Alcohol intake and the risk of osteonecrosis of the femoral head in Japanese populations: a dose-response meta-analysis of case-control studies

Etiology, pathology, and treatment of osteonecrosis of the femoral head in adolescents: A comprehensive review

Femoral head necrosis is a common refractory disease in orthopedics, and shows a trend of getting younger. The occurrence of femoral head necrosis in adolescents is related to the use of glucocorticoids, autoimmune diseases, trauma, and other factors. Because adolescent patients are in the period of physical development, high activity requirements, and have fertility needs in the future, treatment is relatively difficult. Early artificial joint replacement may have problems such as wear and loosening, so total hip replacement is not the preferred treatment for adolescent patients with femoral head necrosis. This article will elaborate the research progress of femoral head necrosis in adolescents from 3 aspects, and summarize the benefits and side effects of core decompression combined with autologous stem cell transplantation in the treatment of early femoral head necrosis, so as to provide clinical ideas for the treatment of femoral head necrosis in adolescents.

The association of alcohol use disorder with revision rates and post-operative complications in total shoulder arthroplasty

Background

Alcohol use disorder (AUD) is the most prevalent substance use disorder in the United States. However, the current literature on AUD as a preoperative risk factor for Total Shoulder Arthroplasty (TSA) outcomes is limited. The purpose of this study was to identify the association of AUD with revision rates and 90-day postoperative complications in TSA.

Methods

A retrospective study was conducted using the PearlDiver database. Patients diagnosed with AUD were identified. Patients in remission or with underlying cirrhosis were excluded. Outcomes included 2-year revision, 90-day readmission, 90-day emergency, and 90-day post-operative medical complications. Analysis was performed with univariate chi-squared tests followed by multivariable logistic regression.

Results

A total of 59,261 patients who underwent TSA for osteoarthritis were identified, with 1522 patients having a diagnosis of AUD. Multivariable logistic regression showed that patients with AUD were more likely to undergo 2-year all-cause revision (OR = 1.49, p  =  0.007), 2-year aseptic revision (OR = 1.47, p  =  0.014), 90-day hospital readmission (OR = 1.57, p  =  0.015), and 90-day transient mental disorder (OR = 2.13, p  =  0.026).

Conclusions

AUD is associated with increased rates of 2-year revision surgery, as well as 90-day readmission and 90-day transient mental disorder following primary TSA for osteoarthritis. These findings may assist orthopedic surgeons in counseling patients with AUD during the pre-operative course.

The Multiplicative Effects of Individual Risk Factors in the Development of Osteonecrosis of the Femoral Head

BACKGROUND

While individual risk factors, including chronic corticosteroid use, alcohol abuse, and smoking, are implicated in osteonecrosis of the femoral head (ONFH), the degree to which multiple risk factors increase risk is unknown. This study aimed to: (1) identify the demographic characteristics of patients who have ONFH; (2) quantify the effects of individual risk factors on ONFH development; (3) quantify the effects of combined risk factors on ONFH development; and (4) determine the prognostic implications of combined risk factors on ONFH development.

METHODS

This was a retrospective cohort study. A national insurance database was used to study a population of 2,612,383 adult patients who had a 10-year follow-up period. There were 10,233 patients identified who had a diagnosis of ONFH. We identified patients who had chronic corticosteroid use, tobacco use, and/or alcohol abuse and assessed the risk of developing ONFH over a 10-year period. Patients who had individual and multiple risk factors were grouped for comparison, and Chi-square analyses were performed.

RESULTS

Higher proportions of patients who had each individual risk factor developed ONFH compared to proportions of patients who did not have risk factors. Patients who had combined risk factors were at greater risk of developing ONFH compared to patients who had no risk factors and those who had single risk factors. Combined risk factors demonstrated multiplicative effects on the development of ONFH: tobacco-alcohol risk ratio (RR) 5.25, corticosteroid-alcohol RR 10.20, tobacco-corticosteroid RR 8.69, and corticosteroid-tobacco-alcohol RR 12.54. Patients who had combined risk factors developed ONFH at younger ages than those who had single risk factors. Kaplan-Meier curve analyses demonstrated worse 10-year hip survival in the setting of combined risk factors.

