Osteonecrosis

MedlinePlus

Avascular necrosis; Bone infarction; Ischemic bone necrosis; AVN; Aseptic necrosis ... Osteonecrosis occurs when part of the bone does not get blood and dies. After a while, the bone can collapse. If osteonecrosis is not treated, the joint deteriorates, leading ...

Cyclosporine use and male gender are independent determinants of avascular necrosis after kidney transplantation: a cohort study.

PubMed

Schachtner, Thomas; Otto, Natalie M; Reinke, Petra

2018-06-03

Kidney transplant recipients (KTRs) are at increased risk of avascular necrosis (AVN) due to bone disorder, steroid use and common comorbidities. However, knowledge on risk factors and outcomes of AVN among KTRs in the modern era of immunosuppression remains scarce. We analysed 765 KTRs between 2001 and 2013 for AVN. Cases of symptomatic AVN were diagnosed by hip X-ray, radioisotope bone scan or magnetic resonance imaging. We evaluated risk factors and clinical characteristics of AVN. KTRs showed a constant incidence rate of AVN of 4.1% at 10 years after transplantation. The use of cyclosporine compared with tacrolimus was identified as an independent risk factor, with a rate of 8.0% compared with 2.7% at 10 years (P < 0.01). In addition, male gender was independently associated with AVN (P = 0.047). Eighty-three per cent of AVN cases were of the femoral head and treated operatively. None of the operated KTRs experienced complications in the long term. Thirty-three per cent of KTRs had bilateral AVN. Ninety-two per cent of KTRs showed AVN at the allograft side. The decreasing incidence of AVN may be attributed to the replacement of cyclosporine by tacrolimus over the last decade. Our data raise the hypothesis of an ischaemic steal syndrome due to the allograft kidney impacting AVN at the allograft side.

Neural network diagnosis of avascular necrosis from magnetic resonance images

NASA Astrophysics Data System (ADS)

Manduca, Armando; Christy, Paul S.; Ehman, Richard L.

1993-09-01

We have explored the use of artificial neural networks to diagnose avascular necrosis (AVN) of the femoral head from magnetic resonance images. We have developed multi-layer perceptron networks, trained with conjugate gradient optimization, which diagnose AVN from single sagittal images of the femoral head with 100% accuracy on the training data and 97% accuracy on test data. These networks use only the raw image as input (with minimal preprocessing to average the images down to 32 X 32 size and to scale the input data values) and learn to extract their own features for the diagnosis decision. Various experiments with these networks are described.

Prevalence and risk factor for symptomatic avascular necrosis development in Thai systemic lupus erythematosus patients.

PubMed

Kunyakham, Wichak; Foocharoen, Chingching; Mahakkanukrauh, Ajanee; Suwannaroj, Siraphop; Nanagara, Ratanavadee

2012-06-01

Avascular necrosis (AVN) has been reported in systemic lupus erythematosus (SLE) and most SLE patients suffer from this problem. To study the prevalence of AVN in Thai SLE patients and to determine the risk factors for developing AVN. A retrospective study was performed, between January 1, 1995 and August 31, 2005, on patients over 15 years of age in Khon Kaen, Thailand. The medical records of 736 SLE patients were reviewed. The female to male ratio was 15.4:1. The prevalence of AVN was 8.8%. The average age at the time of AVN detection was 27 years (range, 18-54) and the average duration of disease 69 months (range, 12-112). All cases were AVN of the hip joint. The factors correlated with AVN included: long duration of disease, history of previous septic arthritis in the ipsilateral hip to the AVN development, hematological involvement, gastrointestinal involvement, arthritis and cutaneous vasculitis. After regression analysis, hematological involvement and long duration of disease were associated with AVN with a respective odds ratio of 3.13 (95% CI 1.13-8.54) and 1.01 (95% CI 1.00-1.02). Neither high-dose steroid nor antimalarial treatment were correlated with AVN in our study and 4.6% (n = 3) of patients had never received steroid therapy during the follow-up period. Prevalence of symptomatic AVN was 8.8% in our SLE patients. A longer duration of disease and hematological involvement were associated with AVN development.

Glucocorticoid-Induced Avascular Bone Necrosis: Diagnosis and Management

PubMed Central

Chan, KL; Mok, CC

2012-01-01

Glucocorticoid use is one of the most important causes of avascular bone necrosis (AVN). The pathogenesis of glucocorticoid-induced AVN is not fully understood but postulated mechanisms include fat hypertrophy, fat emboli and intravascular coagulation that cause impedance of blood supply to the bones. Data regarding the relationship between AVN and dosage, route of administration and treatment duration of glucocorticoids are conflicting, with some studies demonstrating the cumulative dose of glucocorticoid being the most important determining factor. Early recognition of this complication is essential as the prognosis is affected by the stage of the disease. Currently, there is no consensus on whether universal screening of asymptomatic AVN should be performed for long-term glucocorticoid users. A high index of suspicion should be exhibited for bone and joint pain at typical sites. Magnetic resonance imaging (MRI) or bone scintigraphy is more sensitive than plain radiograph for diagnosing early-stage AVN. Conservative management of AVN includes rest and reduction of weight bearing. Minimization of glucocorticoid dose or a complete withdrawal of the drug should be considered if the underlying conditions allow. The efficacy of bisphosphonates in reducing the rate of collapse of femoral head in AVN is controversial. Surgical therapy of AVN includes core decompression, osteotomy, bone grafting and joint replacement. Recent advances in the treatment of AVN include the use of tantalum rod and the development of more wear resistant bearing surface in hip arthroplasty. PMID:23115605

Glucocorticoid-induced avascular bone necrosis: diagnosis and management.

PubMed

Chan, K L; Mok, C C

2012-01-01

Glucocorticoid use is one of the most important causes of avascular bone necrosis (AVN). The pathogenesis of glucocorticoid-induced AVN is not fully understood but postulated mechanisms include fat hypertrophy, fat emboli and intravascular coagulation that cause impedance of blood supply to the bones. Data regarding the relationship between AVN and dosage, route of administration and treatment duration of glucocorticoids are conflicting, with some studies demonstrating the cumulative dose of glucocorticoid being the most important determining factor. Early recognition of this complication is essential as the prognosis is affected by the stage of the disease. Currently, there is no consensus on whether universal screening of asymptomatic AVN should be performed for long-term glucocorticoid users. A high index of suspicion should be exhibited for bone and joint pain at typical sites. Magnetic resonance imaging (MRI) or bone scintigraphy is more sensitive than plain radiograph for diagnosing early-stage AVN. Conservative management of AVN includes rest and reduction of weight bearing. Minimization of glucocorticoid dose or a complete withdrawal of the drug should be considered if the underlying conditions allow. The efficacy of bisphosphonates in reducing the rate of collapse of femoral head in AVN is controversial. Surgical therapy of AVN includes core decompression, osteotomy, bone grafting and joint replacement. Recent advances in the treatment of AVN include the use of tantalum rod and the development of more wear resistant bearing surface in hip arthroplasty.

Non-corticosteroid risk factors of symptomatic avascular necrosis of bone in systemic lupus erythematosus: A retrospective case-control study.

PubMed

Faezi, Seyedeh Tahereh; Hoseinian, Azam Sadat; Paragomi, Pedram; Akbarian, Mahmood; Esfahanian, Fatemeh; Gharibdoost, Farhad; Akhlaghi, Maassoumeh; Nadji, Abdolhadi; Jamshidi, Ahmad Reza; Shahram, Farhad; Nejadhosseinian, Mohammad; Davatchi, Fereydoun

2015-07-01

Avascular necrosis of bone (AVN) is an important complication of systemic lupus erythematosus (SLE). Corticosteroid therapy has been underlined as a main risk factor for osteonecrosis. However, AVN development in patients who have never received corticosteroid and the absence of AVN in the majority of the patients, who received corticosteroid, propose a role for non-corticosteroid risk factors in AVN development. This case-control study included two subsets: oral corticosteroid (66 AVN and 248 non-AVN patients) and pulse-therapy subset (39 AVN and 312 non-AVN patients) who have attended our Lupus clinic from 1979 to 2009. Patients received similar cumulative dose corticosteroid, equal maximum dose and 1-year maximum dose of corticosteroid. The demographic data (including sex, age of disease onset, age at the diagnosis of AVN), organs involvement, SLE Disease Activity Index (SLEDAI), Systemic Lupus International Collaborating Clinics/American College of Rheumatology-Damage index (SLICC/ACR-DI), number of disease flare ups were compared between two subsets. The mean age of SLE onset was younger (P value = 0.04) in the AVN patients. In oral corticosteroid subset, malar rash (P value < 0.001) and oral ulcer (P value = 0.003) were seen more frequently in non-AVN patients, whereas psychosis (P value = 0.03) was significantly more prevalent AVN subset in oral corticosteroid subset. In corticosteroid pulse subset, no significant difference in clinical features was noted. In oral corticosteroid subset, younger age of disease onset and psychosis were significantly associated with AVN, whereas malar rash and oral ulcer showed negative association AVN.

Risk of contralateral avascular necrosis (AVN) after total hip arthroplasty (THA) for non-traumatic AVN.

PubMed

Goker, Berna; Block, Joel A

2006-01-01

The risk of developing bilateral disease progressing to total hip arthroplasty (THA) among patients who undergo unilateral THA for non-traumatic avascular necrosis (AVN) remains poorly understood. An analysis of the time-course to contralateral THA, as well as the effects of underlying AVN risk factors, is presented. Forty-seven consecutive patients who underwent THA for AVN were evaluated. Peri-operative and annual post-operative antero-posterior pelvis radiographs were examined for evidence of contralateral involvement. Patient age, weight, height, underlying AVN risk factor(s), date of onset of contralateral hip pain if occurred, and date of contralateral THA if performed, were recorded. Bone scan, computerized tomography and magnetic resonance imaging data were utilized when available. Twenty-one patients (46.6%) underwent contralateral THA for AVN within a median of 9 months after the initial THA (range 0-93, interquartile range 28.5 months). The median follow-up for patients without contralateral THA was 75 months (range 3-109, interquartile range 69 months). Thirty-four patients had radiographic findings of contralateral AVN at study entry; 25 were symptomatic bilaterally at entry and 7 developed contralateral symptoms within a mean time of 12 months (median 10 months, interquartile range 12 months). None of the 13 patients who were free of radiographic evidence of contralateral AVN at study entry developed evidence of AVN during the follow-up. AVN associated with glucocorticoid use was more likely to manifest as bilateral disease than either idiopathic AVN or ethanol-associated AVN (P=0.02 and P=0.03 respectively). Radiographically-evident AVN in the contralateral hip at THA is unlikely to remain asymptomatic for a prolonged period of time. Conversely, asymptomatic contralateral hips without radiographic evidence of AVN are unlikely to develop clinically significant AVN.

The incidence of avascular necrosis and the radiographic outcome following medial open reduction in children with developmental dysplasia of the hip: a systematic review.

PubMed

Gardner, R O E; Bradley, C S; Howard, A; Narayanan, U G; Wedge, J H; Kelley, S P

2014-02-01

The incidence of clinically significant avascular necrosis (AVN) following medial open reduction of the dislocated hip in children with developmental dysplasia of the hip (DDH) remains unknown. We performed a systematic review of the literature to identify all clinical studies reporting the results of medial open reduction surgery. A total of 14 papers reporting 734 hips met the inclusion criteria. The mean follow-up was 10.9 years (2 to 28). The rate of clinically significant AVN (types 2 to 4) was 20% (149/734). From these papers 221 hips in 174 children had sufficient information to permit more detailed analysis. The rate of AVN increased with the length of follow-up to 24% at skeletal maturity, with type 2 AVN predominating in hips after five years' follow-up. The presence of AVN resulted in a higher incidence of an unsatisfactory outcome at skeletal maturity (55% vs 20% in hips with no AVN; p < 0.001). A higher rate of AVN was identified when surgery was performed in children aged < 12 months, and when hips were immobilised in ≥ 60° of abduction post-operatively. Multivariate analysis showed that younger age at operation, need for further surgery and post-operative hip abduction of ≥ 60° increased the risk of the development of clinically significant AVN.

Analysis of Arthroscopic Therapy for hip Pathologies.

PubMed

Przybył, Michał; Walenczak, Krzysztof; Lebiedziński, Radosław; Domżalski, Marcin

2017-05-10

[b]Background. [/b]This paper analyses the outcomes of treatment of avascular necrosis (AVN), femoroacetabular impingement (FAI), hip labral tear (HLT) and snapping hip syndrome (SHS). Moreover, the results of individual groups are also compared. The study group consisted of 70 persons (surgeries of 72 hips). AVN - 14 patients, FAI - 38 patients (39 hips), HLT - 12 patients (13 hips), SHS - 6 patients. Two questionnaires, namely the MHHS (Modified Harris Hip Score) and NAHS (Non Arthritic Hip Score), were used to evaluate the patients before the surgery and at 6- and 12-month follow-up.[b]Results. [/b]AVN : local improvement was recorded at both 6 and 12 months, FAI: local improvement was recorded at both 6 and 12 months, HLT: local improvement was recorded at both 6 and 12 months, SHS: local improvement was recorded at both 6 and 12 months. Comparison of the results between the groups showed that: At baseline, local status in AVN was poorer than in FAI. At 6- and 12-month follow-up, local status in AVN was poorer than in FAI, HLT and SHS.[b]Conclusions.[/b] AVN Group 1. The study demonstrates that arthroscopic treatment of avascular necrosis produced fairly good outcomes at 6 and 12 months after the surgery. 2. Treatment of avascular necrosis showed significantly poorer results than therapy of femoroacetabular impingement, hip labral tear and snapping hip syndrome at 6 and 12 months. FAI Group 1. Arthroscopic treatment of femoroacetabular impingement produced good outcomes at 6 and 12 months after the surgery. HLT Group 1. Arthroscopic treatment of hip labral tear produced excellent outcomes at 6 and 12 months after the surgery. SHS Group 1. Arthroscopic treat ment of snapping hip syndrome produced excellent outcomes at 6 and 12 months after the surgery.Additional conclusions. 1. Studies showing long-term effect of arthroscopic treatment of selected conditions are necessary to further assess the effectiveness of this treatment. 2. It is necessary to evaluate the influence of the patients' age and severity of osteo arthritis on treatment outcomes in FAI. 3. It is necessary to assess the influence of the severity of pre-operative necrosis according to Ficat and Arlet classification on treatment outcomes in AVN.

Risk Factors for Symptomatic Avascular Necrosis in Childhood-onset Systemic Lupus Erythematosus.

PubMed

Yang, Yelin; Kumar, Sathish; Lim, Lily Siok Hoon; Silverman, Earl D; Levy, Deborah M

2015-12-01

To examine the frequency and risk factors for symptomatic avascular necrosis (AVN) in childhood-onset systemic lupus erythematosus (cSLE). A single-center, nested, matched, case-control design was used. There were 617 patients with cSLE followed at the Hospital for Sick Children (SickKids) Lupus Clinic between July 1982 and June 2013 included in the study. The AVN cohort consisted of 37 patients identified with clinical findings of symptomatic AVN and diagnosis was confirmed by 1 or more imaging modalities. Three controls were matched to each patient with AVN by date and age at diagnosis. Baseline clinical, laboratory, and treatment characteristics were compared between patients with AVN and controls by univariable analyses and if statistically significant, were included in a multivariable logistic regression model. A total of 37/617 patients (6%) developed symptomatic AVN in 91 joints during followup at SickKids. The mean duration to disease was 2.3 years. The hip was the most commonly involved joint (26/37, 70%). Compared with the matched non-AVN cohort, patients with AVN had a higher incidence of central nervous system (CNS) involvement and nephritis, required greater cumulative prednisone (PRED) from cSLE diagnosis to AVN, received a greater maximal daily PRED dose, and had more frequent use of pulse methylprednisolone therapy. Multivariable regression analysis confirmed major organ involvement (CNS disease and/or nephritis) and maximal daily PRED dose as significant predictors of symptomatic AVN development. Patients with cSLE with severe organ involvement including nephritis and CNS disease and higher maximal daily dose of PRED are more likely to develop symptomatic AVN.

A meta-analysis of avascular necrosis in systemic lupus erythematosus: prevalence and risk factors.

PubMed

Nevskaya, Tatiana; Gamble, Maeve P; Pope, Janet E

2017-01-01

To determine the prevalence of and risk factors for avascular necrosis (AVN) in systemic lupus erythematosus (SLE). MEDLINE, CINAHL, Web of Science, EMBASE and Cochrane Library were searched from inception to July, 2015 and a random effects model was used to combine frequencies; study quality was assessed using STROBE. 2,041 citations identified 62 articles. Many results had high heterogeneity. The prevalence of symptomatic AVN was 9% (range 0.8%-33%) in SLE and 29% for asymptomatic AVN; femoral head was the most common location (8.0%). High-dose corticosteroids (CS) any CS use, maximum and cumulative dose, pulse therapy, and CS side-effects (hypertension, Cushings, but not diabetes mellitus or hyperlipidaemia) were associated with AVN, as was active SLE (cutaneous vasculitis, renal and neuropsychiatric manifestations, serositis, cytopenias) and Sjögren's, Raynaud's phenomenon, arthritis, cyclophosphamide (but not azathioprine mycophenolate mofetil, or methotrexate) and more damage (excluding musculoskeletal system). Antimalarial drugs were not protective. Rashes and oral ulcers were not associated with AVN. Mean daily dose of CS and duration of CS use had no impact on AVN occurence. Autoantibodies and other immunological markers did not predispose to AVN, except IgM anticardiolipin antibodies which doubled the risk. African Americans experienced more AVN (OR 1.8, p=0.04). AVN may occur in 1/3 of patients with SLE and 9% with symptoms. Features of active organ SLE (CNS, renal, cutaneous vasculitis, serositis, cytopenias) are associated with AVN as are CS, especially early in disease and at high doses. Those with early CS side-effects seem to have the highest risk of AVN.

Femoral head avascular necrosis: a frequently missed incidental finding on multidetector CT.

