A. The usual incision for exposure of the lower three slips of the
serratus is shown. The patient can be operated on in the supine, half-lateral,
or full-lateral position. The ideal position is half-lateral because this
provides good access to the axilla and the angle of the scapula. The incision
usually begins over the eighth rib and sweeps up in a C shape into the
axilla, paralleling the posterior axillary fold.
B. The incision has been made and the anterior border of the latissimus
muscle has been identified. The slips of the serratus can be seen passing
deep to the latissimus. Inferiorly, the serratus and latissimus adhere
densely to one another and must be separated with sharp dissection. Superiorly,
the cleavage plane between the two muscles is easily developed.
C. As the latissimus is elevated, the subscapular vessels or the thoracodorsal
vessel as it reaches the undersurface of the latissimus can be visualized.
The branch to the serratus is usually visualized first and can be traced
proximally to its junction with the thoracodorsal or subscapular artery.
The long thoracic nerve is anterior to the vessels under the chest wall
fascia and does not usually come into view until the vascular structures
are well mobilized.