IJCRR

IJCRR - 4(9), May, 2012

Pages: 11-17

Date of Publication: 17-May-2012

EFFICACY OF TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION (TENS) IN TREATMENT OF NEUROPATHIC PAIN IN PATIENTS WITH DIABETIC NEUROPATHY

Author: Anjan Desai, Khushbu Desai

Category: Healthcare

Abstract:Introduction: Diabetic Neuropathy is a peripheral nerve disorder caused by diabetes that leads to pain in periphery. Many patients are limited in their physical activity by pain. The study conducted to assess the effect of Transcutaneous Electrical Nerve Stimulation (TENS) application for reduction of pain in patients with diabetic neuropathy. Aim of study: The main objective of this study is to compare the effectof TENS on Diabetic Neuropathy patients in reduction of pain and improving single limb stance. Materials and Methodology: Study Design: An experimental comparative study. Sample Selection: A sample of 30 patients diagnosed as diabetic neuropathy were taken from after giving due consideration to inclusion and exclusion criteria. Sample size: Total 30 including Control Group (Group A): The patients in this group were given therapeutic exercise training only and Experimental Group (Group B): The patients in this group were given treatment with TENS application and therapeutic exercise training. Inclusive Criteria: Patients of diabetic neuropathy affecting unilateral lower limb defined as ? 50% loss of strength and sensation of foot relative to non-affected side and complain of pain duration ? 5 months. Exclusion Criteria: Patients with age group between the 50-60 years and Patients with other pathological conditions of foot i.e. gout, spondylolysthesis, gangrene and spinal disease. Outcome measures: Visual analogue scale and Single limb stance. Results: The subject's parameters calculated by using Paired t test for within group comparison and unpaired t test used for between group comparisons. The mean and standard deviation of the measurement were also calculated. The training induced changes were significantly greater in the experimental group than the control group in Visual analogue scale and Single limb stance. Conclusion: It concluded that the treatment with TENS has good effect on Diabetic Neuropathy patients in reduction of pain and improving single limb stance.

Keywords: Diabetic Neuropathy, Transcutaneous electrical nerve stimulation (TENS)

Full Text:

INTRODUCTION
Diabetes mellitus is clinical syndrome characterized by hyperglycemia due to absolute or relative deficiency of insulin (1); the incidence of diabetes among age increased 90% from 4.8 per 1,000 in 1995-1997 to 9.1 in 2005-2007(2) . Lack of insulin causes the various metabolic imbalances leading to irreversible functional & structural changes in cell body with these of vascular and nervous system being affected the most, among people suffering from diabetes mellitus, 45% of patient will have neuropathy during the course of disease(3) . Diabetic neuropathy is a peripheral nerve disorder cause by diabetes, is characterized by gradual loss of sensations i.e. touch , temperature, vibration with loss of coordination and balance leading to weakness and wasting of muscles of hands and feet(4) . Diabetes changes the way nerve use glucose leading to accumulation of sorbitol & depletion of substance called myoinositol within the nerves.(5) Excessive blood sugar decreases the level of nitric oxide present in the blood leading to constriction of small vessels supplying a nerves contributing to nerve damage. The damaged nerve fiber sends incorrect signals to other pain centers giving rise to Neuropathic pain (6) . The main objective of the treatment is to decrease pain & improve single limb stance with simplify possible regimen. Medical management concentrates on oral hypoglycemic drugs aided by use of non–steroidal anti-inflammatory drug along with exercise and dietary changes. Transcutaneous Electrical Nerve Stimulation (TENS) is a specific therapeutic approach to control the Neuropathic pain in patients with diabetic neuropathy (7). TENS either activates the gate control mechanism or induces the release of endogenous opiate substances to relieve pain (11) . Neurological Rehabilitation programme aim at reducing pain, improve single limb stance, functional mobility, activities of daily living, quality of life and perhaps survival in patients with diabetic neuropathy. Many patients with diabetic neuropathy are limited in their physical activity by pain (12). Subjects undergoing treatment with TENS may be beneficial effect in diabetic neuropathy patient to reduce severity of pain and improving the single limb stance (13) . The study conducted to determine whether the TENS has effective on Diabetic Neuropathic pain.

MATERIALS AND METHODOLOGY
Study Design:
An experimental comparative study.

Materials: Control Group (Group A): Tuning fork, Inch tape, Digital stopwatch, goniometer and TENS.

Sample size:
A total number of 30 patients diagnosed as diabetic neuropathy selected and divided in two groups. The study carried out as before and after study design with control group.

Control Group (Group A):
The patients in this group had given treatment with therapeutic exercise to reduce pain.

Experimental Group (Group B):
The patients in this group had given treatment with TENS application and therapeutic exercise to reduce pain.

Study setting:
The study was conducted on patients diagnosed as diabetic neuropathy, which were referred for physiotherapy management from neurology ward of South Central Railway Hospital, Secunderabad and experiment was conducted at Sri Sai Physiotherapy Clinic, Kothapet, Andhra Pradesh, India.

Duration:
Treatment given for 20 minutes/sessions, 2 sessions /day for 5 days in a week for the both groups for 1 month.

Subject selection criteria:
Inclusion Criteria:
- Diabetic neuropathy affecting unilateral lower limb defined as ≥ 50% loss of strength and sensation of foot relative to non-affected side.
- Complain of pain duration ≥ 5 months.

