The clinical gold standard is bone auto-grafting, but autologous grafting can lead to donor site ... more The clinical gold standard is bone auto-grafting, but autologous grafting can lead to donor site morbidity and limited donor site availability; allogeneic grafting can lead to infection. Polymer scaffolds or composites will be the best bone substitutes. Our early researches show that biodegradable hydrogels or microsphere comprehended hydroxyapatite(HAp), tricalcium phosphate(TCP) or other osteoconductive molecules will enhance bone defects repairing. The objective of our study was to investigate the in vivo performance of bone defects implanted with novel composite (thermosensitive hydrogel mPEG-PLGA /HAp/TCP).
Poly(methyl methacrylate) (PMMA) has been widely used in orthopedic applications, but bone ingrow... more Poly(methyl methacrylate) (PMMA) has been widely used in orthopedic applications, but bone ingrowth and toxic monomer release are drawback of this material. Particle reinforcement with osteoconductive substitute, such as calcium sulfate (CaSO4), is one of the solutions used to modify PMMA bone cement. The current study investigated the mechanical, chemical and biological properties of CaSO4-augmented bone cement. Mechanical strength was measured by a material testing machine. The concentration of methyl methacrylate (MMA) monomer from the various formulations of PMMA mixed with CaSO4 was measured by ultra-performance liquid chromatography (UPLC). CCK-8 assay and ALP assay were performed to evaluate cytotoxicity of released MMA monomer and cell differentiation. The attachment of cells to CaSO4-augmented bone cement discs was observed by confocal and scanning electron microscopy, and surface topography was also evaluated by atomic force microscopy. The results revealed that increased CaSO4 weight ratios led to compromised mechanical strength and increased MMA monomer release. Cell density and cell differentiation on CaSO4-augmented bone cement discs were decreased at CaSO4 weight ratios above 10%. In addition, the presence of micropores on the surface and surface roughness were both increased for PMMA composite discs containing higher levels of CaSO4. These results demonstrated that fewer MC3T3-E1 cells on the surface of CaSO4–PMMA composites was correlated to increased MMA monomer release, micropore number and surface roughness. In summary, the augmentation of a higher proportion of CaSO4 (>10 wt. %) to PMMA did not promote the biological properties of traditional PMMA bone cement.
Results Pg 2 Last sentence, should read: “that of cannulated screws...” Reply: Thank you for noti... more Results Pg 2 Last sentence, should read: “that of cannulated screws...” Reply: Thank you for noting this problem. This error was corrected accordingly. (Page 3, the last Paragraph) Background section Pg 4, 2 nd Paragraph: “osteoporotic bone decreases”; “screw holding power have”; Reply: These two errors were corrected accordingly. (Page 4, 2 nd Paragraph) Pg 4 3 rd Paragraph: “Our review of the literature found that most...” Reply: This error was corrected accordingly. (Page 4, 3 rd Paragraph) Methods section Pg 8 Last sentence “...pilot hole accompanied with progressive needle retraction out of the test block...” Reply: This error was corrected accordingly. (Page 9, Line 8) Pg 9 Second sentence “the screws were randomly...” Reply: This error was corrected accordingly. (Page 9, Line 12)
Pedicle screws with PMMA cement augmentation have been shown to significantly improve the fixatio... more Pedicle screws with PMMA cement augmentation have been shown to significantly improve the fixation strength in a severely osteoporotic spine. However, the efficacy of screw fixation for different cement augmentation techniques, namely solid screws with retrograde cement pre-filling versus cannulated screws with cement injection through perforation, remains unknown. Conical and cylindrical pedicle screws with solid or cannulated designs were installed using the aforementioned cement augmentation techniques. Uniform synthetic bones simulating severe osteoporosis was used to provide a platform for each screw design and cement augmentation technique. Pedicle screws were then tested for axial pullout failure using a mechanical testing machine. The results revealed the following 1) Regardless of the screw outer geometry (conical or cylindrical), solid screws with retrograde cement pre-filling exhibited significantly higher pullout strength as compared to that of cannulated screw with ceme...
