Current concepts on osteonecrosis of the femoral head

Survival Analysis after Core Decompression in Association with Platelet-Rich Plasma, Mesenchymal Stem Cells, and Synthetic Bone Graft in Patients with Osteonecrosis of the Femoral Head

Purpose  The aim of this study was to report the rate of survivorship in patients with osteonecrosis of the femoral head treated with core decompression in association with mesenchymal stem cells (MSCs) implantation, platelet-rich plasma (PRP) injection, and synthetic bone graft. Methods  We evaluated 24 hips in 16 patients, according to Ficat classification, treated by core decompression, injection of PRP and MSCs, and backfilling of the core tract with synthetic bone graft. Survivorship was estimated using Kaplan-Meier curves. Results  The survivorship of core decompression in association with the procedure is 50% at 75 months of follow-up. The survival rate was 80% for patients in early stage and 28.6% for patients in advanced stage at 75 months. When we compared Kaplan-Meier survival curves of patients in stage III + IV and patients in stage I + II, we noticed that the survival functions are statistically different ( p  < 0.05, log-rank test), particularly in stage I + II where we had a greater surviving core decompression, in comparison to patients in stage III + IV. Conclusion  This technique is safe and good preliminary results were obtained in patients with early stages of the disease with no reported complications. Level of Evidence  Level IV, therapeutic case series.

The biological basis for concentrated iliac crest aspirate to enhance core decompression in the treatment of osteonecrosis

Core decompression is a surgical procedure that is capable of salvaging the patient's own natural joint, if the operation is performed in the early stages of osteonecrosis, in which the articular surface has not collapsed. The addition of concentrated cells, aspirated from the iliac crest, to the core tract has been shown to enhance the viability of the femoral head, although large, prospective, randomized, blinded multicentre studies are lacking. The rationale for adding these cells to the core decompression tract is to provide osteoprogenitor and vascular progenitor cells to the area of decompressed dead bone, in order to facilitate tissue regeneration and repair. It has become increasingly evident that vast discrepancies exist in different series in regard to the criteria for patient selection, the surgical technique of core decompression, the methods for harvesting, processing, and injecting the cells, and the methodology for determining success or failure in a specific patient cohort. This paper reviews the salient points relevant to the treatment of osteonecrosis by core decompression with addition of concentrated iliac crest aspirates and poses important questions regarding the future successful application of this technique.

Avascular Necrosis of the Femoral Head

About 250000 patients are operated on annually for hip arthroplasty in the USA alone. Of this number, about 10% the cause of their osteoarthritis is the avascular necrosis of the femoral head. But the causes of necrosis are multiple and many of them are still unknown. That is why small advances in etiopathogenesis, diagnosis and treatment of different causes are very important in order to reduce the number of affected patients. It may seem that small changes, studies focused on the details of different diseases do not bring great changes to science, but it is these small changes that end up adding great evolutions in our knowledge. In addition, the changes of recent years, are not focused on our specialty in technical or anatomical evolutions exclusively, but are often based on biological bases, which is the branch that evolves more within trauma and orthopedics. That is why open and constant minds are what help us move forward.

The Pathophysiological Sequence of Glucocorticoid-Induced Osteonecrosis of the Femoral Head in Male Mice

In search of the sequence of pathogenic events leading to glucocorticoid-induced osteonecrosis, we determined the molecular, biomechanical, cellular, and vascular changes in the femur of C57BL/6 mice receiving prednisolone for 14, 28, or 42 days. The femoral head, but not the distal femur, of mice treated for 14 days showed a decrease in the expression of the hypoxia-inducible factor (Hif)-1α and vascular endothelial growth factor (VEGF), the number of osteoblasts, and bone formation rate and strength and showed an increase in osteoclasts. These changes were accompanied by conversion of the normal dendritic vasculature to pools of edema as detected by magnetic resonance imaging, providing robust diagnostic evidence of early osteonecrosis. At that time point, there were no detectable changes in bone density, cortical or cancellous bone architecture, midshaft or distal cancellous bone, or osteocyte apoptosis. In mice treated for 28 days, femoral head cancellous density, cortical width, and trabecular thickness decreased, and by 42 days the femoral heads had full-depth cortical penetrations and cancellous tissue osteonecrosis. These results indicate that the femoral head is a particularly sensitive anatomical site to the adverse effects of glucocorticoid excess on bone and that decreases of Hif-1α and VEGF expression, bone vascularity, and strength precede the loss of bone mass and microarchitectural deterioration, thus rendering the femoral head vulnerable to collapse.

High incidence of aseptic hip necrosis in Hodgkin lymphoma patients treated with escalated BEACOPP receiving methylprednisolone

BACKGROUND

Escalated BEACOPP (eBEACOPP) is an effective but fairly toxic regimen for the treatment of Hodgkin lymphoma (HL). Avascular necrosis (AVN) of femoral head was previously reported to increase in patients treated with eBEACOPP, but so far, no systematic analysis of its frequency has been published.

AIMS

To analyse the frequency and identify possible risk factors for AVN development in patients treated with eBEACOPP.

METHODS

We identified 26 patients treated with eBEACOPP for newly diagnosed high-risk advanced-stage HL, 25 of whom were alive at the time of study. All patients were invited to participate in a cross-sectional study; 17 patients responded and were evaluated by magnetic resonance imaging and orthopaedic examination.

RESULTS

Six patients (35.3%) were diagnosed with AVN after receiving eBEACOPP treatment. AVN was not correlated with age, gender, number of received eBEACOPP cycles, irradiation therapy or cumulative dose of steroids administered. There were significantly more cases of AVN in patients receiving methylprednisolone than prednisone (P = 0.01).

