Ultrasounic thetapeutic effect on metacarpal &ac:ture heaIDg in equine (HistomorphoIog study)

Abstract

Astudy was undertaken to evaluate histomorphologically the effect
of ultrasound therapy after creating " wedge fracture " on the left
metacarpal bone in 12 clinically healthy adults donkeys between 4
to 6 years age and 150 to 300 Kg/Bw. These animals were
randomly divided in two groups of I, II of 6 animals each. These
groups were further divided into two subgroups of la, lIa of one
month and Ib, lib of two months duration of 3 animals each.
Ultrasound therapeutic regimen of 1 MHz with intensity of 1
W/Cm2 for 10 minutes for 10 days was started a week after
fracture creation in animals group II where as group I acted as
control one. The macroscopic and microscopic study of callus was
done at the end of one and two months observation period. The
samples collected were decalcified and were stained with H&E
stains. There was the adhesions between surrounding soft tissue
and callus were rough, hard and strong. The adhesions were more
irregular and extensive in the la animals than lIa ones. The callus
appeared sufficiently elevatedfrom the adjacent periosteal tissue
and was soft and light grey colour. It was gritty during trephining
on 30 days after fracture creation. The scar tissue and adhesions
were present as a small and distinct layer of fibrous mass between
skin, muscles and the fractured bone. The callus had a bony colour
and it was well demarcated from periosteal surface with a rough,
uneven and raised remnant of periosteal collar in the Ib animals,
where as only few foci of adhesions were present between the site
of fracture and surrounding tissues. The callus surface was more
smooth and it had regained its original bony colour in lIb animals
on 60 days gross observation. H&E staining revealed that the
hematoma had almost completely been replaced with dense fibrous
tissue and numerous cartiflagenous cells at different stages of
chondrification had been observed in Ia animals where as fracture
was densely filled with fibrinous and cartilagenous tissue and the
newly formed osseous trabeculae were observed in lIa animals too.
The entire fracture gap was almost ossified with mixture of
cartilagenous and bony tissue in Ib animal. But in lib animals
ossification was more advanced and union of fracture site with
ossified callus was evident.