Formosan Journal of Musculoskeletal Disorders, 2015
Background: Bone morphogenetic protein 2 (BMP-2) has been frequently used for bone regeneration. ... more Background: Bone morphogenetic protein 2 (BMP-2) has been frequently used for bone regeneration. The purpose of this study was to design a gene vector to deliver the BMP-2 plasmid into cells. Polyethylene imine (PEI) is commonly used for gene transfer, however the high cytotoxicity often leads to decreased transfection efficiency. Solutions to this problem have been widely discussed, one of which being the grafting of a highly biocompatibility polymer such as chondroitin sulfate (CS). Methods: Different molecular weights (1,800 and 25,000 g/mol) of PEI were grafted onto CS (PEI1.8K-g-CS and PEI25K-g-CS, respectively) through the ethyldimethylaminopropyl carbodiimide/ N-hydroxysuccinimide reaction. This modification resulted in a non-viral gene carrier with improved biocompatibility as well as enhanced transfection efficiency compared to PEI alone. Cytotoxicity toward human embryonic kidney cell line (293T) was assayed. Results: Cell viability in the PEI-grafted-CS group was higher t...
Journal of Materials Science: Materials in Medicine, 2021
The formation of a nano-apatite surface layer is frequently considered a measure of bioactivity, ... more The formation of a nano-apatite surface layer is frequently considered a measure of bioactivity, especially for non-phosphate bioceramics. In the present study, strontium-doped calcium sulfate, (Ca,Sr)SO4, was used to verify the feasibility of this measure. The (Ca,Sr)SO4 specimen was prepared by mixing 10% SrSO4 by weight with 90% CaSO4·½H2O powder by weight. A solid solution of (Ca,7.6%Sr)SO4 was then produced by heating the powder mixture at 1100 °C for 1 h. The resulting (Ca,Sr)SO4 specimen was readily degradable in phosphate solution. A newly formed surface layer in the form of flakes was formed within one day of specimen immersion in phosphate solution. Structural and microstructure–compositional analyses indicated that the flakes were composed of octacalcium phosphate (OCP) crystals. An amorphous interface containing OCP nanocrystals was found between the newly formed surface layer and the remaining (Ca,Sr)SO4 specimen. The specimen was also implanted into a rat distal femur ...
Introduction: In patients under immunosuppression or severe sepsis, it is sometimes manifested as... more Introduction: In patients under immunosuppression or severe sepsis, it is sometimes manifested as coexisting septic arthritis and spondylitis. The aim of this study is to evaluate and investigate the risk factors of infectious spondylitis associated with septic arthritis. Methods: The study retrospectively reviewed the patients diagnosed with infectious spondylitis between January 2010 and September 2018 for risk factors of coexisting major joint septic arthritis. Results: A total of 10 patients with infectious spondylitis and coexisting septic arthritis comprised the study group. Fifty matched patients with solely infectious spondylitis were selected as the control group. Major risk factors include preoperative C-reactive protein (p = 0.001), hypoalbuminemia (p = 0.011), history of total joint replacement (p < 0.001), duration of preoperative antibiotics treatment (p = 0.038) and psoas muscle abscess (p < 0.001). Conclusion: Infectious spondylitis and septic arthritis are tho...
Study Design: Biomechanical study. Objective: Cross-links are a type of common clinical spinal in... more Study Design: Biomechanical study. Objective: Cross-links are a type of common clinical spinal instrumentation. However, the effects of the position and number of cross-links have never been investigated in long-segment spinal fixation, and the variables have not been optimized. We conducted an in vitro biomechanical study by using a porcine long-segment spinal model with 5 different crosslink configurations to determine the optimal construct for clinical practice. Methods: Five modalities with paired segmental screws from T15-L5 were tested in 20 porcine spines. The spines without cross-links composed the control group, Group A; those with a single cross-link from L2-3 composed Group B; those with 2 cross-links from L1-2 and L3-4 composed Group C; those with 2 cross-links from T15-L1 and L4-5 composed Group D; and those with 3 cross-links from T15-L1, L2-3 and L4-5 composed Group E. Spinal stiffnesses in flexion, extension, lateral bending, and axial rotation were compared among 5 ...
