Grady Mary K, Watson J Tracy, Cannada Lisa K
Department of Orthopaedic Surgery, Saint Louis University, St Louis, Missouri 63110, USA.
Orthopedics. 2012 Jun;35(6):e991-5. doi: 10.3928/01477447-20120525-51.
Bisphosphonates are a class of drugs that prevent bone loss by decreasing bone resorption. They represent a major treatment for osteoporosis and other metabolic bone diseases. Recent reports suggest that a potential complication of long-term bisphosphonate therapy may be atypical insufficiency fractures of the femur. Concern exists about delayed union after fracture stabilization in patients taking bisphosphonates.This article describes 2 patients on long-term bisphosphonate therapy treated for atypical femur fractures that failed to heal with intramedullary nailing. Both patients' fractures occurred after at least 4.5 years of bisphosphonate use and displayed classic findings of bisphosphonate fractures reported in the literature, including a subtrochanteric location, presentation after minimal trauma, transverse fracture, no comminution, and cortical beaking. The original fractures were treated at other institutions with intramedullary nails. Subsequently, both patients presented with pain and atrophic nonunion of their fractures. Evaluation included a computed tomography scan of the fracture and a metabolic workup. The patients discontinued bisphosphonate therapy. They were treated with nail removal and definitive plating to achieve compression across the fracture site. Both fractures went on to heal after this treatment with no further complications.The literature currently recommends treating bisphosphonate fractures with an intramedullary nail. Perhaps initial treatment of these fractures should be similar to an atrophic nonunion, involving compression plating to obtain bone-on-bone contact and promote healing. This would address the biologic and mechanical etiologies of the bisphosphonate fracture.
双膦酸盐是一类通过减少骨吸收来预防骨质流失的药物。它们是骨质疏松症和其他代谢性骨病的主要治疗药物。最近的报告表明，长期双膦酸盐治疗的一个潜在并发症可能是股骨非典型性不全骨折。服用双膦酸盐的患者骨折固定后存在愈合延迟的担忧。本文描述了2例接受长期双膦酸盐治疗的患者，他们因非典型股骨骨折接受髓内钉治疗但未愈合。两名患者的骨折均在使用双膦酸盐至少4.5年后发生，并表现出文献中报道的双膦酸盐骨折的典型特征，包括转子下部位、轻微创伤后出现、横行骨折、无粉碎以及皮质骨断裂。最初的骨折在其他机构接受了髓内钉治疗。随后，两名患者均出现骨折部位疼痛和萎缩性骨不连。评估包括骨折部位的计算机断层扫描和代谢检查。患者停止了双膦酸盐治疗。他们接受了取出髓内钉并进行确定性钢板固定治疗，以实现骨折部位的加压。经过这种治疗，两处骨折均愈合，无进一步并发症。目前文献推荐用髓内钉治疗双膦酸盐骨折。也许这些骨折的初始治疗应类似于萎缩性骨不连，采用加压钢板固定以获得骨对骨接触并促进愈合。这将解决双膦酸盐骨折的生物学和力学病因。