CONCLUSIONS

Combined risk factors have a multiplicative effect on the risk of developing of atraumatic ONFH. Orthopaedic surgeons may care for at-risk individuals through modulation of risk factors.

LEVEL OF EVIDENCE

Retrospective Cohort Study, Level III.

Predicting efficacy and guiding procedure choice in non-vascularized bone grafting: a CT Radiomics and clinical predictor approach

OBJECTIVES

There is no practical approach for accurately predicting the efficacy of non-vascularized bone grafting (NVBG) and guiding its optimal procedure.

MATERIALS AND METHODS

This study enrolled 153 patients with 182 hips that underwent NVBG procedures. The patients were randomly divided into a training cohort (n = 130) and a validation cohort (n = 52). In the training cohort, radiomics model, clinical model, and combined radiomics-clinical (C-R) model were constructed using Rad-scores and clinical predictors to predict the efficacy of NVBG. The optimal model was visualized by a nomogram and assessed by decision curve analysis (DCA). 128 hips that underwent successful NVBG were then randomized into a new training cohort (n = 92) and a new validation cohort (n = 36), and three models were constructed and validated to predict the choice of NVBG procedure.

RESULTS

Japanese Investigation Committee (JIC) classification, exposure to risk factors postoperative, and Rad-scores consisting of four radiomics features were independent predictors for the efficacy of NVBG (P < 0.05). The C-R model provided better performance in both the training cohort (AUC: 0.818) and validation cohort (AUC: 0.747). To predict the choice of NVBG procedure, the C-R model built by JIC classification and Rad-scores consisting of five radiomics features showed the finest performance in both cohorts (AUC: 0.860 and 0.800, respectively). DCA showed great benefit using the C-R model for the choice of NVBG procedure.

CONCLUSION

The approach integrated by CT radiomics and clinical predictors can be visually and quantitatively applied to predict the efficacy and guide the choice of NVBG procedure with great predictive accuracy.

The Lnc-HOTAIR/miR122/PPARγ signaling mediated the occurrence and continuous development of alcohol-induced Osteonecrosis of the femoral head

This study aimed to explore the mechanism of alcohol-induced Osteonecrosis of the femoral head (ONFH) through in vivo and in vitro experiments. In vitro, the Oil Red O staining showed that ethanol promoted extracellular adipogenesis in a dose-dependent manner. ALP staining and alizarin red staining showed that ethanol inhibited the formation of extracellular mineralization in a dose-dependent manner. The Oil Red O staining showed that miR122 mimics and Lnc-HOTAIR SiRNA rescued extracellular adipogenesis induced by ethanol in BMSCs. Besides, we found that the high expression of PPARγ in BMSCs recruited histone deacetylase 3 (HDAC3) and histone methyltransferase (SUV39H1), which reduced the histone acetylation level and increased the histone methylation level in the miR122 promoter region, respectively. In vivo, the levels of H3K9ac, H3K14ac, and H3K27ac of miR122 promoter region in the ethanol group were significantly decreased compared to the control group, respectively. The levels of H3K9me2 and H3K9me3 of miR122 promoter region in the ethanol group were significantly increased compared to the control group. Lnc-HOTAIR/miR-122/PPARγ signaling mediated the alcohol-induced ONFH in the rat model. Furthermore, the persistent decrease of miR122 expression mediated the continuous progress of alcohol-induced ONFH after stopping alcohol consumption.

[Progress of pathogenesis and genetics of alcohol-induced osteonecrosis of femoral head]

OBJECTIVE

To review the research progress of pathogenesis and genetics of alcohol-induced osteonecrosis of the femoral head (AIONFH).

METHODS

The relevant domestic and foreign literature in recent years was extensively reviewed. The pathogenesis, the relationship between gene polymorphism and susceptibility, the related factors of disease progression, and the potential therapeutic targets of AIONFH were summarized.