Osteitis deformans, also known as Paget's disease, is characterized by accelerated osteoclast... more Osteitis deformans, also known as Paget's disease, is characterized by accelerated osteoclastic activity followed by ineffective osteoblastic activity resulting in a deformed and fragile bone. It is more prevalent in Western Europe and relatively rare in Eastern Asia. It predominantly involves the lumbar spine, pelvis, and femur, frequently as polyostotic and rarely as monostotic disease. Here, we report a 64-year-old female, who presented with severe progressive back pain with no neurological symptoms. Radiographs revealed a picture frame L1 vertebra which was deformed and enlarged with loss of normal alignment. Magnetic resonance imaging revealed bone marrow changes involving all columns of L1 vertebra. Whole-body technetium-99 bone scan showed a solitary increased uptake of radioisotope by L1 vertebra. Considering the possibility of metastatic tumors, blood investigations were drawn for tumor markers which were within normal limits. A computed tomography-guided biopsy was done to facilitate diagnosis. Histopathology sections showed a mosaic pattern of bony trabeculae with multinucleated osteoclasts causing erosions and tunneling. A diagnosis of monostotic Paget's disease was made which satisfactorily responded to single-dose zoledronic acid treatment. A comprehensive literature review is provided.
Background The risk factors, incidence, and clinical management of pulmonary cement embolism and ... more Background The risk factors, incidence, and clinical management of pulmonary cement embolism and neurological deficit during percutaneous vertebroplasty (PVP) were evaluated. Methods Three thousand one hundred and seventy-five patients with symptomatic osteoporotic vertebral compression fractures (OVCFs) treated with PVP were retrospectively reviewed in a single institution. Clinical parameters such as age, gender, number of fractures, and time from fracture to vertebroplasty were recorded at the time of surgery. Image and surgical parameters including the amount of cement, the vertebral level, uni- or bipedicle surgical approach, and leakage pattern were recorded. Results Type-C leakage, including paraspinal (25%), intradiscal (26%), and posterior (0.7%) leakage, was more common than type-B (11.4%) and type-S leaks (4.9%). Cement leakage into the spinal canal (type-C posterior) occurred in 26 patients (0.7%), and four patients needed surgical decompression. Three in nine patients w...
Adolescent idiopathic scoliosis, in which obvious curves are visible in radiographic images, is a... more Adolescent idiopathic scoliosis, in which obvious curves are visible in radiographic images, is also seen in combination with lumps in the back. These lumps contribute to inclination, which can be measured by a scoliometer. To the authors' knowledge, there are no previous formulas combining thoracic and lumbar scoliometer values simultaneously to predict thoracic and lumbar Cobb angles, respectively. This study aimed to create more accurate two-parameter mathematical formulas for predicting thoracic and lumbar Cobb angles. Between Dec. 2012 and Jan. 2013, patients diagnosed with idiopathic scoliosis in an outpatient clinic were enrolled. The maximal trunk rotations at the thoracic and lumbar regions were recorded with a scoliometer. Right asymmetry hump was deemed positive (+), and left asymmetry hump was deemed negative (-). The Cobb angles were measured with a Picture Archiving and Communication System. Statistical analysis included Pearson's correlation coefficient, multi...
Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. Howev... more Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. However, the use of PMMA has some drawbacks, including the material’s excessive stiffness, exothermic polymerization, and short handling time. This study aimed to create an ideal modified bone cement to solve the above-mentioned problems. Modified bone cements were prepared by combining PMMA with three different volume fractions of castor oil (5%, 10%, and 15%). The peak polymerization temperatures, times to achieve the peak polymerization temperature, porosities, densities, modulus and maximum compression strengths of standard (without castor oil), and modified cements were investigated following storage at ambient temperature (22°C) or under precooling conditions (3°C). Six specimens were tested in each group of the aforementioned parameters. Increasing castor oil content and precooling treatment effectively decreased the peak polymerization temperatures and increased the duration to achiev...
Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. Howev... more Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. However, the use of PMMA has some drawbacks, including the material’s excessive stiffness, exothermic polymerization, and short handling time. This study aimed to create an ideal modified bone cement to solve the above-mentioned problems. Modified bone cements were prepared by combining PMMA with three different volume fractions of castor oil (5%, 10%, and 15%). The peak polymerization temperatures, times to achieve the peak polymerization temperature, porosities, densities, modulus and maximum compression strengths of standard (without castor oil), and modified cements were investigated following storage at ambient temperature (22°C) or under precooling conditions (3°C). Six specimens were tested in each group of the aforementioned parameters. Increasing castor oil content and precooling treatment effectively decreased the peak polymerization temperatures and increased the duration to achiev...
