Management of avascular necrosis of femoral head at pre-collapse stage

MRI spectrum of avascular necrosis of femoral head in patients treated for COVID-19

BACKGROUND AND PURPOSE

This prospective observational study aimed to investigate the occurrence of avascular necrosis (AVN) of the femoral head in COVID-19 patients through MRI scans. The study examined the patterns of AVN in 110 individuals who had undergone conventional COVID-19 therapy and reported hip discomfort. This study highlights the importance of considering AVN as a potential complication of COVID-19 therapy, particularly in younger patients who experience hip discomfort.

METHODS

Individuals who had corticosteroid treatment for COVID-19 and experienced hip discomfort during 6 months between January 2022 and August 2022 were included in this study, and an MRI scan was done to observe changes in the hip joint.

RESULTS

The results were classified using the Ficat and Arlet classification system. The analysis revealed that AVN was not present in 91.81% of cases. However, Stage I AVN was detected in 4.54% of cases, Stage II AVN in 2.72% of cases, and Stage III AVN in 1.1% of cases. No cases of Stage IV AVN were observed.

CONCLUSIONS

The study concludes that AVN occurred in 6% of individuals who underwent conventional therapy for COVID-19 and experienced hip discomfort. In these settings (post COVID-19), normal MRI results were more typical, and mild AVN (Stage I) was a frequent finding in MRI scans that were positive.

Rehabilitation to Complement Unique Single-Stage Core Decompression and Total Hip Arthroplasty in Bilateral Avascular Necrosis: A Case Report

Avascular necrosis (AVN), a debilitating condition characterized by bone tissue death due to inadequate blood supply, can severely impact the hip joint, leading to pain, limited mobility, and joint dysfunction. The complex blood supply and mechanical stress on the hip make it particularly vulnerable to AVN. Early detection is challenging as AVN may remain asymptomatic initially, but as it progresses, it results in severe joint degeneration. This case report outlines the management of a 38-year-old male patient with a dermatomyositis history who presented with bilateral hip pain attributed to AVN. Radiological investigations diagnosed grade 2 AVN in the left hip and grade 3 AVN in the right hip. The patient underwent core decompression for the left hip to halt disease progression and total hip arthroplasty (THA) for the right hip to alleviate pain and restore function. A structured three-week rehabilitation program was tailored to each surgical procedure, with pre-and post-treatment assessments revealing notable improvements in pain relief, range of motion (ROM), and muscle strength. This case underscores the importance of early diagnosis, personalized surgical interventions, and comprehensive rehabilitation in managing AVN in dermatomyositis patients. Physiotherapy is vital pre- and post-operatively to enhance physical function, strength, and mobility. Rehabilitation also plays a crucial role in postoperative recovery, early mobilization, and functional restoration. The multifaceted approach employed in this case highlights the need for a comprehensive strategy when managing AVN in dermatomyositis patients, providing valuable insights for similar cases.

Autologous bone plug-sliding with core decompression and bone marrow aspirate concentrate application: a joint-preserving surgical technique for corticosteroid-induced osteonecrosis of femoral head

This study aimed to describe a surgical procedure for the management of corticosteroid-induced osteonecrosis of the femoral head (ONFH) and report its clinical results. The technique included harvesting a bone plug from the lateral femoral neck, core decompression, and bone marrow aspirate concentrate (BMAC) application; the procedure was completed by press-fit insertion of the autologous bone plug in the debrided area. Autologous bone plug-sliding with core decompression and bone marrow concentrate aspirate application provides good clinical outcomes in the management of ONFH. A retrospective review was performed using records of patients operated on between October 2019 and June 2021. Only patients with Ficat-Arlet stage-2 ONFH, who underwent the procedure described, were included. Twenty- nine hips (18 patients) were included and evaluated clinically and radiologically. Clinical evaluation included the Harris hip score (HHS) and Visual analogue scale (VAS) for pain, while radiological evaluation included direct radiographs. The average age was 39.8 years (± 11.7, range: 24-65 years). The average follow-up was 13.5 months (± 3.4, range: 8-19 months). There were improvements in the VAS pain and Harris hip scores in all patients. Average HHS increased from 61.90 to 87.45 (p < 0.001), while the average VAS pain score decreased from 7.14 to 3.27 (p < 0.001). No complications were encountered in any of the patients during the follow-up. None of the patients had femoral head collapse on the latest radiograph or required total hip replacement. The combination of the novel autologous bone plug-sliding method with conventional regenerative methods is a successful treatment choice for ONFH.

A Comprehensive Review of Treatment Strategies for Early Avascular Necrosis

Avascular necrosis (AVN), characterised by compromised blood supply leading to bone necrosis, poses a significant challenge in orthopaedic and rheumatologic practice. This review comprehensively examines early AVN treatment strategies, including aetiology and risk factors, clinical presentation, conservative and surgical approaches, emerging therapies, and rehabilitation. Key findings underscore the importance of early detection, personalised treatment plans, and a multidisciplinary approach involving orthopaedic specialists, rheumatologists, and physical therapists. The implications for clinical practice emphasise individualised care, staying abreast of emerging therapies, and patient education. Recommendations for future management strategies highlight the need for imaging technology advancements, regenerative therapies integration, and ongoing research into genetic and molecular pathways. As the field continues to evolve, translating research findings into clinical practice holds promise for improving outcomes and enhancing the overall quality of life for individuals affected by AVN.

Clinical and epidemiological features and therapeutic options of avascular necrosis in patients with sickle cell disease (SCD): a cross-sectional study

BACKGROUND

Avascular necrosis (AVN) is a debilitating complication in sickle cell disease (SCD) patients, and its management is usually challenging. This study aims to evaluate the clinical and epidemiological features and therapeutic options of AVN in sickle cell patients in Qatar.

PATIENTS AND METHODS

A cross-sectional study was conducted on a 49 SCD patients who were diagnosed with AVN and attended the hematology clinic at the National Center for Cancer care & research, Hamad Medical Corporation, Qatar between Jan-2011 to Jan2021.  Results: Forty-nine adult patients with SCD who were diagnosed with AVN were studied. The median age of the study population is 32 years, and the median age at the first AVN diagnosis was 26 years (range: 11-44 yr.). 37 (75.5%) patients suffered from multiple joints AVN while 12(24.5%) had single joint involvement. 31 (63.3%) patients had bilateral hip AVN and 18 (36.7%) had shoulder involvement. 30 patients (61%) were on Hydroxyurea treatment. Based on FICAT and Alert classification of AVN, 57 % of patients had stage III and above at first diagnosis. 20 (40.8%) were managed with a conservative approach, 11 (22.4%) received hyperbaric oxygen with good response, 6(12.2%) underwent hip core decompression and 12(24.5%) underwent hip replacement surgery.

CONCLUSION

In SCD patients, AVN occurred more during the 3rd and 4th decades of life. The majority of AVN represented with advanced stage and had multiple joint involvements. We recommend adopting a low threshold of joint imaging for early detection and prevention of further complications.

An Evaluation of Core Decompression and Cancellous Bone Grafting for Early-Stage Avascular Necrosis of the Femoral Head

Background Avascular necrosis (AVN) is characterized by bone death due to impaired blood supply leading to its collapse causing pain and suboptimal joint function. The blood supply of the femoral head is so tenuous that even a slight vascular injury can predispose to AVN. Hence, AVN is commonly seen in the femoral head. Core decompression can arrest or even reverse the process of AVN and can avoid femoral head collapse and its sequelae. A lateral trochanteric approach is used for core decompression. The necrotic bone is removed from the femoral head. The use of a non-vascularized bone graft is more attractive than a vascularized graft because it is significantly less technically challenging. The regenerative properties due to the presence of osteoblasts in the trabecular bone and the ability to procure a large amount of graft make the iliac crest the gold standard site of cancellous bone graft harvesting. Core decompression can be considered an effective treatment modality in early-stage AVN (up to stage 2B) of the femoral head. Methodology A prospective, interventional study was conducted in a tertiary care teaching hospital in southern Rajasthan, India. 20 Patients with AVN of the femoral head (up to grade 2B of Ficat and Arlet classification) who met the inclusion and exclusion criteria and presented to the orthopedic outpatient department of our institute were included in this study. Patients were treated with core decompression and cancellous bone grafting with a graft taken from the iliac crest. The Harris Hip Score (HHS) and Visual Analog Scale (VAS) score were used to assess the outcomes. Results In our study, the majority (50%) of the patients were in the 20-30-year age group, making it the most common age group with a male predominance (85%). In this study, the final result was calculated according to the HHS and VAS scores. The mean HHS was 69.45 preoperatively and 83.55 at six months postoperatively. Similarly, the mean VAS score was 6.3 preoperatively and 3.8 at six months postoperatively. Conclusions Core decompression with cancellous bone grafting is a promising procedure in stages 1 and 2 as it reduces the symptoms in the majority of cases and improves functional outcomes.

