Immediate pain relief effect of low level laser therapy for sports injuries: Randomized, double-blind placebo clinical trial

doi:10.1016/j.jsams.2016.03.006

Journal of Science and Medicine in Sport

Volume 19, Issue 12, December 2016, Pages 980-983

https://doi.org/10.1016/j.jsams.2016.03.006 Get rights and content

Abstract

Objectives

To determine the immediate pain relief effect of low-level laser therapy on sports injuries in athletes and degree of pain relief by the therapy.

Design

Double-blind, randomized, comparative clinical study.

Methods

Participants were 32 college athletes with motion pain at a defined site. Participants were randomized into two groups in which the tested or placebo laser therapy was administered to determine pain intensity from painful action before and after laser irradiation, using the Modified Numerical Rating Scale. The post-therapeutic Modified Numerical Rating Scale score was subtracted from the pre-therapeutic Modified Numerical Rating Scale score to determine pain intensity difference, and the rate of pain intensity difference to pre-therapeutic Modified Numerical Rating Scale was calculated as pain relief rate.

Results

Low-level laser therapy was effective in 75% of the laser group, whereas it was not effective in the placebo group, indicating a significant difference in favor of the laser group (p < 0.001). Pain relief rate was significantly higher in the laser group than in the placebo group (36.94% vs. 8.20%, respectively, p < 0.001), with the difference in pain relief rate being 28.74%.

Conclusions

Low-level laser therapy provided an immediate pain relief effect, reducing pain by 28.74%. It was effective for pain relief in 75% of participants.

Introduction

Sports injuries constitute a serious problem for many athletes and others who participate in sports because they cause pain and dysfunction, resulting in the inability to continue sports activities. Various physical therapies, including electrotherapy, thermotherapy, cryotherapy, and phototherapy, have been used to alleviate symptoms of sports injuries such as pain.1, 2, 3 Low-level laser therapy (LLLT) has been clinically introduced as one of such physical therapies.

LLLT has been examined in clinical research and reported to be effective for its long-term effect on many diseases in the general adult population.4, 5, 6 Bjordal et al.⁷ reported that a single session of LLLT relieved tenderness at the affected site in patients with Achilles tendinitis, and they demonstrated both immediate and long-term effects on injuries in the general adult population.

Studies on the effect of LLLT on sports injuries in athletes are limited to the reports of its effect on sprained ankles⁸ and Achilles tendinopathy.⁹ In both of these studies, the effect of LLLT was the same as was observed in the general adult population. In the study by Stergioulas⁸ in patients with sprained ankles, LLLT that was given twice daily significantly alleviated edema at 24–72 h as compared with placebo therapy. In another study by Stergioulas et al.⁹ in recreational athletes with Achilles tendinopathy, the combination of eccentric exercise and LLLT for 4–12 weeks alleviated motion pain as compared with placebo therapy. Thus, LLLT has been demonstrated to alleviate edema and pain associated with sports injuries in a few days to weeks. However, these studies did not provide any data on the immediate pain relief effect of LLLT on sports injuries in athletes.

Because athletes with sports injuries need earlier functional recovery compared to members of the general population, the immediate effect of LLLT is important. Therefore, this study was designed to evaluate whether LLLT provides an immediate pain relief effect on sports injuries in athletes and to determine the extent of pain relief by LLLT.

Section snippets

Materials and methods

A double-blind, randomized, placebo-controlled, parallel-group comparison study was performed. Participants were randomly assigned to the laser or placebo group.

Forty-seven college athletes met the following inclusion criteria: participation in intercollege to athletic activities 5 days/week or more; treatment at Osaka University of Health and Sport Sciences Clinic between July 1, 2013, and January 31, 2015 for sports injury; and diagnosis by an orthopedist with an orthopedic sports injury for

Results

Their characteristics and comparison are shown in Table 2. No significant difference in injury sites (p = 0.556, Table 2) or number of days after injury (p = 0.706, t = 0.380, Table 2) was observed between the groups. The rate of participants in whom LLLT was effective was 75% in the laser group and 0% in the placebo group, and the rate of participants in whom LLLT was ineffective was 25% in the laser group and 100% in the placebo group, with a significant difference between the groups (p < 0.001, χ² =

Discussion

Although an earlier study⁹ showed that long-term LLLT had a pain relief effect on Achilles tendinopathy in sports injuries, no studies have specifically examined the immediate pain relief effect and PRR of LLLT in injured athletes who need early return to play. Therefore, to examine the immediate pain relief effect of LLLT on sports injuries, this study was performed as a double-blind, randomized, placebo-controlled clinical trial to compare the pain relief effect of one session of LLLT in the

Conclusions

To examine the immediate pain relief effect of LLLT on sports injuries, the present study was performed as a randomized, double-blind, placebo-controlled, clinical study comparing the pain relief effect of a single session of LLLT with that of placebo laser therapy. The results revealed that LLLT relieved pain associated with sports injuries by 36.94%. Based on the difference from the placebo therapy, the rate of pain relief from low-level laser irradiation was 28.74%, and significant immediate

Practical implications

•
Low-level laser therapy has immediate effect of pain relief for motion pain in sports injuries.
•
Low-level laser therapy should be applied to a small treatment area for pain relief.
•
Low-level laser therapy should not apply to the patients with inability to define the painful area and absence of definite motion pain.

Acknowledgements

The authors received no assistance, including research grants, except for the placebo laser device lent from Minato Medical Science Co., Ltd. The authors thank the athletes who participated as subjects in this study.

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Original researchImmediate pain relief effect of low level laser therapy for sports injuries: Randomized, double-blind placebo clinical trial

Abstract

Objectives

Design

Methods

Results

Conclusions

Introduction

Section snippets

Materials and methods

Results

Discussion

Conclusions

Practical implications

Acknowledgements

Lancet

Neurosci Lett

Brain Res Bull

Treatment of spondylolysis with external electrical stimulation in young athletes: a critical literature review

Br J Sports Med

Treatment of acute ankle ligament injuries: a systematic review

Arch Orthop Trauma Surg

Management of acute lateral ankle ligament injury in the athlete

Knee Surg Sports Traumatol Arthrosc

A systematic review with procedural assessments and meta-analysis of low level laser therapy in lateral elbow tendinopathy (tennis elbow)

BMC Musculoskelet Disord

A meta-analysis of clinical effects of low-level laser therapy on temporomandibular joint pain

J Phys Ther Sci

A randomised, placebo controlled trial of low level laser therapy for activated Achilles tendinitis with microdialysis measurement of peritendinous prostaglandin E2 concentrations

Br J Sports Med

Low-level laser treatment can reduce edema in second degree ankle sprains

J Clin Laser Med Surg

Original research
Immediate pain relief effect of low level laser therapy for sports injuries: Randomized, double-blind placebo clinical trial