PubMed

Barille, M F; Wu, Jim S; McMahon, Colm J

2014-03-01

To determine the incidence of missed femoral head avascular necrosis (AVN) on pelvic computed tomography (CT) performed for clinical indications other than assessment for AVN. The study was a Health Insurance Portability and Accountability Act (HIPAA)-compliant retrospective study. The picture archiving and communication system (PACS) database was queried for patients with diagnosis of femoral head AVN on magnetic resonance imaging (MRI), who also underwent pelvic multidetector CT after or <30 days before the MRI examination. The MRI and CT images of 144 hips of 72 patients (39 patients with reported AVN on MRI and 33 age-matched controls; mean age = 60 years, 28 male, 44 female), were reviewed in consensus by two readers in a randomized, blinded manner. Using MRI-proven CT-visible AVN as a reference standard, the incidence of missed AVN on initial CT interpretation was determined. Readers confirmed AVN in 33 patients on the MRI images. Nine hips with AVN underwent joint replacement of the affected joint(s) prior to subsequent CT and were excluded. Forty-three MRI-proven AVN cases in 28 patients (15 bilateral, 13 unilateral) were available for analysis. The study readers diagnosed 35/43 (81%) MRI-proven AVN cases in 22/28 (79%) patients. Four of the 35 (11%) cases of MRI-proven, CT-visible AVN were prospectively reported in 3/22 (14%) patients at initial clinical interpretation, with a miss rate of 89% per hip and 86% per patient. Multidetector CT has high accuracy for detection of AVN; however, this is frequently missed as an incidental finding (89% missed in the present study). Assessment for signs of femoral AVN should be part of routine search pattern in interpretation of pelvic CT. Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Bilateral femoral head avascular necrosis with a very low dose of oral corticosteroid used for panhypopituitarism

PubMed Central

Dharmshaktu, Pramila; Aggarwal, Anshita; Dutta, Deep; Kulshreshtha, Bindu

2016-01-01

Avascular necrosis (AVN) of the femoral head is a rare complication related to glucocorticoid administration and traditionally has been associated with high doses and/or prolonged therapy. Occurrence of osteonecrosis with a physiological replacement dose of glucocorticoids has not been reported previously. We report a 38-year-old man with non-secreting pituitary adenoma who developed bilateral AVN while on a very small dose of oral prednisolone for secondary adrenal insufficiency after surgery for pituitary adenoma. The patient was switched to hydrocortisone. Zolindronic acid was administered and the patient underwent bilateral core decompressive surgery resulting in a reduction of hip pain and improvement. When last evaluated, 2 years after diagnosis of AVN, the patient was functionally independent, and was able to do his routine activities with mild pain. The report intends to highlight the occurrence of AVN of the femur even with a very small dose of prednisolone used for treatment of panhypopituitarism. Glucocorticoids may have to be continued in the lowest possible dose using the most physiological preparation such as hydrocortisone when stoppage is not possible. PMID:26762348

Bilateral femoral head avascular necrosis with a very low dose of oral corticosteroid used for panhypopituitarism.

PubMed

Dharmshaktu, Pramila; Aggarwal, Anshita; Dutta, Deep; Kulshreshtha, Bindu

2016-01-13

Avascular necrosis (AVN) of the femoral head is a rare complication related to glucocorticoid administration and traditionally has been associated with high doses and/or prolonged therapy. Occurrence of osteonecrosis with a physiological replacement dose of glucocorticoids has not been reported previously. We report a 38-year-old man with non-secreting pituitary adenoma who developed bilateral AVN while on a very small dose of oral prednisolone for secondary adrenal insufficiency after surgery for pituitary adenoma. The patient was switched to hydrocortisone. Zolindronic acid was administered and the patient underwent bilateral core decompressive surgery resulting in a reduction of hip pain and improvement. When last evaluated, 2 years after diagnosis of AVN, the patient was functionally independent, and was able to do his routine activities with mild pain. The report intends to highlight the occurrence of AVN of the femur even with a very small dose of prednisolone used for treatment of panhypopituitarism. Glucocorticoids may have to be continued in the lowest possible dose using the most physiological preparation such as hydrocortisone when stoppage is not possible. 2016 BMJ Publishing Group Ltd.

Temporal course of avascular femoral head necrosis in patients with pemphigus vulgaris.

PubMed

Balighi, Kamran; Daneshpazhooh, Maryam; Aghazadeh, Nessa; Saeidi, Vahide; Shahpouri, Farzam; Hejazi, Pardis; Chams-Davatchi, Cheyda

2016-10-01

Pemphigus vulgaris (PV) is typically treated with systemic corticosteroids and immunosuppressive agents. Avascular necrosis (AVN) of the femoral head is a well-recognized major complication of corticosteroid therapy. The characteristics of this serious complication in PV remain unknown. Uncontrolled, retrospective study of all PV-related AVN cases diagnosed at an Iranian autoimmune bullous disease clinic between 1985 and 2013. Of the 2,321 medical records of PV patients reviewed, 45 (1.93 %) cases showed femoral AVN, with 30 (66.7 %) individuals being male. The mean age at diagnosis of AVN was 47.4 ± 14.2 years. The mean interval between the diagnosis of PV and the onset of AVN was 25.3 ± 18.3 months. With the exception of eight cases (17.8 %), the majority of patients developed AVN within three years after the diagnosis of PV. The mean cumulative dose of prednisolone in patients with AVN was 13,115.8 ± 7041.1 mg. There was a strong correlation between the total prednisolone dose and the time of onset of AVN (p = 0.001). In patients with a history of alendronate intake, that interval was significantly shorter (p = 0.01). Occurring in about 2 % of patients, AVN is a serious complication of corticosteroid treatment in patients with PV, predominantly in the first three years of treatment. In individuals receiving higher doses of prednisolone, AVN tends to occur earlier. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Associations Between Antiretroviral Treatment and Avascular Bone Necrosis: The Swiss HIV Cohort Study.

PubMed

Bayard, Cornelia; Ledergerber, Bruno; Flepp, Markus; Lecompte, Thanh; Moulin, Estelle; Hoffmann, Matthias; Weber, Rainer; Staehelin, Cornelia; Di Benedetto, Caroline; Fux, Christoph A; Tarr, Philip E; Hasse, Barbara

2017-01-01

HIV-infected individuals have an increased risk of avascular bone necrosis (AVN). Antiretroviral therapy (ART) and particularly protease inhibitors (PI) have been implicated as a risk factor. We aimed to study the associations of ART with the occurrence of AVN among Swiss HIV Cohort Study participants (SHCS). We used incidence density sampling to perform a case control study within the Swiss HIV Cohort Study (SHCS) comparing prospectively collected AVN cases and controls by conditional logistic regression analysis. To evaluate the effect of ART, multivariable models were adjusted for HIV transmission risk group, age, alcohol consumption, use of corticosteroids, CD4 nadir, maximum viral load, and pancreatitis. We compared 74 AVN cases and 145 controls. Associations with AVN were shown for heterosexual HIV acquisition (odds ratio [OR], 3.4; 95% confidence interval [CI], 1.1-10), alcohol consumption (OR, 2.7; 95% CI, 1.3-5.7), and hyperlipidemia (OR, 3.6; 95% CI, 1.4-9.6). After adding ART substances to the multivariable base model, there was evidence of an association for treatment with tenofovir (TDF) >1 year (OR, 4.4; 95% CI, 1.4-14) with AVN. Neither exposure to specific frequently prescribed ART combinations or ART drug classes nor cumulative ART exposure showed any associations with AVN. In the HIV-infected population, a combination of risk factors such as heterosexual HIV acquisition, moderate to severe alcohol intake, and hyperlipidemia seem to contribute to AVN. ART does not seem to be a relevant risk factor for AVN. The association of prolonged TDF exposure with AVN needs to be confirmed.

Prevalence and Associations of Avascular Necrosis of the Hip in a Large Well-characterized Cohort of Patients With Inflammatory Bowel Disease.

PubMed

Rolston, Vineet S; Patel, Anish V; Learch, Thomas J; Li, Dalin; Karayev, Dmitry; Williams, Chadwick; Siddanthi, Madhavi L; Targan, Stephan R; Weisman, Michael H; McGovern, Dermot P B

2018-05-24

Avascular necrosis (AVN) is associated with significant morbidity potentially causing severe pain and debility; patients with inflammatory bowel disease (IBD) have a higher prevalence of AVN compared with non-IBD populations. The purpose of our study was to determine the prevalence of AVN in our IBD population and to evaluate these subjects for the presence of clinical characteristics associated with AVN on computed tomography (CT) imaging. In 1313 IBD patients with abdomen/pelvis CT scans, we identified 27 patients (2.1%) with CT findings consistent with AVN. Through historical chart review, we confirmed that most patients had prior exposure to steroids, although 2 patients had no documented steroid exposure at all. We found that 59% of the concurrent radiology reports did not comment on the presence of AVN, suggesting that incidental CT findings of AVN among IBD patients are likely underreported. Notably, we found that 63% of these cases had documented complaints of low-back and/or hip pain. Using logistic regression, we found an association between anti-neutrophil cytoplasmic antibody-positive status across IBD (P = 0.007) and a smoking history in Crohn disease (P = 0.03) with the presence of AVN. We found that a significant proportion of IBD patients with AVN are reported in their records as not having hip or low-back pain, and review of CT imaging under dedicated bone windows may identify AVN among this population. Our findings also suggest that additional etiological factors, beyond corticosteroids, contribute to the development of AVN in IBD. Further investigation is warranted regarding the mechanisms associated with AVN in IBD.

Avascular necrosis as a complication of the treatment of dislocation of the hip in children with cerebral palsy.

PubMed

Koch, A; Jozwiak, M; Idzior, M; Molinska-Glura, M; Szulc, A

2015-02-01

We investigated the incidence and risk factors for the development of avascular necrosis (AVN) of the femoral head in the course of treatment of children with cerebral palsy (CP) and dislocation of the hip. All underwent open reduction, proximal femoral and Dega pelvic osteotomy. The inclusion criteria were: a predominantly spastic form of CP, dislocation of the hip (migration percentage, MP > 80%), Gross Motor Function Classification System, (GMFCS) grade IV to V, a primary surgical procedure and follow-up of > one year. There were 81 consecutive children (40 girls and 41 boys) in the study. Their mean age was nine years (3.5 to 13.8) and mean follow-up was 5.5 years (1.6 to 15.1). Radiological evaluation included measurement of the MP, the acetabular index (AI), the epiphyseal shaft angle (ESA) and the pelvic femoral angle (PFA). The presence and grade of AVN were assessed radiologically according to the Kruczynski classification. Signs of AVN (grades I to V) were seen in 79 hips (68.7%). A total of 23 hips (18%) were classified between grades III and V. Although open reduction of the hip combined with femoral and Dega osteotomy is an effective form of treatment for children with CP and dislocation of the hip, there were signs of avascular necrosis in about two-thirds of the children. There was a strong correlation between post-operative pain and the severity of the grade of AVN. ©2015 The British Editorial Society of Bone & Joint Surgery.

Avascular Necrosis of Trochlea After Supracondylar Humerus Fractures in Children.

PubMed

Etier, Brian E; Doyle, J Scott; Gilbert, Shawn R

2015-10-01

Avascular necrosis (AVN) is a rare but important complication after supracondylar humerus fractures. Posttraumatic humerus deformity was first reported in 1948 and sporadically thereafter. AVN deformity has been classified as type A (AVN of the lateral ossification center) and type B (AVN of the entire medial crista and a metaphyseal portion). In this article, we present 5 cases of AVN after supracondylar humerus fracture, discuss the importance of late clinical findings, and postulate a mechanism of AVN in nondisplaced fractures. Five cases of AVN after supracondylar humerus fracture were reviewed from the Children's of Alabama database. Four of the 5 patients were female. Four patients sustained a Gartland type III fracture, and 1 patient sustained a nondisplaced Gartland type I fracture. Age at time of injury ranged from 5 years to 10 years. All patients had an asymptomatic clinical period after treatment and re-presented 6 months to 7 years later with elbow pain or loss of motion. All patients were treated symptomatically. AVN of the trochlea has a late clinical presentation. The cause of this complication is interruption of the trochlea blood supply. In displaced fractures, the medial and/or lateral vessels are injured, leading to type A or type B deformity. In nondisplaced fractures, the lateral vessels are interrupted by tamponade because of encased fracture hematoma; this presents as a type A deformity. Both type A and type B deformities can be clinically significant. AVN of the trochlea should be considered in patients with late presentation of pain or loss of motion after treatment of supracondylar humerus fractures.

Expression of osteoprotegerin, RNAK and RANKL genes in femoral head avascular necrosis and related signaling pathway.

PubMed

Miao, Qingtang; Hao, Sibin; Li, Hongmei; Sun, Fang; Wang, Xueling

2015-01-01

Femoral head avascular necrosis (AVN) causes the damage of hip joint and related dysfunctions, thus consisting of a clinical challenge. Osteoprotegerin (OPG), receptor activator of nuclear factor κB (RANK) and its ligand (RANKL) all regulate the formation of bones via gene transcriptional regulation for the balance between osteoblasts and osteoclasts. This study thus investigated the expressional profiles of OPG, RANK and RANKL genes in AVN patients, and explored related molecular mediating pathways. Real-time qPCR was used to measure the gene expression of OPG, RANK and RANKL genes in AVN femoral head tissue samples from 42 patients, along with normal tissues. Western blotting analysis was performed to quantify protein levels of OPG and RANKL. There was a trend but not statistically significant elevation of mRNA levels of OPG in femoral head AVN tissues compared to normal tissues (P>0.05). The expression of RNAK and RNAKL, however, was significantly elevated in necrotic tissues (P<0.05). No significant difference in protein levels of OPG or RANKL between groups. The expression of OPG, RANK and RANKL genes exert a crucial role in the progression of AVN, suggesting their roles in mediating bone homeostasis and potential effects on bone destruction.

Increased risk of avascular necrosis in patients with psoriatic disease: A nationwide population-based matched cohort study.

PubMed

Chiu, Hsien-Yi; Wang, I-Ting; Huang, Weng-Foung; Tsai, Yi-Wen; Shiu, Ming-Neng; Tsai, Tsen-Fang

2017-05-01

Avascular necrosis (AVN) and psoriasis have some pathogenic mechanisms and associated conditions in common. To examine the association between psoriasis and AVN. This study used data from the Taiwan National Health Insurance Research Database for the period 2004-2006 and identified 28,268 patients with psoriasis, who were then matched for age and sex with 113,072 controls without psoriasis from the Taiwan Longitudinal Health Insurance Database 2000. Multivariate Cox proportional hazards models were used for the analysis. The unadjusted risk of AVN was significantly higher for patients with psoriasis than for controls (hazard ratio [HR] 2.29) and remained significant after adjustment for other risk factors (adjusted HR 1.96; 95% confidence interval 1.62-2.38). The risk for AVN increased in relation to psoriasis severity and was higher for patients with psoriasis and arthritis than for patients without arthritis. The adjusted HRs were higher for male patients than for female patients and for patients younger than 30 years compared with older patients. We lacked information on daily tobacco use, alcohol consumption, and physical activity. The risk for AVN increased with the disease severity of psoriasis. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Avascular necrosis of bone following allogeneic hematopoietic cell transplantation in children and adolescents

PubMed Central

Li, Xiaxin; Brazauskas, Ruta; Wang, Zhiwei; Al-Seraihy, Amal; Baker, K. Scott; Cahn, Jean-Yves; Frangoul, Haydar A.; Gajewski, James L.; Hale, Gregory A.; Hsu, Jack W.; Kamble, Rammurti T.; Lazarus, Hillard M.; Marks, David I.; Maziarz, Richard T.; Savani, Bipin N.; Shah, Ami J.; Shah, Nirali; Sorror, Mohamed L.; Wood, William A.; Majhail, Navneet S.

2014-01-01

We conducted a nested case-control study within a cohort of 6,244 patients to assess risk factors for avascular necrosis (AVN) of bone in children and adolescents following allogeneic transplantation. Eligible patients were ≤21 years of age, received their first allogeneic transplant between 1990 and 2008 in the United States and had survived ≥ 6 months from transplantation. Overall, 160 cases with AVN and 478 controls matched by year of transplant, length of followup and transplant center were identified. Cases and controls were confirmed via central review of radiology, pathology and/or surgical procedure reports. Median time from transplant to diagnosis of AVN was 14 months. On conditional logistic regression, increasing age at transplant (≥5 years), female gender and chronic graft-versus-host disease (GVHD) were significantly associated with increased risks of AVN. Compared to patients receiving myeloablative regimens for malignant diseases, lower risks of AVN were seen in patients with non-malignant diseases and those who had received reduced intensity conditioning regimens for malignant diseases. Children at high risk for AVN include those within the age group where rapid bone growth occurs as well as those who experience exposure to myeloablative conditioning regimens and immunosuppression post-HCT for the treatment of GVHD. More research is needed to determine whether screening strategies specifically for patients at high risk for developing AVN with early interventions may mitigate the morbidity associated with this complication. PMID:24388803

Associations Between Antiretroviral Treatment and Avascular Bone Necrosis: The Swiss HIV Cohort Study

PubMed Central

Bayard, Cornelia; Ledergerber, Bruno; Flepp, Markus; Lecompte, Thanh; Moulin, Estelle; Hoffmann, Matthias; Weber, Rainer; Staehelin, Cornelia; Di Benedetto, Caroline; Fux, Christoph A; Tarr, Philip E; Aubert, V; Battegay, M; Bernasconi, E; Böni, J; Braun, DL; Bucher, HC; Calmy, A; Cavassini, M; Ciuffi, A; Dollenmaier, G; Egger, M; Elzi, L; Fehr, J; Fellay, J; Furrer, H; Fux, CA; Günthard, HF; Haerry, D; Hasse, B; Hirsch, HH; Hoffmann, M; Hösli, I; Kahlert, C; Kaiser, L; Keiser, O; Klimkait, T; Kouyos, RD; Kovari, H; Ledergerber, B; Martinetti, G; Martinez de Tejada, B; Marzolini, C; Metzner, KJ; Müller, N; Nicca, D; Pantaleo, G; Paioni, P; Rauch, A; Rudin, C; Scherrer, AU; Schmid, P; Speck, R; Stöckle, M; Tarr, P; Trkola, A; Vernazza, P; Wandeler, G; Weber, R; Yerly, S

2017-01-01

Abstract Background HIV-infected individuals have an increased risk of avascular bone necrosis (AVN). Antiretroviral therapy (ART) and particularly protease inhibitors (PI) have been implicated as a risk factor. We aimed to study the associations of ART with the occurrence of AVN among Swiss HIV Cohort Study participants (SHCS). Methods We used incidence density sampling to perform a case control study within the Swiss HIV Cohort Study (SHCS) comparing prospectively collected AVN cases and controls by conditional logistic regression analysis. To evaluate the effect of ART, multivariable models were adjusted for HIV transmission risk group, age, alcohol consumption, use of corticosteroids, CD4 nadir, maximum viral load, and pancreatitis. Results We compared 74 AVN cases and 145 controls. Associations with AVN were shown for heterosexual HIV acquisition (odds ratio [OR], 3.4; 95% confidence interval [CI], 1.1–10), alcohol consumption (OR, 2.7; 95% CI, 1.3–5.7), and hyperlipidemia (OR, 3.6; 95% CI, 1.4–9.6). After adding ART substances to the multivariable base model, there was evidence of an association for treatment with tenofovir (TDF) >1 year (OR, 4.4; 95% CI, 1.4–14) with AVN. Neither exposure to specific frequently prescribed ART combinations or ART drug classes nor cumulative ART exposure showed any associations with AVN. Conclusions In the HIV-infected population, a combination of risk factors such as heterosexual HIV acquisition, moderate to severe alcohol intake, and hyperlipidemia seem to contribute to AVN. ART does not seem to be a relevant risk factor for AVN. The association of prolonged TDF exposure with AVN needs to be confirmed. PMID:29026869

National trends and in hospital outcomes for total hip arthroplasty in avascular necrosis in the United States.

