I have lost the vastus lateralis muscle in my R thigh. I am 50 years old and noticed a slight dip in my thigh about 7 months ago. My Dr ordered an EMG and a MK untrasound. The EMG was normal, all nerve function was good. My ultrasound showed that there was no trace of the muscle. Both the radiologist and my Dr have never seen this before. My next step is to see a Neurologist but I feel that this may be a waste of my money, as I am on a limited income with minor health insurance I am still paying on the EMG. Have you ever known a muscle to completely disappear with no injury or illness reported prior to the occurance?