scholarly journals Local heat generation during screw insertion into diaphyseal bone: a biomechanical study on different conditions (e.g. screw type, material, mode of insertion)

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Berit Paul ◽  
Andre Frank ◽  
Michael J. Raschke ◽  
Dirk Wähnert
Keyword(s):  
Saline Solution ◽  
Standard Procedure ◽  
Local Heat ◽  
Biomechanical Study ◽  
Maximum Temperature ◽  
Cold Saline ◽  
Screw Insertion ◽  
Diaphyseal Bone ◽  
Femur Diaphysis ◽  
Two Parameters

Abstract Background The implantation of screws is a standard procedure in musculoskeletal surgery. Heat can induce thermal osteonecrosis, damage the bone and lead to secondary problems like implant loosening and secondary fractures. The aim of this study was to investigate whether screw insertion generates temperatures that can cause osteonecrosis. Methods We measured the temperature of twenty human femur diaphysis in a total of 120 measurements, while screws of different material (stainless steel and titanium alloy) and different design (locking and cortex screw) were inserted in three different screwing modes (manual vs. machine screwing at full and reduced rotational speed) with 6 thermocouples (3 cis and 3 trans cortex). Each was placed at a depth of 2 mm with a distance of 1.5 mm from the outer surface of the screw. Results The screw design (cortical > locking), the site of measurement (trans-cortex > cis-cortex) and the type of screw insertion (hand insertion > machine insertion) have an influence on the increase in bone temperature. The screw material (steel > titanium), the site of measurement (trans-cortex > cis-cortex) and the type of screw insertion (machine insertion > hand insertion) have an influence on the time needed to cool below critical temperature values. The combination of the two parameters (maximum temperature and cooling time), which is particularly critical for osteonecrosis, is found only at the trans-cortex. Conclusion Inserting a screw hast the potential to increase the temperature of the surrounding bone tissue above critical values and therefore can induce osteonecrosis. The trans-cortex is the critical area for the development of temperatures above the osteonecrosis threshold, making effective cooling by irrigation difficult. It would be conceivable to cool the borehole with cold saline solution before inserting the screw or to cool the screw in cold saline solution. If possible, insertion by hand should be considered.

scholarly journals Iliac Artery Aneurysm Repair with Preservation of a Single Ectopic Pelvic Kidney

2015 ◽  
Vol 42 (1) ◽  
pp. 61-62
Author(s):  
Aurelio Sarralde ◽  
Carolina Perez-Negueruela ◽  
José M. Bernal
Keyword(s):  
Renal Artery ◽  
Iliac Artery ◽  
Saline Solution ◽  
Bypass Graft ◽  
Artery Aneurysm ◽  
Systemic Circulation ◽  
Pelvic Kidney ◽  
Iliac Artery Aneurysm ◽  
Cold Saline ◽  
One Year

An ultrasonographic study in a 60-year-old man incidentally detected an iliac artery aneurysm that gave rise to the renal artery of a single ectopic pelvic kidney. Renal-preservation solution could not be used during surgery, because the unclamped renal vein would have enabled the solution to enter the systemic circulation. Therefore, cold saline solution was infused through the renal ostium, and the kidney was maintained under cold saline immersion. We performed aortoiliac bypass and then implanted the renal artery into the bypass graft. Postoperatively, the patient's serum creatinine level increased; after one year, his renal function was normal. We discuss our use of cold saline solution for renal preservation.

