Can a pinched nerve cause numbness in entire keft side?

Not usually: Pinched nerves follow a specific pathway of pain in what is called a dermatome. These are isolated and well mapped in human anatomy. A pinched nerve usually affects one part of an arm or leg or specific part of the body, not an entire side of the body.

Not one pinched : Nerve. A pinched nerve can not cause numbness in the entire left side of your body. Each nerve have a certain small area of the body where they supply sensation.