THORACODORSAL AXIAL PATTERN FLAP

Axial pattern flaps are pedicle grafts which incorporate a direct cutaneous artery and vein at their base. The cutaneous branch of the thoracodorsal artery is the direct cutaneous artery for the thoracodorsal axial pattern flap. The direct cutaneous artery and vein extend along the length of the flap for a variable distance and the terminal branches supply the subdermal, cutaneous, and subpapillary plexuses. The thoracodorsal axial pattern flap is indicated for reconstruction of wounds of the ipsilateral thoracic limb and thoracic wall.

In a 2015 study investigating the outcome of axial pattern flaps in 49 dogs and 24 cats, postoperative complications were reported in 89% of animals. The most common complications included dehiscence (50% of axial pattern flaps in dogs and 75% of axial pattern flaps in cats), flap swelling (43% of axial pattern flaps in dogs and 50% of axial pattern flaps in cats), necrosis (46% of axial pattern flaps in dogs and 15% of axial pattern flaps in cats), infection (27% of axial pattern flaps in dogs and 40% of axial pattern flaps in cats), non-infectious discharge (14% of axial pattern flaps in dogs and 45% of axial pattern flaps in cats), and seroma (23% of axial pattern flaps in dogs and 20% of axial pattern flaps in cats). While the complication rate associated with axial pattern flaps is high, all of these complications were managed with either simple revisions (e.g., debridement and resuture) or conservatively (e.g., antibiotics, bandages, or monitoring). Overall, 93% of wounds were successfully reconstructed with an axial pattern flap. The flap outcome was assessed as excellent in 23%, good in 41%, fair in 30%, and poor in 7% of animals. The outcome following reconstruction using a thoracodorsal axial pattern flap was not specifically stated in this study, but two small studies have reported results following wound reconstruction with a caudal auricular axial pattern flap. In a 2003 study of 10 dogs, three dogs had 100% survival of their thoracodorsal axial pattern flap while seven dogs had partial necrosis of their thoracodorsal axial pattern flap (which ranged from 2% to 53%, mean 21%, of the flap length); while other complications included edema and bruising (eight dogs), infection (three dogs), seroma formation (two dogs), and partial wound dehiscence (two dogs). In a 2001 study of 10 cats treated with a thoracodorsal axial pattern flap in combination with an omental pedicle graft for the management of chronic non-healing axillary wounds, all cats had 100% survival of their thoracodorsal axial pattern flap and dehiscence was reported in two cats and a seroma in one cat. The mean area of survival of thoracodorsal axial pattern flaps in dogs was 84.7% in a 1991 experimental study.

Case 1 - Dehiscence Following Soft Tissue Sarcoma Resection