Page 154 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

Chapter 11 · Thoracic wall anatomy and surgical approaches

Latissimus dorsi muscle flap: Pedicled muscle flaps are
ideal for reconstruction of chest wall defects because of
VetBooks.ir dorsi muscle is the most common autogenous flap used
their large size and good survival rates. The latissimus
for reconstruction of chest wall defects in both dogs and
humans (Liptak et al., 2008a) because of its location rela-
tive to the chest wall, large size, good arc of rotation to
permit coverage of the majority of chest wall defects and
excellent flap survival based on the thoracodorsal artery
and extensive anastomoses between its intercostal and
thoracodorsal pedicles. The latissimus dorsi flap can be
harvested either as a muscle alone or as a myocutaneous
flap (Halfacree et al., 2007); it is a type V muscle flap
based on the thoracodorsal artery arising at the level of
the caudal depression of the shoulder (Purinton et al.,
1992). The dorsal border of the flap extends from ventral
to the acromion and the caudal border of the triceps
muscle to the head of the 13th rib. The ventral border is
A typical chest wall defect following resection of a caudal rib
11.13 osteosarcoma. Note the exposure of the abdominal cavity. In either the ventral border of the muscle, if intact, or the
such cases, the thoracic cavity can be reconstructed by advancing the incised edge if part of the latissimus dorsi is excised en
diaphragm and then the abdominal wall is reconstructed with bloc with the rib tumour (Figure 11.15a). Perforating inter-
autogenous and/or prosthetic techni ues. diaphragm I intestines costal vessels are ligated and divided, allowing elevation
Li liver Lu lungs spleen. of the flap and rotation into the chest wall defect (Figure
11.15b). The muscle flap is sutured to the cranial and
In dogs, the selection of a chest wall reconstructive caudal ribs of the chest wall defect and the ventral pec-
technique depends on the size and location of the defect. toral musculature with an interrupted or continuous
Surgical techniques to reconstruct chest wall defects in suture pattern using monofilament absorbable suture
dogs include: autogenous latissimus dorsi muscle and material (Figure 11.15c). Chest wall defects of up to six
myocutaneous flaps; deep pectoral muscle flap; external ribs have been reconstructed with latissimus dorsi
abdominal oblique muscle flap; omental pedicle flap; dia- muscle flaps in dogs. For larger defects, the latissimus
phragmatic advancement; using prosthetic mesh; a dorsi muscle flap can be used to reconstruct part of the
mesh–methylmethacrylate sandwich; and rib replace- defect and a prosthetic mesh used for the remainder of
ment with rib grafts or spinal plates. the defect (see Figure 11.14bc).

(a) (b)
(a) A large chest wall defect and cutaneous defect following the
11.14 resection of six ribs for a primary rib chondrosarcoma, including
en bloc excision of an adhered lung lobe (see Figure 11.11) and pericardium.
The cutaneous defect was larger than normal because of combined excision
of both the biopsy tract and a concurrent grade II mast cell tumour with 3 cm
lateral margins. The cutaneous defect was closed primarily. Note the partial
sternectomy to achieve adequate ventral margins. (b) A latissimus dorsi
muscle flap L can be used to reconstruct chest all defects resulting from
the resection of up to si ribs but occasionally this muscle flap ill not be
su cient to reconstruct the chest all defect if part of the muscle has been
excised en bloc with the tumour, if the chest wall defect is not within the arc
of rotation of the muscle flap or if the chest all defect is too large such as
with this chest wall defect resulting from the excision of a primary rib
chondrosarcoma with six ribs and a portion of the latissimus dorsi muscle.
c If the latissimus dorsi muscle flap L is not su cient for reconstruction
(c) of the entire chest wall defect, then autogenous reconstruction can be
supplemented with a prosthetic mesh (PM).

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