus rather than the painful stimulus of the affected area (Prentice, 2011). The theory is deemed the gate control theory, and by way of maximally stimulating the sensory nerves, the painful afferent impulses being sent to the spinal cord level will be perceived as less or even not at all (Prentice, 2011).  TENS can also be modified to work via the descending mechanisms or endogenous opiate mechanisms of pain control (Prentice, 2011).

            Low back pain is a common ailment seen within the physical therapy clinic, and as such TENS is often used to treat the condition. Numerous studies have addressed the use of TENS for the treatment of low back pain. Both supporting and refuting evidence has come from these studies. First we will take a look at a few of the current research surrounding TENS as a successful modality in the treatment of low back pain.

            In a study by Melzack, Vetere and Finch, the researchers wanted to address the effectiveness of two common treatments for low back pain: transcutaneous electrical nerve stimulation versus gentle massage over the affected area. The thought behind comparing the two treatments being that both methods provide stimulation to the area, so one sensory input should prove greater than the other. This was a double-blind, randomized study design, in which 41 patients participated. The McGill Pain Questionnaire was used to assess pain levels both before and after treatment. Additionally, the researchers assessed return to function and the affect of the modalities via a straight leg raises and ROM in the low back (specifically flexion). It was found that TENS significantly reduced pain relative to gentle massage(Melzack, Vetere, & Finch, 1983).

Additionally, straight leg raises were improved but no increase in ROM was seen with either modality. This suggests that healing was not stimulated but perhaps the use of TENS to decrease pain allows patients to complete tasks they were previously capable of but unable to do due to pain. Within the group receiving TENS, 85% showed improved pain scores, while only 38% showed improved pain within the gentle massage group. The researchers conclude that TENS is a superior method to pain treatment for low back patients.  One problem seen within this study is that one may question the “massage” employed within the treatment. The researchers applied 4 suction cups that administered specific pressure changes to the area. One could see this as more of a placebo to TENS rather than massage. Either way, TENS would be deemed better than massage or a placebo with the outcomes aforementioned (Melzack et al., 1983).

Another study supports the use of TENS in patients with nonspecific chronic low pain back for controlling pain intensity. Chronic low back pain was described as a duration of greater than three months. One hundred fifty patients were included in a single-blind randomized control trial and divided into three groups (50-50-50) for each TENS, Interferential Current (IFC), and controls.  Significant reductions in pain intensity were found in both the TENS and IFC groups such that 84% of the TENS group and 75% of the IFC group were able to stop using NSAIDs and analgesic drugs after treatment sessions compared with 34% of the control group (Facci, Nowotny, Tormem, & Trevisani 2011). However, most patients in each group were not using any drugs, so more investigation could be performed to solidify these results.

What was more of interest regarding the treatment of pain for subjects was the implied cumulative effect of pain relief over the treatment sessions. Patients were given ten treatment sessions over two weeks. Using a visual analog scale (VAS), patients were evaluated for pain both before and after each treatment session.  In both the TENS and IFC groups, patients had significant reduction in mean pain intensity at the beginning and end of each session and from over the course of treatments. In the IFC group, subjects had the greatest duration of pain relief after session nine and in the TENS group after session ten. It would be worth investigating what the maximal pain relief duration could be for the TENS group beyond session ten, however, only ten sessions were given in this study. The findings here imply that patients should see immediate reductions in pain intensity after each session as well as a cumulative effect of pain relief with more sessions. It is unknown the optimal number of sessions for maximal pain relief while utilizing TENS in treating chronic low back pain (Facci et al., 2011).

A study by Cheing and Hui-Chan examined if a single sixty minute treatment of TENS could modify chronic (clinical) LBP, acute (experimental) pain, and the flexion reflex, an objective pain measurement tool, versus a placebo. Multiple studies can be found that either refute or confirm the thought that placebo treatment is just as effective in modifying pain as TENS and other modalities. This study sought to compare the pain modification in experimental versus placebo group in just one sixty minute session of TENS.  Thirty subjects between the ages of 18 and 50 with chronic low back pain for more than 6 months and experiencing pain daily were included in the trial. Two visual analog scales were use for the subject to report their pain: the VAS (LBP) was used to indentify intensity of LBP and the VAS (FR) was used to record the electrical pain during the FR recording. Also, the flexion response was recorded electromyographically after elicitation by an electrical stimulus to the sole of the foot.

