[Research progress in surgical treatment of avascular necrosis of talus].

Objective: To summarize the surgical treatment methods for avascular necrosis of the talus. Methods: The recent domestic and international literature related to avascular necrosis of the talus was extensively conducted. The pathogenesis, surgical treatment methods, and prognosis were summarized. Results: The clinical symptoms of avascular necrosis of the talus at early stage are not obvious, and most patients have progressed to Ficat-Arlet stages Ⅲ-Ⅳ and require surgical treatment. Currently, surgical treatments for this disease include core decompression, vascularized bone flap transplantation, arthroplasty, and arthrodesis, etc. Early avascular necrosis of the talus can be treated conservatively, and if treatment fails, core decompression can be considered. Arthrodesis is a remedial surgery for patients with end-stage arthritis and collapse, and in cases of severe bone loss, tibiotalocalcaneal arthrodesis and bone grafting are required. Vascularized bone flap transplantation is effective and plays a role in all stages of avascular necrosis of the talus, but the appropriate donor area for the flap still needs further to be studied. Conclusion: The surgical treatment and the system of treatment for different stages of avascular necrosis of the talus still need to be refined.

Medication-related osteonecrosis of the jaw: evolving research for multimodality medical management.

PURPOSE: Medication-related osteonecrosis of the jaw (MRONJ) is a debilitating side effect of antiresorptive and antiangiogenic agents that can lead to progressive bone destruction in the maxillofacial region. Dental surgery, including tooth extractions, commonly trigger the onset of MRONJ. While guidelines suggest avoiding extraction when possible, complete avoidance is not always feasible, as necrosis can develop from dental and periodontal disease without dental procedures. The goal of this article is to provide an update review of current preventive and therapeutic approaches for MRONJ. METHODS: A comprehensive electronic search was conducted on PubMed/MEDLINE, Embase, and Scopus databases. All English articles encompassing randomized controlled trials, systematic reviews, observational studies, and case studies were reviewed. The current medical treatments and adjuvant therapies for managing MRONJ patients were critically assessed and summarized. RESULTS: Pentoxifylline and alpha tocopherol (PENT-E), teriparatide, photobiomodulation (PBM), photodynamic therapy (PDT), and the use of growth factors have shown to enhance healing in MRONJ patients. Implementing these methods alone or in conjunction with surgical treatment has been linked to reduced discomfort and improved wound healing and increased new bone formation. DISCUSSION: While several adjuvant treatment modalities exhibit promising results in facilitating the healing process, current clinical practice guidelines predominantly recommend antibiotic therapy as a non-surgical approach, primarily addressing secondary infections in necrotic areas. However, this mainly addresses the potential infectious complication of MRONJ. Medical approaches including PENT-E, teriparatide, PBM, and PDT can result in successful management and should be considered prior to taking a surgical approach. Combined medical management for both preventing and managing MRONJ holds potential for achieving optimal clinical outcomes and avoiding surgical intervention, requiring further validation through larger studies and controlled trials.

[Role and mechanism of macrophage-mediated osteoimmune in osteonecrosis of the femoral head].

Objective: To summarize the research progress on the role of macrophage-mediated osteoimmune in osteonecrosis of the femoral head (ONFH) and its mechanisms. Methods: Recent studies on the role and mechanism of macrophage-mediated osteoimmune in ONFH at home and abroad were extensively reviewed. The classification and function of macrophages were summarized, the osteoimmune regulation of macrophages on chronic inflammation in ONFH was summarized, and the pathophysiological mechanism of osteonecrosis was expounded from the perspective of osteoimmune, which provided new ideas for the treatment of ONFH. Results: Macrophages are important immune cells involved in inflammatory response, which can differentiate into classically activated type (M1) and alternatively activated type (M2), and play specific functions to participate in and regulate the physiological and pathological processes of the body. Studies have shown that bone immune imbalance mediated by macrophages can cause local chronic inflammation and lead to the occurrence and development of ONFH. Therefore, regulating macrophage polarization is a potential ONFH treatment strategy. In chronic inflammatory microenvironment, inhibiting macrophage polarization to M1 can promote local inflammatory dissipation and effectively delay the progression of ONFH; regulating macrophage polarization to M2 can build a local osteoimmune microenvironment conducive to bone repair, which is helpful to necrotic tissue regeneration and repair to a certain extent. Conclusion: At present, it has been confirmed that macrophage-mediated chronic inflammatory immune microenvironment is an important mechanism for the occurrence and development of ONFH. It is necessary to study the subtypes of immune cells in ONFH, the interaction between immune cells and macrophages, and the interaction between various immune cells and macrophages, which is beneficial to the development of potential therapeutic methods for ONFH.

