You can look on the medical forums for questions regarding doing a surgical residency at a later age. I'm not an OMS but it does appear possible to match into a program at that age if you have a competitive application; however, there may be some programs that will discriminate on age.
I think the most serious consideration you should have is will you be content with having a relatively short career as an OMS. It is the most physically demanding specialty IMO. Really think hard on if that specialty is for you at this stage in your life. If you determine that it is then go for it and don't look back.
