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1.
Sci Rep ; 13(1): 6234, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069203

RESUMO

Bone drilling is a universal procedure in orthopaedics for fracture fixation, installing implants, or reconstructive surgery. Surgical drills are subjected to wear caused by their repeated use, thermal fatigue, irrigation with saline solution, and sterilization process. Wear of the cutting edges of a drill bit (worn drill) is detrimental for bone tissues and can seriously affect its performance. The aim of this study is to move closer to minimally invasive surgical procedures in bones by investigating the effect of wear of surgical drill bits on their performance. The surface quality of the drill was found to influence the bone temperature, the axial force, the torque and the extent of biological damage around the drilling region. Worn drill produced heat above the threshold level related to thermal necrosis at a depth equal to the wall thickness of an adult human bone. Statistical analysis showed that a sharp drill bit, in combination with a medium drilling speed and drilling at shallow depth, was favourable for safe drilling in bone. This study also suggests the further research on establishing a relationship between surface integrity of a surgical drill bit and irreversible damage that it can induce in delicate tissues of bone using different drill sizes as well as drilling parameters and conditions.


Assuntos
Osso e Ossos , Temperatura Alta , Humanos , Desenho de Equipamento , Osso e Ossos/cirurgia , Temperatura , Osteotomia
2.
Life (Basel) ; 13(3)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36983955

RESUMO

BACKGROUND: Improved chemotherapy and radiotherapy treatment protocols, fortunately, increased the rates of cancer survivors over the years. However, these treatments may result in infertility or subfertility. Oncologists are considered the gateway for knowledge about cancer and its treatments' effects. Several studies showed that many oncologists do not discuss fertility preservation with their patients. This study aimed to explore the perspective of oncologists in Oman on fertility preservation. METHODS: A cross-sectional study of physicians and surgeons dealing with patients with cancer was conducted from June 2021 to December 2021. A standardized and validated questionnaire was used to collect data. RESULTS: Participants reported that they are knowledgeable about sperm cryopreservation and gonadotropin-releasing hormone agonists use but not other methods of fertility preservation. About 94% of the participants reported that they need more knowledge about fertility preservation. More than half of the participants had never encountered cancer patients who used ovarian cryopreservation, testicular tissue cryopreservation, in vitro fertilization with embryo cryopreservation and oocyte cryopreservation. The majority (78%) agreed that discussing fertility preservation with newly diagnosed cancer patients is a high priority. CONCLUSIONS: Oncologists in Oman are supportive of fertility preservation. The lack of knowledge and unavailability of well-structured fertility preservation services in Oman hinders the initiation of fertility preservation discussions.

3.
Sultan Qaboos Univ Med J ; 21(2): e297-e301, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34221479

RESUMO

OBJECTIVES: Bone failure due to avascular necrosis (AVN) is a complex pathological phenomenon. Analysis of molecular changes in the bone matrix may help to shed light on the disease process and guide management. This study aimed to explore changes in bone quality and structural damage caused by sickle cell disease (SCD)-induced AVN using Raman spectroscopy. METHODS: A total of 10 necrotic femoral heads were obtained from seven SCD patients who underwent total hip replacements. The femoral heads were cut in half and scanned using Raman spectroscopy in correlation with preoperative magnetic resonance imaging to identify necrotic and healthy control areas. Subsequently, samples were examined to determine changes in bone mineralisation, crystallinity, carbonate content, collagen cross-linking and mineral and collagen fibril orientation. RESULTS: Significant changes were observed in bone mineral content, mineral-to-organic content and collagen fibril orientation in necrotic compared to control areas (P ≤0.050). CONCLUSION: The necrotic samples displayed severe structural damage and loss of mineral and organic contents. Similar Raman signals have been reported in other metabolic bone diseases such as osteoporosis, thereby potentially supporting the use of medical treatment in AVN to promote bone quality.


