與雙磷酸監類藥物相關的非典型股骨骨折

Bisphosphonate-Related Atypical Femoral Fractures

雙磷酸監藥物治療是骨質疏鬆症的常用藥物，在經過長期臨床使用後，逐漸出現顎骨壞死等數種併發症。第1例非典型股骨骨折在2005年發表於文獻後，這併發症才逐漸受到重視。形成的原因目前還沒有明確結論，推測和抑制破骨細胞（osteoclast）有關。美國骨礦質研究學會（American Society for Bone and Mineral Research, ASBMR）的第2次專案小組在2013年重新定義非典型股骨骨折，修改為5個主要表現中至少須符合4個，才是非典型股骨骨折，但次要表現則非必需。

Bisphosphonate is a common agent to treat osteoporosis nowadays. Several complications, including osteonecrosis of jaw bone, have been reported after the long-term use of bisphosphonate. After the first case report in 2005, atypical femur fractures nowadays have also been taken seriously. The exact cause of bisphosphonate-related atypical femoral fracture has not been established, and it is probably the result of suppression of osteoclast. Second report of a task force of the American Society for Bone and Mineral Research (ASBMR) in 2013 revised the definition of atypical femur fractures: at least four of five major features must be present, and none of the minor features is required. The concept of "drug holiday" was proposed to reduce incidence of atypical femur fractures after long-term use of bisphosphonate, and experts had made guidelines for period of bisphosphonate use. Surgical treatments of such patients with atypical fractures have increased complication rates, and some authors suggested prophylactic fixation for those who have non-displaced atypical fractures. Regarding the issue of delayed union or nonunion in atypical femoral fracture, some experts have used teriparatide or strontium ranelate to promote bone formation and fracture healing, but the effect is still controversial.