Page 163 - Manual of Equine Field Surgery

Modified Forssell's Operation for Cribbing
Figure 26-5 Once tl1e spinal accessory
nerve is identified, it can be bluntly dissected
free from the muscle to expose a 5- to 10-cm
section of the nerve to be removed.
POSTOPERATIVE CARE
«: . '!:t• c
os
P t qgera,., 1ve are
Exercise Restridions: The horse should be
confined to a stall for 2 weeks with controlled
handwalking only.
Medications: Phenylbutazone is administered at
4.4 mg/kg BID for the initial 24 hours and 2.2
mg/kg BID for an additional 2 days. Broad-spec-
trum antibiotic therapy is indicated until 24 hours
after drain removal.
Suture Removal: Sutures are removed 12 to 14
days after surgery.
Stent Removal: The stent is typically removed
2 days after surgery.
Drain Removal: The Penrose drain is removed
2 to 5 days after surgery depending on the
amount of drainage. · various levels of cribbing following st1rgery. For-
Other: In the event that hematomas or seromas
occur, they should be managed conservatively.
COMPLICATIONS
The most common complication is failure to
resolve the behavioral abnormality.i" Factors that
may help to minimize recurrence of the cribbing
behavior include excising the muscle belly cranial
enough to preve11t scar tissue from facilitating
retraction of the larynx and instituting environ-
mental and behavioral changes. Other complica-
tions include seroma or hematoma formation and
incisional infections. Seromas and hematomas are
best treated by controlling bleeding at the time of
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159
Sternomandibularis m.
Rostral . Caudal
Ventral branch
of
accessory n.
Sternohyoideus m.
surgery, .applying adequate counterpressure to the
wound postsurgery, and limiting exercise in the
immediate postoperative period. The long-term
consequences of the incisional complications are
minimal. These incisions can heal very well by
second intention if necessary, Therefore, even
with complete dehiscence, the incisions heal with
very little scar formation. A cosmetic defect may
be present at the site of muscle resection, partic-
ularly if the muscles are resected in the mid-
cervical region.
EXPECTED OUTCOME
Reported success rates using the modified Fors-
sell's procedure range from SOo/o to 100%.1-3'6
Many horses undergoing this procedure show
tunately, most just apply their teeth to a flat object,
such as the top of a post or fence, but do not grasp
as they did prior to surgery and do not flex the
neck or make gulping noises as they did prior to
surgery. Success has been attributed to transecting
the sternohyoideus and ornohyoideus rostral to
the ventral aspect of the larynx. This success may
occur because the entire insertion of the omohy-
oideus is removed. If a more caudal transection is
performed, it is difficult to include all of the omo-
hyoideus. Additionally, remaining rostral portions
of the sternohyoideus muscle may establish some
adherence to the surrounding tissues and regain
some retraction function. Cosmesis is generally
very good, particularly if the muscle transections
are as far proximal and distal as recommended.
Muscle resections in the mid cervical region may
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