Medicine factors in like any surgical specialty, you will need to know what to do with your patients once they get out of the OR and before they go in. The first few years of residency will be management of patients as they come in and out of the hospital. Aside from learning the basics of pre-op-ing a patient, your calls at midnight are going to be about Mr. Smith having high blood pressure or Ms. Smith having tachycardia and chest pain. You will need to know the basics very well.
As far as advanced management of patients, if you like managing arrhythmias and congestive heart failures and keeping people going physiologically, then ortho has very little of that. The most medical management you might do is as a ortho oncologist. Many people who go into ortho do so because they are not interested in the finer aspects of medical management. Rather they are interested in the finer aspects of anatomy and biomechanics. They like putting things together with their hands and seeing the results immediately. Administration of medications is not generally the forte of most ortho surgeons.
If you really enjoy medicine and the management of inpatients, making sure the entire body is working and that the physiology is correct, I suggest you really pay attention during your medicine and surgical rotations. That's probably the best time to get a feel for which style of patient management you think you are better at, and more importantly, which one you find more satisfying.
Good luck
