Pain relieving modalities are the most commonly used in physical therapy. When a patient experiences pain they have difficulty participating in their rehabilitation regimen. One of the main goals in pain management in physical therapy is to have a modality that is non-invasive and efficient. Transcutaneous electrical nerve stimulation units (TENS) are an effective pain management device that can be used in a multitude of patient populations.
How Does Transcutaneous electrical nerve stimulation (TENS) Work?
When using a TENS unit, two pads are placed over or near the injured area of the body. The unit emits an electrical signal when activated. This electrical pulse stimulates the release of the body’s own natural opioid pain-relieving chemicals.
Part of effectively using a TENS unit for relieving muscle pain involves understanding where to place the electrodes. Generally speaking, TENS electrodes should be placed around the perimeter of the area to be treated in order to be effective. This allows the current to travel through the nerve fibers within the affected muscles. However, it should be noted that if the area is inaccessible for some reason, for example migraine pain that is felt in the head and face, TENS can still be used effectively. In this case, the electrodes would be placed on a corresponding area, say the shoulders, and the signals to block or “scramble” pain sensations are still sent to the brain thus decreasing the migraine pain.
What Pain Problems Can TENS Help Alleviate?
TENS is useful for a multitude of patient problems and can help alleviate pain for the following issues:
Soft Tissue Injuries
- Cervical radiculopathy
- Bursitis or Hip Pain
- Carpal Tunnel
- Plantar Fasciitis
- Lateral epicondylitis or Tennis Elbow
- Frozen Shoulder
- Multiple Sclerosis
- Temporomandibular joint disorder or dysfunction (TMD)
TENS can also be combined with other modalities for greater pain relieving effectiveness and efficiency. For example, TENS is often combined with ultrasound and several combination devices are offered on the market because the two modalities work together so well.
Combination Therapy Units are great because treatment minutes are precious. It’s imperative to have tools that can work together toward patient goals. Additionally, storage space is usually at a premium in clinics. Ultrasound and TENS combination units save both time and space by providing these versatile modalities in one machine. A study , Effectiveness of Ultrasound Combine TENS in Treatment of Upper Trapezius Myofascial Pain (MPS), published in the U.S. National Institutes of Health found that combination units were more effective in treating myofascial pain in the upper trapezius.
How to Place Electrodes When Using a TENS Unit
While a good rule of thumb is to place electrodes near the injured or painful area, we find it’s useful to have diagrams to show proper placement. Having illustrated diagrams for electrode placement is also useful for patients who purchase home units and want to use their TENS unit on their own.
The below illustrations are provided by Current Solutions. They show recommended electrode placement for the common areas of the body where pain is treated with TENS therapy. The electrode placement diagrams shown here display electrodes for a 2-Channel Venti TENS unit, which uses 4 total electrodes – 2 electrodes per channel.
When a patient is using a unit at home, it’s important for them to follow the recommendations of this TENS Unit Electrode Placement Guide, but also follow the directions of their healthcare practitioner.
|Example TENs Electrode Placements|
Some other protocols that should be adhered to when using a TENS unit are:
- 1.Skin must be clean and dry.
- 2.Put a thin coat of gel on the bottom of each electrode. This gel helps the electrical signal get to the nerves under the skin.
- 3.The electrodes should be pressed firmly against the skin (adhesive can be used to keep them in place).
- 4.Hook the pin connectors on the end of the electrode wires to the electrodes. Then plug the electrode wires into the TENS unit.
- 5.When starting treatment, adjust slowly to find the correct setting. Patient will feel a slight tingling feeling.
- 6.Set timer to adhere to specific timing protocols for each patient’s diagnosis.
- 7.Always, refer to the user manual for the specific TENS unit’s other precautions.
When treating in physical therapy, modalities are utilized to help decrease pain and increase function. With the diverse treatment applications of a TENS unit, it’s a perfect addition to many rehabilitation regimens. And with its ability to be used by the patient at home, TENS units are a great non-invasive pain management alternative to oral medication.