I ve had muscle spasms in my lower back for a month. I ve remained active, started Pilates again to strengthen my core muscles, I ve used heat, muscles relaxers (I stopped using them during the day a week ago) I take 8mg of Tizanadine for sleep at night, and I continue to stretch throughout the day, as well as light core exercises. The spasms continue. I ve never had back spasms continue for such a long time and I am wondering if I should be concerned that something else is occurring. I had gastric bypass surgery June 21, 2016. I ve lost 55lbs, and I find this issue to be puzzling. Thanks for any advice you can provide.