After deciding to return for his senior season at the University of Georgia, quarterback and NFL draft prospect Aaron Murray went down in late Nov. 2013 with one of the more heartbreaking ACL injuries in recent memory.
Murray underwent surgery shortly thereafter, later tweeting that the operation went well. Over two months later, the former Bulldog is surely well on his way to recovery.
Unfortunately, Murray's injury occurred at a very inopportune time, precluding him from playing out the remainder of his senior year or in the Senior Bowl. That said, while the path ahead is certainly uphill, nothing yet suggests the injury will limit him in the long run.
According to The Macon Telegraph's Seth Emerson, Murray's injury occurred on the run. In other words, it did not involve contact to the knee.
Usually, an athlete suffers a non-contact knee injury when he or she suddenly cuts or jumps in such a way that stretches a ligament beyond its elastic capacity.
In the case of the ACL, motions that cause the lower leg to twist inward are frequently to blame. A sudden planting of the foot in an effort to quickly change directions is one common scenario. Leaping up into the air and landing awkwardly is another.
St. Louis Rams quarterback Sam Bradford's 2013 ACL tear is a prime example of a common non-contact case.
As seen above, a shove to Bradford's left side causes him to very subtly face a different direction relative to his momentum.
In other words, he pointed one way, but his movement continued in another. As a result, his knee buckled inward when he planted his foot on the ground, tearing his ACL.
Murray's injury mechanism likely somewhat resembled Bradford's. However, he continued to play through the original injury, according to a column by Emerson:
Aaron Murray "felt something pop" on his 28-yard run in the second quarter on Saturday night, according to Georgia head coach Mark Richt. It proved to be a torn ACL.[...]
Murray ended up staying in the game for 13 plays after tearing his ACL, completing a touchdown pass in the process, and completing 5-of-7 passes for 46 yards, as well as an interception, which proved to be the final pass of his Georgia career.
Emerson also noted that while Murray appeared injured, he convinced coaches and trainers that he could remain in the game by running on the sidelines.
Believe it or not, it is possible to play with a torn ACL, as lacking the ligament generally does not affect running in a straight line.
On the other hand, cutting, twisting and changing directions become much more difficult—if not impossible.
An athlete's pain tolerance also looms large, and an opposing player throwing Murray to the ground later in the game proved to be the final straw:
The above video clearly shows the hit spin Murray to the ground while also applying non-contact "valgus" stress—or inward-directed movement—to his already ailing knee, presumably causing extreme pain.
The possibility that the tackle completed a partial ACL tear also remains, though this is most likely a moot point. In order to maintain knee stability, athletes often need surgery for even an incomplete tear.
Fortunately, Murray sustained no other ligament or knee damage—as is often the case with non-contact injuries—and his prognosis is almost surely excellent.
Recently, thanks to improvements in surgical technique and rehabilitation science, isolated ACL tears are requiring less and less post-operative rehabilitation time compared to the past. A very unscientific, cursory survey of cases in the past year throughout college and professional football comes up with a very rough estimate of about nine to 10 months.
With that in mind, an average timetable puts Murray ready for action sometime in August or September of this year. That said, it is important to remember that ACL recovery timeframes can range tremendously and are dependent on the unique characteristics of each athlete and injury.
Until he receives medical clearance, the standout quarterback will do what he can to demonstrate his abilities.
According to ESPN's Joe Schad, Murray hopes to run through practice dropbacks and throws at his pro day in April—thereby presumably hoping to show he is regaining lateral motion.
In the end, the biggest drawback from his ACL tear may be his inability to work out on the field in hopes of improving that stock.
Dr. Dave Siebert is a resident physician at the University of Washington who plans to pursue fellowship training in Primary Care (non-operative) Sports Medicine.