The surgeon makes the incision while standing posterior to the patient, with the first assistant on the other side of the table across from the surgeon. The incision begins midway between the medial border of the scapula and the spine, proceeding downward parallel to these two structures for the first few inches and then curving in a gentle S one fingerbreadth below the tip of the scapula, and finally extending down into or just below the submammary crease, if necessary. In exposures of the fourth or fifth interspace, the medial end of the incision is extended transversely toward the sternum. For lower openings of the seventh or eighth interspace, or ones involving transection of the costal cartilages for maximum exposure, the medial end of this incision curves gently toward or into the epigastrium. The surgeon then carries the incision directly down through the latissimus dorsi and the serratus anterior muscles (figure 2). During this process, each of the muscles may be elevated individually by the surgeon’s index and middle fingers. This is accomplished by entering the auscultatory triangle formed by the superior border of the latissimus dorsi, the inferior border of the trapezius, and the medial border of the scapula.
The incision is extended anteriorly and posteriorly through the borders of the trapezius and rhomboid muscles. Care must be taken to make this posterior incision parallel to the spinal column and thus lessen the chance of dividing the spinal accessory nerve, which innervates the trapezius. Bleeders are cauterized as they appear. By palpating the widened interspace between the first and second ribs and the insertion of the posterior scalene muscle on the first rib, the surgeon may count down to the appropriate rib level (figure 3). The pleural space should be entered just over the superior part of the rib to eliminate the potential for injury to the neurovascular bundle (figure 4). The periosteum is incised directly over the midportion of the rib (figure 4). The sacrospinalis muscle and fascia are elevated by a periosteal elevator, and a retractor is inserted in this space. A Coryllos periosteal elevator is swept anteriorly along the upper half of the rib (figure 5). The Hedblom periosteal elevator is then inserted under the bared portion of the rib and slipped upward along the rib, stripping the remaining periosteum from the upper half of the rib in a posterior-to-anterior direction (figure 6). After ensuring that the patient is on single lung ventilation (i.e., no ventilation to the side being operated upon), a small incision is made entering the pleura (figure 7). The lung drops away, thus allowing the incision to be extended for the desired length. A cross section of this approach is shown beneath figure 5.
An alternative method is direct incision into the intercostal space. The incision is made through the intercostal muscles along the superior border of the rib. Simple ligation of these is sufficient. Dissection is carried directly down and into the pleura. The incision in the pleura is extended anteriorly and posteriorly with cautery. The internal mammary vessels, which join the intercostals at the sternum, lie medial and deep to the costal cartilages and should not be injured during this incision (figure 8). If additional exposure is required, a rib may be divided or resected. The periosteum along the lower border of the rib is stripped to isolate the neurovascular bundle, which is grasped between right-angled forceps, ligated, and divided. The rib is then transected at the costal cartilage of the neck with rib shears (figure 9). A self-retaining retractor is inserted (figure 10) and opened gradually.