CONCLUSION

The use of methylprednisolone was shown to be a risk factor for the development of AVN in patients treated with eBEACOPP and should not be the corticosteroid of choice in the treatment of patients with HL.

Avascular necrosis in children with cerebral palsy after reconstructive hip surgery

PURPOSE

Progressive hip displacement is one of the most common orthopaedic pathologies in children with cerebral palsy (CP). Reconstructive hip surgery has become the standard treatment of care. Reported avascular necrosis (AVN) rates for hip reconstructive surgery in these patients vary widely in the literature. The purpose of this study is to identify the frequency and associated risk factors of AVN for reconstructive hip procedures.

METHODS

A retrospective analysis was performed of 70 cases of reconstructive hip surgery in 47 children with CP, between 2009 and 2013. All 70 cases involved varus derotation osteotomy (VDRO), with 60% having combined VDRO and pelvic osteotomies (PO), and 21% requiring open reductions. Mean age at time of surgery was 8.82 years and 90% of patients were Gross Motor Function Classification System (GMFCS) 4 and 5. Radiographic dysplasia parameters were analysed at selected intervals, to a minimum of one year post-operatively. Severity of AVN was classified by Kruczynski's method. Bivar- iate statistical analysis was conducted using Chi-square test and Student's t-test.

RESULTS

There were 19 (27%) noted cases of AVN, all radio- graphically identifiable within the first post-operative year. The majority of AVN cases (63%) were mild to moderate in severity. Pre-operative migration percentage (MP) (p = 0.0009) and post-operative change in MP (p = 0.002) were the most significant predictors of AVN. Other risk factors were: GMFCS level (p = 0.031), post-operative change in NSA (p = 0.02) and concomitant adductor tenotomy (0.028).

CONCLUSION

AVN was observed in 27% of patients. Severity of displacement correlates directly with AVN risk and we suggest that hip reconstruction, specifically VDRO, be performed early in the 'hip at risk' group to avoid this complication.

Association of SREBP2 gene polymorphisms with the risk of osteonecrosis of the femoral head relates to gene expression and lipid metabolism disorders

Although lipid metabolism disorders have been recognized as a primary factor of osteonecrosis of the femoral head (ONFH), the molecular pathogenesis remains unclear. Sterol regulatory element‑binding protein 2 (SREBP2) specifically regulates cholesterol and fatty acid metabolism to maintain lipid homeostasis. To explore the roles of the SREBP2 gene in the development of ONFH, the authors analyzed the gene polymorphism and gene expression of three tag single nucleotide polymorphisms of the SREBP2 gene, the serum lipids levels, and their associations with ONFH development in 182 ONFH patients and 179 healthy controls. The results demonstrated that the stage IV proportions of ONFH patients carrying the rs2267439CT or CC genotype were significantly higher and lower than the stage III proportions of ONFH patients (P=0.039), respectively. The serum triglyceride, low‑density lipoprotein (LDL)‑c levels, and LDL‑C/high‑density lipoprotein (HDL)‑C ratio in the ONFH group were significantly increased compared to those in the control group (P=0.01, P=0.005, P=0.0001) while the HDL‑C level of ONFH group was remarkably lower than that of the control group (P=0.0001). Association analysis further revealed that the LDL‑c levels of the rs226744 GG and AG genotype carriers were statistically higher than that of the AA genotype carriers (P=0.039, P=0.05). These results demonstrated that the gene polymorphism of SREBP2 not only significantly associated with the clinical phenotypes of ONFH but also closely related to lipid metabolism disorder. The results indicated that SREBP2 gene polymorphism and function may play key roles in the development of ONFH.

A PET/MR Imaging Approach for the Integrated Assessment of Chemotherapy-induced Brain, Heart, and Bone Injuries in Pediatric Cancer Survivors: A Pilot Study

Purpose To develop a positron emission tomography (PET)/magnetic resonance (MR) imaging protocol for evaluation of the brain, heart, and joints of pediatric cancer survivors for chemotherapy-induced injuries in one session. Materials and Methods Three teams of experts in neuroimaging, cardiac imaging, and bone imaging were tasked to develop a 20-30-minute PET/MR imaging protocol for detection of chemotherapy-induced tissue injuries of the brain, heart, and bone. In an institutional review board-approved, HIPAA-compliant, prospective study from April to July 2016, 10 pediatric cancer survivors who completed chemotherapy underwent imaging of the brain, heart, and bone with a 3-T PET/MR imager. Cumulative chemotherapy doses and clinical symptoms were correlated with the severity of MR imaging abnormalities by using linear regression analyses. MR imaging measures of brain perfusion and metabolism were compared among eight patients who were treated with methotrexate and eight untreated age-matched control subjects by using Wilcoxon rank-sum tests. Results Combined brain, heart, and bone examinations were completed within 90 minutes. Eight of 10 cancer survivors had abnormal findings on brain, heart, and bone images, including six patients with and two patients without clinical symptoms. Cumulative chemotherapy doses correlated significantly with MR imaging measures of left ventricular ejection fraction and end-systolic volume, but not with the severity of brain or bone abnormalities. Methotrexate-treated cancer survivors had significantly lower cerebral blood flow and metabolic activity in key brain areas compared with control subjects. Conclusion The feasibility of a single examination for assessment of chemotherapy-induced injuries of the brain, heart, and joints was shown. Earlier detection of tissue injuries may enable initiation of timely interventions and help to preserve long-term health of pediatric cancer survivors. ^© RSNA, 2017 Online supplemental material is available for this article.