Case report: adipose-derived mesenchymal stem cells combined with core decompression in the treatment of early-stage avascular necrosis of the femoral head

INTRODUCTION

Core decompression is a well-known modality for treating the early stages of avascular necrosis of the femoral head (AVN), however, several methods have been suggested to augment this procedure and improve the outcomes.

CASE REPORT

A 52 male was diagnosed with a stage I AVN of the femoral head and treated with core decompression (CD) and injection of adipose-derived mesenchymal stem cells (AD-MSCs). The MRI showed full healing of the lesion after 3 months with significant clinical and functional improvement.

DISCUSSION

AD-MSCs could have the same capabilities as bone marrow-derived stem cells with many advantages, implantation of AD-MSCs in orthopedics and as an augmentation of core decompression has been tried before, but no clear guidelines nor methods of application are well established in the literature.

CONCLUSION

Implantation of AD-MSCs with Core decompression could be an effective modality to treat osteonecrosis of the femoral head in pre-collapse stages, however, we need bigger clinical studies to determine the actual effectiveness of this method.

Epidemiology and risk factors associated with avascular necrosis in patients with autoimmune diseases: a nationwide study

BACKGROUND/AIMS

Avascular necrosis (AVN) is a clinical condition characterized by the death of bone components due to interruption in the blood supply. This study aimed to investigate the epidemiology and determine the risk factors for AVN in patients with autoimmune diseases.

METHODS

We conducted a population-based retrospective cohort analysis using claims data from the Taiwan National Health Insurance Research Database. A total of 49,636 patients with autoimmune diseases between January 1, 2005 and December 31, 2013 were included. Cox regression analysis was used to identify associated risk factors for the development of AVN.

RESULTS

A total of 490/49,636 patients (1.0%) developed symptomatic AVN. The systemic lupus erythematosus patients had a higher risk of AVN compared to other autoimmune diseases. AVN was positively correlated with male sex (p < 0.001), alcoholism (p < 0.001), mean daily prednisolone dosage 7.51 to 30 mg (p < 0.001) and > 30 mg (p < 0.001), and total cumulative prednisolone dose 0 g to 5 g (p = 0.002). However, AVN was inversely correlated with cumulative duration of hydroxychloroquine exposure > 0.6 years (p < 0.001).

CONCLUSION

Male sex, systemic lupus erythematosus, alcoholism, mean daily corticosteroid > 7.5 mg and a total cumulative dose of corticosteroid 0 to 5 g were independently associated with the development of AVN in autoimmune patients. While hydroxychloroquine use > 0.6 years conferred significant protection against the development of AVN. Clinicians should regularly assess patients with risk factors to enable the early diagnosis of AVN.

Avascular Necrosis of Femoral Head-Overview and Current State of the Art

Avascular necrosis (AVN) of the femoral head is caused by disruption of the blood supply to the proximal femur. The alterations in the blood supply may occur following a traumatic event or result from a non-traumatic cause. Femoral neck fracture and hip dislocation and associated surgical procedures, corticosteroid therapy, and alcohol abuse frequently lead to AVN development. Type of fracture (displaced or undisplaced) and time between injury and surgery are the most critical factors in assessing the risk of developing AVN. Diagnosis of AVN can be established based on patients’ complaints, medical history, and radiographic findings. There is no consensus on the treatment of patients with AVN to date. Non-surgical methods are dedicated to patients in the early pre-collapse stages of the disease and consist of pharmacotherapy and physiotherapy. Surgery is recommended for patients with advanced disease.

Effectiveness of Calcium Sulfate and Hydroxyapatite Composite in Collapse Prevention in Osteonecrosis of Femoral Head

Introduction

Calcium-sulfate-hydroxyapatite bioceramics have been widely used as void fillers in bone. However, their effectiveness as void fillers in core decompression for osteonecrosis of the femoral head (ONFH) in preventing femoral head collapse prevention has limited evidence. The current study investigates the effectiveness of calcium-sulfate-hydroxyapatite bioceramics as a void filler in the core decompression procedure for ONFH.

Methods

We retrospectively reviewed the clinical and radiological records of ONFH patients that underwent core-decompression using either autologous iliac crest cancellous bone graft or calcium-sulfate-hydroxyapatite bioceramic paste as void fillers with at least one-year follow-up. The primary outcome of this study was the radiological progression of collapse in the last available standard anteroposterior (AP) radiographs of the hip. The collapse progression was compared between the two groups based on void fillers.

Results

This study included patient records with 44 hip joints that underwent core decompression. There were five female and 33 male patients. The mean age was 29.1±6.3 years. The mean follow-up duration was 21.4±3.4 months. No significant differences in collapse progression were observed between the two groups based on void fillers.

Conclusion

The use of calcium-sulfate-hydroxyapatite as a void filler in core decompress for ONFH is not superior to the autologous cancellous bone in terms of collapse prevention and mechanical support. Further modifications in the core decompression techniques and well-planned prospective studies would help establish sound recommendations.

Combination use of core decompression for osteonecrosis of the femoral head: A systematic review and meta-analysis using Forest and Funnel Plots

Objective

This study evaluated the efficacy and safety of CD combined with bone marrow stem cells in the treatment of femoral head necrosis by systematic review and meta-analysis. Methodology. PubMed, The Cochrane Library, Embase, CNKI, Google Scholar and MEDLINE, etc. databases were searched for clinical randomized controlled trials (RCTs) comparing core decompression combined with autologous bone marrow mesenchymal stem cells versus core decompression alone in the treatment of femoral head necrosis. The retrieval period is from the establishment of each database to May 20, 2021. After literature was extracted and literature quality was evaluated, meta-analysis was conducted by using RevMan5.3 software.

Results

A total of 420 osteonecrosis of the femoral head 452 patients' data were collected from all studies. Compared with the core decompression alone group, the CD combined with bone marrow stem cell showed marked reduction in the Visual analog scale (VAS), enhanced Harris hip score (HHS) at 12 months and 24 months, slowed down the progression of the disease, decreased the number of hips conversed to total hip arthroplasty (THA) in the future.

Conclusion

Core decompression therapy is a very effective and safe treatment process used for ONFH. Moreover, CD combined autologous bone marrow stem cell transplantation can improve the survival rate of the necrotic head, reduce hip pain and delay the disease progression, the rate of THA postoperatively.

Skeletal regeneration for segmental bone loss: Vascularised grafts, analogues and surrogates

Massive segmental bone defects (SBD) are mostly treated by removing the fibula and transplanting it complete with blood supply. While revolutionary 50 years ago, this remains the standard treatment. This review considers different strategies to repair SBD and emerging potential replacements for this highly invasive procedure. Prior to the technical breakthrough of microsurgery, researchers in the 1960s and 1970s had begun to make considerable progress in developing non autologous routes to repairing SBD. While the breaktthrough of vascularised bone transplantation solved the immediate problem of a lack of reliable repair strategies, much of their prior work is still relevant today. We challenge the assumption that mimicry is necessary or likely to be successful and instead point to the utility of quite crude (from a materials technology perspective), approaches. Together there are quite compelling indications that the body can regenerate entire bone segments with few or no exogenous factors. This is important, as there is a limit to how expensive a bone repair can be and still be widely available to all patients since cost restraints within healthcare systems are not likely to diminish in the near future. STATEMENT OF SIGNIFICANCE: This review is significant because it is a multidisciplinary view of several surgeons and scientists as to what is driving improvement in segmental bone defect repair, why many approaches to date have not succeeded and why some quite basic approaches can be as effective as they are. While there are many reviews of the literature of grafting and bone repair the relative lack of substantial improvement and slow rate of progress in clinical translation is often overlooked and we seek to challenge the reader to consider the issue more broadly.

