Global, regional, and national burden of low back pain, 1990-2020, its attributable risk factors, and projections to 2050: a systematic analysis of the Global Burden of Disease Study 2021 - Ferreira, Manuela L.; Bärnighausen, Till; Jonas, Jost B.; Panda-Jonas, Songhomitra (The lancet. Rheumatology, 2023)