Around 1998 I started having sever pains in my left side from neck to bottom outside of my shoulder. This eventually spread to my left hip and outside back of my leg. Back was fine though. Then the numbness started. My left arm all the way to my fingers would tingle and go numb. Same with my left side down my hip and leg. It finally got to the point where I could tilt my hip in a certain way and it would send electric jolts all over my left side along with tingling and numbness. The pain would still be there. If I sat on the edge of a chair, it would immediately cause pain in both arm and leg along with the electric shock and tingling. This lasted until about 2003, driving me to tears constantly.
I changed my sitting habits, bought a secretaries chair with swivel back, started watching how I stood, etc and it seemed to lessen and eventually disappeared. (except for some occasional episodes that would last several weeks.
Last year I started work in a warehouse (I'm 56 and have always been strong). Within 6 months of this heavy labor I started having these problems all over again. I could no longer grasp the boxes, with my left arm losing it's strength along with numbness and the electric shocks. My hip, leg and lower back would just give out. I eventually quit that job because I could no longer perform. Now, after 3 months of not working and hoping to heal, I am having shooting pains down my left shoulder and arm. I again can tilt my hip and set my whole left side jerking with the electric shock feeling. I have to keep my head bowed to my chest to relieve the pain in my neck and shoulder.
Since this affects both the upper and lower extremities, it is most likely a problem in the cervical spine region. Again, since it involves such a large area, it is probably not just one or two peripheral nerves, but may instead be a problem with your spinal cord itself. This could be from one or more discs in the cervical region pressing on the cord.
Sounds like you need to be seen by an orthopedic spine surgeon, a neurosurgeon, or a physiatrist (a specialist in PM&R - physical medicine and rehabilitation). A thorough physical exam and possibly some studies (x-rays, MRI, CT, electrical studies) some discover what your problem is.
I have heard about problems in the arm, neck region steming from the c5 and c6? - but it's the leg stuff that threw me off. Plus the sitting on the edge of a chair thing. I know I didn't have the best posture growing up, so when I made changes in the way I sat, stood, etc and felt improvment - I just naturally thought I had corrected the problem. The heavy work I was doing lately may have brought it all back.
I'll see if I can get a physical done pronto and cross my fingers for a good report.