Effect of lumbar lordosis angle on the development of lumbar spondylolysis in adolescent baseball players: A cross-sectional study

Background

Lumbar spondylolysis (LS) is a lumbar vertebral arch stress fracture that often occurs in adolescent athletes, especially baseball players. An increase in lumbar lordosis angle (LLA) increases the compressive stress on the vertebral arch, influencing the development of LS. However, the effect of LLA on LS development in adolescent baseball players is unknown. Therefore, it is necessary to elucidate the risk factors that influence the development of LS. This cross-sectional study aimed investigate the effect of LLA on LS development in adolescent baseball players.

Methods

Patients were male baseball players aged 11–18 years who visited an orthopedic clinic with a chief complaint of lumbar pain and underwent a magnetic resonance imaging (MRI) examination between January 1, 2018, and October 31, 2021. LLA was defined as the angle formed by the line parallel to the superior endplate of the L1 and S1. A person other than the data analyst measured LLA three times from the MRI, and the average value was used for data analysis. Logistic regression analysis was performed, with the presence or absence of LS as the objective variable and LLA, age, and previous pitching experience as explanatory variables.

Results

Of the 112 subjects included, 79 were in the LS group and 33 in the non-LS group. The LLA was 45.42 ± 8.19° in the LS group and 36.68 ± 8.26° in the non-LS group, with significant differences between the groups. Logistic regression analysis showed that LLA significantly differed with an odds ratio of 1.140 (95% confidence interval: 1.070–1.21), even after adjusting for age and previous pitching experience.

Conclusions

LLA in adolescent baseball players was significantly greater in the LS group than in the non-LS group, which may influence the development of LS.