Analysis of Cell Therapies Used in Clinical Trials for the Treatment of Osteonecrosis of the Femoral Head: A Systematic Review of the Literature

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is associated with regional loss of cells within bone, often resulting in pain and mechanical collapse. Our purpose was to analyze the cell-therapies used in clinical trials for the treatment of ONFH with regard to (1) cell-sources, (2) collection techniques, (3) cell-processing, (4) qualitative and quantitative characterizations, and (5) delivery methods.

METHODS

A systematic review of the current literature on the use of cell therapies for the treatment of ONFH was performed. Studies with a level-of-evidence III or higher were evaluated. A total of 1483 articles were screened. Eleven studies met the criteria to be included in this review.

RESULTS

Ten studies used bone-marrow, and 1 study used blood as the cell-source. Nine studies used freshly isolated tissue-derived nucleated cells from bone-marrow, mixed bone marrow-derived nucleated cells, 1 study used mixed blood-derived nucleated cells, and 1 study used culture-expanded cells derived from bone marrow aspirate. Cell dose varied from 2-million to 3-billion cells. Qualitative cell characterization of injected cells using surface markers was done by 5 studies using CD34. Two studies assayed the cell-population using a colony-forming-unit assay.

CONCLUSION

There is a lack of standardization with respect to the quantitative and qualitative characterization of methods for cell-harvest, cell-processing, and cell-transplantation/delivery. Cell-therapy holds promise as a means of restoring local cell populations that are made deficient because of injury or disease. However, the orthopedic community and patients will benefit greatly by a greater investment in blinded, randomized, controlled trials and clinical effectiveness trials that embrace rigorous standards.

Association of gene variants of transcription factors PPARγ, RUNX2, Osterix genes and COL2A1, IGFBP3 genes with the development of osteonecrosis of the femoral head in Chinese population

The molecular pathogenesis of osteonecrosis of the femoral head (ONFH) has been remained obscure so that its prevalence has been increasing in recent decades. Different transcription factors play critical roles in maintaining the balance between osteogenesis and adipogenesis. However, it has been unclear that the genes variants of the transcription factors exert the effects on the imbalance between steogenesis and adipogenesis during the development of ONFH. Here, we selected the 11SNPs from steogenesis, adipogenesis-specific transcription factors RUNX2, Osterix, and PPARγ genes, chondrogenesis or adipogenesis key factors COL2A1, IGFBP3 genes and analysed the genotypes, alleles, haplotypes and their association with the risk and clinical phenotypes of ONFH through Mass ARRAY® platformin in 200 ONFH patients and 177controls. The patients with ONFH (132 males, 68 females; age: 53.46±11.48yr) were consecutively enrolled at the Department of Orthopedics, the Second Clinical College of Jilin University, from March 2014 to June 2015 and were diagnosed and classified into 10 cases of stage II (5.6%), 54 cases of stage III (30.2%) and 115 cases (64.2%) of stage IV and alcohol-induced (71 cases (39.7%)), idiopathic (64 cases (34.0%)), and steroid-induced osteonecrosis (47 cases (26.3%)) subgroup, respectively. Our results showed that all models of logistical regression analysis, the co-dominants, dominants, and recessives of PPARγrs2920502, significantly associated with the increased risk of ONFH (p=0.004, p=0.013, p=0.016), respectively. Both the minor homozygous CC genotype and the allele C of rs2920502 were evidently correlated with the enhanced risk of ONFH (p=0.005, p=0.0005),respectively. The recessives models of IGFBP3rs2132572 (G/A) as well as RUNX2 rs3763190(G/A) were statistically associated with the higher ONFH risk, p=0.030, p=0.029, respectively; the minor homozygous(AA) of IGFBP3rs2132572 (G/A) was also related to the increased risk of bilateral hips lesions, p=0.039. Moreover, the ages on set of major homozygous(GG) and heterozygous(GT) of COL2A1rs2070739(G/A) were significantly younger than that of the minor homozygous(AA) of the SNP(p=0.008) while the A-T-G-A haplotype of COL2A1 gene revealed significant association with the decreased the risk of bilateral hip lesions, p=0.01, OR:0.258. More important, the serum HDL-c level and the ratio of LDL-c/HDL-c in the ONFH group were significantly decreased and increased compared with those of the control group (p=0.02, p=0.0001), respectively. Particularly, the CC genotype of PPARγ rs2920502 was statistically correlated with the enhanced serum TG level, p=0.011.These results suggest that the variants of PPARγ, RUNX2, COL2A1, and IGFBP3 genes closely associated with the development of ONFH.

Bone marrow oedema predicts bone collapse in paediatric and adolescent leukaemia patients with corticosteroid-induced osteonecrosis

OBJECTIVES

Corticosteroid treatment of paediatric leukaemia patients can lead to osteonecrosis (ON). We determined whether bone marrow oedema (BME) is an early sign of progressive ON and eventual bone collapse.

METHODS

In a retrospective study, two radiologists reviewed MR imaging characteristics of 47 early stage epiphyseal ON in 15 paediatric and adolescent leukaemia patients. Associations between BME on initial imaging studies and subchondral fracture, disease progression and bone collapse were assessed by Cochran-Mantel-Haenszel tests. Differences in time to progression and bone collapse between lesions with and without oedema were assessed by log rank tests.

