Low-level laser therapy improves early healing of medial collateral ligament injuries in rats.
OBJECTIVE
This study sought to investigate whether or not low-level laser therapy (LLLT) with a helium-neon laser increased biomechanical parameters of transected medial collateral ligament (MCL) in rats.


BACKGROUND
It has been reported that LLLT can enhance tendon healing.


METHODS
Thirty rats received surgical transection to their right MCL, and five were assigned as the control group. After surgery, the rats were divided into three groups: group 1 (n = 10) received LLLT with 0.01 J/cm(2) energy density per day, group 2 (n = 10) received LLLT with 1.2 J/cm(2) energy density per day, and group 3 (sham = exposed group; n = 10) received daily placebo laser with shut-down laser equipment, while the control group received neither surgery nor LLLT. Biomechanical tests were performed at 12 and 21 days after surgery. The data were analyzed by one-way analysis of variance.


RESULTS
The ultimate tensile strength (UTS) of group 2 on day 12 was significantly higher than that of groups 1 and 3. Furthermore, the UTS and energy absorption of the control (uninjured) group were significantly higher than those of the other groups.


CONCLUSIONS
LLLT with a helium-neon laser is effective for the early improvement of the ultimate tensile strength of medial collateral ligament injuries.
Bayat
Mohammad
M
Cell and Molecular Biology Research Center, Medical School, Shaheed Beheshti University of Medical Sciences, Tehran, Iran. bayat_m@cyahoo.com
Delbari
Ali
A
Almaseyeh
Mohammad Ali
MA
Sadeghi
Yousef
Y
Bayat
Maryam
M
Reziae
Fatemesadat
F
D000818:Animals; D004307:Dose-Response Relationship, Radiation; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D017888:Medial Collateral Ligament, Knee / Q000293:injuries*; D051381:Rats; D017208:Rats, Wistar; D013718:Tensile Strength; D014945:Wound Healing