Predicting fracture classification and prognosis with hounsfield units and femoral cortical index: A simple and cost-effective approach.

BACKGROUND: The relationship between bone density and fracture has been widely studied and recognized, and the role of cortical bone in proximal femoral fractures has also been increasingly studied. However, both the determination of bone mineral density (BMD) and the determination of cortical mass are expensive and cumbersome. The purpose of this study is to investigate whether two readily available indicators, Hounsfield Units (HUs) and femoral cortical index (FCI), can be used to predict hip fracture classification and prognosis. METHODS: A retrospective study was conducted on 110 patients with hip fragility fractures. Cortical index was calculated on fractured and contralateral femur FCI, with HUs calculated on the proximal femur. The correlation of the FCI and HU with diabetes, hypertension, and related indicators, such as albumin, creatinine, and urea nitrogen levels, were also analyzed in the study. RESULTS: Both the Evans classification of intertrochanteric fractures and the Garden and Pauwels classifications of femoral neck fractures showed that as the severity of the fracture increased, the HUs and FCI decreased. Age and albumin level also had a negative correlation with HUs and FCI. There was also a significant correlation between HUs and FCI. CONCLUSIONS: The HUs and FCI, which can be easily and quickly obtained, can be used to predict the classification and prognosis of hip fractures.

Preoperative Computed Tomography in Guiding the Length of Cannulated Screws in Medial Malleolar Fractures.

Excessive lengths of partially threaded cannulated screws in medial malleolus fractures are often related to failure of fixation. This study aimed to analyze the distribution and density of cancellous bone in the medial malleolus among healthy individuals and provide a theoretical basis for determining the lengths of cannulated screws based on preoperative computed tomography (CT) to achieve stable fixation of medial malleolus fractures. Between January 2012 and December 2016, 100 patients (without ankle fractures) who underwent computed tomography of the distal tibia were included. Specific levels on the computed tomography images were selected to assess the density and length of valid cancellous bone in the medial malleolus. Meanwhile, we followed up 44 patients who underwent open reduction and internal fixation of medial malleolus fractures based on preoperative computed tomography-based measurements. The valid lengths of cancellous bone in the medial malleolus were significantly different between men and women (p < .05). In addition, there was a significant difference among different age groups (p < .05). All patients were followed up to union without displacement. Age and gender have a considerable impact on the distribution and density of cancellous bone in the medial malleolus. The density and length of valid cancellous bone decrease with age. The shoulder of the tibial plafond in medial malleolus, which is a weak part of cancellous bone, is a common site of fracture. Short screws are recommended for fixation in elderly patients. In conclusion, preoperative computed tomography can help determine the length and location of cannulated screws.

Quercetin attenuates oxidative stress-induced apoptosis via SIRT1/AMPK-mediated inhibition of ER stress in rat chondrocytes and prevents the progression of osteoarthritis in a rat model.

Apoptosis of chondrocytes are the main initiator of osteoarthritis (OA) and can be explained by oxidative stress and endoplasmic reticulum (ER) stress, thus the pharmacological interventions aimed at inhibiting of these pathways may be a promising approach for the management of OA. Quercetin is a member of the flavonoid family and has antioxidant and anti-inflammatory properties in degenerative diseases. However, its effects and potential mechanisms on the pathological process of OA are not very clear. The present study aimed to investigate the protective effects of quercetin on OA and the underlying mechanisms. The tert-butyl hydroperoxide (TBHP)-stimulated rat chondrocytes and destabilization of the medial meniscus OA rat model was used to explore the protective effects of quercetin. Our results showed that quercetin treatment can attenuate oxidative stress, ER stress, and associated apoptosis. Moreover, quercetin inhibited ER stress through activating the sirtuin1/adenosine monophosphate-activated protein kinase (SIRT1/AMPK) signaling pathway. The protective effects of quercetin were also observed in OA rat model which is evidenced by abolished cartilage degeneration and decreased chondrocytes apoptosis in the knee joints. Our results suggested that quercetin is a promising treatment for OA.

Reliability and Validity Analysis of Pelvic Sagittal Inclination Calculated by Inverse Cosine Function Method on Pelvic Anteroposterior Radiographs.

