Introduction

The Canada Games competition is the highest level of competition where amateur Canadian athletes can showcase their skills and talents during various events while competing against other athletes from other provinces or territories. These athletes must train for many years to qualify for the Canada Games, which may result in injuries that can be due to overtraining, inadequate nutrition, insufficient recovery, and poor technique.1,2 Previous studies have noted that injury history is considered one of the strongest predictors of future injury in athletes.3,4 For example, in Australian football players Orchard et al5 reported that previous injuries increased the risk of sustaining a muscle strain at the same location in the hamstrings, as well as in the quadriceps and calf muscles, using an observational cohort studying 5 high school sports over 3 years. Rauh et al6 found that previous injuries increased the risk of future injuries at the same location as the prior injury as well as to different regions. This relationship between injury history and future injury may be attributed to deficits in muscular strength, proprioception, altered movement patterns, reduced range of motion (ROM), and accumulation of scar tissue.2,7

Lower extremity injuries in an active, healthy adult population lead to intrinsic changes at the initial point of injury, which may contribute to increase risk of future injury.8 For example, having previous knee joint trauma has been associated with a two-to-three-fold increase in risk of future knee injury.9 Many recurrent injuries can be attributed to inadequate rehabilitation and premature return to play; however, some injuries may increase the risk of re-injury regardless of time interval between initial injury and future injury.7 Further, regional interdependence is an important factor of how movement occurring within the kinetic chain can contribute to future reinjury specifically to the lower extremity.10

The lower limb is the most common anatomical site injured among Olympic-level athletes with ankle and knee injuries reported most commonly amongst British and US athletes.11,12 Ankle injuries are said to be one of the most commonly reported injuries in sports, including soccer, basketball, football, and volleyball.13,14 Athletes who suffer an ankle injury can have symptoms such as mechanical instability, stiffness and swelling, and cartilage damage which can lead to degenerative changes.15 At the knee, anterior cruciate ligament injury (ACL) is the most common knee injury reported in athletes16; this injury can be detrimental to athletes because of post injury altered gait and knee kinematics, muscle weakness, and deficits in functional assessments, which are associated with long-term risk of meniscal tears, osteoarthritis, and chondral lesions.17–19 Further, the prevalence of patellofemoral joint injury is high and it mainly impacts athletes with no structural abnormalities.20 Rathleff et al21 reported that 25% of recreational athletes with patellofemoral joint injuries stopped participating in sports due to knee pain. Other lower extremity injuries such as those to the hip are also problematic in athletes as these have been associated with decline in athletic performance in various sports due to factors such as weaker hip adductor muscles, age, and ROM deficits.22 Multiple authors have noted that history of injury can increase risk of lower extremity joint injuries.1,2,23 However, the association between injury history and lower extremity joint injury is still unknown in the Canada Games.

Therefore, the purpose of this study was to examine the association between injury history and lower extremity joint injury during the Canada Games Competition between 2009-2019. The authors hypothesized that there would be a significant association between injury history and lower extremity joint injury across 10 years of Canada Games competition.

Methods

Study Design

This research study was a retrospective cohort design that assessed the association between injury history and incidence of lower extremity joint injury during the Canada Games competition between 2009-2019.

Participants

Seventeen thousand, one-hundred and one athletes competed in the Canada Games over 10 years of competition (8710 males and 8391 females). For the purposes of this study, the authors focused on lower extremity joint injury and examined reports of ankle, knee, hip, and patellofemoral injuries from a larger sample in which the descriptive epidemiology of Canada Games data were determined.24

Procedures

This secondary analysis of data was approved by the Brock University Ethics Board. Following approval, the Canada Games Council provided anonymized data for any athletes seeking medical attention during competition; athletes competing in the Canada Games gave consent for their data to be used for research purposes. All athletes provided the Canada Games with their medical history from an intake form that was provided to the athletes from the Canada Games Council; this medical history asked athletes to self-report if they previously experienced any of the following: concussion, major surgical procedures, neck and back injuries, trauma to joint or bone injuries and trauma to ligament or tendon injuries. The medical history, as well as injury data for athletes seeking medical attention, were provided to the researcher in a de-identified manner and included information such as, injury history, injury assessments, injury location and type of injury for each injury assessments.

