Biomechanical comparison of bone-screw–fasteners versus traditional locked screws in plating female geriatric bone

Summary Objective: To compare the biomechanical properties of simulated humeral condylar fractures reduced with one of two screw fixation methods: 3.0 mm headless compression screw (HCS) or 3.5 mm cortical bone screw (CBS) placed in lag fashion. Methods: Bilateral humeri were collected from nine canine cadavers. Standardized osteotomies were stabilized with 3.0 mm HCS in one limb and 3.5 mm CBS in the contralateral limb. Condylar fragments were loaded to walk, trot, and failure loads while measuring construct properties and condylar fragment motion. Results: The 3.5 mm CBS-stabilized constructs were 36% stiffer than 3.0 mm HCS-stabilized constructs, but differences were not apparent in quality of fracture reduction nor in yield loads, which exceeded expected physiological loads during rehabilitation. Small residual fragment displacements were not different between CBS and HCS screws. Small fragment rotation was not significantly different between screws, but was weakly correlated with moment arm length (R2 = 0.25). Clinical significance: A CBS screw placed in lag fashion provides stiffer fixation than an HCS screw, although both screws provide similar anatomical reduction and yield strength to condylar fracture fixation in adult canine humeri.

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A Biomechanical Comparison of a Novel Thoracic Screw Fixation Method: Transarticular Screw Fixation vs Traditional Pedicle Screw Fixation

Yearbook of Neurology and Neurosurgery ◽

10.1016/j.yneu.2012.01.006 ◽

2012 ◽

Vol 2012 ◽

pp. 272-274

Author(s):

R. Riesenburger

Keyword(s):

Pedicle Screw ◽

Screw Fixation ◽

Pedicle Screw Fixation ◽

Fixation Method ◽

Transarticular Screw ◽

Transarticular Screw Fixation ◽

Biomechanical Comparison

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Pullout Strength of Screws in Foal Third Metacarpal Bone after Overdrilling a 4.5 mm Hole

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1632548 ◽

1998 ◽

Vol 11 (04) ◽

pp. 200-204 ◽

Cited By ~ 1

Author(s):

K. Kelly ◽

G. S. Martin ◽

D. J. Burba ◽

S. A. Sedrish ◽

R. M. Moore

Keyword(s):

Cortical Bone ◽

Metacarpal Bone ◽

Pullout Strength ◽

Cancellous Screw ◽

Bone Screw ◽

Screw Insertion ◽

Holding Power ◽

Cortical Screw ◽

Metaphyseal Bone

SummaryThe purpose of the study was to determine and to compare the in vitro pullout strength of 5.5 mm cortical versus 6.5 mm cancellous bone screws inserted in the diaphysis and metaphysis of foal third metacarpal (MCIII) bones in threaded 4.5 mm cortical bone screw insertion holes that were then overdrilled with a 4.5 mm drill bit. This information is relevant to the selection of a replacement screw if a 4.5 mm cortical screw is stripped during orthopaedic surgery. In vitro pullout tests were performed in two independent cadaver studies, each consisting of 12 foal MCIII bones. Two 4.5 mm cortical screws were placed either in the mid-diaphysis (study 1) or distal metaphysis (study 2) of MCIII bones. The holes were then overdrilled with a 4.5 mm bit and had either a 5.5 mm cortical or a 6.5 mm cancellous screw inserted; screw pullout tests were performed at a rate of 0.04 mm/s until screw or bone failure occurred.The bone failed in all of the tests in the diaphyseal and metaphyseal bone. The holding power for 6.5 mm cancellous screws was significantly (p <0.05) greater than for 5.5 mm cortical screws in both the diaphysis and metaphysis. There was not any difference in the holding power of screws in either the diaphysis or the metaphysis between proximal and distal screw holes.If a 4.5 mm cortical bone screw strips in MCIII diaphyseal or metaphyseal bone of foals, a 6.5 mm cancellous screw would provide greater holding power than a 5.5 mm cortical screw.In order to provide information regarding selection of a replacement screw if a 4.5 mm cortical screw is stripped, the in vitro pullout strength was determined for 5.5 mm cortical and 6.5 mm cancellous screws inserted in third metacarpal diaphyseal and metaphyseal bone of foals in which threaded 4.5 mm cortical bone screw insertion holes had been overdrilled with a 4.5 mm bit. The holding power of the 6.5 mm cancellous screw was significantly greater than the 5.5 mm cortical screw in both the diaphysis and metaphysis of foal third metacarpal bone. Thus, it appears that if a 4.5 mm cortical screw is stripped during orthopaedic surgery in foals, a 6.5 mm cancellous screw would provide superior holding power.