The results showed a decrease in pain to 63.1% using the VAS (LBP) value in the chronic LBP group, and there was no difference in the placebo group. This decrease in pain also remained for the next hour. There were no differences seen between group in the VAS (FR) and flexion response after treatment. These differences were also not seen in the acute experimental pain group. Therefore the researchers conclude that a single sixty minute treatment is indeed beneficial for reducing pain in patients with chronic low back pain as compared to placebo. They believe that this reduction in pain is not seen in patients with acute pain because different nociceptive pathways are used in modifying chronic versus acute pain (Cheing & Hui-Chan, 1999). 

From the above studies, we see that in some instances, TENS can be beneficial for patients with low back pain.  However, there is also current evidence that suggests otherwise. We will now review the studies that did not support the use of TENS for chronic low back pain.  

An evidenced based review by Dubinsky and Miyasaki shows that TENS is ineffective overall in the treatment of chronic low back pain. Two Class I studies were analyzed. In one scenario, TENS was compared to a TENS-sham group, and no benefit was found for TENS using a visual analog scales.  The TENS-sham group was given an apparent “treatment”, however no electrical current was delivered (Dubinsky & Miyasaki, 2010). This particular study was looking for a 20% significant improvement in pain, but this threshold was not reached.  Twenty percent is a liberal definition of significance in pain relief; some studies require 25% or even 50% to be considered significant. The authors of this review did not identify the specific percentage of relief attained (if any) in this scenario.  In the second study, TENS and TENS-sham were administered for patients with multiple sclerosis and chronic low back pain. There were no significant differences in pain relief. Thus, the authors concluded from both Class I studies that TENS is not a good treatment choice for chronic low-back pain (Dubinsky & Miyasaki, 2010). The authors did not indicate how many subjects were included in each study; that would have been helpful to determine the reliability of these studies.

In a different study by Chou and Huffman, researchers again wanted to explore the common modalities used within the physical therapy practice to treat low back pain. The researchers began by identifying common treatments including exercise, massage, diathermy, superficial head, transcutaneous electrical nerve stimulation and more. The authors then performed a review of literature surrounding the topic and included studies through 2006 (Melzack, Vetere & Finch’s study previously discussed in our article was included in this study).  They chose to only include randomized trials, which included outcomes for the treatment of low back pain. In summary, the study found that cognitive-behavioral therapy, exercise and spinal manipulation were moderately effective in chronic low back pain. In contrast, acute low back pain was only found to significantly improve via superficial heat and possibly spinal manipulation. Overall, through the review of 16 clinical trials specifically addressing low back pain and TENS, there is insufficient evidence to suggest TENS is superior to “sham TENS” or any other intervention. The systematic review also suggests that minor skin irritation occurs in 1/3 of patients receiving TENS (Chou & Huffman, 2007).

A study by Deyo et al, sought to determine if TENS was more effective than a general stretching and exercise program with sham TENS, and if the addition of TENS to an exercise program adds any benefit. One hundred forty- five patients were randomly assigned to 1 of 4 groups: TENs alone, TENS plus exercise, sham TENs alone, or sham TENS with exercise. The patients were assessed at follow ups on functional performance, pain (using VAS scales as well as self- rating intensity and frequency), and physical performance. The results found no additive benefit of TENS.  At a one month follow up there was no significant effect of TENS on functional performance, pain, or physical performance, and there was no additional effect seen when adding TENS to exercise. Also, there was no significant difference between the TENS and sham TENS treatments. The most significant result is that at the one month follow up, the exercise alone group showed decreased VAS scores, frequency of pain, and improved functional performance. However, it is important to note that at the two month follow up, if the subject in the exercise group had stopped doing their exercises, the before seen improvement were no longer there. Thus it is important to stress to patients that they need to continue their exercises if they want continued improvements in pain reduction (Deyo et al., 1990).

In analyzing the evidence both in support of and refuting the use of TENS for chronic low back pain; it is our opinion that TENS may have some pain relieving benefits for a certain patient group. The decrease in pain seems to be immediate, but not long too long in duration.  None of the studies reviewed claimed that the pain was nonexistent, but rather that the pain was decreased.  Whether you choose to use TENS or an alternative analgesic modality, we believe it is important to refer to current evidence and utilize best judgment for each patient situation.  

