Determination of the lateral extent of the subcutaneous wound bed in canine cadavers after closure of skin defects to replicate tumor excision.

Abstract

To determine the extent of subcutaneous involvement after primary closure of experimental skin defects. Experimental study. Eight large, mixed breed dog cadavers. Standardized, circular skin defects with diameters of 2, 4, 6, or 8 cm were created at the lateral thorax or abdomen by using a matrix to ensure even distribution, with eight defects of each diameter. The wound beds were covered in 60% barium sulfate paste prior to primary closure. Computed tomography and a dedicated viewing program were used to measure the distance from the edge of the subcutaneous defect to the incision at set intervals along the incision. The mean ± SD maximum lateral extension was 6.4 ± 1.9, 14.1 ± 4.9, 18.5 ± 6.9, and 26.0 ± 9.6 mm for 2-, 4-, 6-, and 8-cm defects, respectively. Extension >2 cm from the incision occurred in zero of eight, one of eight, five of eight, and six of eight defects after closure of 2-, 4-, 6-, and 8-cm defects, respectively. Extension >3 cm from the incision occurred in zero of eight, zero of eight, two of eight, and five of eight defects after closure of 2-, 4-, 6-, and 8-cm defects, respectively. The lateral extent of the subcutaneous wound bed extended past previously recommended revision margins of 2 to 3 cm in some defects measuring greater than 4 cm in diameter. Surgeons and radiation oncologists should consider the potential extent of the subcutaneous defect when planning revision therapy, especially after large resections.