RESULTS

Forty-seven occurrences of ON were located in weight bearing joints, with 77% occurring in the femur. Seventeen lesions progressed to collapse, two lesions worsened without collapse, and 28 remained stable or improved. BME was significantly associated with subchondral fracture (p = 0.0014), disease progression (p = 0.0015), and bone collapse (p < 0.001), with a sensitivity and specificity of 94% and 77%, respectively, for bone collapse. Time to progression for ON with oedema was 2.7 years (95% CI: 1.7-3.4); while the majority of no-oedema ON were stable (p = 0.0011).

CONCLUSIONS

BME is an early sign of progressive ON and eventual bone collapse in paediatric and adolescent leukaemia patients.

KEY POINTS

• Bone marrow oedema in corticosteroid-induced osteonecrosis predicts progression to bone collapse. • Bone marrow oedema is associated with subchondral fractures in corticosteroid-induced osteonecrosis. • Bone marrow oedema can be used to stratify patients to joint-preserving interventions. • Absence of bone marrow oedema can justify a "wait and watch" approach.

Associations of TNF-α -238 A/G and IL-10 -1082 G/A Genetic Polymorphisms With the Risk of NONFH in the Chinese Population

The study aims to explore the roles of common polymorphisms of Tumor Necrosis Factor-α (TNF-α) (-238 A/G and -308 A/G) and IL-10 (-819 T/C and -1082 G/A) genes in the risk of non-traumatic osteonecrosis of the femoral head (NONFH). One hundred and forty-seven NONFH patients and 135 healthy individuals were selected as the case and control groups. qRT-PCR and Western blotting techniques detected mRNA as well as protein expressions of TNF-α and IL-10 of each genotype in both the case and control groups. The GA genotype and the A allele of TNF-α -238 A/G were higher in the case group than in the control group. Compared with the control group, AA, GA, and AG + AA genotypes as well as the A allele of IL-10-1082 G/A were all lower in the case group. In the case groups increased levels of TNF-α as well as decreased levels of IL-10 expression when compared with the control group. TNF-α expression of TNF-α-238 GA genotype was significantly higher than that in patients with GG genotype, while the IL-10 expression of GA and AA genotypes of IL-10-1082 was significantly lower than in that of patients with the GG genotype. TNF-α protein expression in the GA genotype was significantly higher than in the GG genotype. In relation to TNF-α -238, TNF-α protein expression of GA and AA genotypes had significantly reduced more so than the GG genotype in IL-10-1082. TNF-α-238 A/G and IL-10-1082 G/A may be involved as risk factors of NONFH. J. Cell. Biochem. 118: 4872-4880, 2017. © 2017 Wiley Periodicals, Inc.

Hemodynamic changes in osteonecrosis treatment of the femoral head with iliac bone flaps pedicled with the lateral femoral circumflex artery ascending branch: A 10-year report

BACKGROUND

Vascularized bone grafting was used in the treatment of osteonecrosis femoral head, which may directly influence the pathologic event of femoral head.

OBJECTIVE

This paper evaluates hemodynamic changes in osteonecrosis treatment of the femoral head (ONFH) with iliac bone flaps from the lateral femoral circumflex artery ascending branches via digital subtraction angiography.

METHODS

A total of 48 patients, (31 males and 17 females; 38 at stage II and 10 at stage III), were treated with iliac bone flaps pedicled with the ascending branch of the lateral femoral circumflex artery. DSA was performed on all 48 patients preoperatively and 6 months postoperatively, and 10 years postoperatively on 1 patient.

RESULTS

Six months after surgery, femoral head blood supplies were distinctly visualized in the selective DSA in 44 cases. 4 patients showed poor or failed vessel pedicle filling in the transplanted bone flaps. Total hip arthroplasty was performed on these 4 patients. DSA was conducted 10 years post-operation in 1 case; the subject showed normal blood supply of the femoral head.

CONCLUSIONS

The anatomical position of the ascending branch of the lateral femoral circumflex artery was constant. Digital subtraction angiography successfully examined hemodynamic changes in osteonecrosis treatment of the femoral head with vascularized bone flaps.

Evidence for the Use of Cell-Based Therapy for the Treatment of Osteonecrosis of the Femoral Head: A Systematic Review of the Literature

BACKGROUND

Cell-therapy has been promoted among the therapeutic arsenal that can aid in bone formation and remodeling, in early stages of osteonecrosis of the femoral head (ONFH). The purpose of this systematic review was to assess the evidence supporting the (1) clinical efficacy; (2) structural modifying effect, as evaluated radiographically; (3) revision rates; and (4) safety of cell-therapy for the treatment of ONFH.

METHODS

A systematic review was performed including studies with a level-of-evidence of III or higher. A total of 1483 articles were screened. Eleven studies met the criteria for inclusion in this review (level-of-evidence: 6 level-I, 1 level-II, and 4 level-III), including 683 cases of ONFH.

RESULTS

All 10 studies that reported patient-reported outcomes showed improved outcomes in the cell-therapy groups compared with the control group. Overall, 24.5% (93/380 hips) that received cell-therapy showed radiographic progression compared with 40% (98/245 hips) in the control group. Nine of 10 studies that reported failure rates showed a lower total hip arthroplasty conversion rate in the cell-therapy group 16% (62/380 hips) compared with the control group 21% (52/252 hips). There was a low complication rate (<3%) with no major adverse effects.

CONCLUSION

Cell-therapies for the treatment of ONFH have been reported to be safe and suggest improved clinical outcomes with lower disease progression rate. However, there was substantial heterogeneity in the included studies, and in the cell-based therapies used. Specific clinical indications and cell-therapy standardization are required because studies varied widely with respect to cell sourcing, cell characterization, adjuvant therapies, and assessment of outcomes.

