DEVELOPMENT OF A FREE LATISSIMUS-DORSI MUSCLE FLAP IN CATS

Anatomic and experimental evaluation of the feline latissimus dorsi mu scle was performed to assess its potential use as a free muscle flap. In the anatomic study, nonselective angiography of the subscapular art ery was performed in nine heparinized feline cadavers. The muscle dime nsions and vascular anatomy of the dissected latissimus dorsi muscle w ere recorded. In the experimental study four cats underwent heterotopi c transplantation of a partial latissimus dorsi flap, and three cats u nderwent orthotopic transplantation of a complete latissimus dorsi fla p. The mean length and width of the latissimus dorsi muscle was 19.0 a nd 5.4 cm, respectively. The dominant vascular pedicle was the thoraco dorsal artery and vein. The average length and diameter of the thoraco dorsal artery was 2.7 cm and 0.6 mm, respectively. Minor vascular pedi cles were provided by branches of the intercostal arteries. Numerous c hoke anastomoses existed between the two pedicle systems. Viability of muscle naps based on subjective evaluation, angiography, and histopat hology, was 66% and 100% in the heterotopic and orthotopic studies, re spectively. Flap failure seemed to be caused by both arterial and veno us thrombosis. The latissimus dorsi muscle flap met criteria required for application in microvascular reconstruction. The vascular pattern was appropriate and consistent. Donor site morbidity was low, whereas surgical accessibility was high. The muscle satisfied the physical cri teria of a free flap. Long-term anastomotic patency and flap viability was shown. (C) 1996 by The American College of Veterinary Surgeons.