Cumulative Sport-Related Injuries and Longer Term Impact in Retired Male Elite- and Amateur-Level Rugby Code Athletes and Non-contact Athletes: A Retrospective Study

The significant findings of this study were first, that across multiple injury types, past participation in rugby codes, particularly at elite level, is associated with a higher number of injuries, recurrent injuries, a continued impact of previous injuries post-retirement, and more than a twofold greater risk for osteoarthritis. Second, that concussion injury was the most commonly reported injury in both elite and amateur rugby codes, and was the injury with the highest cumulative load, indicating the highest rate of recurrence. Third, that the prevalence of current back pain and severe and regular joint pain was high for all former athletes, particularly former elite rugby code players. These data provide a strong basis for future research and intervention, for informing on player welfare both during, and post career, and offers important information to national governing bodies, and athletes themselves, on the cumulative injury load and risks in rugby codes.

Our findings add to the knowledge base on lifetime injuries sustained by rugby code athletes and suggest that for each season played, individuals are at risk of sustaining at least one injury. There were a high number of reported injuries per player, equivalent to 1.6 injuries/season in former elite rugby code players and 0.9 injuries/season in former amateur rugby code players compared with 0.2 injuries/season in former non-contact athletes. Our findings support those from rugby union injury surveillance studies reporting an average of 1.8 match injuries/player/season in the English Premiership [19], and from English Super League, reporting an average of 41 injuries/club/season [7]. It should also be considered that injury risk exposure levels will be greater for rugby code players at elite, than at amateur level, which is likely to explain the disparity in injuries/player by performance level.

The most common injury reported was concussion, followed by injuries to the back and to the knee ligament. The most frequently reported injury (total number of a given injury) was also concussion, followed by thumb sprain, and thigh contusion. This reflects recent injury surveillance data [7, 20, 21], and suggests that approximately 80% of rugby code players will experience at least one concussion at some point during their playing career, which, in the current study, spanned an average of 24–25 years. This is notably high in comparison to the data from earlier (pre-2005) injury surveillance studies [19, 22]. In the current study, past players were on average, exposed to rugby union or rugby league prior to 2010 when reported concussions in both codes were lower than for other injuries. The introduction of concussion laws (2012 for rugby union and 2014 for rugby league) is likely to have improved the reporting of concussion and there has been an improvement in the awareness of concussion as an injury. It is plausible to explain our findings based on increased awareness of concussion amongst past players retrospectively reflecting on their own experience of this injury in the context of current definitions and improved awareness. In addition, there is growing concern about the effects of cumulative concussive injuries to the brain [33, 34], and in support of this concern, our findings indicate that concussion is the most common injury with highest recurrence across a rugby code career.

Although it has been suggested that increased skills and technical proficiency can reduce the risk of certain types of injuries [35], we observed that in all cases where differences were statistically significant, injury numbers were higher in elite than in amateur rugby code players. We also found a higher recurrence of numerous injuries in elite rugby codes compared with amateur rugby codes (neck injury, biceps or triceps tear, knee ligament injury, PCL tear, and disc rupture or disc herniation). This suggests that there is no injury type for which there is a protective effect as skill level increases. Instead, a greater intensity of play, a more frequent exposure to risk of injury, and the financial need or desire to return to high-level sport, are likely to be more plausible explanations. The monitoring of injuries at the player level rather than at club level could be one approach to improving the management of injury for individualized player welfare. This could include a system by which the individual player’s injury history can be followed as they move across professional club contracts, and specific strength and conditioning and sports therapy strategies prescribed to help prevent recurrence of injury. In addition, the prescribing of individual player load and recovery relative to how the player is feeling or performing on a particular week would represent good practice.

Surgery data provided information on the impact and severity of the injuries experienced. The most common surgery reported was for meniscus tears, with approximately one-third of elite rugby athletes having at least one meniscus surgery and more likely to report long-term impact from this injury (RR 2.370, 95% CI 1.098–5.119). Although at a lower rate than in elite rugby code athletes, meniscus surgeries were also among the most common surgeries for amateur rugby code (18%) and non-contact (14%) athletes. This may reflect the involvement of the knee in sports that involve twisting and turning, including cricket, which was the main sport of our non-contact group. Overall, our findings do indicate that elite rugby code athletes are at a greater risk for sport-related surgeries than amateur rugby code and non-contact athletes, with surgeries more frequently involving the knee, shoulder and back (knee ligament injuries, ACL tears, shoulder dislocations, and disc rupture/herniation). Although cumulative injury loads were higher in amateur rugby code than non-contact athletes for several types of injury, the only significant difference in the occurrence of surgeries between these two groups was for ACL tears. This finding may indicate that there are notably more injuries in amateur rugby code athletes than non-contact athletes, but these injuries may not be to the extent that require surgery. However, there are numerous factors impacting upon whether or not an athlete has surgery for a given injury, with some injury types, such as ACL tears, more likely to require surgical treatment than others, and other factors, including the need or desire to return to high-level sport which is greater in professional athletes.

