Have severe back spasms with left leg numbness and tingling and pain, what causes this, also left leg sometimes gives out.

Pinched nerve. Your symptoms, in particular the left leg numbness/tingling/pain/weakness, strongly suggest a pinched nerve in your lumbar spine. If your symptoms are progressively worsening, you may even need surgery. See a physician for further evaluation and treatment options.
See an Orthopedist ! Most of your symptoms seem to be from the spine, due either to a disk lesion or arthritis, or both, with a nerve(s) getting pinched causing the tingling/pain with numbness. Severe pain/weakness may result in your leg giving out as well. Otherwise, the leg giving out maybe due toa knee or other joint problem, like a loose body in the joint. So an orthopedist to confirm diagnosis and treated.

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Experience bilateral leg numbness and tingling and heaviness during the night, no back pain or other pain or trauma. I have a slight neck crimp too.

? Herniated Disc. Time to visit your friendly neighborhood doctor to get this checked out. It may be the position you sleep in or you may have nerve impingement secondary to a herniated disc in your back. Peace and good luck. Read more...