ObjectiveTo explore the effect of Kaempferol on bone microvascular endothelial cells (BMECs) in glucocorticoid induced osteonecrosis of the femoral head (GIONFH) in vitro. MethodsBMECs were isolated from cancellous bone of femoral head or femoral neck donated voluntarily by patients with femoral neck fracture. BMECs were identified by von Willebrand factor and CD31 immunofluorescence staining and tube formation assay. The cell counting kit 8 (CCK-8) assay was used to screen the optimal concentration and the time point of dexamethasone (Dex) to inhibit the cell activity and the optimal concentration of Kaempferol to improve the inhibition of Dex. Then the BMECs were divided into 4 groups, namely, the cell group (group A), the cells treated with optimal concentration of Dex group (group B), the cells treated with optimal concentration of Dex+1 μmol/L Kaempferol group (group C), and the cells treated with optimal concentration of Dex+5 μmol/L Kaempferol group (group D). EdU assay, in vitro tube formation assay, TUNEL staining assay, Annexin Ⅴ/propidium iodide (PI) staining assay, Transwell migration assay, scratch healing assay, and Western blot assay were used to detect the effect of Kaempferol on the proliferation, tube formation, apoptosis, migration, and protein expression of BMECs treated with Dex. ResultsThe cultured cells were identified as BMECs. CCK-8 assay showed that the optimal concentration and the time point of Dex to inhibit cell activity was 300 μmol/L for 24 hours, and the optimal concentration of Kaempferol to improve the inhibitory activity of Dex was 1 μmol/L. EdU and tube formation assays showed that the cell proliferation rate, tube length, and number of branch points were significantly lower in groups B-D than in group A, and in groups B and D than in group C (P<0.05). TUNEL and Annexin V/PI staining assays showed that the rates of TUNEL positive cells and apoptotic cells were significantly higher in groups B-D than in group A, and in groups B and D than in group C (P<0.05). Scratch healing assay and Transwell migration assay showed that the scratch healing rate and the number of migration cells were significantly lower in groups B-D than in group A, and in groups B and D than in group C (P<0.05). Western blot assay demonstrated that the relative expressions of Cleaved Caspase-3 and Bax proteins were significantly higher in groups B-D than in group A, and in groups B and D than in group C (P<0.05); the relative expressions of matrix metalloproteinase 2, Cyclin D1, Cyclin E1, VEGFA, and Bcl2 proteins were significantly lower in groups B-D than in group A, and in groups B and D than in group C (P<0.05). Conclusion Kaempferol can alleviate the damage and dysfunction of BMECs in GIONFH.
ObjectiveTo analyse the effectiveness of unicompartmental knee arthroplasty (UKA) for the patients with spontaneous osteonecrosis of the knee (SONK). MethodsBetween January 2012 and December 2016, 31 patients with SONK was admitted and treated with medial UKA. All patients were examined by both plain radiography and magnetic resonance images. The patients were composed of 5 men and 26 women with an average age of 64.3 years (range, 48-79 years), and with 16 left joints and 15 right joints. The average disease duration was 14.7 months (range, 6-26 months). Preoperative visual analogue scale (VAS) was 6.00±1.15, Hospital for Special Surgery (HSS) score was 55.77±11.03, and knee range of motion (ROM) was (114.68±10.40)°. The imaging examinations showed that all the lesions were located in the medial compartment of the knee joint and there were 19 patients with Aglietti stage Ⅳ and 12 patients with Aglietti stage Ⅴ. Preoperative femorotibial angle (FTA) was (177.39±1.63)° and posterior tibial slope (PTS) was (84.05±1.39)°. ResultsAll the incisions healed by first intention. All patients were followed up 14-46 months (mean, 25 months). At last follow-up, VAS score was 2.06±0.72 and HSS score was 86.45±3.67, which both improved significantly when compared with preoperative scores (t=22.73, P=0.00; t=–14.72, P=0.00). ROM was (118.06±3.80)° with no significant difference when compared with preoperative ROM (t=–1.78, P=0.08). The X-ray films showed there was no severe adverse events, such as periprosthetic infection, aseptic loosening, bearing dislocation, and so on. At last follow- up, PTS was (85.30±1.19)° with significant difference compared with preoperative one (t=–4.07, P=0.00); while FTA was (177.51±1.98)° with no significant difference when compared with preoperative FTA (t=–0.38, P=0.71). ConclusionUKA may be an optional management for SONK with minimally invasive, bone-preserving, and rapid recovery.