Previous injuries (medical history) were then categorized and coded for concussion, major surgical procedures, neck or back injuries, trauma to joint and bone injuries and trauma to ligament or tendon injuries. For injuries incurred during the Canada Games competition, data were cleaned and coded in a descriptive epidemiological study,24 a further subset of this dataset was used for this current analysis based on injury location (ankle, knee, hip and patellofemoral joint) and injury type (fractures, sprains, meniscus, contusion, tendinopathy, arthritis, and patellofemoral pain syndrome). Additionally, information on athlete’s sex, province and sport were also provided. Data were inclusive of the Canada Games competition from 2009-2019.

Following categorization and coding of the data the total number of ankle, knee, hip, and patellofemoral joint injuries across 10 years of competition were determined using Microsoft Excel. Chi-Square test of Independence was performed to determine the association between injury history and lower extremity joint injury location and injury types. The statistical analysis was conducted using SPSS (IBM SPSS Version 26, Armonk, NY) and p < .05 indicated statistical significance.

Results

The initial data consisted of 17101 athletes (8710 male; 8391 females) who competed in the Canada Games competition between 2009-2019. From the sample 475 ankle injuries, 253 hip injuries, 503 knee injuries, and 106 patellofemoral injuries that were categorized as fractures, sprains, meniscus, contusion, tendinopathy, arthritis, and patellofemoral pain syndrome were identified during Canada Games competitions between 2009-2019. From 2009-2019 there were 125 fractures, 477 sprains, 68 meniscus, 133 contusions, 106 tendinopathy, 36 arthritis, or 96 patellofemoral pain syndromes were identified involving lower extremity joint injuries (Table 2). The relationship between reported cases of history of injury categories and injuries to the lower extremity joints are indicated in Table 1; while Table 2 demonstrates the relationship between history of injury categories and reported injury type.

Table 1.Results from 2x2 Contingency Table from Chi-Square analysis examining injury history and lower extremity joint injury.
Injury History Lower Extremity Joint Injury During Canada Games Competitions
Ankle Hip Knee Patellofemoral
Y N Y N Y N Y N
Head & Concussion Injuries Y 25 57 17 65 32 50 8 74
N 450 810 236 1024 471 789 98 1162
Major Surgical Procedure Y 23 61 18 66 33 51 10 74
N 452 806 235 1023 470 788 96 1162
Neck & Back Injuries Y 20 17 8 29 7 30 2 35
N 455 850 245 1060 496 809 104 1201
Trauma or overuse of
Joint & Bone
Y 73 139 43 169 68 144 27 185
N 402 728 210 920 435 695 79 1051
Trauma or Overuse of Ligament & Tendon Y 88 130 30 188 81 137 17 201
N 387 737 223 901 422 702 89 1035

*Y = Yes, N = No
*Y = Yes in both horizontal and vertical categories indicate having experienced both previous injury history on the vertical axis as well as experiencing an injury to the joint indicated on the horizontal axis, N = No in both the horizontal and vertical categories indicates not having experienced the previous injury on the vertical axis and the injury to the joint indicated on the horizontal axis. For example, in the upper left-hand box there were 25 participants who reported a history of a head and concussion injury and an ankle injury during competition, and there were 450 participants in the upper left hand box that did not report a history of a head and concussion injury; however, did experience an ankle injury.