Assuntos
Anemia Falciforme/complicações , Necrose da Cabeça do Fêmur/patologia , Análise Espectral Raman/métodos , Anemia Falciforme/terapia , Densidade Óssea , Remodelação Óssea , Calcificação Fisiológica , Matriz Extracelular , Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/induzido quimicamente , Necrose da Cabeça do Fêmur/cirurgia , Humanos , Necrose/induzido quimicamente , Necrose/patologia , Necrose/cirurgia
4.
Arthrosc Sports Med Rehabil ; 3(6): e1835-e1842, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34977638

RESUMO

PURPOSE: To report the functional and radiologic outcomes of meniscal repair healing in a cohort of patients with a high demand for loaded extreme flexion angles after undergoing meniscal repair. METHODS: We performed a retrospective clinical and radiologic evaluation of patients who perform extreme knee flexion activities on a daily basis at a minimum follow-up of 2 years after meniscal repair. International Knee Documentation Committee, Lysholm, and Tegner scores were obtained, and clinical examinations and radiologic (magnetic resonance imaging and radiography) evaluations were performed. RESULTS: Of 47 eligible patients, 39 patients (40 knees) were available for review with an average follow-up time of 5 years (range, 2-9 years). The average age was 26.7 years (range, 19-39 years); 38 patients were men. The average time from injury to surgery was 20.9 months (range, 3 days to 120 months). Associated anterior cruciate ligament injury was present in 31 knees, but only 20 underwent simultaneous anterior cruciate ligament surgery. The mean International Knee Documentation Committee score was 88.9 (range, 53-99). The mean Lysholm score was 90.9 (range, 48-100). The mean Tegner activity level dropped from 6.18 before injury to 5.51 at the time of evaluation. According to the Barrett criteria for clinical outcomes, complete healing was observed in 29 of 40 knees (72.5%). There was a statistically significant correlation between the functional outcomes and the clinical outcomes (P = .008). On magnetic resonance imaging, 22 of 38 knees (57.9%) showed completely healed menisci. CONCLUSIONS: The results of this study suggest that loaded deep knee flexion may be safe after a period of restricted rehabilitation, and clinical and radiologic tissue healing is independent of the overall functional outcome. LEVEL OF EVIDENCE: Level IV, case series with subgroup analysis.

5.
Strategies Trauma Limb Reconstr ; 16(3): 127-131, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35111250

RESUMO

BACKGROUND: Isolation of the causal microorganisms in osteomyelitis presents a major challenge for treating clinicians. Several methods have been proposed to rapidly and accurately identify microorganisms. There has been an increasing interest in using Raman spectroscopy in the field of microbial detection and characterisation. This paper explores the use of Raman spectroscopy identification as one of the most difficult-to-isolate microorganisms causing osteomyelitis. METHODS AND RESULTS: Fresh healthy human bone samples were collected from patients undergoing a total knee replacement. These samples were then inoculated with fresh overnight Pseudomonas aeruginosa (PAO) cultures. Bacteria growth and bone ultrastructural changes were monitored over a period of 6 weeks. The experiment demonstrated ultrastructural bony destruction caused by osteolytic PAO secretions. Raman-specific spectral signatures related to the cellular membranes of PAO structures were spotted indicating survival of bacteria on the bone surface. CONCLUSION: This study showed the promising ability of Raman spectroscopy to identify the presence of bacteria on the surface of inoculated bone samples over time. It was able to detect the osteolytic activity of the bacteria as well as ultrastructure specific to PAO virulence. This method may have a role as an aid to existing diagnostic methods for fast and accurate bacterial identification in bone infection. HOW TO CITE THIS ARTICLE: Al Ghaithi A, Al Bimani A, Al Maskari S. Investigating the Growth of Pseudomonas aeruginosa and Its Influence on Osteolysis in Human Bone: An In Vitro Study. Strategies Trauma Limb Reconstr 2021;16(3):127-131.