Management of Posttraumatic Avascular Necrosis of the Proximal Humerus

The etiology of avascular necrosis (AVN) of the proximal humerus can be classified as idiopathic or posttraumatic, the latter being mainly due to proximal humerus fractures. Evidence suggests that posttraumatic AVN may require surgical intervention more often than idiopathic AVN of the proximal humerus. This article provides a comprehensive review of the management of posttraumatic AVN of the proximal humerus. Early stage AVN (stages 1 to 3) is commonly treated with nonoperative intervention or core decompression of the humeral head, whereas later stage disease (stages 4 and 5) may require hemiarthroplasty or total shoulder arthroplasty to restore function. [Orthopedics. 2021;44(6):367-375.].

Core decompression and bone marrow aspirate concentrate injection for Avascular Necrosis (AVN) of the femoral head: A scoping review

BACKGROUND

Various joint preserving treatments are available for use in Avascular Necrosis of the femoral head. Most of these are effective in the pre-collapse stage of the disease. This review aimed to evaluate the effectiveness of core decompression and Bone Marrow Aspirate Concentrate in various stages of AVN, in modifying the progression of the disease and the need for hip replacement.

MATERIAL AND METHODS

The Preferred Reporting Items for Systematic reviews and Meta-Analysis Extension for Scoping Reviews reporting guidelines were followed. The literature search was conducted from inception till 2^nd May 2021, on the PUBMED, SCOPUS, and Google Scholar search engines, using "bone marrow aspirate concentrate osteonecrosis femur" and "bmac osteonecrosis femur" as the keywords. In all these studies, Core Decompression with Bone marrow Aspirate concentrate was performed. The evaluation was done based on the progression of osteonecrosis, improvement in functional outcomes and the conversion to total hip arthroplasty.

RESULTS

We have analyzed 612 hips from11 studies, based on our inclusion and exclusion criteria. The mean age of the patients was 38.27 years. There was a predominance of males. The grade of AVN ranged from grade 1 to 4. The average follow-up period of the cases ranged from 2 to 12 years (average: 4.38 years). The functional scores were improved in the majority of cases. Radiographic progression occurred in 23.5% of hips, and the Total Hip Arthroplasty was performed in 14.9% of hips.

CONCLUSIONS

Core decompression with Bone Marrow Aspirate Concentrate in pre-collapse stages of the disease is beneficial in improving the functions scores and for reducing the radiological progression of the disease and need for total hip arthroplasty, in the majority of cases.

Concentric Circle Technique for Assessment of Femoral Head Deficiency in Osteonecrosis of Femoral Head

Introduction

There is a lack of standardized objective tools to assess collapse for osteonecrosis of the femoral head (ONFH) patients’ follow-up. We describe a quantitative technique of collapse assessment using a superimposed concentric circular ring matching the intact part of the femoral head in anteroposterior (AP) radiographs.

Methods

We retrospectively analyzed 30 normal femoral heads and 30 ONFH (15 pre-collapse,15 post-collapse) in anteroposterior hip radiographs. A best-fitting circle was superimposed on articular margins of the femoral head and the maximum width of the deficient zone of the femoral head (not matching the circle) was measured. The width (pW) was measured as percentage-width in proportion to the circle’s diameter. The findings were compared among normal and ONFH radiographs. Intraclass correlation coefficients were calculated for intraobserver and interobserver reliability of the measurements.

Results

The mean femoral head deficiencies predicted by pW were 0.2±0.5% for normal hip, 2.8±1.1% for pre-collapse, and 8.9±3.8% for post-collapse radiographs. We observed significant differences in the measurements of pW among the control group, pre-collapse and post-collapse groups. Interobserver and intraobserver reliabilities for the measurements were high.

Conclusion

The described concentric circle technique is a simple and reliable method for objective assessment of subtle alterations in the sphericity of the femoral head and can be helpful for the radiographic follow-up of ONFH patients.

Up-regulation of urinary exosomal hsa-microRNA-200b-3p and hsa-microRNA-206 in patients of steroid-induced osteonecrosis of femoral head

The aim of this study was to determine the value of microRNAs (miRNAs) in urinary exosomes in the diagnosis of steroid-induced osteonecrosis of femoral head (SONFH). RNA was extracted from urinary exosomes from 9 SONFH patients and 9 hip osteoarthritis (HOA) patients with age and gender matched and then miRNAs were analyzed by next generation sequencing. Intriguingly, 15 miRNAs including hsa-miR-200b-3p and hsa-miR-206 were significantly upregulated in exosomes from SONFH patients. Furthermore, qRT-PCR and area under curve (AUC) analysis of an independent cohort of 30 SONFH patients, 10 HOA patients and 10 healthy donors confirmed that hsa-miR-200b-3p and hsa-miR-206 were upregulated in SONFH samples which AUC values were 0.938 (95% CI: 0.828-1) and 0.926 (95% CI: 0.806-1) respectively. GO function, KEGG pathway, miRNAs-mRNAs network and protein-protein interaction (PPI) network were also constructed to analyze potentially pathological mechanisms. The enriched functions and pathways included Hippo, PI3K-Akt, TGF-β and Wnt signaling pathways. The top five hub genes (MAPK1, EP300, RHOA, PIK3CA, and CBL) were selected from PPI network, which consisted of 180 nodes and 518 edges. Collectively, our results showed that hsa-miR-200b-3p and hsa-miR-206 in urinary exosomes might serve as non-invasive biomarkers for SONFH.

Histopathological and immunohistochemical aspects of bone tissue in aseptic necrosis of the femoral head

Femoral head osteonecrosis, also known as avascular necrosis, is a disease with a multifactorial etiology, characterized by a profound change of bone architecture, which leads to the diminishing of bone resistance and femoral head collapse. The main causes that lead to femoral head necrosis are represented by the decrease of local blood perfusion and increase of intraosseous pressure, because of an excessive development of adipose tissue in the areolas of the trabecular bone tissue in the femoral head. The histopathological and immunohistochemical (IHC) study performed by us showed that most of bone trabeculae were damaged by necrotic-involutive processes, their sizes being reduced, both regarding their length and their diameter; generally, the spans were thin, fragmented, distanced among them, which led to the occurrence of some large areolar cavities, full of conjunctive tissue, rich in adipocytes. Some of the residual bone spans even presented microfractures. In the structure of the trabecular bone tissue, numerous cavities showed lack of content, which indicates the death of osteocytes inside, while the endosteum appeared very thin, with few osteoprogenitor, flattened, difficult to highlight cells. The IHC study showed a low reaction of the bone reparatory processes and a reduced multiplication capacity of bone cells involved in the remodeling and remake of the diseased bone tissue. Nevertheless, there were identified numerous young conjunctive cells (fibroblasts, myofibroblasts), positive to proliferating cell nuclear antigen (PCNA), cells that have a high capacity of multiplication, participating in the formation of a fibrous conjunctive tissue (sclerous) instead of the damaged bone trabeculae. The formation of fibrous conjunctive tissue causes the reduction of mechanical resistance of the femoral head and its collapse. The IHC study of the microvascularization in the femoral head damaged by aseptic osteonecrosis showed the presence of a very low vascular system, both in the residual bone trabeculae and in the sclerous conjunctive tissue. Of the inflammatory cells present in the spongy bone tissue of the femoral head affected by osteonecrosis, the most numerous ones were the macrophages. Both macrophages and T- and B-lymphocytes had a heterogenous distribution.