Table 2.Results from 2x2 Contingency Table from Chi-Square analysis examining injury history and injury type.
Injury History Lower Extremity Joint Injuries During Canada Games Competition
Fracture Sprain Meniscus Contusion TP Arthritis PFPS
Y N Y N Y N Y N Y N Y N Y N
Head &
Concussion
Injury
Y 5 77 25 57 5 77 7 75 4 78 3 79 6 76
N 120 1140 452 808 63 1197 126 1134 102 1158 33 1227 90 1170
Major
Surgical Procedure
Y 6 78 23 61 9 75 8 76 9 75 1 83 9 75
N 119 1139 454 804 59 1199 125 1133 97 1161 35 1223 87 1171
Neck &
Back Injuries
Y 2 35 15 22 0 37 5 32 1 36 1 36 2 35
N 123 1182 462 843 68 1237 128 1177 105 1200 35 1270 94 1211
Trauma or Overuse of
Joint & Bone
Y 18 194 74 138 6 206 13 199 24 188 6 206 25 187
N 107 1023 403 727 62 1068 120 1010 82 1048 30 1100 71 1059
Trauma or Overuse of Ligament & Tendon Y 17 201 91 127 11 207 16 202 20 198 7 211 18 200
N 108 1016 386 738 57 1067 117 1007 86 1038 29 1095 78 1046

*Y= Yes, N = No,
*Yes, in both horizontal and vertical categories indicates having experienced both previous injury history on the vertical axis as well as experiencing injury type indicated on the horizontal axis, N = No in both the horizontal and vertical categories indicates not having experienced the previous injury on the vertical axis and injury type indicated on the horizontal axis. For example, in the upper left hand box, there were 5 participants who reported a history of a head and concussion injury and a fracture during competition, and there were 120 participants in the upper left hand box that did not report a history of a head and concussion injury; however, did experience a fracture during competition.
TP= Tendinopathy, PFPS= Patellofemoral Pain Syndrome

There was a significant association between history of neck and back injuries with ankle and knee injuries. There was also a significant association between history of trauma or overuse of ligament or tendon with hip injuries. History of trauma or overuse of joint or bone was significantly associated with patellofemoral joint injuries (Table 3). Ankle and knee injuries were six times more likely with prior neck and back injuries. Hip injuries were four times more likely with previous trauma or overuse of any ligament or tendon injuries and patellofemoral joint injuries were seven times more likely with previous trauma or overuse of joint or bone injuries (Table 3).

Table 3.Significant Association and Likelihood Ratio between injury history and lower extremity joint injury
Injury History Lower Extremity Joint Injuries During Canada Games Competition
Ankle Hip Knee Patellofemoral
Head & Concussion Injuries χ2 = 0.920
df = 1
p = 0.338
LR = 0.940
χ2 = 0.202
df = 1
p = 0.653
LR = 0.200
χ2 = 0.089
df = 1
p = 0.766
LR = 0.888
χ2 = 0.414
df = 1
p = 0.520
LR = 0.390
Major Surgical Procedure χ2 = 2.517
df = 1
p = 0.113
LR = 2.614
χ2 = 0.389
df = 1
p = 0.533
LR = 0.377
χ2 = 0.124
df = 1
p = 0.724
LR = 0.124
χ2 = 1.977
df = 1
p = 0.160
LR = 1.748
Neck & Back Injuries χ2 = 5.793
df = 1
p = 0.016
LR = 5.509
χ2 = 0.191
df = 1
p = 0.662
LR = 0.184
χ2 = 5.595
df = 1
p = 0.018
LR = 6.182
χ2 = 0.325
df = 1
p = 0.569
LR = 0.362
Trauma or Overuse of Joint & Bone χ2 = 0.102
df = 1
p = 0.750
LR = 0.102
χ2 = 0.337
df = 1
p = 0.562
LR = 0.337
χ2 = 3.140
df = 1
p = 0.076
LR = 3.140
χ2 = 8.158
df = 1
p = 0.004
LR = 7.164
Trauma or Overuse of Ligament & Tendons χ2 = 2.814
df = 1
p = 0.093
LR = 2.771
χ2 = 4.410
df = 1
p = 0.036
LR = 4.700
χ2 = 0.012
df = 1
p = 0.914
LR = 0.012
χ2 = 0.004
df = 1
p = 0.952
LR = 0.004

*Bolded = Statistically significant difference, LR = Likelihood Ratio

There was a significant association between history of major surgical procedures with meniscus injury. History of trauma or overuse of joint or bone injuries was significantly associated with contusion, tendinopathy, and patellofemoral pain syndrome. History of trauma or overuse of ligament or tendon was significantly associated with sprains (Table 4). Contusions were four and a half times more likely with a history of trauma or overuse of joint or bone injuries. Tendinopathy and patellofemoral pain syndrome were four and seven times more likely respectively, with trauma or overuse of any joint or bone injuries. Sprains were four times more likely with previous trauma or overuse of any tendon or ligament injuries (Table 4).