PubMed

Mayers, William; Schwartz, Brian; Schwartz, Aaron; Moretti, Vincent; Goldstein, Wayne; Shah, Ritesh

2016-09-01

While a majority of total hip arthroplasty (THA) is performed for osteoarthritis (OA), a significant portion is performed in the setting of avascular necrosis (AVN). The purpose of this study is to evaluate recent trends, patient demographics, and in hospital outcomes for primary THA in the setting of AVN in the United States. The National Hospital Discharge Survey database was searched for patients admitted to US hospitals after a primary THA for the years 2001-2010. Patients were then separated into two groups by ICD-9 diagnosis codes for OA and AVN. The rates of THA for AVN (r = 0.65) and THA for OA (r = 0.82) both demonstrated a positive correlation with time. The mean patient age of the AVN group was significantly lower (56.9 vs 65.9 years, p < 0.01). Men accounted for 51.9 % of the AVN group and 43.0 % of the OA group (p < 0.01). The AVN group had a significantly higher percentage of African Americans (11.2 % vs 5.4 %, p < 0.01) when compared to the OA group. The AVN group had a higher rate of myocardial infarction (0.3 % vs 0.07 %, p = 0.0163) and a higher average number of medical co-morbidities (5.16 vs 4.77, p < 0.01). Patients undergoing THA for AVN were more likely to be younger, male, African American, have more medical co-morbidities, and more likely to have a myocardial infarction than those with OA. While the number of primary THAs performed for AVN in the United States has increased over the past ten years, the rate of primary THA for OA increased at a much more rapid rate.

Avascular necrosis of femoral and/or humeral heads in multiple myeloma: results of a prospective study of patients treated with dexamethasone-based regimens and high-dose chemotherapy.

PubMed

Talamo, Giampaolo; Angtuaco, Edgardo; Walker, Ronald C; Dong, Li; Miceli, Marisa H; Zangari, Maurizio; Tricot, Guido; Barlogie, Bart; Anaissie, Elias

2005-08-01

To assess the prevalence, time of onset, risk factors, and outcome of avascular necrosis (AVN) of bone in patients with multiple myeloma undergoing antineoplastic therapy. A total of 553 consecutive assessable patients were enrolled onto a treatment protocol consisting of dexamethasone-containing induction chemotherapy, autologous stem-cell transplantation, consolidation chemotherapy, and maintenance with interferon alfa. Patients were randomly assigned to receive thalidomide (269 patients) or no thalidomide (284 patients) throughout the study period. With a median follow-up of 33 months (range, 5 to 114 months), AVN of the femoral head(s) developed in 49 patients (9%). Median time to onset of AVN was 12 months (range, 2 to 41 months). Three risk factors for AVN were identified by multivariate analysis: cumulative dexamethasone dose (odds ratio [OR], 1.028; 95% CI, 1.012 to 1.044; P = .0006 [per 40 mg dexamethasone]), male sex (OR, 0.390; 95% CI, 0.192 to 0.790; P = .009), and younger age (OR, 0.961; 95% CI, 0.934 to 0.991 per year; P = .0122). Thalidomide-treated patients had a prevalence of AVN similar to that of the control group (8% v 10%, respectively; P = .58). AVN-related pain and limited range of motion of the affected joint were present in only nine and four patients, respectively, and four patients underwent hip replacement because of AVN. Fluorine-18 fluorodeoxyglucose positron emission tomography failed to detect abnormal uptake in the AVN-affected bones. AVN is a rare and usually asymptomatic complication during myeloma therapy. Cumulative dexamethasone dose, male sex, and younger age, but not thalidomide, increase the risk of AVN.

Complete resolution of avascular necrosis of the human femoral head treated with adipose tissue-derived stem cells and platelet-rich plasma.

PubMed

Pak, Jaewoo; Lee, Jung Hun; Jeon, Jeong Ho; Lee, Sang Hee

2014-12-01

We report a case of a 43-year-old man with early stage (stage 1) avascular necrosis (AVN) of the femoral head treated with adipose tissue-derived stem cells (ASCs) and platelet-rich plasma (PRP). ASC-containing stromal vascular fraction was mixed with PRP and hyaluronic acid. This mixture was then injected into the diseased hip under ultrasound guidance. The affected hip was reinjected weekly with additional PRP for 4 weeks. The patient was followed-up with sequential magnetic resonance imaging (MRI) scans at 3, 18, and 21 months after treatment, together with Visual Analogue Scale (VAS) Walking Index, Functional Rating Index, Harris Hip Score, and Range of Motion (ROM) assessments. The patient's severe hip pain was considerably improved at 3 months after treatment, with pain scores, ROM and MRI showing near complete resolution of AVN. Pain scores, ROM and MRI at 18 and 21 months after treatment indicated complete resolution of AVN. This case represents the first evidence of complete resolution of early stage AVN of the hip following treatment with ASCs/PRP. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Timing of initiation of enzyme replacement therapy after diagnosis of type 1 Gaucher disease: effect on incidence of avascular necrosis

PubMed Central

Mistry, Pramod K; Deegan, Patrick; Vellodi, Ashok; Cole, J Alexander; Yeh, Michael; Weinreb, Neal J

2009-01-01

Data from the International Collaborative Gaucher Group Gaucher Registry were analysed to assess the relationship between enzyme replacement therapy with imiglucerase (ERT) and incidence of avascular necrosis (AVN) in type 1 Gaucher disease (GD1), and to determine whether the time interval between diagnosis and initiation of ERT influences the incidence rate of AVN. All patients with GD1 enrolled in the Gaucher Registry who received ERT and did not report AVN prior to starting therapy (n = 2700) were included. The incidence rate of AVN following initiation of ERT was determined. An incidence rate of AVN of 13·8 per 1000 person-years was observed in patients receiving ERT. Patients who initiated ERT within 2 years of diagnosis had an incidence rate of 8·1 per 1000 person-years; patients who started ERT ≥2 years after diagnosis had an incidence rate of 16·6 per 1000 person-years. The adjusted incidence rate ratio was 0·59 [95% confidence interval (CI) 0·36–0·96, P = 0·0343]. Splenectomy was an independent risk factor for AVN (adjusted incidence rate ratio 2·23, 95% CI 1·61–3·08, P < 0·0001). In conclusion, the risk of AVN was reduced among patients who initiated ERT within 2 years of diagnosis, compared to initiating treatment ≥2 years after diagnosis. A higher risk of AVN was observed among patients who had previously undergone splenectomy. PMID:19732054

Systematic Review and Meta-Analysis of Avascular Necrosis and Posttraumatic Arthritis After Traumatic Hip Dislocation.

PubMed

Kellam, Patrick; Ostrum, Robert F

2016-01-01

To determine the incidence rate and associative factors for the development of avascular necrosis (AVN) and posttraumatic arthritis (PTA) after traumatic hip dislocation and time to reduction. A comprehensive search of databases including PubMed, Cochrane Database, and Embase through April 2014 for English articles reporting complications of AVN and PTA after hip dislocation was performed. Inclusion criteria were English-only studies, a patient population of adults, study outcomes of AVN and/or PTA reported, and articles reported at least type I dislocations. Two authors independently extracted data from the selected studies and the data collected were compared to verify agreement. Random-effects models were used for meta-analysis. The overall event rate of AVN and PTA was calculated and stratified based on Thompson-Epstein of the hip dislocation. Odds ratios were calculated for those articles that reported rates of AVN based on time to reduction. For anterior dislocations, the event rate for AVN ranged from 0.087 to 0.333, whereas the event rate for PTA ranged from 0.125 to 0.700. Analysis of posterior dislocations revealed that the event rate for AVN ranged from 0.106 to 0.430; additionally, the event rate for PTA ranged from 0.194 to 0.586. For posterior hip dislocations and type I and II anterior dislocations, the severity of the injury correlates with an increase in the development of AVN and PTA. The odds ratio of AVN for those hip dislocations reduced after 12 hours versus those reduced before 12 hours was 5.627. Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Failed Pavlik harness treatment for DDH as a risk factor for avascular necrosis.

PubMed

Tiruveedhula, Madhu; Reading, Isabel C; Clarke, Nicholas M P

2015-03-01

Avascular necrosis (AVN) of the femoral head is an irreversible complication seen in the treatment of developmental dysplasia of hip (DDH) with the Pavlik harness. Its incidence is reported to be low after successful reduction of the hip but high if the hip is not concentrically relocated. We aim to investigate its incidence after failed Pavlik harness treatment. We prospectively followed up a group of children who failed Pavlik harness treatment for DDH treated at our institution by the senior author between 1988 and 2001 and compared their rates of AVN with a group of children who presented late and hence were treated surgically. AVN was graded as described by Kalamchi and MacEwen and only grade 2 to 4 AVN was considered significant and included in the analysis. Thirty-seven hips were included in the failed Pavlik group (group 1) and 86 hips in the no Pavlik group (group 2). Ten hips in group 1 developed AVN (27%), whereas only 7 hips in group 2 (8%) developed AVN; the odds of developing AVN after failed Pavlik treatment was 4.7 (95% confidence interval, 1.3-14.1) (P=0.009) with a relative risk of 3.32 (range, 1.37 to 8.05). There was no statistically significant association observed with duration of splintage and severity of AVN (Spearman's correlation, -0.46; P=0.18). However, there was a positive correlation noted with age at presentation and severity of AVN. Therefore, we advise close monitoring of hips in the Pavlik harness and discontinue its use if the hips are not reduced within 3 weeks. Level III.

Risk Stratification for Avascular Necrosis of the Femoral Head After Internal Fixation of Femoral Neck Fractures by Post-Operative Bone SPECT/CT.

PubMed

Han, Sangwon; Oh, Minyoung; Yoon, Seokho; Kim, Jinsoo; Kim, Ji-Wan; Chang, Jae-Suk; Ryu, Jin-Sook

2017-03-01

Avascular necrosis (AVN) of the femoral head is a major complication after internal fixation of a femoral neck fracture and determines the functional prognosis. We investigated postoperative bone single-photon emission computed tomography/computed tomography (SPECT/CT) for assessing the risk of femoral head AVN. We retrospectively reviewed 53 consecutive patients who underwent bone SPECT/CT within 2 weeks of internal fixation of a femoral neck fracture and follow-up serial hip radiographs over at least 12 months. Nine patients developed femoral head AVN. In 15 patients who showed normal uptake on immediate postoperative SPECT/CT, no AVN occurred, whereas 9 of 38 patients who showed cold defects of the femoral head later developed AVN. The negative predictive value of immediate postoperative SPECT/CT for AVN was 100 %, whereas the positive predictive value was 24 %. Among 38 patients with cold defects, 1 developed AVN 3 months postoperatively. A follow-up bone SPECT/CT was performed in the other 37 patients at 2-10 months postoperatively. The follow-up bone SPECT/CT revealed completely normalized femoral head uptake in 27, partially normalized uptake in 8, and persistent cold defects in 2 patients. AVN developed in 3.7 % (1/27), 62.5 % (5/8), and 100 % (2/2) of each group, respectively. According to the time point of imaging, radiotracer uptake patterns of the femoral head on postoperative bone SPECT/CT indicate the risk of AVN after internal fixation of femoral neck fractures differently. Postoperative bone SPECT/CT may help orthopedic surgeons determine the appropriate follow-up of these patients.

Engineered, axially-vascularized osteogenic grafts from human adipose-derived cells to treat avascular necrosis of bone in a rat model.

PubMed

Ismail, Tarek; Osinga, Rik; Todorov, Atanas; Haumer, Alexander; Tchang, Laurent A; Epple, Christian; Allafi, Nima; Menzi, Nadia; Largo, René D; Kaempfen, Alexandre; Martin, Ivan; Schaefer, Dirk J; Scherberich, Arnaud

2017-11-01

Avascular necrosis of bone (AVN) leads to sclerosis and collapse of bone and joints. The standard of care, vascularized bone grafts, is limited by donor site morbidity and restricted availability. The aim of this study was to generate and test engineered, axially vascularized SVF cells-based bone substitutes in a rat model of AVN. SVF cells were isolated from lipoaspirates and cultured onto porous hydroxyapatite scaffolds within a perfusion-based bioreactor system for 5days. The resulting constructs were inserted into devitalized bone cylinders mimicking AVN-affected bone. A ligated vascular bundle was inserted upon subcutaneous implantation of constructs in nude rats. After 1 and 8weeks in vivo, bone formation and vascularization were analyzed. Newly-formed bone was found in 80% of SVF-seeded scaffolds after 8weeks but not in unseeded controls. Human ALU+cells in the bone structures evidenced a direct contribution of SVF cells to bone formation. A higher density of regenerative, M2 macrophages was observed in SVF-seeded constructs. In both experimental groups, devitalized bone was revitalized by vascularized tissue after 8 weeks. SVF cells-based osteogenic constructs revitalized fully necrotic bone in a challenging AVN rat model of clinically-relevant size. SVF cells contributed to accelerated initial vascularization, to bone formation and to recruitment of pro-regenerative endogenous cells. Avascular necrosis (AVN) of bone often requires surgical treatment with autologous bone grafts, which is surgically demanding and restricted by significant donor site morbidity and limited availability. This paper describes a de novo engineered axially-vascularized bone graft substitute and tests the potential to revitalize dead bone and provide efficient new bone formation in a rat model. The engineering of an osteogenic/vasculogenic construct of clinically-relevant size with stromal vascular fraction of human adipose, combined to an arteriovenous bundle is described. This construct revitalized and generated new bone tissue. This successful approach proposes a novel paradigm in the treatment of AVN, in which an engineered, vascularized osteogenic graft would be used as a germ to revitalize large volumes of necrotic bone. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Is the timing of surgery associated with avascular necrosis after unstable slipped capital femoral epiphysis? A multicenter study.

PubMed

Kohno, Yusuke; Nakashima, Yasuharu; Kitano, Toshio; Irie, Taichi; Kita, Atsushi; Nakamura, Tomoyuki; Endo, Hirosuke; Fujii, Yosuke; Kuroda, Takayuki; Mitani, Shigeru; Kitoh, Hiroshi; Matsushita, Masaki; Hattori, Tadashi; Iwata, Koji; Iwamoto, Yukihide

2017-01-01

An unstable slipped capital femoral epiphysis (SCFE) is associated with a high rate of avascular necrosis (AVN). The etiology of AVN seems to be multifactorial, although it is not thoroughly known. The aims of our study were to determine the rate of AVN after an unstable SCFE and to investigate the risk factors for AVN, specifically evaluating the notion of an "unsafe window", during which medical interventions would increase the risk for AVN. This retrospective multicenter study included 60 patients with an unstable SCFE diagnosed between 1985 and 2014. Timing of surgery was evaluated for three time periods, from acute onset of symptoms to surgery: period I, <24 h; period II, between 24 h and 7 days; and period III, >7 days. Multivariate logistic regression analysis was used to identify risk factors for AVN. Closed reduction and pinning was performed in 43 patients and in situ pinning in 17. Among these cases, 16 patients (27%) developed AVN. The rate of AVN was significantly higher in patients treated by closed reduction and pinning (15/43, 35%) than in those treated by in situ pinning (1/17, 5.9%) (p = 0.022). In patients treated by closed reduction and pinning, the incidence of AVN was 2/11 (18%) in period I, 10/13 (77%) in period II and 3/15 (20%) in period III, showing the significantly higher rate in period II (p = 0.002). The surgery provided in period II was identified as an independent risk factor for the development of AVN. Our rate of AVN was 27% using two classical treatment methods. Time-to-surgery, between 24 h and 7 days, was independently associated with AVN, supporting the possible existence of an "unsafe window" in patients with unstable SCFE treated by closed reduction and pinning. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Stem cell therapy for the treatment of early stage avascular necrosis of the femoral head: a systematic review

PubMed Central

2014-01-01

Background Avascular necrosis (AVN) of the femoral head (FH) is believed to be caused by a multitude of etiologic factors and is associated with significant morbidity in younger populations. Eventually, the disease progresses and results in FH collapse. Thus, a focus on early disease management aimed at joint preservation by preventing or delaying progression is key. The use of stem cells (SC) for the treatment of AVN of the FH has been proposed. We undertook a systematic review of the medical literature examining the use of SC for the treatment of early stage (precollapse) AVN of the FH, in both pre-clinical and clinical studies. Methods Data collected included: Pre-clinical studies – model of AVN, variety and dosage of SC, histologic and imaging analyses. Clinical studies – study design, classification and etiology of AVN, SC dosage and treatment protocol, incidence of disease progression, patient reported outcomes, volume of necrotic lesion and hip survivorship. Results In pre-clinical studies, the use of SC uniformly demonstrated improvements in osteogenesis and angiogenesis, yet source of implanted SC was variable. In clinical studies, groups treated with SC showed significant improvements in patient reported outcomes; however hip survivorship was not affected. Discrepancies regarding dose of SC, AVN etiology and disease severity were present. Conclusions Routine use of this treatment method will first require further research into dose and quality optimization as well as confirmed improvements in hip survivorship. PMID:24886648

Avascular necrosis of bone after allogeneic hematopoietic cell transplantation in children and adolescents.

