So if you go back to the '80s, what did a muscle flap actually look like before the Mathes and Nahai classification?

It was empirical.

We knew that the, uh, gastrocnemius had a proximal blood supply.

We really didn't know much about the, uh, blood supply to the soleus other than there were, there was more than one vessel.

What we knew about the latissimus, for example, and the pec major was that you could base the latis- latissimus on the, uh, thoracodorsal, swing it anteriorly for breast reconstruction.

We knew with the pec major, especially taking care of infected median sternotomy wounds, that you could base it on its, uh, major, uh, proximal blood supply and turn the flap into the chest.

Once we had done those dissections, and I think the X-ray that you showed of the latissimus and the pectoralis showing that in addition to the major vessel, there was segmental vessels to those muscles- Then we started, instead of doing a complete pec major transposition for the infected medium sternotomy wound, we started doing the segmentally based turnover flap of the pec major.

So there are certain principles that have really stood the test of time.