The use of anticoagulants for prevention and treatment of osteonecrosis of the femoral head: A systematic review

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a progressive disease, which mainly affects young adults and often necessitates total hip arthroplasty (THA), so early interventions are critical to successfully protect hip joint from THA. In this review, our purpose was to determine the effects of anticoagulants for preventing and treating the primary and secondary ONFH, respectively, before the collapse stage or before the pathology of necrosis.

METHODS

We searched PubMed, Embase, Web of Science databases for relevant studies. Any observational or experimental studies that evaluated anticoagulants and ONFH were our goal of searching the electric databases.

RESULTS

Four studies including a total of 218 hips were identified in this review, 2 of them were prospective studies which performed by 1 group, 1 was a retrospective study, and the last was a prospective comparative study.

CONCLUSIONS

Our findings supported that the anticoagulants could be used for primary ONFH. However, anticoagulants cannot play a protective role on secondary ONFH. Moreover, there were no serious adverse effects reported in the studies after anticoagulants treatment. Nevertheless, our present study with some limitations such as the limited sample size only provided limited quality of evidence; confirmation from further systematic review or meta-analysis with large-scale, well-designed randomized control trials is required.

Region specific Raman spectroscopy analysis of the femoral head reveals that trabecular bone is unlikely to contribute to non-traumatic osteonecrosis

Non-traumatic osteonecrosis (ON) of the femoral head is a common disease affecting a young population as the peak age of diagnosis is in the 40 s. The natural history of non-traumatic ON leads to a collapse of the femoral head requiring prosthetic replacement in a 60% of cases. Although trabecular bone involvement in the collapse is suspected, the underlying modifications induced at a molecular level have not been explored in humans. Here, we examine changes in the molecular composition and structure of bone as evaluated by Raman spectroscopy in human end-stage ON. Comparing samples from femoral heads harvested from 11 patients and 11 cadaveric controls, we show that the mineral and organic chemical composition of trabecular bone in ON is not modified apart from age-related differences. We also show that the molecular composition in the necrotic part of the femoral head is not different from the composition of the remaining ‘healthy’ trabecular bone of the femoral head. These findings support that quality of trabecular bone is not modified during ON despite extensive bone marrow necrosis and osteocyte death observed even in the ‘healthy’ zones on histological examination.

Significant Associations of SOX9 Gene Polymorphism and Gene Expression with the Risk of Osteonecrosis of the Femoral Head in a Han Population in Northern China

Sex determining region Y-box 9 (SOX9) is a key transcription factor involved in cartilage formation during the embryonic development stage and cartilage growth and repair after birth. To explore the roles of polymorphism and expression of the SOX9 gene in the development of osteonecrosis of the femoral head (ONFH), we analyzed the polymorphism of rs12601701 [A/G] and rs1042667 [A/C] and the serum protein expression of the SOX9 gene in 182 patients with ONFH and 179 healthy control subjects. Results revealed that the A-A haplotype of SOX9 gene as well as the GG and AA genotypes of rs12601701 was significantly associated with increased ONFH risk (P = 0.038) and the risk of bilateral hip lesions of ONFH (P = 0.009), respectively. The C-A, A-A, and A-G haplotypes were also statistically associated with the decreased and increased risk of bilateral hip lesions of ONFH (P = 0.03, P = 0.048, and P = 0.013), respectively, while the A-A haplotype closely related to the clinical stages of ONFH (P = 0.041). More importantly, the serum SOX9 protein expression of the ONFH group was greatly decreased compared to control group (P = 0.0001). Our results first showed that the gene polymorphism and gene expression of SOX9 were significantly associated with the risk and clinical phenotypes of ONFH and also indicate that the SOX9 gene may play a key role in the development of ONFH.

Predicting the collapse of the femoral head due to osteonecrosis: From basic methods to application prospects

Collapse of the femoral head is the most significant pathogenic complication arising from osteonecrosis of the femoral head. It is related to the disruption of the maintenance of cartilage and bone, and results in an impaired function of the vascular component. A method for predicting the collapse of the femoral head can be treated as a type of clinical index. Efforts in recent years to predict the collapse of the femoral head due to osteonecrosis include multiple methods of radiographic analysis, stress distribution analysis, finite element analysis, and other innovative methods. Prediction methods for osteonecrosis of the femoral head complications originated in Western countries and have been further developed in Asia. Presently, an increasing number of surgeons have chosen to focus on surgical treatments instead of prediction methods to guide more conservative interventions, resulting in a growing reliance on the more prevalent and highly effective total hip arthroplasty, rather than on more conservative treatments. In this review, we performed a literature search of PubMed and Embase using search terms including "osteonecrosis of femoral head," "prediction," "collapse," "finite element," "radiographic images," and "stress analysis," exploring the basic prediction method and prospects for new applications.

Association of Genes Variants in RANKL/RANK/OPG Signaling Pathway with the Development of Osteonecrosis of the Femoral Head in Chinese Population

The RANKL/RANK/OPG pathway plays an important role in regulating bone remodeling and bone turnover. However, the association of the genes variants with the risk of ONFH has rarely been reported. Here, we analyzed the correlation of the 10 SNPs polymorphisms of RANKL, RANK, OPG, TRAF6, and NFATC1 genes with the risk and development of ONFH in 200 ONFH patients and 177 health controls of Chinese population with using Mass ARRAY® platform. The results showed that the recessive model of NFATC1rs9518 was significantly associated with increased ONFH risk (OR:8.223, P=0.048); the proportion of stage Ⅳ patients in the rs9518TC genotype carriers was statistically higher than that of stage Ⅲ patients (P=0.03); in the T-C haplotype carriers of Naftac1, the proportion of bilateral hips lesions was also significantly enhanced than that of unilateral hip lesions(P=0.05). In addition, the proportion of idiopathic ONFH in the TT genotype carriers of OPGrs2073617 was significantly higher than that of steroid or alcohol-induced ONFH, respectively, while in the TC genotype carriers of the SNP, the proportion of idiopathic ONFH remarkably decreased compared with that of Alcohol-induced ONFH, P=0.021. Our results were first found that NFATC1rs9518 closely associated with the risk and the development of ONFH, while OPGrs2073617 statistically correlated with the etiological classification of ONFH.

