Fracture is uncommon cause of lymphedema. The mechanism of lymphedema progression is still unknown, but disruption of the lymphatic system during and after fracture might be involved. In contrast, breast cancer surgery is a common cause of lymphedema and is usually caused by the removal of axillary lymph nodes. Sentinel node biopsy (SNB) has been adopted in early breast cancer to reduce the risk of lymphedema. Thus, the incidence of lymphedema in SNB was lowered. However, less than 10% of SNB patients are still diagnosed with lymphedema, but it is known that it took years to diagnose. Recently, we encountered atypical lymphedema occurred after breast cancer surgery with SNB. Symptoms started earlier than usual and were more severe. Interestingly, she has a history of a proximal radial fracture on the same side of SNB. We thought there could be a relationship between the acceleration of breast cancer-related lymphedema and fracture