What Causes Muscle Spasms On The Back?

Hello. My wife is 53 years old, and over the last 30 days has gone from mild muscle spasms in her back with little to no associated pain, to extreme and uncontrollable muscle spasms all over and extreme pain in her lower back. It s progressed over that time, and been acute for the past 10 days or so. Spasms are likened to convulsions really, impacting her entire body. Have visited ER 2 times, she was given valium and pain medication. Now the valium (10mg) only helps for approximately 2 hours, and she is experiencing significant weakening in her legs. CT scan shows only basic spondylosis and some degenerative disc disease but nothing that would cause these spasms. Gave antibiotic thinking of a UTI but she s had significant side effects and discontinued. White count was normal both ER visits. Seeing a neurosurgeon in the morning and scared to death.