I have chills and shakes in the morning, please advise?

what can trigger chills and shakes in the morning for a 70 year old woman in decent health?
I have lower back pain and am scheduled for a Rhizotomy. Does not have a fever. Have never had the shakes like this in my life. Am stumped

FIND THE BEST DOCTORS NEAR YOU

Cardiologists – Cosmetic Surgeons – Dermatologists – Ear, Nose and Throat Specialists – Gastroenterologists – Gynecologists/Obstetricians – Neurologists – Oncologists – Orthopedic surgeons – Pediatricians – Psychiatrists – Pulmonologists – Urologists

The Fat Decimator System