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.

Osteonecrose dos maxilares relacionada ao uso demedicamentos: características patológicas, diagnóstico,prevenção e estratégias terapêuticas / Medication-related osteonecrosis of the jaws: pathological characteristics, diagnosis, prevention and therapeutic strategies

Objetivo: Este trabalho tem como propósito fornecer uma análise abrangente das características clínicas, etiológicas, radiográficas e histopatológicas da osteonecrose dos maxilares relacionada ao uso de medicamentos, além de abordar os métodos de diagnóstico, prevenção e estratégias terapêuticas. Materiais e métodos: foi realizada uma busca por artigos científicos publicados no período de 2015 a 2023, utilizando as bases de dados Scientific Electronic Library Online (SciELO), US National Library of Medicine (PubMed) e ScienceDirect. Conclusão: Embora infrequente, há um considerável potencial de ocorrência de osteonecrose dos maxilares em pacientes submetidos a terapia prolongada com medicamentos antirreabsortivos e antiangiogênicos, especialmente quando não são adotadas medidas preventivas adequadas. A implementação de práticas preventivas, a vigilância das condições bucais e a colaboração de uma equipe multidisciplinar são fundamentais para reduzir os riscos associados a essa condição patológica.(AU)

Objective: This work aims to provide a comprehensive analysis of the clinical, etiological, radiographic and histopathological characteristics of Medication-Related Jaw Osteonecrosis, in addition to addressing diagnostic methods, prevention and therapeutic strategies. Materials and methods: A search was carried out for scientific articles published between 2015 and 2023, using the Scientific Electronic Library Online (SciELO), US National Library of Medicine (PubMed) and ScienceDirect databases. Conclusion: Although infrequent, there is a considerable potential for osteonecrosis of the jaw to occur in patients undergoing prolonged therapy with antiresorptive and antiangiogenic medications, especially when adequate preventive measures are not adopted. The implementation of preventive practices, surveillance of oral conditions and the collaboration of a multidisciplinary team are essential to reduce the risks associated with this pathological condition.(AU)

Current management of avascular necrosis of the metacarpal head: a comprehensive literature review.

BACKGROUND: Avascular necrosis (AVN) of the metacarpal head is a rare disease that may lead to progressive destruction of the metacarpophalangeal joint and hand function. This study aimed to describe the epidemiology, possible risk factors, clinical presentation, diagnostic workup, and treatment of the rare condition of avascular necrosis of the metacarpal head. METHODS: Articles were searched using the subject words "Dieterich disease","Mauclaire's disease", and "avascular necrosis of metacarpal head" in the PubMed and Scopus databases. Studies were retained for review after meeting the inclusion criteria. Those outcomes relevant to diagnose and assessing AVN of the metacarpal head and those related to curative management were extracted. RESULTS: The literature search revealed 45 studies with 55 patients. Although the aetiology of osteonecrosis has not been clearly delineated, AVN of the metacarpal head most commonly arises from trauma but other risk factors may also be involved. Plain radiographs are often negative and therefore likely to be missed. Early-stage osteonecrosis of the metacarpal head was best assessed using MRI. Given the rarity of this condition, there is no clear consensus on the treatment. CONCLUSIONS: Avascular necrosis of the metacarpal head should be considered in the differential diagnosis of painful metacarpophalangeal joints. An early understanding of this unusual disease will provide an optimal clinical outcome, restoring joint activity, and resolving pain. Nonoperative treatment cannot cure all patients. Surgical management is based on the patient and lesion characteristics.

