title: Correlation between metal allergy and treatment outcomes after ankle fracture fixation.
abstract: OBJECTIVE
  To determine correlation between metal hypersensitivity and long-term foot and ankle function and pain after internal fixation using stainless steel implants.
  
  
  METHODS
  60 men and 46 women (mean age, 47 years) who underwent internal fixation for ankle fractures completed a questionnaire 13 to 38 (mean, 26) months after surgery to assess their existing medical condition, history of metal hypersensitivity, problems and outcome of the implant (revision or removal), and the American Academy of Orthopaedic Surgeons (AAOS) foot and ankle score. A subset of 12 men and 15 women then underwent patch testing for metal hypersensitivity to molybdenum, chromium, iron, manganese, and nickel. Patients with positive and negative reactions were compared.
  
  
  RESULTS
  21 of the 106 patients underwent removal of the metal implants. The AAOS score was not associated with any of the variables, except for a history of metal hypersensitivity from dental implants and irritation around the surgical scar. Multiple linear regression analysis showed that only irritation around the surgical scar remained associated with poorer AAOS scores. Five of the 27 tested patients had a positive reaction. The mean AAOS scores did not differ significantly between patients with positive and negative reactions (34 vs. 31, p=0.73). Gender was not associated with the test results (p=0.63). None of the 5 patients with a positive reaction underwent revision surgery or reported any history of asthma or metal hypersensitivity. Of the 27 patients, one of the 8 who reported itching, irritation, redness or rash around the surgical scar had a positive reaction, compared to 4 of 19 patients who reported no such symptoms (p=1). Two of the 27 patients reported development of eczema after fixation, one of whom had a positive reaction. Only one of the 27 patients reported a history of metal hypersensitivity to jewellery, but had a negative reaction..
  
  
  CONCLUSIONS
  Neither a history of metal hypersensitivity nor positive patch testing correlated with poor outcomes after internal fixation for ankle fractures using stainless steel implants.
authors.affiliation: South West Sydney Clinical School, University of New South Wales, Australia.
authors.forename: Sarah
authors.initials: S
authors.lastname: So
authors.forename: Ian A
authors.initials: IA
authors.lastname: Harris
authors.forename: Justine M
authors.initials: JM
authors.lastname: Naylor
authors.forename: Sam
authors.initials: S
authors.lastname: Adie
authors.forename: Rajat
authors.initials: R
authors.lastname: Mittal
mesh_terms: D000328:Adult; D000368:Aged; D016512:Ankle Injuries / Q000601:surgery*; D005260:Female; D005593:Fracture Fixation, Internal / Q000295:instrumentation; D050723:Fractures, Bone / Q000601:surgery*; D006801:Humans; D006967:Hypersensitivity; D055498:Jewelry; D008297:Male; D008875:Middle Aged; D019736:Prostheses and Implants; D013193:Stainless Steel / Q000009:adverse effects*; D013639:Tarsal Bones / Q000293:injuries*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D013193:Stainless Steel