title: Factors associated with outcome after subtalar arthrodesis.
abstract: OBJECTIVE
  To evaluate radiographic and functional outcomes after subtalar arthrodesis and to identify patient factors associated with poor outcome.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Two academic hospitals.
  
  
  METHODS
  Eighty-eight patients with primary or secondary osteoarthritis treated between 1995 and 2002.
  
  
  METHODS
  Primary subtalar arthrodesis.
  
  
  METHODS
  Radiographic outcome was assessed by determining union rates. Functional outcome was assessed through self-administered questionnaires (Short Form-36, Short Musculoskeletal Function Assessment, and the AAOS Foot and Ankle Instrument).
  
  
  RESULTS
  After adjusting for age and sex smokers were 3.8 times more likely to go on to nonunion than nonsmokers (P < 0.05). As patients aged, there was a higher likelihood of nonunion if they also smoked (P < 0.05). Of patients undergoing subtalar bone block distraction arthrodesis 95% went on to union compared with 65% of patients treated with an in situ subtalar arthrodesis without bone graft (P < 0.05). There was a trend for higher rates of union if a bone graft was used among patients treated with an in situ subtalar arthrodesis. Diabetic patients were 18.7 times more likely to have a malunion (P < 0.05). As a group, patients who have undergone subtalar arthrodesis can expect significantly worse functional outcomes compared with the Canadian and American normative populations. The poorest functional outcomes were observed among patients with diabetes. A trend for poorer outcome in bodily pain and general health (Short Form-36) was seen in workers' compensation patients.
  
  
  CONCLUSIONS
  Certain patient variables are associated with poorer outcomes after subtalar fusion. The results of this study will enable surgeons to provide better information to patients in preoperative discussions with respect to patient expectations, outcomes, and the success of surgery.
authors.affiliation: University of Toronto, Department of Surgery, Division of Orthopaedic Surgery, Canada.
authors.forename: Jaskarndip
authors.initials: J
authors.lastname: Chahal
authors.forename: David J G
authors.initials: DJ
authors.lastname: Stephen
authors.forename: Beverly
authors.initials: B
authors.lastname: Bulmer
authors.forename: Timothy
authors.initials: T
authors.lastname: Daniels
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Kreder
mesh_terms: D000328:Adult; D000368:Aged; D001174:Arthrodesis / Q000379:methods*; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D010003:Osteoarthritis / Q000145:classification / Q000000981:diagnostic imaging / Q000601:surgery*; D011859:Radiography; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires; D017211:Treatment Failure