Objective To describe the disease characteristics of osteonecrosis of the femoral head (ONFH) in patients with systemic lupus erythematosus (SLE) who experiencing prolonged glucocorticoid (GC) exposure. Methods Between January 2016 and June 2019, 449 SLE patients meeting the criteria were recruited from multiple centers. Hip MRI examinations were performed during screening and regular follow-up to determine the occurrence of ONFH. The cohort was divided into ONFH and non-ONFH groups, and the differences in demographic baseline characteristics, general clinical characteristics, GC medication information, combined medication, and hip clinical features were compared and comprehensively described. ResultsThe age at SLE diagnosis was 29.8 (23.2, 40.9) years, with 93.1% (418 cases) being female. The duration of GC exposure was 5.3 (2.0, 10.5) years, and the cumulative incidence of SLE-ONFH was 9.1%. Significant differences (P<0.05) between ONFH and non-ONFH groups were observed in the following clinical characteristics: ① Demographic baseline characteristics: ONFH group had a higher proportion of patients with body mass index (BMI)<20 kg/m2 compared to non-ONFH group. ② General clinical characteristics: ONFH group showed a higher proportion of patients with cutaneous and renal manifestations, positive antiphospholipid antibodies (aPLs) and anticardiolipin antibodies, severe SLE patients [baseline SLE Disease Activity Index 2000 (SLEDAI-2K) score ≥15], and secondary hypertension. Fasting blood glucose in ONFH group was also higher. ③ GC medication information: ONFH group had higher initial intravenous GC exposure rates, duration, cumulative doses, higher cumulative GC doses in the first month and the first 3 months, higher average daily doses in the first 3 months, and higher proportions of average daily doses ≥15.0 mg/d and ≥30.0 mg/d, as well as higher full-course average daily doses and proportion of full-course daily doses ≥30.0 mg/d compared to non-ONFH group. ④ Combined medications: ONFH group had a significantly higher rate of antiplatelet drug use than non-ONFH group. ⑤ Hip clinical features: ONFH group had a higher proportion of hip discomfort or pain and a higher incidence of hip joint effusion before MRI screening than non-ONFH group. Conclusion The incidence of ONFH after GC exposure in China’s SLE population remains high (9.1%), with short-term (first 3 months), medium-to-high dose (average daily dose ≥15 mg/d) GC being closely associated with ONFH. Severe SLE, low BMI, certain clinical phenotypes, positive aPLs, and secondary hypertension may also be related to ONFH.
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.
Objective To evaluate the correlation between pelvic incidence (PI) angle, hip deflection angle (HDA), combined deflection angle (CDA) and osteonecrosis of the femoral head (ONFH) after femoral neck fracture, in order to explore early predictive indicators for ONFH occurrence after femoral neck fracture. Methods A study was conducted on patients with femoral neck fractures who underwent cannulated screw internal fixation between December 2018 and December 2020. Among them, 208 patients met the selection criteria and were included in the study. According to the occurrence of ONFH, the patients were allocated into ONFH group and non-NOFH group. PI, HDA, and CDA were measured based on the anteroposterior X-ray films of pelvis and axial X-ray films of the affected hip joint before operation, and the differences between the two groups were compared. The receiver operating characteristic curve (ROC) was used to evaluate the value of the above imaging indicators in predicting the occurrence of ONFH. ResultsAmong the 208 patients included in the study, 84 patients experienced ONFH during follow-up (ONFH group) and 124 patients did not experience ONFH (non-ONFH group). In the non-ONFH group, there were 59 males and 65 females, the age was 18-86 years (mean, 53.9 years), and the follow-up time was 18-50 months (mean, 33.2 months). In the ONFH group, there were 37 males and 47 females, the age was 18-76 years (mean, 51.6 years), and the follow-up time was 8-45 months (mean, 22.1 months). The PI, HDA, and CDA were significantly larger in the ONFH group than in the non-ONFH group (P<0.05). ROC curve analysis showed that the critical value of PI was 19.82° (sensitivity of 40.5%, specificity of 86.3%, P<0.05); the critical value of HDA was 20.94° (sensitivity of 77.4%, specificity of 75.8%, P<0.05); and the critical value of CDA was 39.16° (sensitivity of 89.3%, specificity of 83.1%, P<0.05). Conclusion There is a correlation between PI, HDA, CDA and the occurrence of ONFH after femoral neck fracture, in which CDA can be used as an important reference indicator. Patients with CDA≥39.16° have a higher risk of ONFH after femoral neck fracture.
