Soccer players have a good initial rate of return to play following ACL reconstruction which declines over time, although many athletes are still playing years after surgery. Younger and male soccer athletes are more likely to return to soccer after ACL reconstruction while graft does not appear to have any impact on return to play. Males may be affected more directly than females by the injury itself as opposed to other factors or life events in terms of their potential return to play. There is a high risk of recurrent ACL injury in these athletes, particularly in female soccer players and those who injure their non-dominant leg.
Previous studies have shown results similar to ours. A recent study of ACL injury in high level soccer athletes from Europe reported 94% return to play within 10 months,33
with no long term follow-up. A study of 118 soccer players who underwent ACL reconstruction with iliotibial band autograft reported that 68% of athletes were still playing soccer at a median follow-up of 4 years.4
Return to play occurred at a median of 7 months (range 5–24 months) in this cohort. A survey of over 300 soccer players from Sweden reported that only 28% of male and female soccer players were playing soccer three years out from ACL injury.28
Four years later, only 25% of men and 7% of women were playing soccer in this cohort. However, only half of these athletes underwent ACL reconstruction. Among those who received surgical treatment, 26% of males and 12% of women were still playing at 7 year follow-up.
A few studies have looked at the effect of gender on outcome after ACL reconstruction in the general population. A prospective study comparing ACL outcomes by gender among athletes in various sports found greater laxity and some strength deficits in females compared to males after reconstruction using hamstring but no differences when using bone patellar tendon bone.18
Two additional studies found no significant gender based difference in outcomes after ACL reconstruction with bone patellar tendon bone in all comers.15,25
Large general cohort studies have not reported any effect of gender on outcome after ACL reconstruction.29,31
In our cohort, female soccer athletes are less likely to get back to soccer than their male counterparts. The reasons for this are probably complex as women were less likely than men to attribute their ACL injury as the primary reason they were no longer playing soccer. Nevertheless, female soccer players should be made aware of this information prior to surgery, particularly if return to play is a primary motivation for the surgery.
The general consensus in the literature is that outcomes from BPTB and hamstring autograft are very similar.7,22,24
A recent case control study comparing BPTB with hamstring autograft in the young athlete found no difference in return to play between the two grafts.24
The recent study of ACL reconstruction in elite European soccer players reported no difference in time of return to play between the two grafts although the percentage of athletes getting back to soccer was not reported by graft.33
In our study, there was no significant effect of (auto)graft choice on return to play in soccer athletes.
We are not aware of any previous study reporting the effect of leg dominance on outcome from ACL reconstruction in soccer athletes. Our finding that 57% of ACL injuries occurred on the dominant limb is similar to the findings from other studies. In the recent study of elite male and female soccer players from Europe, half of the ACL injuries occurred in the dominant leg.33
Another study of male soccer athletes reported that 50% of ACL injuries occurred in the dominant leg.14
In a German study of injuries in their female national soccer league, 69% of the ACL injuries occurred in the dominant leg.13
Although the dominant limb ACL may be at slightly higher risk of injury, our data suggests limb involvement does not have any impact on return to play in soccer athletes.
The reasons for not returning to play after ACL injury and reconstruction differed by gender in our cohort. The majority of men attributed their ACL injury as the primary reason they did not return to soccer compared to only one in four of the women. There are a number of possible explanations for this discrepancy. Men may find the injury and surgery more traumatic and/or painful and be more averse to repeating this experience. Conversely, women may be more likely to limit their participation due to other external factors such as graduating from a certain level of schooling or starting a career or family. Although a previous study reported that fear was the primary factor for not returning to play in 24% of athletes who underwent ACL reconstruction,21
this area deserves more investigation both for soccer players in particular and athletes in general.
There was a high rate of subsequent ACL surgery in this cohort, especially in females and on the contra-lateral limb. These rates are similar to those reported for the general population.29,36
In our study, the higher rate in females may be at least partly explained by the younger age of the female cohort. The limited events (i.e. further surgery) precluded a multivariable analysis; therefore, the univariate statistics reported are not controlled for age and activity level previously shown to predict ACLR graft failure.5
Only a multivariate analysis can control for age and Marx activity level that have been previously shown to predict ACLR graft failure.5,20
This would require more subsequent surgeries than reported in this study.
Soccer athletes who injure their non-dominant limb are at higher risk of injuring the ACL in their contra-lateral dominant limb in the future. The reasons for this relationship are not clear. Perhaps the injury and reconstruction create or increase neuromuscular differences between the limbs. Injury to the non-dominant limb may lead to even greater dependence on the dominant limb during play, potentially increasing the risk for future injury.
Fortunately, there is a growing body of evidence that ACL injury prevention programs may be effective in soccer athletes.6,16
It may be particularly important to evaluate these programs in soccer athletes who have already undergone ACL reconstruction, especially females and athletes who injure their non-dominant leg, as they appear to be at heightened risk for recurrent or new injury.
The limitations of the current study include a dependence on subject recall at the time of follow-up which is more likely to be variable on level of performance, time interval until return to play or reason for not returning than whether they returned to play. The cohort includes a relatively limited number of athletes and may not be large enough to provide definitive results for all of the studied comparisons. Prospective data may yield slightly different results when asking on performance when they returned to play or all the reasons why they did not. Furthermore, this cohort study was not adequately powered to perform a multivariable analysis of risk factors (predictors) on subsequent surgery. In addition, we do not know the expected rate of continued participation in soccer for athletes who do not injure their ACL. For example, what percentage of 27 year old soccer players with intact knees are still active in the sport 7 years later? Despite this limitation, the information is still relevant for soccer players who do injure their ACL and undergo reconstruction as it predicts the likelihood of their future participation in the sport.
This study represents a large, long term follow up of return to play in soccer athletes following ACL reconstruction. These athletes can get back to play despite the decline in participation over time. Younger and male soccer athletes are more likely to return to play after ACL reconstruction. There is a high risk for future ACL injury, especially in female soccer players, and ACL reconstruction in the non-dominant limb may increase the risk for future ACL injury in the dominant limb. Soccer players who undergo ACL reconstruction may benefit from and be the ideal population for targeted injury prevention programs. More research and a larger population of soccer players is needed to study more potential variables that impact return to play initially and over time in these athletes and subsequent ACL surgery.