We paddled two laps of First Canyon, 17th ender through Waterfall, and had fun through the rapids, until we came to The Notch. After cruising through the entrance waves of The Notch, I reached the last wave of the rapid. This is also the point of the rapid where the river is most constricted and takes a small drop. I was paddling down the middle through the last wave in the rapid, which was a lateral wave that extended from the left bank upriver to the middle of the channel. I hit the wave and it flipped me to the left. There was a rock immediately downriver of the lateral that I landed on. My left hand, still holding my paddle, took the brunt of the impact. It broke a bone in my middle finger. I self rescued and paddled to river left where my paddling partner and I hiked out of the canyon to start our journey back to Anchorage.