The efficiency of genetically modified mesenchymal stromal cells combined with a functionally graded scaffold for bone regeneration in corticosteroid-induced osteonecrosis of the femoral head in rabbits.

Core decompression (CD) with mesenchymal stromal cells (MSCs) is an effective therapy for early-stage osteonecrosis of the femoral head (ONFH). Preconditioning of MSCs, using inflammatory mediators, is widely used in immunology and various cell therapies. We developed a three-dimensional printed functionally graded scaffold (FGS), made of ß-TCP and PCL, for cell delivery at a specific location. The present study examined the efficacy of CD treatments with genetically modified (GM) MSCs over-expressing PDGF-BB (PDGF-MSCs) or GM MSCs co-over-expressing IL-4 and PDGF-BB and preconditioned for three days of exposure to lipopolysaccharide and tumor necrosis factor-alpha (IL-4-PDGF-pMSCs) using the FGS for treating steroid-induced ONFH in rabbits. We compared CD without cell-therapy, with IL-4-PDGF-pMSCs alone, and with FGS loaded with PDGF-MSCs or IL-4-PDGF-pMSCs. For the area inside the CD, the bone volume in the CD alone was higher than in both FGS groups. The IL-4-PDGF-pMSCs alone and FGS + PDGF-MSCs reduced the occurrence of empty lacunae and improved osteoclastogenesis. There was no significant difference in angiogenesis among the four groups. The combined effect of GM MSCs or pMSCs and the FGS was not superior to the effect of each alone. To establish an important adjunctive therapy for CD for early ONFH in the future, it is necessary and essential to develop an FGS that delivers biologics appropriately and provides structural and mechanical support.

A systematic review on the management of idiopathic avascular necrosis of the scaphoid (Preiser's disease).

BACKGROUND: Treatment options for patients with Preiser's disease are challenging and varied. This article thus provides a systematic review of existing studies on the outcomes of the treatments for patients suffering from Preiser's disease in order to investigate the most appropriate management of Preiser's in each stage of the disease. METHODS: We followed PRISMA guidelines while performing the study, and reviewed 107 papers in all languages from 1981 till November 2020 and included 42 studies that met the eligibility criterion. Studies investigating the outcome of one or more treatment options for Preiser's disease were eligible. Besides, quantitative analysis on 130 individuals (135 wrists) of the included studies was performed. RESULTS: The results show that in stages II and III, pain score reduces more in surgical approach than in conservative treatment. In stage II of the Preiser's, Vascularized Bone Grafting (VBG) was more effective in pain alleviation and improvement in wrist range of motion (ROM) and Mayo Modified Wrist Score (MMWS) than immobilization. Proximal Row Carpectomy (PRC) in stage III causes more pain relief and ROM improvement than VBG and conservative treatments like prescribing NSAIDs. Inconsistent evidence was found in case studies of stage IV; however, they generally favour PRC and SILASTIC implants. Surgical studies of stage I are not yet enough for making a conclusive assessment. CONCLUSION: Surgical treatment outcomes seem more satisfactory in all Preiser's disease stages. Specifically, VBG for patients of stage II provided they have no scaphoid degenerative changes, and PRC seems more satisfactory for stage III. LEVEL OF EVIDENCE: IV; systematic review of case reports and case series on Preiser's disease.

Frequency of osteonecrosis in bisphosphonate users submitted to dental procedures: A systematic review.

