PAIN SCORES AND SIDE EFFECTS IN RESPONSE TO LOW LEVEL LASER THERAPY
(LLLT) FOR MYOFASCIAL TRIGGER POINTS
E Liisa Laakso Carolyn Richardson, and Tess Cramond
1: Physiotherapy Department, Royal Brisbane Hospital, Brisbane;
2: Physiotherapy Department, University of Queensland, Brisbane;
3: Pain Clinic, Royal Brisbane Hospital, Brisbane, Queensland, Australia.
Clinically, Low Level Laser Therapy - LLLT has been used successfully
in the treatment of chronic pain but many have questioned the scientific
basis for its use. Many studies have been poorly designed or poorly
controlled. A double-blind, placebo-controlled, random allocation
study was designed to analyze the effect of second daily infrared
(JR) laser (820 nm, 25mW) and visible red laser (670 nm, 10 mW) at
1 J/cm2 and 5 J/cm2 on chronic pain. Forty-one consenting subjects
with chronic pain conditions exhibiting myofascial trigger points
in the neck and upper trunk region underwent five treatment sessions
over a two-week period. To assess the progress, pain scores were measured
using visual analogue scales before and after each treatment. The
incidence of side effects was recorded. All groups demonstrated significant
reductions in pain over the duration of the study with those groups
which received infrared (820nm) laser a 1 J/cm2 and 5 J/cm2 demonstrating
the most significant effects (p< 0.001). Only those subjects who
had active laser treatment experienced side effects. Results indicated
that responses to LLLT at the parameters used in this study are subject
to placebo and may be dependent on power output, dose and/or wavelength.
Key words: chronic pain, Visual Analogue Scal, LLLT, side effects,
phototherapy.
Addressee for Correspondance:
E Liisa Laakso BPhty PhD,
Physiotherapy Department Royal Brisbane Hospital
Herston Queensland
Australia 4029
6/97 Rep. US $8-10-12 copyright 1997 by LT Publishers, U.K. Ltd.
Manuscript received: January, 1997 Accepted for publication: March,
1997
LASER THERAPY.9: 67-72 67
Two wavelengths studied.
Best results with the higher-powered infrared laser compared with
the lower powered red laser.
| Wave- Length |
Average Power |
Energy Density |
Power Density |
Energy |
Pulses |
Time |
Beam Spot Size |
| 820 |
25mW |
5 J/Cm2 |
0.89 W/Cm2 |
0.14 J |
5,000 Hz |
5.62 secs |
.089Cm2 |
|
