title: Outcomes between older adults with atypical and typical femoral fractures are comparable.
abstract: BACKGROUND
  Atypical femoral fractures (AFFs) are rare but a serious complication associated with prolonged use of bisphosphonates. However little is known about clinical outcomes of AFFs. The aim of this study is to compare the characteristics and postoperative outcomes between older patients with AFFs and typical femoral fractures (TFFs).
  
  
  METHODS
  A retrospective matched cohort study (each AFF was age- and sex-matched with three TFFs) of patients aged 65 years or older who were admitted to The Queen Elizabeth Hospital, South Australia between January 2011 and December 2013 was undertaken. Baseline characteristics of both groups were compared. The primary outcomes evaluated were level of independence in mobility at discharge and 3 months after surgery. Secondary outcomes included length of hospital stay, post-operative complications, rate of surgical revision, discharge destination (after acute hospital stay or rehabilitation), 28-day hospital readmission and 12-month mortality.
  
  
  RESULTS
  Ten patients (mean age: 78.1 years) with AFFs were compared with 30 matched TFFs. Patients with AFFs were predominantly female (90%) and 80% had been taking oral bisphosphonate. Nine of the AFFs had their fractures fixed with an intramedullary (IM) nail. The level of independent mobility at discharge (OR 0.31; 95%CI: 0.06-1.71; p=0.26) and at 3 months (OR 0.51; 95%CI: 0.10-2.53; p=0.47) were comparable between the two groups. Only one AFF patient treated with plate and screws required surgical revision, compared with none in the TFF group. Secondary outcomes were not significantly different between the two groups.
  
  
  CONCLUSIONS
  Recovery of mobility and reoperation rates after surgery of patients with AFFs were favourable and did not differ significantly from TFFs. Further consideration should be given to using IM fixation in the management of AFFs in older people.
authors.affiliation: Aged and Extended Care Services, The Queen Elizabeth Hospital, Australia; National Health and Medical Research Council Centre of Research Excellence Trans-disciplinary Frailty Research to Achieve Healthy Aging, Australia; Adelaide Geriatrics Training and Research with Aged Care (G-TRAC) Centre, School of Medicine, University of Adelaide, Adelaide, Australia. Electronic address: kareeann.khow@adelaide.edu.au.
authors.forename: Kareeann S F
authors.initials: KS
authors.lastname: Khow
authors.affiliation: Department of Radiology, Royal Adelaide Hospital, Adelaide, Australia.
authors.forename: Felix
authors.initials: F
authors.lastname: Paterson
authors.affiliation: Aged and Extended Care Services, The Queen Elizabeth Hospital, Australia; National Health and Medical Research Council Centre of Research Excellence Trans-disciplinary Frailty Research to Achieve Healthy Aging, Australia; Adelaide Geriatrics Training and Research with Aged Care (G-TRAC) Centre, School of Medicine, University of Adelaide, Adelaide, Australia.
authors.forename: Pazhvoor
authors.initials: P
authors.lastname: Shibu
authors.affiliation: Aged and Extended Care Services, The Queen Elizabeth Hospital, Australia; National Health and Medical Research Council Centre of Research Excellence Trans-disciplinary Frailty Research to Achieve Healthy Aging, Australia; Adelaide Geriatrics Training and Research with Aged Care (G-TRAC) Centre, School of Medicine, University of Adelaide, Adelaide, Australia.
authors.forename: Solomon C Y
authors.initials: SC
authors.lastname: Yu
authors.affiliation: National Health and Medical Research Council Centre of Research Excellence Trans-disciplinary Frailty Research to Achieve Healthy Aging, Australia; Discipline of Orthopaedics and Trauma, Royal Adelaide Hospital, Adelaide, Australia.
authors.forename: Mellick J
authors.initials: MJ
authors.lastname: Chehade
authors.affiliation: Aged and Extended Care Services, The Queen Elizabeth Hospital, Australia; National Health and Medical Research Council Centre of Research Excellence Trans-disciplinary Frailty Research to Achieve Healthy Aging, Australia; Adelaide Geriatrics Training and Research with Aged Care (G-TRAC) Centre, School of Medicine, University of Adelaide, Adelaide, Australia.
authors.forename: Renuka
authors.initials: R
authors.lastname: Visvanathan
mesh_terms: D000058:Accidental Falls; D000368:Aged; D001315:Australia / Q000453:epidemiology; 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 / Q000453:epidemiology / Q000601:surgery*; D017102:Fracture Healing; D005598:Fractures, Spontaneous / Q000139:chemically induced / Q000453:epidemiology / Q000601:surgery*; D006801:Humans; D008297:Male; D010024:Osteoporosis / Q000150:complications / Q000188:drug therapy* / Q000453:epidemiology; D063868:Patient Outcome Assessment; D012189:Retrospective Studies
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates
keywords: Atypical femoral fracture; Bisphosphonates; Femoral fracture; Mobility; Outcomes; Subtrochanteric fracture