Description: OBJECTIVE: To describe the location of the lateral thoracic artery (LTA), determine dimensions of an axial pattern flap based on this artery, and report use of this flap in 2 cats. STUDY DESIGN: Ex vivo study and case reports. ANIMALS: Cat cadavers (n=8); cats (n=2) with thoracic limb skin defects. METHODS: Dissection of the LTA was carried out on 1 side of each cadaver and the contralateral side was used for injection studies. In 4 specimens, the LTA was cannulated and injected with positive contrast material and the flap was raised and radiographed. In 4 specimens, the flap was injected with methylene blue. Adequacy of flap injection was subjectively evaluated and leakage of methylene blue from the cut edge was noted. RESULTS: The cutaneous location of the LTA caudal to the triceps muscle was confirmed. Mean flap size was 8.7 cm x 15.5 cm for a mature, average-sized cat. Perfusion of the entire flap was demonstrated and viability of the flap was confirmed in 2 clinical cases. CONCLUSION: The LTA flap is useful for repair of skin defects of the brachium and antebrachium in cats. CLINICAL RELEVANCE: The LTA flap is an alternative technique for repair of skin defects involving the thoracic limb of cats