My MP is only on the front of the thigh. I developed mine from
abdominal surgery.

People can develop MP from too tight compressive clothing...like tight belts, and jeans. Also it can come from compression along the spine (with or without back pain), as that is where the nerve comes from before entering the abdomen.

Also people who donate bone marrow, get needled in the back of the hip to reach the bone marrow in the pelvic bones. This procedure can also cause MP.

People vary in anatomical distribution of this nerve, at either L4 or L5. So surgical interventions may damage it or other types of medically invasive procedures.

Males can develop it on the side of the trousers where they carry their wallets.

There are many factors that can cause MP.

I used Lidoderm patches very successfully to block this severe pain, and never took narcotics or other drugs.
I applied them to where the nerve exits the abdomen under that ligament as illustrated in the link I gave you. After 2 weeks of every day use, the nerve went to sleep. So I have a remission now.