Pathogenic involvement of joints and other synovium-lined structures, including tendon sheaths and bursae, is a relatively uncommon but important form of infection. Its significance is related to the severe destruction of musculoskeletal structures it can cause, which often results in…
Introduction The synovium is one of the more recent phylogenetic developments of the vertebrate locomotor system, with the first synovial joints appearing in the piscine jaw of ancestors of the modern lungfish. Embryologically, the synovium is derived from specialized mesoderm…
The group of so-called fibrohistiocytic tumors encompasses those tumors that were formerly believed to show evidence of hybrid fibroblastic and histiocytic differentiation. In truth, the neoplastic cells in these lesions likely represent either modified fibroblasts/myofibroblasts, or cells of histiocytic lineage,…
Introduction Tumors with myofibroblastic and fibroblastic differentiation comprise an ever-expanding and diverse group of largely spindle cell neoplasms. Some are characterized by recurrent gene fusions, resulting in chimeric transcription factors that initiate proliferative programs driving tumorigenesis and fibrous phenotype, while…