I talked to a Tigers' fan the other day and he asked me if I thought Bruce Rondon was like Joel Zumaya.

Bruce Rondon

Interesting thought. Each rank among the hardest throwers in the history of MLB. Both broke down with arm injuries as young relievers with the Tigers.
After that, though, they didn't have a lot in common.

Joel Zumaya

Zumaya had a shoulder issue, and some other uncommon arm issues not related to his elbow. He was groomed as a starter in the minor leagues, and then often muscled up and tried to throw as hard he could as a reliever, perhaps to live up to his "Voodoo Child" legend. He also had what pitching coaches refer to as a violent throwing motion.
Pitchers rarely return to form from shoulder issues. If they do become effective MLB pitchers again, it is as re-inventing themselves by become finesse-style hurlers because they can't throw nearly as hard.
Conversely, Rondon has been groomed as a closer from Day 1. His delivery is not violent. It's smooth and fluid. While he has had command issues, it hasn't been because has overthrowing.
Tommy John surgery is a medical wonder for pitchers with elbow injuries. Sports Illustrated reported this week that 124 MLB pitchers have returned from the surgery since 1989. Most have returned throwing as hard, and in sometimes even harder, than before Tommy John surgery.
So while the odds were strongly against a comeback for Zumaya, they are strongly for Rondon coming back as strong as ever, albeit it after a long rehabilitation program. He likely won't be the same, even under the best-case circumstance, until 2016.
My Column. Michigan Wolverines back on track for a spot in the Final Four: http://www.theoaklandpress.com/sports/20140322/michigan-wolverines-back-on-track-toward-possible-final-four-bid-pat-caputo-says