Posttraumatic osteoarthritis is primarily characterized by articular cartilage destruction secondary to trauma or fracture events. Even while intra-articular scar tissue can be observed following ankle fractures, little is known about its nature and molecular events linking its biological activity and cartilage deterioration. Here, we investigated scar tissue's histological and molecular characteristics, and its relationship with localized articular cartilage alterations consistent with early osteoarthritic degeneration. Intra-articular scar tissues from sixty-two patients who underwent open reduction internal fixation for ankle fracture were obtained at hardware removal time (6-44 months after fracture). Histological investigation using Hematoxylin-Eosin staining revealed that scar tissue contained fibrous hyperplasia with chondrometaplasia and overexpressed pro-inflammatory cytokines. Using quantitative Real-Time Polymerase Chain Reaction (qPCR) for molecular analysis, these fibrous scar tissues showed high messenger RNA (mRNA) expression levels of osteoarthritis-related markers (cytokines, chemokines, and enzymes) compared to the synovium. Furthermore, those transcriptional levels were significantly correlated with the grade of talar chondral damage. Our findings suggest that following an ankle fracture, the intra-articular fibrous scar tissue exhibits high catabolic and inflammatory activity, which has a long-lasting negative impact correlated to cartilage deterioration in the development of posttraumatic osteoarthritis.

Nhat Tien Tran completed his MD degree in 2015 at Hue University of Medicine and Pharmacy, Vietnam. After completing his orthopedic residency program, he moved to Korea and has worked as a Ph.D. candidate in medical science since 2020. He has also pursued a fellowship program at the Department of Orthopaedic Surgery, Jeonbuk National University Hospital, in South Korea. He concentrates on and performs research in foot and ankle surgery. Among some research topics that are still in progress, one article was published in SCIE. His investigation is related to posttraumatic ankle osteoarthritis (OA), which accounts for 80–90% of ankle OA. His findings provide novel information regarding posttraumatic OA pathophysiology and the molecular basis of human ankle posttraumatic osteoarthritis.