To understand the overall impact of injuries and surgeries, it is important to consider not only the injuries that occurred but also the long-term impact of those injuries, as evidenced by current ailments and whether injuries are still impacting these athlete’s, post-retirement. More retired elite rugby code players than non-contact athletes reported that they were still regularly affected by past sport-related injuries. Specifically, retired elite rugby code players attributed previous concussion, arm/hand/wrist fractures, neck burners/numbness injuries, shoulder dislocations, ACL tears, and knee ligament injuries, to an adverse impact on their current health status. Retired amateur rugby code players were also more likely to be still affected by concussions and general knee ligament injuries, specifically ACL tears, suggesting that the elevated risk of long-term injury impact exists at all levels of the sport. It should be considered that study participants reported injury severity in terms of surgeries and long-term impact, rather than recovery time, and therefore, it is not possible to compare these data to other published reports of injury severity in terms of exact time loss.

According to the Global Burden of Disease report, chronic back pain and osteoarthritis are leading causes of disability worldwide [36]. The occurrence of back pain and severe and regular joint pain was prominent amongst all former athlete groups, and the greatest occurrence was in elite rugby code athletes. It is unclear if the high prevalence of back pain in former rugby code players is related to vertebral injuries during their playing career [37]. However, it is notable that the reported prevalence of back pain (69–80%) or severe and regular joint pain (47–64%) in former athletes is higher than the prevalence of chronic pain or low back pain in the UK general population (43–48%) and specific to males (31.0–48.9%) [38, 39]. There is a need for future research to examine the underlying causes and implications of chronic pain in former athletes and to develop effective strategies for pain management in this population.

In addition to pain, the prevalence of medically diagnosed osteoarthritis was 2.3-fold higher in former elite rugby code than former non-contact athletes. Davies et al. [30] recently reported a fourfold higher prevalence of osteoarthritis in retired elite rugby union players compared to a general population cohort [30]. Although these results do not infer causation, reported medically diagnosed osteoarthritis was associated with previous joint injury, the total number of injuries, and previous sport injury-related surgery. These findings confirm that prior injury is a precursor to osteoarthritis [40], and together, these data suggest that retired rugby code athletes have an increased risk of developing osteoarthritis, which, at least in part, may be due to their higher rates of injury. As such, it is plausible to suggest that reducing the total number of sport-related injuries and surgeries in rugby union and rugby league may reduce the risk for osteoarthritis in later life.

This was the first study to describe the cumulative injury history and current physical health in former contact and non-contact sport athletes. There are several considerations to note hen interpreting our findings. First, as with similar studies involving the recruitment of volunteers, the study was subject to non-response or selection bias, which may mean that those most affected by injuries responded to the invitation to participate or that those affected by particularly serious injuries were unable to participate and, therefore, results may not be entirely generalizable to all rugby players. The inclusion of both elite and amateur level former rugby code athletes lends to increase the applicability of the study findings. Second, we acknowledge that the sample sizes may have been underpowered to detect some differences in reported injuries between groups for example, when comparing surgeries. Third, given the inclusion criteria for the study, a range of participant ages and sport exposure was expected. On average, participants had over 25 years in their sport, which suggests a large exposure for most participants. Injuries sustained during school sport were not within the scope of the current study. It is possible that former athletes in the non-contact sport group had taken part in rugby codes or other contact sports during their school years. Likewise, injuries sustained during other sports outside of rugby codes or the main sport of the non-contact athletes were not included in the study. Fourth, as with all studies involving an element of information recall, there is potential for recall bias, and so, there is a risk for underestimation or overestimation of injury occurrence. We took strategies to mitigate this risk by providing clear definitions of injuries, including concussion, and current conditions, such as medically diagnosed osteoarthritis. Finally, it was not possible to examine injury recovery time and time lost, and so, data cannot be directly compared with published reports of injury severity in terms of player-days absence and exact risk exposure. Nonetheless, our findings are consistent with prospective injury surveillance studies which report higher injury rates per 1000 player match-hours in rugby than in non-collision-based sports [1, 9].