OBJECTIVE: To determine the frequency of osteonecrosis of the jaw in bisphosphonate users submitted to dental procedures. METHODS: This systematic review searched the sources: MEDLINE, EMBASE, Web of Science, Scopus, and Virtual Health Library, with no restriction on language or publication date. Reviewers, in pairs and independently, selected the studies, extracted their data, and assessed the risk of bias. Meta-analyses were pooled using the DerSimonian and Laird random effects model. RESULTS: A total of 27 studies (5391 participants) were included. The most reported bisphosphonates were zoledronate (n = 17 studies) and alendronate (n = 19) for treating cancers (n = 11) and osteoporosis (n = 16), respectively. Twelve studies were of low methodological quality. The frequency of osteonecrosis was 2.7% (95% CI: 0.9-5.2%) and proved higher for intravenous [6.9% (0.7-17.3%)] than oral [0.2% (0.9-5.2%)] bisphosphonate use. No association between longer treatment duration and greater frequency of osteonecrosis was observed. CONCLUSIONS: Higher frequency of osteonecrosis was observed in intravenous bisphosphonate users submitted to dental extraction. Further studies collecting more detailed information on the bisphosphonates used and of greater methodological rigor are warranted to confirm these findings and better inform prescribers, dental surgeons, and other professionals on risks of bisphosphonate use in this patient group.

Clinical Vignettes, Part II: Eyes, Teeth, and Bone.

Microvascular occlusions caused by sickle cell disease (SCD) can affect all ocular and orbital structures. Sickle cell retinopathy (SCR) is the most common ophthalmic manifestation of SCD. Fortunately, most individuals with SCR are visually asymptomatic. Vision loss in SCD most commonly occurs as a consequence of proliferative sickle cell retinopathy (PSR), in which pathologic retinal neovascularization occurs. To prevent significant vision loss and blindness, which can occur from complications of PSR, regular retinopathy surveillance screening examinations and consistent follow-up with a retina specialist are recommended. Scatter laser photocoagulation is the current gold-standard treatment to prevent vision threatening progression of PSR. Patients with sickle cell disease should have regular checkups with their dental care provider. Patients should be educated on the importance of proper dental care, a healthy diet, and the need for early intervention if they suspect any dental problems or are having dental pain. If any dental procedures that involve surgery or sedation are planned, it is critical to consult with the hematologist before the procedure is started. Prophylactic antibiotics may have to be prescribed before invasive dental procedures, such as extractions or periodontal surgery but is best determined by discussions between the dental care provider and the hematologist. Osteonecrosis is a highly prevalent skeletal complication of sickle cell disease that affects all genotypes. Risk factors for osteonecrosis include older age, HbSS genotype with concomitant alpha-thalassemia trait, frequent vaso-occlusive episodes, history of acute chest syndrome, elevated body mass index, and low white blood cell counts. Osteonecrosis causes progressive joint damage and associates with chronic pain, frequent acute care visits, and overall poor health-related quality of life. Current consensus guidelines recommend analgesics, physical therapy, and early consideration of joint arthroplasty in sickle cell-related osteonecrosis, although surgery may be deferred until late adolescence after growth plates have fused.

Precision Medicine for Kienböck Disease in the 21st Century.

One of the most popular treatment algorithms for Kienböck disease is based on a progression of successive radiographic changes that was developed in the 1970s. Since then, 2 other important classifications systems have been introduced. One is centered on contrasted magnetic resonance imaging findings and the other, articular cartilage degeneration. All 3 systems have been used, in isolation, to recommend specific treatment modalities. To coordinate all available clinical data and to simplify the treatment selection process, we combined the 3 classification systems into 1 unified classification and treatment algorithm. With the added consideration of some recently introduced surgical options and further knowledge of how Kienböck disease affects children and the elderly, we anticipate that this unified classification system will allow for a more precise and individualized treatment plan.

Outcomes with culture-directed antibiotics following microvascular free tissue reconstruction for osteonecrosis of the jaw.