PubMed

Li, Xiaxin; Brazauskas, Ruta; Wang, Zhiwei; Al-Seraihy, Amal; Baker, K Scott; Cahn, Jean-Yves; Frangoul, Haydar A; Gajewski, James L; Hale, Gregory A; Hsu, Jack W; Kamble, Rammurti T; Lazarus, Hillard M; Marks, David I; Maziarz, Richard T; Savani, Bipin N; Shah, Ami J; Shah, Nirali; Sorror, Mohamed L; Wood, William A; Majhail, Navneet S

2014-04-01

We conducted a nested case-control study within a cohort of 6244 patients to assess risk factors for avascular necrosis (AVN) of bone in children and adolescents after allogeneic transplantation. Eligible patients were ≤21 years of age, received their first allogeneic transplant between 1990 and 2008 in the United States, and had survived ≥ 6 months from transplantation. Overall, 160 patients with AVN and 478 control subjects matched by year of transplant, length of follow-up and transplant center were identified. Patients and control subjects were confirmed via central review of radiology, pathology, and/or surgical procedure reports. Median time from transplant to diagnosis of AVN was 14 months. On conditional logistic regression, increasing age at transplant (≥5 years), female gender, and chronic graft-versus-host disease (GVHD) were significantly associated with increased risks of AVN. Compared with patients receiving myeloablative regimens for malignant diseases, lower risks of AVN were seen in patients with nonmalignant diseases and those who had received reduced-intensity conditioning regimens for malignant diseases. Children at high risk for AVN include those within the age group where rapid bone growth occurs as well as those who experience exposure to myeloablative conditioning regimens and immunosuppression after hematopoietic cell transplantation for the treatment of GVHD. More research is needed to determine whether screening strategies specifically for patients at high risk for developing AVN with early interventions may mitigate the morbidity associated with this complication. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Avascular necrosis after chemotherapy for haematological malignancy in childhood.

PubMed

Salem, K H; Brockert, A-K; Mertens, R; Drescher, W

2013-12-01

Avascular necrosis (AVN) is a serious complication of high-dose chemotherapy for haematological malignancy in childhood. In order to describe its incidence and main risk factors and to evaluate the current treatment options, we reviewed 105 children with a mean age of 8.25 years (1 to 17.8) who had acute lymphoblastic or acute myeloid leukaemia, or a non-Hodgkin's lymphoma. Overall, eight children (7.6%) developed AVN after a mean of 16.8 months (8 to 49). There were four boys and four girls with a mean age of 14.4 years (9.8 to 16.8) and a total of 18 involved sites, 12 of which were in the femoral head. All these children were aged > nine years (p < 0.001). All had received steroid treatment with a mean cumulative dose of prednisone of 5967 mg (4425 to 9599) compared with a mean of 3943 mg (0 to 18 585) for patients without AVN (p = 0.005). No difference existed between genders and no thrombophilic disorders were identified. Their initial treatment included 11 core decompressions and two bipolar hip replacements. Later, two salvage osteotomies were done and three patients (four hips) eventually needed a total joint replacement. We conclude that AVN mostly affects the weight-bearing epiphyses. Its risk increases with age and higher steroid doses. These high-risk patients may benefit from early screening for AVN.

Avascular necrosis in children with cerebral palsy after reconstructive hip surgery

PubMed Central

Phillips, L.; Hesketh, K.; Schaeffer, E. K.; Andrade, J.; Farr, J.; Mulpuri, K.

2017-01-01

Abstract Purpose Progressive hip displacement is one of the most common orthopaedic pathologies in children with cerebral palsy (CP). Reconstructive hip surgery has become the standard treatment of care. Reported avascular necrosis (AVN) rates for hip reconstructive surgery in these patients vary widely in the literature. The purpose of this study is to identify the frequency and associated risk factors of AVN for reconstructive hip procedures. Methods A retrospective analysis was performed of 70 cases of reconstructive hip surgery in 47 children with CP, between 2009 and 2013. All 70 cases involved varus derotation osteotomy (VDRO), with 60% having combined VDRO and pelvic osteotomies (PO), and 21% requiring open reductions. Mean age at time of surgery was 8.82 years and 90% of patients were Gross Motor Function Classification System (GMFCS) 4 and 5. Radiographic dysplasia parameters were analysed at selected intervals, to a minimum of one year post-operatively. Severity of AVN was classified by Kruczynski's method. Bivar- iate statistical analysis was conducted using Chi-square test and Student's t-test. Results There were 19 (27%) noted cases of AVN, all radio- graphically identifiable within the first post-operative year. The majority of AVN cases (63%) were mild to moderate in severity. Pre-operative migration percentage (MP) (p = 0.0009) and post-operative change in MP (p = 0.002) were the most significant predictors of AVN. Other risk factors were: GMFCS level (p = 0.031), post-operative change in NSA (p = 0.02) and concomitant adductor tenotomy (0.028). Conclusion AVN was observed in 27% of patients. Severity of displacement correlates directly with AVN risk and we suggest that hip reconstruction, specifically VDRO, be performed early in the 'hip at risk' group to avoid this complication. PMID:29081846

Accuracy of enhanced and unenhanced MRI in diagnosing scaphoid proximal pole avascular necrosis and predicting surgical outcome.

PubMed

Fox, M G; Wang, D T; Chhabra, A B

2015-11-01

Determine the sensitivity, specificity and accuracy of unenhanced and enhanced MRI in diagnosing scaphoid proximal pole (PP) avascular necrosis (AVN) and correlate whether MRI can help guide the selection of a vascularized or nonvascularized bone graft. The study was approved by the IRB. Two MSK radiologists independently performed a retrospective review of unenhanced and enhanced MRIs from 18 patients (16 males, 2 females; median age, 17.5 years) with scaphoid nonunions and surgery performed within 65 days of the MRI. AVN was diagnosed on the unenhanced MRI when a diffusely decreased T1-W signal was present in the PP and on the enhanced MRI when PP enhancement was less than distal pole enhancement. Surgical absence of PP bleeding was diagnostic of PP AVN. Postoperative osseous union (OU) was assessed with computed tomography and/or radiographs. Sensitivity, specificity and accuracy for PP AVN were 71, 82 and 78% for unenhanced and 43, 82 and 67% for enhanced MRI. Patients with PP AVN on unenhanced MRI had 86% (6/7) OU; 100% (5/5) OU with vascularized bone grafts and 50% (1/2) OU with nonvascularized grafts. Patients with PP AVN on enhanced MRI had 80% (4/5) OU; 100% (3/3) OU with vascularized bone grafts and 50% (1/2) OU with nonvascularized grafts. Patients with viable PP on unenhanced and enhanced MRI had 91% (10/11) and 92% (12/13) OU, respectively, all but one with nonvascularized graft. When PP AVN is evident on MRI, OU is best achieved with vascularized grafts. If PP AVN is absent, OU is successful with nonvascularized grafts.

Avascular necrosis in children with cerebral palsy after reconstructive hip surgery.

PubMed

Phillips, L; Hesketh, K; Schaeffer, E K; Andrade, J; Farr, J; Mulpuri, K

2017-10-01

Progressive hip displacement is one of the most common orthopaedic pathologies in children with cerebral palsy (CP). Reconstructive hip surgery has become the standard treatment of care. Reported avascular necrosis (AVN) rates for hip reconstructive surgery in these patients vary widely in the literature. The purpose of this study is to identify the frequency and associated risk factors of AVN for reconstructive hip procedures. A retrospective analysis was performed of 70 cases of reconstructive hip surgery in 47 children with CP, between 2009 and 2013. All 70 cases involved varus derotation osteotomy (VDRO), with 60% having combined VDRO and pelvic osteotomies (PO), and 21% requiring open reductions. Mean age at time of surgery was 8.82 years and 90% of patients were Gross Motor Function Classification System (GMFCS) 4 and 5. Radiographic dysplasia parameters were analysed at selected intervals, to a minimum of one year post-operatively. Severity of AVN was classified by Kruczynski's method. Bivar- iate statistical analysis was conducted using Chi-square test and Student's t-test. There were 19 (27%) noted cases of AVN, all radio- graphically identifiable within the first post-operative year. The majority of AVN cases (63%) were mild to moderate in severity. Pre-operative migration percentage (MP) (p = 0.0009) and post-operative change in MP (p = 0.002) were the most significant predictors of AVN. Other risk factors were: GMFCS level (p = 0.031), post-operative change in NSA (p = 0.02) and concomitant adductor tenotomy (0.028). AVN was observed in 27% of patients. Severity of displacement correlates directly with AVN risk and we suggest that hip reconstruction, specifically VDRO, be performed early in the 'hip at risk' group to avoid this complication.

Early MRI Detection and Closed Bone Graft Epiphysiodesis May Alter the Course of Avascular Necrosis Following Unstable Slipped Capital Femoral Epiphysis.

PubMed

Napora, Joshua K; Gilmore, Allison; Son-Hing, Jochen P; Grimberg, Dominic C; Thompson, George H; Liu, Raymond W

2018-04-01

Unstable slipped capital femoral epiphysis (SCFE) has an increased incidence of avascular necrosis (AVN). Early identification and surgical intervention for AVN may help preserve the femoral head. We retrospectively reviewed 48 patients (50 hips) with unstable SCFE managed between 2000 and 2014. AVN was diagnosed based on 2 different postoperative protocols. Seventeen patients (17 hips) had a scheduled magnetic resonance imaging (MRI) between 1 and 6 months from initial surgery, and the remaining 31 patients (33 hips) were evaluated by plain radiographs alone. If AVN was diagnosed, we offered core decompression and closed bone graft epiphysiodesis (CBGE) to mitigate its affects. At final follow-up, we assessed progression of AVN using the Steinberg classification. Overall 13 hips (26%) with unstable SCFEs developed AVN. MRI revealed AVN in 7 of 17 hips (41%) at a mean of 2.5 months postoperatively (range, 1.0 to 5.2 mo). Six hips diagnosed by MRI received surgical intervention (4 CBGE, 1 free vascularized fibula graft, and 1 repinning due to screw cutout) at a mean of 4.1 months (range, 1.3 to 7.2 mo) postoperatively. None of the 4 patients treated with CBGE within 2 months postoperatively progressed to stage IVC AVN. The 2 patients treated after 4 months postoperatively both progressed to stage VC AVN.Plain radiographs demonstrated AVN in 6 of 33 hips (18%) at a mean of 6.8 months postoperatively (range, 2.1 to 21.1 mo). One patient diagnosed with stage IVB AVN at 2.4 months had screw cutout and received CBGE at 2.5 months from initial pinning. The remaining 5 were not offered surgical intervention. Five of the 6 radiographically diagnosed AVN, including the 1 treated with CBGE, progressed to stage IVC AVN or greater. Although all patients with positive MRI scans developed radiographic AVN, none of the 4 patients treated with CBGE within 2 months after pinning developed grade IVC or greater AVN. Early MRI detection and CBGE may mitigate the effects of AVN after SCFE. Level III-retrospective comparative study.

Stem cell- and growth factor-based regenerative therapies for avascular necrosis of the femoral head

PubMed Central

2012-01-01

Avascular necrosis (AVN) of the femoral head is a debilitating disease of multifactorial genesis, predominately affects young patients, and often leads to the development of secondary osteoarthritis. The evolving field of regenerative medicine offers promising treatment strategies using cells, biomaterial scaffolds, and bioactive factors, which might improve clinical outcome. Early stages of AVN with preserved structural integrity of the subchondral plate are accessible to retrograde surgical procedures, such as core decompression to reduce the intraosseous pressure and to induce bone remodeling. The additive application of concentrated bone marrow aspirates, ex vivo expanded mesenchymal stem cells, and osteogenic or angiogenic growth factors (or both) holds great potential to improve bone regeneration. In contrast, advanced stages of AVN with collapsed subchondral bone require an osteochondral reconstruction to preserve the physiological joint function. Analogously to strategies for osteochondral reconstruction in the knee, anterograde surgical techniques, such as osteochondral transplantation (mosaicplasty), matrix-based autologous chondrocyte implantation, or the use of acellular scaffolds alone, might preserve joint function and reduce the need for hip replacement. This review summarizes recent experimental accomplishments and initial clinical findings in the field of regenerative medicine which apply cells, growth factors, and matrices to address the clinical problem of AVN. PMID:22356811

Leptin ameliorates ischemic necrosis of the femoral head in rats with obesity induced by a high-fat diet.

PubMed

Zhou, Lu; Jang, Kyu Yun; Moon, Young Jae; Wagle, Sajeev; Kim, Kyoung Min; Lee, Kwang Bok; Park, Byung-Hyun; Kim, Jung Ryul

2015-03-23

Obesity is a risk factor for ischemic necrosis of the femoral head (INFH). The purpose of this study was to determine if leptin treatment of INFH stimulates new bone formation to preserve femoral head shape in rats with diet-induced obesity. Rats were fed a high-fat diet (HFD) or normal chow diet (NCD) for 16 weeks to induce progressive development of obesity. Avascular necrosis of the femoral head (AVN) was surgically induced. Adenovirus-mediated introduction of the leptin gene was by intravenous injection 2 days before surgery-induced AVN. At 6 weeks post-surgery, radiologic and histomorphometric assessments were performed. Leptin signaling in tissues was examined by Western blot. Osteogenic markers were analyzed by real-time RT-PCR. Radiographs showed better preservation of femoral head architecture in the HFD-AVN-Leptin group than the HFD-AVN and HFD-AVN-LacZ groups. Histology and immunohistochemistry revealed the HFD-AVN-Leptin group had significantly increased osteoblastic proliferation and vascularity in infarcted femoral heads compared with the HFD-AVN and HFD-AVN-LacZ groups. Intravenous injection of leptin enhanced serum VEGF levels and activated HIF-1α pathways. Runx 2 and its target genes were significantly upregulated in the HFD-AVN-Leptin group. These results indicate that leptin resistance is important in INFH pathogenesis. Leptin therapy could be a new strategy for INFH.

Leptin ameliorates ischemic necrosis of the femoral head in rats with obesity induced by a high-fat diet

PubMed Central

Zhou, Lu; Jang, Kyu Yun; Moon, Young Jae; Wagle, Sajeev; Kim, Kyoung Min; Lee, Kwang Bok; Park, Byung-Hyun; Kim, Jung Ryul

2015-01-01

Obesity is a risk factor for ischemic necrosis of the femoral head (INFH). The purpose of this study was to determine if leptin treatment of INFH stimulates new bone formation to preserve femoral head shape in rats with diet-induced obesity. Rats were fed a high-fat diet (HFD) or normal chow diet (NCD) for 16 weeks to induce progressive development of obesity. Avascular necrosis of the femoral head (AVN) was surgically induced. Adenovirus-mediated introduction of the leptin gene was by intravenous injection 2 days before surgery-induced AVN. At 6 weeks post-surgery, radiologic and histomorphometric assessments were performed. Leptin signaling in tissues was examined by Western blot. Osteogenic markers were analyzed by real-time RT-PCR. Radiographs showed better preservation of femoral head architecture in the HFD-AVN-Leptin group than the HFD-AVN and HFD-AVN-LacZ groups. Histology and immunohistochemistry revealed the HFD-AVN-Leptin group had significantly increased osteoblastic proliferation and vascularity in infarcted femoral heads compared with the HFD-AVN and HFD-AVN-LacZ groups. Intravenous injection of leptin enhanced serum VEGF levels and activated HIF-1α pathways. Runx 2 and its target genes were significantly upregulated in the HFD-AVN-Leptin group. These results indicate that leptin resistance is important in INFH pathogenesis. Leptin therapy could be a new strategy for INFH. PMID:25797953

Symptomatic Avascular Necrosis: An Understudied Risk Factor for Acute Care Utilization by Patients with SCD

PubMed Central

Yu, Tiffany; Campbell, Timothy; Ciuffetelli, Isabella; Haywood, Carlton; Carroll, C. Patrick; Resar, Linda M.S.; Strouse, John J.; Lanzkron, Sophie

2016-01-01

Objectives Sickle cell disease (SCD) is associated with high healthcare utilization rates and poor outcomes in a subset of patients, although the underlying factors that predict this phenotype are poorly understood. Prior studies suggest that comorbid avascular necrosis (AVN) contributes to high healthcare utilization. We sought to clarify whether AVN independently predicts acute care utilization in adults with SCD and to identify characteristics of those with AVN that predict higher utilization. Methods We reviewed the medical records of 87 patients with SCD with symptomatic AVN and compared acute care utilization and clinical characteristics with 87 sex- and age-matched patients with SCD without symptomatic AVN. Patients with ≥2 years of follow-up were included. Outcomes were compared using bivariate analysis and multivariate regression. Results Our study included 1381 follow-up years, with a median of 7 years per patient. The AVN cohort had greater median rates of urgent care visits (3.2/year vs 1.3/year; P = 0.0155), admissions (1.3/year vs 0.4/year; P = 0.0002), and admission days (5.1 days/year vs 1.8 days/year; P = 0.0007). History of high utilization (odds ratio [OR] 4.28; P = 0.001), acute chest syndrome (OR 3.12; P = 0.005), pneumonia (OR 3.20; P = 0.023), hydroxyurea therapy (OR 2.23; P = 0.0136), and long-term transfusion (OR 2.33; P = 0.014) were associated with AVN. In a median regression model, AVN, acute chest syndrome, and pneumonia were independently associated with greater urgent care visits and admissions. Conclusions Symptomatic AVN was found to be an independent risk factor for acute care utilization in patients with SCD. Because this is a potentially modifiable factor, further studies are urgently needed to determine whether AVN prevention/early treatment interventions will alter utilization and improve outcomes for patients with SCD. PMID:27598353

Symptomatic Avascular Necrosis: An Understudied Risk Factor for Acute Care Utilization by Patients with SCD.