ObjectiveTo observe the volume and distribution of necrotic tissue of femoral head in steroid-induced osteonecrosis of femoral head (SONFH) patients by three-dimensional reconstruction of CT.MethodsA clinical data of 25 patients with SONFH between September 2016 and December 2018 was analyzed. There were 22 males and 3 females, with an average age of 38.8 years (range, 20-63 years). The necrosis of the femoral head was in stage Ⅱ of Association Research Circulation Osseous (ARCO). The disease duration ranged from 3 to 18 months, with an average of 9.2 months. A three-dimensional reconstruction with CT data of SONFH patients were performed by Mimics Research 21.0 software and the femoral head was segmented into eight regions by 3-matic Research 13.0 software. The volume of necrotic tissue of the femoral head and the volume rate of necrotic tissue to femoral head were calculated and the distribution was also analyzed.ResultsThe three-dimensional digital model of the femoral head showed that the necrotic tissue of the femoral head was located above the anterior superior medial, and the area of the necrotic tissue was in a dome-like shape. The results showed that the necrotic tissue in the femoral head was mainly concentrated on the anterior superior internal area, the anterior superior outer area, and the posterior superior internal area. The volume of femoral head was (48 399.52±9 408.90) mm3, and the volume of necrotic tissue was (20 917.08±6 566.94) mm3, and the volume ratio of necrotic tissue to femoral head was 44.75%±15.72%. The proportion of necrotic volume in different regions was different, and the necrotic tissues were mainly distributed in the anterior superior internal area, the anterior superior outer area, and the posterior superior internal area.ConclusionThe volume and distribution of necrotic tissue in femoral head can be evaluated quickly and intuitively by three-dimensional reconstruction of CT in Mimics software.
ObjectiveTo screen for the differentially expressed genes in steroid-induced osteonecrosis of the femoral head (ONFH) by gene microarray.
MethodsThe femoral head tissue of ONFH was harvested from 3 patients with steroid-induced ONFH, aged 25, 31, and 38 years, respectively. Normal tissue was harvested from a 26-year-old male remains contributor. HE staining of the specimens was performed for observing the histology manifestation; the total RNA was extracted for measuring the purity; cDNA probe was synthesized by reverse transcription, and then were hybridized as the cDNA microarray for scanning of fluorescent signals and differentially expressed genes in the tissues.
ResultsHE staining of normal tissue showed complete unit composed of lamellar bone, continuous and complete lamellar bone with a concentric arrangement around blood vessels, and normal bone cells in the trabecular bone lacuna. In ONFH tissue, adipose tissue increased in the medullary cavity, with increased fat cells filling in the medullary cavity and extruding capillary, and with decreased bone cells in the bone trabecula, which had deeply-stained nuclear chromatin, pyknotic or cracking nucleus, and even bone cells disappeared in the part of the bone lacuna, and trabecular bone became thin, sparse, interrupt, reduced area in visual field/unit. Total RNA extraction electrophoretogram displayed clear bands of 28S and 18S, and the brightness ratio of the 28S:18S was 2:1, indicating good total RNA quality. And 44 genes were differentially expressed, and there were 28 up-regulated genes and 16 down-regulated genes, including cell/organism defense genes, cell structure/motility genes, cell division genes, cell signaling/cell communication genes, cell metabolism genes, gene/protein expression genes, and unclassified genes.
ConclusionThe analysis of the gene expression profile of steroid-induced ONFH can provide evidence for the pathogenesis of ONFH.
