Watch the T-Bone's Choice Cuts: 2 online guitar lesson by David Blacker from Swing Blues Survival Guide: Rhythm

One thing you can do with this T-Bone C9 chord voicing is incorporate the high E string on the 8th fret, extending the C9 from the A string all the way up to the high E. Typically, T-Bone incorporates the high E (and B string sometimes) as a little after accent after playing the main meaty part of the chord on the A, D, G & B strings. He grabs the high E & B strings (8th fret) to sort of punctuate the C9. You can experiment with this and sliding chords to come up with some cool vamps.