title: Biomechanical evaluation of intramedullary nail versus tension band fixation for transverse olecranon fractures.
abstract: OBJECTIVE
  To compare the biomechanical stability of an alternative custom-designed intramedullary nail (IMN) fixation with that of traditional tension band wiring (TBW), the gold standard for stabilizing transverse olecranon fractures.
  
  
  METHODS
  Ex vivo biomechanical study.
  
  
  METHODS
  Biomechanical laboratory.
  
  
  METHODS
  Six pairs of elderly cadaver elbows.
  
  
  METHODS
  A simulated transverse olecranon fracture was created in each elbow after it had been denuded of most of its soft tissue. The right and left olecranons of each pair were alternately assigned to the IMN or TBW group. A tensile force was applied via the triceps tendon while the elbow was secured in 90 degree of flexion.
  
  
  METHODS
  Displacement at the simulated fracture segment was measured optically. Fixation failure was defined as >2 mm of fracture displacement. The differences in stiffness and maximum load to failure between the two treatments were analyzed for significance (P < 0.05) using a one-tailed paired t test.
  
  
  RESULTS
  IMN fixation was significantly stiffer and stronger than TBW fixation.
  
  
  CONCLUSIONS
  The locked IMN provided stronger and stiffer fixation than did TBW. Theoretically the IMN fixation would require less surgical exposure and would be expected to require fewer revisions than TBW fixation. IMN fixation warrants consideration as a clinical alternative to TBW.
authors.affiliation: Department of Orthopaedic Surgery, Johns Hopkins University/Johns Hopkins Bayview Medical Center, Baltimore, MD 21224-2780, USA.
authors.forename: Sean
authors.initials: S
authors.lastname: Molloy
authors.forename: Louis E
authors.initials: LE
authors.lastname: Jasper
authors.forename: David S
authors.initials: DS
authors.lastname: Elliott
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Brumback
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Belkoff
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D001858:Bone Nails; D002102:Cadaver; D005260:Female; D005594:Fracture Fixation, Intramedullary / Q000295:instrumentation* / Q000379:methods; D050723:Fractures, Bone / Q000601:surgery; D006801:Humans; D004204:Joint Dislocations / Q000601:surgery*; D007593:Joint Instability / Q000517:prevention & control; D008297:Male; D011336:Probability; D016059:Range of Motion, Articular / Q000502:physiology; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D000092464:Elbow Injuries