The study analyzes the burden of low back pain (LBP) in China, Japan, Thailand, and Pakistan from 1990–2021 and predicts trends to 2050 using age-standardized rates (ASRs). In 2021, Japan had the highest ASR, followed by China, Thailand and Pakistan. The number of cases peaked in productive age, ASR in middle and old age, with women having a higher burden than men. From 1990 to 2021, ASR decreased in China and Japan, increased in Thailand and Pakistan, but the number of cases increased in all countries. BAPC projections show ASR growth in Chinese men and Japanese women by 2050, decline in other groups. The decomposition analysis revealed the impact of ageing, population growth and epidemiological changes. LBP remains a major public health challenge, requiring tailored policies according to country, gender and age.