PubMed

Yu, Tiffany; Campbell, Timothy; Ciuffetelli, Isabella; Haywood, Carlton; Carroll, Christopher Patrick; Resar, Linda; Strouse, John J; Lanzkron, Sophie

2016-09-01

Sickle cell disease (SCD) is associated with high healthcare utilization rates and poor outcomes in a subset of patients, although the underlying factors that predict this phenotype are poorly understood. Prior studies suggest that comorbid avascular necrosis (AVN) contributes to high healthcare utilization. We sought to clarify whether AVN independently predicts acute care utilization in adults with SCD and to identify characteristics of those with AVN that predict higher utilization. We reviewed the medical records of 87 patients with SCD with symptomatic AVN and compared acute care utilization and clinical characteristics with 87 sex- and age-matched patients with SCD without symptomatic AVN. Patients with ≥2 years of follow-up were included. Outcomes were compared using bivariate analysis and multivariate regression. Our study included 1381 follow-up years, with a median of 7 years per patient. The AVN cohort had greater median rates of urgent care visits (3.2/year vs 1.3/year; P = 0.0155), admissions (1.3/year vs 0.4/year; P = 0.0002), and admission days (5.1 days/year vs 1.8 days/year; P = 0.0007). History of high utilization (odds ratio [OR] 4.28; P = 0.001), acute chest syndrome (OR 3.12; P = 0.005), pneumonia (OR 3.20; P = 0.023), hydroxyurea therapy (OR 2.23; P = 0.0136), and long-term transfusion (OR 2.33; P = 0.014) were associated with AVN. In a median regression model, AVN, acute chest syndrome, and pneumonia were independently associated with greater urgent care visits and admissions. Symptomatic AVN was found to be an independent risk factor for acute care utilization in patients with SCD. Because this is a potentially modifiable factor, further studies are urgently needed to determine whether AVN prevention/early treatment interventions will alter utilization and improve outcomes for patients with SCD.

Closed bone graft epiphysiodesis for avascular necrosis of the capital femoral epiphysis.

PubMed

Thompson, George H; Lea, Ethan S; Chin, Kenneth; Liu, Raymond W; Son-Hing, Jochen P; Gilmore, Allison

2013-07-01

Avascular necrosis (AVN) of the capital femoral epiphysis (CFE) after an unstable slipped capital femoral epiphysis (SCFE), femoral neck fracture or traumatic hip dislocation can result in severe morbidity. Treatment options for immature patients with AVN are limited, including a closed bone graft epiphysiodesis (CBGE). However, it is unclear whether this procedure prevents AVN progression. We investigated whether early MRI screening and CBGE prevented the development of advanced AVN changes in the CFE and the rates of complications with this approach. We prospectively followed all 13 patients (seven boys, six girls) with unstable SCFEs (six patients), femoral neck fractures (five patients), and traumatic hip dislocations (two patients) and evidence of early AVN treated between 1984 and 2012. Mean age at initial injury was 12 years (range, 10-16 years). Nine of the 13 patients had followup of at least 2 years or until conversion to THA (mean, 4.5 years; range, 0.8-8.5 years), including two with unstable SCFEs, the five with femoral neck fractures, and the two with traumatic hip dislocations. All patients had technetium scans and/or MRI within 1 to 2 months of their initial injury (before CBGE) and all had evidence of early (Ficat 0) AVN. Patients were followed clinically and radiographically for AVN progression. Six of the nine hips did not develop typical clinical or radiographic evidence of AVN. These six patients have been followed 6.3 years (range, 4.3-9.1 years) from initial injury and 5.9 years (range, 3.8-8.5 years) from CBGE. The remaining three patients were diagnosed with AVN at periods ranging from 3 to 6 months after CBGE. Early recognition and treatment of AVN with a CBGE may alter the natural history of this complication. Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Inter-observer and intra-observer reliability in the radiographic diagnosis of avascular necrosis of the femoral head following reconstructive hip surgery in children with cerebral palsy.

PubMed

Hesketh, Kim; Sankar, Wudbhav; Joseph, Benjamin; Narayanan, Unni; Mulpuri, Kishore

2016-04-01

The incidence of avascular necrosis (AVN) following reconstructive hip surgery in cerebral palsy (CP) ranges from 0 to 69 % in the current literature. The purpose of this study was to determine the inter- and intra-observer reliability of radiographically diagnosing AVN in children with CP after hip surgery. A retrospective review of 65 children with CP who had reconstructive hip surgery between 2009 and 2012 at BC Children's Hospital was completed. Anterior-posterior and lateral radiographs were presented to four pediatric orthopaedic surgeons over two rounds. Surgeons were asked to review the set of unidentified radiographs and comment 'yes' or 'no' for the presence of AVN. Two weeks later the same set of radiographs was sent in a different order and the surgeons were again asked to comment on AVN. Inter- and intra-observer reliability was determined using kappa statistics. The intra-observer reliability ranged from 0.65 to 0.88 with an average score of 0.76. Inter-observer reliability showed greater variability, ranging from 0.41 to 0.77 with an average score of 0.56 across all surgeons. Although the intra-rater reliability produced a strength of "good" and the inter-rater reliability a strength of "moderate" agreement, the variability within these scores is clinically important as it demonstrates the difficulty in identifying AVN. This may explain the variability in AVN that is reported in the literature. The need for further education and research in the diagnosis of AVN in children with CP who have undergone reconstructive hip surgery is clinically necessary.

Tribological changes in the articular cartilage of a human femoral head with avascular necrosis.

PubMed

Seo, Eun-Min; Shrestha, Suman K; Duong, Cong-Truyen; Sharma, Ashish Ranjan; Kim, Tae-Woo; Vijayachandra, Ayyappan; Thompson, Mark S; Cho, Myung Guk; Park, Sungchan; Kim, Kwanghoon; Park, Seonghun; Lee, Sang-Soo

2015-06-29

The present study evaluated the tribological properties of the articular cartilage surface of the human femoral head with postcollapse stage avascular necrosis (AVN) using atomic force microscopy. The cartilage surface in the postcollapse stage AVN of the femoral head was reported to resemble those of disuse conditions, which suggests that the damage could be reversible and offers the possibilities of success of head-sparing surgeries. By comparing the tribological properties of articular cartilage in AVN with that of osteoarthritis, the authors intended to understand the cartilage degeneration mechanism and reversibility of AVN. Human femoral heads with AVN were explanted from the hip replacement surgery of four patients (60-83 years old). Nine cylindrical cartilage samples (diameter, 5 mm and height, 0.5 mm) were sectioned from the weight-bearing areas of the femoral head with AVN, and the cartilage surface was classified according to the Outerbridge Classification System (AVN0, normal; AVN1, softening and swelling; and AVN2, partial thickness defect and fissuring). Tribological properties including surface roughness and frictional coefficients and histochemistry including Safranin O and lubricin staining were compared among the three groups. The mean surface roughness Rq values of AVN cartilage increased significantly with increasing Outerbridge stages: Rq = 137 ± 26 nm in AVN0, Rq = 274 ± 49 nm in AVN1, and Rq = 452 ± 77 nm in AVN2. Significant differences in Rq were observed among different Outerbridge stages in all cases (p < 0.0001). The frictional coefficients (μ) also increased with increasing Outerbridge stages. The frictional coefficient values were μ = 0.115 ± 0.034 in AVN0, μ = 0.143 ± 0.025 in AVN1, and μ = 0.171 ± 0.039 in AVN2. Similarly to the statistical analysis of surface roughness, significant statistical differences were detected between different Outerbridge stages in all cases (p < 0.05). Both surface roughness and frictional coefficient of cartilage, which were linearly correlated, increased with increasing Outerbridge stages in postcollapse AVN. The underlying mechanism of these results can be related to proteoglycan loss within the articular cartilage that is also observed in osteoarthritis. With regard to the tribological properties, the cartilage degeneration mechanism in AVN was similar to that of osteoarthritis without reversibility.

Core decompression and biotechnologies in the treatment of avascular necrosis of the femoral head

PubMed Central

Calori, Giorgio Maria; Mazza, Emilio; Colombo, Alessandra; Mazzola, Simone; Colombo, Massimiliano

2017-01-01

Avascular necrosis (AVN) of the femoral head (FH) causes 5% to 12% of total hip arthroplasties (THA). It especially affects active male adults between the third and fifth decades of life. The exact worldwide incidence is unknown. There are only few data related to each country, but most of it relates to the United States. Non-surgical management has a very limited role in the treatment of AVN of the FH and only in its earliest stages. Core decompression (CD) of the hip is the most common procedure used to treat the early stages of AVN of the FH. Recently, surgeons have considered combining CD with autologous bone-marrow cells, demineralised bone matrix or bone morphogenetic proteins or methods of angiogenic potential to enhance bone repair in the FH. Manuscripts were deemed eligible for our review if they evaluated treatment of early stage AVN of the FH with biotechnology implanted via CD. After application of eligibility criteria, we selected 19 reports for final analysis. The principal results showed that only by correctly mastering the therapeutic principles and adopting proper methods specifically oriented to different stages can the best therapeutic effect be achieved. Combining CD with biotechnology could result in a novel long-lasting hip- preserving treatment option. Furthermore, more refined clinical studies are needed to establish the effectiveness of biotechnology treatments in AVN of the FH. Cite this article: EFORT Open Rev 2017;2:41-50. DOI: 10.1302/2058-5241.2.150006 PMID:28461967

Core decompression and biotechnologies in the treatment of avascular necrosis of the femoral head.

PubMed

Calori, Giorgio Maria; Mazza, Emilio; Colombo, Alessandra; Mazzola, Simone; Colombo, Massimiliano

2017-02-01

Avascular necrosis (AVN) of the femoral head (FH) causes 5% to 12% of total hip arthroplasties (THA). It especially affects active male adults between the third and fifth decades of life. The exact worldwide incidence is unknown. There are only few data related to each country, but most of it relates to the United States.Non-surgical management has a very limited role in the treatment of AVN of the FH and only in its earliest stages. Core decompression (CD) of the hip is the most common procedure used to treat the early stages of AVN of the FH. Recently, surgeons have considered combining CD with autologous bone-marrow cells, demineralised bone matrix or bone morphogenetic proteins or methods of angiogenic potential to enhance bone repair in the FH.Manuscripts were deemed eligible for our review if they evaluated treatment of early stage AVN of the FH with biotechnology implanted via CD. After application of eligibility criteria, we selected 19 reports for final analysis.The principal results showed that only by correctly mastering the therapeutic principles and adopting proper methods specifically oriented to different stages can the best therapeutic effect be achieved. Combining CD with biotechnology could result in a novel long-lasting hip- preserving treatment option.Furthermore, more refined clinical studies are needed to establish the effectiveness of biotechnology treatments in AVN of the FH. Cite this article: EFORT Open Rev 2017;2:41-50. DOI: 10.1302/2058-5241.2.150006.

Administrative Algorithms to identify Avascular necrosis of bone among patients undergoing upper or lower extremity magnetic resonance imaging: a validation study.

PubMed

Barbhaiya, Medha; Dong, Yan; Sparks, Jeffrey A; Losina, Elena; Costenbader, Karen H; Katz, Jeffrey N

2017-06-19

Studies of the epidemiology and outcomes of avascular necrosis (AVN) require accurate case-finding methods. The aim of this study was to evaluate performance characteristics of a claims-based algorithm designed to identify AVN cases in administrative data. Using a centralized patient registry from a US academic medical center, we identified all adults aged ≥18 years who underwent magnetic resonance imaging (MRI) of an upper/lower extremity joint during the 1.5 year study period. A radiologist report confirming AVN on MRI served as the gold standard. We examined the sensitivity, specificity, positive predictive value (PPV) and positive likelihood ratio (LR + ) of four algorithms (A-D) using International Classification of Diseases, 9th edition (ICD-9) codes for AVN. The algorithms ranged from least stringent (Algorithm A, requiring ≥1 ICD-9 code for AVN [733.4X]) to most stringent (Algorithm D, requiring ≥3 ICD-9 codes, each at least 30 days apart). Among 8200 patients who underwent MRI, 83 (1.0% [95% CI 0.78-1.22]) had AVN by gold standard. Algorithm A yielded the highest sensitivity (81.9%, 95% CI 72.0-89.5), with PPV of 66.0% (95% CI 56.0-75.1). The PPV of algorithm D increased to 82.2% (95% CI 67.9-92.0), although sensitivity decreased to 44.6% (95% CI 33.7-55.9). All four algorithms had specificities >99%. An algorithm that uses a single billing code to screen for AVN among those who had MRI has the highest sensitivity and is best suited for studies in which further medical record review confirming AVN is feasible. Algorithms using multiple billing codes are recommended for use in administrative databases when further AVN validation is not feasible.

Early treatment with the von Rosen splint for neonatal instability of the hip is safe regarding avascular necrosis of the femoral head

PubMed Central

Wenger, Daniel; Samuelsson, Hanna; Düppe, Henrik; Tiderius, Carl Johan

2016-01-01

Background and purpose — Avascular necrosis of the femoral head (AVN) is a complication in treatment of developmental dysplasia of the hip (DDH). We evaluated the risk of AVN after early treatment in the von Rosen splint and measured the diameter of the ossific nucleus at 1 year of age. Children and methods — All children born in Malmö, Sweden, undergo clinical screening for neonatal instability of the hip (NIH). We reviewed 1-year radiographs of all children treated early for NIH in our department from 2003 through 2010. The diameter of the ossific nucleus was measured, and signs of AVN were classified according to Kalamchi-MacEwen. Subsequent radiographs, taken for any reason, were reviewed and a local registry of diagnoses was used to identify subsequent AVN. Results — 229 of 586 children referred because of suspected NIH received early treatment (age ≤ 1 week) for NIH during the study period. 2 of the 229 treated children (0.9%, 95% CI: 0.1–3.1) had grade-1 AVN. Both had spontaneous resolution and were asymptomatic during the observation time (6 and 8 years). 466 children met the inclusion criteria for measurement of the ossific nucleus. Neonatally dislocated hips had significantly smaller ossific nuclei than neonatally stable hips: mean 9.4 mm (95% CI: 9.1–9.8) vs. 11.1 mm (95% CI: 10.9–11.3) at 1 year (p < 0.001). Interpretation — Early treatment with the von Rosen splint for NIH is safe regarding AVN. The ossification of the femoral head is slower in children with NIH than in untreated children with neonatally stable hips. PMID:26730503

Spontaneous resolution of avascular necrosis of femoral heads following cure of Cushing's syndrome.

PubMed

Pazderska, A; Crowther, S; Govender, P; Conlon, K C; Sherlock, M; Gibney, J

2016-01-01

Avascular necrosis (AVN) is a rare presenting feature of endogenous hypercortisolism. If left untreated, complete collapse of the femoral head may ensue, necessitating hip replacement in up to 70% of patients. The majority of the described patients with AVN due to endogenous hypercortisolaemia required surgical intervention. A 36-year-old female, investigated for right leg pain, reported rapid weight gain, bruising and secondary amenorrhoea. She had abdominal adiposity with violaceous striae, facial plethora and hirsutism, atrophic skin, ecchymosis and proximal myopathy. Investigations confirmed cortisol excess (cortisol following low-dose 48h dexamethasone suppression test 807nmol/L; 24h urinary free cortisol 1443nmol (normal<290nmol)). Adrenocorticotrophic hormone (ACTH) was <5.0pg/mL. CT demonstrated subtle left adrenal gland hypertrophy. Hypercortisolaemia persisted after left adrenalectomy. Histology revealed primary pigmented micronodular adrenal disease. Post-operatively, right leg pain worsened and left leg pain developed, affecting mobility. MRI showed bilateral femoral head AVN. She underwent right adrenalectomy and steroid replacement was commenced. Four months after surgery, leg pain had resolved and mobility was normal. Repeat MRI showed marked improvement of radiological abnormalities in both femoral heads, consistent with spontaneous healing of AVN. We report a case of Cushing's syndrome due to primary pigmented nodular adrenocortical disease, presenting with symptomatic AVN of both hips. This was managed conservatively from an orthopaedic perspective. Following cure of hypercortisolaemia, the patient experienced excellent recovery and remains symptom free 4 years after adrenalectomy. This is the first report of a favourable outcome over long-term follow-up of a patient with bilateral AVN of the hip, which reversed with treatment of endogenous hypercortisolaemia. AVN of femoral head can be a presenting feature of hypercortisolism, both endogenous and exogenous.Rarely, treatment of hypercortisolaemia can reverse AVN without the need for orthopaedic intervention.Primary pigmented nodular adrenal disease is a rare cause of ACTH-independent Cushing's syndrome.

Bilateral avascular necrosis of the femoral head following asynchronous postictal femoral neck fractures: a case report and review of the literature.

PubMed

Venkatadass, K; Avinash, M; Rajasekaran, S

2018-05-01

Bilateral avascular necrosis (AVN) following postictal bilateral fracture neck of the femur is a rare occurrence. Here, we report a case of bilateral AVN of the femoral head following an asynchronous bilateral postictal fracture neck of the femur. A 16-year-old autistic boy presented with left hip pain following an episode of seizures and radiographs showed Delbet type II fracture neck of the left femur. This was treated by closed reduction and cancellous screw fixation and skeletal traction for 6 weeks. At 3 months, follow-up radiograph showed union of the fracture, but he had developed segmental AVN with collapse of the head. At 8 months, the patient presented with pain in the right hip following another episode of seizures and radiograph of the pelvis showed a fresh Delbet type II fracture neck of the right femur with established AVN of the left femoral head. He underwent closed reduction and cancellous screw fixation of the right hip and implant exit of the left hip. At the 6-month follow-up after this surgery, his radiograph of the pelvis showed AVN with collapse and extrusion of the femoral head on the right side as well. Literature review shows an increased risk of fracture neck of the femur among epileptics. The incidence of AVN is maximum in Delbet type I, followed by Delbet type II and type III in that order. Although there are no clear guidelines on the management of post-traumatic AVN of the femoral head, the majority have reported that most of them will eventually develop arthritis and will require total hip replacement at a later date. Upon extensive literature search, no case report of bilateral fracture neck of the femur with bilateral AVN was found and hence this case was reported.

Prevalence, incidence, and associated factors of avascular necrosis in Korean patients with systemic lupus erythematosus: a nationwide epidemiologic study.