OBJECTIVES: Radiation (ORNJ) and bisphosphonate-related (BRONJ) osteonecrosis of the jaw represent challenging entities to treat, with many patients requiring segmental resection and reconstruction with microvascular free tissue transfer (MFTT) in the setting of failed conservative therapy. Microvascular reconstruction is associated with higher post-operative complication rates when performed for advanced osteonecrosis versus oncologic defects. We hypothesize that basing antibiotic therapy on cultures obtained from the healthy bone marrow following resection during MFTT for ORNJ or BRONJ reduces rates of post-operative wound and surgical complications. MATERIALS AND METHODS: In a retrospective cohort study spanning January 2016 to October 2018, 44 patients undergoing MFTT for ORNJ or BRONJ were identified. Patients were categorized into two cohorts: residual healthy marrow culture (n = 11; RHM), treated with antibiotics guided by cultures from healthy appearing mandible, and all others (n = 33; AO), treated with antibiotics guided by cultures from resected necrotic bone or purulent drainage. Patient, reconstruction, and outcome variables were compared via appropriate statistical tools. RESULTS: 81.8% of the RHM cohort versus 24.2% of the AO cohort received long-term IV antibiotics. Rates of post-operative wound complications, including those necessitating operative management, were significantly lower in the RHM cohort. Rates of flap failure were similar across both groups. CONCLUSION: Administration of long-term IV antibiotics directed by native mandible cultures may decrease complication rates following MFTT for ORNJ or BRONJ by treating residual, smoldering infection. Concurrently, transplantation of well-vascularized free tissue likely improves antibiotic delivery. Findings are crucial for the development of a standardized treatment algorithm following microvascular reconstruction for advanced osteonecrosis.

Extracorporeal shock wave therapy for the treatment of osteonecrosis and bone vascular diseases: a systematic review of randomized controlled trials.

OBJECTIVE: The aim of the study is to review the available literature on the use of Extracorporeal Shock Wave Therapy (ESWT) for the treatment of osteonecrosis (ON) and bone vascular disease (BVD), to understand its therapeutic potential and compare it with other therapies. MATERIALS AND METHODS: A systematic review was performed on the PubMed, Scopus, Science Direct, and Research Gate databases with the following inclusion criteria: 1) randomized controlled trials (RCTs); 2) written in English; 3) published in indexed journals within the last 25 years (1995-2020); and 4) dealing with the use of ESWT for the treatment of BVD or ON. The risk of bias was assessed by the Cochrane Risk of Bias tool for RCTs. RESULTS: Five studies involving 199 patients in total (68 female and 131 male) were included. Patients in the control groups received different treatments, like surgery, bisphosphonates in combination with prostacyclin or ESWT, and hyperbaric oxygen therapy. Looking at the quality of the available literature, none of the studies included could be considered a "good quality" study; only one was ranked as "fair" and the remaining were marked "poor" quality studies. No major complications or serious adverse events were reported in any of the included studies. Based on the available data, ESWT can produce rapid pain relief and functional improvement. CONCLUSIONS: Overall, a substandard quality of method emerged from the analysis of the literature, with most studies flawed by relevant bias. Ultimately, ESWT has the potential to be a useful conservative treatment in bone degeneration due to vascular and tissue turnover impairment.

Role of miR-214 in biomaterial transplantation therapy for osteonecrosis.

BACKGROUND: The effectiveness and availability of conservative therapies for osteonecrosis of the femoral head (ONFH) are limited. Transplantation of bone marrow mesenchymal stem cells (BMSCs) combined with Bio-Oss, which is a good bone scaffold biomaterial for cell proliferation and differentiation, is a new potential therapy. Of note, the expression of miRNAs was significantly modified in cells cultured with Bio-Oss, and MiR-214 was correlated positively with osteonecrosis. Furthermore, miR-214 was upregulated in cells exposed to Bio-Oss. OBJECTIVE: To investigate whether targeting miR-214 further improves the transplantation effect. METHODS: We treated BMSCs with agomiR-214 (a miR-214 agonist), antagomiR-214 (a miR-214 inhibitor), or vehicle, followed by their transplantation into ONFH model rats. RESULTS: Histological and histomorphometric data showed that bone formation was significantly increased in the experimental groups (Bio-Oss and BMSCs treated with antagomiR-214) compared with other groups. CONCLUSIONS: miR-214 participates in the inhibition of osteoblastic bone formation, and the inhibition of miR-214 to bone formation during transplantation therapy with Bio-Oss combined with BMSCs for ONFH.