Osteoporosis is a bone disease that afflicts millions of people around the world, and a variety o... more Osteoporosis is a bone disease that afflicts millions of people around the world, and a variety of spinal integrity issues, such as degenerative spinal stenosis and spondylolisthesis, are frequently concomitant with osteoporosis and are sometimes treated with spinal interbody fusion surgery. Previous studies have demonstrated the efficacy of strontium ranelate (SrR) treatment of osteoporosis in improving bone strength, promoting bone remodeling, and reducing the risk of fractures, but its effects on interbody fusion surgery have not been adequately investigated. SrR-treated rats subjected to interbody fusion surgery exhibited significantly higher lumbar vertebral bone mineral density after 12 weeks of treatment than rats subjected to the same surgery but not treated with SrR. Furthermore, histological and radiographic assessments showed that a greater amount of newly formed bone tissue was present and that better fusion union occurred in the SrR-treated rats than in the untreated ra...
Elderly patients with chronic nonresolving symptoms due to degenerative spine pathologies are pro... more Elderly patients with chronic nonresolving symptoms due to degenerative spine pathologies are prone to have poor surgical outcomes and hardware-related complications, especially following multilevel instrumented lumbar fusion surgeries. With intention of analyzing if teriparatide can be an effective adjunct therapy to surgical management, radiological outcomes are studied. Sixty-two elderly patients were divided into 2 similar groups. Group 1 (n = 30; mean age = 69.83 years; fusion levels = 137; screws = 269) had taken teriparatide (20 mcg SC injection, once daily) for a duration of 7.4 ± 2.4 months following surgery and Group 2 (n = 32; mean age = 70.38 years; fusion levels = 144; screws = 283) did not take teriparatide. Radiological evaluation was done to determine the state of postero lateral fusion mass and to investigate the incidence of pedicle screw loosening at 1-year follow-up. Unilateral or bilateral bridging bone formation across the transverse process of adjacent vertebr...
Wnt signaling plays an important role in development and maintenance of many organs and tissues. ... more Wnt signaling plays an important role in development and maintenance of many organs and tissues. The most-studied secreted Wnt inhibitors are sclerostin (SOST), Dickkopf-related protein 1 (DKK-1), and secreted frizzled related protein 1 (SFRP-1) which play important roles in bone turnover. The present study investigated the relationship between serum Wnt inhibitors and diseases with excessive ossification structures, such as ossification of posterior longitudinal ligament (OPLL), ankylosing spondylitis (AS), diffuse idiopathic skeletal hyperostosis (DISH), and ossification of yellow ligament (OYL). Twenty-five patients with AS, DISH, OPLL, or OYL were recruited in this study. Fasting peripheral blood samples were collected from all patients and nine controls. Various biomarkers of bone turnover including osteocalcin (OSC), osteoprotegerin (OPG), SFRP-1, DKK-1, and SOST were investigated. Our data showed that serum levels of OSC were higher, but Dkk-1 levels were lower in AS, DISH, O...
Pyogenic spondylodiscitis is a form of spinal infection that can result in severe back pain and e... more Pyogenic spondylodiscitis is a form of spinal infection that can result in severe back pain and even death. However, information is lacking on the relative effectiveness of various therapies. A retrospective chart review was conducted to investigate whether early surgical treatment of pyogenic spondylodiscitis coupled with intravenous antibiotics results in better patient prognoses than intravenous antibiotics therapy alone. All patients treated for pyogenic spondylodiscitis at a single medical center from July 2006 to July 2011 were retrospectively reviewed. The inclusion criteria consisted of diagnosis of an early stage infection without neurological deficit, and patients without severe sepsis who were suitable candidates for early surgery as determined by a Pittsburgh bacteremia score < 4, and patients with delayed diagnosis and lost to outpatient follow-up were excluded. Clinical outcomes included patient demographic data, kyphosis angle, length of treatment, Oswestry Disabil...
