National and regional trend over time in the prevalence of osteonecrosis of the femoral head among military draft-eligible males in South Korea: an analysis of a nationwide database from 2013 to 2022.

Purpose: To evaluate the prevalence of ONFH among the military draft-eligible male population in South Korea between 2013 and 2022.

Methods: A total of 3,166,669 individuals were examined at regional Military Manpower Administration offices for 10 years. In a study using a retrospective analysis of prospectively collected data, the prevalence of ONFH per 100,000 individuals, along with the 95% confidence interval (CI), was measured among military draft-eligible Korean males. The Mann-Kendall trend test was performed to assess the correlation of the ONFH prevalence with several potentially related factors.

Results: The mean annual prevalence of ONFH was 13.04 (95% CI: 9.06-17.01), indicating a rare entity. The prevalence was nearly consistent (Tau = - 0.2; p = 0.484), with the highest in 2018 (21.54; 95% CI: 16.42-26.66) and the lowest in 2020 (10.99; 95% CI: 7.12-14.85). Unilateral ONFH had a higher proportion than bilateral ONFH. There was a significant correlation between the prevalence of ONFH and the rate of risk alcohol consumption (Tau = 0.644, p = 0.009).

Conclusion: The prevalence of ONFH in military draft-eligible males was low, with nearly consistent trends between 2013 and 2022. Unilateral ONFH was relatively high compared to bilateral cases, highlighting distinctive characteristics in the military draft-eligible male population.