Some places have a formal program set up, but at others it is just a matter of finding someone who will let you work with them (and can get you funding if you need it). I recall a few programs being mentioned last year. Here are a few threads to check out (though I don't know if these places will offer the same thing this year).
http://www.orthogate.com/forums/viewtopic.php?t=3137&highlight=research+fellowship
http://www.orthogate.com/forums/viewtopic.php?t=3058&highlight=research+fellowship
http://www.orthogate.com/forums/viewtopic.php?t=3054&highlight=research+fellowship
http://www.orthogate.com/forums/viewtopic.php?t=2983&highlight=research+fellowship
http://www.orthogate.com/forums/viewtopic.php?t=2314&highlight=research+fellowship

Also, I am sure some places will post opportunities around march like last year.

I was lucky enough to find a guy who lets me go to the OR (retracting and helping close mainly), shows me interesting patients in clinic, sent me to a conference (and hopefully to the acadamy meeting as well), and paid me (not a lot, but enough so loans can get paid). We have managed to submit 6 manuscripts that we started from scratch, and he plans to have me finish at least six more that we have in the works). Some people will be telling you to do a prelim year instead, but I think you should take a look at you application and try to target your year at improving the weaknesses. If clinical stuff is your weakness, do a prelim. For me, research was one thing that was lacking and it has been brought up in my interviews that I made a wise decision not to do a prelim year. Of course that all means crap if I don't match again. Good luck.

If you go to nearly any of the major academic centers for Orthopaedics, they will have labs that would love to take on an extra person for a year. That is, if there is funding. A one year stint means that they don't have to worry about letting you go if their funding runs out. If you give them enough time, they may even be able to get funding to support you (not sure if March to June is enough, though). You definitely don't need a formal research program, just a good CV and a lot of phone calls to make things work. You should have no problem finding a lab at a great program with great connections, great research, and a great experience for a year.

Anyone have track records for any of the research fellowships? I think a lot depends on whether your PI is willing to go the bat for you when comes matching time. It would suck to be left high and dry a second time around.