The clinical gold standard is bone auto-grafting, but autologous grafting can lead to donor site ... more The clinical gold standard is bone auto-grafting, but autologous grafting can lead to donor site morbidity and limited donor site availability; allogeneic grafting can lead to infection. Polymer scaffolds or composites will be the best bone substitutes. Our early researches show that biodegradable hydrogels or microsphere comprehended hydroxyapatite(HAp), tricalcium phosphate(TCP) or other osteoconductive molecules will enhance bone defects repairing. The objective of our study was to investigate the in vivo performance of bone defects implanted with novel composite (thermosensitive hydrogel mPEG-PLGA /HAp/TCP).
Poly(methyl methacrylate) (PMMA) has been widely used in orthopedic applications, but bone ingrow... more Poly(methyl methacrylate) (PMMA) has been widely used in orthopedic applications, but bone ingrowth and toxic monomer release are drawback of this material. Particle reinforcement with osteoconductive substitute, such as calcium sulfate (CaSO4), is one of the solutions used to modify PMMA bone cement. The current study investigated the mechanical, chemical and biological properties of CaSO4-augmented bone cement. Mechanical strength was measured by a material testing machine. The concentration of methyl methacrylate (MMA) monomer from the various formulations of PMMA mixed with CaSO4 was measured by ultra-performance liquid chromatography (UPLC). CCK-8 assay and ALP assay were performed to evaluate cytotoxicity of released MMA monomer and cell differentiation. The attachment of cells to CaSO4-augmented bone cement discs was observed by confocal and scanning electron microscopy, and surface topography was also evaluated by atomic force microscopy. The results revealed that increased CaSO4 weight ratios led to compromised mechanical strength and increased MMA monomer release. Cell density and cell differentiation on CaSO4-augmented bone cement discs were decreased at CaSO4 weight ratios above 10%. In addition, the presence of micropores on the surface and surface roughness were both increased for PMMA composite discs containing higher levels of CaSO4. These results demonstrated that fewer MC3T3-E1 cells on the surface of CaSO4–PMMA composites was correlated to increased MMA monomer release, micropore number and surface roughness. In summary, the augmentation of a higher proportion of CaSO4 (>10 wt. %) to PMMA did not promote the biological properties of traditional PMMA bone cement.
Results Pg 2 Last sentence, should read: “that of cannulated screws...” Reply: Thank you for noti... more Results Pg 2 Last sentence, should read: “that of cannulated screws...” Reply: Thank you for noting this problem. This error was corrected accordingly. (Page 3, the last Paragraph) Background section Pg 4, 2 nd Paragraph: “osteoporotic bone decreases”; “screw holding power have”; Reply: These two errors were corrected accordingly. (Page 4, 2 nd Paragraph) Pg 4 3 rd Paragraph: “Our review of the literature found that most...” Reply: This error was corrected accordingly. (Page 4, 3 rd Paragraph) Methods section Pg 8 Last sentence “...pilot hole accompanied with progressive needle retraction out of the test block...” Reply: This error was corrected accordingly. (Page 9, Line 8) Pg 9 Second sentence “the screws were randomly...” Reply: This error was corrected accordingly. (Page 9, Line 12)
Pedicle screws with PMMA cement augmentation have been shown to significantly improve the fixatio... more Pedicle screws with PMMA cement augmentation have been shown to significantly improve the fixation strength in a severely osteoporotic spine. However, the efficacy of screw fixation for different cement augmentation techniques, namely solid screws with retrograde cement pre-filling versus cannulated screws with cement injection through perforation, remains unknown. Conical and cylindrical pedicle screws with solid or cannulated designs were installed using the aforementioned cement augmentation techniques. Uniform synthetic bones simulating severe osteoporosis was used to provide a platform for each screw design and cement augmentation technique. Pedicle screws were then tested for axial pullout failure using a mechanical testing machine. The results revealed the following 1) Regardless of the screw outer geometry (conical or cylindrical), solid screws with retrograde cement pre-filling exhibited significantly higher pullout strength as compared to that of cannulated screw with ceme...
