Effect of low level laser therapy (830 nm) with different therapy regimes on the process of tissue repair in partial lesion calcaneous tendon.
OBJECTIVE
Calcaneous tendon is one of the most damaged tendons, and its healing may last from weeks to months to be completed. In the search after speeding tendon repair, low intensity laser therapy has shown favorable effect. To assess the effect of low intensity laser therapy on the process of tissue repair in calcaneous tendon after undergoing a partial lesion.


METHODS
Experimentally controlled randomized single blind study. Sixty male rats were used randomly and were assigned to five groups containing 12 animals each one; 42 out of 60 underwent lesion caused by dropping a 186 g weight over their Achilles tendon from a 20 cm height. In Group 1 (standard control), animals did not suffer the lesion nor underwent laser therapy; in Group 2 (control), animals suffered the lesion but did not undergo laser therapy; in Groups 3, 4, and 5, animals suffered lesion and underwent laser therapy for 3, 5, and 7 days, respectively. Animals which suffered lesion were sacrificed on the 8th day after the lesion and assessed by polarization microscopy to analyze the degree of collagen fibers organization.


RESULTS
Both experimental and standard control Groups presented significant values when compared with the control Groups, and there was no significant difference when Groups 1 and 4 were compared; the same occurred between Groups 3 and 5.


CONCLUSIONS
Low intensity laser therapy was effective in the improvement of collagen fibers organization of the calcaneous tendon after undergoing a partial lesion.
Department of Plastic Surgery, São Paulo Federal University-UNIFESP, São Paulo, SP 04024-900, Brazil.
Flávia Schlittler
FS
Oliveira
Carlos Eduardo
CE
Pinfildi
Nivaldo Antônio
NA
Parizoto
Richard Eloin
RE
Liebano
Paulo Sergio
PS
Bossini
Elvio Bueno
EB
Garcia
Lydia Masako
LM
Ferreira
D000125:Achilles Tendon / Q000293:injuries* / Q000473:pathology / Q000528:radiation effects; D000818:Animals; D003094:Collagen / Q000528:radiation effects / Q000648:ultrastructure; D028022:Low-Level Light Therapy; D008297:Male; D026741:Physical Therapy Modalities; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014945:Wound Healing; D014949:Wounds, Nonpenetrating / Q000532:radiotherapy* / Q000534:rehabilitation*
D003094:Collagen