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Osteoporosis is a skeletal disorder marked by compromised bone integrity, predisposing individuals, particularly older adults and postmenopausal women, to fractures. The advent of bioceramics for bone regeneration has opened up auspicious pathways for addressing osteoporosis. Research indicates that bioceramics can help bones grow back by activating bone morphogenetic protein (BMP), mitogen-activated protein kinase (MAPK), and wingless/integrated (Wnt)/ß-catenin pathways in the body when combined with stem cells, drugs, and other supports. Still, bioceramics have some problems, such as not being flexible enough and prone to breaking, as well as difficulties in growing stem cells and discovering suitable supports for different bone types. While there have been improvements in making bioceramics better for healing bones, it is important to keep looking for new ideas from different areas of medicine to make them even better. By conducting a thorough scrutiny of the pivotal role bioceramics play in facilitating bone regeneration, this review aspires to propel forward the rapidly burgeoning domain of scientific exploration. In the end, this appreciation will contribute to the development of novel bioceramics that enhance bone regrowth and offer patients with bone disorders alternative treatments.
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In the field of bone tissue engineering, which is being developed for the ideal restoration of bone defects, researchers are exploring the improvement of the bone regeneration efficacy of scaffolds through various approaches involving osteoconductive, osteoinductive, and angiogenic factors. In the current trend of research, there is also a suggestion that the topological factors of recent scaffolds may influence the attachment, migration, proliferation, and differentiation of bone cells. Building upon experimental confirmation of the effect of scaffold conformity with the defect site on enhanced bone regeneration in previous studies, we conducted this research to experimentally investigate the relationship between contact area with the defect site and bone regeneration efficacy. The results demonstrated that as the contact area of the scaffold increased, not only did the resistance to bone tissue growth increase, more significant bone regeneration also occurred, as evidenced through histological analysis and micro-CT analysis. This research confirms that the contact area between the scaffold and the defect site is a critical variable affecting bone regeneration efficacy, emphasizing its importance when designing customized scaffolds. This finding holds promising implications for future studies and applications in the field.
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The purpose of this study was to investigate the initiation of autophagy activation and apoptosis in nucleus pulposus cells under temporary compression (TC) and sustained compression (SC) to identify ideal research approaches in intervertebral disc degeneration. Various techniques were used: radiography (X-ray), magnetic resonance imaging (MRI), transmission electron microscope (TEM), H&E staining, Masson's trichrome staining, immunohistochemistry (IHC) (LC3, beclin-1, and cleaved caspase-3), and real-time polymerase chain reaction (RT-qPCR) for autophagy-related (beclin-1, LC3, and P62) and apoptosis-related (caspase-3 and PARP) gene expression analysis. X-ray and MRI revealed varying degrees of disc degeneration, ranging from moderate to severe in both groups. The severity was directly linked to compression duration, with SC resulting in notably severe central NP cell degeneration. Surprisingly, TC also caused similar, though less severe, degeneration. Elevated expression of LC3 and beclin-1 was identified after 6 weeks, but it notably declined after 12 weeks. Central NP cells in both groups exhibited increased expression of cleaved caspase-3 that was positively correlated with the duration of SC. TC showed fewer apoptotic markers compared to SC. LC3, beclin-1, and P62 mRNA expression peaked after 6 weeks and declined after 12 weeks in both groups. Cleaved caspase-3 and PARP expression peaked in SC, positively correlating with longer compression duration, while TC showed lower levels of apoptosis gene expression. Furthermore, TEM results revealed different events of the autophagic degradation process after 2 weeks of compression. TCmay be ideal for studying early triggered autophagy-mediated degeneration, while SC may be ideal for studying late or slower-triggered apoptosis-mediated degeneration.