Deep Learning-Based End-to-End Diagnosis System for Avascular Necrosis of Femoral Head

As the first diagnostic imaging modality of avascular necrosis of the femoral head (AVNFH), accurately staging AVNFH from a plain radiograph is critical yet challenging for orthopedists. Thus, we propose a deep learning-based AVNFH diagnosis system (AVN-net). The proposed AVN-net reads plain radiographs of the pelvis, conducts diagnosis, and visualizes results automatically. Deep convolutional neural networks are trained to provide an end-to-end diagnosis solution, covering tasks of femoral head detection, exam-view identification, side classification, AVNFH diagnosis, and key clinical notes generation. AVN-net is able to obtain state-of-the-art testing AUC of 0.97 ( 95% CI: 0.97-0.98) in AVNFH detection and significantly greater F1 scores than less-to-moderately experienced orthopedists in all diagnostic tests ( p < 0.01). Furthermore, two real-world pilot studies were conducted for diagnosis support and education assistance, respectively, to assess the utility of AVN-net. The experimental results are promising. With the AVN-net diagnosis as a reference, the diagnostic accuracy and consistency of all orthopedists considerably improved while requiring only 1/4 of the time. Students self-studying the AVNFH diagnosis using AVN-net can learn better and faster than the control group. To the best of our knowledge, this study is the first research on the prospective use of a deep learning-based diagnosis system for AVNFH by conducting two pilot studies representing real-world application scenarios. We have demonstrated that the proposed AVN-net achieves expert-level AVNFH diagnosis performance, provides efficient support in clinical decision-making, and effectively passes clinical experience to students.

Study on the outcome of patients with aseptic femoral head necrosis treated with percutaneous multiple small-diameter drilling core decompression: a retrospective cohort study based on magnetic resonance imaging and equivalent sphere model analysis

Background

Aseptic necrosis of the femoral head (ANFH) has a high incidence in the community and causes substantial problems with health as well as economic and social stress. Core decompression is the most commonly used treatment for early ANFH. Although many studies have reported on the efficacy of femoral head core decompression surgery for ANFH, there are still some shortcomings in assessing the severity of femoral head necrosis, the location distribution, and changes in necrotic lesions before and after surgery. Magnetic resonance imaging (MRI) and equivalent sphere model analysis were used to further clarify the clinical efficacy of percutaneous multiple small-diameter drilling core decompression in patients with ANFH.

Methods

From July 2013 to November 2016, 24 patients (32 cases of the hip joint) with ANFH who underwent percutaneous multiple small-diameter drilling core decompression were selected, and a retrospective analysis was conducted. MRI as well as VAS, OHS-C, and HHS scores were used to evaluate joint function in all patients before and 6, 12, and 24 months after the operation.

Results

Twenty-four months after the operation, 10 hips were amputated. The survival rates of alcoholic femoral head necrosis (AFNH), idiopathic femoral head necrosis (IFHN), and steroid-induced femoral head necrosis (SIFHN) patients at 24 months were 100%, 85.7% (− 2 hips), and 0.0% (− 8 hips), respectively. The MRI and equivalent sphere analysis results revealed that the anterior superior medial quadrant was the area most prone to osteonecrosis, and the posterior superior medial quadrant was the area second most prone to necrosis. After the operation, the average percentage of the AFHN necrosis area in the total volume of the femoral head decreased from 14.5 to 10.3%, and the average percentage of the IFHN necrosis area decreased from 16.3 to 9.2%; however, the average percentage of the necrosis area for SIFHN increased from 30.4 to 33.1%.

Conclusion

Percutaneous multiple small-diameter drilling core decompression significantly reduced the lesion volume for AFHN and IFHN, but the effect on SIFHN was not good.

Serum exosomal hsa-miR-135b-5p serves as a potential diagnostic biomarker in steroid-induced osteonecrosis of femoral head

Accumulating studies have demonstrated serum exosomal microRNAs (miRNAs) represent novel biomarkers for various diseases. In this study, we aimed to explore the feasibility of using serum exosomal miRNAs as novel serological biomarkers for steroid-induced osteonecrosis of femoral head (SONFH). We identified the characters of exosomes which were obtained from fresh serum of 5 systemic lupus erythematosus (SLE) patients without SONFH, 5 SLE patients with SONFH (SLE-SONFH) and 5 healthy ones. Comprehensive exosomal miRNA sequencing was performed to profile the differentially expressed miRNAs in the three groups. We then validated the expression levels of selected miRNAs by qRT-PCR. Furthermore, KEGG pathway, GO annotation, protein-protein interaction (PPI) network, module analysis and miRNAs-mRNAs interaction network were built to analyze the potential targets and mechanism. Sequencing data conveyed that hsa-miR-135b-5p, hsa-miR-150-5p, hsa-miR-509-3-5p, hsa-miR-514a-3p and hsa-miR-708-5p were significantly differentially expressed in the three groups. The results of qRT-PCR for the first time confirmed that the expression of hsa-miR-135b-5p was strikingly up-regulated in SLE-SONFH group which were consistent with miRNA sequencing results. In addition, bioinformatics analysis indicated that the enriched functions and pathways of the most differentially expressed miRNAs including Wnt, MAPK as well as Hippo signaling pathway. The top five hub genes (FGF2, PTEN, HACE1, VAMP2, and CBL) were part of module of the PPI network, which consisted of 713 nodes and 2191 edges. In conclusion, this study provides a novel and fundamental serum exosomal miRNAs profile of SONFH and hsa-miR-135b-5p may be identified as a unique diagnostic biomarker for SONFH.

Osteonecrosis of the Hip: A Primer

In this report, we deliver a concise and up-to-date review of osteonecrosis, a pathologic, painful, and often disabling condition that is believed to result from the temporary or permanent disruption of blood supply to an affected area of bone. We will discuss the epidemiology (disease distribution), pathogenesis (mechanism of development), etiology (associated risk factors, causes, and disorders), clinical manifestations (reported symptoms and physical findings), diagnosis and classification, and treatment options for hip osteonecrosis.

Avascular necrosis post unstable slipped capital femoral epiphysis: a treatment algorithm with staged hinged hip distraction: mid-term results

BACKGROUND

Management of avascular necrosis (AVN) of the femoral head in slipped capital femoral epiphysis (SCFE) is difficult. We proposed to ascertain if staged hip distraction could prevent collapse and recover the femoral head.

METHODS

A retrospective review of the hip database retrieved 16 children with unstable SCFE and AVN. All underwent capital realignment by surgical dislocation followed by 2nd-stage hinged hip distraction. Patient demographics and radiographic parameters of deformity, AVN and arthritis were collected. The patients scored their hip function both before and after intervention and at follow-up using the modified Harris Hip Score and Nonarthritic Hip score.

RESULTS

7 boys and 9 girls formed the study group (n = 16). The average age at surgery was 12.7 years (9-16 years). 8 rights hips and 8 left hips were involved. The average follow-up was 45 months (33-66 months). Group A (n = 7) had hip distraction only if the follow-up radiographs showed AVN changes and collapse. Based on the observations in Group A, the protocol was changed for Group B. Group B (n = 9) underwent hip distraction at 6 weeks of capital realignment for avascularity of the femoral head. In Group A, all patients had further collapse and advanced arthritis at follow-up. In Group B all patients had hip joint space restored and good hip function without pain at follow-up.

CONCLUSIONS

Pre-emptive application of hip distractor for those children with proven lack of blood flow to the femoral head is a potential option to stall the progression of AVN and to help recover useful hip function.

Emergency Physician Reduction of Pediatric Hip Dislocation

Traumatic hip dislocation in children is relatively rare but presents a true emergency, as a delay in reduction can result in avascular necrosis of the femoral head and long-term morbidity. After sustaining a traumatic posterolateral hip dislocation, a seven-year-old boy presented to an outside facility where no attempt was made at reduction. The patient was transferred to our emergency department (ED) where he was promptly sedated and the dislocation was reduced in a timely manner. Emergency physicians have demonstrated high success rates with dislocation reduction. ED reduction should occur immediately to reduce the likelihood of long-term complications. While timely consultation with a pediatric orthopedist is recommended, that should not delay reduction. The reduction should ideally be performed before the patient leaves the department or is transferred to another facility.