Necrotising periodontal diseases and alcohol misuse - a cause of osteonecrosis?

'Necrotising periodontal diseases' is an umbrella term for necrotising gingivitis, necrotising periodontitis, necrotising stomatitis and noma. These rapidly destructive conditions are characterised by pain, interdental ulceration and gingival necrosis which, if left untreated, can result in osteonecrosis. Research indicates that patients with a history of alcohol misuse are at an increased risk of malnutrition, which negatively affects the immune response and predisposition to necrotising periodontal diseases. This article will discuss that osteonecrosis of the alveolar bone does not exclusively occur in association with antiresorptive medications, but can occur as a severe form of necrotising gingivitis. In this article, we will describe two cases to highlight the occurrence, presentation and management of necrotising periodontal diseases secondary to alcohol misuse.

Osteonecrosis of the Femoral Head: an Updated Review of ARCO on Pathogenesis, Staging and Treatment.

Non-traumatic osteonecrosis of the femoral head (ONFH) usually affects adults younger than 50 years and frequently leads to femoral head collapse and subsequent arthritis of the hip. It is becoming more prevalent along with increasing use of corticosteroids for the adjuvant therapy of leukemia and other myelogenous diseases as well as management of organ transplantation. This review updated knowledge on the pathogenesis, classification criteria, staging system, and treatment of ONFH.

Functional and Radiographic Disease Progression in Nonoperatively Managed Kienböck Disease.

BACKGROUND: The purpose of this study was to describe the natural history of Kienböck disease among patients who elected to proceed with nonoperative treatment. METHODS: The authors performed a retrospective study of all patients treated nonoperatively for Kienböck disease within their institution from January 1, 1999, to December 31, 2014. Inclusion criteria included follow-up greater than 1 year, serial posteroanterior and lateral wrist radiographs, and clinical examination. Posteroanterior/lateral radiographs were independently reviewed at initial presentation and at final follow-up, including Lichtman stage, carpal index, Stahl index, ulnar variance, and intercarpal angles. RESULTS: Twenty-five patients with 25 wrists were included (mean age, 50.2 years), with an average length of clinical follow-up of 3.9 years and a mean length of radiographic follow-up of 5.2 years. There was no significant difference in range of motion; however, patient-reported pain was significantly decreased, and modified Mayo wrist scores and grip strength were increased. Lichtman stage, scapholunate angle, and radioscaphoid angle were increased; and carpal index, posteroanterior lunate ratio, and Stahl index were decreased across the study period. The mean progression in Lichtman stage was 0.5 stage/year with a range of 0 to 1.6 stages/year throughout the study period. There was no significant difference in Lichtman stage progression based on stage at presentation. A history of smoking was associated with increased radiographic disease progression. CONCLUSION: The present study demonstrates that among patients with Kienböck disease managed nonoperatively, the majority of patients significantly improve over time with respect to pain, grip strength, and Mayo wrist score, despite radiographic progression of disease. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, IV.

Kienbock's Disease: Treatment Options - A Search for the Apt!

Kienbock's disease remains a condition of uncertain etiology and our understanding about the pathogenesis is still evolving. However, a lack of consensus on the treatment is the most striking as there are wide array of treatment options described ranging from 'doing nothing' to a free vascularized bone graft reconstruction of the lunate. Furthermore, most treatment modalities report equivalent success rate but cumulative evidence is lacking. This 'black hole' in the literature presents difficulties to surgeons treating the condition and even patient's confidence with the treatment. All the treatment options described reliably relieve pain, thus improving function and patient satisfaction. However, the disease process is not reliably altered by any of the treatment options described till date. The operative treatment chosen depends on the stage of the disease, ulnar variance, age of the patient and surgeon preference. The treatment options in early stage (before lunate collapse) aim to preserve the lunate while once the lunate is collapsed its removal is performed. The lunate preserving operations basically are either decreasing the load on the lunate to possibly permit its revascularization or are the procedures which are aimed at augmenting the vascularity of the lunate. Radius shortening osteotomy is the most popular treatment in the early stages especially in the patients' with negative ulnar variance and the proximal row carpectomy is most popular in the advanced stages of the disease. Authors present their algorithm of management of Kienbock's disease and discuss the various treatment options described in the literature in an attempt to find the apt in 2020.