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Degeneración del Disco Intervertebral , Humanos , Degeneración del Disco Intervertebral/metabolismo , Caspasa 3/genética , Beclina-1/genética , Beclina-1/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Apoptosis , AutofagiaRESUMEN
PURPOSE: The purpose of this study was to investigate autophagy in an extruded disc and to compare this activity with the activity in the remaining disc after lumbar disc herniation in the same patient. METHODS: In total, 12 patients (females 4, males 8) with the extruded type of lumbar disc herniation (LDH) were surgically treated. Their mean age was 54.3 ± 15.8 years (range: 29 ~ 78 years). The mean interval from the occurrence of symptoms to the operation was 9.8 ± 9.4 weeks (range: 2 ~ 24 weeks). The extruded discs were excised, and the remaining disc material removed, to prevent recurrence of herniation. Immediately after specimen collection, all tissues were stored at -70 °C prior to analysis. Autophagy was assessed immunohistochemically and via Western blotting for Atg5, Atg7, Atg12, Atg12L1, and Beclin-1. And the relationship between autophagy and apoptosis was investigated by correlation analysis of caspase-3 with autophagy proteins. RESULTS: The expression levels of autophagic markers were significantly increased in the extruded discs compared to the remaining discs within the same patients. The mean expression levels of Atg5, Atg7, Atg12, and Beclin-1 in extruded discs were statistically significantly higher than those in the remaining discs (P < 0.01, P < 0.001, P < 0.01, and P < 0.001 respectively). CONCLUSIONS: The autophagic pathway was more active in extruded disc material than in remaining disc material within the same patient. This may explain spontaneous resorption of the extruded disc after LDH.
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Desplazamiento del Disco Intervertebral , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Desplazamiento del Disco Intervertebral/cirugía , Beclina-1 , Vértebras Lumbares/cirugía , Discectomía , AutofagiaRESUMEN
Apoptosis has historically been considered the primary form of programmed cell death (PCD) and is responsible for regulating cellular processes during development, homeostasis, and disease. Conversely, necrosis was considered uncontrolled and unregulated. However, recent evidence has unveiled the significance of necroptosis, a regulated form of necrosis, as an important mechanism of PCD alongside apoptosis. The activation of necroptosis leads to cellular membrane disruption, inflammation, and vascularization. This process is crucial in various pathological conditions, including intervertebral disc degeneration (IVDD), neurodegeneration, inflammatory diseases, multiple cancers, and kidney injury. In recent years, extensive research efforts have shed light on the molecular regulation of the necroptotic pathway. Various stimuli trigger necroptosis, and its regulation involves the activation of specific proteins such as receptor-interacting protein kinase 1 (RIPK1), RIPK3, and the mixed lineage kinase domain-like (MLKL) pseudokinase. Understanding the intricate mechanisms governing necroptosis holds great promise for developing novel therapeutic interventions targeting necroptosis-associated IVDD. The objective of this review is to contribute to the growing body of scientific knowledge in this area by providing a comprehensive overview of necroptosis and its association with IVDD. Ultimately, these understandings will allow the development of innovative drugs that can modulate the necroptotic pathway, offering new therapeutic avenues for individuals suffering from necroptosis.
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Degeneración del Disco Intervertebral , Proteínas Quinasas , Humanos , Proteínas Quinasas/metabolismo , Necroptosis/fisiología , Apoptosis , Necrosis/patología , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismoRESUMEN
Osteoporosis and osteoporotic fractures cause socioeconomic concerns, and medical system and policies appear insufficient to prepare for these issues in Korea, where the older adult population is rapidly increasing. Many countries around the world are already responding to osteoporosis and osteoporotic fractures by adopting fracture liaison service (FLS), and such an attempt has only begun in Korea. In this article, we introduce the operation methods for institutions implementing FLS and characteristics of services, and activities of the FLS Committee for FLS implementation in the Korean Society for Bone and Mineral Research. In addition, we hope that the current position statement will contribute to the implementation of FLS in Korea and impel policy changes to enable a multidisciplinary and integrated FLS operated under the medical system.