3D printing of Mg-substituted wollastonite reinforcing diopside porous bioceramics with enhanced mechanical and biological performances

Mechanical strength and its long-term stability of bioceramic scaffolds is still a problem to treat the osteonecrosis of the femoral head. Considering the long-term stability of diopside (DIO) ceramic but poor mechanical strength, we developed the DIO-based porous bioceramic composites via dilute magnesium substituted wollastonite reinforcing and three-dimensional (3D) printing. The experimental results showed that the secondary phase (i.e. 10% magnesium substituting calcium silicate; CSM10) could readily improve the sintering property of the bioceramic composites (DIO/CSM10-x, x = 0-30) with increasing the CSM10 content from 0% to 30%, and the presence of the CSM10 also improved the biomimetic apatite mineralization ability in the pore struts of the scaffolds. Furthermore, the flexible strength (12.5-30 MPa) and compressive strength (14-37 MPa) of the 3D printed porous bioceramics remarkably increased with increasing CSM10 content, and the compressive strength of DIO/CSM10-30 showed a limited decay (from 37 MPa to 29 MPa) in the Tris buffer solution for a long time stage (8 weeks). These findings suggest that the new CSM10-reinforced diopside porous constructs possess excellent mechanical properties and can potentially be used to the clinic, especially for the treatment of osteonecrosis of the femoral head work as a bioceramic rod.

Treatment of Pre-Collapse Stages of Osteonecrosis of the Femoral Head: a Systematic Review of Randomized Control Trials

BACKGROUND

Treatment for osteonecrosis of the femoral head (ONFH) remains controversial. Current reviews include low-level evidence studies evaluating the treatment of both pre-collapse and collapse stages of the disease.

QUESTIONS/PURPOSES

The purpose of the current study is to systematically review the literature evaluating core decompression (CD) with bone marrow mesenchymal cells (BMMCs), CD alone, and bisphosphonate treatment in pre-collapse ONFH by focusing just on randomized clinical trials (RCTs) reporting functional and radiologic outcomes. We aim to determine if the literature provides evidence supporting any single approach.

METHODS

Using PubMed and EMBASE databases, we reviewed the clinical evidence of treatments for pre-collapse ONFH following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Twelve RCTs met the inclusion criteria.

RESULTS

Results showed that CD with BMMCs has lower risk of femoral head collapse when compared to the CD alone excluding hips lost to follow-up (relative risk (RR) [95% CI]:0.25 [0.11, 0.60]; p = 0.002) and when assumed that hips lost to follow-up experienced collapse (RR [95% CI]: 0.11 [0.03, 0.47]; p = 0.003). Neither CD nor bisphosphonate treatments showed lower risk to femoral head collapse when compared to control treatments (p = 0.46 and 0.31, respectively).

CONCLUSION

Current literature shows that there is a lower risk of femoral head collapse in patients with ONFH treated with CD combined with BMMCs when compared to CD alone; however, there is no robust evidence to determine the effect on functional outcomes. More RCTs assessing new combination therapies and using standardized outcome measures are required.

Treatment of osteonecrosis of the femoral head with free vascularized fibular grafting: Results of 7.6-year follow-up

Objectives

The aim of this study was to determine long term follow up of the patients who had femoral head osteonecrosis and had been treated with free vascularized fibular grafting.

Patients and methods

We retrospectively reviewed 28 hips of 21 patients who had undergone free vascularized fibular grafting for the treatment of osteonecrosis of femoral head. There were 16 male and 5 female patients. The mean age of the patients at the time of surgery was 30.7 years (between 15 and 53 years). The mean follow-up time was 7.6 years (between 5 years and 9.2 years).

Results

During follow-up, one patient died because of leukemia, and one patient was lost. The remaining 26 hips of 19 patients were evaluated. According to the Ficat classification, at the time of surgery, 17 hips were in grade 2 and 9 hips were in grade 3. The post-operative Harris hip scores in grade II disease were excellent in 12 patients, good in 3 patients, and fair in 1 patient. In grade III disease, 1 patient was excellent, 5 patients were good, and 1 patient was fair. There was a significant increase in HHS scores (61 ± 9.7 vs 84 ± 17.8, p < 0.001).

Conclusion

Free vascularized fibular grafting yields extremely good results, particularly in pre-collapse stages of disease in young patients. The operation time does not mark increased if the surgical team is “familiar” with the procedure, and the residual fibular defect of the donor site does not impair the functions of daily living.

Level of Evidence

Level IV, Therapeutic study.

