title: Incidence and Risk Factors for Extensor Pollicis Longus Rupture in Elastic Stable Intramedullary Nailing of Pediatric Forearm Shaft Fractures.
abstract: BACKGROUND
  Elastic stable intramedullary nailing (ESIN) is an effective means of fixation for unstable, pediatric forearm shaft fractures with the benefit of smaller incisions, less soft tissue manipulation, and ease of removal. This study was designed to evaluate the incidence of and risk factors for extensor pollicis longus (EPL) rupture after fixation of pediatric radial shaft fractures with ESIN.
  
  
  METHODS
  A retrospective review of all patients younger than 19 years who had a repair of a forearm fracture with flexible intramedullary nailing between 2006 and 2011 was performed. Nineteen consecutive patients were identified from the electronic medical record. All patients were treated with a titanium elastic nailing system using a dorsal approach to the radius. The patients were followed postoperatively for at least 2 years, and all fractures healed. An extensive chart review assessing for persistent pain, EPL function, and risk factors for EPL rupture was performed. Implants were removed in all but 1 patient.
  
  
  RESULTS
  Seventeen records were available for review. Fourteen (82%) were male, and the mean age at time of fracture was 10 years old (range, 5 to 14 y). Follow-up averaged 5.5 years (range, 2.9 to 7.8 y). The mean weight was 32.7 kg for males and 50.6 kg for females corresponding to the 61st and 60th percentile respectively of weight-for-age (range, 8th to 99.9th percentile). Hardware was removed in all but 1 case, and the median time from surgery to hardware removal was 21 weeks (range, 8 to 63). Three of the 17 patients (18%) experienced rupture of the EPL. Two were treated with additional surgery following hardware removal, and one was untreated due to patient preference. None of the 17 patients (including those with rupture) had independent risk factors for tendon rupture: inflammatory arthritis, diabetes, or prior steroid use. Time to removal, patient age, and percentile of weight-for-age did not correlate with EPL rupture.
  
  
  CONCLUSIONS
  Although ESIN of pediatric forearm shaft fractures has gained acceptance as a treatment option, our series of 17 patients revealed an 18% rate of EPL rupture. With this small patient cohort, no patient characteristics proved to be significant risk factors for predicting tendon rupture. However, awareness should be raised for an increased risk of EPL rupture with this fixation method.
  
  
  METHODS
  Level IV-Therapeutic.
authors.affiliation: *Geisinger Medical Center, Danville, PA †Washington Hand Surgery, Kirkland, WA.
authors.forename: Adam K
authors.initials: AK
authors.lastname: Lee
authors.forename: John D
authors.initials: JD
authors.lastname: Beck
authors.forename: William M
authors.initials: WM
authors.lastname: Mirenda
authors.forename: Joel C
authors.initials: JC
authors.lastname: Klena
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D005543:Forearm Injuries / Q000175:diagnosis / Q000601:surgery*; D005594:Fracture Fixation, Intramedullary / Q000379:methods*; D006801:Humans; D015994:Incidence; D008297:Male; D011885:Radius Fractures / Q000175:diagnosis / Q000601:surgery*; D012189:Retrospective Studies; D012307:Risk Factors; D012421:Rupture; D013708:Tendon Injuries / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery; D014481:United States / Q000453:epidemiology; D055815:Young Adult