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Development and evaluation of new cementless revision acetabular components for total hip arthroplasty / type TC /
Šťastný, Eduard ; Trč, Tomáš (advisor) ; Šponer, Pavel (referee) ; Pilný, Jaroslav (referee)
Development and evaluation of new cementless revision acetabular components for total hip arthroplasty / type TC / Objective: The aim of the clinical part of the study was to introduce a new revision oval cup type TC, and evaluate its reliability and utility in revision endoprosthesis. Due to the different structure of the implant, we aimed to objectively demonstrate the remodeling of bone tissue in its vicinity. In the experimental part of the work we verified the hypothesis that the use of locking screws has an effect on the bond strength of the implant with bone tissue, and therefore on the primary stability of the acetabular component. Method: We evaluated 31 patients that underwent revision hip surgery between 2004 and 2008. The mean follow-up was 7.1 years (range 5.3 to 9.3 years, minimum 5 years after surgery). Osteointegration of the implant and remodeling of bone tissue around the implant and its ribs were evaluated by digital radiography and computed tomography, and clinical results according to Harris. The experiment was based on the execution of pull-out tests after the implantation of TC cups in cadaveric bovine pelves. We evaluated the dependence of tensile forces in the axis of the implant on extraction of the metal cup from the bone bed. Four tests were conducted with the cup fixed...
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Bone remodeling in rheumatic diseases: Bone loss in juvenile idiopathic arthritis
Brábníková Marešová, Kristýna ; Štěpán, Jan (advisor) ; Blahoš, Jaroslav (referee) ; Hrnčíř, Zbyněk (referee)
Introduction: The inflammation plays the essential role in the bone loss in juvenile idiopathic arthritis (JIA). Proinflammatory cytokines and also glucocorticoids (GCs) may activate bone resorption by osteoclasts. Simultaneously, bone formation can be attenuated, especially by inhibitors of proteins, which control the osteoblast differentiation. The aim was to verify the hypothesis that in patients with highly active JIA, reduction of bone formation via Wingless (Wnt) proteins inhibitors - Dickkopf 1 (Dkk-1) and sclerostin could be found. Except the densitometry measurements of bone and lean mass, we assessed markers of disease activity, bone metabolism and remodeling in young adult patients with JIA before and during 2 years of anti TNFα (tumour necrosis factor α) treatment, which decreases disease activity. Results: In patients with JIA before antiTNFα treatment, bone mineral density (BMD, g/cmš) was significantly reduced compared to controls. Values of BMD and body composition in JIA significantly depended on disease duration and GCs treatment. Serum concentration of sclerostin was significantly elevated in JIA compared to values in healthy controls. Values of the other monitored markers did not differ between JIA and controls. In patients with JIA, Dkk-1 correlated positively with C-reactive...
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Circadian rhythm of parathyroid hormone and bone remodeling: implication for the osteoporosis treatment with teriparatide (parathormone [1-34])
Rašková, Mária ; Zikán, Vít (advisor) ; Žofková, Ivana (referee) ; Perlík, František (referee)
Circadian rhythm of parathyroid hormone (PTH) is well documented, but its physiological role is not fully understood. In healthy individuals, biochemical markers of bone remodeling follow a similar circadian rhythm to PTH with a nocturnal rise in bone resorption and formation. The loss of PTH diurnal variation was observed not only in primary hyperparathyroidism, but also in patients with postmenopausal osteoporosis. Continuously elevated concentrations of PTH lead to excessive stimulation of bone resorption, whereas intermittent PTH administration has a strong osteoanabolic effect in patients with osteoporosis. It has not been examined whether the skeletal sensitivity to PTH action depends also on the time of its application. The aim of our study was to verify the hypothesis that the application of teriparatide (TPTD, recombinant human PTH [1-34]) at different times of the day in the context of its diurnal variability affects the physiological circadian rhythm of bone remodeling and also the bone mineral density (BMD) after the long-term TPTD treatment. Fourteen women with postmenopausal osteoporosis treated with 20 micrograms of TPTD daily, applied subcutaneously either in the morning or evening, were included in the first study. The concentration of serum C-terminal telopeptide of type I collagen...
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Serum concentration of vitamin D in patients with femoral neck fracture
Matoušková, Karolína ; Wenchich, László (advisor) ; Zikán, Vít (referee)
Vitamin D significantly affects metabolism of the bone tissue. It keeps homeostasis of calcium and phosphor and thus contributes to healthier mineralization of bones. Lack of those substances pertains to risk factors for development of osteoporosis and subsequent complications during possible downfalls and fractures. The role of vitamin D in bone disease has been increasing in recent years, but its importance in the early post-fracture period is not yet fully understood. This thesis is a prospective study of metabolism of vitamin D and its metabolites in post-operative stage of patients with femoral neck fractures. It is a basic quantitative research, where received data are analysed. Blood samples obtained from a total of 18 patients, whose blood was taken on the day of surgery and 6 weeks after surgery (± 1 week), were used as material. Resulted values of 25-OH vitamin D increased from 23,02 ± 16,02 nmol/l to 25,75 ± 16,30 nmol/l (diameter ± standard deviation). In contrast, 1,25-(OH)2 vitamin D decreased from 76,81 ± 41,84 pmol/l to 55,88 ± 26,34 pmol/l. Statistically significant results at a significance level of p≤0,05 were only observed for parathyroid hormone (PTH), with values decreasing from 6,31 ± 3,95 pmol/l to 3,96 ± 2,25 pmol/l. Vitamin D examinations in our patients showed reduced...
