I agree with liege about the Pendlays. Wait until your lower back is healed up, then start doing them.
If you are new to them, you'll obviously have to use lighter weight - just like any other exercise - but that's what you should do to start out anyway. That way you can master the form. A lot of people think they are doing Pendlay's but they aren't. Unless you can easily return the bar to the floor when you lower it, without having to lower your torso in order to do so, then you probably aren't using good form.
And if you start out doing Pendlay's right from the beginning, then it's a good bet that you won't have any lower back problems for the rest of your life. I've done them from just about the beginning, and even when I wasn't doing them strictly, I was still at just about 90 degrees - none of that 45 degree crap - and my lower back is pretty much invincible now. Lower back is almost never the limiting point for me in a movement. In fact, this is probably the reason why I was able to handle squats and deads in the same day for such a long time.
But... if you don't care so much about lower back strength and just want your back to look good, then you can try doing 45 degree rows or seated rows instead. But... unless you compensate by doing a lot of deadlifting, I doubt you'll get erectors so huge that it looks like you could run a river between them, build a dam at the bottom and use that to power the entire continent of Asia.
