Shear stability of an elastomeric disk spacer within an intervertebral joint: a parametric study.
A parametric study was conducted to compare the resistance to shear force provided by three surgical implantation techniques and three endplate designs for use with a polymeric lumbar intervertebral disk spacer. While under an axial load, the implant was pushed out laterally through the surgical window created for implantation. Force at 0.3 mm displacement, slope of the initial portion of the force-displacement graph, and maximum force were measured. The results indicate that implants with pegs, inclined planes, or domes on the surfaces of the disk will add significantly to the shear stability of the implant while maintaining the simplicity of a single part device.
Hawkins
M V
MV
University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Section of Orthopaedic Surgery, Newark 07103.
Zimmerman
M C
MC
Parsons
J R
JR
Carter
F M
FM
Langrana
N A
NA
Lee
C K
CK
D000818:Animals; D001696:Biomechanical Phenomena; D004285:Dogs; D004867:Equipment Design / Q000592:standards; D007405:Intervertebral Disc Displacement / Q000601:surgery*; D008422:Materials Testing; D019736:Prostheses and Implants / Q000592:standards*; D012408:Rubber / Q000592:standards*; D013314:Stress, Mechanical; D013718:Tensile Strength
D012408:Rubber