Mechanics & bone bio Flashcards
Gremley, vet surg 2023
The effect of grip location on Kirschner wire bend characteristics: An in vitro study
-what grip location minimised bend angle and radius for…
a) 0.9mmm k-wire
b) 1.1mm k-wire
c) 1.6mm k-wire
a) 2cm for 0.9mm
b) 3cm for 1.1mm
c) 3cm for 1.6m
torque is not minimised at these locations
Deprey vet surg 2022
Mechanical evaluation of a novel angle-stable interlocking nail in a gap fracture model
-difference between surgX nail and LCP in maximal deformation in torsion?
no difference in maximal deformation in torsion
nail beat the LCP in every other test
Paulick, vet surg 2021
Ex vivo comparison of lateral plate repairs of experimentaloblique ilial fractures in cats
which implants were less resistant to cyclic loading?
a) DCP
b) LCP
c) Fixin locking plate
d) ALPS-5
e) ALPS-6
The DCP and ALPS-5 constructs are less resistant to cyclic loading
locking constructs failed by bone splicing, DCP by pull out
Murro, vet surg 2021
Stiffness of a type II external skeletal fixator and locking compression plate in a fracture gap model
-Which construct was stiffer in….
a) ML bending
b) Cr-ca bending
c) compression
A) ESF stiffer ML
b) no difference Cr-ca
c) ESF stiffer compression
Marturello vet surg 2020
Mechanical comparison of two small interlocking nails in torsion using a feline bone surrogate
-ILOC 4, targon nail and LCP compared.
which construct had the highest angular deformation?
-where did all models fail following explant?
Targon had highest AD due to construct slipping
all models failed at innermost hole
[iloc had smallest AD and torsional compliance of all constructs]
Thompson vet surg 2020
Influence of wire configuration on resistance to fragment distraction of tension bands placed in a greater trochanteric osteotomy model
In which of the single twist or double twist constructs was the initial tension and load to 2mm displacement lower in?
**what was the most stable configuration? **
-what factor was correlated with failure load?
-Figure of 8 one twist lower initial tension and load to 2mm displacement compared to two twist
-double loop twist - 2.3-3.5x greater initial tension and maintaining greater residual tension under cyclic load, resisting 2-2.4x greater load before failure at 2mm.
- initial tension
Gallagher, vet surg 2019
Effects of short- and long-term administration of nonsteroidal anti-inflammatory drugs on osteotomy healing in dogs
-what was effect of 8 weeks carprofen compared to no carprofen?
8 weeks carprofen had slower radiographic healing and decreased stiffness and maximum stress than dogs that received no carprofen.
no difference between no carprofen and 2 weeks carprofen,.
Palierne, vcot 2022
Biomechanical Comparison of Use of Two Screws versus Three Screws Per Fragment with Locking Plate Constructs under Cyclic Loading in Compression in a Fracture Gap Model
-what effect did omission of the third innermost locking screw have?
In compression, omitting third innermost screw:
13% reduction in the number of cycles to failure
24% reduction of the load withstood by the plate before plastic deformation
[note, this is crap, the working length changes]
Miller, VCOT 2024
Mechanical Testing of Sliding on Pivot-Locking Clamp (SOP-LC) Fracture Repair System in Four-Point Bending and Torsion
-what was the effect of contouring the rod?
-effect of clamps on alternating sides?
No difference between contour and no contour on rod
Constructs with clamps on a single side had a significantly higher yield
load, yield displacement and bending strength
constructs with alternating clamps had a significantly higher initial torsional stiffness
Park, VCOT 2022
Effect of Bidirectional Insertion of External Skeletal Fixation Pins on Axial Pullout Strength in Canine Cadaveric Bone
which type of pin had the highest pull out strength?
which method of pin placement had highest pull out strength?
-positive profile pin had highest pull out strength
-tapered run out and positive profile pins had highest pull out strength with unidirectional insertion (no difference for negative threaded pin)
Schrock, VCOT 2022
Outcomes and Complications Associated with Acute Gunshot Fractures in Cats and Dogs
-what number had poor outcome?
-what factor associated with poor outcome?
-20/37 (54%) poor outcome
-extensive soft tissue trauma at fracture site associated with poor outcome
Bird, VCOT 2021
Biomechanical Comparison of a Notched Head Locking T-Plate and a Straight Locking Compression Plate in a Juxta-Articular Fracture Model
which construct was stiffer and lower plate strain?
what was impact of working length?
LCP with 2 screws distal was stiffer and lower plate strain than notched T plate with 3 screws in short fragment.
shorter working length stiffer with lower plate strain in both
Jung, VCOT 2021
Effect of screw insertion torque on mechanical properties of a hybrid polyaxial locking system
ARIX system (jeil medical)
-what failure types were seen?
-at which insertion torque did insertion angle impact screw push out?
-cold welding and plate deformation
-An angled screw with insertion torque at 0.8Nm impacted screw push out resistance. Angling screw did not matter at 0.2, 0.4, 0.6Nm insertion torques.
Insertion torque 1Nm resulted in screw head stripping and plate hole deformation
Marturello, VCOT 2021
Evaluation of a feline bone surrogate and in vitro mechanical comparison of small interlocking nail systems in mediolateral bending
(compared iloc, targon, LCP)
-which construct had the smallest bending compliance?
-which construct had the largest bending compliance?
-which explanted construct had the lowest failure moment?
–iloc 4 smallest
-LCP 2.0 largest
-targon
Kaczmarek VCOT 2020
Mechanical Performance of a Polyaxial Locking Plate and the Influence of Screw Angulation in a Fracture Gap Model
-on average, how much weaker were PLS plates than LCP?
-braun system, partially threaded holes, stainless steel, 15 degrees angulation permitted.
30% weaker
