Periprosthetic humeral shaft fractures are increasing in incidence as shoulder replacements become more common. Surgical management of humeral shaft fractures can only be deemed appropriate when the degree of pain, the extent of disability, and the number of comorbid conditions are taken into consideration. Among trauma surgeons there exists no preferred surgical approach to fractures of different segments of the humerus; however, the anterolateral approach to midshaft fractures is the most common although viable alternative approaches exist. In this case, we perform an open reduction and internal fixation of a diaphyseal periprosthetic humeral fracture with a posterior triceps sparing approach.