Page 327 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

302 CHAPTER 1

VetBooks.ir 1.576

Fig. 1.576 Lateral and medial branches
of the SDFT (split screen showing
palmarolateral and palmaromedial
transverse scans). The lateral branch (lb)
is markedly enlarged compared with the
medial branch (mb). The deep digital flexor
tendon is displaced medially. sdsl = straight
distal sesamoidean ligament.

1.577

Fig. 1.577 Transverse ultrasonogram
of the SDFT in the proximal digital
(pastern) area. The left image shows
an enlarged lateral SDFT branch. It
contains a well-defined hypoechogenic
lesion (arrow), although the remainder of
this branch also appears heterogeneous.
The right image shows the normal
medial branch (arrowhead). The
latter is smaller but is surrounded by
hypoechogenic material representing
inflamed synovial tissue.

a superficial SDFT tear. Complete rupture of both echogenicity to that of normal parenchyma and
branches (Fig. 1.578), or avulsion of their insertions because the lesion often enlarges over several days
on the palmar processes of P2, are rare occurrences (Figs. 1.580, 1.581). Examination is best carried
and both lead to subluxation of the proximal inter- out around 10–15 days after injury to confirm the
phalangeal joint (Fig. 1.579). diagnosis and determine the localisation, size, extent
The initial ultrasonographic examination may be and severity of the lesion. The latter is assessed based
performed during the first week after injury, but the on increased CSA of the tendon, decrease of echo-
owner should be warned that it might underestimate genicity, CSA of the lesion (relative to that of the
the severity and extent of the damage at that stage, tendon), loss of fibre alignment and proximodistal
both because early haematoma may have a similar length of the lesion.