What are the indications for cross leg flaps in a modern microsurgical practice? Frank Hasting Hamilton described the first cross leg flap for lower extremity reconstruction in 1854, thus greatly expanding the ability to treat limb-threatening injuries. Since the introduction of microsurgery and lower extremity muscle flaps in the ‘70s and ‘80s, the uses of the various cross leg flaps have greatly diminished. For the current plastic surgery residents, the cross leg flap is primarily of historical interest.

In a microsurgery center with a high volume of lower extremity trauma, we developed a set of indications for cross leg flap utilization, including: 1.) free flaps that failed, 2.) a massive zone of injury with sub-optimal recipient vessels, and 3.) the danger of steal syndrome due to a single vessel runoff to the foot.

We present a series of patients that highlights complicated lower extremity salvage when local muscle flaps and microsurgical free tissue transfers are precluded. Expert knowledge of the various types of cross leg flaps and their indications must remain an integral part of the modern microsurgeon’s armamentarium.