RESULTS

AIONFH is a refractory orthopedic disease caused by excessive drinking, seriously affecting the daily life of patients due to its high disability rate. The pathogenesis of AIONFH includes lipid metabolism disorder, endothelial dysfunction, bone homeostasis imbalance, and et al. Gene polymorphism and non-coding RNA are also involved. The hematological and molecular changes involved in AIONFH may be used as early diagnostic markers and potential therapeutic targets of the disease.

CONCLUSION

The pathogenesis of AIONFH has not been fully elucidated. Research based on genetics, including gene polymorphism and non-coding RNA, combined with next-generation sequencing technology, may provide directions for future research on the mechanism and discovery of potential therapeutic targets.

Avascular Necrosis of the Hip: A Post COVID-19 Sequela

A 60-year-old African American male presented to the hospital with seven months of progressively worsening left anterior hip pain with no known trauma. Two months after the pain onset, he underwent an x-ray of the pelvis with the lateral left hip, revealing dystrophic soft tissue calcification adjacent to the superolateral left acetabulum. Pain at this time was attributed to presumed sciatica vs arthritis. The patient underwent multimodal treatment for his pain without relief. In the month prior to the presentation, the patient also developed right hip pain. He then underwent a bilateral hip x-ray, revealing left femoral neck lucency suspicious for a nondisplaced fracture. CT pelvis was ordered at this time for further evaluation and demonstrated bilateral subcapital hip fractures. He was subsequently discharged from the emergency department with pending laboratory work and plans for close outpatient orthopedic surgery follow-up. The following day, the patient was instructed to return to the hospital due to an elevated erythrocyte sedimentation rate of 39 mm/hr and C-reactive protein of 41.6 mg/L. Subsequent MRI pelvis revealed bilateral subcapital femoral neck fractures with avascular necrosis (AVN) requiring surgical intervention with bilateral hip arthroplasty. Our patient underwent an extensive workup with no evidence of traditional risk factors for osteonecrosis, osteopenia, or other bone diseases. A pertinent finding in the patient's history was an admission for severe SARS-CoV-2 (COVID-19) infection 10 months prior. 'Long COVID' is a complex illness that has been shown to affect intravascular blood flow, and likely contributed to the development of bilateral hip AVN in our patient. Given this novel presentation, it is crucial that AVN be considered early in evaluating anterior hip pain for patients with a history of COVID-19 infection in order to avoid severe consequences such as femoral neck fractures.

PFKP and GPC6 Variants Were Correlated with Alcohol-Induced Femoral Head Necrosis Risk in the Chinese Han Population

Background

Osteonecrosis of the femoral head (ONFH) is a common joint disease caused by excessive drinking, genetic factors, etc. The purpose of this study was to investigate the association between PFKP and GPC6 variants and alcohol-induced ONFH (AIONFH) risk in the Chinese Han population.

Methods

This study genotyped 9 selected single nucleotide polymorphisms (SNPs) in 402 males by Agena MassARRAY Assay. By calculating odds ratios (ORs) and 95% confidence intervals (CIs), we assessed the effect of gene polymorphisms on AIONFH occurrence. False-positive report probability (FPRP) analysis and power were also used to evaluate the significant results. Multifactor dimensionality reduction (MDR) software was also utilized to predict the association between the selected SNPs and AIONFH risk.

Results

The overall analysis showed that PFKP rs10903966 and GPC6 rs7320969 were correlated with AIONFH risk. GPC6 rs4773724 was associated with a reduced risk of AIONFH, while individuals with GPC6 rs9523981 CC genotype had a higher risk of AIONFH than individuals with the other genotypes among people under 42 years old. Based on stratified analysis of necrotic sites, rs7320969 was related to a decreased risk of AIONFH, while rs10903966 and rs9523981 were related to an increased risk of AIONFH. In addition, rs1008993 and rs7320969 were observed to be linked to AIONFH risk in patients at different clinical stages. Meanwhile, there were significant differences in TC, TG, platelet, ApoA1 and ApoB levels among subjects with different genotypes of rs1008993, rs9523981, rs7320969 and rs59624626. The results of MDR showed that rs11251720 and rs7320969 may play a synergistic role in predicting the risk of AIONFH.

