I don't think you'd have many problems, you were only gone 4 months and not exactly sitting on your ass all that time.
You could probably pick any routine just cut back on the workload for the first week and see how you go. So instead of doing 4 sets, do 2 sets (as an example) just for 1-2 weeks and see what happens.
You might find you get back to full strength really quickly.
What you do not want to do is launch yourself into something at full workload, and do fine, for a week or two, then after a few weeks realise you are really overloading without realising it, and burn out.
After a break, sometimes you come back and you have tonnes of energy and go overboard, even if your poundages are not as high.
At least, this is my experience.