scholarly journals Inventive Methods Used to Study and Control Thermal Necrosis: A Review

2020 ◽  
Author(s):  
Rajesh V Dahibhate ◽  
Santosh B Jaju ◽  
Rajendra I Sarode
Keyword(s):  
Cell Damage ◽  
Secondary Infection ◽  
Circular Cross Section ◽  
Bone Surface ◽  
Bone Drilling ◽  
Thermal Necrosis ◽  
Screw Insertion ◽  
Drilling Site ◽  
And Control ◽  
Drill Tool

Orthopedic surgeries use screw and plate fixations. Bone drilling is performed for smooth and minimum damage to bone surface during screw insertion. Bone drilling creates a hole with circular cross-section. This process involves cutting and material removal with a helical drill tool. Heat is generated at the drilling site due to cutting, shearing of bone material by drill tool and friction between drill tool and bone surface. Previous research studies found that if temperature at drilling site reaches 47°C and remains the same for one minute, irreversible cell damage i.e. thermal necrosis can occur. Thermal necrosis causes ring sequestrum around the pin; this leads to a vicious cycle involving secondary infection, discharge and pin loosening. This postoperative complication can only be rectified by removal of pin and sequestrum, curettage of the tract and pin replacement and so thermal necrosis- the root cause must be avoided and attended very seriously. To avoid thermal necrosis, postoperative complications and delay in patient rehabilitation, researchers are studying bone drilling in detail. In this review paper, a discussion is made on different innovative methods that are turning points in the study of thermal necrosis and the latest technologically improved equipment devised by researchers. These inventive methods have used experimental set ups, software-based simulations and training programs. The author also conducted experiments on female goat rib bone and based on these observations an improved drilling machine is suggested.

scholarly journals Bone drilling with internal gas cooling: Experimental and statistical investigation of the effect of cooling with CO2 on reduction of temperature rise due to drill bit wear

2021 ◽  
Vol 16 (2) ◽  
pp. 199-211
Author(s):  
E. Shakouri ◽  
H. Haghighi Hassanalideh ◽  
S. Fotuhi
Keyword(s):  
Temperature Rise ◽  
Drill Bit ◽  
Bone Drilling ◽  
Thermal Necrosis ◽  
Allowable Limit ◽  
Cooling Method ◽  
Bit Wear ◽  
Gas Cooling ◽  
Drilling Operations ◽  
Drilling Site

Bone drilling is a major stage in immobilization of the fracture site. During bone drilling operations, the temperature may exceed the allowable limit of 47 °C, causing irrecoverable damages of thermal necrosis and seriously threatening the fracture treatment. One of the parameters affecting the temperature rise of the drilling site is the frequency of applying the drill bit and its extent of wear. The present study attempted to mitigate the effect of drill bit wear on the bone temperature rise through the internal gas cooling method via CO2 and to reduce the risk of incidence of thermal necrosis. To this end, drilling tests were conducted at three rotational speeds 1000, 2000, and 3000 r·min-1 in two states of without cooling and with internal gas cooling by CO2 through an internal coolant carbide drill bit, along with six drill bit states (new, used 10, 20, 30, 40, and 50 times) on a bovine femur bone. The results indicated that in the internal gas cooling state, as the number of drill bit applications increased from the new state to more than 50 times, the temperature of the hole site increased on average by ΔT = 2-3 °C (n = 1000 r·min-1), ΔT = 5-8 °C (n = 2000 r·min-1), and ΔT = 5-7 °C (n = 3000 r·min-1). Furthermore, the internal gas cooling method was able to significantly reduce the effect of the drill bit wear on the temperature rise of the drilling site and to resolve the risk of incidence of thermal necrosis regardless of the process parameters for drilling operations.

scholarly journals Effect of fruit-juice on spermatozoa viability and lipid peroxidation of Red Sokoto bucks during liquid storage

2021 ◽  
Vol 41 (1) ◽  
pp. 16-27
Author(s):  
J. O. Daramola ◽  
T. A. Sorongbe ◽  
O. M. Onagbesan ◽  
A. V. Jegede ◽  
A. O. Ladokun ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Cell Damage ◽  
Egg Yolk ◽  
Protective Effects ◽  
Sperm Viability ◽  
Progressive Motility ◽  
Liquid Storage ◽  
Watermelon Juice ◽  
And Control