Conclusion

PFKP rs10903966 and GPC6 rs9523981 were associated with an increased risk of AIONFH, while GPC6 (rs7320969 and rs4773724) were correlated with a decreased risk of AIONFH. This result will need further experiments to verify.

FTO rs62033406 A>G associated with the risk of osteonecrosis of the femoral head among the Chinese Han population

BACKGROUND

Fat mass and obesity-related (FTO) mRNA was downregulated in osteonecrosis patients. The study aimed to evaluate the correlation between FTO polymorphisms and the susceptibility of osteonecrosis of the femoral head (ONFH).

METHODS

Six polymorphisms in FTO were genotyped via the Agena MassARRAY in 498 ONFH patients and 498 healthy controls. Multiple genetic models were used to assess the correlation between FTO polymorphisms and ONFH risk by SNPStats. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using a logistic regression model adjusted by age, gender, smoking and drinking.

RESULTS

The risk-increasing association of rs62033406 A>G with ONFH was found (OR = 1.25, 95% CI 1.05-1.50, p = 0.014). Specially, FTO rs62033406 A>G was related to the risk of ONFH in the subgroup at age > 51 years (OR = 1.25, p = 4.00 × 10^-4), females (OR = 1.74, p = 1.00 × 10^-4), smokers (OR = 1.82, p = 0.005) and drinkers (OR = 1.89, p = 0.002), respectively. The best multi-loci model was the five-loci model, a combination of rs9930333 T>G, rs1558902 T>A, rs56094641 A>G, rs3751812 G>T, and rs62033406 A>G (testing accuracy, 0.5351; p = 0.0004; cross-validation consistency, 10/10).

CONCLUSION

Our study first revealed that FTO rs62033406 A>G was a risk factor for ONFH among the Chinese Han population, which might provide the new candidate gene for elucidating the pathogenesis of ONFH.

The polymorphisms of MIR31HG gene is correlated with alcohol-induced osteonecrosis of the femoral head in Chinese Han male population

BACKGROUND

Alcoholic osteonecrosis of the femoral head (ONFH) is a multifaceted illness that seriously disturbs the patients' quality of life. The role of lncRNAs in alcoholic ONFH has attracted widespread attention in recent years. This study mainly explored whether MIR31HG polymorphism affects the risk of ONFH.

METHODS

There were 733 males (308 alcohol-induced ONFH patients and 425 healthy controls). Seven single nucleotide polymorphisms from MIR31HG were genotyped using the Agena MassARRAY platform. Odds ratio (OR) and 95% confidence intervals (CI) via logistic regression was applied to assess the contribution of MIR31HG variants to alcoholic ONFH susceptibility.

RESULTS

We found that rs10965059 was related to a lower risk of alcoholic ONFH in the overall, age, and necrotic sites analysis. Rs10965064 also showed a risk-reducing effect in the occurrence of alcoholic ONFH patients older than 40 years old.

CONCLUSIONS

We confirmed that MIR31HG variants have a significant correlation with the occurrence of alcoholic ONFH among the Chinese Han male population. our findings may provide new ideas for understanding the effect of MIR31HG on the prevention and diagnosis of alcoholic ONFH.

Effect of L3MBTL3/PTPN9 polymorphisms on risk to alcohol-induced ONFH in Chinese Han population

PURPOSE

Alcohol-induced osteonecrosis femoral head necrosis (ONFH) is a disease that seriously affects human health. Abnormal expression of L3MBTL3/PTPN9 gene can cause a variety of human diseases. The purpose of this study is to investigate the effect of L3MBTL3/PTPN9 gene polymorphism on the susceptibility of alcohol-induced ONFH in Chinese Han population.

METHODS

A total of 308 alcohol-induced ONFH patients and 425 healthy controls were enrolled in this case-control study. Alleles, genotypes, genetic models, haplotypes, and multifactor dimensionality reduction analyses (MDR) based on age-corrected by using odds ratio (OR) and 95% confidence interval (CI) were performed.