Performance of a Deep Learning Algorithm in Detecting Osteonecrosis of the Femoral Head on Digital Radiography: A Comparison With Assessments by Radiologists

OBJECTIVE. The objective of our study was to compare the sensitivity of a deep learning (DL) algorithm with the assessments by radiologists in diagnosing osteonecrosis of the femoral head (ONFH) using digital radiography. MATERIALS AND METHODS. We performed a two-center, retrospective, noninferiority study of consecutive patients (≥ 16 years old) with a diagnosis of ONFH based on MR images. We investigated the following four datasets of unilaterally cropped hip anteroposterior radiographs: training (n = 1346), internal validation (n = 148), temporal external test (n = 148), and geographic external test (n = 250). Diagnostic performance was measured for a DL algorithm, a less experienced radiologist, and an experienced radiologist. Noninferiority analyses for sensitivity were performed for the DL algorithm and both radiologists. Subgroup analysis for precollapse and postcollapse ONFH was done. RESULTS. Overall, 1892 hips (1037 diseased and 855 normal) were included. Sensitivity and specificity for the temporal external test set were 84.8% and 91.3% for the DL algorithm, 77.6% and 100.0% for the less experienced radiologist, and 82.4% and 100.0% for the experienced radiologist. Sensitivity and specificity for the geographic external test set were 75.2% and 97.2% for the DL algorithm, 77.6% and 75.0% for the less experienced radiologist, and 78.0% and 86.1% for the experienced radiologist. The sensitivity of the DL algorithm was noninferior to that of the assessments by both radiologists. The DL algorithm was more sensitive for precollapse ONFH than the assessment by the less experienced radiologist in the temporal external test set (75.9% vs 57.4%; 95% CI of the difference, 4.5-32.8%). CONCLUSION. The sensitivity of the DL algorithm for diagnosing ONFH using digital radiography was noninferior to that of both less experienced and experienced radiologist assessments.

Minimally invasive treatment of femoral head avascular necrosis in a beta thalassemia carrier. A case-report

Avascular necrosis (AVNFH) of the femoral head is a relatively rare condition linked with numerous causes. If not treated promptly then arthritis may be inevitable, making hip replacement the only treatment option. In this case report we present a young AVNFH patient with history of heterozygous beta thalassemia. To our knowledge this is the second case where a thalassemia carrier presents AVNFH. Due to his age and pre-collapse stage, we elected to use a minimally invasive, femoral head sparing technique. Therefore, the patient underwent arthroscopy and fluoroscopy assisted core decompression followed by autograft and demineralized bone matrix application. Recovery was uneventful and a year after surgery femoral collapse did not progress. Moreover, the patient was pain free and capable of participating in sport activities. Even though it is difficult to describe a pathway linking heterozygous beta thalassemia with AVNFH, a possible relation between them cannot be discarded.

[Effect and mechanisms of vitamin E on early steroid-induced avascular necrosis of femoral head in rats]

Objective

To investigate the possibility of mitochondria-dependent apoptosis as a mechanism of early steroid-induced avascular necrosis of femoral head (SANFH) in rats and vitamin E as a possible prevention strategy.

Methods

Seventy-two male Sprague Dawley rats were randomly divided into control group, model group, and intervention group, with 24 rats in each group. The rats in control group were not treated as normal control. The rats in model group and intervention group were established early SANFH models by lipopolysaccharide combined with methylprednisolone injection. At the same time, the rats in intervention group were injected with vitamin E (40 mg/kg) every day for 7 days. At 2, 4, and 8 weeks after the final injection, the bilateral femoral heads were harvested and observed by HE staining, TUNEL assay, immunohistochemical staining, and Western blot. The rate of empty lacunae, apoptotic index, and the expressions of Caspase-9, Caspase-3, and cytochrome-c (Cyt-c) proteins were calculated.

Results

According to histological staining, there were significant differences in the rate of empty lacunae between intervention group and control group at 8 weeks ( P<0.05) and between intervention group and model group at 4 and 8 weeks ( P<0.05). The apoptotic index of intervention group was significantly lower than that of model group at each time point ( P<0.05). And there was significant difference between the intervention group and the control group at 8 weeks ( P<0.05). According to immunohistochemistry staining and Western blot, the expressions of Cyt-c, Caspase-9, and Caspase-3 all significantly decreased in intervention group than those in model group at each time point ( P<0.05); and the differences were significant between intervention group and control group at 8 weeks ( P<0.05).

Conclusion

Vitamin E can delay the progression of early SANFH by reducing mitochondrial dependent osteocyte apoptosis.

Effects of Zoledronic Acid and Vitamin E on Surgical- Induced Osteonecrosis of the Femoral Head in Rabbit

BACKGROUND

Femoral head osteonecrosis is a progressive disease with disabling outcomes in hip joint if not treated. This study was designed to compare the effects of zoledronic acid plus vitamin E versus zoledronic acid alone in surgical induced femoral head osteonecrosis in rabbits.

METHODS

26 Japanese white adult normal male rabbits at 28-32 weeks old were undertaken surgical femoral dislocation to devastate the femoral neck vessels; the femoral neck vessels were ligated and the hip was relocated. Next, the first 10 rabbits received zoledronic acid injections at 1^st and the 4^th weeks; the second group (10 rabbits) received zoledronic acid injections at 1^st and the 4^th week along with daily oral vitamin E for 12 weeks; and the third group was considered as non-treated control group. Radiographic and postmortem pathological assessments including the Ficat classification, epiphyseal quotient (EQ), new bone formation, and residual necrotic bone (RNB) were performed and compared after week 12.

RESULTS

A significant difference was found between the combination therapy group and the control group in Ficat classification at 12^th weeks (P=0.048), but, the difference between monotherapy and combination therapy groups at 12^th weeks was nonsignificant (P=0.37). Also, both treated groups had significant difference with the control group for RNB (P=0.015). There were no significant differences between the three groups for Ficat classification at the 6^th week (P=0.65); EQ at 6^th (P=0.59) and 12^th week (P=0.64); and NBF (P=0.55).

CONCLUSION

Although zoledronic acid therapy along with vitamin E could improve some radiologic and pathological indices related to femoral head osteonecrosis, vitamin E showed a relative impact.

LEVEL OF EVIDENCE

I.

Plasminogen Activator Inhibitor-1 4G/5G Polymorphism Contributes to Osteonecrosis of the Femoral Head Susceptibility: Evidence from a Systematic Review and Meta-analysis

BACKGROUND

The Plasminogen Activator Inhibitor-1 gene 4G/5G (PAI-1 4G/5G) polymorphism has been suggested to be associated with osteonecrosis of the femoral head (ONFH) susceptibility; however, the results are conflicting and inconclusive. We have carried out a comprehensive meta-analysis to derive a more precise estimation of the association.

METHODS

A comprehensive search in PubMed, EMBASE, Google Scholar, and ISI Web of Knowledge databases was conducted to identify all eligible case-control publications investigating the association between PAI-1 4G/5G polymorphism and ONFH risk. Odds ratios (OR) and corresponding 95% confidence intervals (CI) were used to assess the association.

RESULTS

A total of six studies with 456 cases and 1,019 controls were included in this review. Three studies were from Caucasian descendants and the three others were from East Asian descendants. Overall analysis suggests a significant association between PAI-1 4G/5G polymorphism and ONFH risk under the allele model (4G vs. 5G: OR =1.540, 95% CI =1.055-2.248, P=0.025) and the recessive model (4G4G vs. 4G5G+5G5G: OR=1.931, 95% CI: 1.162-3.207, P=0.011). When stratified by ethnicity, we have found a significant association between PAI-1 4G/5G polymorphism and ONFH risk among the Caucasian (4G5G vs. 5G5G: OR=1.806, 95% CI: 1.064-3.067, P=0.029) and East Asians (4G4G vs. 5G5G: OR=1.619, 95% CI: 1.025-2.556, P=0.039 and 4G4G vs. 4G5G+5G5G: OR=1.665, 95% CI: 1.207-2.297, P=0.002).

