Is Stem Cell Therapy for ACL Tears a Silver Bullet?

The rationale and indications for stem cells and other biologic injections for joints and injuries is sound, but the devil is in the details

By Dr. Semon Bader


Recently quarterback Ryan Tannehill re-injured his knee during practice while running down field. In January he suffered a reported partial tear to his ACL (anterior cruciate ligament) during a Miami Dolphins playoff game. He elected to have his injury treated with rehabilitation and stem cell injections in the hopes of avoiding ACL reconstruction surgery.MOS | Football Injuries | Stem Cells Therapy for ACL Tears

His attempts to avoid surgery failed and he ultimately elected to have surgery earlier this month. Unfortunately, he will now miss the entire 2017 season, rather than possibly being recovered from a surgery that he could have had done in January. Did he make a bad decision?

Stem cell injections and other biologic injections such as platelet rich plasma (PRP) have gained much attention in the last few years as potential alternatives to surgery. Many professional athletes have brought attention to these “cutting edge” injections with hopes of enhancing or extending their careers.

So, what is the reality? Are these injections the fountain of youth or silver bullets to allow athletes and others to avoid surgery?

In a nutshell …hopefully someday they will, but the jury is still out on the optimal utilization and formulation of these injections. However, I and many other physicians are optimistic that someday these nonsurgical strategies will replace or improve current surgical techniques. The reality is that we are still working out the details with respect to which injuries are most reliably treated with injection-based therapy and which are not.

Learn about ACL reconstruction

In an ACL tear, the ligament loses tension like a stretched out rubber band

Currently we know that conditions like tendonitis and arthritis can be very effectively treated with these injections. However, injuries such as ligament tears still pose a challenge. One major hurdle is the mechanics of ligaments.

Once torn, a ligament loses it tension much like when a rubber band is stretched out. The torn ligament must be pulled into position to function effectively. It is challenging do this without physically putting the ligament back into position or replacing it.

Partial tears or sprains could be the first categories of injuries that injections can be used for, as we learn how to best utilize these less invasive treatments. Tannehill was reported to have had a partial tear, but unfortunately even his injury failed to fully heal with these injections and rehab. His decision to avoid surgery and use stem cells was a reasonable one with the information and techniques we have these days, but there is clearly room for improvement.

So, for now beware promises of miracle cures or alternatives to surgery without understanding the rationale for these alternatives. There are many variables to take into account aside from cost, including reliability and the potential downsides.