As author of The Arm, Jeff Passan is the expert on all things elbow and shoulder in the baseball world.

Passan’s latest for Yahoo! Sports profiles Los Angeles Angels pitcher Garrett Richards, who is attempting to come back from a torn UCL without undergoing Tommy John surgery.

What’s Richards’ secret? Would you believe orthobiologics? Here’s the story:

[The] 28-year-old is the latest player to turn to orthobiologics, the class of treatments that includes stem cells and PRP, in hopes of healing an injury. While clinical studies have shown great success with those who use orthobiologics, they are not yet a panacea for the pervasive elbow injuries in baseball for two reasons: They work only on partial ligament tears, like Richards’, and medical studies have yet to validate their efficacy independent of other treatments run concurrently.

Long story short: It’s complicated stuff.

Richards, for his part, is evidently back to throwing in the upper-90s -- and wants to throw 200 innings this season. That’ll be difficult since, per Passan, the Angels will cap his outings at 100 pitches. Of course, whatever the Angels get out of Richards is gravy -- had he undergone Tommy John surgery last May, he would’ve been out until the second half of the 2017 season, if not longer.

Whether Richards makes a full recovery could determine the future popularity of this procedure. Teams are undoubtedly seeking ways to keep their pitchers from undergoing the lengthy rehab process that comes with elbow surgery, and while this seems borderline science fiction, it’s probably none more so than the actual UCL replacement operation itself.

In that sense, Richards is an important figure in 2017. For the Angels’ season, yes, but also for the future of pitchers with torn UCLs.