title: Biomechanical evaluation of clavicle fracture plating techniques: does a locking plate provide improved stability?
abstract: OBJECTIVE
  To evaluate the biomechanical properties of both plate location (superior versus anterior-inferior) and plate type Small Fragment Contourable Dual Compression Plate (CDCP) versus 3.5 mm Universal Locking System Contourable Dual Compression Plate (Locked CDCP) in a synthetic midshaft transverse clavicle fracture model.
  
  
  METHODS
  Twenty-four pre-osteomized synthetic clavicles were repaired with either CDCP or locked CDCP technology 3.5 mm plates in either the superior or anterior-inferior position to form 4 groups of 6 clavicles. These were subsequently tested to evaluate torsional and axial construct stiffness, as well as bending load to failure, bending failure stiffness, and method of failure.
  
  
  RESULTS
  In axial compression, locked CDCP constructs were significantly more stiff than CDCP constructs (p < 0.001), but no statistically significant effect of plate location was observed. Torsional tests demonstrated a significant 2-way interaction favoring locked CDCP plates in the superior position and standard CDCP plates in the anterior-inferior position (p < 0.001). Bending failure testing revealed that the superior plate location had higher load to failure and bending failure stiffness than the anterior-inferior location (p < 0.0001). In addition, the superior locked CDCP plates demonstrated significantly greater bending failure stiffness than superior CDCP plates (p < 0.0001).
  
  
  CONCLUSIONS
  Biomechanically, repairing a midshaft clavicle fracture with a superior plate was more favorable compared to anterior-inferior plating in terms of both load to failure and bending failure stiffness. Furthermore, superior locked CDCP plates show improved bending failure stiffness over superior CDCP plates.
authors.affiliation: Department of Orthopaedic Surgery, University of California - San Diego, San Diego, California, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Celestre
authors.forename: Claire
authors.initials: C
authors.lastname: Roberston
authors.forename: Andrew
authors.initials: A
authors.lastname: Mahar
authors.forename: Richard
authors.initials: R
authors.lastname: Oka
authors.forename: Matthew
authors.initials: M
authors.lastname: Meunier
authors.forename: Alexandra
authors.initials: A
authors.lastname: Schwartz
mesh_terms: D001696:Biomechanical Phenomena; D001858:Bone Nails; D002968:Clavicle / Q000293:injuries*; D020099:Coated Materials, Biocompatible; D004868:Equipment Failure; D005593:Fracture Fixation, Internal / Q000295:instrumentation* / Q000379:methods; D050723:Fractures, Bone / Q000534:rehabilitation / Q000601:surgery; D006801:Humans; D019637:Orthopedic Procedures / Q000295:instrumentation* / Q000379:methods
chemical_list: D020099:Coated Materials, Biocompatible