MED5218 Sports Injuries – Scientific Basis of Prevention and Rehabilitation

MSc Sport and Exercise Science

Critical Evaluation of Lysholm and Wiklander’s “Injuries in Runners” (1987)

Iain Christie 1107897

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James et al. (1978) state that “runners comprise a very healthy segment of our population that most likely would not have any difficulty performing almost any other type of athletic endeavour except the one they have chosen”, a proclamation that highlights the severity associated with injuries to long distance runners as well as how regularly they occur. Extensive investigation has been carried out to determine the common site of injury caused by this activity, as well as the mechanisms involved in such injuries. It is the aim of this evaluation to critique one such paper, with detailed analysis of the relevance of the study, experimental methods used, and overall results and conclusions drawn. The paper that was critiqued was “Injuries in runners” by Lysholm and Wiklander (1987).

Before such a review can be approached, an understanding must first be gained of the evidence presented by other literature relating to injuries encountered from endurance running. Regarding the common locations of injury, Van Gent et al. (2007) found that 19.4% to 79.3% of injuries occurred in the lower extremities, with the knee in particular being the most predominant site of injury (7.2% to 50.0%). This was in accordance with the general opinion of other studies focusing on endurance running injuries (Maughan and Miller (1983); Taunton et al. (2003); Buist et al. (2010)).

This evidence was used as a point of reference for comparison to Lysholm and Wiklander (1987) to help gain a clear and balanced overview of the relevance and reliability of the study. It could be argued that the title of the article is rather vague, as it does not narrow down into the exact type of running that is being investigated. However since the population of the study includes three groups of runners (the sprint group, the middle distance group, and the long distance and marathon group) the title “Injuries in runners” does indeed suffice. The abstract accurately describes the population involved in the investigation. However there is little information about what the experimental method actually consisted of. It does state that both groups of runners were carefully monitored over a year’s training, but it may also have been useful to clarify whether this training program was applied for the purpose of the study, or if the athletes continued with a pre-existing regime. The abstract also offers an adequate summary of general findings, including common sites of injury for all groups, as well as a sentence alluding to how a combination of factors could have led to the injuries. It is important to note that in regards to injury location for marathon runners, the findings highlighted in the abstract are contrary to the general consensus of other studies. It is widely documented (Stergiou et al. (1999) and BenGal et al. (1997)) that the most common injury site for long distance runners is the knee, whereas it is suggested in this study that it is foot problems that were most common. Due to the large volume of literature that back up the suggestion of the knee being the most common injury site questions must be raised over the reliability of Lysholm and Wiklander’s findings, however no conclusions can be drawn based purely on the abstract.

In the opening sentences of the introduction, the authors make statements regarding the types of injuries that commonly occur with runners, declaring that “injuries in runners are almost exclusively exertion injuries” and “apart from ankle sprains, trauma is rare”. However no references are offered here to strengthen these points. They then go on to highlight how running injuries differ from those acquired through soccer. It is unclear what the relevance of

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this comparison is, as no practical implications are mentioned, and rather it seems relatively obvious that knowledge on soccer injuries should not be applied to running due to the difference in nature of the sports. The introduction is slightly sparse in terms of current evidence on running injuries, and it seems that a greater justification for the study could be shown by exploiting any gaps in this evidence, making way for a unique study. This is an aspect which cannot be seen in the introduction. However, the last paragraph of the introduction does state, in a relatively concise manner, the purpose of the investigation, which was to “calculate the incidence of injury in relation to training exposure, to study injury-provoking factors in training and competition, and to compare differences in injury pattern between different groups of runners”. Again though, more detail would have been useful, particularly in regards to how the findings of such a study could be used in a practical environment in terms of either injury prevention or rehabilitation.

For the experimental method, a large population group is used (60 runners; 44 male and 16 female), which will increase the accuracy and reliability of the study. The reader is also given information on the runners’ ability levels, median experience (in years) and age. There is a significant difference of average age for the long distance/marathon runners, compared with the other two groups. Since one of the main points of focus of this study is to compare the differences in injury patterns between different groups of runners, it is unclear whether these variations may be affected by age differences, as opposed to the different types of activity being performed. As mentioned when interpreting the abstract, there is a slight lack of detail about the training that the groups of runners are completing. The authors inform the reader that the runners “recorded in detail their training and competition, month for month, over a period of one year, and their reports were analysed” and it is to be assumed that this training was the same as the program that the runners had been performing prior to the trial, as opposed to adopting a regime implemented for the purpose of the study. However more clarity on this point would have been useful. On a positive note, the authors clearly define what they would class as an injury for the study, stating that “any injuries that markedly hampered training or competition for at least one week were noted”. In general, an important aspect of experimental methods for any type of study is that the trials could be replicated, and due to lack of information on the types of training exercises being carried out for the duration of this trial I feel that this is not the case here. One of the main research questions as suggested in the introduction was “to study injury-provoking factors in training and competition” and it seems only rational that some detail on what the training involved would be necessary to draw valid conclusions on this point.

