Determining the pathophysiological processes of frozen shoulder is a pivotal milestone in the development of novel treatment for patients with frozen shoulder. The goals of this CEU course are to review what is known to date about the biological pathophysiology of frozen shoulder, summarize the pathological changes associated with primary frozen shoulder, examine whether the right or dominant shoulder is more frequently affected, and explore whether treatment by intra-articular injections with corticosteroid and dissension is more effective than treating with corticosteroids alone or treatment-as-usual in a primary care setting.