INTRATHECAL COLD SALINE SOLUTION

1972 ◽  
Vol 16 (1) ◽  
pp. 4???5
Author(s):  
J. R. COLLINS ◽  
E. P. JURAS ◽  
R. J. VAN HOUTEN ◽  
L. SPRUELL
Keyword(s):  
Saline Solution ◽  
Cold Saline

scholarly journals Conventional versus helical blade screw insertion following the removal of the femoral head screw: a biomechanical evaluation using trochanteric gamma 3 locking nail versus PFN antirotation

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hong Man Cho ◽  
Kwang Min Park ◽  
Tae Gon Jung ◽  
Ji Yeon Park ◽  
Young Lee
Keyword(s):  
Experimental Models ◽  
Biomechanical Study ◽  
Original Model ◽  
Screw Insertion ◽  
Rotational Strength ◽  
Helical Blade ◽  
Locking Nail ◽  
Biomechanical Evaluation ◽  
Hip Screw ◽  
Rotational Strengths

Abstract Objective When a hip screw needs to be changed, choosing between the conventional (C-type) and helical blade (H-type) types is difficult. In this biomechanical study, we compared these two screw types relative to the type of the initial screw used. Methods C- or H-type screws were inserted (leading screw) in three types of polyurethane bone models (Sawbone, Pacific Research Laboratories, Inc., Washington, USA: 130 × 180 × 40 mm) of different bone mineral densities (pounds per cubic feet [PCF] 5, 80 kg/m3; PCF 10, 160 kg/m3; and PCF 15, 240 kg/m3), and then successively or alternately inserted (following screw) after the leading screw removal. An original model (original C and H) of a leading screw without removal was created as a control. The strengths of resistance to pullout (PO) and rotational stress were measured. For each experimental condition, there were 30 experimental models. Results The original C screw was superior in PO strength, and the original H-type screw was superior in rotational strength. When the C- or H-type screw was the leading screw, using the C-type screw again as the following screw (C1-C2, H1-C2) showed the greatest resistance to PO, and using the H-type screw as the following screw (C1-H2, H1-H2) showed superior resistance to rotational strength. However, the rotational strength of the C2 screw decreased by more than 50% compared with that of the original C screw. Moreover, the PO and rotational strengths of the H2 screw decreased to less than 30% overall compared with those of the original H screw. Conclusion The H-type screw should be used for second-time screw insertion procedures in cases where it is difficult to choose between PO and rotational strengths.

The influence of pasture distribution and temperature on habitat selection by feral pigs in a semi-arid environment

1998 ◽  
Vol 25 (5) ◽  
pp. 547 ◽  
Author(s):  
Nick Dexter
Keyword(s):  
High Temperature ◽  
High Temperatures ◽  
Radio Telemetry ◽  
Arid Environment ◽  
Food Distribution ◽  
Maximum Temperature ◽  
Feral Pigs ◽  
North West ◽  
Hot Weather ◽  
Two Parameters

The two parameters believed to influence habitat utilisation by feral pigs and wild boar (Sus scrofa) are protection from high temperatures and distribution of food. However, whether there is an interaction between these parameters is unknown. To examine the influence of high temperature on habitat utilisation, the use of four rangeland habitats (shrubland, woodland, riverine woodland, and ephemeral swamps) by feral pigs in north-west New South Wales, Australia, was measured by radio-telemetry during and after a drought. In each habitat, protection from high temperature was indexed once by vegetation cover, at three strata, while over the course of the study, food distribution was indexed by estimating pasture biomass in each habitat. Riverine woodland provided the most shelter from high temperature, followed by woodland, shrubland and ephemeral swamps. On average, ephemeral swamps had the highest pasture biomass, followed by riverine woodland, shrubland and woodland. The amount of pasture in each habitat increased after the drought but changed at different rates. During autumn, spring and summer feral pigs preferred riverine woodland but in winter shrubland was preferred. Multivariate regression indicated that habitat utilisation was significantly influenced by pasture biomass in shrubland and mean maximum temperature in the study area. The results suggest that feral pigs are restricted by high temperatures to more shady habitats during hot weather but when the constraint of high temperature is relaxed they distribute themselves more according to the availability of food.