Preiser's disease or avascular osteonecrosis of the scaphoid: An updated literature review.

Avascular necrosis of the scaphoid, often referred to as Preiser's disease, is little known despite the scaphoid being the second most frequently involved location in avascular pathology of the carpal bones after the lunate (Kienböck's disease). Nonetheless, very few cases have been reported in the medical literature over the last century. Its pathophysiology is not completely elucidated although the unique vascularization of the scaphoid and several risk factors seem to be recurrently incriminated. Two new classifications based on modern imaging have appeared in the last decade and are now considered essential supplements to Herbert and Lanzetta's original radiographic classification. Because of the lack of formal treatment guidelines, a wide range of different treatments have been explored over time, contributing to the confusion around this pathology. Adding to this confusion, are the numerous terms used to designate the condition and lack of knowledge concerning its pathophysiology, risk factors, clinical and radiographic presentation. The aim of this review is therefore to explore and clarify Preiser's disease in terms of history, terminology, pathophysiology, clinical considerations and imaging and to propose a simple updated treatment algorithm based on the results provided by a thorough review of literature (53 publications, 170 patients) since Georg Preiser's original and controversial description in 1910.

Resistance of bone marrow mesenchymal stem cells in a stressed environment - Comparison with osteocyte cells.

Introduction: Recently, the efficacy of mesenchymal stem cells (MSCs) mediated by their tissue repair and anti-inflammatory actions in the prevention and therapy of various disorders has been reported. In this research, our attention was focused specifically on the prevention and therapy of glucocorticoid-induced osteonecrosis. We investigated the stress resistance of MSC against glucocorticoid administration and hypoxic stress, which are factors known to induce osteocytic cell death. Materials and Methods: Mouse bone cells (MLO-Y4) and bone-marrow derived mouse MSCs were exposed to dexamethasone (Dex), hypoxia of 1% oxygen or both in vitro. Mitochondrial membrane potentials were estimated by mitochondria labeling with a cell-permeant probe (Mito tracker red); expression of these apoptosis-inducing molecules, oxidative stress marker (8-hydroxy-2'-deoxyguanosine), caspase-3, -9, and two apoptosis-inhibiting molecules, energy-producing ATP synthase (ATP5A) and X-linked inhibitor of apoptosis protein (XIAP), were analyzed by both immunofluorescence and western blot. Results: With exposure to either dexamethasone or hypoxia, MLO-Y4 showed reduced mitochondrial membrane potential, ATP5A and upregulation of 8-OHdG, cleaved caspases and XIAP. Those changes were significantly enhanced by treatment with dexamethasone plus hypoxia. In MSCs, however, mitochondrial membrane potentials were preserved, while no significant changes in the pro-apoptosis or anti-apoptosis molecules analyzed were found even with exposure to both dexamethasone and hypoxia. No such effects induced by treatment with dexamethasone, hypoxia, or both were demonstrated in MSCs at all. Discussion: In osteocyte cells subjected to the double stresses of glucocorticoid administration and a hypoxic environment osteocytic cell death was mediated via mitochondria. In contrast, MSC subjected to the same stressors showed preservation of mitochondrial function and reduced oxidative stress. Accordingly, even under conditions sufficiently stressful to cause the osteocytic cell death in vivo, it was thought that the function of MSC could be preserved, suggesting that in the case of osteonecrosis preventative and therapeutic strategies incorporating their intraosseous implantation may be promising.