It was not that long ago that an athlete's career was over if he or she "blew out" a knee (mostly referring to ACL injuries). It's a traumatic injury with a difficult rehab process that once had poor long-term results. Thankfully, athletes—like Adrian Peterson—now regularly return to full form after an ACL injury, and at a surprisingly fast rate.
On Christmas Eve 2011, AP received a surprise he did not ask Santa for; he tore his ACL and MCL on the last day of the NFL season. The Vikings were not in a position to make the playoffs, which slightly softened the blow; but it was expected that AP would not return until the middle of the 2012 season.
Adding insult to the injury, precedent has shown that running backs who sustain ACL injuries rarely return to their previous form. An article on ESPN.com included a table listing running backs' numbers the year after their return from ACL surgeries, and Peterson has bested them all. In fact, in 2012 he became the seventh RB in NFL history to run for over 2,000 yards in a season. He fell just nine yards short of breaking the all-time rushing record. The strength of this return is completely unprecedented.
Not everyone will return to play like Peterson, but his performance proves that it is possible if you follow a dedicated rehab protocol.
Where to Start
After an ACL injury is sustained, it's obviously critical to find a qualified surgeon. To ensure that you receive the best treatment, find a sports orthopedic surgeon who specializes in knee injuries.
In most cases, ACL injuries are associated with damage to other structures in the knee, such as the MCL (Peterson also tore this) and the meniscus. If not damaged beyond repair, these structures must heal and swelling must subside before ACL surgery. This can take a few weeks. Other structures will be repaired during surgery if necessary, which can lengthen rehab time.
Immediately After Surgery
The early rehabilitative phase is similar for most individuals after an ACL surgery. It is important to protect the graft, manage swelling and pain, improve range of motion and resume walking when allowed. Your physician and physical therapist will heavily monitor this phase.
The Rehab Process
The two primary goals of rehab are to limit complications and progress to pre-injury status. This is achieved by increasing range of motion and re-building strength in the muscles around the knee, particularly the hamstrings. The athlete must then relearn movement patterns by teaching his or her muscles to fire in a coordinated fashion.
The final barrier is restoring confidence in the knee. Athletes must block out previous pain and fear of injury, and trust their knee in order to play at their previous level.
Peterson's Unique Case
Decreasing the time to return to play after an ACL injury starts years in advance of the injury. Someone like AP—no excessive body weight, extremely healthy and phenomenally strong—is predisposed to a quick recovery. This can also be said for Derrick Rose, Georges St. Pierre, Tom Brady and Wes Welker.
Peterson played a competitive game about nine months after his surgery. This length of time is not unusual. The difference was his performance. He immediately demonstrated the same speed, agility and power that had previously defined him as a player.
In a Chicago Sun Times article, Peterson explained that he put a heavy emphasis on the early part of his rehab, which can be frustrating for athletes. He said, ''If you're unfortunate to have that injury, don't talk about what you're going to do. Be about it and grind like you've never grinded before. If you have to be able to come back and be better than before, you can't take it lightly.''
In most cases, a therapist will focus on range of motion and muscle engagement exercises during the early phase of rehab. For Peterson and other highly-trained athletes, more advanced exercises with resistance can be performed earlier in the program, albeit with a highly monitored and controlled range of motion. Common exercises include:
Risk vs. Reward
An article by Kevin Wilk in the Journal of Orthopedics and Sports Physical Therapy discusses the concerns about accelerated rehab. They include damaging the graft (replacement ligament from another area of the body), failing to allow other structures to heal and potential long-term effects.
The question of whether it is appropriate or safe to accelerate rehab is a tricky one. The possibility of graft failure, secondary injury, tendinitis and other long-term side effects is real.
So, the athlete and therapist must ask themselves:
- How important is it to the athlete to not miss any time?
- Were other structures damaged that require additional surgery or time to heal?
- What is the athlete's training age?
- Could he or she squat and/or deadlift more than two times his or her body weight prior to the surgery?
- What is the athlete's motivation level and work ethic?
In the case of AP—nicknamed "All Day" many years ago—he was willing to work ALL DAY so that he could return to the NFL as the best running back in the league. This season, he defied all expectations.
Learn more about coming back from an ACL injury through STACK's Athlete's Guide to the ACL.