PEDICLE SCREW CONVERGENCE IMPACT ON THE STABILITY OF TRANSPEDICULAR FIXATION SPINE MODEL IN CYCLIC LOADING: BIOMECHANICAL STUDY

2015 ◽  
Vol 15 (05) ◽  
pp. 1550078
Author(s):  
JOSEF VCELAK ◽  
PETR TICHÝ ◽  
TOMÁŠ BOUDA ◽  
JIŘÍ CHOMIAK ◽  
LADISLAV TÓTH
Keyword(s):  
Cyclic Loading ◽  
Biomechanical Study ◽  
Testing System ◽  
Structural Failure ◽  
Screw Insertion ◽  
Transpedicular Fixation ◽  
Measurement Results ◽  
Spine Model ◽  
The Stability ◽  
Cell Data

The principle of this study is experimental measurement and description of behavior of transpedicular fixation during cyclic loading due to convergence of screw insertion. Investigations were made of three configurations of assemblies of posterior stabliization with converging screws at 0°, 20° and 40°. The experiment was inspired ASTM Standard F1717 and modified to minimize the effect of other parameters. The MTS 858.2 Mini Bionix testing system was used during the experiment, in conjunction with the Interface 1010ACK load cell. Data processing and analysis were carried out by Matlab R 20102b, MathWorks. The probed assemblies were cyclically loaded until structural failure occurred, always at the screwbone (or PUR block) interface, i.e., the "windshield wiper" effect. The measurement results show that while the rigidity of the assembly increases with increased convergence of transpedicular screws, they also indicate an increased initial rate of assembly damage accumulation, together with assembly failure during a reduced number of cyclic loading cycles. The mechanical behavioral study of transpedicular fixation is limited by the conditions of simplification of interpretation of complex movements and spinal pathophysiology in the attempt to minimize the effect of other parameters and exaggerated measurements.

INTRATHECAL COLD SALINE SOLUTION

1972 ◽  
Vol 16 (1) ◽  
pp. 4???5
Author(s):  
J. R. COLLINS ◽  
E. P. JURAS ◽  
R. J. VAN HOUTEN ◽  
L. SPRUELL
Keyword(s):  
Saline Solution ◽  
Cold Saline

scholarly journals Boundary Control of Embedded Heaters for Uniform Bondline Temperatures During Composite Joining

2018 ◽  
Vol 140 (9) ◽  
Author(s):  
Brandon P. Smith ◽  
Mahdi Ashrafi ◽  
Mark E. Tuttle ◽  
Santosh Devasia
Keyword(s):  
Temperature Variation ◽  
Electrical Power ◽  
High Strength ◽  
Local Heat ◽  
Heat Sinks ◽  
Maximum Temperature ◽  
Lap Joint ◽  
Material Parameters ◽  
Single Lap Joint ◽  
Out Of Autoclave

This paper investigates an out-of-autoclave (OoA), embedded-resistive heating method to precisely control the bondline temperature when curing high strength adhesives for joining composite adherends. A challenge with OoA methods is that nonuniform heat loss, e.g., due to substructures that act as local heat sinks, can lead to nonuniform temperatures in the bondline, which in turn, can result in uneven curing, residual stresses, and potentially weak joints. The main contribution of this work is to apply a voltage pattern at the boundary of the embedded heater to control the distribution of the electrical power at the interior bondline, and thereby reduce temperature variations. Additionally, this work devises an empirical model (that can be applied when material parameters and models are not readily available) to predict the desired power generation, and to design the embedded heater and voltage pattern that minimizes the bondline temperature variation. The technique is demonstrated experimentally for bonding a single-lap joint, and the maximum temperature variation in the bond area was reduced by five times from 31.6 °C to 6.0 °C.

scholarly journals Endoscopic Removal of Two Esophageal Over-The-Scope Clips with Cold Saline Solution Technique

2018 ◽  
Vol 26 (1) ◽  
pp. 73-74 ◽  
Author(s):  
Marta Rocha ◽  
Ricardo Küttner Magalhães ◽  
Luís Maia ◽  
Teresa Moreira ◽  
Sílvia Barrias ◽  
...  
Keyword(s):  
Saline Solution ◽  
Solution Technique ◽  
Endoscopic Removal ◽  
Cold Saline
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