[Muscle-sparing latissimus dorsi flap. Vascular anatomy and indications in breast reconstruction]

The muscle-sparing latissimus dorsi flap pedicled on descending branch presents distinct advantages in breast reconstruction, specially when there is a transversely oriented skin paddle, including reduced donor site morbidity, sparing muscle function and greater freedom of orientation of the skin paddle. This study reports the anatomical basis, surgical technique, advantages and complications of this technique. Four clinical cases illustrate surgical indications in breast reconstructive surgery.

An anatomical cadaveric study underwent to University of Texas Southwestern Medical Center, Dallas. The goal was performed to determine the location of the bifurcation of the thoracodorsal artery and the course of its descending branch compare to the anterior side of latissimus dorsi muscle. Four clinical cases illustrated indications of muscle-sparing latissimus dorsi flap pedicled on descending branch in breast reconstruction. These cases showed advantages and complications of the technique, and impact on donor site.

Fifteen descending branch muscle-sparing latissimus dorsi flaps were harvested. All flaps had a bifurcation of the thoracodorsal artery. The average was located at 5,1cm from posterior axillary side (from 2,1 to 7,5 cm) and average of 2,2 cm from the anterior side of latissimus dorsi muscle (from 1,3 to 3,1cm). To 5, 10 and 15 cm from posterior axillary side, the descending branch was located at respectively an average of 2,0 cm (from 1,4 to 2,5), 2,4 cm (from 1,3 to 3,3), and 2,9 cm (from 2,0 to 3,8) behind the anterior side of latissimus dorsi muscle. The average length of descending branch was measured at 15,2 cm (from 13,2 to 19,0). None clinical cases paddle suffering was observed. Donor site morbidity was less than classical or extended adipomuscular technique. Latissimus dorsi muscle function is spared.

The muscle-sparing latissimus dorsi flap, pedicled on descending branch, is versatile and reproducible. It results in minimal functional deficit of the donor site, absence of seroma, large freedom of orientation of the skin paddle, low rate of flap complications, and a cosmetically acceptable scar. There are a lot of indications in breast reconstruction.