References

 
Cheing, G. & Hui-Chan, C. (1998). Transcutaneous electrical nerve stimulation: nonparallel           antinociceptive effects on chronic clinical pain and acute experimental pain. Archives of               Physical Medicine and Rehabilitation, 80(3), 305-312.

Chou, R., & Huffman, L. H. (2007). Nonpharmacologic Therapies for Acute and Chronic Low Back Pain: A Review of the Evidence for an American Pain Society/American College of Physicians Clinical Practice Guideline. Ann Intern Med, 147(7), 492-504. Retrieved from http://www.annals.org/cgi/content/abstract/147/7/492.

Deyo, R., Walsh, NE, Martin, DC, Schoenfeld, LS, & Ramamurthy, S. (1990). A Controlled Trial of Transcutaneous Electrical Nerve Stimulation (TENS) and Exercise for Chronic Low Back Pain. The New England Journal Of Medicine, 322: 1627–34.

Dubinsky, Richard M. & Miyasaki, Janis. (2010). Assessment: Efficacy of transcutaneous electric nerve stimulation in the treatment of pain in neurologic disorders (an evidence-based review): Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology 2010; 74;173.  doi: 10.1212/WNL.0b013e3181c918fc.

Facci, Ligia M., Nowotny, Jean P., Tormem, Fabio, & Trevisani, Virginia F.M. (2011). Effects of transcutaneous electrical nerve stimulation (TENS) and interferential currents (IFC) in patients with nonspecific chronic low back pain: randomized clinical trial. Sao Paulo Med Journal 129(4), 206-16.

Melzack, R., Vetere, P., & Finch, L. (1983). Transcutaneous electrical nerve stimulation for low back pain. A comparison of TENS and massage for pain and range of motion. Physical therapy, 63(4), 489-93. American Physical Therapy Association. Retrieved from http://ptjournal.apta.org/content/63/4/489.abstract

Prentice, William E. (2011). Therapeutic Modalities in Rehabilitation. (4^th ed.). China: McGraw-Hill Companies, Inc.  

Manual Lymphatic Drainage

The clinical syndrome that we chose was lymphedema following breast cancer.  Breast cancer is the most common cancer in women and will typically affect one out of eight women over the course of their lifetime (Breast Cancer, 2010). If the breast cancer is diagnosed and treatment is started quickly there is a very positive prognosis for these patients.  However, there are side effects of the treatment and one of the side effects is lymphedema.   One technique that a physical therapist can use is called manual lymphedema drainage.  This is a technique that has shown positive effects when combined with other modalities.  The technique involves using your hands to pump the arm and push the lymph into uninvolved lymph nodes. The purpose of this blog entry is to review six articles, three pro manual lymph drainage and three against it.   

Articles Supporting MLD

The first article we found was taken from the British Medical Journal and was published January 2010 issue (Torres Lacomba et al., 2010).  This study was a randomized, single blinded, clinical trial. Their objective was to study the effects that early physical therapy would have on women, who had surgical treatment for breast cancer, and the likelihood of secondary lymphedema developing. According to the authors, seventy one percent of women develop secondary lymphedema after surgery for breast cancer, which could be attributed to multiple factors.  The factors include lymph node removal, obesity, wound infection, lack of range of motion, and drainage.  The study involved patients at a hospital over at three-year span.   Women were included if they had unilateral surgery and axillary lymph node dissection.  The patients were randomly assigned into two groups, a control group and an intervention group.  The interventions group received manual lymph drainage from an experienced physiotherapist, performed exercises for the muscle group affected by the surgery, and were educated on the lymphatic system.  The control group received the same educational information that the interventions group received, but they did not have the other two interventions.  The statistical comparisons were binary outcome analysis to view the likelihood of lymphedema developing and continuous outcome analysis to view how the circumference changed, as well as the difference in arm circumference of two adjacent locations. 

