title: Pedicle Screw Configuration for Thoracolumbar Burst Fracture Treatment: Short versus Long Posterior Fixation Constructs with and without Anterior Column Augmentation.
abstract: METHODS
  An in-vitro study.
  
  
  OBJECTIVE
  The current study is aimed at investigating the differences in stability between short posterior fixation (SPF), hybrid posterior fixation (HPF), and long posterior fixation (LPF) with and without anterior column augmentation using calcium phosphate bone cement (CaP) for treating burst fractures (BFs).
  
  
  BACKGROUND
  The ideal treatment for thoracolumbar BF is controversial regarding the use of short or LPF constructs.
  
  
  METHODS
  Seven human thoracolumbar spines (T9-L4) were tested on a six degree of freedom spine simulator in three physiologic planes, flexion-extension (FE), lateral bending (LB), and axial rotation (AR). Tested surgical constructs included the following: intact, injury (BF), SPF (T12-L2), HPF (T11-L2), LPF (T11-L3), SPF+CaP, HPF+CaP, LPF+CaP, and CaP alone (CaP). Range of motion (ROM) was recorded at T12-L2 in FE, LB, and AR.
  
  
  RESULTS
  THE REDUCTION IN MEAN ROM TRENDED AS FOLLOWS: LPF>HPF>SPF. Only LPF constructs and HPF with anterior column augmentation significantly reduced mean ROM in FE and LB compared to the intact state. All instrumented constructs (SPF, HPF, and LPF) significantly reduced ROM in FE and LB compared to the injured condition. Furthermore, the instrumented constructs did not provide significant rotational stability. Injecting CaP provided minimal additional stability.
  
  
  CONCLUSIONS
  For the injury created, LPF and HPF provided better stability than SPF with and without anterior column augmentation. Therefore, highly unstable fractures may require extended, long or hybrid fusion constructs for optimum stability.
authors.affiliation: One Brain and Spine Center, Newport Beach, CA, USA.
authors.forename: Todd
authors.initials: T
authors.lastname: Peters
authors.affiliation: Globus Medical Inc., Audubon, PA, USA.
authors.forename: Suresh Reddy
authors.initials: SR
authors.lastname: Chinthakunta
authors.affiliation: Globus Medical Inc., Audubon, PA, USA.
authors.forename: Mir
authors.initials: M
authors.lastname: Hussain
authors.affiliation: Globus Medical Inc., Audubon, PA, USA.
authors.forename: Saif
authors.initials: S
authors.lastname: Khalil
keywords: Bone cements; Bone screws; Fracture fixations; Spine