In vitro testing of a new transpedicular stabilization technique

M Pfeiffer; H Hoffman; V K Goel; J N Weinstein; P Griss

doi:10.1007/BF01322447

Back

In vitro testing of a new transpedicular stabilization technique

Journal article

Open access

Peer reviewed

In vitro testing of a new transpedicular stabilization technique

M Pfeiffer, H Hoffman, V K Goel, J N Weinstein and P Griss

European spine journal, Vol.6(4), pp.249-255

1997

DOI: 10.1007/BF01322447

PMCID: PMC3454640

PMID: 9294749

Files and links (1)

url

https://europepmc.org/articles/pmc3454640View

Published (Version of record) Open Access

Abstract

The rigidity of a pedicle screw implant is a critical biomechanical variable in lumbar spinal fusions. Sufficient rigidity is required for integration of bone grafts and to promote healing. Osteopenia, stress shielding, and compensatory hypermobility have been described as consequences of excessive rigidity. Little is known about the biomechanical characteristics of "semirigid" compared to "rigid" implants. A new implant, whose rigidity can be varied by selection of different implant components, was tested in vitro under well-defined loading conditions. The three-dimensional load-displacement behavior of all lumbar vertebrae involved in or adjacent to the two-level fusion was evaluated for two fusion modifications: bilateral rigid and bilateral semirigid. Cyclic fatigue loading was subsequently carried out under realistic conditions and motion testing repeated. The rigid device reduced the motion of the L3-4 transfixed segment in the primary movement planes by 87.3% with respect to the intact spine value in flexion/extension (FE), 86.3% in lateral bending (LB), and 76.8% in axial rotation (AR). The semirigid device achieved a reduction in motion of 79.6% (FE), 82.7% (LB), and 51.7% (AR). The semirigid implant was particularly easy to insert, because no bending of rods or plates was necessary. The implants showed no loosening or breakage after the fatigue testing. The results are compared to other available systems and the underlying biomechanics discussed.

Aged

Aged, 80 and over

Cadaver

Female

Humans

Joint Instability - physiopathology

Joint Instability - surgery

Lumbosacral Region

Male

Materials Testing

Middle Aged

Orthopedic Fixation Devices - standards

Orthopedics - methods

Range of Motion, Articular

Spinal Diseases - physiopathology

Spinal Diseases - surgery

Spinal Fusion

Spine - physiopathology

Weight-Bearing - physiology

Details

Title: Subtitle: In vitro testing of a new transpedicular stabilization technique
Creators: M Pfeiffer - Philipps University of Marburg
H Hoffman - University of Iowa
V K Goel - University of Iowa
J N Weinstein - University of Iowa
P Griss - Philipp University of Marburg
Resource Type: Journal article
Publication Details: European spine journal, Vol.6(4), pp.249-255
DOI: 10.1007/BF01322447
PMID: 9294749
PMCID: PMC3454640
NLM abbreviation: Eur Spine J
ISSN: 0940-6719
eISSN: 1432-0932
Language: English
Date published: 1997
Academic Unit: Radiation Oncology; Otolaryngology
Record Identifier: 9984313997202771

Metrics

11 Record Views