ObjectiveTo explore the risk factors for osteonecrosis of the femoral head (ONFH) after treatment of femoral neck fractures with femoral neck system (FNS). MethodsBetween January 2020 and February 2021, 179 patients (182 hips) with femoral neck fractures treated by FNS fixation were selected for retrospective analysis. There were 96 males and 83 females with an average age of 53.7 years (range, 20-59 years). There were 106 cases of low-energy-induced injury and 73 cases of high-energy-induced injury. The fractures were classified as type Ⅱ in 40 hips, type Ⅲ in 78 hips, and type Ⅳ in 64 hips according to Garden classification standard, and as typeⅠin 23 hips, type Ⅱ in 66 hips, and type Ⅲ in 93 hips according to Pauwels classification standard. There were 21 patients with diabetes. Patients were divided into ONFH group and non-ONFH group according to whether ONFH occurred at last follow-up. The data of the patients were collected, including age, gender, body mass index (BMI), trauma mechanism, bone mineral density, having diabetes or not, Garden classification and Pauwels classification of fractures, fracture reduction quality, femoral head retroversion angle, and removal of internal fixator or not. The above factors were analyzed by univariate analysis, and then multivariate logistic regression analysis was used to identify risk factors. Results Total 179 patients (182 hips) were followed up 20-34 months (mean, 26.5 months). Of these, 30 cases (30 hips) developed ONFH at 9-30 months after operation (ONFH group), and the incidence of ONFH was 16.48%. And 149 cases (152 hips) had no ONFH at last follow-up (non-ONFH group). The univariate analysis showed that there were significant differences between groups in bone mineral density, having diabetes or not, Garden classification, femoral head retroversion angle, and fracture reduction quality (P<0.05). The multivariate logistic regression analysis showed that the Garden type Ⅳ fracture, reduction quality of grading Ⅲ, femoral head retroversion angle >15°, complicated with diabetes were the risk factors for ONFH after FNS fixation (P<0.05). ConclusionFor the patients with Garden type Ⅳ fracture, poor quality of fracture reduction, femoral head retroversion angle >15°, and diabetes, the risk of ONFH after FNS fixation increases.
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.
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 explore the feasibility and effectiveness of the modified transtrochanteric curved varus osteotomy in the treatment of osteonecrosis of the femoral head (ONFH), clarify the key points of the operation, and then explore the effectiveness of modified transtrochanteric curved varus osteotomy in the treatment of ONFH assisted by virtual reality (VR) technology. MethodsA 70-year-old adult female cadaver without formaldehyde fixation was taken. It was confirmed by anatomical study and simulated operation that the modified transtrochanteric curved varus osteotomy was suitable for type C1 (patients with involvement of the lateral column of the femoral head but partial integrity) classified by the Japanese Osteonecrosis Investigation Committee (JIC). Between October 2018 and August 2020, 11 patients (17 hips) with ONFH who met the selection criteria were treated with modified transtrochanteric curved varus osteotomy. VR technology was used to simulate varus osteotomy before operation to predict the angle of valgus of lower limbs and pronation of femoral head. Osteotomy, valgus, and pronation were performed according to the results of preoperative planning. After operation, X-ray films were used to evaluate the changes of varus and neck-shaft angle after VR assisted surgery, and Harris score was used to evaluate the hip function. ResultsThe anteroposterior pelvic X-ray film was rechecked at 2 days after operation, of which 3 hips were consistent with the planned varus angle of VR preoperative planning, and the error value of varus angle of the remaining 14 hips was 1°-4°. The difference between VR preoperative planning and 2 days after operation was 6°-16°. All 11 patients were followed up 11-28 months, with an average of 19.2 months. All incisions healed by first intension. During the follow-up, 1 case (1 hip) developed greater trochanter fracture at 2 months after operation and was treated with open reduction and plate and screw internal fixation; 1 case (1 hip) had delayed healing at osteotomy at 4 months after operation and healed at 3 months after local injection of platelet rich plasma and oral supplementation of kidney blood-strengthening soup. At last follow-up, 17 hip osteotomies healed. The Harris score was 84.0±5.6, which was significantly higher than that before operation (57.2±5.5) (t=–14.107, P=0.000); hip function was excellent in 2 hips, good in 13 hips, and fair in 2 hips. ConclusionThe modified transtrochanteric curved varus osteotomy for the treatment of ONFH is theoretically feasible, and the short-term effectiveness of this operation combined with VR technology is satisfactory.
ObjectiveTo review the research progress of subtype H vessels in the occurrence and development of osteonecrosis of the femoral head (ONFH).MethodsThe relevant domestic and foreign literature was extensively reviewed. The histological features, biological mechanism of subtype H vessels involved in promoting of osteogenesis, and the role and application of the subtype H vessels in ONFH were summarized.ResultsThe subtype H vessel is a newly discovered bone vessel, mainly distributed in metaphysis and subperiosteum, highly expressing endomucin and CD31. The subtype H vessel has a dense arrangement of Runx2+ early osteoprogenitors, collagen type Ⅰα+ osteoblast cells, and Osterix+ osteoprogenitors that have the ability to induce osteogenesis and angiogenesis. Factors such as platelet-derived growth factor BB, slit guidance ligand 3, hypoxia inducible factor 1α, Notch signaling pathway, and vascular endothelial growth factor are involved in the mechanism of subtype H vessels in promoting osteogenesis.ConclusionSubtype H vessels play an important role in the regulation of angiogenesis and osteogenesis during bone tissue repair and reconstruction. The discovery of subtype H vessels provides new insights into the molecular and cellular mechanisms of osteogenesis and angiogenesis coupling. In the future, new techniques targeting the regulation of subtype H blood vessels may become a promising method for the treatment of ONFH.