Table 4.Significant Association and Likelihood Ratio between injury history and injury type
Injury History Injury Type During Canada Games Competition
Fractures Sprain Meniscus Contusion TP Arthritis PFPS
Head Injuries & Concussion χ2 = 1.070
df =1
p = 0.301
LR = 1.196
χ2 = 0.975
df =1
p = 0.324
LR = 0.996
χ2 = 0.193
df =1
p = 0.661
LR = 0.182
χ2 = 0.185
df =1
p = 0.667
LR = 0.192
χ2 = 1.095
df =1
p = 0.295
LR = 1.245
χ2 = 0.319
df =1
p = 0.572
LR = 0.289
χ2 = 0.004
df =1
p = 0.953
LR = 0.003
Major Surgical Procedure χ2 = 0.500
df =1
p = 0.479
LR = 0.537
χ2 = 2.606
df =1
p = 0.106
LR = 2.708
χ2 = 5.914
df =1
p = 0.015
LR = 4.660
χ2 = 0.015
df =1
p = 0.902
LR = 0.015
χ2 = 0.977
df =1
p = 0.323
LR = 0.892
χ2 = 0.764
df =1
p = 0.382
LR = 0.948
χ2 = 1.711
df =1
p = 0.191
LR = 1.514
Neck & Back Injuries χ2 = 0.688
df =1
p = 0.407
LR = 0.796
χ2 = 0.415
df =1
p = 0.520
LR = 0.407
χ2 = 2.031
df =1
p = 0.154
LR = 3.903
χ2 = 0.553
df =1
p = 0.457
LR = 0.504
χ2 = 1.412
df =1
p = 0.235
LR = 1.845
χ2 = 0.000
df =1
p = 0.994
LR = 0.000
χ2 = 0.175
df =1
p = 0.676
LR = 0.190
Trauma or Overuse to Joint & Bone χ2 = 0.202
df =1
p = 0.653
LR = 0.207
χ2 = 0.045
df =1
p = 0.832
LR = 0.045
χ2 = 2.619
df =1
p = 0.106
LR = 3.010
χ2 = 4.026
df =1
p = 0.045
LR = 4.493
χ2 = 4.053
df =1
p = 0.044
LR = 3.697
χ2 = 0.021
df =1
p = 0.885
LR = 0.021
χ2 = 8.158
df =1
p = 0.004
LR = 7.164
Trauma or Overuse in Ligament & Tendons χ2 = 0.708
df =1
p = 0.400
LR = 0.739
χ2 = 4.366
df =1
p = 0.037
LR = 4.287
χ2 = 0.000
df =1
p = 0.988
LR = 0.000
χ2 = 1.927
df =1
p = 0.165
LR = 2.066
χ2 = 0.582
df =1
p = 0.445
LR = 0.561
χ2 = 0.278
df =1
p = 0.598
LR = 0.265
χ2 = 0.477
df =1
p = 0.490
LR = 0.460

* Bolded = Statistically significant difference, TP=Tendinopathy, PFPS=Patellofemoral Pain Syndrome,
LR = Likelihood Ratio

