Repair of failed transpedicle screw fixation. A biomechanical study comparing polymethylmethacrylate, milled bone, and matchstick bone reconstruction.
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.
Pfeifer
B A
BA
Lahey Clinic, Boston, Massachusetts.
Krag
M H
MH
Johnson
C
C
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
D008768:Methylmethacrylates