RESULTS

Our result revealed rs2068957 in the L3MBTL3 gene increased the risk of alcohol ONFH under the recessive model after correction. Besides, we also found that rs75393192 in the PTPN9 gene was a protective site in stratification over 40 years of age and stage. In stratified analysis of necrotic sites, we only found that rs2068957 was associated with increased susceptibility of alcohol-induced ONFH under the co-dominant model and recessive model. Haplotype "GC" in the block (rs76107647|rs10851882 in PTPN9 gene) significantly decreased the susceptibility of alcoholic ONFH.

CONCLUSIONS

Our results provide evidence that L3MBTL3/PTPN9 polymorphisms are associated with alcohol-induced ONFH risk in Chinese Han population.

Prevalence of avascular necrosis in idiopathic inflammatory myositis: a single center experience

OBJECTIVES

To assess the prevalence of avascular necrosis (AVN) in a large cohort of patients with idiopathic inflammatory myopathies (IIM) and define the major associated risk factors.

METHODS

We retrospectively reviewed the electronic medical records of all patients with a definitive diagnosis of IIM enrolled in our registry between 2003-2017 and followed until 2020. Pertinent demographic, clinical, serologic and imaging data were collected. A matched group of patients without AVN was then selected for comparison.

RESULTS

1680 patients were diagnosed with IIM. Fifty-one patients developed AVN, with an overall prevalence of 3%. Musculoskeletal magnetic resonance imaging (MSK MRI) was available for 1085 patients and AVN was present in 46 patients (43 lower extremities and 3 upper extremities MRI studies), with a relative prevalence of 4.2%. Most patients with AVN were Caucasian females (57%) with a mean age at diagnosis of 44.5 ± 12.4 years. 61% had dermatomyositis (DM) and 29% had polymyositis (PM). The median time from onset of IIM to diagnosis of AVN was 46 months. The hip joint was most commonly involved in 76% of cases, followed by the knee joint in 15% and shoulder joint in 9%. 81% of patients were asymptomatic. Established risk factors for AVN were not found to be associated with the development of AVN in IIM patients.

CONCLUSION

Although mostly asymptomatic and incidental, the overall prevalence of AVN in IIM was 3% and the prevalence by MRI was 4.2%. None of the established risk factors were found to be associated with AVN development.

Inflammation, Bone Healing and Osteonecrosis: From Bedside to Bench

Osteonecrosis of the epiphyseal and metaphyseal regions of major weight-bearing bones of the extremities is a condition that is associated with local death of bone cells and marrow in the afflicted compartment. Chronic inflammation is a prominent feature of osteonecrosis. If the persistent inflammation is not resolved, this process will result in progressive collapse and subsequent degenerative arthritis. In the pre-collapse stage of osteonecrosis, attempt at joint preservation rather than joint replacement in this younger population with osteonecrosis is a major clinical objective. In this regard, core decompression, with/without local injection of bone marrow aspirate concentrate (BMAC), is an accepted and evidence-based method to help arrest the progression and improve the outcome of early-stage osteonecrosis. However, some patients do not respond favorably to this treatment. Thus, it is prudent to consider strategies to mitigate chronic inflammation concurrent with addressing the deficiencies in osteogenesis and vasculogenesis in order to save the affected joint. Interestingly, the processes of inflammation, osteonecrosis, and bone healing are highly inter-related. Therefore, modulating the biological processes and crosstalk among cells of the innate immune system, the mesenchymal stem cell-osteoblast lineage and others are important to providing the local microenvironment for resolution of inflammation and subsequent repair. This review summarizes the clinical and biologic principles associated with osteonecrosis and provides potential cutting-end strategies for modulating chronic inflammation and facilitating osteogenesis and vasculogenesis using local interventions. Although these studies are still in the preclinical stages, it is hoped that safe, efficacious, and cost-effective interventions will be developed to save the host’s natural joint.

Simultaneous Bilateral Avascular Necrosis of the Femoral Heads Associated With Cocaine Use

We present a case of a 38-year-old female patient, presenting with debilitating simultaneous bilateral avascular necrosis of the femoral head (AVNFH) 10 years after cocaine detoxification, making her wheelchair-bound for six months. This case is reported for the rarity of association of cocaine with AVNFH, and for the unique fact of the simultaneous bilateral condition occurring a long time after cocaine ingestion in the absence of other important risk factors.