PubMed

Joo, Young Bin; Sung, Yoon-Kyoung; Shim, Jee-Seon; Kim, Jae-Hoon; Lee, Eui-Kyung; Lee, Hye-Soon; Bae, Sang-Cheol

2015-05-01

Avascular necrosis (AVN) is one of the most frequent types of organ damage in systemic lupus erythematosus (SLE). However, little is currently known about the epidemiology of AVN in SLE patients. The aim of this study was to estimate the prevalence and incidence of AVN in Korean patients with SLE based on National Health Insurance (NHI) claims data and to determine the risk factors for AVN among SLE patients. This study was conducted using the 2006-2010 data of 25,358 SLE patients from the NHI program. AVN cases were defined as those with at least one diagnosis of AVN. The prevalence was calculated by dividing the number of AVN cases by the number of SLE cases in the same year. The annual incidence was calculated by dividing the number of incident AVN cases by the number of SLE-prevalent cases not previously diagnosed with AVN. Patients who developed AVN in 2008-2010 were compared with SLE patients who did not develop AVN to identify any risk factors. The prevalence of AVN among SLE patients (2006-2010) was 31.5-34.2 per 1,000 persons and was similar in all the years studied. The incidence per 1,000 persons of AVN among SLE patients was 8.6 [95 % confidence interval (95 % CI) 6.9-10.3] in 2008, 9.8 (95 % CI 8.0-11.6) in 2009, and 8.4 (95 % CI 6.8-10.0) in 2010. Regression analysis indicated that taking an oral corticosteroid [odds ratio (OR) 2.12, 95 % CI 1.39-3.23] or an intravenous corticosteroid (OR 1.5, 95 % CI 1.2-1.89) was significantly associated with AVN. In addition, AVN was associated with use of immunosuppressive agents (OR 2.12, 95 % CI 1.66-2.72), hydroxychloroquine (OR 1.4, 95 % CI 1.09-1.81), and lipid-lowering agents (OR 1.78, 95 % CI 1.24-2.57) among the prescribed medications, and with hypertension (OR 1.39, 95 % CI 1.08-1.79) among the comorbidities. The prevalence and incidence of AVN among SLE patients, which were 31.5-34.2 and 8.4-9.8 per 1,000 persons, respectively, may be representative of the entire population of symptomatic AVN patients with SLE in Korea. AVN is associated with the use of corticosteroids, immunosuppressants, hydroxychloroquine, lipid-lowering agents, and with hypertension. Studies of large, prospective cohorts are needed to confirm these results.

Time trend and risk factors of avascular bone necrosis in patients with systemic lupus erythematosus.

PubMed

Tse, Sau Mei; Mok, Chi Chiu

2017-06-01

Objectives The objective of this paper is to study the time trend and risk factors of avascular bone necrosis (AVN) in patients with systemic lupus erythematosus (SLE). Methods Between 1999 and 2014, patients who fulfilled the ACR criteria for SLE and developed symptomatic AVN were identified from our cohort database and compared with those without AVN, matched for age, sex and SLE duration. The standardized incidence ratios (SIRs) of AVN in different SLE age groups were calculated from data derived from our hospital registry and population census. Risk factors for AVN were studied by logistic regression, adjusted by a propensity score for ever use of high-dose glucocorticoids (GCs). Results Fifty-five SLE patients with AVN and 220 SLE patients without AVN were studied. There were 104 AVN sites involved, with the hips being most commonly affected (82%). The point prevalence of AVN in our SLE cohort was 7.4%. The SIRs of AVN in our SLE patients were 131 (86.6-199; p < 0.001) and 56.0 (34.3-91.4; p < 0.001), respectively, in the periods 1995-2004 and 2005-2014. In both decades, the age-stratified SIR was highest in the youngest age group (<19 years). AVN patients were more likely to be treated with GCs and had received a significantly higher cumulative dose of prednisolone since SLE diagnosis (16.5 vs 10.7 grams; p = 0.001). The SLE damage score (excluding AVN) was also significantly higher in AVN than non-AVN patients (2.5 vs 0.4; p < 0.001). Logistic regression revealed that preceding septic arthritis of the involved joint (odds ratio (OR) 17.7 (1.5-205); p = 0.02), cushingoid body habitus (OR 2.4 (1.1-5.2); p = 0.04), LDL cholesterol level (OR 1.4 (1.0-1.9); p = 0.04), maximum daily dose of prednisolone (OR 6.4 (1.2-33.3); p = 0.03) and cumulative dose of prednisolone received in the first six months of the first lupus flare (OR 1.3 (1.0-1.8); p = 0.046) were independently associated with AVN. Conclusions AVN is prevalent in SLE, particularly in younger patients. The use of GCs remains the strongest independent risk factor. A trend of reduction in the SIR of AVN in our SLE patients is observed over the past two decades.

Retrograde intramedullary nail arthrodesis for avascular necrosis of the talus.

PubMed

Devries, J George; Philbin, Terrence M; Hyer, Christopher F

2010-11-01

Avascular necrosis (AVN) of the talus from any etiology is a devastating pathology. There are few salvage options available and controversy exists as to the surgical management for patients with talar AVN. The authors present their results of tibiotalocalcaneal arthrodesis with a retrograde nail. A comprehensive chart and radiographic review was pulled from our database for patients with AVN of the talus, who were treated by tibiotalocalcaneal fusion with retrograde intramedullary nail. Primary outcome was union, with time to clinical union as a secondary endpoint. Fourteen patients were included. The average age at surgery was 47.4 ± 12.8 years, there were nine female patients, and the average Body Mass Index was 33.5 ± 6.0. Surgical risk factors included two patients who smoked, one was diabetic, and one had a preoperative ulceration. The average time to partial weightbearing was 70.6 ± 25.4 days, and the average time to full weightbearing was 100.6 ± 35.5 days. Four patients had postoperative complications, while no patients required major revision surgery. Twelve patients went on to solid fusion, while two went on to a stable, braceable pseudoarthrosis. Eight patients were able to return to shoes, and eight were able to walk unaided at final followup. Salvage of talar AVN is possible by tibiotalocalcaneal arthrodesis with an intramedullary nail. Physicians may offer this as a salvage option to patients with a high likelihood of successful fusion.

Synergistic effect of cumulative corticosteroid dose and immunosuppressants on avascular necrosis in patients with systemic lupus erythematosus.

PubMed

Kwon, H H; Bang, S Y; Won, S; Park, Y; Yi, J H; Joo, Y B; Lee, H S; Bae, S C

2018-01-01

Objectives Avascular necrosis (AVN) is one of the most common causes of organ damage in patients with systemic lupus erythematosus (SLE) and often causes serious physical disability. The aims of this study were to investigate clinical risk factors associated with symptomatic AVN and to analyze their synergistic effects in a large SLE cohort in Korea. Methods Patients with SLE were enrolled and followed from 1998 to 2014 in the Hanyang BAE Lupus cohort, and damage was measured annually according to the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). AVN was confirmed by imaging study if patients had symptoms. To determine risk factors for AVN, clinical, laboratory and therapeutic variables were analyzed by logistic regression. Relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (S) were calculated to measure interactions between significant variables. Results Among 1219 SLE patients, symptomatic AVN was the most common type of musculoskeletal damage (10.8%, n = 132). SLE patients with AVN showed an earlier onset age, demonstrated AVN more commonly in conjunction with certain other clinical manifestations such as renal and neuropsychiatric disorders, and received significantly higher total cumulative corticosteroid dose and immunosuppressive agents than did patients without AVN. However, in multivariable analysis, only two variables including use of a cumulative corticosteroid dose greater than 20 g (odds ratio (OR) 3.62, p = 0.015) and use of immunosuppressants including cyclophosphamide or mycophenolate mofetil (OR 4.51, p < 0.001) remained as significant risk factors for AVN. Patients with cumulative corticosteroid dose > 20 g and immunosuppressant use had a 15.44-fold increased risk for AVN, compared with patients without these risk factors ( p < 0.001). RERI, AP and S, which define the strength of interactions between two risk factors, were 9.01 (95% confidence interval (CI) 1.30-16.73), 0.58 (95% CI 0.36-0.81) and 2.66 (95% CI 1.42-4.99), respectively, supporting the presence of synergistic interactions in the development of symptomatic AVN in our Korean lupus cohort. Conclusions An individual risk assessment for AVN development should be made prior to and during treatment for SLE, especially in patients with high-dose corticosteroid and immunosuppressant use regardless of clinical manifestations and disease activity.

Risk factors for avascular necrosis after closed reduction for developmental dysplasia of the hip.

PubMed

Schur, Mathew D; Lee, Christopher; Arkader, Alexandre; Catalano, Anthony; Choi, Paul D

2016-06-01

The purpose of this study was to identify and evaluate risk factors of avascular necrosis (AVN) after closed treatment for developmental dysplasia of the hip (DDH). A retrospective review of children diagnosed with DDH at a tertiary-care children's hospital between 1986 and 2009 was performed. The presence of AVN was assessed according to Salter's classification system. Eighty-two affected hips in 70 children with an average age of 10 months at closed reduction (range 1-31 months) and 5 years (range 2-19 years) of follow-up met the inclusion criteria. Twenty-nine (of 82, 35 %) affected hips developed AVN. The use of pre-reduction traction (p = 0.019) increased the risk of AVN, while preoperative Pavlik harness or brace trial (p = 0.28), presence of ossific nucleus at the time of closed reduction (p = 0.16), and adductor tenotomy (p = 0.37) were not significant factors. Laterality (right vs. left) was also not a significant risk factor (p = 0.75), but patients who underwent closed reduction for bilateral DDH were less likely to develop AVN (p = 0.027). Overall, the degree of abduction did not affect the rate of AVN (p = 0.87). However, in patients treated with closed reduction younger than 6 months of age, the rate of AVN was increased with abduction ≥50° (9/15, 60 %) compared to abduction <50° (0/8, 0 %) (p = 0.007). Patients who developed AVN were more likely to require subsequent surgery (p = 0.034) and more likely to report a fair/poor clinical outcome (p = 0.049). The risk of AVN (35 %) following closed reduction and spica casting for DDH is high. The degree of abduction in spica casts appears to be a risk factor in patients ≤6 months old. The authors recommend that abduction in spica casts should be limited to <50° in children younger than 6 months of age. IV.

Management Options in Avascular Necrosis of Talus.

PubMed

Dhillon, Mandeep S; Rana, Balvinder; Panda, Inayat; Patel, Sandeep; Kumar, Prasoon

2018-01-01

Avascular necrosis (AVN) of the talus can be a cause of significant disability and is a difficult problem to treat. The most common cause is a fracture of the talus. We have done a systematic review of the literature with the following aims: (1) identify and summarize the available evidence in literature for the treatment of talar AVN, (2) define the usefulness of radiological Hawkins sign and magnetic resonance imaging in early diagnosis, and (3) provide patient management guidelines. We searched MEDLINE and PUBMED using keywords and MESH terminology. The articles' abstracts were read by two of the authors. Forty-one studies met the inclusion criteria of the 335 abstracts screened. The interventions of interest included hindfoot fusion, conservative measures, bone grafting, vascularized bone graft, core decompression, and talar replacement. All studies were of Level IV evidence. We looked to identify the study quality, imprecise and sparse data, reporting bias, and the quality of evidence. Based on the analysis of available literature, we make certain recommendations for managing patients of AVN talus depending on identified disease factors such as early or late presentation, extent of bone involvement, bone collapse, and presence or absence of arthritis. Early talar AVN seems best treated with protected weight bearing and possibly in combination with extracorporeal shock wave therapy. If that fails, core decompression can be considered. Arthrodesis should be saved as a salvage procedure in late cases with arthritis and collapse, and a tibiotalocalcaneal fusion with bone grafting may be needed in cases of significant bone loss. Role of vascularized bone grafting is still not defined clearly and needs further investigation. Future prospective, randomized studies are necessary to guide the conservative and surgical management of talar AVN.

Management Options in Avascular Necrosis of Talus

PubMed Central

Dhillon, Mandeep S; Rana, Balvinder; Panda, Inayat; Patel, Sandeep; Kumar, Prasoon

2018-01-01

Avascular necrosis (AVN) of the talus can be a cause of significant disability and is a difficult problem to treat. The most common cause is a fracture of the talus. We have done a systematic review of the literature with the following aims: (1) identify and summarize the available evidence in literature for the treatment of talar AVN, (2) define the usefulness of radiological Hawkins sign and magnetic resonance imaging in early diagnosis, and (3) provide patient management guidelines. We searched MEDLINE and PUBMED using keywords and MESH terminology. The articles' abstracts were read by two of the authors. Forty-one studies met the inclusion criteria of the 335 abstracts screened. The interventions of interest included hindfoot fusion, conservative measures, bone grafting, vascularized bone graft, core decompression, and talar replacement. All studies were of Level IV evidence. We looked to identify the study quality, imprecise and sparse data, reporting bias, and the quality of evidence. Based on the analysis of available literature, we make certain recommendations for managing patients of AVN talus depending on identified disease factors such as early or late presentation, extent of bone involvement, bone collapse, and presence or absence of arthritis. Early talar AVN seems best treated with protected weight bearing and possibly in combination with extracorporeal shock wave therapy. If that fails, core decompression can be considered. Arthrodesis should be saved as a salvage procedure in late cases with arthritis and collapse, and a tibiotalocalcaneal fusion with bone grafting may be needed in cases of significant bone loss. Role of vascularized bone grafting is still not defined clearly and needs further investigation. Future prospective, randomized studies are necessary to guide the conservative and surgical management of talar AVN. PMID:29887631

Long-term Clinical Results after Iloprost Treatment for Bone Marrow Edema and Avascular Necrosis

PubMed Central

Claßen, Tim; Becker, Antonia; Landgraeber, Stefan; Haversath, Marcel; Li, Xinning; Zilkens, Christoph; Krauspe, Rüdiger; Jäger, Marcus

2016-01-01

The treatments of avascular osteonecrosis (AVN) include both conservative and surgical methods which are dependent on the stage and progression of the disease. The vasoactive-prostaglandin-analogue iloprost (PGI2) has been utilized in several areas of medicine and recently has been used for the treatment of AVN. A total of 108 patients with 136 osteonecrosis of different joints, etiology and severity were treated with iloprost. The mean follow-up was 49.71 months: range 15-96 months, and outcome measurements recorded regarding subjective complaints, visual analog scale (pain), function and survival. The outcome scores used include the Harris Hip Score, Knee Society score, Foot and Ankle Survey, visual analogue scale (VAS) and a separate questionnaire. The location and etiology of AVN in our study demonstrated the typical pattern. All of the observed side effects of the therapy were minor and completely reversible. Most of patients (74.8%) showed a significant improvement of subjective complaints and decrease in VAS pain scores after the treatment with iloprost. However, 20% of the treated joints with the stadium Association for Research on Osseous Circulation (ARCO) grade 2, 71% with ARCO 3 and 100% with ARCO 4 underwent subsequent total joint replacement. The medical treatment of bone marrow edema or avascular osteonecrosis by Iloprost provides an safe and effective alternative strategy in the management of AVN presenting in the early stages (ARCO 1 or 2). For more advanced stages (ARCO 3 or 4), surgical intervention should be prioritized. PMID:27114807

F-18 fluoride positron emission tomography/computed tomography in the diagnosis of avascular necrosis of the femoral head: Comparison with magnetic resonance imaging

PubMed Central

Gayana, Shankaramurthy; Bhattacharya, Anish; Sen, Ramesh Kumar; Singh, Paramjeet; Prakash, Mahesh; Mittal, Bhagwant Rai

2016-01-01

Objective: Femoral head avascular necrosis (FHAVN) is one of the increasingly common causes of musculoskeletal disability and poses a major diagnostic and therapeutic challenge. Although radiography, scintigraphy, computed tomography (CT), and magnetic resonance imaging (MRI) have been widely used in the diagnosis of FHAVN, positron emission tomography (PET) has recently been evaluated to assess vascularity of the femoral head. In this study, the authors compared F-18 fluoride PET/CT with MRI in the initial diagnosis of FHAVN. Patients and Methods: We prospectively studied 51 consecutive patients with a high clinical suspicion of FHAVN. All patients underwent MRI and F-18 fluoride PET/CT, the time interval between the two scans being 4–10 (mean 8) days. Two nuclear medicine physicians blinded to the MRI report read the PET/CT scans. Clinical assessment was also done. Final diagnoses were made by surgical pathology or clinical and radiologic follow-up. Results: A final diagnosis of avascular necrosis (AVN) was made in 40 patients. MRI was 96.5% sensitive, 100% specific, and 98.03% accurate while PET/CT was 100% sensitive, specific, and accurate in diagnosing FHAVN. The agreement between the two imaging modalities for the diagnosis of AVN was 96.07%. Conclusion: F-18 fluoride PET/CT showed good agreement with MRI in the initial diagnosis of FHAVN and can be better than MRI in detecting early disease. PMID:26917886

Association between open or closed reduction and avascular necrosis in developmental dysplasia of the hip

PubMed Central

Wang, Ya-Jie; Yang, Fan; Wu, Qi-Jun; Pan, Shi-Nong; Li, Lian-Yong

2016-01-01

Abstract Background: The risk of avascular necrosis of the femoral head (AVN) after treatment of developmental dysplasia of the hip is associated with the method of reduction. Some authors have suggested that open reduction is a risk factor for AVN; however, this is controversial. To our knowledge, a quantitative comparison of the incidence of AVN between closed and open reduction has not been conducted. Methods: Published studies were identified by searching PubMed, EMBASE, and the Cochrane Library up to May, 2015, focusing on the incidence of AVN after closed or open reduction for developmental dysplasia of the hip in children aged <3 years. Patients were age-matched who were treated by either closed or open reduction, but without pelvic or femoral osteotomy. Two authors independently assessed eligibility and abstracted data. Discrepancies were discussed and resolved by consensus. We pooled the odds ratios (ORs) and 95% confidence intervals (95%CIs) from individual studies using a random-effects model and evaluated heterogeneity and publication bias. Results: Nine retrospective studies were included in this analysis. The pooled OR for comparing open reduction with closed reduction for all grades of AVN was 2.26 (95%CI = 1.21–4.22), with moderate heterogeneity (I2 = 44.7%, P = 0.107). The pooled OR for grades II to IV AVN was 2.46 (95%CI = 0.93–6.51), with high heterogeneity (I2 = 69.6%, P = 0.003). A significant association was also found for the further surgery between open and closed reduction, with a pooled OR of 0.30 (95%CI = 0.15–0.60) and moderate heterogeneity (I2 = 46.4%, P = 0.133). No evidence of publication bias or significant heterogeneity between subgroups was detected by meta-regression analyses. Conclusion: Findings from this meta-analysis suggest that open reduction is a risk factor for the development of AVN compared with closed treatment. Future studies are warranted to investigate how open reduction combined with pelvis and/or femoral osteotomy affects the incidence of AVN. PMID:27442664

Association between open or closed reduction and avascular necrosis in developmental dysplasia of the hip: A PRISMA-compliant meta-analysis of observational studies.