Objective To explore the impact of preoperative traction on the osteonecrosis of the femoral head (ONFH) in patients with femoral neck fractures. Methods Between February 2013 and May 2016, 120 patients with femoral neck fractures, who were treated with screw fixation, were collected. Sixty patients with fractures of Garden type Ⅰ and Ⅱ were non-displaced fracture group; 60 cases with fractures of Garden type Ⅲ and Ⅳ were displaced fracture group. The patients in 2 groups were randomly divided into traction and non-traction subgroups (n=30). There was no significant difference in gender, age, injury mechanism, damage side, the time from injury to operation, and fracture classification between 2 subgroups (P>0.05). Intracapsular pressure was recorded before operation. The quality of fracture reduction and the satisfaction ratio of screw implant were evaluated during operation. Visual analogue scale (VAS), Harris score, joint mobility, and the incidence of ONFH would be evaluated at 6 months, 1 year, and 2 years after operation. Results All incisions of 2 groups healed by first intention after operation. There was no infection or deep vein thrombosis of lower extremity. All patients were followed up 2 years. In displaced and non-displaced fracture groups, the intracapsular pressure of traction subgroups were higher than that of non-traction group (P<0.05); the differences of the quality of fracture reduction and the satisfaction ratio of screw implant were not significant (P>0.05) between 2 subgroups. At 6 months, 1 year, and 2 years after operation, VAS scores were higher in traction subgroup than in non-traction subgroup (P<0.05); and the joint mobility and Harris scores were lower in traction subgroup than in non-traction subgroup (P<0.05). X-ray films showed all fractures healed. Except for the non-displaced group at 6 months, the incidences of ONFH were higher in traction subgroup than in non-traction subgroup at other time points (P< 0.05). Conclusion Preoperative traction may increase the risk of ONFH, which can increase the intracapsular pressure and affect the blood supply of femoral head.
ObjectiveTo explore the effect of icariin on early steroid-induced osteonecrosis of the femoral head in rabbits.MethodsFifty mature New Zealand rabbits (weighing, 2.5-3.0 kg) were randomly divided into control group (n=10), model group (n=20), and experimental group (n=20). The rabbits of model and experimental groups were injected with lipopolysaccharide and methylprednisolone to establish the animal model of early steroid-induced osteonecrosis of the femoral head. The rabbits of experimental group were feeded with icariin solution once a day for 6 weeks since the first injection of methylprednisolone, whereas the rabbits of control and model groups were given normal saline at the same time points. The left femoral heads were removed after 6 weeks and gross morphological features were evaluated. Micro-CT scan was performed to analyze the trabecular microstructure with the following parameters: trabecular bone volume to total volume (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Tn), and trabecular separation (Tb.Sp). The Micro-CT scan was also converted to three-dimensional reconstruction images for observation. HE staining was applied to observe the trabecular structure and morphological changes of osteocytes and marrow adipocytes. It was also used to determine whether the samples of femoral heads occurred osteonecrosis based on the criteria for pathological diagnosis, and calculate the rate of empty lacunae.ResultsSeven rabbits died during the study, and 9, 16, and 18 rabbits in the control, model, and experimental groups, respectively, enrolled the final analysis. Compared with control group, the femoral head collapse and trabecular breaks were more obvious, and the trabeculae were sparse with irregular arrangement in the model group according to the results of gross observation, Micro-CT scan, and three-dimensional reconstruction images. But in the experimental group, the surface of femoral head was slight shrinking without obvious collapse, and the degeneration of trabecular structure was mild. According to bone microstructures analysis, the Tb.N, Tb.Tn, and BV/TV of femoral head in model and experimental groups were lower than those in control group, while the Tb.Sp in the model and experimental groups were significantly higher. The Tb.N, Tb.Tn, and BV/TV of femoral head in experimental group were higher than those in model group, while the Tb.Sp in the experimental group was significantly lower. The differences between groups were all significant (P<0.05). In the model group, HE staining showed that the number of osteocytes reduced, the number of empty lacunae increased, and the marrow adipocytes piled up in the space between femoral trabeculae, some even mashed together like a cyst. In the experimental group, the trabecular structure was still relatively complete compared with model group, no obvious apoptosis of osteocytes was observed, the size and number of adipocytes were basically normal. None of the animals in control group occurred osteonecrosis of the femoral head based on the criteria for pathological diagnosis, and the incidence of osteonecrosis were 81.3% (13/16) in the model group and 66.7% (12/18) in the experimental group, and the difference was not significant (P=0.448). The rate of empty lacunae of osteonecrotic femoral heads in the model group was 33.1%±1.4%, which was higher than that in experimental group (18.9%±0.8%) and in control group (12.7%±1.5%), and the differences between groups were significant (P<0.05).ConclusionThe icariin has a protective effect on the early steroid-induced osteonecrosis of the femoral head in rabbits, which can decrease osteocytes apoptosis, improve the bone microstructure, and delay such disease processes.