Skeletal involvement in Gaucher disease: An observational multicenter study of prognostic factors in the Argentine Gaucher disease patients

Patients with Gaucher type 1 (GD1) throughout Argentina were enrolled in the Argentine bone project to evaluate bone disease and its determinants. We focused on presence and predictors of bone lesions (BL) and their relationship to therapeutic goals (TG) with timing and dose of enzyme replacement therapy (ERT). A total of 124 patients on ERT were enrolled in a multi-center study. All six TG were achieved by 82% of patients: 70.1% for bone pain and 91.1% for bone crisis. However, despite the fact that bone TGs were achieved, residual bone disease was present in 108 patients on ERT (87%) at time 0. 16% of patients showed new irreversible BL (bone infarcts and avascular osteonecrosis) despite ERT, suggesting that they appeared during ERT or were not detected at the moment of diagnosis. We observed 5 prognostic factors that predicted a higher probability of being free of bone disease: optimal ERT compliance; early diagnosis; timely initiation of therapy; ERT initiation dose ≥45 UI/kg/EOW; and the absence of history of splenectomy. Skeletal involvement was classified into 4 major phenotypic groups according to BL: group 1 (12.9%) without BL; group 2 (28.2%) with reversible BL; group 3 (41.9%) with reversible BL and irreversible chronic BL; and group 4 (16.9%) with acute irreversible BL. Our study identifies prognostic factors for achieving best therapeutic outcomes, introduces new risk stratification for patients and suggests the need for a redefinition of bone TG. Am. J. Hematol. 91:E448-E453, 2016. © 2016 Wiley Periodicals, Inc.

Multiple drilling combined with simvastatin versus multiple drilling alone for the treatment of avascular osteonecrosis of the femoral head: 3-year follow-up study

Background

Multiple small drilling for core decompression is widely used to preserve the femoral head in patients with avascular necrosis of the femoral head (ANFH). Nevertheless, the clinical outcome remains controversial. Simvastatin has been demonstrated to promote bone formation and reduce bone adsorption. The purpose of this study was to determine whether simvastatin enhanced the effect of multiple decompressions in preventing progression of ANFH and to identify independent risk factors associated with poor results.

Methods

We retrospectively analyzed 58 hips in 36 patients, with a follow-up of 36 months. 20 patients (32 hips) underwent multiple drilling combined with simvastatin treatment (SIM group); 16 patients (26 hips) underwent multiple drilling alone (MD group). We defined clinical failure as a requirement for subsequent hip surgery or Harris Hip Score < 75. New occurrence of collapse or increased collapse > 2 mm on plain radiographs was defined as radiological failure.

Results

Successful clinical results were achieved in 27 of 32 hips (84 %) in the SIM group compared with 15 of 26 hips (58 %) in the MD group (OR = 0.2, CI (0.1, 0.6.), P = 0.032). Successful radiological results were achieved in 27 of 32 hips (84 %) in the SIM group and in 16 of 26 hips (61.5 %) in the MD group (P = 0.048). Body mass index, disease stage and location of lesion were independent prognostic factors for overall survival.

Conclusions

We believe that simvastatin could enhance the effects of multiple decompressions in preventing progression of ANFH and reducing the risk of femoral head collapse.

Effects of hypoxia on osteogenic differentiation of mesenchymal stromal cells used as a cell therapy for avascular necrosis of the femoral head

BACKGROUND AIMS

Avascular necrosis of the femoral head (AVN) occurs as common result of various conditions or develops as a primary entity, with a high freqency in young adults. Because of its tendency toward osteoarthritis requiring total hip arthroplasty, alternative treatments are being advocated, including cell therapy with mesenchymal stromal cells (MSCs). Because osteonecrotic bone is a severely hypoxic tissue, with a 1-3% oxygen tension, the survival and function of multipotent cells is questionable.

METHODS

In this study, the proliferative, immunophenotypic and osteogenic properties of bone marrow (BM)-derived MSCs from a clinical series of patients with AVN were evaluated under in vitro conditions mimicking the hypoxic milieu of AVN to verify the rationale for cell therapy. MSCs retrieved from the iliac crest (BM-MSC) were isolated, expanded and induced to osteogenic differentiation under a 2% pO2 atmosphere (hypoxia) in comparison with the standard 21% pO2 (normoxia) that is routinely used in cell culture assays.

RESULTS

Both proliferation and colony-forming ability were significantly enhanced in hypoxia-exposed BM-MSCs compared with BM-MSCs under normoxia. The expression of bone-related genes, including alkaline phosphatase, Type I collagen, and osteocalcin was significantly increased under hypoxia. Moreover, mineral deposition after osteogenic induction was not hampered, but in some cases even enhanced under low oxygen tension.

CONCLUSIONS

These findings support autologous cell therapy as an effective treatment to stimulate bone healing in the hypoxic microenvironment of AVN.

Core Decompression Augmented With Autologous Bone Marrow Aspiration Concentrate for Early Avascular Necrosis of the Femoral Head

Lack of necessary perfusion to the femoral head can lead to necrosis of the underlying bone (avascular necrosis) and result in femoral and acetabular surface changes in advanced stages. Numerous treatments have been reported in the literature, including nonoperative and surgical procedures. In addition to the standard core decompression, we describe the use of bone marrow aspirate to stimulate a healing response and bone grafting, allowing for immediate weight bearing postoperatively. The purpose of this article was to describe our method of core decompression augmented with bone marrow aspirate concentrate and bone grafting for the treatment of early avascular necrosis of the femoral head.

