Plasma rico em plaquetas no tratamento de tendinite induzida em eqüinos: avaliação ultra-sonográfica

The objective of the study was to evaluate the effect of platelet-rich plasma (PRP) in the treatment of induced tendinitis in the superficial digital flexor tendon (SDFT) of horses through ultrasonographic evaluation. Thus, six 8 to15-year-old healthy gelding horses (x=12 years) were used. Tendinitis of the SDFT was provoked in both forelimbs via intratendineous administration of 2.5mg of collagenase (2.5mg.mL-1), what was considered as beginning of the experimental phase. Twelve days after induced tendinitis, the horses were submitted to two treatments: (1) in the lesion caused in the right SDFT (treated group, TG), 2.5mL of PRP activated with calcium chloride at 0.0125mol.L-1, at concentrations from 320,000 to 500,000 platelets.µL-1, were administered; (2) in the tendinitis of the left SDFT (control group, CG), 2.5mL of 0.9% saline solution was administered. After 5 days, the animals were submitted to controlled and progressive physical activity during 30 days. Ultrasonographic examinations were carried out before and after tendinitis induction (48 hours after and on experimental days 7, 12, 14, 21 28, 35 and 42), with tendon cross-sectional area (CSA), lesion cross-sectional area (L-CSA), L-CSA percentage, severity and echogenicity of the lesion, as well as collagen fiber alignment being evaluated. The result revealed reduction (P<0.05) in the L-CSA and in the degree of lesion echogenicity in function of time, but with difference (P<0.05) between groups only for L-CSA, with smaller values in TG. The treatment with PRP promotes greater reduction in the area of the lesion measured by ultrasound.