This report postulates cocaine as a possible cause of bilateral AVNFH, which can increase the index of suspicion of this pathology, allowing early diagnosis and better outcomes.

Osthole stimulates bone formation, drives vascularization and retards adipogenesis to alleviate alcohol-induced osteonecrosis of the femoral head

Characteristic pathological changes in osteonecrosis of the femoral head (ONFH) include reduced osteogenic differentiation of bone mesenchymal stem cells (BMSCs), impaired osseous circulation and increased intramedullary adipocytes deposition. Osthole is a bioactive derivative from coumarin with a wide range of pharmacotherapeutic effects. The aim of this study was to unveil the potential protective role of osthole in alcohol‐induced ONFH. In vitro, ethanol (50 mmol/L) remarkably decreased the proliferation and osteogenic differentiation of BMSCs and impaired the proliferation and tube formation capacity of human umbilical vein endothelial cell (HUVECs), whereas it substantially promoted the adipogenic differentiation of BMSCs. However, osthole could reverse the effects of ethanol on osteogenesis via modulating Wnt/β‐catenin pathway, stimulate vasculogenesis and counteract adipogenesis. In vivo, the protective role of osthole was confirmed in the well‐constructed rat model of ethanol‐induced ONFH, demonstrated by a cascade of radiographical and pathological investigations including micro‐CT scanning, haematoxylin‐eosin staining, TdT‐mediated dUTP nick end labelling, immunohistochemical staining and fluorochrome labelling. Taken together, for the first time, osthole was demonstrated to rescue the ethanol‐induced ONFH via promoting bone formation, driving vascularization and retarding adipogenesis.

Betaine alleviates alcohol-induced osteonecrosis of the femoral head via mTOR signaling pathway regulation

Osteonecrosis of the femoral head (ONFH) is usually caused by chronic and excessive alcohol dependency, and this condition largely suppresses the osteogenic differentiation of bone mesenchymal stem cells (BMSCs). As a trimethyl derivative of glycine, betaine is an important human nutrient that regulates a series of vital biological processes, including oxidative stress, inflammatory responses, osteoblast differentiation and cellular apoptosis. However, no study has investigated the role of betaine in alcohol-induced ONFH. In this study, we hypothesized that betaine might have protective effects on ethanol-treated BMSCs and decrease the morbidity of alcohol-induced ONFH in a rat model. In vitro, we found that ethanol significantly downregulated the expression of osteocalcin (OCN), collagen 1 (COL1) and RUNX2 via activating the mammalian target of rapamycin (mTOR) signaling cascade. However, the inhibitory effects were rescued by betaine co-treatment at concentrations of 1 mM and 10 mM. In vivo, the typical ONFH pathological changes in a rat model of alcohol-induced ONFH were investigated by using multiple methods, including hematoxylin-eosin staining, micro-CT scans, TdT-mediated dUTP nick end labeling (TUNEL) assays and immunohistochemical staining for OCN and COL1. Osteonecrotic lesions of the femoral head could be alleviated by betaine as evidenced by significant histological and radiological improvements. Collectively, betaine plays a protective role against ethanol-induced suppression of osteogenesis and mineralization of hBMSCs and is thus a potential pharmacotherapy for alcohol-induced ONFH in vivo.

A comparative study of cortico-cancellous iliac bone graft with or without the combination of vascularized greater trochanter flap for the management of femoral head osteonecrosis: a minimum 6 years follow-up

BACKGROUND

To compare the mid-long-term clinical and radiological outcomes between a combination of cortico-cancellous iliac bone graft with vascularized greater trochanter flap (Group A) and isolate iliac bone graft (Group B) in the treatment of Osteonecrosis of the Femoral Head (ONFH).

METHODS

From January 2006 to December 2012, 123 patients (135 hips) who underwent abovementioned hip-preserving surgeries were included for analysis. Clinical outcomes were assessed based on Harris Hip Score (HHS) System and The Western Ontario and McMaster University Index (WOMAC) scores between the preoperative and the last follow-up. A series of postoperative X-rays were compared to preoperative images for radiological evaluation.