PubMed

Wang, Ya-Jie; Yang, Fan; Wu, Qi-Jun; Pan, Shi-Nong; Li, Lian-Yong

2016-07-01

The risk of avascular necrosis of the femoral head (AVN) after treatment of developmental dysplasia of the hip is associated with the method of reduction. Some authors have suggested that open reduction is a risk factor for AVN; however, this is controversial. To our knowledge, a quantitative comparison of the incidence of AVN between closed and open reduction has not been conducted. Published studies were identified by searching PubMed, EMBASE, and the Cochrane Library up to May, 2015, focusing on the incidence of AVN after closed or open reduction for developmental dysplasia of the hip in children aged <3 years. Patients were age-matched who were treated by either closed or open reduction, but without pelvic or femoral osteotomy. Two authors independently assessed eligibility and abstracted data. Discrepancies were discussed and resolved by consensus. We pooled the odds ratios (ORs) and 95% confidence intervals (95%CIs) from individual studies using a random-effects model and evaluated heterogeneity and publication bias. Nine retrospective studies were included in this analysis. The pooled OR for comparing open reduction with closed reduction for all grades of AVN was 2.26 (95%CI = 1.21-4.22), with moderate heterogeneity (I = 44.7%, P = 0.107). The pooled OR for grades II to IV AVN was 2.46 (95%CI = 0.93-6.51), with high heterogeneity (I = 69.6%, P = 0.003). A significant association was also found for the further surgery between open and closed reduction, with a pooled OR of 0.30 (95%CI = 0.15-0.60) and moderate heterogeneity (I = 46.4%, P = 0.133). No evidence of publication bias or significant heterogeneity between subgroups was detected by meta-regression analyses. Findings from this meta-analysis suggest that open reduction is a risk factor for the development of AVN compared with closed treatment. Future studies are warranted to investigate how open reduction combined with pelvis and/or femoral osteotomy affects the incidence of AVN.

Shoulder Arthroplasty for Humeral Head Avascular Necrosis Is Associated With Increased Postoperative Complications.

PubMed

Burrus, M Tyrrell; Cancienne, Jourdan M; Boatright, Jeffrey D; Yang, Scott; Brockmeier, Stephen F; Werner, Brian C

2018-02-01

Humeral head avascular necrosis (AVN) of differing etiologies may lead to shoulder arthroplasty due to subchondral bone collapse and deformity of the articular surface. There have been no large studies evaluating the complications for these patients after they undergo total shoulder arthroplasty (TSA). The first objective of this study is to evaluate the complication rate after TSA in patients with humeral head AVN. The secondary objective is to compare the complication rates among the different etiologies of the AVN. Patients who underwent TSA were identified in the PearlDiver database using ICD-9 codes. Patients who underwent shoulder arthroplasty for humeral head AVN were identified using ICD-9 codes and were subclassified according to AVN etiology (posttraumatic, alcohol use, chronic steroid use, and idiopathic). Complications evaluated included postoperative infection within 6 months, dislocation within 1 year, revision shoulder arthroplasty up to 8 years postoperatively, shoulder stiffness within 1 year, and periprosthetic fracture within 1 year and systemic complications within 3 months. Postoperative complication rates were compared to controls. The study cohorts included 4129 TSA patients with AVN with 141,778 control TSA patients. Patients with posttraumatic AVN were significantly more likely to have a postoperative infection (OR 2.47, P  < 0.001), dislocation (OR 1.45, P  = 0.029), revision surgery (OR 1.53, P  = 0.001), stiffness (OR 1.24, P  = 0.042), and systemic complication (OR 1.49, P  < 0.001). Steroid-associated AVN was associated with a significantly increased risk for a postoperative infection (OR 1.72, P  = 0.004), revision surgery (OR 1.33, P  = 0.040), fracture (OR 2.76, P  = 0.002), and systemic complication (OR 1.59, P  < 0.001). Idiopathic and alcohol-associated AVN were not significantly associated with any of the postoperative evaluated complications. TSA in patients with humeral head AVN is associated with significantly increased rates of numerous postoperative complications compared to patients without a diagnosis of AVN, including infection, dislocation, revision arthroplasty, stiffness, periprosthetic fracture, and medical complications. Specifically, AVN due to steroid use or from a posttraumatic cause appears to be associated with the statistically highest rates of postoperative TSA complications. Given these findings, orthopedic surgeons should be increasingly aware of this association, which should influence the shared decision-making process of undergoing TSA in patients with humeral head AVN.

Risk factors and impact of orthopaedic monitoring on the outcome of avascular necrosis of the femoral head in adults with sickle cell disease: 215 patients case study with control group.

PubMed

Mukisi-Mukaza, M; Saint Martin, C; Etienne-Julan, M; Donkerwolcke, M; Burny, M E; Burny, F

2011-12-01

Sickle cell disease is a public health problem. The WHO has recommended that global management be implemented to reduce mortality and morbidity. Since no comprehensive care programme for bone and joint complications exists, the Caribbean Sickle Cell Disease Center added orthopaedic consultation to screen for and monitor these complications in 1992. Comprehensive medical and surgical care of patients with sickle cell disease will reduce the complications and disability associated with this disease. Two populations were compared to evaluate the impact of comprehensive disease management on the occurrence of avascular necrosis (AVN) of the femoral head (femoral head AVN). The case-control series, [E-1994], included 115 patients (58 SS and 57 S) without orthopaedic monitoring and was evaluated retrospectively. The other patient series, [E-2008], included 215 patients (94 SS and 121 SC) with systematic orthopaedic care and was followed prospectively. Age, gender, duration of follow-up, haemoglobin levels, genotype, pain before treatment, associated humerus AVN and leg ulcers were analysed. Femoral head AVN occurred in young adult patients (35.3 ± 4 years for [E-1994] and 29 ± 3.4 years for [E-2008]). Only elevated haemoglobin levels were associated with the occurrence of femoral head AVN, which suggests that increased blood viscosity contributes to the condition ([E-1994], P<0.0001; [E-2008], P=0.001). Treatment in [E-2008] patients reduced the number of femoral head AVN cases from 36.5% in [E-1994] to 14.4% in [E-2008] (P<0.0001). The prevention and management of femoral head AVN must include medical treatment of the disease to reduce the occurrence of painful vaso-occlusive crises, which are known to trigger femoral head AVN. The effectiveness of this programme hinged on identifying risk factors and using simple approaches (hydration, pain medication, rest and crutches) to manage painful joint crises before femoral head AVN appeared. These approaches could be implemented in disadvantaged countries where sickle cell disease is prevalent. By knowing the risk factors, symptomatic patients who are at risk for femoral head AVN can be identified and additional evaluations can be performed early on in cases of hip pain. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

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

PubMed

Ciapetti, Gabriela; Granchi, Donatella; Fotia, Caterina; Savarino, Lucia; Dallari, Dante; Del Piccolo, Nicola; Donati, Davide Maria; Baldini, Nicola

2016-09-01

Avascular necrosis of the femoral head (AVN) occurs as common result of various conditions or develops as a primary entity, with a high freqency in young adults. Because of its tendency toward osteoarthritis requiring total hip arthroplasty, alternative treatments are being advocated, including cell therapy with mesenchymal stromal cells (MSCs). Because osteonecrotic bone is a severely hypoxic tissue, with a 1-3% oxygen tension, the survival and function of multipotent cells is questionable. In this study, the proliferative, immunophenotypic and osteogenic properties of bone marrow (BM)-derived MSCs from a clinical series of patients with AVN were evaluated under in vitro conditions mimicking the hypoxic milieu of AVN to verify the rationale for cell therapy. MSCs retrieved from the iliac crest (BM-MSC) were isolated, expanded and induced to osteogenic differentiation under a 2% pO2 atmosphere (hypoxia) in comparison with the standard 21% pO2 (normoxia) that is routinely used in cell culture assays. Both proliferation and colony-forming ability were significantly enhanced in hypoxia-exposed BM-MSCs compared with BM-MSCs under normoxia. The expression of bone-related genes, including alkaline phosphatase, Type I collagen, and osteocalcin was significantly increased under hypoxia. Moreover, mineral deposition after osteogenic induction was not hampered, but in some cases even enhanced under low oxygen tension. These findings support autologous cell therapy as an effective treatment to stimulate bone healing in the hypoxic microenvironment of AVN. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Regenerative therapies increase survivorship of avascular necrosis of the femoral head: a systematic review and meta-analysis.

PubMed

Andriolo, Luca; Merli, Giulia; Tobar, Carlos; Altamura, Sante Alessandro; Kon, Elizaveta; Filardo, Giuseppe

2018-02-06

The aim of this study was to document the available evidence on the use of regenerative techniques for the treatment of femoral head osteonecrosis (or avascular necrosis of femoral head, AVN) and to understand their benefit compared to core decompression (CD) alone in avoiding failure and the need for total hip replacement (THR). The search was conducted on three medical electronic databases according to PRISMA guidelines. The studies reporting number and timing of failures were included in a meta-analysis calculating cumulative survivorship with a Kaplan-Mayer curve. Moreover, the results on failures in treatment groups reported in RCT were compared with those documented in control groups, in order to understand the benefit of biological therapies compared to CD for the treatment of AVN. Forty-eight studies were included in this systematic review, reporting results of different types of regenerative techniques: mesenchymal stem cell implantation in the osteonecrotic area, intra-arterial infiltration with mesenchymal stem cells, implantation of bioactive molecules, or platelet-rich plasma. Overall, reported results were good, with a cumulative survivorship of 80% after ten year follow-up, and better results when regenerative treatments were combined to CD compared to CD alone (89.9% vs 70.6%, p < 0.0001). Regenerative therapies offer good clinical results for the treatment of AVN. The combination of CD with regenerative techniques provides a significant improvement in terms of survivorship over time compared with CD alone. Further studies are needed to identify the best procedure and the most suitable patients to benefit from regenerative treatments for AVN.

Perthes' disease or late avascular necrosis after developmental dislocation of the hip? 10 children followed for 6-35 years.

PubMed

Koczewski, P; Napiontek, M

2001-08-01

We studied 10 patients treated because of late avascular necrosis (AVN) mimicking Legg-Calvé-Perthes' disease (LCPD) after developmental dislocation of the hip (DDH). DDH was recognized late at an average age of 5.4 months and in all children it was treated without surgery. In 4 children, the treatment was complicated by mild AVN of the femoral head, which had disappeared before 3 years of age. The first clinical signs of LCPD were noted at a mean age of 5.8 years. They all had Catterall's type III or IV of LCPD. The course was typical of LCPD. 8 children were operated on at mean age of 7.4 (5-12) years. In 7 of them, subtrochanteric derotation-varisation osteotomy of the femur with shortening combined mainly with Dega's pelvic osteotomy was done. The operative treatment resulted in a concentric position of the femoral head and good coverage of the acetabulum. Follow-ups were done at 10 (6-35) years. Shortened femoral neck and trochanteric overgrowth occurred in 4 operated hips. According to the Stulberg classification, 2 hips were classified as type I, 1 as I/II, 5 as II/I as II/III and 1 as IV. We conclude that LCPD mimicking late AVN can occur in hips treated because of developmental dislocation.

Effectiveness of Lower Energy Density Extracorporeal Shock Wave Therapy in the Early Stage of Avascular Necrosis of the Femoral Head.

PubMed

Han, Yong; Lee, June-Kyung; Lee, Bong-Yeon; Kee, Hoi-Sung; Jung, Kwang-Ik; Yoon, Seo-Ra

2016-10-01

To evaluate the effectiveness of lower energy flux density (EFD) extracorporeal shock wave therapy (ESWT) in the early stage of avascular necrosis (AVN) of the femoral head. Nineteen patients and 30 hips were enrolled. All subjects received 4 weekly sessions of ESWT, at different energy levels; group A (n=15; 1,000 shocks/session, EFD per shock 0.12 mJ/mm 2 ) and group B (n=15; 1,000 shocks/session, EFD per shock 0.32 mJ/mm 2 ). We measured pain by using the visual analog scale (VAS), and disability by using the Harris hip score, Hip dysfunction and Osteoarthritis Outcome Score (HOOS), and the Western Ontario and McMaster University Osteoarthritis Index (WOMAC). To determine the effect of the lower EFD ESWT, we assessed the VAS, Harris hip score, HOOS, WOMAC of the subjects before and at 1, 3, and 6 months. In both groups, the VAS, Harris hip score, HOOS, and WOMAC scores improved over time (p<0.05). Lower EFD ESWT may be an effective method to improve the function and to relieve pain in the early stage of AVN.

Managing AVN following internal fixation: treatment options and clinical results.

PubMed

Hoskinson, Simon; Morison, Zachary; Shahrokhi, Shahram; Schemitsch, Emil H

2015-03-01

Avascular necrosis (AVN) after internal fixation of intracapsular hip fractures is a progressive multifactorial disease that ultimately results in local ischemia with ensuing osteocyte necrosis and structural compromise. This disease can cause significant clinical morbidity and affects patients of any age, including young and active patients. Effective treatment of this condition among young adults is challenging due to their high functional demands. The aim of managing AVN is to relieve pain, preserve range of movement and improve function. Treatment methods vary depending on the stage of the disease and can be broadly categorised into two options, hip preserving surgery and hip arthroplasty. Although, hip preserving techniques are attractive in the young adult, they may alter the morphology of the proximal femur and make subsequent arthroplasty more challenging. Conversely, arthroplasty in the young adult may require repeat revision procedures throughout the patient's life. Current evidence suggests that modifications of prevailing treatments, in addition to new technologies, have led to the development of management strategies that may be able to alter the course of femoral head osteonecrosis. This review aims to summarise the options available for treatment of AVN in the young adult and review the clinical results. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Fracture Type and Injury-to-Surgery Interval as Risk Factors for Avascular Necrosis of the Femoral Head after Internal Fixation of Intracapsular Femoral Neck Fracture].

PubMed

Popelka, O; Skála-Rosenbaum, J; Bartoška, R; Waldauf, P; Krbec, M; Džupa, V

2015-01-01

The aim of the study was to investigate the occurrence of avascular necrosis (AVN) of the femoral head following the osteosynthesis of intracapsular fracture of the femoral neck in relation to the time interval between injury and surgery and the type of fracture. The data of patients with intracapsular fractures of the femoral neck surgically treated in the period from 2001 to 2011 were reviewed. Of 1555 patients treated for this fracture, 125 (7%) underwent osteosynthesis. The evaluated group included 115 patients who came for examination at one-year follow-up. There were 59 (52%) women and 56 (48%) men. Dynamic hip screw (DHS) osteosynthesis with an anti-rotation screw was performed in 103 patients and lag-screw osteosynthesis involving three parallel cannulated cancellous screws was employed in 12 patients. The patients were allocated to groups according to the injury-to-surgery interval and to sub-groups on the basis of the Garden classification of femoral fracture stage. In the group of 58 patients treated within 6 h of injury, AVN developed in 10 (17%). When the type of fracture was considered, 4% of the non-displaced fractures and 30% of the displaced fractures developed AVN. The patients with Garden stage I and II (non-displaced) fractures treated within 6 h of injury had a significantly lower risk of AVN development than those with Garden stage III or IV (displaced) fractures. The group treated between 6 and 24 post-injury hours comprised 21 patients, of whom four (19%) had AVN. In non-displaced and displaced fracture sub-groups, 25% of the patients in the former and 16% in the latter had AVN. The stage of displacement had no effect on AVN development. The two groups together (patients treated by 24 h) had a significantly lower AVN incidence than the patients treated after 24 h (p = 0.0025). In this group of 36 patients, 16 had AVN (44%) and the fracture stage made no significant difference (p = 0.6985; nondisplacement sub-group, 41%; displacement sub-group, 55%). The study showed a significantly lower AVN occurrence in the patients surgically treated within 24 h of injury. In the patients treated within 6 h of injury, AVN incidence was significantly lower in the patients with non-displaced fractures, as compared with those who had displaced fractures. This was not true for the two patient groups treated later (6-24 and later than 24 h) in which the differences between AVN development after non-displaced fractures and that after displaced fractures were similar.

Evidence for Using Alendronate to Treat Adult Avascular Necrosis of the Femoral Head: A Systematic Review

PubMed Central

Luo, Ru-Bin; Lin, Tiao; Zhong, Hui-Ming; Yan, Shi-Gui; Wang, Jian-An

2014-01-01

Osteonecrosis or avascular osteonecrosis (AVN) of the femoral head is a devastating multifactorial disease that affects 20 000 persons each year in the United States. The purpose of this systematic review was to determine the efficacy and safety of alendronate for adult AVN during short- and long-term follow-up. Electronic databases were searched for randomized or nonrandomized clinical trials, cohort, case-control studies, and series of cases in which alendronate was used for treatment of adult AVN of the femoral head. Relevant articles with adequate data on reduction of pain, improvement of articular function, slowing of bone collapse progression, or need for total hip arthroplasty (THA) were included after applying inclusion and exclusion criteria. Eight articles involving 788 hips with evidence level 1b to 3b were included in this systematic review. Most studies suggested a positive short-term efficacy of alendronate treatment in reducing pain, improving articular function, slowing of bone collapse progression, and delaying the need for THA for adult AVN patients. The favorable long-term results were also presented in those treated patients after 10-year follow-up. In addition, there were no severe adverse effects associated with alendronate treatment observed during short- and long-term follow-up, and most of the included studies suggested use of alendronate in early AVN with small necrotic lesion to achieve better outcomes. The findings support consideration of alendronate use for adult AVN, particularly with early stage and small necrotic size. The lack of large-scale, randomized, and double-blind studies justifies new studies to demonstrate the detailed indication and the optimized strategy of alendronate treatment. Level of evidence: Level 3a. PMID:25424061

Comparison of Outcomes of Total Hip Arthroplasty between Patients with Ankylosing Spondylitis and Avascular Necrosis of the Femoral Head.