Formosan Journal of Musculoskeletal Disorders, 2015
Background: Bone morphogenetic protein 2 (BMP-2) has been frequently used for bone regeneration. ... more Background: Bone morphogenetic protein 2 (BMP-2) has been frequently used for bone regeneration. The purpose of this study was to design a gene vector to deliver the BMP-2 plasmid into cells. Polyethylene imine (PEI) is commonly used for gene transfer, however the high cytotoxicity often leads to decreased transfection efficiency. Solutions to this problem have been widely discussed, one of which being the grafting of a highly biocompatibility polymer such as chondroitin sulfate (CS). Methods: Different molecular weights (1,800 and 25,000 g/mol) of PEI were grafted onto CS (PEI1.8K-g-CS and PEI25K-g-CS, respectively) through the ethyldimethylaminopropyl carbodiimide/ N-hydroxysuccinimide reaction. This modification resulted in a non-viral gene carrier with improved biocompatibility as well as enhanced transfection efficiency compared to PEI alone. Cytotoxicity toward human embryonic kidney cell line (293T) was assayed. Results: Cell viability in the PEI-grafted-CS group was higher t...
Journal of Materials Science: Materials in Medicine, 2021
The formation of a nano-apatite surface layer is frequently considered a measure of bioactivity, ... more The formation of a nano-apatite surface layer is frequently considered a measure of bioactivity, especially for non-phosphate bioceramics. In the present study, strontium-doped calcium sulfate, (Ca,Sr)SO4, was used to verify the feasibility of this measure. The (Ca,Sr)SO4 specimen was prepared by mixing 10% SrSO4 by weight with 90% CaSO4·½H2O powder by weight. A solid solution of (Ca,7.6%Sr)SO4 was then produced by heating the powder mixture at 1100 °C for 1 h. The resulting (Ca,Sr)SO4 specimen was readily degradable in phosphate solution. A newly formed surface layer in the form of flakes was formed within one day of specimen immersion in phosphate solution. Structural and microstructure–compositional analyses indicated that the flakes were composed of octacalcium phosphate (OCP) crystals. An amorphous interface containing OCP nanocrystals was found between the newly formed surface layer and the remaining (Ca,Sr)SO4 specimen. The specimen was also implanted into a rat distal femur ...
Introduction: In patients under immunosuppression or severe sepsis, it is sometimes manifested as... more Introduction: In patients under immunosuppression or severe sepsis, it is sometimes manifested as coexisting septic arthritis and spondylitis. The aim of this study is to evaluate and investigate the risk factors of infectious spondylitis associated with septic arthritis. Methods: The study retrospectively reviewed the patients diagnosed with infectious spondylitis between January 2010 and September 2018 for risk factors of coexisting major joint septic arthritis. Results: A total of 10 patients with infectious spondylitis and coexisting septic arthritis comprised the study group. Fifty matched patients with solely infectious spondylitis were selected as the control group. Major risk factors include preoperative C-reactive protein (p = 0.001), hypoalbuminemia (p = 0.011), history of total joint replacement (p < 0.001), duration of preoperative antibiotics treatment (p = 0.038) and psoas muscle abscess (p < 0.001). Conclusion: Infectious spondylitis and septic arthritis are tho...
Study Design: Biomechanical study. Objective: Cross-links are a type of common clinical spinal in... more Study Design: Biomechanical study. Objective: Cross-links are a type of common clinical spinal instrumentation. However, the effects of the position and number of cross-links have never been investigated in long-segment spinal fixation, and the variables have not been optimized. We conducted an in vitro biomechanical study by using a porcine long-segment spinal model with 5 different crosslink configurations to determine the optimal construct for clinical practice. Methods: Five modalities with paired segmental screws from T15-L5 were tested in 20 porcine spines. The spines without cross-links composed the control group, Group A; those with a single cross-link from L2-3 composed Group B; those with 2 cross-links from L1-2 and L3-4 composed Group C; those with 2 cross-links from T15-L1 and L4-5 composed Group D; and those with 3 cross-links from T15-L1, L2-3 and L4-5 composed Group E. Spinal stiffnesses in flexion, extension, lateral bending, and axial rotation were compared among 5 ...