Antioxidants are linked with sperm viability because of their protective effects against cell damage during preservation. In order to enhance the life span of refrigerated buck semen, this study was carried out to determine the effect of fruit-rich antioxidants on spermatozoa viability and lipid peroxidation (LPO) of buck semen during liquid storage. Pooled semen from five Red Sokoto bucks was diluted with Tris-egg yolk based extender and supplemented each with juices from pawpaw tomato and watermelon at 0, 2.5, 5, 7.5 and 10/ 100 ml respectively. Following dilution, the semen samples were assessed subjectively after in vitro storage at 5°C for 24, 48, 72 and 96 hours as regards sperm motility, abnormalities, and acrosome status using a phase-contrast microscope. The concentration of malondialdehyde (MDA) as indices of lipid peroxidation (LPO) in the stored semen was measured in thiobarbituric acid reactive substances (TBARS) at 24, 48, 72 and 96 hours. The results showed highest progressive motility in watermelon juice at 2.5% (P<0.05) during the first 24 hours of storage while the lowest progressive motility was recorded at various levels of pawpaw juice (P<0.05). After 48 hours of storage, extender supplemented with watermelon and tomato juices had better progressive motility compared to control except 7.5% and 10%% of tomato juice (P<0.05). Irrespective of level of juice in the extender, the percentage of intact acrosome was similar among the various juices and control. The results showed that spermatozoa extended with watermelon juice had the lowest (P<0.05) percentage abnormality compared to other extenders at 24, 48, 72 and 96 hours of storage. Higher (P<0.05) percent spermatozoa abnormality compared to other fruit juices and control was observed at 72 and 96 hours of storage in spermatozoa extended with pawpaw juice. Significant reductions of MDA concentrations were achieved by addition of fruit-rich antioxidants to Tris-egg yolk based extender during the first 72 hours and the reduction was much pronounced in extender supplemented with pawpaw juice compared to control (P<0.05). The findings reveal that fruit-rich antioxidants from watermelon and tomato have protective ability to maintain sperm viability and to reduce concentration MDA of buck semen during liquid storage.

EXPERIMENTAL STUDY ON THE EFFECT OF DRILL QUALITY ON BONE TEMPERATURE IN DRILLING

2018 ◽  
Vol 30 (02) ◽  
pp. 1850018 ◽  
Author(s):  
Khurshid Alam ◽  
Syed Husain Imran ◽  
Abdullah Al-Shabibi ◽  
Mojtaba Ghodsi ◽  
Vadim Silberschmidth
Keyword(s):  
Experimental Study ◽  
Bone Tissue ◽  
Femoral Shaft ◽  
Tissue Temperature ◽  
Bone Drilling ◽  
Thermal Necrosis ◽  
Bone Material ◽  
Rate Of Penetration ◽  
Lower Temperature ◽  
Drilling Conditions

Bone drilling is widely performed in orthopedics for fixation and reconstruction of bone. In bone drilling, a hard metallic drill penetrates into the bone tissue which may cause trauma. Shear deformation of the bone material and friction between the drill and bone may induce elevated temperature in bone tissue. Temperature above a certain level may seriously harm the tissue, leading to several postoperative complications. The purpose of the current study is to measure and compare temperature in bone drilling using sharp and worn drill. Drilling tests were performed on cortical bone obtained from femoral shaft of a cow. A parametric study was conducted to quantify bone temperature using a range of drilling speeds and feed rates using drills having sharp and worn cutting edges with and without cooling environment. The temperature was measured using thermocouples, and wear of the cutting edges of the drill was measured using a scanning profilometer. Experimental results demonstrated lower temperature in bone using a sharp drill compared with a worn drill for similar drilling conditions. The bone temperature was found to rise with drill rotational speed, rate of penetration and size of the drill with and without cooling. Blunt drills were found more crucial for inducing thermal necrosis in bone.

scholarly journals Modified iliac spine wafer osteotomy for exposure during Bernese periacetabular osteotomy

2019 ◽  
Vol 6 (4) ◽  
pp. 421-425 ◽  
Author(s):  
Linsen T Samuel ◽  
Mohammed Munim ◽  
Alexander J Acuña ◽  
Assem A Sultan ◽  
Atul F Kamath
Keyword(s):  
Hip Dysplasia ◽  
Screw Fixation ◽  
Periacetabular Osteotomy ◽  
Technical Note ◽  
Suture Fixation ◽  
Iliac Wing ◽  
Screw Insertion ◽  
Femoral Cutaneous Nerve ◽  
Osteotomy Technique ◽  
And Control