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Lumbar interbody fusion (LIF) is an excellent treatment option for a number of lumbar diseases. LIF can be performed through posterior, transforaminal, anterior, and lateral or oblique approaches. Each technique has its own pearls and pitfalls. Through LIF, segmental stabilization, neural decompression, and deformity correction can be achieved. Minimally invasive surgery has recently gained popularity and each LIF procedure can be performed using minimally invasive techniques to reduce surgery-related complications and improve early postoperative recovery. Despite advances in surgical technology, surgery-related complications after LIF, such as pseudoarthrosis, have not yet been overcome. Although autogenous iliac crest bone graft is the gold standard for spinal fusion, other bone substitutes are available to enhance fusion rate and reduce complications associated with bone harvest. This article reviews the surgical procedures and characteristics of each LIF and the osteobiologics utilized in LIF based on the available evidence.
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Background and Objectives: The majority of research on the effects of osteoporosis drugs has measured the bone mineral density (BMD) of the spine and femur through dual-energy X-ray absorptiometry (DEXA) and compared and analyzed the effects of the drugs through changes in the BMD values. This study aims to compare osteoclast and sclerostin expression in osteocytes after risedronate therapy by obtaining femoral heads from patients with hip fractures. Materials and Methods: We obtained the femoral heads of 10 female patients (age: ≥65 years) who received risedronate therapy for at least 1 year through hip arthroplasty during 2019−2021 (risedronate group). Meanwhile, 10 patients who had never received osteoporosis treatment were selected as controls using propensity scores with age, body mass index, and bone density as covariates (control group). While the osteoclast count was evaluated using tartrate-resistant acid phosphatase (TRAP) staining, the sclerostin expression in osteocytes was assessed using immunohistochemistry. Moreover, Western blotting and polymerase chain reaction (PCR) were performed for receptor activation of nuclear factor kappa-Β ligand (RANKL), RANK, osteoprotegerin (OPG), sclerostin, and bone morphogenetic protein-2 (BMP2). Results: TRAP staining revealed significantly more TRAP-positive cells in the control group (131.75 ± 27.16/mm2) than in the risedronate group (28.00 ± 8.12/mm2). Moreover, sclerostin-positive osteocytes were expressed more in the control group (364.12 ± 28.12/mm2) than in the risedronate group (106.93 ± 12.85/mm2). Western blotting revealed that the expressions of RANKL, RANK, sclerostin, and BMP2 were higher in the control group than in the risedronate group (p < 0.05). Furthermore, RANK, sclerostin, and OPG protein levels were higher in the control group than in the risedronate group. Conclusions: In this study, the risedronate group demonstrated lower osteoclast activity and sclerostin expression in osteocytes in the femoral head than the control group.
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Fracturas de Cadera , Osteoporosis , Humanos , Femenino , Anciano , Osteocitos/metabolismo , Osteoclastos , Ácido Risedrónico/farmacología , Ácido Risedrónico/uso terapéutico , Cabeza Femoral , Ligando RANK/metabolismo , Estudios Retrospectivos , Osteoporosis/metabolismo , Densidad Ósea , Fracturas de Cadera/tratamiento farmacológicoRESUMEN
The meniscus has poor intrinsic regenerative capability, and its injury inevitably leads to articular cartilage degeneration. Although there are commercialized off-the-shelf alternatives to achieve total meniscus regeneration, each has its own shortcomings such as individualized size matching issues and inappropriate mechanical properties. We manufactured a polycaprolactone-based patient-specific designed framework via a Computed Tomography scan images and 3D-printing technique. Then, we completed the hybrid-scaffold by combining the 3D-printed framework and mixture micro-size composite which consists of polycaprolactone and sodium chloride to create a cell-friendly microenvironment. Based on this hybrid-scaffold with an autograft cell source (fibrochondrocyte), we assessed mechanical and histological results using the rabbit total meniscectomy model. At postoperative 12-week, hybrid-scaffold achieved neo-meniscus tissue formation, and its shape was maintained without rupture or break away from the knee joint. Histological and immunohistochemical analysis results showed obvious ingrowth of the fibroblast-like cells and chondrocyte cells as well as mature lacunae that were embedded in the extracellular matrix. Hybrid-scaffolding resulted in superior shape matching as compared to original meniscus tissue. Histological analysis showed evidence of extensive neo-meniscus cell ingrowth. Additionally, the hybrid-scaffold did not induce osteoarthritis on the femoral condyle surface. The 3D-printed hybrid-scaffold may provide a promising approach that can be applied to those who received total meniscal resection, using patient-specific design and autogenous cell source.