6.
Biomed Mater Eng ; 31(5): 269-277, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986649

RESUMO

BACKGROUND: Drilling is a well-known mechanical operation performed for fixing fracture at required locations in bone. The process may produce mechanical and thermal alterations in the structure of the bone and surrounding tissues leading to irreversible damage known as osteonecrosis. OBJECTIVE: The main purpose of this study was to measure the level of biological damage in bone when a drill assisted by low and high levels of vibrations is penetrated into bone tissue. METHODS: Histopathology examination of sections of bones has been performed after drilling the bone using a range of vibrational frequency and rotational speed imposed on the drill with and without supply of saline for cooling. RESULTS: Cell damage in bone was caused by the combined effect of drill speed and frequency of vibrations. Histopathology examination revealed more damage to bone cells when a frequency higher than 20 kHz was used in the absence of cooling. Cooling the drilling region helped minimize cell damage more at a shallow depth of drilling compared to deep drilling in the cortex of cortical bone. The contribution of cooling in minimizing cell damage was higher with a lower drill speed and frequency compared to a higher drill speed and frequency. CONCLUSION: Vibrational drilling using a lower drill speed and frequency below 25 kHz in the presence of cooling was found to be favorable for safe and efficient drilling in bone.


Assuntos
Osso e Ossos , Procedimentos Ortopédicos , Osso Cortical/cirurgia , Temperatura Alta , Humanos , Osteonecrose , Vibração
7.
Biomed Tech (Berl) ; 65(1): 113-120, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31437122

RESUMO

Bone drilling is a well-known process in operative fracture treatment and reconstructive surgery. The cutting ability of the drill is lost when used for multiple times. In this study, the effect of different levels of drill wear on bone temperature, drilling force, torque, delamination around the drilling region and surface roughness of the hole was investigated using a series of experiments. Experimental results demonstrated that the wear of the drill is strongly related to the drilling force, torque, temperature and surface roughness of the drilled hole. Statistical analysis was performed to find the effect of various factors on multiple response variables in the bone drilling process. The favorable conditions for bone drilling are obtained when feed rate, drill speed and the roughness of the cutting edge of the drill were fixed at 30 mm, 2000 rpm and up to 2 mm, respectively. Further, analysis of variance (ANOVA) was performed to determine the factor with a significant impact on the response variables. F-test and p-value indicated that the feed rate had the highest effect on grey relational grade followed by the roughness of the drill. This study suggests that the sharp drill along with controlled drilling speed and feed rate may be used for safe and efficient surgical drilling in bone.


Assuntos
Osso e Ossos/fisiologia , Osso e Ossos/cirurgia , Desenho de Equipamento , Temperatura Alta/efeitos adversos , Temperatura , Torque
8.
Med Eng Phys ; 67: 78-87, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30981608

RESUMO

Drilling is a common surgical procedure for fracture treatment and reconstruction in multiple surgical fields, including orthopaedics, neurology, and dentistry. Drilling delicate tissue (such as bone) with a hard metallic tool is considered notorious for inducing mechanical and thermal damage, which can adversely affect osseointegration and may weaken the bond between the bone and implant, or other fixative devices anchoring the bone. The aim of this study is to explore the benefits of vibrational drilling (VD) in overcoming the complications associated with conventional drilling (CD). Drilling tests were performed on fresh cortical bone with the intention of investigating the effect of a range of frequencies, in combination with drilling speed and feed rate, on biological damage around the drilling region using histological sections of skeletally mature bone. The study examined the most influential factors and optimal combination of parameters for safe and efficient drilling in bone. Results from Taguchi grey relational analysis showed that a lower drilling speed and feed rate combined with a frequency of 20 kHz were favourable parameters for safe drilling in bone. Accordingly, VD using controlled parameters may be an alternative to CD in bone surgical procedures.


Assuntos
Fêmur/citologia , Fêmur/cirurgia , Procedimentos Ortopédicos/métodos , Vibração , Animais , Bovinos , Fenômenos Mecânicos , Temperatura , Torque
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