Prevalence of spondylolisthesis in a population of gymnasts.

Spondylolysis occurs in 6 % of the general population. Of these, approximately 75% will develop spondylolisthesis. According to multiple studies, an increased prevalence of spondylolysis and spondylolisthesis exists in groups of athletes practicing certain sports such as gymnastics. In the literature, prevalence of spondylolisthesis in gymnasts can reach up to 40 to 50 %. However, the specific risk factors associated with the development of spondylolisthesis in gymnasts are not known. The main purpose of this study was to evaluate the prevalence of spondylolysis and spondylolisthesis in a population of gymnasts, as well as the associated epidemiological characteristics. In order to achieve this goal, we presented our project to the two most renowned gymnastics centers in the city of Montreal, which allowed us to recruit a total of 93 gymnasts (19 males and 74 females). A radiological evaluation, with the low emission radiographic system, EOS, allowed us to identify the subjects that were affected by spondylolysis and spondylolisthesis. Additionally, standardized questionnaires allowed us to evaluate and compare different epidemiologic parameters such as age, height, weight, number of years of practice, number of hours of training per week. Of the 93 gymnasts evaluated clinically and radiographically, we identified 6 (1 male, 5 females) gymnasts presenting a spondylolysis and/or spondylolisthesis. This 6.5% prevalence found in our population is similar to the one reported in the general population. Gender did not seem to be a determinant factor. Also, gymnasts with and without spondylolysis and/or spondylolisthesis seemed to be similar in terms of height. However, gymnasts with spondylolysis and/or spondylolisthesis seemed to be heavier than gymnasts without one of these two affections, older and training with greater intensity. These results suggest that the real prevalence rate of spondylolysis and spondylolisthesis in gymnasts may have been overestimated in previous studies. A selection bias, due to the high competitive level in the two gymnastics centers where our recruitment took place, could be involved. Our findings could also be the result of new or different training methods compared to those used in past studies. This might suggest that with intense training schedules, heavier individuals could potentially be prone to increased loads at the lumbosacral junction, thus favoring the development of spondylolysis and spondylolisthesis. These hypotheses should be explored in further details in the near future, especially with investigation of radiological parameters of the spine and pelvis.