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BACKGROUND: Epidural fibrosis is one of the aetiologies of pain following a spinal revision surgery. It is reported that the specific members of the mitogen - activated protein kinases (MAPK) family might mediate neuropathic pain. However, roles of epidural fibrosis caused by repeated spinal surgeries and pain-related proteins in causing the post spinal surgery syndrome remain unknown. Using a rat spinal surgery epidural fibrosis and adhesion model, in this study, we evaluated and investigated the relationship between pain markers and epidural fibrosis. METHODS: Sprague-Dawley rats that underwent the spinal surgery were divided into three groups: group A (single laminectomy), group B (two repeated surgeries) and group C (three repeated surgeries). Dural thickness was measured in each experimental group, and immunohistochemical analysis and western blotting of mitogen-activated protein kinases were performed (ERK, p38 and JNK) using the spine cord. RESULTS: Dural thickness was 6.363 ± 1.911 µm in group A, 13.238 ± 2.123 µm in group B and 19.4 ± 2.115 µm in group C, respectively. In the western blotting, phosphorylated ERK expression gradually increased with the number of repeated surgeries, and expression in groups B (1.77-fold) and C (2.42-fold) increased as compared to expression in group A. Phosphorylated p38 showed an increasing trend with the number of repeated surgeries, and groups B (1.17-fold) and C (1.33-fold) expression increased compared with group A. However, phosphorylated JNK expression did not gradually increase with the number of repeated surgeries, and groups B (1.62-fold) and C (1.43-fold) expression increased compared with group A. Excluding phosphorylated JNK, immunohistochemical analysis revealed that phosphorylated ERK and p38 expression gradually increased with the number of repeated surgeries in the spine dorsal horn, as evidenced by western blotting. CONCLUSIONS: Repeated spinal surgeries may increase dural thickness and expression of phosphorylated ERK and p38 in the spinal dorsal horn, and it suggests that the neuropathic pain is likely induced by epidural fibrosis and that the pain increases with the number of repeated surgeries.
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Neuralgia , Proteínas Quinasas p38 Activadas por Mitógenos , Animales , Fibrosis , Ratas , Ratas Sprague-Dawley , ReoperaciónRESUMEN
Among 3D-printed composite scaffolds for bone tissue engineering, researchers have been attracted to the use of zinc ions to improve the scaffold's anti-bacterial activity and prevent surgical site infection. In this study, we assumed that the concentration of zinc ions released from the scaffold will be correlated with the thickness of the zinc oxide coating on 3D-printed scaffolds. We investigated the adequate thickness of zinc oxide coating by comparing different scaffolds' characteristics, antibacterial activity, and in vitro cell response. The scaffolds' compressive modulus decreased as the zinc oxide coating thickness increased (10, 100 and 200 nm). However, the compressive modulus of scaffolds in this study were superior to those of other reported scaffolds because our scaffolds had a kagome structure and were made of composite material. In regard to the antibacterial activity and in vitro cell response, the in vitro cell proliferation on scaffolds with a zinc oxide coating was higher than that of the control scaffold. Moreover, the antibacterial activity of scaffolds with 100 or 200 nm-thick zinc oxide coating on Escherichia coli was superior to that of other scaffolds. Therefore, we concluded that the scaffold with a 100 nm-thick zinc oxide coating was the most appropriate scaffold to use as a bone-regenerating scaffold, given its mechanical property, its antibacterial activity, and its in vitro cell proliferation.
