title: Variable-angle locking plate with or without double-tiered subchondral support procedure in the treatment of intra-articular distal radius fracture.
abstract: BACKGROUND
  Double-tiered subchondral support (DSS) procedure is two-row fixation in which proximal screws support the dorsal subchondral bone, whereas distal screws support the volar central subchondral bone, using the volar variable-angle locking plate to achieve better anatomical reduction. We examined whether DSS improves clinical outcome, complication rate, and loss of correction for dorsally displaced Arbeitsgemeinschaft für Osteosynthesefragen (AO) type C3 distal radius fractures.
  
  
  METHODS
  We reviewed dorsally displaced intra-articular AO C3-type distal radius fractures treated at our institutions with a variable-angle volar locking plate. We assessed 49 patients (27 DSS; 22 non-DSS) treated with volar locking plates, with a mean age of 59.9 years and average follow-up of 20.2 months (range 12-56 months). We evaluated differences in functional outcome, complication rates, and loss of correction between groups using radiographic parameters.
  
  
  RESULTS
  There were no differences in clinical outcome and complications. Final volar tilt and ulnar variance were better maintained in the DSS group (P = 0.01 and 0.03). Change in volar tilt of the non-DSS group was more than that of the DSS group (P = 0.00).
  
  
  CONCLUSIONS
  Though there were no significant differences in clinical outcomes, we identified a significant reduction in final volar tilt, ulnar variance, and change in volar tilt. DSS procedure is useful to avoid correction loss when treating unstable C3 distal radius fractures and thus would reduce posttraumatic arthrosis.
  
  
  METHODS
  Level IV.
authors.affiliation: Department of Orthopaedic Surgery, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8666, Japan, kawa@j07.itscom.net.
authors.forename: Keikichi
authors.initials: K
authors.lastname: Kawasaki
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Nemoto
authors.forename: Katsunori
authors.initials: K
authors.lastname: Inagaki
authors.forename: Kazunari
authors.initials: K
authors.lastname: Tomita
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ueno
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001860:Bone Plates; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal / Q000295:instrumentation* / Q000379:methods*; D017102:Fracture Healing / Q000502:physiology; D018737:Hand Strength; D006801:Humans; D015601:Injury Severity Score; D057072:Intra-Articular Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D007593:Joint Instability / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D011859:Radiography; D011885:Radius Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D016059:Range of Motion, Articular / Q000502:physiology*; D012189:Retrospective Studies; D054457:Tissue Scaffolds; D016896:Treatment Outcome; D014954:Wrist Injuries / Q000000981:diagnostic imaging / Q000601:surgery; D055815:Young Adult