CONCLUSION

The present meta-analysis suggested that PAI-1 4G/5G (rs1799889) polymorphism is a potential risk factor for development of ONFH. However, large-scale and well-designed case-control studies in different ethnicities are required to validate these results.

Clinical and Radiological Outcomes of Extracorporeal Shock Wave Therapy in Early-Stage Femoral Head Osteonecrosis

Objective

Femoral head osteonecrosis is a progressive clinical condition with significant morbidity and long-term disability. Several treatment modalities including both surgical and nonsurgical options have been used with variable levels of success. High-energy extracorporeal shock wave therapy is a nonoperative treatment option that has been described for early-stage disease. We aimed to assess the functional and radiological outcomes of extracorporeal shockwave therapy (ESWT) in the treatment of osteonecrosis of the femoral head (ONFH).

Methods

Thirty-three hips of 21 patients were included in this study. Adult patients with ONFH of any etiology and in the precollapse stage were included. Clinical (visual analogue scale [VAS] and Harris hip score [HHS]) and radiological (plain radiographs and magnetic resonance imaging [MRI]) evaluations were performed before and after intervention. We used 3000–4500 pulses in a single session performed under general anesthesia.

Results

At an average of 8 months after ESWT, pain scores and HHS were significantly improved compared with the preintervention scores (p<0.001). The overall clinical outcomes were improved in 21 hips (63.3%), unchanged in 5 hips (15.15%), and worsened in 7 hips (21.2%). A trend toward a decrease in the size of the ONFH was observed although not of clinical significance (p=0.235). MRI revealed significant resolution of bone marrow edema (p<0.003). Regression was observed in 9 lesions (42.9%) and progression in 1 lesion (4.7%); no change was observed in the remaining 23 lesions (52.4%).

Conclusion

ESWT is a viable noninvasive treatment option for early-stage ONFH. It significantly improves clinical outcomes and may halt or delay the radiographic progression of the disease in the precollapse stage.

Differentially Expressed MicroRNAs in Conservatively Treated Nontraumatic Osteonecrosis Compared with Healthy Controls

Deregulation of microRNAs (miRNAs) contributes to nontraumatic osteonecrosis of the femoral head (ONFH-N), but the differentially expressed circulating miRNAs in patients with ONFH-N receiving nonsurgical therapy are unknown. This study aimed to determine the miRNAs expression profile of patients with ONFH-N receiving conservative treatments. This was a case-control prospective study of 43 patients with ONFH-N and 43 participants without ONFH-N, enrolled from 10/2014 to 10/2016 at the Department of Orthopedics of the Linyi People's Hospital (China). The two groups were matched for age, gender, and living area. Microarray analysis and quantitative RT-PCR were used to examine the differentially expressed miRNAs. Bioinformatics was used to predict miRNA target genes and signaling pathways. Microarray and quantitative RT-PCR revealed that nine miRNAs were downregulated and five miRNAs were upregulated in ONFH-N (n = 3) compared with controls (n = 3). Bioinformatics showed that calcium-mediated signaling pathway, regulation of calcium ion transmembrane transporter activity, cytoskeletal protein binding, and caveolae macromolecular signaling complex were probably regulated by the identified differentially expressed miRNAs. In the remaining 80 subjects (n = 40/group), miR-335-5p was downregulated (P = 0.01) and miR-100-5p was upregulated (P = 0.02) in ONFH-N compared with controls. In conclusion, some miRNAs are differentially expressed in conservatively treated ONFH-N compared with controls. Those miRNAs could contribute to the pathogenesis of ONFH-N.

Clinical reports of surgical dislocation of the hip with sequestrum clearance and impacting bone graft for grade IIIA-IIIB aseptic necrosis of femoral head (ANFH) patients

Objective

To analyze the treatment effect of surgical dislocation of the hip with sequestrum clearance and impacting bone graft in grade IIIA-IIIB aseptic necrosis of femoral head (ANFH) patients.

Methods

From June 2012 to December 2014, 6 patients (total 8 hips) with grade IIIA-IIIB ANFH were retrospectively followed. All the patients were operated with surgical dislocation of the hip with sequestrum clearance and impacting bone graft. Collapse of the femoral head, healing of the osteotomy, along with Harris hip scores were observed after surgeries.

Results

All the patients were followed up, the osteotomies were all healed. Only 1 of the 8 hips (12.5%) was collapsed by the last follow-up. Harris hip scores were improved from 54.52 ± 8.16 to 80.53 ± 7.62 (P <0.001). The excellent rate was 87.5%.

Conclusion

For grade IIIA-IIIB ANFH patients, surgical dislocation with sequestrum clearance and impacting bone graft could possibly achieve satisfactory clinical benefit, particularly for the young patients.

Differential expression of miR-195-5p in collapse of steroid-induced osteonecrosis of the femoral head

Background

Femoral head collapse is a key reference point for determining a treatment regimen of femoral head osteonecrosis. However, there are no effective preventive measures and the efficacy of hip-preserving surgery is unsatisfactory due to the unclear mechanism of collapse. This study aimed to identify and validate miRNAs differentially expressed in collapse and non-collapse areas of the osteonecrotic femoral head, and to predict the target genes and pathways of these miRNAs.

Results

Nine samples passed the quality control test. A total of 2085 differentially expressed miRNAs were detected, among which 433 miRNAs showed differential expression in the T1 group compared to the W1 group; 344 miRNAs showed differential expression in the T2 group compared to the W2 group; 107 miRNAs showed differential expression in the T3 group compared to the W3 group. After combining data from all three patients, 10 miRNAs showed differential expression in the collapse area (T1+T2+T3) compared to the non-collapse area (W1+W2+W3). Compared to the normal area, has-miR-195-5p showed the most significant downregulation. Expression results from RT-PCR revealed that the expression of hsa-miR-195-5p in the collapse area (T1+T2+T3) was significantly lower than that in the non-collapse area (W1+W2+W3) and normal area (Z1+Z2+Z3). 157 genes were perdicted as the target gene of hsa-miR-195-5p.

Materials and Methods

Femoral heads of three patients (2 males and 1 female) treated by total hip arthroplasty surgery for steroid-induced femoral head osteonecrosis were selected based on inclusion and exclusion criteria. Bone tissue samples were obtained from the collapse area (T), non-collapse area (W), and normal area (Z) according to the anatomical structure of osteonecrotic femoral heads. Total RNA was extracted from the samples and the microarray chip was scanned. miRNAs showing differential expressions of more than 1.5-fold were selected and was validated by RT-PCR. TargetScan, mirBase and miRanda bioinformatics software was used to predict target genes and identify possible pathways involving these genes.

Conclusions

miR-195-5p showed the most significant difference in the collapse area of osteonecrotic femoral heads, suggesting that collapse may be related to the downregulation of miR-195-5p.

THA conversion rate comparing decompression alone, with autologous bone graft or stem cells in osteonecrosis

INTRODUCTION

Core decompression (CD) with or without the addition of autologous bone graft (CDBG) is currently the most widely accepted treatment for hip osteonecrosis in stages of pre-collapse. The use of bone marrow mesenchymal stem cells (CDSC) is emerging as a promising biological alternative. We sought to determine the total hip arthroplasty (THA) conversion rate for patients treated with CD, CDBG or CDSC.

MATERIAL AND METHODS

Between 1996 and 2012, 97 cases were evaluated in 72 patients: 47 CD cases, 34 CDGB cases and 16 CDSC cases. The mean age was 39 (20-63) years, 25 bilateral, 19 female and 53 male, 14 Ficat 1 and 83 Ficat 2. Bilateral cases with asymmetric stage and equal treatment were excluded.

RESULTS

Conversion rate to THA was 44% for the CD group (21/47) at an average of 77 (24-324) months; 50% for the CDBG group (17/34) at an average of 34 (24-240) months and 50% for the CDSC group (8/16) at an average of 48 (24-72) months (p = 0.619). Log Rank test for survivorship analysis was not significant (p = 0.2011). Immunodeficiency or corticosteroid treatment history was associated with 16/47 of the CD group, 7/34 in the CDBG group and 1/16 in the CDSC group. Trauma was associated with 2/47 of the CD group, 5/34 of the CDBG group and none of the CDSC group. Hazard ratio considering risk factors was not significant (p = 0.252).