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OBJECTIVES: To elaborate on the relationship between degeneration grade and autophagy expression in human nucleus pulposus obtained from surgical procedures. METHODS: For the 16 patients included in the present study, we determined the Pfirrmann classifications of degenerative lesions by MRI. Western blot analysis, LC3, LAMP2, and p62 protein expressions were quantified in different degeneration grades of disc nucleus pulposus. Double immunofluorescence staining was used to show co-localization of LC3 and LAMP2, and immunohistochemistry to show LC3 and p62 in the nucleus pulposus. RESULTS: In the western blot analysis, LC3-II was highly expressed in grade III and decreased progressively from grade IV to V. In addition, LC3-II expression in grade III was significantly higher than in grade II, IV, and V (P < 0.05). LAMP2 expression in grade V was significantly higher than that in grade II, III, and IV (P < 0.05). P62 increased with decreasing autophagy expression up through grade V. In the double staining, the LC3 level was highly expressed in grade III and decreased progressively from grades IV to V, as in the western blot analysis. LAMP2 rose with increasing disc degeneration grade through grade V. In the quantitative analysis of colocalization, grade III is significantly higher than grade II and V (P < 0.05). Immunohistochemical staining showed that LC3 was highly expressed in grade III but weakly expressed in other grades, with few positive areas around the nucleus pulposus. However, p62 increased progressively with increasing disc degeneration grade. CONCLUSION: Pfirrmann grade III disc degeneration showed that autophagosomes were formed, which led to the reversible decomposition of degenerative substances. Thus, by analyzing the effect of autophagy on degenerative discs, we showed the possibility of reversing degenerative changes, but only in grades III and lower.
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Autofagia , Degeneración del Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/patología , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patología , Anciano , Western Blotting , Femenino , Humanos , Proteína 2 de la Membrana Asociada a los Lisosomas/metabolismo , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Persona de Mediana Edad , Proteínas de Unión al ARN/metabolismoRESUMEN
STUDY DESIGN: Retrospective multicenter case series. OBJECTIVE: We sought to evaluate the safety and efficacy of anterior cervical plating in anterior cervical debridement and fusion (ACDF) for patients with cervical pyogenic spondylodiscitis (CPS). SUMMARY OF BACKGROUND DATA: Due to concerns about bacterial seeding on the foreign material after instrumentations in pyogenic infections, the safety and efficacy of anterior cervical plating for CPS are still undetermined and controversial. Little information is available about the safety and efficacy of anterior cervical plating to manage CPS. METHODS: Twenty-three patients who underwent ACDF with (nâ=â12) or without (nâ=â11) plating for CPS were included. The mean age was 62.6 years. Medical records were reviewed and radiological parameters including segmental height, segmental angle, C2-C7 angle, and fusion status were analyzed. The mean follow-up period after surgery was 21.3 months. RESULTS: After ACDF with plating, segmental height, segmental angle, and C2-C7 angle were significantly improved compared with preoperative conditions and remained well-maintained at the last follow-up. After ACDF without plating, three radiological parameters were also initially improved compared with preoperative condition, but significantly deteriorated to preoperative levels at the time of the last follow-up. The fusion rate was higher in the ACDF with plating group compared with the ACDF without plating group (90.9% vs. 63.6%; Pâ<â0.01). One patient who received ACDF with plating and four patients who received ACDF without plating underwent revision surgery due to nonunion or bone graft dislodgement. No recurrence of pyogenic spondylodiscitis occurred in either group. CONCLUSION: ACDF with plating showed better surgical outcomes compared with ACDF without plating for CPS. We recommend the use of anterior cervical plating, which can provide biomechanical stability, for better healing of CPS. To our knowledge, this is the largest surgical case series of CPS. LEVEL OF EVIDENCE: 4.
