I have just married a wonderful woman with two teenage boys who are out of control. They have not been spanked in years and I think it is time to re-institute that form of discipline into their life; at least until their behavior improves. My wife agrees to abide by your decision and recommendations, as do I.
I do not know enough about the situation to able to give credible advice. What does "out of control" mean to you and your wife? What steps have been taken? Why, do you suppose, those steps have not worked?
Spanking is one tool available to parents to mold the behavior of their children. It works best when used with a variety of methods. I generally recommend that it be reserved for cases of violence, extreme defiance, or situations where a good consequence to bad behavior doesn't fit. It is not an instant fix; it is a deterrent to further bad behavior. As with all discipline, it needs to be used consistently and fairly.
There is nothing in the Scriptures indicating that spanking is only reserved for small children. There is no reason to stop when a child gets older if the child deserves a spanking. Generally, a child who is well trained when younger will few if any spankings when he becomes a teenager (Proverbs 22:6). However, a child left to his own devices will go from bad to worse over time (Ecclesiastes 8:11). Correcting have bad behaviors are allowed to become habits is very difficult, but it can be done if a parent is willing to work at it with a long term objective in mind.
The best thing to do is to work on one or two problems at a time. Select the biggest problem first, decide as a husband and wife team how to address the problem, and then implement the changes. When progress is seen, move on to the next pressing issue and work on that problem (without dropping the first). Over time you will begin to see major improvements.