A Case Report of Bisphosphonate-induced Bilateral Osteoporotic Subtrochanteric Fracture Femurii: Review of Literature.

INTRODUCTION: Osteoporosis is a significant health-care problem characterized by excessive skeletal fragility, susceptibility to low-trauma fractures in men as well as women. Any abnormality of the bone that reduces the strength of the bone predisposes it to mechanical failure during normal activity or with minimum trauma. The mechanical failure manifests itself as a fracture, and this fracture must be recognized as a pathological fracture if the patient is to be treated properly. Osteoporosis is one of the leading causes of such pathological fractures and accounts for 1.5 million fractures annually. In the following case report, we present a 56-year-old postmenopausal female patient with bilateral pathological subtrochanteric fracture femurii due to intake of bisphosponates for 4 years for osteoporosis. Bilateral pathological subtrochanteric femurii fractures are extremely uncommon injuries which occur in adults who sustain injuries due to trivial trauma. A variety of management modalities has been tried to treat this complex fracture pattern. Standard fixation treatment is intramedullary nailing.

CASE REPORT: A postmenopausal female of rheumatoid arthritis aged 56 years, presented to our emergency department with a history of trivial fall at home. Following the fall, she was unable to bear weight on bilateral feet and complained of deformity. History revealed consumption of bisphosphonates (tablet alendronate 10 mg) for the last 4 years and glucocorticoids for rheumatiod arthritis. Radiographs were taken, which revealed bilateral pathological subtrochanteric fracture femurii. After obtaining necessary fitness, the patient was taken up for surgery. Closed reduction and Internal fixation with long proximal femoral nail were done. Bisphosphonate intake was stopped and teriparatide 20 µg/day subcutaneously given for 3 months. Fracture healed after 3 months and patient resumed her daily activities.

CONCLUSION: In people taking long-term bisphoshponate therapy, symptomatic cortical stress reactions accompanied by evidence of a stress line across the cortical thickening suggest an increased risk of a complete stress fracture. The patients should be informed about the prodromal symptoms like pain and swelling, following this bisphosphonates should be stopped and teriparatide has to be started for osteoporosis.