I had a quad tendinopathy a few years before my SFN started. I was an elite cyclist so this injury made sense. I even had Platelet Rich Plasma performed on my knee by a top sports med doctor. My knee tendon was healed according to the ultrasound, but my pain continued and my doctors didn't know why. The pain increased to the point where I limped most of the time.

From 2012 to 2014 also went through 4 different PT's, with the last therapist telling me that something is wrong with my knee because it should have healed already. Then in early 2014 it all came down very quickly - burning, pain, and electricity in my right leg that went body-wide. I think that SFN is hard to differentiate from tendon issues or muscle-skeletal pain.