Loose-fitting sweatshirts with large arm sleeves are a good alternative to a regular dress shirt. Dress shirts are front open but they are also expensive to replace if you have to cut them up while you are recuperating.
A sweater is another option as these can be very loose-fitting. Plus, they are very stylish so you can look good whenever you go outside. If you are an athlete or like to participate in team sports for fun, warm-up tops are another option you have available.
Pajama tops can be considered as well. If you are not going anywhere, these are very soft and flexible giving you lots of maneuvering room. If you put your mind to it, you should be able to come up with lots of good options.
They say to avoid zippers but zippers are easier to manage than buttons. Also, go with what feels comfortable next to your skin. You already have enough pain and other issues to deal with so it makes sense not to add more to your situation.
Lastly, you can always visit www.renovamedicalwear.com for you post surgery clothing needs.