title: Composite piezoelectric spinal fusion implant: Effects of stacked generators.
abstract: Spinal fusion surgeries have a high failure rate for difficult-to-fuse patients. A piezoelectric spinal fusion implant was developed to overcome the issues with other adjunct therapies. Stacked generators were used to improve power generation at low electrical load resistances. The effects of the number of layers on average maximum power and the optimal electrical load resistance were characterized. The effects of mechanical preload, load frequency, and amplitude on maximum power and optimal electrical load resistance were also characterized. Increasing the number of layers from one to nine was found to lower the optimal electrical load resistance from 1.00 GΩ to 16.78 MΩ while maintaining maximum power generation. Mechanical preload did not have a significant effect on power output or optimal electrical load resistance. Increases in mechanical loading frequency increased average maximum power, while decreasing the optimal electrical load resistance. Increases in mechanical loading amplitude increased average maximum power output without affecting the optimal electrical load resistance.
authors: Bioengineering Graduate Program, University of Kansas, Lawrence, Kansas, 66045.
authors: Nathan C
authors: NC
authors: Goetzinger
authors: Department of Mechanical Engineering, University of Kansas, Lawrence, Kansas, 66045.
authors: Eric J
authors: EJ
authors: Tobaben
authors: Department of Mechanical Engineering, University of Kansas, Lawrence, Kansas, 66045.
authors: John P
authors: JP
authors: Domann
authors: Department of Neurosurgery, Kansas University Medical Center, Kansas City, Kansas, 66160.
authors: Paul M
authors: PM
authors: Arnold
authors: Bioengineering Graduate Program, University of Kansas, Lawrence, Kansas, 66045.|Department of Mechanical Engineering, University of Kansas, Lawrence, Kansas, 66045.
authors: Elizabeth A
authors: EA
authors: Friis
mesh_terms: D006801:Humans; D020007:Implants, Experimental; D008962:Models, Theoretical; D059745:Piezosurgery; D013123:Spinal Fusion
keywords: electrical stimulation; fusion; interbody; spine