The aim of this study was to evaluate the longitudinal changes of trabecular bone score (TBS) during and after bisphosphonate (BP) treatment in postmenopausal Korean women with osteoporosis.

We analyzed 191 patients who took BP and underwent bone mineral density (BMD) test for the period from January 2010 to December 2015. The mean follow up period during treatment and after treatment was 22.8 months and 18 months, respectively. The TBS and BMD values were evaluated by the percent changes relative to the baseline.

In 191 patients, who treated with BPs, L-spine BMD increased 3.65±0.5% and TBS increased 0.26±0.4% from baseline during first 1 year. At 2 to 4 years, the changes of BMD and TBS from baseline gradually increased up to 9.3±3.25% and 2.69±0.98% and both results showed statistically significant correlation. In 86 patients who stopped BPs, L-spine BMD decreased -0.54±1.07% and TBS increased 0.33±1.96% from baseline during 3 years follow up period.

Lumbar spine TBS increase over time with BPs treatment although the changes were less than that of BMD. Also, it preserve for years after stopping treatment, as the changes of lumbar spine BMD. The results of BMD and TBS showed significant correlation during treatment but not during drug withdrawal.