title: Nonunion After Clavicle Osteosynthesis: High Incidence of Propionibacterium acnes.
abstract: OBJECTIVE
  The objective of this study was to review the etiology of clavicle nonunions after osteosynthesis and investigate the outcomes of a treatment with a single-stage revision.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  Orthopaedic specialty hospital.
  
  
  METHODS
  Twenty cases of nonunion after osteosynthesis of the clavicle were identified. The average age was 44 years (±13 years). In 9 cases, there was catastrophic implant failure that prompted the revision surgery. In the 18 cases in which cultures were taken, 15 of the 18 (83%) were treated as infections with a course of antibiotics. In 14 cases, the cultures were positive for Propionibacterium acnes.
  
  
  RESULTS
  Fifteen patients were treated with a prolonged course of antibiotics. Eighteen patients had follow-up, and the average time to radiographic union was 22 weeks. There were no cases of nonunion after revision surgery.
  
  
  CONCLUSIONS
  There is a high rate of positive cultures in cases of nonunion after osteosynthesis of the clavicle. This suggests the etiology of midshaft clavicle nonunions may result from a combination of suboptimal mechanical fixation and latent infection. Our treatment protocol of superior and anterior plating, interfragmentary fixation, bone grafting, and appropriate antimicrobial treatment of latent infections has resulted in 100% union rate.
  
  
  METHODS
  Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: *Hospital for Special Surgery, New York, NY; and †Department of Orthopaedic Surgery, Weill Cornell Medical College, New York, NY.
authors.forename: Elizabeth B
authors.initials: EB
authors.lastname: Gausden
authors.forename: Jordan
authors.initials: J
authors.lastname: Villa
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Warner
authors.forename: Mariya
authors.initials: M
authors.lastname: Redko
authors.forename: Andrew
authors.initials: A
authors.lastname: Pearle
authors.forename: Andy
authors.initials: A
authors.lastname: Miller
authors.forename: Michael
authors.initials: M
authors.lastname: Henry
authors.forename: Dean G
authors.initials: DG
authors.lastname: Lorich
authors.forename: David L
authors.initials: DL
authors.lastname: Helfet
authors.forename: David S
authors.initials: DS
authors.lastname: Wellman
mesh_terms: D000328:Adult; D002968:Clavicle / Q000293:injuries* / Q000382:microbiology / Q000601:surgery; D005260:Female; D005593:Fracture Fixation, Internal / Q000009:adverse effects*; D050723:Fractures, Bone / Q000453:epidemiology / Q000382:microbiology / Q000601:surgery*; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology* / Q000382:microbiology; D006801:Humans; D015994:Incidence; D008297:Male; D011425:Propionibacterium acnes; D012189:Retrospective Studies; D012307:Risk Factors; D013530:Surgical Wound Infection / Q000175:diagnosis / Q000209:etiology* / Q000382:microbiology; D017211:Treatment Failure