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Development and evaluation of new cementless revision acetabular components for total hip arthroplasty / type TC /
Šťastný, Eduard ; Trč, Tomáš (advisor) ; Šponer, Pavel (referee) ; Pilný, Jaroslav (referee)
Development and evaluation of new cementless revision acetabular components for total hip arthroplasty / type TC / Objective: The aim of the clinical part of the study was to introduce a new revision oval cup type TC, and evaluate its reliability and utility in revision endoprosthesis. Due to the different structure of the implant, we aimed to objectively demonstrate the remodeling of bone tissue in its vicinity. In the experimental part of the work we verified the hypothesis that the use of locking screws has an effect on the bond strength of the implant with bone tissue, and therefore on the primary stability of the acetabular component. Method: We evaluated 31 patients that underwent revision hip surgery between 2004 and 2008. The mean follow-up was 7.1 years (range 5.3 to 9.3 years, minimum 5 years after surgery). Osteointegration of the implant and remodeling of bone tissue around the implant and its ribs were evaluated by digital radiography and computed tomography, and clinical results according to Harris. The experiment was based on the execution of pull-out tests after the implantation of TC cups in cadaveric bovine pelves. We evaluated the dependence of tensile forces in the axis of the implant on extraction of the metal cup from the bone bed. Four tests were conducted with the cup fixed...
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Bone remodeling in rheumatic diseases: Bone loss in juvenile idiopathic arthritis
Brábníková Marešová, Kristýna ; Štěpán, Jan (advisor) ; Blahoš, Jaroslav (referee) ; Hrnčíř, Zbyněk (referee)
Introduction: The inflammation plays the essential role in the bone loss in juvenile idiopathic arthritis (JIA). Proinflammatory cytokines and also glucocorticoids (GCs) may activate bone resorption by osteoclasts. Simultaneously, bone formation can be attenuated, especially by inhibitors of proteins, which control the osteoblast differentiation. The aim was to verify the hypothesis that in patients with highly active JIA, reduction of bone formation via Wingless (Wnt) proteins inhibitors - Dickkopf 1 (Dkk-1) and sclerostin could be found. Except the densitometry measurements of bone and lean mass, we assessed markers of disease activity, bone metabolism and remodeling in young adult patients with JIA before and during 2 years of anti TNFα (tumour necrosis factor α) treatment, which decreases disease activity. Results: In patients with JIA before antiTNFα treatment, bone mineral density (BMD, g/cmš) was significantly reduced compared to controls. Values of BMD and body composition in JIA significantly depended on disease duration and GCs treatment. Serum concentration of sclerostin was significantly elevated in JIA compared to values in healthy controls. Values of the other monitored markers did not differ between JIA and controls. In patients with JIA, Dkk-1 correlated positively with C-reactive...
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Circadian rhythm of parathyroid hormone and bone remodeling: implication for the osteoporosis treatment with teriparatide (parathormone [1-34])
Rašková, Mária ; Zikán, Vít (advisor) ; Žofková, Ivana (referee) ; Perlík, František (referee)
Circadian rhythm of parathyroid hormone (PTH) is well documented, but its physiological role is not fully understood. In healthy individuals, biochemical markers of bone remodeling follow a similar circadian rhythm to PTH with a nocturnal rise in bone resorption and formation. The loss of PTH diurnal variation was observed not only in primary hyperparathyroidism, but also in patients with postmenopausal osteoporosis. Continuously elevated concentrations of PTH lead to excessive stimulation of bone resorption, whereas intermittent PTH administration has a strong osteoanabolic effect in patients with osteoporosis. It has not been examined whether the skeletal sensitivity to PTH action depends also on the time of its application. The aim of our study was to verify the hypothesis that the application of teriparatide (TPTD, recombinant human PTH [1-34]) at different times of the day in the context of its diurnal variability affects the physiological circadian rhythm of bone remodeling and also the bone mineral density (BMD) after the long-term TPTD treatment. Fourteen women with postmenopausal osteoporosis treated with 20 micrograms of TPTD daily, applied subcutaneously either in the morning or evening, were included in the first study. The concentration of serum C-terminal telopeptide of type I collagen...
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Remodelace kostí po náhradě kyčelního kloubu. Numerické modelování a srovnání s klinickými pozorováními
Klika, Václav ; Maršík, František ; Landor, I.
The stress-strain changes in the surroundings of the hip-joint implant have dramatic impact on the response from the living bone tissue – by the remodeling process. This process is divided into three stages that can be described by five ordinary differential equations for the concentrations of five relevant chemical components. The driving force for the remodeling process is the dynamic loading. It is apparent that the joint implant creates a very new condition for natural remodeling process. In presented paper we simulate the consequences caused by remodeling phenomenon and compare it to clinical studies.
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