Stress fracture of the ulna associated with bisphosphonate therapy and use of walking aid.

We report a case of a stress fracture of the ulna secondary to long-term bisphosphonate therapy and walking cane. Physicians need to have a high index of suspicion of stress fractures occurring in patients complaining of chronic upper limb pain if they are on bisphosphonate therapy and are using walking aids. Stress fractures of the upper extremities are rare and are usually associated with athletes; however, a few recent case reports have shown an association between stress fractures of the upper extremities and the use of walking aids. The association between increased incidence of upper extremity stress fractures and the use of both bisphosphonates and walking aids in patients has not been well studied, with only one previously reported case. Here, we report a case of a complete stress fracture of the ulna in a 77-year-old female, premorbidly ambulant with walking cane, on long-term bisphosphonates without any pre-existing medical conditions which could result in secondary causes of bone loss. Investigations did not reveal any causes of pathological fracture. This fracture is attributed to the use of long-term bisphosphonate therapy in conjunction with the use of a walking cane. This case highlights the importance of entertaining the possibility of such fractures occurring in any patient who is on bisphosphonate therapy presenting with stress fractures of the upper extremity.