Return to Play After ACL Injuries

By Dr. Lawrence J. Lemak and Dr. William McGee on November 21, 2014 hst Print

One of the biggest challenges for sports medicine professionals is the decision about when to return an athlete to full participation after an injury, specifically one of the most serious injuries – a tear of the anterior cruciate ligament. The decision-making after an ACL tear has proven to be challenging and its complexity is often underestimated.

This incidence of ACL injuries has increased as more and more kids have become active in sports and are participating in significantly more practices and games than ever before. There are approximately 100,000 to 250,000 of these injuries per year in the United States, with girls being 2-8 times more likely to sustain this injury.

Surgical and rehabilitation techniques have improved greatly over the years, and the expectation now is that an athlete will return to his or her sport and to the previous level of performance. But how do you know when your athletes are “back” from this injury?

The goals of surgical reconstruction are to restore the stability of the knee and protect the athlete’s joint from further damage. Through intense rehabilitation, athletes attempt to return to their same level of sport and, in most cases, are successful. Every effort is made to reduce the chance of a repeat injury or an injury to the other knee.

Years ago after ACL surgery, patients spent weeks in the hospital and were placed in casts after having big, open surgeries. Now, surgery is mostly arthroscopic, patients go home the same day and are walking and putting their full weight on the operative leg immediately, and physical therapy can begin as soon as the day after surgery. Initial therapy is focused on controlling pain, swelling and gently restoring the motion in the knee. As patients progress, they begin strengthening programs, then incorporate agility drills and, finally, sport-specific training.

So, how long should all this take? This is the fundamental question that is asked by athletes, parents, coaches, media, fans – essentially everyone involved. Recently, it was reported in the media that this injury “usually takes about 4-6 months to recover.” This is a significant oversimplification of the rehabilitation process after an ACL surgery. Also, there are very few athletes, especially at the high school level, who have achieved the level of functional strength necessary to return to sports in that timeframe.

Several factors should be considered before allowing athletes to resume participation in their sport.

At a minimum, the swelling, range of motion, stability and strength all should have returned to normal. Particular care must be taken to ensure that the reconstructed ligament has not re-torn or become loosened over time. The athlete should be confident that the knee feels stable and has not altered the course of their rehab as they progress to higher levels of exercise. It is important that the athlete has approximately equal strength in both legs. The strength levels can be determined with simple techniques or with advanced computerized testing.

Strength alone, however, is an inadequate measure of determining when an athlete can safely return to his or her sport. The athlete should pass a series of functional tests as well. Once the aforementioned minimum requirements have been met, the athlete will be advanced to this very important and often overlooked phase.

The “hop test” has been used for a long time and can add to the evaluation. If the athlete can hop on one foot for distance three times, the same on each leg, this is good progress. More importantly, close attention must be focused on the quality of the movements. An important marker to watch is if the knee, on either leg, collapses in when the athlete is performing the test. This is a position of risk for re-injury. If this collapse is observed, it means the athlete still lacks the strength necessary to perform higher-level activities safely.

Other movements and exercises should be observed as well – activities such as jumping (both the takeoff and the landing), running (watching the knee position and equal weight on each leg), stopping and starting, and changing directions, or cutting (knee should not collapse in and the athlete should not tilt the upper body). These tests can be monitored by the physical therapist, who along with the physician and athletic trainer, can help determine if the athlete is ready to continue the progression.

Once the athlete has demonstrated a return of strength and can perform some of these basic movements, a program to re-integrate into his or her sport can begin. In the past, this phase has received little attention. Remember, an athlete coming off an injury needs time to adapt to the speed of his or her sport and also to develop the endurance needed to play the sport. The athlete may also feel uncertain about whether he or she can play without getting re-injured. This psychological aspect should not be ignored.

A progressive increase in time on the field can help with both of these aspects. All athletes should be educated on exercises and warm-up programs that have been demonstrated to decrease the risk of injury. The Santa Monica PEP program is one example and there are several others that have been researched. All athletes and especially those returning from an ACL injury should regularly participate in one of these types of programs. Unfortunately, the chance of a re-injury to the ACL is about 10 percent, and the risk of tearing the ACL on the other knee is also about 10 percent.

Coaches should be made aware of the athletes who are returning from injury, and some consideration should be given to identifying them in practices with a different colored jersey or other identifying methods so that their repetitions and activities are more easily monitored. Sport-specific plans can be designed but should begin with non-contact drills for a portion of the total practice time, followed by an increase in workload. If the player shows good progression and no setbacks, contact can be introduced at a reduced amount of time compared to non-injured players. Game minutes or plays should also be monitored in the initial return to the field and increased over time to allow a safe return. With the time that the player has been away from sport participation, he or she will need to develop endurance, as fatigue can increase the risk of injury.

The successful return to the field for an athlete after an ACL injury is dependent on a technically sound surgery and an intense rehabilitation program with excellent compliance by the athlete. Good communication between the physician, physical therapist, athletic trainer, player, parents and coaches can help ensure a smooth and safe transition back to full participation.