Page 1102 - Adams and Stashak's Lameness in Horses, 7th Edition

1068 Chapter 10

VetBooks.ir 90°

115° ICLD ICLD
or
DDFT

DDFT

Figure 10.44. Treatment guidelines for foals with flexural
deformities of the DIP joint based on the angle of the dorsal hoof
wall relative to the ground. Source: Reprinted with permission from
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Adams and Santschi. Reproduced with permission of American
Association of Equine Practitioners.
angles of 90° or less and in most foals with deformities
between 90° and 115° (Figure 10.44). An inferior check
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ligament desmotomy is highly recommended in foals and
those older than 1 year of age that have not responded to
conservative therapy, with hoof deformities approaching
or beyond vertical, with osteolysis of the distal phalanx,
Figure 10.43. Elevation of the heel vs. the toe with a wedge in and that cannot touch the heel to the ground.
horses with flexural deformities of the fetlock can help guide both The surgery can be performed with the traditional
surgical and conservative treatment. In most horses, heel elevation open approach in the proximal metacarpus or with ultra­
causes the fetlock to drop and improves the angle of the fetlock. sound guidance through a 1‐ to 2‐cm incision. 15,23,24,29,33
Trimming the heel and using a shoe with a toe extension,
toe elevation, or rocker shoe is recommended following
desmotomy have an improved prognosis for normal surgery in most cases (especially older horses) to achieve
hoof conformation and for athletic performance. 29,35 a normal hoof conformation as quickly as possible.
Surgical options for horses with deformities of the Normal limb alignment may be obtained almost immedi­
MCP joint include an inferior check ligament desmot­ ately following surgery, but relaxation may progress for
omy, a superior check ligament desmotomy, both inferior 7–10 days postoperatively. Normal hoof conformation
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and superior check ligament desmotomies, and SDFT should be achieved within 2 weeks of surgery in most
tenotomy in the mid‐metacarpus. 1,2,17,32 There is scarce cases. Several studies have documented that the majority
information regarding the prognosis of horses with MCP of foals treated with an inferior check ligament desmot­
flexural deformities following surgery. However, in the omy develop a normal hoof conformation and can be
authors’ experience, lack of response to surgery and used for their intended purpose. 24,29,33,35 Experimental
recurrence of the flexural deformity is much more studies also have documented that transection of the
common with MCP joint deformities than with DIP joint inferior check ligament causes minimal changes in loco­
deformities. In addition, multiple surgeries may be motion, joint angles, or strains to the palmar soft tissue
required since the source of the deformity is harder to structures in normal horses. The surgery itself should
6,7
initially identify. There should be at least 2 weeks between have minimal effects on future performance.
surgeries, since some horses will improve more a few Tenotomy of the DDFT is usually reserved for older
days after surgery than they did immediately post‐op. horses (older than 1 year) with severe deformities of the
The majority of DIP deformities can be corrected with DIP joint. A DDFT tenotomy is recommended if the
an inferior check ligament desmotomy. This includes all hoof‐ground angle is more than 115° (Figure 10.44).
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type I and many type II deformities if the surgery is per­ Foals with deformities between 90° and 115° may
formed at a young age (younger than 6–8 months) and if respond to an inferior check ligament desmotomy, and
combined with corrective shoeing such as a toe extension this should be attempted initially. However, the response
and/or toe elevation. 23,35 An inferior check ligament des­ to surgery is less predictable in these cases. 2,23 The DDFT
motomy is recommended in foals with hoof‐ground tenotomy may be performed in the mid‐metacarpus or