A research fellowship is a great back-up plan...especially for the applicant that had some red flags on his application (e.g. low Step 1 score, low clerkship grade, etc). In a sense, it is like an opportunity to redeem yourself and show that you are not throwing in the towel, that you will work hard and fight until you get in.
HOWEVER...it is important to keep in mind that a 1-year position will not offer much of an advantage for the following reason: you will have only 2-3 months to try to publish and be productive, which in reality is not practical. Nobody you work with can give a very credible LOR after only working with you for a few weeks. Therefore, if you're going to take this route, I would recommend a 2-year position. This would allow you ample time to work on many projects and publish several papers in time for the application a year later. Also, during this time you will be able to build contacts and connections and might even find a window to do an away rotation. Getting into ortho the 2nd time around will be an uphill battle for most reapplicants. You really need to present a whole new package for programs to give you serious consideration.
That's my 2 cents.