Abstract The Bernese periacetabular osteotomy (PAO) is a well-established procedure for the management of symptomatic hip dysplasia. The associated Smith–Petersen exposure offers excellent visualization of the acetabulum and control of acetabular osteotomy and mobilization. The traditional exposure of the true pelvis involves osteotomy of the iliac wing in order to mobilize the sartorial and inguinal ligament insertion. However, full osteotomy of the iliac spine may necessitate screw fixation if a relatively large segment of bone is included. A known complication with screw fixation of the iliac wing osteotomy involves failure of fixation and screw back out. Moreover, the screw may irritate the patient even in the setting of adequate fixation. A larger osteotomy may also injure the lateral femoral cutaneous nerve (LFCN) as it travels near the anterior–superior spine. To minimize the risk of these potential complications, a wafer osteotomy may be used to develop a sleeve of tissue involving the sartorial insertion. This sleeve also mobilizes the entirety of the LFCN medially and affords protection throughout the procedure. Furthermore, the wafer osteotomy may be re-fixed to the stable pelvis during closure with simple heavy suture fixation alone, avoiding screw insertion or associated removal. Because only a wafer or bone is taken during the spine osteotomy, more bone is available at the anterior–superior iliac spine for fixation of the mobile fragment after repositioning. In this technical note, we describe the wafer osteotomy technique in further detail.

Automatic Bone Drilling in Orthopedic Surgery - Overcoming of the Drill Bit Bending at the Second Cortex

2014 ◽  
Vol 664 ◽  
pp. 419-422 ◽  
Author(s):  
George Boiadjiev ◽  
Kamen Delchev ◽  
Tony Boiadjiev ◽  
Kazimir Zagurski ◽  
Rumen Kastelov
Keyword(s):  
Orthopedic Surgery ◽  
Force Control ◽  
Thrust Force ◽  
Screw Fixation ◽  
Drill Bit ◽  
Bone Surface ◽  
Active Force ◽  
Bone Drilling ◽  
Bone Damage ◽  
Specific Shape

This paper discusses a problem appeared by drill bit bending during bone drilling in the orthopedic surgery, where precision is needed for screws to be implanted. The bone surface has a specific shape and the drill bit may slip a little along the bone before the process start, when a large thrust force is applied by hand-drilling. That could be seen and correct by the surgeon. But he can’t see inside – where the second cortex drilling starts. The drill bit bending leads to the worse screw fixation and even to the bone damage – if the drill bit stays off broken inside. To solve this problem an active force control is made by robot application. Experiments and results are presented.

Theoretical modelling of the self-tapping screw fastening process

2001 ◽  
Vol 215 (2) ◽  
pp. 135-154 ◽  
Author(s):  
L D Seneviratne ◽  
F A Ngemoh ◽  
S W E Earles ◽  
K A Althoefer
Keyword(s):  
Theoretical Model ◽  
Control Strategies ◽  
The Self ◽  
Theoretical Modelling ◽  
Insertion Torque ◽  
Monitoring And Control ◽  
Screw Insertion ◽  
Engineering Mechanics ◽  
And Control ◽  
Insertion Process

The results of a theoretical study of the self-tapping screw insertion process are presented. Fundamental concepts of engineering mechanics are employed to analyse the axial torque required to complete a general self-tapping screw insertion operation. Equations for the screw insertion torque as a function of screw, hole and material properties are presented. Experimental results for torque signature signals are compared with the predictions of the theoretical model, confirming the validity of the model. The theoretical model provides a basis for developing automated monitoring and control strategies for self-tapping screw fastenings.

scholarly journals Clinical and epidemiologic characteristics associated with dengue fever in 2011–2016 in Bang Phae district, Ratchaburi province, Thailand

2021 ◽  
Vol 15 (6) ◽  
pp. e0009513
Author(s):  
Jacqueline Kyungah Lim ◽  
Pornthep Chanthavanich ◽  
Kriengsak Limkittikul ◽  
Jung-Seok Lee ◽  
Chukiat Sirivichayakul ◽  
...  
Keyword(s):  
Secondary Infection ◽  
Implementation Strategies ◽  
Public Health Problem ◽  
Febrile Illness ◽  
Major Public Health Problem ◽  
Mild Disease ◽  
Study Results ◽  
Dengue Prevention ◽  
Febrile Episodes ◽  
And Control