Bone regeneration strategies with bone marrow stromal cells in orthopaedic surgery

Bone is the most transplanted tissue human with 1 million procedures every year in Europe. Surgical interventions for bone repair are required for varied reasons such as trauma resulting non-union fractures, or diseases including osteoporosis or osteonecrosis. Autologous bone grafting is the gold standard in bone regeneration but it requires a second surgery with associated pain and complications, and is also limited by harvested bone quantity. Synthetic bone substitutes lack the osteoinductive properties to heal large bone defects. Cell therapies based on bone marrow or ex vivo expanded mesenchymal stromal stem cells (MSCs) in association with synthetic calcium phosphate (CaP) bone substitutes may be alternatives to autologous bone grafting. This manuscript reviews the different conventional biological and synthetic bone grafting procedures as well as the more recently introduced cell therapy approaches used in orthopaedic surgery for bone regeneration. Some clinical studies have demonstrated safety and efficacy of these approaches but regeneration of large bone defects remain challenging due to the absence of rapid and adequate vascularisation. Future directions in the field of bone regeneration are presented, such as testing alternative cell sources or in situ fabrication of vascularized bone grafts in patients.

Joint-preserving regenerative therapy for patients with early-stage osteonecrosis of the femoral head

Osteonecrosis of the femoral head is an intractable disease often occurring in patients aged 30–40 years that can cause femoral head collapse, pain, and gait disturbance. Background factors, including corticosteroid use, alcohol intake, and idiopathic causes, have been indicated. It is estimated that 70–80 % of osteonecrosis patients experience femoral head collapse, for which total hip arthroplasty is considered the most effective treatment, even in young patients. Thus, there is a crucial need for developing a minimally invasive regenerative therapy as a preventive surgery for femoral head collapse: this has been an important area of research in the past decades. Core decompression, the most popular minimally invasive surgery for osteonecrosis of the femoral head, has been used for a long time; however, it has been insufficient to prevent femoral head collapse. For further improvement in therapeutic efficacy, cell transplantation and the use of artificial bone and growth factors have been proposed in addition to core decompression. Since 2000, newer therapies such as autologous bone marrow cell transplantation and the embedding of metal implant rods have been developed in Europe and the USA; however, these approaches have yet to become a global standard. This practical review summarizes applied state-of-the-art regenerative therapy-based core decompression. We introduce the clinical application of recombinant human fibroblast growth factor (rhFGF)-2-impregnated gelatin hydrogel for patients with precollapse osteonecrosis of the femoral head. Radiography and computed tomography have confirmed bone regeneration inside the femoral heads around the region of rhFGF-2 gelatin hydrogel administration. With further development, the minimally invasive method, which can be expected to promote bone regeneration in necrotic areas, could become a useful early-stage treatment for osteonecrosis of the femoral head. Patients can resume their daily routine soon after surgery, and the procedure is inexpensive. As such, it is a promising regenerative therapy that can be actively employed in osteonecrosis of the femoral head before femoral head collapse.

Heparanase: a rainbow pharmacological target associated to multiple pathologies including rare diseases

In recent years, heparanase has attracted considerable attention as a promising target for innovative pharmacological applications. Heparanase is a multifaceted protein endowed with enzymatic activity, as an endo-β-D-glucuronidase, and nonenzymatic functions. It is responsible for the cleavage of heparan sulfate side chains of proteoglycans, resulting in structural alterations of the extracellular matrix. Heparanase appears to be involved in major human diseases, from the most studied tumors to chronic inflammation, diabetic nephropathy, bone osteolysis, thrombosis and atherosclerosis, in addition to more recent investigation in various rare diseases. The present review provides an overview on heparanase, its biological role, inhibitors and possible clinical applications, covering the latest findings in these areas.

Hip replacement in femoral head osteonecrosis: current concepts

Osteonecrosis of the femoral head is a destructive disease that usually affects young adults with high functional demands and can have devastating effects on hip joint. The treatment depends on extent and location of the necrosis lesion and on patient's factors, that suggest disease progression, collapse probability and also implants survival. Non-idiopathic osteonecrosis patients had the worst outcome. There is not a gold standard treatment and frequently it is necessary a multidisciplinary approach. Preservation procedures of the femoral head are the first choice and can be attempted in younger patients without head collapse. Replacement procedure remains the main treatment after failure of preserving procedures and in the late-stage ONFH, involving collapse of the femoral head and degenerative changes to the acetabulum. Resurfacing procedure still has good results but the patient selection is a critical factor. Total hip arthroplasties had historically poor results in patients with osteonecrosis. More recently, reports have shown excellent results, but implant longevity and following revisions are still outstanding problems.

Involvement of MicroRNA-210 Demethylation in Steroid-associated Osteonecrosis of the Femoral Head

Angiogenesis is an important event in steroid-associated osteonecrosis of the femoral head (SONFH). Here we performed miRNA microarray with SONFH tissues (ONs) and the adjacent normal tissues (NLs) to select the angiogenic miRNA. The results showed that miR-210 was differentially expressed in SONFH versus normal tissues. Unexpectedly, its specific transcription factor, hypoxia-inducible factor-1α, was shown of no significant changes in ONs compared with NLs. Further Bisulfite sequencing revealed that miR-210 is embedded in a CpG island and miR-210 gene has 2 CpG sites with lower methylation percentage in ONs compared with NLs. Additionally, ONs with lower miR-210 gene methylation exhibited higher miR-210 expression. Next, we found that the endothelial cells treated with demethylating agents could significantly increase the expression of miR-210, along with promoted cell viability and differentiation. Some angiogenic genes (VEGF, bFGF, TNF-α and PCNA) were up-regulated as well. In addition, the supernatant of the cells after demethylation treatment displayed an enhanced ability of recruiting new microvessels in vivo. Taken together, our study not only provides novel insights into the regulation of angiogenesis in this disease, but also reveals a therapeutic opportunity for treatment of SONFH patients with demethylating agents.