【Abstract】 Objective The present study employed both static and dynamic imaging modal ities to study bothintra- and extravascular events attributing to steroid-associated osteonecrosis (ON) using an experimental protocol with a single low-dose l i ppolysaccharide (LPS) injection and subsequently three injections of high-dose methylprednisolone (MPS). Methods Fourteen 28-week-old male New Zealand white rabbits received one intravenous injection of LPS (10 μg/ kg). After 24 hours, three injections of 20 mg/kg of MPS were given intramuscularly at a time interval of 24 hours. Additional 6 rabbits were used as controls. Dynamic MRI was performed on bilateral femora for local intraosseous perfusion before and after LPS injection. Blood samples were collected for haematological examinations before and after LPS injection. Bilateral femora were dissected and decalcified for microCT-based microangiography. ON lesion, intravascular thrombus and extravascular marrow fat cell size were examined histopathologically. Results Intravascular thrombus was observed in all ON rabbits. Extravascular marrow fat cell size was significantly increased in ON rabbits than that of the controls (P lt; 0.05). Compared to basel ine, a significant decrease in ratio of tissue-type-plasminogen-activator/plasminogen-activator inhibitor 1,activated-partial- thromboplatin-time, and a significant increase in ratio of low-density-l ipoprotein/high-density-l ipoprotein were only found in ON rabbits (P lt; 0.05). Dynamic MRI showed a significant decrease in the perfusion index ‘maximum enhancement’ in the ON rabbits (P lt; 0.05) and microCT-based microangiography showed blocked stem vessels in ON samples.Overall, 93% of the rabbits (13/14) developed ON and no rabbits died throughout the experiment period. Conclusion Bothintra- and extravascular events were found attributing to the steroid- associated ON based on our experimental protocol with a single low-dose LPS injection and subsequent three injections of high-dose MPS. Both high ON incidence and no mortal ity in rabbits treated with this inductive protocol suggested its effectiveness for future studies on evaluation of therapeutic efficacy of interventions developed for prevention of steroid-associated ON.
Objective To evaluate the effectiveness of medial buttress plate augmented hollow lag screws fixation in combination with sartorius pedicled iliac flap for the treatment of femoral neck fractures in young adults. MethodsThe clinical data of 11 young adult patients with femoral neck fractures between February 2013 and February 2019 were analyzed retrospectively. There were 7 males and 4 females with a mean age of 45 years (range, 32-58 years). Fractures were caused by falling from height in 6 cases, by traffic accident in 4 cases, and by sports injury in 1 case. There were 7 cases in the left hip and 4 cases in the right hip. The mean Pauwels angle was 64° (range, 55°-75°). All patients were treated by medial buttress plate augmented hollow lag screws fixation and sartorius pedicled iliac flap. The X-ray film of pelvis, lateral X-ray film of hip joint, CT scan and three-dimensional reconstruction of hip joint were taken after operation to assess fracture healing and position of the internal fixators. The postoperative hip function was evaluated according to the Harris score. Results All the incisions healed by first intention, and no complication such as incision infection and lateral femoral cutaneous nerve injury happened. Re-examination on the second day after operation showed that reduction and fixation of fractures was good. All patients were followed up 18-36 months (mean, 29 months). All fractures achieved bony union. The time of bony union was 16-23 weeks, with an average of 18.2 weeks. One patient (9.1%) got osteonecrosis of the femoral head (ONFH) at 30 months after operation. At last follow-up, Harris score was used to evaluate hip joint function, 9 cases were excellent, 1 case was good, 1 case was fair, and the excellent and good rate was 90.9%. Conclusion Medial buttress plate augmented hollow lag screws fixation in combination with sartorius pedicled iliac flap for the treatment of femoral neck fractures in young adults has the advantage of strong biomechanical stability and can effectively improve the blood supply of femoral head and neck, which subsequently reduce the incidence of ONFH. However, the surgical indication should be fully considered.
Objective To explore the significance of osteocyte apoptosis in steroidinduced osteonecrosis of the femoral head. Methods SixtyNew Zealand rabbits were divided into experimental group and control group(n=30). The experimental group was given 10 ml/kg of horse serum intravenously 2 times at 2 weeks intervals and an intraperitoneal injection of 45 ml/kg·d of methylprednisolone acetate for 3 days；the control group was given equal isotonic Na chloride. Osteocyteapoptosis was observe by means of TUNEL. Results The number of apoptosis in the experimental group(112.33‰±26.12‰) was significantly higher than that in the control(47.01‰±22.95‰) (Plt;0.01)in the 4th week. With time, osteocytes apoptosis progressively increased. In the 6thand 8th weeks, the percentage of empty osteocyte lacunae in the experimental group (17.23%±3.44%, 28.56%±3.45%) was significantly higher than that in the control group (11.29%±2.89%,11.26%±2.75%，Ｐlt;0.05). The transmission electron microscope showed that the characteristics of osteocyte apoptosisincluded intact nuclear membrane,comdensed chromatin and increased electron dense. Conclusion Osteocytes apoptosis may play a key role in the process of steroidinduced early osteonecrosis of the femoral head.
