Most NFL Players Return to Competition After ACL Injury, But at a Reduced Performance Level

Performance of wide receivers, running backs post-ACL injury falls by one


Nov 30, 2006, 00:00 ET from American Orthopaedic Society for Sports Medicine

    ROSEMONT, Ill., Nov. 30 /PRNewswire/ -- The good news for NFL players
 who sustain an injury to their anterior cruciate ligament (ACL) is that
 they'll likely play again in the NFL. The bad news is, they'll return with
 diminished performance on the field, concludes a study in the December
 issue of The American Journal of Sports Medicine.
     "Although there have been over 2000 articles on the ACL in the past 20
 years, only a few have focused on the pro player," writes author James L.
 Carey MD and colleagues from the Department of Orthopaedic Surgery,
 University of Pennsylvania School of Medicine, Philadelphia, Pa. "Our study
 is the first to objectively measure an NFL player's performance before and
 after an ACL injury." (Dr. Carey is now affiliated with Vanderbilt Sports
 Medicine, Nashville, Tenn.)
     Brian J. Sennett MD, co-author and Chief of Sports Medicine at the
 University of Pennsylvania, believes "this article will have significant
 impact on setting appropriate expectations for the injured players, their
 agents, team owners, and fans. It is the first article to establish that
 injuries may have a significant negative impact on a player's performance
 if they are able to return to action."
     The researchers collected data on ACL injuries sustained by NFL running
 backs (RBs) and wide receivers (WRs) during a five-year period (1998-2002).
 This data came from NFL game summaries, play-by-play documents, weekly
 injury reports, and player profiles. The injury group was compared to a
 control group consisting of all NFL RBs and WRs without an identified ACL
 injury who played during the 2000 season.
     Carey, Sennett and colleagues devised a unique measurement of game
 performance output in the professional athlete. They assigned a "power
 rating" for every player in every season, defined as a weighted sum of
 total yards and touchdowns, likely the most important statistics of RB and
 WR performance. The power ratings for the 3 seasons prior to ACL injury
 were compared to the power ratings for the 3 seasons following ACL injury.
     Data were analyzed for 31 players with 33 ACL injuries. Of the injured
 players, 21 percent (7 of 33 ACL injuries) never returned to play in
 another regular season NFL game. Of the 79 percent that did return, most
 players returned to action 9 to 12 months after an ACL injury.
     For those players who returned to NFL action following an ACL injury,
 performance fell by one-third, the researchers found. Power rating per game
 played decreased from 9.9 pre-injury to 6.5 post-injury. This decline in
 player production was statistically significant when compared to the 146
 players in the control group.
     Knee pain, stiffness, loss of strength, deconditioning and reduced
 proprioception (the sense of knowing where your leg is) may be factors
 explaining the loss of production in players after an ACL injury, the
 authors theorize. Further, ACL reconstruction does not perfectly recreate
 the complex anatomy and composition of a person's ACL before injury.
     Interestingly, prior to their injury the ACL-injured players performed
 better than did controls. "High-performance RBs and WRs are more likely to
 be injured because they compete in more plays per game, carry the ball
 longer on each play, and attract more defensive attention," the authors
 say. "The same qualities of RBs and WRs that contribute to high performance
 -- instantaneous decelerations as well as explosive pivoting and cutting
 maneuvers -- may increase the risk for ACL injury."
     The researchers cite a recent survey of all 31 NFL team physicians who
 were asked to quantify "what percentage of players return to play in the
 NFL after ACL reconstruction." Ninety percent of team physicians responded
 "90 to 100 percent" of players (assuming not borderline talent) return to
 the NFL. The current study found the number of players who return to play
 after an ACL injury was actually less, at 79 percent.
     "Most studies report good to excellent results in the majority of ACL
 reconstructions regardless of technique or patient age, but the
 professional football player presents unique demands on the reconstructed
 knee," Carey concludes. "Our findings may be useful for athletes, coaches,
 and team owners in anticipating the future contributions of a player who
 has injured an ACL."
     The American Journal of Sports Medicine is the monthly peer-reviewed
 scientific journal of the American Orthopaedic Society for Sports Medicine
 (AOSSM). AOSSM is a world leader in sports medicine education, research,
 communication, and fellowship. The Society works closely with many sports
 medicine specialists and clinicians to improve the identification,
 prevention, treatment, and rehabilitation of sports injuries. Please visit .

SOURCE American Orthopaedic Society for Sports Medicine