Osteitis deformans, also known as Paget's disease, is characterized by accelerated osteoclast... more Osteitis deformans, also known as Paget's disease, is characterized by accelerated osteoclastic activity followed by ineffective osteoblastic activity resulting in a deformed and fragile bone. It is more prevalent in Western Europe and relatively rare in Eastern Asia. It predominantly involves the lumbar spine, pelvis, and femur, frequently as polyostotic and rarely as monostotic disease. Here, we report a 64-year-old female, who presented with severe progressive back pain with no neurological symptoms. Radiographs revealed a picture frame L1 vertebra which was deformed and enlarged with loss of normal alignment. Magnetic resonance imaging revealed bone marrow changes involving all columns of L1 vertebra. Whole-body technetium-99 bone scan showed a solitary increased uptake of radioisotope by L1 vertebra. Considering the possibility of metastatic tumors, blood investigations were drawn for tumor markers which were within normal limits. A computed tomography-guided biopsy was done to facilitate diagnosis. Histopathology sections showed a mosaic pattern of bony trabeculae with multinucleated osteoclasts causing erosions and tunneling. A diagnosis of monostotic Paget's disease was made which satisfactorily responded to single-dose zoledronic acid treatment. A comprehensive literature review is provided.
Background The risk factors, incidence, and clinical management of pulmonary cement embolism and ... more Background The risk factors, incidence, and clinical management of pulmonary cement embolism and neurological deficit during percutaneous vertebroplasty (PVP) were evaluated. Methods Three thousand one hundred and seventy-five patients with symptomatic osteoporotic vertebral compression fractures (OVCFs) treated with PVP were retrospectively reviewed in a single institution. Clinical parameters such as age, gender, number of fractures, and time from fracture to vertebroplasty were recorded at the time of surgery. Image and surgical parameters including the amount of cement, the vertebral level, uni- or bipedicle surgical approach, and leakage pattern were recorded. Results Type-C leakage, including paraspinal (25%), intradiscal (26%), and posterior (0.7%) leakage, was more common than type-B (11.4%) and type-S leaks (4.9%). Cement leakage into the spinal canal (type-C posterior) occurred in 26 patients (0.7%), and four patients needed surgical decompression. Three in nine patients w...
Adolescent idiopathic scoliosis, in which obvious curves are visible in radiographic images, is a... more Adolescent idiopathic scoliosis, in which obvious curves are visible in radiographic images, is also seen in combination with lumps in the back. These lumps contribute to inclination, which can be measured by a scoliometer. To the authors' knowledge, there are no previous formulas combining thoracic and lumbar scoliometer values simultaneously to predict thoracic and lumbar Cobb angles, respectively. This study aimed to create more accurate two-parameter mathematical formulas for predicting thoracic and lumbar Cobb angles. Between Dec. 2012 and Jan. 2013, patients diagnosed with idiopathic scoliosis in an outpatient clinic were enrolled. The maximal trunk rotations at the thoracic and lumbar regions were recorded with a scoliometer. Right asymmetry hump was deemed positive (+), and left asymmetry hump was deemed negative (-). The Cobb angles were measured with a Picture Archiving and Communication System. Statistical analysis included Pearson's correlation coefficient, multi...
Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. Howev... more Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. However, the use of PMMA has some drawbacks, including the material’s excessive stiffness, exothermic polymerization, and short handling time. This study aimed to create an ideal modified bone cement to solve the above-mentioned problems. Modified bone cements were prepared by combining PMMA with three different volume fractions of castor oil (5%, 10%, and 15%). The peak polymerization temperatures, times to achieve the peak polymerization temperature, porosities, densities, modulus and maximum compression strengths of standard (without castor oil), and modified cements were investigated following storage at ambient temperature (22°C) or under precooling conditions (3°C). Six specimens were tested in each group of the aforementioned parameters. Increasing castor oil content and precooling treatment effectively decreased the peak polymerization temperatures and increased the duration to achiev...
Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. Howev... more Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. However, the use of PMMA has some drawbacks, including the material’s excessive stiffness, exothermic polymerization, and short handling time. This study aimed to create an ideal modified bone cement to solve the above-mentioned problems. Modified bone cements were prepared by combining PMMA with three different volume fractions of castor oil (5%, 10%, and 15%). The peak polymerization temperatures, times to achieve the peak polymerization temperature, porosities, densities, modulus and maximum compression strengths of standard (without castor oil), and modified cements were investigated following storage at ambient temperature (22°C) or under precooling conditions (3°C). Six specimens were tested in each group of the aforementioned parameters. Increasing castor oil content and precooling treatment effectively decreased the peak polymerization temperatures and increased the duration to achiev...