Background Dengue is a major public health problem in Thailand, but data are often focused on certain dengue-endemic areas. Methods: To better understand dengue epidemiology and clinical characteristics in Thailand, a fever surveillance study was conducted among patients aged 1–55 years, who presented with non-localized febrile illness at Bang Phae Community Hospital in Ratchaburi province, Thailand from October 2011 to September 2016. Results Among 951 febrile episodes, 130 were dengue-confirmed. Individuals aged 10–14 years were mostly affected, followed by those 15–19 years-of-age, with about 15% of dengue-confirmed cases from adults 25 years and older. There were annual peaks of dengue occurrence between June-November. Most prevalent serotype in circulation was DENV-2 in 2012, DENV-3 in 2014, and DENV-4 & -3 in 2015. Among dengue cases, 65% were accurately detected using the dengue NS1 RDT. Detection rate was similar between secondary and primary dengue cases where 66% of secondary vs. 60% of primary dengue cases had positive results on the NS1 RDT. Among dengue cases, 66% were clinically diagnosed with suspected dengue or DHF, prior to lab confirmation. Dengue was positively associated with rash, headache, hematemesis and alterations to consciousness, when compared to non-dengue. Dengue patients were 10.6 times more likely to be hospitalized, compared to non-dengue cases. Among dengue cases, 95 were secondary and 35 were primary infections. There were 8 suspected DHF cases and all were identified to be secondary dengue. Secondary dengue cases were 3.5 times more likely to be hospitalized compared to primary dengue cases. Although the majority of our dengue-positive patients were secondary dengue cases, with few patients showing manifestations of DHF, our dengue cases were mostly mild disease. Even among children < 10 years-of-age, 61% had secondary infection and the rate of secondary infection increased with age. Conclusion While the majority of dengue-confirmed cases were children, almost three-quarters of dengue-confirmed cases in this study were secondary dengue. Our study results consistent with previous data from the country confirm the hyperendemic transmission of DENV in Thailand, even in the non-epidemic years. With various interventions becoming available for dengue prevention and control, including dengue vaccines, decision-making on future implementation strategies should be based on such burden of disease data.

scholarly journals Effect of Using Coolant on the Formation of Microcracks, Burr and Delamination in Bone Drilling Process

2021 ◽  
Vol 1 (1) ◽  
pp. 17-26
Author(s):  
Rusnaldy Rusnaldy ◽  
Pratama Eka Putra Sijabat ◽  
Paryanto Paryanto ◽  
Toni Prahasto
Keyword(s):  
Cortical Bone ◽  
Bone Microstructure ◽  
Initial Position ◽  
Burr Formation ◽  
Drilling Process ◽  
Bone Drilling ◽  
Screw Insertion ◽  
Bone Surgery ◽  
Drilling Temperature ◽  
The Stability

Direct approach for bone fracture treatment usually involves restoring the fractured parts to their initial position and immobilizing them with plates, screws and wires. This approach needs a bone surgery drilling to produce hole for screw insertion. But this drilling process causes mechanical damages, i.e microcracks, burr formation and delamination, that can reduce the stability of the fixation. One of the ways to minimize it is by using coolant. Moreover, it is noted that bone has anisotropic microstucture. The object of this study is to understand the effect of coolant on mechanical damages that occur in bone drilling and to understand the effect of microstructure difference on microcracks that occur in the drilled walls holes. Adult bovine bones and adult goat bones were used in this study as the specimens to represent differences in cortical bone microstructure. Five consecutive holes from the distal to the proximal in each specimen were generated using manual hand-drill (spindle speed (n) = 1000 rpm; drill bit (d) = 4 mm diameter) with the use of coolant as variation. The drilling holes then stained and observed using a microscope. As the result, it was found that the use of coolant can significantly reduce the drilling temperature. Microcracks, burr formation and delamination were found to be quite large in the drilling holes without coolant. However, there is no microcrack found in the drilling holes with coolant, there is only a small number of burr formation was found. In addition, it was found that the differences in bone microstructure affect the number and length of microcracks that occur in the wall of the hole. It can be concluded from this study that the application of coolant is very effective to reduce the drilling temperature and enhancing the quality of the hole generated by bone drilling and the higher the density of osteon in cortical bone, the easier the microcrack to initiate and propagate.