OBJECTIVE: Evaluation of sagittal pelvic tilt is significant for hip surgeons. However, the accurate measurement of pelvic sagittal inclination (PSI) is still a challenge. The objective of this study is to propose a new method for measurement of PSI from pelvic anteroposterior radiograph based on the inverse cosine function obtained from individualized pelvic model. METHODS: Collecting the imaging data of 30 patients with both pelvic CT and full-length spine radiographs. Establishing pelvic model by customized 3D reconstruction software. The length of three groups of longitudinal and transverse line segments (A'p and B') were measured from full-length spine anteroposterior radiographs. The corresponding anatomical parameters, including A, B, b, ∠α, ∠γ, were measured and calculated on the same patient's pelvic model. The estimated PSI (ePSI) based on three groups of anatomical landmarks, including ePSI-1, ePSI-2, and ePSI-3, were calculated by equation, ePSI = arccos A ' p b * B ' - ∠ α , and compared with the actual PSI (aPSI) measured by Surgamap software. For the reliability and validation evaluation, three observers measured these parameters in two rounds. Intra-class correlation and inter-class correlation were both calculated. Bland-Altman method was used to evaluate the consistency between the estimated PSI (ePSI) and the actual PSI (aPSI). RESULTS: ePSI-1 and ePSI-2 showed excellent intra-observer reliability (0.921-0.997, p < 0.001) and inter-observer reliability (0.801-0.977, p < 0.001). ePSI-3 had a fair inter-observer reliability (0.239-0.823, p < 0.001). ePSI-1 showed the strongest correlation with aPSI (r = 0.917, p < 0.001). Mean (maximum) absolute difference of ePSI-1, ePSI-2, and ePSI-3 is 2.62° (7.42°), 4.23° (13.78°), and 7.74° (31.47°), respectively. The proportion of cases with absolute difference less than 5° in three groups were 86.7% (ePSI-1), 66.7% (ePSI-2), 56.7% (ePSI-3). CONCLUSION: This new method based on inverse cosine function has good reliability and validity when used in the evaluation of PSI on pelvic anteroposterior radiographs.

Anti-Apoptosis and Autophagy Effects of Melatonin Protect Rat Chondrocytes against Oxidative Stress via Regulation of AMPK/Foxo3 Pathways.

OBJECTIVE: Emerging evidence has indicated that excessive reactive oxygen species (ROS) have detrimental effects on osteoarthritis (OA). This study aimed to elucidate the effects of melatonin (MT), an antioxidant indolamine secreted from the pineal gland, on chondrocyte senescence and cartilage degeneration, thereby clarifying the underlying mechanisms of ROS-induced OA pathogenesis. DESIGN: Hydrogen peroxide (H2O2) was used to induce oxidative stress in rat chondrocytes. ROS levels were evaluated using cytometry and immunofluorescence. Cell viability was detected using the Cell Counting Kit-8 (CCK-8) assay. Western blotting and qPCR (Quantiative Real-Time Polymerase Chain Reaction) were used to examine apoptosis and autophagy. For in vivo experiments, male Sprague-Dawley rats were randomly divided into a sham-operated group, DMM (destabilization of the medial meniscus) surgery group, and surgery groups that received melatonin. Knee joints were collected and stained for histological analysis. RESULTS: The data demonstrated that melatonin treatment significantly suppressed H2O2-induced matrix degradation and apoptosis, and maintained mitochondrial redox homeostasis. In addition, an enhancement of autophagic flux was observed through western blotting. These findings corresponded with activation of the AMPK/Foxo3 signaling pathways upon melatonin treatment. Histological staining and transmission electron microscopy (TEM) micrographs also demonstrated that melatonin alleviated cartilage ossification and chondrocyte hypertrophy in vivo. CONCLUSIONS: Our results indicated that melatonin protected chondrocytes via mitochondrial redox homeostasis and autophagy. The effects of melatonin on senescence may apply to other age-related diseases. Thus, melatonin may have multiple potential therapeutic applications.

Effect of surface preparation on the failure load of a highly filled composite bonded to the polymer-monomer matrix of a fiber-reinforced composite.

PURPOSE: The purpose of the present study was to evaluate the effect of surface preparation on the maximum fracture load value of a highly filled composite bonded to the polymer-monomer matrix of a fiber-reinforced composite. MATERIALS AND METHODS: A polymer-monomer matrix was made by mixing urethane dimethacrylate and triethyleneglycol dimethacrylate at a ratio of 1:1 with camphorquinone and 2-dimethylaminoethyl methacrylate as a light initiator. The matrix was then polymerized in a disk-shaped silicone mold with a light-polymerizing unit. The flat surfaces of the polymer-monomer matrix disk were prepared in one of the following ways: (1) without preparation; (2) application of silane coupling agent; or (3) application of matrix liquid and prepolymerization. A highly filled composite material was applied and polymerized with a light-polymerizing unit. Additional test specimens made entirely of the polymer-monomer matrix were fabricated as references; the disk and cylinder were fabricated in one piece using a mold specially made for the present study (group 4). Half the specimens were thermocycled up to 10,000 times in water with a 1-minute dwell time at each temperature (5 degrees C and 55 degrees C). The maximum fracture load values were determined using a universal testing machine (n = 10). RESULTS: The maximum fracture loads for group 3 were significantly enhanced both before and after thermocycling, whereas the maximum fracture loads of group 2 were significantly enhanced before thermocycling (p < 0.05); however, the failure loads decreased for all groups after thermocycling (p < 0.05). All the specimens in groups 1 and 2 debonded during thermocycling. The failure load of group 3 was significantly lower than that of group 4 both before and after thermocycling (p < 0.05). CONCLUSION: Within the limitations of the current in vitro study, the application and prepolymerization of a mixed dimethacrylate resin liquid prior to the application of a highly filled composite was an effective surface preparation for the polymer-monomer matrix of a fiber-reinforced composite; however, the bond durability may be insufficient.

