title: Factors Associated with Increased Healing Time in Complete Femoral Fractures After Long-Term Bisphosphonate Therapy.
abstract: BACKGROUND
  The purpose of this study was to analyze factors that affect healing time after operative treatment of complete femoral fractures associated with long-term use of bisphosphonates. In particular, we sought to determine surgically controllable factors related to fracture-healing time.
  
  
  METHODS
  Ninety-nine consecutive patients (109 fractures) who had been surgically treated for a complete atypical femoral fracture were enrolled. All patients had a documented history of bisphosphonate therapy at the time of presentation, with an average duration of 7.4 ± 3.5 years (range, 3 to 20 years). Baseline demographic data, characteristics of the fracture and surgery, and radiographic findings including femoral neck-shaft angle, coronal and sagittal bowing of the femur, and thickness of the femoral cortex were examined. Univariate and multivariate logistic regression analyses were performed to identify predictive factors associated with delayed union or nonunion.
  
  
  RESULTS
  Of the 109 fractures, 76 (69.7%) showed osseous union within 6 months after the index surgery and were assigned to the successful healing group. The remaining 33 fractures (30.3%), which showed delayed union or nonunion, were assigned to the problematic healing group. There were differences in body mass index (BMI), bisphosphonate therapy duration, and the rate of prodromal symptoms between the 2 groups. Supra-isthmic fracture location, femoral bowing of ≥10° in the coronal plane, and a lateral/medial cortical thickness ratio of ≥1.4 were predictive of problematic healing but were uncontrollable factors. Iatrogenic cortical breakage around the fracture site as well as a ratio of ≥0.2 between the remaining gap and the cortical thickness on the anterior and lateral sides of the fracture site were controllable predictive factors associated with problematic healing.
  
  
  CONCLUSIONS
  Intramedullary nailing without cortical breakage around the fracture site and decreasing the anterior and lateral fracture gaps (avoidance of distraction) as much as possible are recommended to reduce healing time in complete femoral fractures associated with long-term use of bisphosphonates.
  
  
  METHODS
  Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: 1Department of Orthopaedic Surgery, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, South Korea 2Department of Orthopaedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea 3Department of Orthopaedic Surgery, Seoul Medical Center, Seoul, South Korea.
authors.forename: Hae-Seong
authors.initials: HS
authors.lastname: Lim
authors.forename: Chong-Kwan
authors.initials: CK
authors.lastname: Kim
authors.forename: Youn-Soo
authors.initials: YS
authors.lastname: Park
authors.forename: Young-Wan
authors.initials: YW
authors.lastname: Moon
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Lim
authors.forename: Sang-Min
authors.initials: SM
authors.lastname: Kim
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D050071:Bone Density Conservation Agents / Q000009:adverse effects* / Q000627:therapeutic use; D004164:Diphosphonates / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D005264:Femoral Fractures / Q000139:chemically induced / Q000188:drug therapy / Q000601:surgery*; D005269:Femur / Q000187:drug effects*; D017102:Fracture Healing / Q000187:drug effects*; D005599:Fractures, Ununited / Q000139:chemically induced*; D006801:Humans; D008297:Male; D010024:Osteoporosis / Q000188:drug therapy; D058866:Osteoporotic Fractures / Q000139:chemically induced / Q000188:drug therapy / Q000601:surgery; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates