title: Repair of failed transpedicle screw fixation. A biomechanical study comparing polymethylmethacrylate, milled bone, and matchstick bone reconstruction.
abstract: In a random, controlled laboratory study, pedicle screws placed in human cadaveric vertebrae were axially loaded to failure. Three repair methods were tested. Use of low pressure polymethylmethacrylate yielded 149% of the original pullout strength, milled bone yielded 70% of the initial pullout strength, and matchstick bone yielded 56% of the initial pullout strength. Two incidents of cortical penetration during reinsertion in the matchstick group occurred. The results were statistically analyzed.
authors.affiliation: Lahey Clinic, Boston, Massachusetts.
authors.forename: B A
authors.initials: BA
authors.lastname: Pfeifer
authors.forename: M H
authors.initials: MH
authors.lastname: Krag
authors.forename: C
authors.initials: C
authors.lastname: Johnson
mesh_terms: D001696:Biomechanical Phenomena; D001863:Bone Screws; D016025:Bone Transplantation / Q000379:methods*; D002102:Cadaver; D006801:Humans; D008768:Methylmethacrylates; D012086:Reoperation; D013131:Spine / Q000601:surgery*; D017211:Treatment Failure
chemical_list: D008768:Methylmethacrylates