A 35-year-old woman had spent two years with a worsening left knee. It hurt, it swelled, it clicked, and it sometimes locked. When doctors looked at her MRI, they saw something that reminded them of a popular drink: many round, uniform nodules suspended in fluid, like tapioca pearls in bubble tea.
Orthopedic surgeons at the All India Institute of Medical Sciences in Raipur described the case in the Journal of Orthopaedic Case Reports in August 2026 and proposed a name for the appearance: the "Boba Tea Sign." The cause was synovial chondromatosis, an uncommon condition in which the joint lining produces pieces of cartilage that can break loose inside the joint.
