Well, you know it if you’ve had a fusion. You could be experiencing pain, burning, weakness, and more pain.
Everyone’s treatment will be a little different based on their surgeon’s protocol and your base line of strength and wellness. Please speak with your surgeon and make sure you are getting good quality physical therapy. This one exercise is the only one that I feel comfortable suggesting to the masses. Because you do it without moving your back or any back muscles. You can do it laying down, sitting, standing, wearing your brace. Get that core strong with a safe isometric exercise.