What's Next for Kiko Alonso Following His Knee Injury and ACL Tear?

According to NFL.com's Gregg Rosenthal, the Buffalo Bills announced that up-and-coming linebacker Kiko Alonso went down this week with a torn left ACL. Rosenthal adds that the injury occurred during a workout in Oregon.

The hits just keep on coming.

The news represents a devastating blow to the otherwise rising stocks of both Alonso and the Bills. At this point in the season, an ACL tear will almost certainly end the linebacker's 2014 season before it begins.

In the coming days, Alonso will likely undergo surgery to reconstruct the ligament—if he has not already. Then again, a concurrent medial collateral ligament (MCL) or meniscus injury—or both—might delay the operation for a few weeks to a month should Alonso's surgeon elect to wait for any swelling that may exist to subside before operating.

Either way, the lion's share of Alonso's procedure will probably constitute using a piece of his patellar tendon—the part of the knee a doctor hits with a reflex hammer—to replace his torn ligament. As significantly damaged ACLs do not typically heal very well on their own, an elite athlete usually needs to employ entirely new tissue in order to return to his or her previous level of competition.

After surgery, Alonso will start down the long road to recovery.

In the immediate post-operative period, the former University of Oregon Duck—along with his team of medical and physical therapist professionals—will surely monitor post-operative pain and swelling. Gentle strength, range-of-motion and cardio exercises will probably follow in the following few days and continue for the next several weeks.

Agility exercises—often taboo for the first two or three months because they may place too much forward or rotational force on the healing ACL graft—come next.

The specifics of ACL rehab protocols will differ from patient to patient, but all involve gradually rehabbing an athlete's leg and knee to their prior level of fitness while the new ACL cements itself into place within the joint. An athlete's specific limitations and needs will dictate the fine details, such as exercise types, number of repetitions and other subtleties.

Isolated non-contact ACL tears usually carry an excellent prognosis in the long run. Nowadays, even ACL tears with concurrent MCL or meniscal injury—a relatively frequent injury combination—can leave athletes with minimal limitations when all is said and done.

Nevertheless, a graft's need for a slowly increasing workload to ensure stability all but guarantees the aforementioned and unfortunate truth: Alonso will likely miss the entire 2014 season, one in which the Bills figure—or figured, depending on one's opinion—to be quite competitive.

After all, ACL recoveries generally range from eight to 12 months or more. The earliest conceivable, but incredibly unlikely, scenario—six months or so—sets Alonso's return for early January. Even Melvin Ingram's somewhat jaw-dropping, same-year recovery from a torn ACL in 2013 started in the middle of May—not early July.

Alonso also carries a significant injury history. He already faced offseason hip surgery this year, as noted by ESPN's Adam Caplan. Additionally, he spent most of 2010 rehabbing a previous ACL tear.

In short, while Alonso's significant rehab experience will prove extremely beneficial as he recovers from his most recent injury setback, he—once again—has a long way to go.

Dr. Dave Siebert is a second-year resident physician at the University of Washington who plans to pursue fellowship training in Primary Care (non-operative) Sports Medicine.

Follow @DaveMSiebert