RESUMO
Background: Lumbar disk degeneration (LDD) occurs frequently in athletes. Researchers have found that LDD occurs mainly in the lower disks (L4/L5 and L5/S1) in the general and athletic populations. However, a retrospective study showed a high prevalence of LDD in the upper lumbar disks (L1/L2), especially in elite gymnasts. Purpose: To investigate the effect of competition level on the prevalence and incidence of LDD in the upper lumbar disks (L1/L2). Study Design: Cross-sectional study; Level of evidence, 3; and cohort study; Level of evidence, 2. Methods: We conducted 2 studies to evaluate the effect of competition level on the prevalence and incidence of LDD in Japanese collegiate gymnasts. In study 1, a cross-sectional study of 298 collegiate gymnasts was conducted between 2011 and 2015. Competition levels were categorized as regional, national, and international, and T2-weighted magnetic resonance imaging (MRI) was used to evaluate LDD. Chi-square testing was applied to assess differences in the prevalence of LDD and spinal levels among the 3 competition levels. In study 2--a prospective cohort study--LDD progression and its related risk factors were investigated in 51 collegiate gymnasts. Baseline lumbar MRI scans and measurements of physical function (generalized joint laxity and finger-floor distance test) were performed in March 2014. Follow-up lumbar MRI scans were obtained 2 years later, in February 2016. Logistic regression analyses were performed to investigate the relationship between competition level and LDD progression. Results: In study 1, the prevalence of at least 1 degenerated disk in the regional, national, and international groups was 44.2% (19/43), 44.7% (98/219), and 52.8% (19/36), respectively (P = .655). The prevalence of LDD at L1/L2 in the international group was significantly higher than that in the other 2 groups (P = .018). In study 2, the presence of LDD at L1/L2 was associated significantly with international-level competition (adjusted odds ratio, 47.8; 95% CI, 2.75-830.50). Conclusion: In Japanese collegiate gymnasts, competing at the international level was found to be a risk factor for LDD at L1/L2.
RESUMO
BACKGROUND: Magnetic resonance imaging (MRI) studies have shown that gymnasts have a high prevalence of radiological abnormalities, such as intervertebral disk degeneration (IDD) and anterior limbus vertebra (ALV). These 2 abnormalities may coexist at the same spinal level. However, the relationship between IDD and ALV remains unclear. HYPOTHESIS: A significant relationship exists between IDD and ALV in Japanese collegiate gymnasts. STUDY DESIGN: Case-control study. METHODS: A total of 104 Japanese collegiate gymnasts (70 men and 34 women; age, 19.7 ± 1.0 years) with 11.8 ± 3.6 years of sporting experience participated. T1- and T2-weighted MRIs were used to evaluate ALV and IDD. RESULTS: The prevalence among the gymnasts of IDD and ALV was 40.4% (42/104) and 20.2% (21/104), respectively. The prevalence of IDD was significantly higher in gymnasts with ALV than those without ALV, as determined using the chi-square test. Logistic regression analysis demonstrated a significant association between IDD and ALV (adjusted odds ratio [OR], 6.60; 95% confidence interval [CI], 2.14-20.35). IDD was further grouped by whether it was present in the upper lumbar region (L1-2, L2-3, and L3-4 disks) or in the lower lumbar region (L4-5 and L5-S1 disks). Upper IDD had a greater association with ALV (adjusted OR, 33.17; 95% CI, 7.09-155.25) than did lower IDD (adjusted OR, 6.71; 95% CI, 1.57-28.73). CONCLUSION: In Japanese collegiate gymnasts, ALV is a predictor of IDD, especially in the upper lumbar region. CLINICAL RELEVANCE: Information regarding ALV is important to prevent IDD in Japanese collegiate gymnasts.