ObjectiveTo investigate whether exosomes derived from miR-27a-overexpressing human umbilical vein endothelial cells (HUVECs)—exo (miR-27a) can promote bone regeneration and improve glucocorticoids (GC) induced osteonecrosis of femoral head (ONFH) (GC-ONFH).MethodsThe exo (miR-27a) were intended to be constructed and identified by transmission electron microscopy, nanoparticle tracking analysis, Western blot, and real-time fluorescent quantitative PCR (qRT-PCR). qRT-PCR was used to evaluate the effect of exo (miR-27a) in delivering miR-27a to osteoblasts (MC3T3-E1 cells). Alkaline phosphatase staining, alizarin red staining, and qRT-PCR were used to evaluate its effect on MC3T3-E1 cells osteogenesis. Dual-luciferase reporter (DLRTM) assay was used to verify whether miR-27a targeting Dickkopf WNT signaling pathway inhibitor 2 (DKK2) was a potential mechanism, and the mechanism was further verified by qRT-PCR, Western blot, and alizarin red staining in MC3T3-E1 cells. Finally, the protective effect of exo (miR-27a) on ONFH was verified by the GC-ONFH model in Sprague Dawley (SD) rats.ResultsTransmission electron microscopy, nanoparticle tracking analysis, Western blot, and qRT-PCR detection showed that exo (miR-27a) was successfully constructed. exo (miR-27a) could effectively deliver miR-27a to MC3T3-E1 cells and enhance their osteogenic capacity. The detection of DLRTM showed that miR-27a promoted bone formation by directly targeting DDK2. Micro-CT and HE staining results of animal experiments showed that tail vein injection of exo (miR-27a) improved the osteonecrosis of SD rat GC-ONFH model.Conclusionexo (miR-27a) can promote bone regeneration and protect against GC-ONFH to some extent.
Objective
To review the research progress of alcohol-induced osteonecrosis of the femoral head (ONFH).
Methods
Recent literature concerning alcohol-induced ONFH was reviewed and summarized.
Results
Alcohol-induced ONFH accounte for approximately 1/3 of total ONFH. Alcohol intake and the incidence of ONFH has a significant dose-effect relationship. There are some correlations between alcohol-induced ONFH and lipid metabolism, secretion of corticosteroid, and some gene of alcohol or lipid metabolism.
Conclusion
The relationships between alcohol and lipid metabolism, and between alcohol and steroid are still the main direction of the research of ONFH. Gene level researches can not demonstrate the pathogenesis, therefore further research should be carried on.
Objective To summarize the characteristics and clinical significance of irreducible Pipkin type Ⅰ and Ⅱ femoral head fracture-dislocations. Methods The clinical data of 4 patients with irreducible Pipkin type Ⅰ and Ⅱ femoral head fracture-dislocations between January 2010 and December 2019 were collected. There were 2 males and 2 females and the age ranged from 24 to 41 years, with an average age of 33.5 years. The cause of injury included traffic accident in 3 cases and falling in 1 case. Pipkin classification was 2 cases of type Ⅰ and 2 cases of type Ⅱ. The time from injury to operation was 1-2 days. The clinical features were that the hip joint of the affected limb was in a locked position, and the passive range of motion was poor. The affected limb was slightly flexed at the hip joint and shortened, in a state of neutral position or slight adduction and internal rotation. The imaging data suggested that the femoral head dislocated backward and upward, and the hard cortex of the posterior edge of the acetabulum was embedded in the cancellous bone of the femoral head, and the two were compressed and incarcerated. Patients of cases 1-3 underwent closed reduction of hip dislocation 1-2 times at 3, 1, and 3 hours after injury respectively, and femoral neck fracture occurred. The injury types changed to Pipkin type Ⅲ, and open reduction and internal fixation were performed. Patient of case 4 did not undergo closed reduction, but underwent open reduction and internal fixation directly. Results Patients of cases 1-3 were followed up 14, 17, and 12 months, respectively. They developed osteonecrosis of the femoral head at 9, 5, and 10 months after operation respectively, and all underwent total hip arthroplasty. Patient of case 4 was followed up 24 months and had no hip pain and limited mobility; the imaging data indicated that the internal fixator position was good and the fracture healed; no collapse or deformation of the femoral head was seen, and no osteonecrosis of the femoral head occurred. Conclusion Clinicians need to improve their understanding of the unique clinical features and imaging findings of irreducible Pipkin type Ⅰ and Ⅱ femoral head fracture-dislocations. It is suggested that open reduction and simultaneous fixation of femoral head fracture should be directly used to reduce the incidence of osteonecrosis of the femoral head.