CONCLUSIONS

In these series of cases including patients with pre-collapse osteonecrosis, we observed non-significant results regarding rate of conversion to THA with CD, CDBG or CDSC at an average of 5.5 years.

11β-hydroxysteroid dehydrogenases as targets in the treatment of steroid-associated femoral head necrosis using antler extract

The aim of the present study was to investigate the therapeutic effect of deer antler extract on avascular necrosis of the femoral head (ANFH) induced by steroids, and to confirm that 11β-hydroxysteroid dehydrogenases (11β-HSD) are one of the targets of treatment with antler extract. A total of 30 rabbits were randomly divided into 5 groups (n=6): A control, ANFH, ANFH + antler (250 mg/kg), ANFH + antler (500 mg/kg) and ANFH + antler (1,000 mg/kg) group. Rabbits in the experimental groups were injected with methylprednisolone and horse serum to establish a steroid-induced ANFH (SANFH) model. Rabbits in the ANFH + antler (250 mg/kg), ANFH + antler (500 mg/kg) and ANFH + antler (1,000 mg/kg) groups were treated with intraperitoneal injection of 250, 500 or 1,000 mg/kg antler extract/day, respectively, for 60 days. Serum samples were then extracted to determine total cholesterol (CT) and triglyceride levels, treat osteoblasts, measure 11β-HSD (11β-HSD1) and 11β-HSD2 and alkaline phosphatase (ALP) levels and cellular apoptosis, and determine the proportion of osteoblasts in each phase of the cell cycle. Serum CT and triglyceride levels in SANFH rabbits significantly decreased as the concentration of antler increased (P<0.05). 11β-HSD1 levels in the femoral heads of SANFH rabbits and osteoblasts following treatment with antler-containing serum decreased as the concentration of antler used increased, whereas levels of 11β-HSD1 increased significantly (P<0.05). The proliferation of osteoblasts and ALP levels in osteoblasts increased as the antler concentration increased, whereas the number of osteoblasts in the G0/G1 phase decreased significantly (P<0.05). The current study demonstrated that treatment with antler extract has a therapeutic effect on ANFH induced by steroids in rabbits and may regulate the expression of 11β-HSD in femoral heads and osteoblasts, as well as promoting the proliferation of osteoblasts.

Femoral head necrosis: A finite element analysis of common and novel surgical techniques

BACKGROUND

Femoral head necrosis is a common cause of secondary osteoarthritis. At the early stages, treatment strategies are normally based on core decompression techniques, where the number, location and diameter of the drilling holes varies depending on the selected approach. The purpose of this study was to investigate the risk of femoral head, neck and subtrochanteric fracture following six different core decompression techniques.

MATERIALS

Five common and a newly proposed techniques were analyzed in respect to their biomechanical consequences using finite element analysis. The geometry of a femur was reconstructed from computed-tomography images. Thereafter, the drilling configurations were simulated. The strains in the intact and drilled femurs were determined under physiological, patient-specific, muscle and joint contact forces.

FINDINGS

The following results were observed: i) - an increase in collapse and fracture risk of the femur head by disease progression ii) - for a single hole approach at the subtrochanteric region, the fracture risk increases with the diameter iii) - the highest fracture risks occur for an 8mm single hole drilling at the subtrochanteric region and approaches with multiple drilling at various entry points iv) - the proposed novel approach resulted in the most physiological strains (closer to the experienced by the healthy bone).

INTERPRETATION

Our results suggest that all common core decompression methods have a significant impact on the biomechanical competence of the proximal femur and impact its mechanical potential. Fracture risk increases with drilling diameter and multiple drilling with smaller diameter. We recommend the anterior approach due to its reduced soft tissue trauma and its biomechanical performance.

Avascular Necrosis of Femoral Head: A Metabolomic, Biophysical, Biochemical, Electron Microscopic and Histopathological Characterization

Avascular necrosis of the femur head (AVNFH) is a debilitating disease caused due to the use of alcohol, steroids, following trauma or unclear (idiopathic) etiology, affecting mostly the middle aged population. Clinically AVNFH is associated with impaired blood supply to the femoral head resulting in bone necrosis and collapse. Although Homocysteine (HC) has been implicated in AVNFH, levels of homocysteine and its associated pathway metabolites have not been characterized. We demonstrate elevated levels of homocysteine and concomitantly reduced levels of vitamins B6 and B12, in plasma of AVNFH patients. AVNFH patients also had elevated blood levels of sodium and creatinine, and reduced levels of random glucose and haemoglobin. Biophysical and ultrastructural analysis of AVNFH bone revealed increased remodelling and reduced bone mineral density portrayed by increased carbonate to phosphate ratio and decreased Phosphate to amide ratio together with disrupted trabeculae, loss of osteocytes, presence of calcified marrow, and elevated expression of osteocalcin in the osteoblasts localized in necrotic regions. Taken together, our studies for the first time characterize the metabolomic, pathophysiological and morphometric changes associated with AVNFH providing insights for development of new markers and therapeutic strategies for this debilitating disorder.

Hyperbaric oxygen therapy modulates serum OPG/RANKL in femoral head necrosis patients

Hyperbaric oxygen therapy (HBOT) has beneficial effects on avascular necrosis of femoral head (ANFH), but its mechanism of action is still unclear. We investigated if HBOT upregulates serum osteoprotegerin (OPG) and/or inhibits osteoclast activation. 23 patients with unilateral ANFH at stage I, II and III consented to the study: the patients received standard HBOT. Serum OPG levels were obtained at the beginning of HBOT (T0), after 15 sessions (T1), 30 sessions (T2), after a 30-day break (T3), and after 60 sessions (T4). Magnetic resonance imaging (MRI) was obtained at T0 and about one year from the end of HBO treatments. Lesion size was compared between pre- and post-HBOT. 19 patients completed the study. HBOT reduced pain symptoms in all patients. HBOT significantly reduced lesion size in all stage I and II patients and in 2 of 11 stage III patients. HBOT increased serum OPG levels but receptor activator of nuclear factor kappa-B ligand (RANKL) levels did not change.

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.

The Efficacy of Bisphosphonates with Core Decompression and Mesenchymal Stem Cells Compared with Bisphosphonates Alone in the Treatment of Osteonecrosis of the Hip: a Retrospective Study

INTRODUCTION

Osteonecrosis of the femoral head (ONFH) is a devastating disease with complete collapse of the femoral head often reported in greater than 70% of patients within 3 to 4 years of diagnosis. Early intervention prior to collapse may improve the chance of success of joint preserving procedures.

QUESTIONS/PURPOSES

The purpose of this study was to evaluate whether core decompression with mesenchymal stem cells combined with bisphosphonate therapy can improve the clinical outcomes and reduce the risk of hip replacement when compared to treatment with bisphosphonate therapy alone.

METHODS

Between 2006 and 2014, 84 consecutive patients who were diagnosed with ONFH were identified from our institution's registry. Of these 84 patients, 49 patients (62 hips), fit inclusion/exclusion criteria. Twenty-nine patients (40 hips) were treated with bisphosphonate therapy only. Twenty patients (20 hips) were treated with bisphosphonates, core decompression, and mesenchymal stem cells. Functional outcomes were assessed using the Modified Harris Hip Score (MHHS), the visual analog score (VAS), and evaluation of support system. Clinical failure was defined as deterioration of the MHHS/VAS scores and support system used severe enough to require THR. Radiologic outcome measures included the XR and MR imaging staging of the hip. Survival analysis was performed with total hip replacement as the end point failure. Collapse was defined as progression from Ficat stage I or II to stage III and from Steinberg I, II, III to IV, V, VI.