Discussion

The purpose of this study was to determine the association between injury history and lower extremity joint injuries during the Canada Games competition from 2009-2019. The key findings from this study were (1) previous injuries such as previous neck and back injuries, trauma or overuse of any ligament or tendon, and trauma or overuse of any joint or bone were associated with lower extremity joint injury and (2) any prior major surgical procedure, trauma or overuse of any ligament or tendon, and trauma or overuse of any joint or bone were associated with sprains, meniscus, contusion, tendinopathy, and patellofemoral pain syndrome. These findings are consistent with previous literature suggesting that injury history may increase the risk of future injuries.3,4,25,26 Multiple authors have suggested that re-injury can be attributed to neuromuscular factors that are present following initial injury.27,28 Following injury, alterations occurring in overall strength, proprioceptive abilities, and kinematics impact motor and cognitive function, which may be potential risk factors for re-injury. These factors may suggest areas for clinicians to target through rehabilitation strategies aimed to mitigate the risk of re-injury and/or new future injury.

Neck and back injuries were associated with ankle and knee injuries across 10 years of the Canada Games competition. These findings are similar to those reported in collegiate athletes as a history of lower back pain is a strong predictor of knee, ACL and other ligamentous injuries.29 The mechanisms behind this may include lower back pain resulting in alterations in trunk motor control, impaired postural control, delayed muscle latencies, and abnormal trunk muscle recruitment patterns.30,31 Further, there is an established association between previous neck and back injuries with lower extremity joint injuries in varsity-level athletes, which may be attributed to patients with lower back pain adopting a trunk-flexed posture and moving with greater knee extension.32 It is important to acknowledge that multiple authors have indicated a relationship between history of back injuries and hip rotation range of motion.33,34 However, no association was present in this current study. This may be due to the type of movement patterns involved in various sports that places different stresses on the joints of the lower extremity or it could be related to a self-report bias of injury history that may be present in this current study. To the authors’ knowledge, this study is the first to observe an association between previous neck injuries with ankle and knee injuries; however, because neck and back were grouped together it is possible that this association may be related to back injuries rather than neck injuries. Due to the retrospective nature of this study, the authors are unable to ascertain if previous injury history was related specifically to the neck or the back. Further investigation is needed to determine if there is a relationship between neck injuries and lower extremity joint injuries. If this relationship does exist, future research should consider the mechanisms that may contribute to the association between neck injuries and ankle and knee injuries.

Previous trauma or overuse to joint or bone was associated with patellofemoral joint injuries. Common risk factors for patellofemoral joint injury include training loads, movement technique, strength of lower extremity musculature, and type of footwear.35,36 There is a paucity of literature linking an association between previous joint or bone injuries with patellofemoral joint injuries. However, one study suggested a relationship between injury history and patellofemoral joint injuries as patellar dislocation or subluxation and surgeries have been noted to increase risk of future patellofemoral injuries.37 Previous authors have hypothesized that the mechanisms behind this association may be due to altered biomechanics, proprioceptive abilities, and neuromuscular control that may predispose an individual to future patellofemoral joint injuries.38–40 In addition, individuals with patellofemoral pain often demonstrate hip weakness, suggesting an association may exist between hip strength and patellofemoral joint injuries.41,42 Further investigation is needed to verify if altered biomechanics, proprioception, and neuromuscular control are the mechanisms for the association in this current study. Of note, one previous study indicated an association between major surgical procedures and patellofemoral joint injuries23; however, the current findings differ as there was no association between major surgical procedures and patellofemoral joint injuries. It is possible that variations in operational definitions between studies and/or a recall bias could have led to these differences. Additionally, foot abnormalities such as pes cavus are very common in athletes with patellofemoral joint injuries43; thus, it is possible that foot abnormalities may be one the factors behind the association between injury history and patellofemoral joint injuries. Other risk factors such as compressive instability, patellar trauma, soft tissue lesions, overuse syndromes, and osteochondritis may increase the risk of a patellofemoral joint injury suggesting an association with previous trauma or overuse of joint and bone injury.38

