Mary,
I would not recommend dead lifts for you at this time, if your back gets better either naturally or threw surgery then that's another story.
One exercise that comes to mind at the moment, is hamstring curls, with ankle weights, stand behind a chair with legs shoulder width apart, legs slightly bent, now you have two positions depnding on how tall you are and how short or tall your chair is. You can either leand down with back straight and cross arms over the back of the chair and lean on your cross arms. Or you can lean over more, and put your hands on the seat of the chair, and keep elbows slightly bent and hold yourself up that way. Once you are in a comfortable positon where your arms will support some of your weight and balance and have a straight back. Raise one leg up and straight back, the height isn't as important as tensing and stretching the back of the raised leg. You don't ever want to lift you leg up high enough that it's causing you to arch your back to get it up there. You standing leg may feel a little bit of tension if it doesn't feel good bend the knee a bit more and put more weight on your arms. Okay your now in position for a hamstring curl. If you've done bicep curls you know how to do it, just it's your leg and not your arm, that will be going up and down. Keeping the leg as high and tight, now stablize where your leg is right now, you don't want the upper half of the leg to move at all. Just like you don't want the upper half of the arm to move at all when doing the bicep curl. But you do want tension on that upper muscle all the time. Now that you got you body holding the leg in place, simply bend the knee and bring the foot up as high as you can get it, the whole time tensing and squeezing the hamstring. Try a few of these with no weight and get the feel of them as well as correct form. Once you got the form then use an ankle weight that is heavy enough that your hamstring will be tired after 12 reps. If you don't have an ankle weight use a stretchy band. You should tie one end onto your standing leg and then tie it to the calf or ankle of the leg you are going to work. You should have the two legs tied some where between 18 inches and 2 feet. And then simply switch legs, and you should see if you can do as many hamstring curls as Cathe does dead lifts.
This is one exercises that popped into my mind if you have trouble or want a different just ask, I got to head home in a minute but I wanted to get something out to you.
Kit
) However, I have a degenerated disk in my lower back, and need to be very careful. I am leery of deadlifts. Do you have any suggestions for a good substitution excercise I could do?