Oblique lateral incision and subpectoral dissection in modified Nuss procedure minimize future breast deformity

Background We experienced the occurrence of breast deformity in some young female patients who underwent a modified Nuss procedure before breast development. We studied the causes of and preventive measures for this complication. Methods We classified 13 prepubescent female patients who underwent our modified Nuss procedure into three groups according to the direction of the skin incision and the dissection layer for bar insertion. Four patients who underwent transverse lateral thoracic skin incision and bar insertion through a subpectoral dissection were assigned to the T/SP group, five who underwent oblique skin incision along the rib and bar insertion through a suprapectoral dissection were assigned to the O/IP group, and four who underwent oblique skin incision and subpectoral dissection were assigned to the O/SP group. Each patient in the T/SP group underwent the operation by a different surgeon, two of whom were the authors, including the first author; the first author performed all operations in the O/IP and O/SP groups. The first author evaluated the shape of the developed breasts using the frontal- and oblique-view photographs. We also investigated the location of the lateral border of the mammary gland in seven other adolescent and adult female patients using three-dimensional computed tomography images. Results Lateral depression of the breast occurred in four of eight breasts with a transverse incision, and flattening of the lowermost portion of the inframammary fold occurred in six of 10 breasts with suprapectoral dissection. None of the eight breasts with an oblique incision and subpectoral dissection exhibited deformities. The lateral border of the mammary gland was on the fifth rib in five patients and on the fifth intercostal space in two patients. Conclusion An oblique lateral thoracic skin incision along the sixth rib and subpectoral dissection may reduce the occurrence of breast deformity.