Exclusion Criteria:
- Age group was between 50-60 years.
- Pathological conditions of foot: gout, spondylolysthesis, gangrene and spinal disease.

Parameters:
Visual Analogue Scale: Visual analogue scale is a most valuable and highly subjective measure mental scale that tries to measure a characteristic or attitude that has to range across a continuum of values. Visual analogue scale used for determine the intensity of pain. The amount of pain that patient feels ranges across a continuum from none to an extreme amount of pain. Operationally a Visual analogue scale is usually horizontal line, 10 cm. in length, encored by word descriptors at each and patient‘s marks on the line that the point that they feel represents their perception of current state. The left side of the line represents no pain. Moreover, the right side represents the worst pain. Visual analogue scale is consistent reliable and easy to use and took less time to administer. Visual analogue scale used before and after to measure effectiveness of treatment and a patient‘s progress. Visual analogue scale is a valid and reliable measure of chronic and acute pain intensity.

Single Limb Stance:
Single limb stance is an objective type of gait variable in which one extremity is in contact with the ground or supporting surface. Foot placed pointing straight forward in relation to reference line in the frontal and sagittal planes. The other leg was flexed 90 degree at hip and knee with both arm hang at side. Patients were instructed to stand as motion less as possible, look straight ahead at the point on wall 65cm. away. Patients informed to be in position until the time they can, with normal time about 60 seconds.

Procedure
Technique of application: Every session started with 5 minutes assessment of sensation, range of motion and muscle strength. In prone lying position, TENS given with high frequency rectangular pulse shape, Pulse width between 200 to 400 µsec, Pulse rate between 60 to 100 Hz, Intensity between 44 to 60 mA and single channel surface electrode was used.

Group A: Subjects in the control group given only therapeutic exercise program. The total exercises training time was 20 minutes daily for 5 to 6 days in a week with total duration of 4 weeks.

Group B: Subjects in experimental group given treatment with Transcutaneous electrical nerve stimulation along with exercise programme for pain reduction. The total training time was 20 minutes daily for 5 to 6 days in a week with total duration of 4 weeks.

RESULTS
Paired t test used for within group comparison and unpaired t test used for between group comparisons. Within group comparison

The Visual Analogue Scale and Single Limb Stance have shown a mean improvement indicating the effect of treatment in Group B patients who had beneficial effects. Exercise only did not show an improvement in a short duration of 4 weeks. The mean improvement in the patient‘s condition measured using visual analogue scale and single limb stance indicating the reduction of pain achieved by treatment in this study. Visual analogue scale had a significant improvement. The ?t? value indicates the significant change in experimental group than the control group. DISCUSSION The study measurements assessed for preexercise and post-exercise sessions of both Group A and Group B. The post exercise parameters assessed by paired ?t? test and the formulated ?t? values were compared with the table values with a degree of freedom 14. The study demonstrated that in diabetic neuropathy patients, treatment with the TENS reduces pain and improves single limb stance. The study conducted with great care to ensure familiarization with the treatment and the length of the training session as prescribed in clinical trials. Diabetic neuropathy contributes to pain and reducing single limb stance (4). The measurement recorded after the treatment period in both the groups has variations. The experimental group, who treated with TENS, had significant variations indicating the reduction of pain and improvement in single limb stance. There have been earlier studies that reported significant reduction in pain by treatment with TENS. (9) The study showed that TENS administration was followed by reduction, but not abolition of pain in lower extremity at all painful sites. Finally, the reduction in pain intensity reported here is typical of that observed in patients with diabetic neuropathy who were treated with TENS (7) . The earlier studies for reduction of pain in diabetic neuropathy had shown that TENS could relive the pain by altering nociceptive

transmission in the dorsal horn of the spinal cord (15). The other mechanism requires that stimulation delivered to the spinal cord segments that innervate the painful area via ventral rami of spinal nerves(17), however also innervate the skin of lower back via dorsal rami. Thus, TENS delivered to the dorsal columns reduced the Neuropathic pain in patients with diabetic neuropathy. CONCLUSION The level of significance of visual analogue scale and single limb stance had shown change after the treatment with TENS and had proved reduction of pain in diabetic neuropathy patients. The calculated ?t? value greater than tabulated ?t? value in parameters, standing that the results are highly significant and so the hypothesis goes in favor of the Experimental hypothesis with the reduction in pain and improvement in single limb stance. Thus the study concluded by rejecting null hypothesis and accepting the experimental hypothesis. The experimental hypothesis of the study states, ?There is a significant reduction in pain and also improvement in single limb stance by treatment with Transcutaneous electrical nerve stimulation application in patients with Diabetic Neuropathy.? ACKNOWLEDGMENTS Authors are sincerely grateful to the god who showered his blessings and his helping hand for our research. Sincerely Authors are thankful to our principal who helped us in every walk of our research and his support. The knowledge he shared and his encouragement helped us a lot. Authors would like to mention special thanks to my entire faculty who were always a standing rock for our great work. Authors are privilege to thank our respected elderly subjects without whom this research was not been possible. Authors heartily thankful to authors, journals and books from where references for this article has been reviewed and discussed.

Conflict of Interest: None

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