Osteoporosis is a bone disease that afflicts millions of people around the world, and a variety o... more Osteoporosis is a bone disease that afflicts millions of people around the world, and a variety of spinal integrity issues, such as degenerative spinal stenosis and spondylolisthesis, are frequently concomitant with osteoporosis and are sometimes treated with spinal interbody fusion surgery. Previous studies have demonstrated the efficacy of strontium ranelate (SrR) treatment of osteoporosis in improving bone strength, promoting bone remodeling, and reducing the risk of fractures, but its effects on interbody fusion surgery have not been adequately investigated. SrR-treated rats subjected to interbody fusion surgery exhibited significantly higher lumbar vertebral bone mineral density after 12 weeks of treatment than rats subjected to the same surgery but not treated with SrR. Furthermore, histological and radiographic assessments showed that a greater amount of newly formed bone tissue was present and that better fusion union occurred in the SrR-treated rats than in the untreated ra...
Elderly patients with chronic nonresolving symptoms due to degenerative spine pathologies are pro... more Elderly patients with chronic nonresolving symptoms due to degenerative spine pathologies are prone to have poor surgical outcomes and hardware-related complications, especially following multilevel instrumented lumbar fusion surgeries. With intention of analyzing if teriparatide can be an effective adjunct therapy to surgical management, radiological outcomes are studied. Sixty-two elderly patients were divided into 2 similar groups. Group 1 (n = 30; mean age = 69.83 years; fusion levels = 137; screws = 269) had taken teriparatide (20 mcg SC injection, once daily) for a duration of 7.4 ± 2.4 months following surgery and Group 2 (n = 32; mean age = 70.38 years; fusion levels = 144; screws = 283) did not take teriparatide. Radiological evaluation was done to determine the state of postero lateral fusion mass and to investigate the incidence of pedicle screw loosening at 1-year follow-up. Unilateral or bilateral bridging bone formation across the transverse process of adjacent vertebr...
Wnt signaling plays an important role in development and maintenance of many organs and tissues. ... more Wnt signaling plays an important role in development and maintenance of many organs and tissues. The most-studied secreted Wnt inhibitors are sclerostin (SOST), Dickkopf-related protein 1 (DKK-1), and secreted frizzled related protein 1 (SFRP-1) which play important roles in bone turnover. The present study investigated the relationship between serum Wnt inhibitors and diseases with excessive ossification structures, such as ossification of posterior longitudinal ligament (OPLL), ankylosing spondylitis (AS), diffuse idiopathic skeletal hyperostosis (DISH), and ossification of yellow ligament (OYL). Twenty-five patients with AS, DISH, OPLL, or OYL were recruited in this study. Fasting peripheral blood samples were collected from all patients and nine controls. Various biomarkers of bone turnover including osteocalcin (OSC), osteoprotegerin (OPG), SFRP-1, DKK-1, and SOST were investigated. Our data showed that serum levels of OSC were higher, but Dkk-1 levels were lower in AS, DISH, O...
Pyogenic spondylodiscitis is a form of spinal infection that can result in severe back pain and e... more Pyogenic spondylodiscitis is a form of spinal infection that can result in severe back pain and even death. However, information is lacking on the relative effectiveness of various therapies. A retrospective chart review was conducted to investigate whether early surgical treatment of pyogenic spondylodiscitis coupled with intravenous antibiotics results in better patient prognoses than intravenous antibiotics therapy alone. All patients treated for pyogenic spondylodiscitis at a single medical center from July 2006 to July 2011 were retrospectively reviewed. The inclusion criteria consisted of diagnosis of an early stage infection without neurological deficit, and patients without severe sepsis who were suitable candidates for early surgery as determined by a Pittsburgh bacteremia score < 4, and patients with delayed diagnosis and lost to outpatient follow-up were excluded. Clinical outcomes included patient demographic data, kyphosis angle, length of treatment, Oswestry Disabil...
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