A Systematic Review of the Histological and Molecular Changes in the Subacromial Bursa in Rotator Cuff Disease

To evaluate the involvement of the subacromial bursa in the pathologic development of rotator cuff disease (RCD), a systematic review of the literature was undertaken to assess the cellular, biochemical and metabolic changes in the bursa. A systematic review was performed to identify all studies that reported histological and molecular changes in the subacromial bursa pertaining to RCD. The molecular biomarkers found to be altered in RCD included extracellular matrix enzymes, cytokines, growth factors and neuronal signals. Previous reports show an increase in IL-1, IL-6, TNFα, bone morphogenic proteins, substance P and vascular endothelial growth factor. All of these factors may contribute to the etiology and pathological changes in rotator cuff disease, but further study is needed to determine the specific role of the subacromial bursa in the pathophysiology of RCD. (Journal of Surgical Orthopaedic Advances 29(1):1-4, 2020) Key words: rotator cuff disease (RCD), bursitis, subacromial bursa, shoulder impingement, interleukins, COX enzyme, bone morphogenic proteins (BMPs), substance P, vascular endothelial growth factor (VEGF), biologic drugs, anti-metabolites