The first article found that physiotherapy, manual lymph drainage, and patient education had a significant effect.  The interventions group developed secondary lymphedema in seven percent, while twenty-five percent of the control group developed lymphedema.  The authors stated that oedemas are caused by an imbalance of filtration and reabsorption.  The theory of the manual lymph drainage is that it helps to move lymph out of the affected tissue and improves the reabsorption.  The author’s of the study hypothesized that the manual lymph drainage post surgery had the possibility to increase positive outcomes.  According to the authors’ their limitations included the time frame of their follow up and that they chose one criteria for diagnosing lymphedema.  However, the authors’ believed that their intervention had a positive effect on the women who have unilateral surgery with axillary node dissection.  They believed their intervention helped to prevent secondary lymphedema, which in turn improves the quality of patient life. 

The second article analyzed 138 women of whom 55% had a combination of four types of treatments: manual lymph drainage (addressed in our video), compression, arm exercises, and deep breathing (also addressed in our video). 32% of the women received manual lymph drainage alone and 13% had very mild lymphedema which was treated by the patient themselves with instructions from a therapist.

The results showed that there was a 55.7% improvement in the women that had all four therapies concurrently and 41.2% improvement in the women that had manual lymph drainage alone.  Due to the embarrassing, and possibly debilitating, nature of a severely swollen limb due to lymphedema, this article provides important evidence in support of the manual lymphatic drainage intervention.

The final article supporting MLD consisted of two groups: the first group received MLD followed by simple lymphatic drainage (SLD), and SLD followed by MLD.  Thirty-one subjects that had unilateral lymphedema of greater than 10% for at least 3 months one year after breast cancer treatment participated in this study. The first group received 3 weeks of MLD (15 treatments), followed by 6 weeks of nothing, and then 3 weeks of SLD.  The second group had 3 weeks of SLD, followed by 6 weeks of nothing, and then 3 weeks of MLD (15 treatments).  This study showed that MLD in the early phases of lymphedema produced a statistically significant reduction in excess limb edema (9.65%), compared to SLD, which had a non-significant reduction in limb volume (3.85%).

Articles Refuting MLD

The first article that was against manual lymph drainage (MLD) was a randomized, single blind, control study (Devoogdt et al., 2011).  This study objective was to view how patients with breast cancer and axillary node dissection would respond to an intervention of MLD, exercise, and education.  The patients were selected over at two and half year time period based on their surgery and lymph node dissection.  From this they narrowed their patients down to one hundred sixty patients who agreed.  The patients were randomly selected for the interventions or control group.  The difference between the two groups was that the interventions group would receive MLD for 20 weeks beginning with the first week after the drainage tube was removed.  The MLD treatment began with the neck and axillary nodes, followed by the back and breast tissue, and finally the arm and hand.  This was done using a proximal to distal drainage technique.  Four different therapists performed this method of MLD, these for therapists also instructed the patients through exercise and education.

            The primary results of this study were that patients in the interventions group had almost the same likelihood of developing lymphedema after surgery.  According to the study, twenty four percent of patients in the interventions group developed lymphedema, as opposed to only nineteen percent in the control group.  The secondary outcomes were that each group had similar changes in arm volume.  According to the authors, after the six months of treatment the interventions group had no statistically significant changes.  This led the authors to conclude that MLD does not affect the prevention of lymphedema over a short time period.  This study did provide limitations and strengths.  The limitations of the study were half of the therapists performing the treatments were inexperienced (trained before the study) while the other half had more experience.  The strengths of the study were pre and post surgery measurements, stratification of patients, and randomized grouping. 

            The second article that was against MLD was a prospective, randomized control study that compared the use of MLD with compression versus only compression (McNeely et al., 2004).  The purpose was to look at how effective the combination of MLD and compression would be at decreasing volume of lymphedema. The patients were females with unilateral breast cancer and axillary node dissection.  As another exclusionary criteria the patients were required to be diagnosed with lymphedema.  The patients were randomly placed into either the control group (receiving only compression bandage) or the intervention group (compression and MLD).  The patients in each group received 4 weeks of treatment.  For the group receiving MLD the Vodder method was used.  The compression bandaging was layered and short stretch bandages were applied in a figure eight pattern. 

