Extension of the musculocutaneous flap by surgical delay.

The musculocutaneous flap has limits on survival of its skin segment. Random skin extensions beyond muscle margins have, by clinical experience, been shown to survive. It has not been proved, however, what quantity of random skin will survive or whether its viable dimensions can be augmented by surgical delay. Twenty-five porcine musculocutaneous island flaps were created with a random skin extension running beyond the likely limit of survival. Twenty-five paired contralateral flaps subjected to a surgical delay one week earlier were raised simultaneously. The surviving dimensions of random skin on both control and experimental flaps were measured 14 days after delay. The control flaps sustained random skin segments one to 48 times their area of muscle while the delay doubled this, engendering more predictable survival. A new, successful experimental technique of increasing skin survival in musculocutaneous flaps is documented.