Clinical presentation and pathological features of atypical subtrochanteric fracture after bisphosphonate treatment

In recent years, there have been increasing reports of fractures associated with long-term bisphosphonate treatment. Clinical presentation should be examined carefully because fractures after long-term bisphosphonate treatment present typical symptoms and radiological and pathological findings. The unique clinical features of such fractures include prodromal thigh pain and complete absence of trauma. The radiological features include stress reaction of the thickened cortex and transverse or short oblique fractures on plain-film radiography and bone marrow edema on magnetic resonance imaging. Careful surveillance and early preventive internal surgical fixation must be considered by both orthopedic and non-orthopedic physicians. In this study, we reviewed recent articles on atypical subtrochanteric fractures after long-term bisphosphonate treatment. We also present the case of a 72-year-old woman with this type of a fracture who had been using a bisphosphonate for 2 years. The findings at presentation and pathological features of the fracture are discussed, including those of imaging studies, and the treatment administered is described.