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The “Mixing” of Implant Systems

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1633250 ◽

1991 ◽

Vol 4 (02) ◽

pp. 38-45 ◽

Cited By ~ 1

Author(s):

F. Baumgart

Keyword(s):

Stainless Steel ◽

Additional Risk ◽

Bone Screw ◽

Application Technique ◽

Quality Controls ◽

Implant Materials ◽

Osteosynthesis Plate ◽

Potential Problems ◽

Manufacturing Procedure

SummaryThe so-called “mixing” of implants and instruments from different producers entertain certain risks.The use of standardized implant materials (e.g. stainless steel ISO 5832/1) from different producers is necessary but is not sufficient to justify the use of an osteosynthesis plate from one source and a bone screw from another.The design, dimensions, tolerances, manufacturing procedure, quality controls, and application technique of the instruments and implants also vary according to make. This can lead to damage, failure or fracture of the biomechanical system called “osteosynthesis” and hence the failure of the treatment undertaken. In the end, it is the patient who pays for these problems.Some examples also illustrate the potential problems for the staff and institutions involved.The use of a unique, consistent, well-tested, and approved set of implants and instruments is to be strongly recommended to avoid any additional risk.

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Biomechanical Comparison of Screw Versus Plate/Screw Construct for Talonavicular Fusion

Foot & Ankle International ◽

10.3113/fai.2009.0150 ◽

2009 ◽

Vol 30 (02) ◽

pp. 150-156 ◽

Cited By ~ 7

Author(s):

Shelby E. Jarrell ◽

John R. Owen ◽

Jennifer S. Wayne ◽

Robert S. Adelaar

Keyword(s):

Biomechanical Comparison

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Faculty Opinions recommendation of Biomechanical comparison between fusion of two vertebrae and implantation of an artificial intervertebral disc.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.9161.466641 ◽

2006 ◽

Author(s):

Constantin Schizas

Keyword(s):

Intervertebral Disc ◽

Artificial Intervertebral Disc ◽

Biomechanical Comparison

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Biomechanical characteristics of allogeneic cortical bone pins designed for fracture fixation

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-07-03-0026 ◽

2008 ◽

Vol 21 (02) ◽

pp. 140-146

Author(s):

M. R. Edwards ◽

S. P. James ◽

W. S. Dernell ◽

R. J. Scott ◽

A. M. Bachand ◽

...

Keyword(s):

Stainless Steel ◽

Cortical Bone ◽

Fracture Fixation ◽

Impact Testing ◽

Left Tibia ◽

Four Point Bending ◽

And Gender ◽

The Right ◽

Biomechanical Comparison ◽

Better Than

SummaryThe biomechanical characteristics of 1.2 mm diameter allogeneic cortical bone pins harvested from the canine tibia were evaluated and compared to 1.1 mm diameter stainless steel pins and 1.3 mm diameter polydioxanone (PDS) pins using impact testing and four-point bending. The biomechanical performance of allogeneic cortical bone pins using impact testing was uniform with no significant differences between sites, side, and gender. In four-point bending, cortical bone pins harvested from the left tibia (204.8 ± 77.4 N/mm) were significantly stiffer than the right tibia (123.7 ± 54.4 N/mm, P=0.0001). The site of bone pin harvest also had a significant effect on stiffness, but this was dependent on interactions with gender and side. Site C in male dogs had the highest mean stiffness in the left tibia (224.4 ± 40.4 N/mm), but lowest stiffness in the right tibia (84.9 ± 24.2 N/mm). Site A in female dogs had the highest mean stiffness in the left tibia (344.9 ± 117.4 N/mm), but lowest stiffness in the right tibia (60.8 ± 3.7 N/mm). The raw and adjusted bending properties of 1.2 mm cortical bone pins were significantly better than 1.3 mm PDS pins, but significantly worse than 1.1 mm stainless steel pins (P<0.0001). In conclusion, cortical bone pins may be suitable as an implant for fracture fixation based on initial biomechanical comparison to stainless steel and PDS pins used in clinical practice.

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