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Placas Óseas , Vértebras Cervicales/cirugía , Desbridamiento/métodos , Discitis/cirugía , Fusión Vertebral/métodos , Adulto , Anciano , Vértebras Cervicales/diagnóstico por imagen , Desbridamiento/instrumentación , Discitis/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reoperación/instrumentación , Reoperación/métodos , Estudios Retrospectivos , Fusión Vertebral/instrumentaciónRESUMEN
STUDY DESIGN: Retrospective case analyses. PURPOSE: To investigate the causes, diagnosis, and management of esophageal perforation, depending on the time of diagnosis. OVERVIEW OF LITERATURE: To date, few studies have addressed these issues. METHODS: A total of seven patients were included in this study. The patients were classified into three groups based on esophageal perforation diagnosis time: intraoperative (diagnosed during surgery), perioperative (diagnosed within 30 days postoperatively), and delayed (diagnosed >30 days postoperatively) groups. RESULTS: In the intraoperative group (N=2), infectious spondylitis was the main cause of esophageal perforation. Anterior plate and screw removal, followed by posterior instrumentation, was performed. The injured esophagus was managed by omentum flap repair in one patient and primary repair in one patient. In the perioperative group (N=2), revision surgery for infection and metal failure were the main causes of esophageal perforation. In both cases, food residue was drained on the third postoperative day. The injured esophagus was managed conservatively. In the delayed group (N=3), chronic irritation caused by metal failure was the main cause of esophageal perforation. In all patients, there was no associated infection. The anterior instrumentation was removed, and the two patients were treated by primary repair, and one patient was treated using sternocleidomastoid muscle flap. One patient in intraoperative group died of sepsis. CONCLUSIONS: The main cause of intraoperative esophageal perforation was esophageal adhesions because of infectious spondylitis. However, perioperative and delayed esophageal perforations were caused by chronic irritation because of metal failure. Anterior plate and screw removal was necessary, and posterior instrumentation and fusion may be considered, depending on the fusion status.
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Corticosteroids are commonly used for pain control in rotator cuff tear. Deregulated NF-κB activation is a hallmark of chronic inflammatory diseases and has been responsible for the pathogenesis of rotator cuff tear. The Dexamethasone(DEXA) is a synthetic corticosteroid. The purpose of this study was to examine the exact effect of dexamethasone on NF-κB signaling in rotator cuff tear. We measured NF-κB expression in four groups: control, TNF-α-treated, DEXA-treated, and combined treatment with TNF-α and DEXA. Tenocytes were isolated from patients with rotator cuff tears and pre-incubated with TNF-α (10 ng/ml), DEXA (1 µM), or both of them for 10 min, 1 h, and 2 h. Expression of p65, p50, and p52 in the nuclei and cytosol was analyzed by western blotting and immunofluorescence imaging using confocal microscopy. We also evaluated nucleus/cytosol (N/C) ratios of p65, p50, and p52. In our study, the combined treatment with DEXA and TNF-α showed increased N/C ratios of p65, p50, and p52 compared with those in the TNF-α group at all time points. Additionally, in the DEXA group, N/C ratios of p65, p50, and p52 gradually increased from 10 min to 2 h. In conclusion, DEXA promoted the nuclear localization of p65, p50, and p52, but was not effective in inhibiting the inflammatory response of TNF-α-stimulated rotator cuff tear.
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Dexametasona/farmacología , FN-kappa B/metabolismo , Lesiones del Manguito de los Rotadores/metabolismo , Transducción de Señal/efectos de los fármacos , Tenocitos/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Núcleo Celular/metabolismo , Células Cultivadas , Citosol/metabolismo , Humanos , Lesiones del Manguito de los Rotadores/patología , Tenocitos/metabolismoRESUMEN
Salt-leaching using powder (SLUP) scaffolds are novel salt-leaching scaffolds with well-interconnected pores that do not require an organic solvent or high pressure. In this study, in vitro and in vivo cell behaviors were assessed using a PCL (polycaprolactone) SLUP scaffold. Moreover, using PCL, conventional salt-leaching and 3D-plotted scaffolds were fabricated as control scaffolds. Morphology, mechanical property, water absorption, and in vitro/in vivo cell response assessments were performed to clarify the characteristics of the SLUP scaffold compared with control scaffolds. Consequently, we verified that the interconnectivity between the pores of the SLUP scaffold was enhanced compared with conventional salt-leaching scaffolds. Moreover, in vitro cell attachment and proliferation of the SLUP scaffold were higher than those of the 3D-plotted scaffold because of their morphological characteristic. Furthermore, we revealed that new bone formation and bone ingrowth of the SLUP scaffold was superior to those of the calvarial defect model and 3D-plotted scaffold because of the high porosity and improved interconnectivity of pores by the SLUP technique without high pressure using powders. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3432-3444, 2017.
