title: Atypical femoral fractures during prolonged use of bisphosphonates: short-term responses to strontium ranelate and teriparatide.
abstract: BACKGROUND
  Atypical femoral fractures have rarely been reported in women taking bisphosphonates, but this is still a controversial issue. Data are derived mainly from observation studies because a post hoc analysis from a randomized clinical trial did not find any such association.
  
  
  OBJECTIVE
  The aim of this study was to report three cases of what are considered atypical femoral fractures and their responses to the use of strontium ranelate and teriparatide.
  
  
  METHODS
  We studied three postmenopausal women with a diagnosis of osteoporosis who suffered fractures of the subtrochanteric region and femoral diaphysis with no major trauma while on long-term use of bisphosphonates.
  
  
  RESULTS
  All the major features of atypical femoral fractures highlighted in the Task Force Report of the American Society for Bone and Mineral Research were present in the three cases. They had had unconsolidated fractures for approximately 1 yr before being referred to our center. After 3 months on strontium ranelate 2 g/d, serum osteocalcin and serum β-carboxyterminal telopeptide had increased in case 1 by 125 and 100%, respectively, and in case 2 by 50 and 22%, respectively, with total closure of the fracture. In case 3, after 1 month on teriparatide 20 μg/d, a radiographic closure of the fracture was achieved, and 3 months later serum osteocalcin and serum β-carboxyterminal telopeptide had increased by 300 and 22%, respectively.
  
  
  CONCLUSIONS
  Our finding showed that both teriparatide and strontium ranelate had a rapid bone anabolic effect on unhealed atypical fractures associated with chronic bisphosphonate use.
authors.affiliation: Division of Endocrinology, Agamenon Magalhães Hospital, University of Pernambuco Medical School, 52061-540 Recife, Brazil. naranc@gmail.com
authors.forename: N N C
authors.initials: NN
authors.lastname: Carvalho
authors.forename: L A
authors.initials: LA
authors.lastname: Voss
authors.forename: M O P
authors.initials: MO
authors.lastname: Almeida
authors.forename: C L
authors.initials: CL
authors.lastname: Salgado
authors.forename: F
authors.initials: F
authors.lastname: Bandeira
mesh_terms: D000368:Aged; D050071:Bone Density Conservation Agents / Q000009:adverse effects / Q000627:therapeutic use*; D004164:Diphosphonates / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D005264:Femoral Fractures / Q000209:etiology*; D006801:Humans; D008875:Middle Aged; D009942:Organometallic Compounds / Q000627:therapeutic use*; D010024:Osteoporosis / Q000188:drug therapy*; D019379:Teriparatide / Q000627:therapeutic use*; D013876:Thiophenes / Q000627:therapeutic use*
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D009942:Organometallic Compounds; D013876:Thiophenes; C081587:strontium ranelate; D019379:Teriparatide