Continuous Validity of Pedicled Myocutaneous and Myofascial ... - NCI

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Continuous Validity of Pedicled Myocutaneous & Myofascial Flaps
In our study (PMMC) flap was used in 84
cases with a very high success rate (98.8%),
whether this success was primary without any
complications (79.8%) or secondary to successful
management of minor complications that
delayed healing (19%). Major flap loss requiring
salvage reconstruction by latissimus dorsi flap
occurred in only one case. Different series had
reported varying incidences of complications,
63% [18], 58% [19], 36.1% [2]. Fewer complications
were reported when using the myofascial
flap only [18,20]. The incidence of major or total
flap loss was varying from 0% [21], to 1.5% [4],
to 2.4% [2,18].
The main indications in our study were oral
and partial pharyngeal defects.
In an old series done in the Egyptian NCI
in 1985 [4], pedicled (PMMC) flap was used
for pharyngoplasty after total laryngopharyngectomy
in 50 patients and in another series
done in 1986 [10], latissinus dorsi myocutaneous
flap was used for the same purpose in 28 cases.
In our study, pedicled (PMMC) flap was used
in only one case for reconstruction after this
kind of surgery in a patient with poor general
condition that could not withstand neither free
jejunal flap nor gastric pull up.
Pedicled myocutaneous flaps are rarely used
nowadays to reconstruct the pharynx after total
laryngopharyngectomy as this method has many
disadvantages that includes development of
fistula and stenosis and due to the evolution of
gastric pull up and free jejunal flaps and their
established use in such cases.
Gastric transposition is more commonly
used after pharyngolaryngo-oesophagectomy
in our institute, owing to increased multidisciplinary
experience in this form of surgery and
in relation to the advanced pathological stage
of hypopharyngeal carcinoma at presentation
in which total esophagectomy is needed to
obtain proper lower safety margin [22].
In our study the (PMMC) flap was used to
reconstruct the anterior wall of the pharynx
after total laryngectomy in 12 cases receiving
prior radiotherapy (In 2 cases the mucosa was
closed primarily & the muscle flap was used as
a buttress to augment the suture line and replace
the skin defect, and in 10 cases the skin island
was used to repair the mucosal defect). In the
latter group, intentional pharyngostomy was
done after resection in 7 cases, and 3 cases
developed major fistulae after trial of primary
closure. In these 10 cases, the skin island of the
(PMMC) flap was used to reconstruct the mucosal
defect and the skin defect was reconstructed
by deltopectoral fasciocutaneous flaps. The
latissimus flap was used for this purpose in only
one case in a female with large breast.
Iginio Tansini in 1896 [23] was the first
surgeon who performed the pedicled latissimus
myocutaneous flap. He used it in reconstructing
skin defects after surgery of breast cancer.
However, this procedure was put to rest when
Halsted started his radical mastectomy using
thin skin flaps instead of removing wider skin
area. Olivari in 1976 [24] rediscovered this flap
and since then it gained its popularity in reconstruction
of major defects that occurred after
radical surgery for malignancies in the breast,
chest wall and head & neck areas.
Its blood supply is based on the thoraco
dorsal vessels that run 8-14cm before entering
the muscle just above the mid point of its free
border. Its cranial vascularity allows it to have
wide arc of rotation that it can cover any defect
from the sternum anteriorly to the midline posteriorly
and it can reach to the upper border of
the ear [10].
When the donor site is less than 10x12 cm,
it can be closed primarily but wider defects will
need skin grafts. The largest reported size of
this flap was 35x20 cm [25]. Olivari 1979 [26]
proved the presence of 27 perforating arteries
going between the muscle and the overlying
skin.
One of the greatest advantages of the latissimus
dorsi flap over other regional myocutaneous
flaps as the pectoralis major flap is that
one can control the thickness of the muscle due
to the anatomical fact that the main arterial
supply runs along the lateral thin border of the
muscle and gives its branches to the bulk of the
muscle medially [10].
Elevation of the skin island overlying the
latissimus dorsi muscle and dissecting the dominant
perforating vessel, permit independent
positioning of the skin island in relation to the
muscle (razor flap) thus decreasing the donor
site morbidity [27].