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Regeneración Ósea , Poliésteres/química , Sales (Química)/administración & dosificación , Andamios del Tejido/química , Animales , Adhesión Celular , Proliferación Celular , Células Cultivadas , Ensayo de Materiales , Osteoblastos/citología , Porosidad , Polvos , Impresión Tridimensional , Ratas Sprague-Dawley , Cráneo/lesiones , Cráneo/fisiología , Ingeniería de TejidosRESUMEN
To enhance the mechanical properties of three-dimensional (3D) scaffolds used for bone regeneration in tissue engineering, many researchers have studied their structure and chemistry. In the structural engineering field, the kagome structure has been known to have an excellent relative strength. In this study, to enhance the mechanical properties of a synthetic polymer scaffold used for tissue engineering, we applied the 3D kagome structure to a porous scaffold for bone regeneration. Prior to fabricating the biocompatible-polymer scaffold, the ideal kagome structure, which was manufactured by a 3D printer of the digital light processing type, was compared with a grid-structure, which was used as the control group, using a compressive experiment. A polycaprolactone (PCL) kagome-structure scaffold was successfully fabricated by additive manufacturing using a 3D printer with a precision extruding deposition head. To assess the physical characteristics of the fabricated PCL-kagome-structure scaffold, we analyzed its porosity, pore size, morphological structure, surface roughness, compressive stiffness, and mechanical bending properties. The results showed that, the mechanical properties of proposed kagome-structure scaffold were superior to those of a grid-structure scaffold. Moreover, Sarcoma osteogenic (Saos-2) cells were used to evaluate the characteristics of in vitro cell proliferation. We carried out cell counting kit-8 (CCK-8) and DNA contents assays. Consequently, the cell proliferation of the kagome-structure scaffold was increased; this could be because the surface roughness of the kagome-structure scaffold enhances initial cell attachment.
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Técnicas de Cultivo de Célula , Poliésteres/química , Ingeniería de Tejidos , Andamios del Tejido/química , Regeneración Ósea , Adhesión Celular , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , ADN/química , Humanos , Ensayo de Materiales , Polímeros/química , Porosidad , Impresión Tridimensional , Estrés Mecánico , Propiedades de SuperficieRESUMEN
INTRODUCTION: Posterior locked lateral compression injury (PLLCI) of the pelvic ring is an infrequent variant of lateral compression injury, a condition described in only eight reported cases since 2000. Lateral compression injury usually results from high-energy trauma and is characterized by locking between the medially translated fractured ilium and the anterior border of the sacrum, regardless of whether the fractured ilium involves the sacroiliac joint. However, in our experience, lateral compression injury can also result from low-energy trauma as a manifestation of pelvic fragility fracture. The aim of the present study was to describe this rare form of PLLCI in a case series of geriatric patients. METHODOLOGY: A retrospective analysis of consecutive patients with pelvic ring injuries who were admitted to our hospital from January 2008 to April 2015 identified seven geriatric patients (1 male and 6 females; median age 81 years) with a form of PLLCI. RESULTS: All injuries were due to falls from a standing position onto the ground. All seven cases demonstrated characteristics of a locking fractured ilium over the anterior border of the sacrum on axial computed tomography images, but were not detected on plain radiographs. All underwent follow-up at 1 year or later with improved mean visual analogue scale scores (range 0-3). Regarding Koval walking ability scores, patients who underwent pelvic brim plating with anterior external fixation were more likely to regain their pre-injury walking ability than patients who only underwent anterior external fixation or conservative treatment. CONCLUSION: Geriatric patients can experience PLCCIs of the pelvis due to low-energy trauma. These fractures have different characteristics from those associated with severe injuries due to high-energy trauma, and they comprise an infrequent form of Rommens fragility fracture of the pelvis (type IIIa). In these cases, appropriate surgical management that includes sacroiliac plating combined with anterior external fixation can yield good outcomes.