Curcumin Inhibits the PERK-eIF2α-CHOP Pathway through Promoting SIRT1 Expression in Oxidative Stress-induced Rat Chondrocytes and Ameliorates Osteoarthritis Progression in a Rat Model.

Oxidative stress plays a crucial role in the occurrence and development of osteoarthritis (OA) through the activation of endoplasmic reticulum (ER) stress. Curcumin is a polyphenolic compound with significant antioxidant and anti-inflammatory activity among various diseases. To elucidate the role of curcumin in oxidative stress-induced chondrocyte apoptosis, this study investigated the effect of curcumin on ER stress-related apoptosis and its potential mechanism in oxidative stress-induced rat chondrocytes. The results of flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining showed that curcumin can significantly attenuate ER stress-associated apoptosis. Curcumin inhibited the expression of cleaved caspase3, cleaved poly (ADP-ribose) polymerase (PARP), C/EBP homologous protein (CHOP), and glucose-regulated protein78 (GRP78) and upregulated the chondroprotective protein Bcl2 in TBHP-treated chondrocytes. In addition, curcumin promoted the expression of silent information regulator factor 2-related enzyme 1 (SIRT1) and suppressed the expression of activating transcription factor 4 (ATF4), the ratio of p-PERK/PERK, p-eIF2α/eIF2α. Our anterior cruciate ligament transection (ACLT) rat OA model research demonstrated that curcumin (50 mg/kg and 150 mg/kg) ameliorated the degeneration of articular cartilage and inhibited chondrocyte apoptosis in ACLT rats in a dose-dependent manner. By applying immunohistochemical analysis, we found that curcumin enhanced the expression of SIRT1 and inhibited the expression of CHOP and cleaved caspase3 in ACLT rats. Taken together, our present findings firstly indicate that curcumin could inhibit the PERK-eIF2α-CHOP axis of the ER stress response through the activation of SIRT1 in tert-Butyl hydroperoxide- (TBHP-) treated rat chondrocytes and ameliorated osteoarthritis development in vivo.

Bonding of autopolymerizing acrylic resins to magnetic stainless steel alloys using metal conditioner.

OBJECTIVES: The shear bond strengths of a barbituric acid derivative-activated autopolymerizing acrylic resin to two magnetic stainless steel alloys using a metal conditioner were investigated. METHODS: The surfaces of the two magnetic stainless steel alloys were abraded with 600-grit silicon carbide paper. The surface preparations were: Group 1 (without preparation), Group 2 (airborne particle abrasion with 50 microm alumina), and Group 3 (airborne particle abrasion followed by priming with a metal conditioner). The alloys were bonded with a barbituric acid derivative-activated autopolymerizing acrylic resin. For comparison, airborne particle abrasion and bonding with a tri-n-butylborane-initiated autopolymerizing acrylic resin (Group 4), as well as airborne particle abrasion followed by priming with a metal conditioner and bonding with the same resin (Group 5) were added. Half of the specimens were thermocycled up to 10,000 cycles. The shear bond strengths were determined. RESULTS: Group 3 had significantly improved shear bond strengths with the barbituric acid derivative-activated autopolymerizing acrylic resin to both stainless steel alloys. Although there were no significant differences in the bond strength among Groups 3-5 before thermocycling, the decrease in the bond strength of Group 3 was considerably greater than that of Groups 4 or 5 after thermocycling for both stainless steel alloys. CONCLUSIONS: Significant improvements in the bond strength of the barbituric acid derivative-activated autopolymerizing acrylic resin to two magnetic stainless steel alloys were achieved by airborne particle abrasion followed by priming with the metal conditioner. The bond durability to this resin, however, was inferior to that to a tri-n-butylborane-initiated autopolymerizing acrylic resin.