In physical therapy treatment, the use of transcutaneous electrical nerve stimulation (TENS) is used to reduce muscle spasm, improve tightened soft tissue, and alleviate pain. The TENS is used in conjunction with stretching to aid in relaxation and decrease pain Karasuno et al. (2016). In an injured muscle, a muscular guarding occurs. Muscular guarding is hyperactivity in the muscle spindle and decreases the threshold of the muscle spindle. Also, a state of ischemia in the muscle occurs when the muscle is constantly contracted. The inflammatory mediators and excitation of nociceptor are the algesic substances that are produced in an injured muscle. In an injured muscle, muscle and tendon shortening occurs that causes the pain with range of motion Karasuno et al. (2016).
In the study by Karasuno et al. (2016), 15 young men, ages 18-26 years old. The researcher had 2 subject groups. One group only performed stretches, while the other group used the TENS and then proceed with the stretches. The research resulted in decreased muscle hardness, increase in straight leg raises and decreased muscle hardness with TENS use along with stretching rather than stretching alone (Karasuno et al. (2016).
A suggestion for clinicians is to add TENS unit in the list for muscular pain management if appropriate for the patient. TENS is a nonpharmacological and a least invasive treatment to help decrease pain.
Reference
Hiroshi Karasuno, Hisayoshi Ogihara, Katsuyuki Morishita, Yuka Yokoi, Takayuki Fujiwara, Yoshiro Ogoma, & Koji Abe. (2016). The combined effects of transcutaneous electrical nerve stimulation (TENS) and stretching on muscle hardness and pressure pain threshold. Journal of Physical Therapy Science, 28(4), 1124–1130. Retrieved from http://ezproxy.csusm.edu/login?url=https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=115299032&site=ehost-live