title: Superior pubic ramus fractures fixed with percutaneous screws: what predicts fixation failure?
abstract: OBJECTIVE
  The purpose of this study is to present the early complications of percutaneous screw fixation of superior pubic ramus fractures and to present a new classification scheme for superior pubic ramus fractures.
  
  
  METHODS
  Retrospective.
  
  
  METHODS
  Level 1 trauma center.
  
  
  METHODS
  One hundred and twelve patients with pelvic fracture between the ages of 14 to 89 years underwent percutaneous screw fixation of 145 pubic ramus fractures. Eighty-one patients with 107 surgically repaired fractures were followed to fracture union. Follow-up averaged 9 months (range 2-52 months). One additional patient who sustained fixation failure 4 days after surgery was included to yield a study group of 82 patients with 108 surgically repaired ramus fractures.
  
  
  METHODS
  Patients underwent percutaneous screw fixation of a superior pubic ramus fracture.
  
  
  METHODS
  Superior pubic ramus fractures were classified according to a new scheme, the Nakatani system, which categorizes superior ramus fractures according to location with respect to the obturator foramen. Patient radiographs were examined for evidence of loss of reduction, defined as any motion at the ramus fracture site or hardware motion, after fracture surgery.
  
  
  RESULTS
  Of the 82 patients followed to union or fixation failure, 12 (15%) had loss of reduction on follow-up radiographs. The average age of patients who lost reduction was 55 years. The most common mechanism of reduction loss was a collapse of the pubic ramus over the screw, with recurrence of an internal rotation deformity of the injured hemipelvis. Ten patients who lost reduction were women, and 11 had undergone ramus screw placement in retrograde fashion. No loss of reduction was seen in Zone III ramus fractures (those that involve the bone lateral to the obturator foramen). No patient sustained recognized neurologic, vascular, or urologic injury as a result of percutaneous screw fixation of a superior pubic ramus fracture.
  
  
  CONCLUSIONS
  The prevalence of loss of reduction after percutaneous screw fixation of pubic ramus fractures is 15%. Loss of reduction is more common in elderly and female patients and in patients whose ramus screws are placed in a retrograde fashion. Also, loss of reduction appears to be more common in fractures medial to the lateral border of the obturator foramen.
authors: Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas, Texas 75390-8883, USA. Adam.Starr@utsouthwestern.edu
authors: Adam J
authors: AJ
authors: Starr
authors: Tetsuya
authors: T
authors: Nakatani
authors: Charles M
authors: CM
authors: Reinert
authors: Kevin
authors: K
authors: Cederberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001863:Bone Screws; D005260:Female; D005471:Fluoroscopy; D005593:Fracture Fixation, Internal / Q000009:adverse effects*; D050723:Fractures, Bone / Q000145:classification / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011630:Pubic Bone / Q000293:injuries*; D012189:Retrospective Studies; D017211:Treatment Failure