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Fracturas Óseas/cirugía , Huesos Pélvicos , Pelvis , Accidentes por Caídas , Anciano , Anciano de 80 o más Años , Femenino , Fijación Interna de Fracturas , Humanos , Masculino , Huesos Pélvicos/lesiones , Huesos Pélvicos/cirugía , Pelvis/lesiones , Pelvis/cirugía , Estudios Retrospectivos , Sacro/lesiones , Sacro/cirugíaRESUMEN
In this study, the fabrication method was proposed for the well-interconnected polycaprolactone/hydroxyapatite composite scaffold with exposed hydroxyapatite using modified WNM technique. To characterize well-interconnected scaffolds in terms of hydroxyapatite exposure, several assessments were performed as follows: morphology, mechanical property, wettability, calcium ion release, and cell response assessments. The results of these assessments were compared with those of control scaffolds which were fabricated by precision extruding deposition (PED) apparatus. The control PED scaffolds have interconnected pores with nonexposed hydroxyapatite. Consequently, cell attachment of proposed WNM scaffold was improved by increased hydrophilicity and surface roughness of scaffold surface resulting from the exposure of hydroxyapatite particles and fabrication process using powders. Moreover, cell proliferation and differentiation of WNM scaffold were increased, because the exposure of hydroxyapatite particles may enhance cell adhesion and calcium ion release. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2315-2325, 2017.
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Proliferación Celular , Durapatita/química , Ensayo de Materiales , Poliésteres/química , Andamios del Tejido/química , Adhesión Celular , Línea Celular , HumanosRESUMEN
PURPOSE: To report the clinical and radiological outcomes of arthroscopic suture bridge repair for the GT fractures of the shoulder joint. METHODS: From March 2008 to July 2013, we performed arthroscopic suture bridge repair of the GT fractures displaced more than 5 mm superiorly or posteriorly, but less than 2 cm in 40 cases [20 men, 20 women; mean age, 56 (27-80) years] with the average 32 (24-48) months follow-up. At the final follow-up, clinical (ASES, UCLA, SST, KSS score and range of motions) and radiological outcomes using post-operative MRI or CT scan were evaluated. Associated injuries occurred in 21 cases (52.5%): 8 rotator cuff tears; 7 SLAP lesions; 3 glenoid rim fractures; 3 Bankart lesions; 5 biceps tendon tears; 1 partial subscapularis tear; 1 combined subscapularis and biceps tendon tear, and 1 brachial plexus injury. RESULTS: At the final follow-up, the mean VAS score improved from 7 to 1; ASES, to 92; UCLA, to 32; KSS, to 90; and SST, to 10. Mean forward flexion, abduction, external rotation at the side, and internal rotation at the back were improved to 157°, 157°, 37° and T11, respectively. Mean residual superior and posterior displacement of the fracture was 0 (range -5 to 3.3) mm and 0.1 (-5.5 to 3.2) mm, respectively, compared to pre-operative displacement of 4.9 (0-14) mm and 4.5 (0-20) mm, respectively (p < 0.001). Complications included anchor protrusion in five cases. CONCLUSION: Arthroscopic suture bridge repair was useful for the treatment of displaced GT fractures with or without comminution and the management of the combined lesions. At the final follow-up, meaningful remodeling of the GT fracture and satisfactory clinical outcomes could be achieved.