RESULTS

The HHS in Group A and B were enhanced from 50.57 ± 3.39 to 87.60 ± 4.15 and from 50.24 ± 3.30 to 85.18 ± 6.45, respectively, which both showed significance between preoperative and postoperative latest follow-up (p < 0.001). Group A revealed better improvement in terms of HHS (p = 0.017). The WOMAC total, postoperative stiffness, difficulty subscale scores in Group A showed better outcomes when compared to Group B (p < 0.01), while pain improvement between these two groups revealed no significance (p = 0.402). Besides, Group A suggested better necrotic region repair (p = 0.020), but no femoral head collapse difference in terms of Association Research Circulation Osseous classification change was found (p > 0.05).

CONCLUSIONS

A combination of cortico-cancellous iliac bone graft and concurrent vascularized greater trochanter flap with the lateral femoral circumflex transverse branch has been proved can obtain better functional and radiological results than isolate iliac bone grafting, which is attributed to blood reconstruction of the femoral head.

Osteonecrosis of the femoral head: pathophysiology and current concepts of treatment

Osteonecrosis of the femoral head is a disabling pathology affecting a young population (average age at treatment, 33 to 38 years) and is the most important cause of total hip arthroplasty in this population. It reflects the endpoint of various disease processes that result in a decrease of the femoral head blood flow.The physiopathology reflects an alteration of the vascularization of the fine blood vessels irrigating the anterior and superior part of the femoral head. This zone of necrosis is the source of the loss of joint congruence that leads to premature wear of the hip.Several different types of medication have been developed to reverse the process of ischemia and/or restore the vascularization of the femoral head. There is no consensus yet on a particular treatment.The surgical treatments aim to preserve the joint as far as the diagnosis could be made before the appearance of a zone of necrosis and the loss of joint congruence. They consist of bone marrow decompressions, osteotomies around the hip, vascular or non-vascular grafts.Future therapies include the use of biologically active molecules as well as implants impregnated with biologically active tissue. Cite this article: EFORT Open Rev 2019;4:85-97. DOI: 10.1302/2058-5241.4.180036.

Epidemiology, Cause, and Anatomy of Osteonecrosis of the Foot and Ankle

Osteonecrosis arises throughout the foot and ankle in various forms and due to numerous causes, with a thousand US cases per year estimated for the ankle alone. Although research continues to elucidate specific mechanisms at work, the pathophysiology remains poorly understood. Nevertheless, the various osteonecrosis pathways converge on osteocyte death, and bony lesions follow a pattern of progression. Understanding the specific anatomy and biomechanics associated with common forms of foot and ankle osteonecrosis should help guide diagnosis and interventions, particularly at earlier stages of disease where etiology-specific approaches might become optimal.

Etiologic Classification Criteria of ARCO on Femoral Head Osteonecrosis Part 2: Alcohol-Associated Osteonecrosis

BACKGROUND

Although alcohol is a leading risk factor for osteonecrosis of the femoral head (ONFH) and its prevalence reportedly ranges from 20% to 45%, there are no unified classification criteria for this subpopulation. In 2015, Association Research Circulation Osseous decided to develop classification criteria for alcohol-associated ONFH.

METHODS

In June of 2017, Association Research Circulation Osseous formed a task force to conduct a Delphi survey. The task force invited 28 experts in osteonecrosis/bone circulation from 8 countries. Each round of the Delphi survey included questionnaires, analysis of replies, and feedback reports to the panel. After 3 rounds of the survey, consensus was reached on the classification criteria. The response rates for the 3 Delphi rounds were 100% (round 1), 96% (round 2), and 100% (round 3).

RESULTS

The consensus on the classification criteria of alcohol-associated ONFH included the following: (1) patients should have a history of alcohol intake >400 mL/wk (320 g/wk, any type of alcoholic beverage) of pure ethanol for more than 6 months; (2) ONFH should be diagnosed within 1 year after alcohol intake of this dose; and (3) patients should not have other risk factor(s).

CONCLUSION

ARCO-established classification criteria to standardize clinical studies concerning AA-ONFH.