Every Once In A While A Couple Times A Day

Every once in a while a couple times a day my back will pop somewhere on my lower spine and then I will get a feeling like an electric shock. This pain radiates and not to any specific area, it is different every time. I have had it go down my legs and then I am down on one knee. I have also just had it radiate to my upper back or to my arms. I have no idea what it could be.