            The primary outcome of this study was that there was not a significant difference between the control group and the intervention group.  This was determined by the difference in the unaffected arm compared to the affected arm.  The authors’ point out that their study is in agreement with previous studies regarding compression and MLD.  However, the authors’ do mention that the patients who had mild lymphedema had better results from the MLD and the compression.  The authors’ hypothesize that because they have mild lymphedema there is still a functioning lymphatic system, which allows the lymph to be moved effectively.  They also hypothesize that the compression affects the filtration rate from artery to tissue and because the pressure is changed there is an increase in venous return.  Based on these two ideas they believe that compression is more effective in severe lymphedema due to lymphatic system damage.  The limitations for this study included the time period, upper extremity range of motion was not measured, and they did not assess pain, function, or quality of life. 

            The final article aimed to find out if MLD, added to standard therapy, improved the outcome for patients with stage 1 or 2 lymphedema after breast cancer treatment. Andersen et al. said that the most important reduction of edema happens in the first two weeks.  Forty-two patients at least 4 months post breast cancer treatment who had one or more symptoms of unilateral lymphedema, a difference in limb volume of at least 200 ml, and/or a difference of circumference of at least 2 cm participated in this study.  They were randomly assigned to receive standard therapy or standard therapy plus MLD.  Standard therapy included a custom made compression sleeve, education, and exercises.  The experimental group received standard therapy plus MLD 8 times in 2 weeks and was instructed on simple lymphatic drainage for home.  The results concluded that both groups had significant reduction in lymphedema, especially in the first month, and then continued to slightly decline in the next 11 months.  The standard therapy group saw a 60% reduction of edema after 3 months, compared to 48% in the MLD group.  Both groups reported a significant reduction of limb volume, discomfort, and an increase in joint mobility.

            Collectively, these articles suggest that compression, especially in the early stages of lymphedema, is the most important aspect of treatment. However, including MLD in treatment may help clear edema in some patients.  Because MLD is a massage technique there also could be psychological benefits for the patients that were not quantified in any of the studies we viewed.  In conclusion, the articles were somewhat inconclusive, but showed that MLD does have positive benefits when combined with other treatments.  

References 

Andersen, L., Højris, I., Erlandsen, M., & Andersen, J. (2000). Treatment of breast-cancer-related lymphedema with or without manual lymphatic drainage--a randomized study. Acta oncologica (Stockholm, Sweden), 39(3), 399-405. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/20218087 

Breast Cancer." PubMed - Health. 28 Dec. 2010. Web. 03 Feb. 2012. <http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001911/>.

Devoogdt, N., Christiaens, M.-R., Geraerts, I., Truijen, S., Smeets, a., Leunen, K., Neven, P., et al. (2011). Effect of manual lymph drainage in addition to guidelines and exercise therapy on arm lymphoedema related to breast cancer: randomised controlled trial. Bmj, 343(sep01 1), d5326-d5326. doi:10.1136/bmj.d5326

McNeely, M. L., Magee, D. J., Lees, A. W., Bagnall, K. M., Haykowsky, M., & Hanson, J. (2004). The addition of manual lymph drainage to compression therapy for breast cancer related lymphedema: a randomized controlled trial. Breast cancer research and treatment, 86(2), 95-106. doi:10.1023/B:BREA.0000032978.67677.9f

Rashmi Koul, M.D., Tarek Dufan, M.D., Catherine Russell, B.P.T., Wanda Guenther, R.M.T.,Zoan Nugent, Ph.D., Xuyan Sun, M.Sc., Andrew L. Cooke, F.R.C.P.C. "Efficacy of complete decongestive therapy and manual lymphatic drainage on treatment-related lymphedema in breast cancer." International Journal of Radiation Oncology*Biology*Physics (2007): 841-846.

Torres Lacomba, M., Yuste Sanchez, M. J., Zapico Goni, A., Prieto Merino, D., Mayoral del Moral, O., Cerezo Tellez, E., & Minayo Mogollon, E. (2010). Effectiveness of early physiotherapy to prevent lymphoedema after surgery for breast cancer: randomised, single blinded, clinical trial. BMJ, 340(jan12 1), b5396-b5396. doi:10.1136/bmj.b5396

Williams, a F., Vadgama, a, Franks, P. J., & Mortimer, P. S. (2002). A randomized controlled crossover study of manual lymphatic drainage therapy in women with breast cancer-related lymphoedema. European journal of cancer care, 11(4), 254-61. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/12492462