2. The angle of the scapula is noted. The superior transverse border of the latissimus dorsi crosses at just about this level toward the vertebral column.

3. The midline of the back as palpated over the vertebral spines is marked from T-6 inferiorly to the sacrum.

4. The outline of the posterior superior iliac crest is marked; this represents the caudal insertion of the latissimus dorsi.

5. The remainder of the anterior border of the latissimus dorsi muscle must be estimated although this is not a palpable structure because the muscle proceeds inferiorly. Its position may be estimated by a continuation of the palpable border of the latissimus in the posterior axillary fold that is extended inferiorly and somewhat obliquely in a posterior-inferior direction to the posterior superior iliac crest.

6. The position of the dominant vascular pedicle to the latissimus from the subscapular-thoracodorsal axis is estimated at the apex of the axilla, entering the proximal portion of the latissimus muscle beneath its anterior border in the posterior axillary fold. The thoracodorsal nerve runs with the vascular pedicle in a posterior and deeper plane.

7. During the dissection, the serratus anterior muscle and its vascular pedicle are identified. The vascular supply to the lower portion of the serratus anterior is through a dominant branch from the subscapular-thoracodorsal vessels into the latissimus dorsi. To obtain the longest vascular leash to supply the latissimus transplant, this vascular pedicle to the serratus anterior has to be divided, unless the lower three slips are to be carried with the latissimus.

8. The serratus anterior muscle is identified during the dissection, extending from the angles of the scapula to the ribs anteriorly. The serratus is intimately associated with the anterior border of the latissimus dorsi muscle from the middle third of the chest down to the ninth rib. With their blood supply arising from the subscapular-thoracodorsal system, the lower three slips of the serratus muscle may be carried with the latissimus, increasing the potential size of the transplant by about 25%.

9. The trapezius muscle will be identified in its relationship to the superoposterior portion of the latissimus dorsi as it approaches the vertebrae. The entire trapezius muscle, like the serratus, will be preserved when the latissimus dorsi is harvested.

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