title: Predicting alignment after closed reduction and casting of distal radius fractures.
abstract: OBJECTIVE
  We sought to independently validate the McQueen equation and LaFontaine's criteria as predictors of instability in a large series of distal radius fractures treated nonsurgically. In addition, we hypothesized that restoring the volar cortical integrity (ie, volar hook) would be another factor that would independently predict the maintenance of a closed reduction in a cast.
  
  
  METHODS
  We screened 546 consecutive distal radius fractures with 168 meeting all inclusion criteria. Dorsal tilt, radial height, radial inclination, ulnar variance, and carpal malalignment were measured on initial postreduction and final radiographs. A univariate analysis evaluated the predictability of the McQueen equation, Lafontaine's criteria, and volar hook on each radiographic parameter. A multivariate analysis was performed using the significant results from the univariate analysis.
  
  
  RESULTS
  In the univariate analysis, the McQueen formula, the number of Lafontaine criteria, and age all correlated with radial height, radial inclination, and ulnar variance. In the multivariate analysis, age correlated with the most radiographic factors including radial height, radial inclination, ulnar variance, and carpal alignment at healing. Volar hook correlated with dorsal tilt and carpal alignment at healing, and dorsal comminution correlated with dorsal tilt.
  
  
  CONCLUSIONS
  In the nonsurgical treatment of distal radius fractures, we were able to validate the McQueen equation and Lafontaine's criteria in predicting the final radial height and inclination and final ulnar variance. Neither method was predictive of final dorsal tilt or carpal malalignment. However, restoring volar cortical continuity by hooking the volar cortex in the initial reduction proved to be the strongest predictor of final volar tilt, the change in volar tilt, and carpal malalignment at union.
  
  
  METHODS
  Therapeutic III.
authors.affiliation: Department of Orthopedics, Boston University Medical Center, Boston, MA; Department of Orthopedics, New England Baptist Hospital, Boston, MA.
authors.forename: Joey
authors.initials: J
authors.lastname: LaMartina
authors.affiliation: Department of Orthopedics, Boston University Medical Center, Boston, MA; Department of Orthopedics, New England Baptist Hospital, Boston, MA. Electronic address: ajawa@nebh.org.
authors.forename: Andrew
authors.initials: A
authors.lastname: Jawa
authors.affiliation: Department of Orthopedics, Boston University Medical Center, Boston, MA; Department of Orthopedics, New England Baptist Hospital, Boston, MA.
authors.forename: Charlton
authors.initials: C
authors.lastname: Stucken
authors.affiliation: Department of Orthopedics, Boston University Medical Center, Boston, MA; Department of Orthopedics, New England Baptist Hospital, Boston, MA.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Merlin
authors.affiliation: Department of Orthopedics, Boston University Medical Center, Boston, MA; Department of Orthopedics, New England Baptist Hospital, Boston, MA.
authors.forename: Paul
authors.initials: P
authors.lastname: Tornetta
mesh_terms: D000293:Adolescent; D000328:Adult; D017760:Bone Malalignment / Q000000981:diagnostic imaging* / Q000517:prevention & control; D002370:Casts, Surgical; D005260:Female; D005592:Fracture Fixation / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011859:Radiography; D011885:Radius Fractures / Q000000981:diagnostic imaging / Q000628:therapy*; D016896:Treatment Outcome
keywords: Alignment; casting; distal radius; fracture