In this study, previous trauma or overuse of any ligament or tendon was associated with hip injuries. This is consistent with previous reports indicating that there is an association between injury history and hip injuries.39 One study reported weakness in the hip abductor muscles in individuals with a history of ankle sprains this may suggest that weakness in hip stabilizing musculature resulting in joint deviations and decreased hip stability, was related to proximal kinetic chain maladaptation resulting from ankle ligamentous instability.44 After lower limb ligamentous injuries, dynamic postural stability of the lumbopelvic complex decreases, which can increase the risk of hip injuries.45 Athletes with prior ligamentous injury may experience sensory and motor behavior deficits, which have been attributed to the lack of connection between mechanoreceptors and nervous system restoration.10 For example, deficits in knee joint position sense during passive and action range of motion have been observed with athletes with ACL injuries.4 Researchers have speculated that decrease in hip musculature can contribute to faulty lower extremity mechanics during dynamic tasks.

The current findings of association between previous trauma or overuse of ligament or tendon injury and sprains are consistent with conclusions of multiple authors indicating that previous injuries were the most important risk factors for sprains.46–48 For example, Bahr & Bahr49 reported that there is a six-to-ten-fold increase in future ankle sprains with prior history of ankle injuries. Multiple authors have hypothesized the increase in future ankle sprains may be due to the mechanical (persistent ligamentous laxity) and functional (proprioceptive deficits) instability of the joint.25,50 To the authors’ knowledge, this is the first study to report an association between previous major surgical procedures and contusions; however, the potential mechanisms involved in this association is currently unknown. Thereby, further investigation is required to determine the potential mechanism involved.

This current study did not focus on the differences in the association of injury history and lower extremity joint injury between male and female athletes so the authors are unable to ascertain if biological sex may have been a factor in injury risk. Further, self-reported injury history was utilized in this study, and although this is a commonly accepted practice, it results in potential recall bias of athletes underestimating or overestimating their injury history. Previous literature has suggested that athletes neglect reporting symptoms of concussion to medical personnel which means that it is likely that history of concussions may be under reported.51,52 LaBotz et al52 reported 48% of collegiate athletes reported signs and symptoms of concussions using the Concussion Symptom Survey Design (CSS), but only 17% reported symptoms of concussions using the Pre-Participation Physical Exam (PPE). It is possible that an underreporting of concussion history during the medial history intake in this study led to the lack of association between concussion history and lower extremity joint injury in the Canada Games athletes included in this study. Internal risk factors, such as an athlete’s psychological disposition are poised to modify injury risk.53,54 Further, Renton et al55 reported a positive association between athlete identity (eg, depressive symptoms, performance traits, self-worth, motivation) and behaviour (eg, adherence and playing through pain) with injury-related outcomes. Additionally, risk-taking behavior and various psychological factors may be important to consider, especially for athletes who are repeatedly injured.56 While this current study did not obtain information on athletes’ psychological disposition it may be advantageous for researchers to consider these factors in future association studies. While this is the first study to look at the association between self-reported injury history and injury occurrence in athletes participating in the Canada Games competition these findings lack external validity as they cannot be generalized to the general population. Further, due to the de-identified dataset, the authors are not able to ascertain the number of participants who had competed in the Canada Games more than once. Finally, in this study, information regarding injury history was limited to the categorization of previous injuries based on Canada Games medical history intake forms; thus, the criteria that were used for gathering injury history data were non-modifiable. However, this is the only study to specifically assess the association of prior injuries with future injuries incurred in the lower extremity joints, and this is the first study to examine the association between injury history and lower extremity joint injury in the Canada Games.

Conclusion

The results of the current study confirm the hypothesis that injury history is associated with lower extremity joint injury across 10 years of Canada Games competitions. Association between history of neck and back injuries with ankle and knee injuries, history of trauma or overuse of ligament or tendon and hip injuries and history of trauma or overuse of joint or bone and patellofemoral joint injuries were all noted.


Acknowledgements

Thank you to the Canada Games Council for providing de-identified data for this study. This study was supported by a Brock University Match of Minds Grant and Brock University Canada Games Grant. Nicole Chimera is supported in part by funding from the Social Sciences and Humanities Research Council.

Conflict of Interest

The authors have no additional conflicts of interest related to this study to disclose.