title: The Effect of Obesity on Functional Outcomes and Complications in Total Ankle Arthroplasty.
abstract: BACKGROUND
  The prevalence of obesity in the United States is staggering. Currently, the effect of obesity on third-generation total ankle replacement (TAR) is unknown.
  
  
  METHODS
  We prospectively identified a consecutive series of 455 primary TARs operated between May 2007 and September 2013 who had a minimum follow-up of 2 years. We identified 266 patients with a body mass index (BMI) <30 (control), 116 with a BMI between 30 and 35 (Obese I), and 73 with a BMI >35 (Obese II). Clinical outcomes including wound issues, infection rate, complications, and failure rates were compared. Functional outcomes including American Orthopaedic Foot & Ankle Society hindfoot score, Short Form-36 (SF-36), Short Musculoskeletal Function Assessment (SMFA), Foot and Ankle Disability Index (FADI), and Foot and Ankle Outcome Score (FAOS) were compared. Average patient follow-up in the Obese I group was 44.7 ± 17.3 months, Obese II was 42.7 ± 16.4 months, and 45.2 ± 17.4 months in the control group.
  
  
  RESULTS
  Age, race, and smoking history in the obese group were not significantly higher than the control group; however, sex was significantly related to BMI. There was no difference in complication, infection, or failure rates between the groups. Preoperatively, the Obese II group had significantly lower SF-36 scores and higher SMFA function, FADI, and FAOS Symptoms scores. For each of the Obese I, Obese II, and control groups, all functional outcome scores 1 year postoperatively and at most recent follow-up were significantly improved. However, at most recent follow-up, Obese II patients had lower FAOS Pain and SF-36 scores and higher FADI and SMFA Functional scores.
  
  
  CONCLUSIONS
  Total ankle arthroplasty in obese patients was a relatively safe procedure. Although obese patients after TAR had lower functional outcome scores compared to their nonobese counterpart, they did experience significant functional and pain improvements at most recent follow-up.
  
  
  METHODS
  Level III, comparative series.
authors.affiliation: Department of Orthopaedic Surgery, Medical University of South Carolina, Charleston, SC, USA cgross144@gmail.com.
authors.forename: Christopher E
authors.initials: CE
authors.lastname: Gross
authors.affiliation: Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Lampley
authors.affiliation: Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC, USA.
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Green
authors.affiliation: Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: James K
authors.initials: JK
authors.lastname: DeOrio
authors.affiliation: Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Easley
authors.affiliation: Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: Samuel
authors.initials: S
authors.lastname: Adams
authors.affiliation: Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: James A
authors.initials: JA
authors.lastname: Nunley
mesh_terms: D058737:Arthroplasty, Replacement, Ankle; D015992:Body Mass Index; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D010146:Pain / Q000601:surgery; D063868:Patient Outcome Assessment; D011446:Prospective Studies; D016459:Prosthesis-Related Infections; D011788:Quality of Life
keywords: obesity; outcome studies; total ankle arthroplasty