Cubital tunnel transpostion surgery versus ulna nerve surgery

Is there a difference and how do we know which is correct?

I have had this severe pain going on 3-4 months now and the first doctor has been taken his sweet time with test.
I finally went back to my orthopedic who did my knee surgery and he knew within our first visit that this was a pinch nerve so to speak. My pain is getting worse and I am losing all strength in my left hand and arm due to delay in help.

Does anyone recommend therapy first after 3-4 months of pain ?or just relieve the pressure on the nerve.