RESULTS

Failure requiring THR occurred in 21/40 (52.5%) of bisphosphonates (BP)-treated hips at a mean follow-up of 25.3 ± 11.5 months and 5/22 (22.73%) of BP + CD + MSC-treated hips at a mean follow-up of 22.7 ± 19.5 months. The median (Q1, Q3) time to collapse was 24.9 (7.4, 33.0) months in BP-treated hips and 27.3 (27.3) months in BP + CD + MSC-treated hips. There was no evidence of a difference in functional outcomes between the two treatment groups. After adjusting for baseline Ficat stage, age, and sex, an unreplaced hip treated with BP + CD + MSC had 0.42 (95% CI 0.11, 1.57) times the risk of being replaced in the next moment compared to an unreplaced hip treated with bisphosphonates only (P = 0.196).

CONCLUSION

Our results demonstrate that treatment with BP alone or BP + CD + MSC can postpone the need for total hip arthroplasty (THA) in the first 24 months in patients with ONFH compared to previously reported data, but there is no statistically significant difference between the two treatment groups. Combination therapy of BP + CD + MSC may be more effective in delaying the progression of collapse in early stage ONFH. Future prospective studies are warranted to determine the efficacy of these treatment strategies in the long term.

From the radiologic pathology archives imaging of osteonecrosis: radiologic-pathologic correlation

Osteonecrosis is common and represents loss of blood supply to a region of bone. Common sites affected include the femoral head, humeral head, knee, femoral/tibial metadiaphysis, scaphoid, lunate, and talus. Symptomatic femoral head osteonecrosis accounts for 10,000-20,000 new cases annually in the United States. In contradistinction, metadiaphyseal osteonecrosis is often occult and asymptomatic. There are numerous causes of osteonecrosis most commonly related to trauma, corticosteroids, and idiopathic. Imaging of osteonecrosis is frequently diagnostic with a serpentine rim of sclerosis on radiographs, photopenia in early disease at bone scintigraphy, and maintained yellow marrow at MR imaging with a serpentine rim of high signal intensity (double-line sign) on images obtained with long repetition time sequences. These radiologic features correspond to the underlying pathology of osseous response to wall off the osteonecrotic process and attempts at repair with vascularized granulation tissue at the reactive interface. The long-term clinical importance of epiphyseal osteonecrosis is almost exclusively based on the likelihood of overlying articular collapse. MR imaging is generally considered the most sensitive and specific imaging modality both for early diagnosis and identifying features that increase the possibility of this complication. Treatment subsequent to articular collapse and development of secondary osteoarthritis typically requires reconstructive surgery. Malignant transformation of osteonecrosis is rare and almost exclusively associated with metadiaphyseal lesions. Imaging features of this dire sequela include aggressive bone destruction about the lesion margin, cortical involvement, and an associated soft-tissue mass. Recognizing the appearance of osteonecrosis, which reflects the underlying pathology, improves radiologic assessment and is important to guide optimal patient management.

Combining Concentrated Autologous Bone Marrow Stem Cells Injection With Core Decompression Improves Outcome for Patients with Early-Stage Osteonecrosis of the Femoral Head: A Comparative Study

The management of early-stage osteonecrosis of the femoral head (ONFH) remains challenging. This study aimed to evaluate the effects of core decompression and concentrated bone marrow implantation on ONFH. The study recruited 28 hips with early ONFH randomly assigned into two groups of core decompression with (group A) and without (group B) bone marrow injection. Patients were evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire, Visual Analogue Scale (VAS) pain index, and MRI. The mean WOMAC and VAS scores in all patients improved significantly (P<0.001). MRI showed a significant improvement in group A (P=0.046) and significant worsening in group B (P<0.001). Bone marrow stem cell injection with core decompression can be effective in early ONFH.

Repair effect of coexpression of the hVEGF and hBMP genes via an adeno-associated virus vector in a rabbit model of early steroid-induced avascular necrosis of the femoral head

We investigated the repair effect of coexpression of the human vascular endothelial growth factor (hVEGF) and human bone morphogenetic protein (hBMP) genes via an adeno-associated virus (AAV) vector in a rabbit model of early steroid-induced avascular necrosis of the femoral head (SANFH). The following AAV vectors were constructed: AAV-green fluorescent protein, AAV-VEGF, AAV-BMP, and AAV-VEGF/BMP. The rabbit model was induced using lipopolysaccharide and methylprednisolone. Virus vector was injected into the core decompression region at a dose of 25 μL per side after core decompression operation in each group. hVEGF165 and BMP-7 expressions were determined by Western blotting and immunohistochemical staining, and the femoral head was examined by magnetic resonance image scan, histopathologic staining, ink vessel staining, microcomputed tomography scan, and biomechanical assessment to determine the repair effect. The vector AAV-VEGF/BMP successfully expressed hVEGF165 and BMP-7 at the gene and protein levels at 12 weeks after virus injection. The expression of hVEGF165 promoted metabolism of the necrotic region by inducing vessel formation. The expression of BMP-7 promoted osteogenesis by increasing the mineral density and biomechanical strength of the femoral head. The repair effect of the AAV-VEGF/BMP group was better than those of the AAV-VEGF and AAV-BMP groups in the rabbit early SANFH model. The AAV-VEGF/BMP vector improved the bone repair capacity of the necrotic femoral head by inducing angiogenesis and improving bone quality in the femoral head.

Hormonal therapy in oncology: a primer for the radiologist

OBJECTIVE

The purpose of this article is to provide a comprehensive imaging review of the common hormonal therapies used in oncology and the side effects associated with them.

CONCLUSION

Commonly used hormones in oncology include corticosteroids, somatostatin analogues, progestins, gonadotropin-releasing hormone agonists and antagonists, antiandrogens, aromatase inhibitors, and selective estrogen receptor modulators. Familiarity with these hormones and their side effects can help radiologists to be vigilant for the side effects and complications of these agents.

Comparison of core decompression and conservative treatment for avascular necrosis of femoral head at early stage: a meta-analysis

The purpose of the current meta-analysis was to compare the efficacy of core decompression (CD) and conservative treatment (CT) for saving femoral heads in patients with avascular necrosis of femoral head (ANFH). Four RCTs and two CCTs involving 323 hips with 24- to 48-months follow-up were included in this review. Our results suggested CD had a trend of favorable results in contrast to other CT (OR 3.28; 95% CI 0.77-14.02; P = 0.11) but saved much less hips compared to biophysical treatments [odds ratio (OR) 0.37; 95% CI 0.18-0.74; P = 0.005]. In the stratified survival rate analysis by ANFH stage, interestingly, CD group got a significantly higher successful rate of hip joint conservation than other CT group in both stage I and stage II-III (stage I: OR 4.43; 95% CI 1.34-14.65; P = 0.01; stage II-III: OR 6.75; 95% CI 2.18-20.90; P = 0.0009). In the biophysical stimulation subgroup, however, an even higher frequency of survived hips were observed compared to CD group at stage II-III (CD vs. biophysical stimulation: OR 0.34; 95% CI 0.17-0.67; P = 0.002). In conclusion, performing CD for ANFH is effective for preventing femoral collapse within a short-term follow-up, but an even higher successful rate were expected by biophysical stimulations. Nevertheless, the short-term follow-up, the small sample size of the current meta-analysis only provide limited quality of evidence, which required confirmation from further large-scale, well-designed RCT with longer follow-up.

Conservative surgery for the treatment of osteonecrosis of the femoral head: current options

The prevention of femoral head collapse and the maintenance of hip function would represent a substantial achievement in the treatment of osteonecrosis of the femoral head; however it is difficult to identify appropriate treatment protocols to manage patients with pre-collapse avascular necrosis in order to obtain a successful outcome in joint preserving procedures. Conservative treatments, including pharmacological management and biophysical modalities, are not supported by any evidence and require further investigation. The appropriate therapeutic approach has not been identified. The choice of surgical procedures is based on patient clinical conditions and anatomopathological features; preservation of the femoral head by core decompression may be attempted in younger patients without head collapse. Biological factors, such as bone morphogenetic proteins and bone marrow stem cells, would improve the outcome of core decompression. Another surgical procedure proposed for the treatment of avascular necrosis consists of large vascularized cortical bone grafts, but its use is not yet common due to surgical technical issues. Use of other surgical technique, such as osteotomies, is controversial, since arthroplasty is considered as the first option in case of severe femoral head collapse without previous intervention.