Scabies outbreak investigation among madrasahs in Sinana district, Bale Zone, Oromia, Ethiopia, May 2019

2020 ◽  
Author(s):  
Mohammed Hasen Badeso ◽  
Henok Asefa Ferede ◽  
Falaho Sani Kalil
Keyword(s):  
Secondary Infection ◽  
Public Health Problem ◽  
Signs And Symptoms ◽  
P Value ◽  
Major Public Health Problem ◽  
Travel History ◽  
Disability Adjusted Life ◽  
Life Years ◽  
Crusted Scabies ◽  
And Control

Abstract Background: Scabies is neglected parasitic disease and major public health problem worldwide, particularly in resource-poor regions including Ethiopia. It has been estimated about 300 million cases reported yearly and causes more than 1.5 million Disability Adjusted Life Years for all age. The study conducted in Ethiopia, among ‘Yekolo-Temari’ revealed 22.5% scabies prevalence. On March 9, 2019, the Sinana district surveillance office reported a scabies outbreak in five madrasahs. We investigate to determine its magnitude, identify risk factors and provide intervention and recommendation.Methods: We conducted a (1:2) unmatched case-control study. The scabies case-patient was any student of madrasahs in Sinana district with signs and symptoms consistent with scabies (superficial burrows, intense itching especially at night, generalized rash and secondary infection) from March 11 to April 30, 2019. We reviewed the line list and conducted active case finding. Participants were recruited from all madrasahs (five) proportional to the number of students in each madrasah (56 cases-patients and 111 controls) and interviewed with structured questionnaires. We use OR, P-value and 95% CI to measure the strength of association in multivariable logistic regression. Result: We identified 815 (6 crusted) scabies cases-patients (100% male) with the attack rate 143 per 1000 population (815/5,689) and no death and the mean age was 14 years (range 8-28 years). Sharing bed with scabies case (AOR=3.9, [95% CI=1.5-10.3], travel history to scabies area (AOR=3.87, [95% CI=1.19-12.56], showering more than a week interval (AOR= 2.74, [95% CI=1.04-7.21] were statistically associated with illness.Conclusion: Sharing bed with scabies case, travel history to scabies area and showering more than a week interval was associated with a high frequency of scabies infestation. All patients and contacts treated, additionally, at two madrasahs mass drug administration conducted with permethrin, and cloxacillin for secondary infection. We recommend health education about the transmission, prevention and control of scabies disease to the students.

scholarly journals Studying and approximating spatio–temporal models for epidemic spread and control

1998 ◽  
Vol 353 (1378) ◽  
pp. 2153-2162 ◽  
Author(s):  
J. A. N. Filipe ◽  
G. J. Gibson
Keyword(s):  
Control Strategies ◽  
Secondary Infection ◽  
Contact Process ◽  
Approximate Solutions ◽  
Field Approximation ◽  
Mean Field Approximation ◽  
Range Interaction ◽  
Temporal Models ◽  
Spatio Temporal ◽  
And Control

A class of simple spatio–temporal stochastic models for the spread and control of plant disease is investigated. We consider a lattice–based susceptible–infected model in which the infection of a host occurs through two distinct processes: a background infective challenge representing primary infection from external sources, and a short–range interaction representing the secondary infection of susceptibles by infectives within the population. Recent data–modelling studies have suggested that the above model may describe the spread of aphid–borne virus diseases in orchards. In addition, we extend the model to represent the effects of different control strategies involving replantation (or recovery). The Contact Process is a particular case of this model. The behaviour of the model has been studied using Cellular–Automata simulations. An alternative approach is to formulate a set of deterministic differential equations that captures the essential dynamics of the stochastic system. Approximate solutions to this set of equations, describing the time evolution over the whole parameter range, have been obtained using the pairwise approximation (PA) as well as the most commonly used mean–field approximation (MF). Comparison with simulation results shows that PA is significantly superior to MF, predicting accurately both transient and long–run, stationary behaviour over relevant parts of the parameter space. The conditions for the validity of the approximations to the present model and extensions thereof are discussed.

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