Page 162 - Manual of Equine Field Surgery

158 HEAD AND NECK SURGERIES

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Incision site

for modified
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Forssell's

procedure

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Figure 26-3 The sternomandibularis muscle is

retracted laterally exposing the insertion of the ventral

branch of the spinal accessory nerve. In most cases, a

small amount of fascia covers the nerve and will need

to be dissected off to expose the nerve,

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Fi gu re 26-1 Incision site for modified Forssell's pro-

cedure. A 30-cm ventral midline incision starts 2 cm

rostral to the larynx at the basihyoid bone and extends

caudally.

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Figure 26-2 Lateral view of neck illustrating the Figure 26-4 The insertion of the spinal accessory

approximate insertion site of the ventral branch of the nerve is best identified by palpation for a depression on

spinal accessory nerve as it traverses the axial surface of the axial border of the sternomandibularis muscles.

the sternornandibularis muscles (dotted lines) prior to

entering the muscle belly approximately 5 cm caudal to

the musculotendinous junction.

myectomy and a sternothyroideus tenectomy

nomandibularis muscle to expose the nerve. are then performed as described i11 Chapter 25.

Contraction of the sternomandibularis muscle Additionally, when performing myectomy for

and flexion of the head are observed when the cribbing behavior, a portion of the omohyoideus

nerve is pinched with hemostats. A 5- to 10-cm is removed and the sternohyoideus and omohy-

section of nerve is exposed using blunt dissection oideus are ideally transected rostral to the ventral

and removed (Figure 26-5). A sternohyoideus aspect of the larynx.