In relation to this point, the opening paragraph of the results section offers some information on training in terms of average duration of sessions, how often these were being completed, and whether the groups’ programmes involved sprints, endurance, strength, technique or flexibility exercise. The detail given here is still rather vague though, and it would have been more valuable to have this paragraph in the methods section. The results then go on to provide evidence for how often injuries occurred for each group as well as their location. Tables are offered that present this information. It could be argued that this data may be unreliable due to differences in what could be classed as an injury. As previously

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highlighted, injuries were defined as afflictions that hampered training for at least a week. However there is an element of participant discretion involved in diagnosis of injury. For example one runner could continue training with an injury that they feel is bearable, whereas the same injury could provoke another participant to take time out of training to recover. This variable may have been a factor in why findings of injury location in this study differ from other literature.

Throughout the discussion section there is reference to papers focusing on soccer players. As with the introduction, it is unclear what the relevance of this comparison is. The main point that is suggested in the discussion is the interplay between extrinsic and intrinsic factors. This is a valid assumption based on the evidence presented in the results section; however there is very little detail as to what these factors actually are. The authors use a figure to display this combination of some of these factors, showing how training error, surface/shoes and malalignment interact. This is the first time these concepts are introduced in this study, and there is little mention of them in the discussion section out with this figure. It would have been valuable to give greater emphasis to the significance of malalignment in the study of running injuries as this is a topic that has received a substantial amount of focus by other literature. Johnston et al. (2003) suggest malalignment as a strong factor in determining the risk of injury. This idea is also studied by Wen et al. (1998) who actually criticise the Lysholm and Wiklander study. They comment on the lack of clarity over how the study in question determined malalignment, and also reference how no control group was used.

The discussion looks at injuries experienced by the long distance/marathon group in particular. The authors write that “a significant relation emerged between the injury rate during a given month and the distance covered during the preceding month” which is an accurate point to make based on the findings of the study. However there is no mention of any mechanisms of such injuries. This is also lacking when they highlight the differences in injury patterns between groups. There is no detailed explanation of why these differences occurred. In the closing sentence of the discussion the authors acknowledge how their findings regarding injury site differs from other papers, however they offer no hypothesis as to why this happened.

The study concludes with emphasis on training errors and malalignment, but fails to focus on the relevance and importance of this in a practical environment. For example, it would have been valid to mention how such findings could prove to be useful in injury prevention or rehabilitation. Although it closes with saying further study would be required in the future into intrinsic factors, there is no real “take home message” in the conclusion. They state that malalignment was involved in a high percentage of the cases, and so it would make sense to discuss how to approach this point in injury prevention, and perhaps suggest this as a topic in which further research is required.

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References

Buist, I., Bredeweg, S.W., Bessem, B., van Mechelen, W., Lemmink, K.A.P.M, Diercks, R.L. (2007). Incidence and risk factors of running-related injuries during preparation for a 4-mile recreational running event. British Journal of Sports Medicine. 44: 598-604

James, S.L., Bates, B.T., Ostering, L.R. (1978). Injuries to runners. American Orthopaedic Society for Sports Medicine. 6(2)

Johnston, C.A.M., Taunton, J.E., Lloyd-Smith, D.R., McKenzie, D.C. (2003) Practical approach for family doctors. Candian Family Physician. 49: 1101-1109

Lysholm, J. and Wiklander, J. (1987). Injuries in runners. The American Journal of Sports Medicine. 15(2)

Maughan, R.J. and Miller, J.D.B. (1983). Incidence of training-related injuries among marathon runners. British Journal of Sports Medicine. 17(3): 162-165

Taunton, J.E., Ryan, M.B., Clement, D.B., Mckenzie, D.C., Lloyd-Smith, D.R., Zumbo, B.D. (2003). A prospective study of running injuries: the Vancouver Sun Run “In Training” clinics. British Journal of Sports Medicine. 37: 239-244

Van Gent, R.N., Siem, D., Van Middelkoop, M., Van Os, A.G., Bierma-Zeinstra, S.M.A., Koes, B.W. (2007). Incidence and determinants of lower extremity running injuries in long distance runners: a systematic review. British Journal of Sports Medicine. 41: 469-480

Wen, D.Y., Puffer, J.C., Schmalzried T.P. (1998). Injuries in runners: A prospective study of alignment. Clinical Journal of Sport Medicine. 8: 187-194

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