PubMed

Lee, Sun-Ho; Lee, Gun-Woo; Seol, Young-Jun; Park, Kyung-Soon; Yoon, Taek-Rim

2017-09-01

The objective of this study was to compare clinical and radiological outcomes of total hip arthroplasty (THA) between ankylosing spondylitis (AS) of the hip joint and avascular necrosis (AVN) of the femoral head. Thirty patients (30 hips) underwent cementless THA for AS between 2003 and 2012. They were compared to 30 patients (30 hips) who underwent the same procedure for AVN of the femoral head. Each group was matched for age and gender, and both groups had similar preoperative demographic characteristics. All cases were followed for minimum 4 postoperative years. Clinical evaluation was based on operation time, intraoperative blood loss, quantity of postoperative drainage, Harris Hip Score (HHS), and range of motion (ROM). Radiological results were evaluated by acetabular cup anteversion and inclination, femoral stem orientation, pre- and postoperative leg length discrepancy, and postoperative complications. The operation time was significantly longer in the AS group (120.2 ± 26.2 min) than in the AVN group (79.5 ± 11.1 min). The volume of postoperative drainage was significantly greater in the AS group (764.5 ± 355.4 mL vs. 510.5 ± 195.6 mL). Preoperative HHS was lower in the AS group (55.6 ± 13.8 vs. 59.2 ± 2.8). Similarly, postoperative HHS was significantly lower in the AS group (92.8 ± 2.7 vs. 97.4 ± 2.6). The arc of ROM was improved from 146.5° ± 13.2° preoperatively to 254.7° ± 17.2° postoperatively in the AS group and from 182.6° ± 15.5° to 260.4° ± 13.7° in the AVN group. Implant position and postoperative leg length discrepancy were not different between the groups. However, three cases of heterotopic ossification was observed in the AS group, whereas only 1 case was found in the AVN group. One deep infection and one aseptic stem loosening were found in the AS group, whereas none was observed in the AVN group. Cementless THA showed satisfactory clinical and radiological results in both groups, despite the longer operation time, larger blood loss volume, and lower HHS score of the AS group. Our findings suggest that cementless THA is an effective and reliable treatment for both AS and AVN.

Complex proximal humerus fractures: Hertel's criteria reliability to predict head necrosis.

PubMed

Campochiaro, G; Rebuzzi, M; Baudi, P; Catani, F

2015-09-01

The risk of post-traumatic humeral head avascular necrosis (AVN), regardless of the treatment, has a high reported incidence. In 2004, Hertel et al. stated that the most relevant predictors of ischemia after intracapsular fracture treated with osteosynthesis are the calcar length, medial hinge integrity and some specific fracture types. Based on Hertel's model, the purpose of this study is to evaluate both its reliability and weaknesses in our series of 267 fractures, assessing how the anatomical configuration of fracture, the quality of reduction and its maintenance were predictive of osteonecrosis development, and so to suggest a treatment choice algorithm. A retrospective study, level of evidence IV, was conducted to duly assess the radiographic features of 267 fractures treated from 2004 to 2010 following Hertel's criteria treated with open reduction and internal fixation by angular stability plates and screws. The average age was 65.2 years. The average follow-up was 28.3 ± 17.0 months. The percentage of AVN, the quality and maintenance of reduction obtained during surgery were evaluated. The AVN incidence was 3.7 %. No significant correlation with gender, age and fracture type was found. At the last follow-up X-ray, only 30 % presented all Hertel's good predictors in the AVN group, 4.7 % in the non-AVN group (p < 0.05). About quality of reduction in the AVN group, it was poor in 50 %; while in the non-AVN group, it was poor in 3.4 % (p < 0.05). Four patients with AVN were symptomatic, and three needed a second surgery. Hertel's criteria are important in the surgical planning, but they are not sufficient: an accurate evaluation of the calcar area fracture in three planes is required. All fractures involving calcar area should be studied with CT.

Risk factors of avascular necrosis of the femoral head and fixation failure in patients with valgus angulated femoral neck fractures over the age of 50 years.

PubMed

Song, Hyung Keun; Choi, Ho June; Yang, Kyu Hyun

2016-12-01

The aim of our study was to identify the risk factors for avascular necrosis of the femoral head (AVN) and fixation failure (FF) after screw osteosynthesis in patients with valgus angulated femoral neck fractures. We conducted a retrospective study of 308 patients (mean age, 72.5 years, range, 50-97 years), with a mean follow-up of 21.4 months (range, 12-64 months). The risk for failure in treatment (FIT) associated with patient- and fracture-related factors was evaluated by logistic regression analyses. FIT was identified in 32 cases (10.3%): 22 cases (7.1%) of AVN and 10 cases (3.2%) of FF. Initial valgus tilt>15° (p=0.023), posterior tilt>15° (p=0.012), and screw sliding distance (p=0.037) were significantly associated with FIT. FIT occurred in 7 patients (5.2%) with B1.2.1 fractures and 17 patients (48.6%) with B1.1.2 fractures (p<0.001). The odds of FIT were 17-fold higher in patients with initial valgus and posterior tilts>15° (B1.1.2) compared to patients with <15° of tilt in both planes (B1.2.1). The severity of initial deformity predicts AVN and FF in patients with valgus angulated femoral neck fractures. Patients with an initial valgus and posterior tilt>15° are reasonable candidates for primary arthroplasty due to high risk of FIT. Copyright © 2016 Elsevier Ltd. All rights reserved.

Total hip arthroplasty survival in femoral head avascular necrosis versus primary hip osteoarthritis: Case-control study with a mean 10-year follow-up after anatomical cementless metal-on-metal 28-mm replacement.

PubMed

Ancelin, D; Reina, N; Cavaignac, E; Delclaux, S; Chiron, P

2016-12-01

Total hip arthroplasty is the most widely used procedure to treat avascular necrosis (AVN) of the femoral head. Few studies have compared the outcomes of THA in femoral head AVN and primary hip osteoarthritis. Therefore we performed a case-control study to compare THA for femoral head AVN vs. primary hip osteoarthritis in terms of: (1) prosthesis survival, (2) complication rates, (3) functional outcomes and radiographic outcomes, (4) and to determine whether specific risk factors for THA failure exist in femoral head AVN. THA survival is similar in femoral head AVN and primary hip osteoarthritis. We compared two prospective cohorts of patients who underwent THA before 65 years of age, one composed of cases with femoral head AVN and the other of controls with primary hip osteoarthritis. In both cohorts, a cementless metal-on-metal prosthesis with a 28-mm cup and an anatomical stem was used. Exclusion criteria were THA with other types of prosthesis, posttraumatic AVN, and secondary osteoarthritis. With α set at 5%, to obtain 80% power, 246 patients were required in all. Prosthesis survival was assessed based on time to major revision (defined as replacement of at least one implant fixed to bone) and time to aseptic loosening. The other evaluation criteria were complications, Postel-Merle d'Aubigné (PMA) score, and the Engh and Agora Radiographic Assessment (ARA) scores for implant osseointegration. The study included 282 patients, 149 with AVN and 133 with osteoarthritis. Mean age was 47.8±10.2 years (range, 18.5-65) and mean follow-up was 11.4±2.8 years (range, 4.5-18.3 years). The 10-year survival rates were similar in the two groups: for major revision, AVN group, 92.5% (95% confidence interval [95% CI], 90.2-94.8) and osteoarthritis group, 95.3% (95% CI, 92.9-97.7); for aseptic loosening, AVN group, 98.6% (95% CI, 97.6-98.6) and osteoarthritis, 99.2% (95% CI, 98.4-100). The AVN group had higher numbers of revision for any reason (19 vs. 6, P=0.018) and for dislocation (8 vs. 1, P=0.031). Mean PMA scores at last follow-up were comparable in the AVN group (17.65±1.27 [range, 10-18]) and osteoarthritis group (17.59±1.32 [range, 14-18]) (P=0.139). Osseointegration was also similar in the two groups: global Engh score, 26.51±1.81 (range, 14-27) for AVN and 26.84±0.91 (range, 19.5-27) for osteoarthritis (P=0.065); femoral ARA score, 5.83±0.46 (range, 3-6) for AVN and 5.90±0.42 (range, 3-6) for osteoarthritis (P=0.064); and cup ARA score, 5.74±0.67 (range, 3-6) for AVN and 5.78±0.66 (range, 3-6) for osteoarthritis (P=0.344). Survival in this study was good and consistent with recent data on AVN, with no difference between AVN and osteoarthritis. Revisions for any cause or for dislocation were more common after THA for AVN. Functional outcomes were similar in the AVN and osteoarthritis groups. An anatomical cementless prosthesis combined with metal-on-metal 28-mm bearing provides durable good outcomes. III, non-randomized comparison of two prospective cohorts. Published by Elsevier Masson SAS.

Bone marrow oedema on MR imaging indicates ARCO stage 3 disease in patients with AVN of the femoral head.

PubMed

Meier, Reinhard; Kraus, Tobias M; Schaeffeler, Christoph; Torka, Sebastian; Schlitter, Anna Melissa; Specht, Katja; Haller, Bernhard; Waldt, Simone; Rechl, Hans; Rummeny, Ernst J; Woertler, Klaus

2014-09-01

To test the hypothesis that bone marrow oedema (BME) observed on MRI in patients with avascular necrosis (AVN) of the femoral head represents an indicator of subchondral fracture. Thirty-seven symptomatic hips of 27 consecutive patients (53% women, mean age 49.2) with AVN of the femoral head and associated BME on magnetic resonance (MR) imaging were included. MR findings were correlated with computed tomography (CT) of the hip and confirmed by histopathological examination of the resected femoral head. Imaging studies were analysed by two radiologists with use of the ARCO classification. On MR imaging a fracture line could be identified in 19/37 (51%) cases, which were classified as ARCO stage 3 (n = 15) and stage 4 (n = 4). The remaining 18/37 (49%) cases were classified as ARCO stage 2. However, in all 37/37 (100%) cases a subchondral fracture was identified on CT, indicating ARCO stage 3/4 disease. The extent of subchondral fractures and the femoral head collapse was graded higher on CT as compared to MRI (P < 0.05). Histopathological analysis confirmed bone necrosis and subchondral fractures. In patients with AVN, BME of the femoral head represents a secondary sign of subchondral fracture and thus indicates ARCO stage 3 disease. BME on MRI in AVN of femoral head indicates a subchondral fracture. BME in AVN of the femoral head represents ARCO stage 3/4 disease. CT identifies subchondral fractures and femoral head collapse better than MR imaging. This knowledge helps to avoid understaging and to trigger adequate treatment.

Long-term outcome following medial open reduction in developmental dysplasia of the hip: a retrospective cohort study.

PubMed

Gardner, Richard O E; Bradley, Catharine S; Sharma, Om P; Feng, Lin; Shin, Michelle EyunJung; Kelley, Simon P; Wedge, J H

2016-06-01

Avascular necrosis (AVN) is a serious complication of treatment for developmental dysplasia of the hip. There is ongoing controversy regarding AVN and its influence on hip development following medial open reduction (MOR). The aim of our study was to (1) determine the long-term prevalence of AVN following MOR, (2) evaluate hip development after MOR, and (3) identify predictors of AVN and radiographic outcome at skeletal maturity after MOR. A retrospective cohort analysis of 60 patients (70 hips) who underwent MOR with a mean follow-up of 10.83 years (5.23-16.74) was conducted. AVN was recorded according to Bucholz and Ogden classification and radiographic outcome based on Severin grading. AVN and hip morphology related to length of follow-up were evaluated. Chi-squared and t-tests were used to identify relationships between AVN and other variables. Logistic regression was used to assess predictors of AVN and Severin outcome. The rate of clinically significant AVN (types 2-4) following MOR was 32.9 % with type 2 accounting for 82.6 % of these cases. While early acetabular development was satisfactory, long-term outcome was unsatisfactory in 26 % of cases with AVN (vs 8.7 % of cases without AVN). A higher rate of AVN was identified when hips were immobilized in ≥60° of abduction postoperatively. A higher rate of poor Severin outcome was identified in hips with AVN. Our findings suggest that there is a high rate of AVN and unsatisfactory long-term outcome following MOR. AVN remains a significant concern following MOR surgery for developmental dysplasia of the hip that may not be apparent until long-term evaluation.

Management of non-traumatic avascular necrosis of the femoral head-a comparative analysis of the outcome of multiple small diameter drilling and core decompression with fibular grafting.

PubMed

Mohanty, S P; Singh, K A; Kundangar, R; Shankar, V

2017-04-01

The purpose of this study was to compare the clinical and radiological outcomes of multiple small diameter drilling and core decompression with fibular strut grafting in the management of non-traumatic avascular necrosis (AVN) of the femoral head. Outcomes of patients with AVN treated by multiple small diameter drilling (group 1) were compared retrospectively with patients treated by core decompression and fibular grafting (group 2). Harris hip score (HHS) was used to assess the clinical status pre- and postoperatively. Modified Ficat and Arlet classification was used to assess the radiological stage pre- and postoperatively. Forty-six patients (68 hips) were included in this study. Group 1 consisted of 33 hips, and group 2 consisted of 35 hips. In stages I and IIB, there was no statistically significant difference in the final HHS between the two groups. However, in stages IIA and III, hips in group 2 had a better final HHS (P < 0.05). In terms of radiographic progression, there was no statistical difference between hips in stages I, IIA and stage IIB. However, in stage III, hips belonging to group 2 had better results (P < 0.05). Kaplan-Meier survivorship analysis showed better outcome in group 2 in stage III (P < 0.05). Hips with AVN in the precollapse stage can be salvaged by core decompression with or without fibular grafting. Multiple small diameter drilling is relatively simple and carries less morbidity and hence preferred in stages I and II. However, in stage III disease, core decompression with fibular strut grafting gives better results.

Bipolar hip arthroplasty for avascular necrosis of femoral head in young adults

PubMed Central

Dudani, Baldev; Shyam, Ashok K; Arora, Pankush; Veigus, Arjun

2015-01-01

Background: Bipolar hip arthroplasty (BHA) is one of the options for treatment of avascular necrosis (AVN) of the femoral head. Acetabular erosion and groin pain are the most allowing for gross motion between the common complications. We propose that these complications are secondary to improper acetabular preparation allowing for motion between the BHA head and the acetabulum. Materials and Methods: The current study retrospectively evaluated patients’records from case files and also called them for clinical and radiological followup. 96 hips with AVN of the femoral head treated with BHA were included in the study. All patients were males with a mean age of 42 years (range 30-59 years). In all cases, the acetabulum was gently reamed till it became uniformly concentric to achieve tight fitting trial cup. Clinical followup using Harris hip score (HHS) and radiological study for cup migration were done at followup. Results: The mean followup was 7.52 years (range 4-16 years). The HHS significantly improved from a preoperative value of 39.3 (range, 54-30) to a postoperative value of 89.12 (range 74-96). According to HHS grades, the final outcome was excellent in 52 hips, good in 28 and fair in 16 hips. Hip and groin pain was reported in four hips (5%), but did not limit activity. Subsidence (less than 5 mm) of the femoral component was seen in 8 cases. Subgroup analysis showed patients with Ficat Stage 3 having better range of motion, but similar HHS as compared to Ficat Stage 4 patients. Conclusion: Bipolar hip arthroplasty (BHA) using tight fitting cup and acetabular reaming in AVN hip has a low incidence of groin pain, acetabular erosion and revision in midterm followup. Good outcome and mid term survival can be achieved irrespective of the Ficat Stage. PMID:26015634

Bone Marrow Aspirate Concentrate in Combination With Intravenous Iloprost Increases Bone Healing in Patients With Avascular Necrosis of the Femoral Head: A Matched Pair Analysis.

PubMed

Pilge, Hakan; Bittersohl, Bernd; Schneppendahl, Johannes; Hesper, Tobias; Zilkens, Christoph; Ruppert, Martin; Krauspe, Rüdiger; Jäger, Marcus

2016-11-17

With disease progression, avascular necrosis (AVN) of the femoral head may lead to a collapse of the articular surface. The exact pathophysiology of AVN remains unclear, although several conditions are known that can result in spontaneous cell death, leading to a reduction of trabecular bone and the development of AVN. Hip AVN treatment is stage-dependent in which two main stages of the disease can be distinguished: pre-collapse (ARCO 0-II) and post-collapse stage (ARCO III-IV, crescent sign). In the pre-collapse phase, core decompression (CD), with or without the addition of bone marrow ( e.g . bone marrow aspirate concentrate, BMAC) or bone graft, is a common treatment alternative. In the post-collapse phase, THA (total hip arthroplasty) must be performed in most of the patients. In addition to surgical treatment, the intravenous application of Iloprost has been shown to have a curative potential and analgesic effect. From October 2009 to October 2014, 49 patients with AVN (stages I-III) were treated with core decompression at our institution. All patients were divided into group A (CD + BMAC) and group B (CD alone). Of these patients, 20 were included in a matched pair analysis. The patients were matched to age, gender, ARCO-stage, Kerboul combined necrotic angle, the cause of AVN, and whether Iloprost-therapy was performed. The Merle d'Aubigné Score and the Kerboul combined necrotic angle in a-p and lateral radiographs were evaluated pre- and postoperatively. The primary endpoint was a total hip arthroplasty. In group A, two patients needed THA while in group B four patients were treated with THA. In group A, the Merle d'Aubigné Score improved from 13.5 (pre-operatively) to 15.3 (postoperatively). In group B there was no difference between the pre- (14.3) and postoperative (14.1) assessment. The mean of the Kerboul angle showed no difference in both groups compared pre- to postoperatively (group A: pre-op 212°, postop 220°, group B: pre-op 213, postop 222°). Regarding radiographic evaluation, the interobserver variability revealed a moderate agreement between two raters regarding the pre-(ICC 0.594) and postoperative analysis (ICC 0.604).This study demonstrates that CD in combination with the application of autologous bone marrow aspirate concentrate into the femoral head seems to be a safe and efficient treatment alternative in the early stages of AVN of the femoral head when compared to CD alone.

Is Disuse Osteopenia a Favorable Prognostic Sign After Femoral Neck Fracture?

PubMed

Ting, Beverlie L; Heng, Marilyn; Vrahas, Mark S; Rodriguez, Edward K; Harris, Mitchel B; Weaver, Michael J

2016-09-01

Avascular necrosis (AVN) of the femoral head is a devastating complication following fixation of femoral neck fractures in younger adults. In this study, we investigate the prognostic utility of disuse osteopenia. Retrospective study. Three academic Level 1 trauma centers. One hundred twenty patients younger than 60 years treated for a femoral neck fracture. N/A. The presence of sclerosis or osteopenia, compared to the contralateral femoral head, was measured 6 weeks from injury both subjectively and using a novel radiographic measure, the relative density ratio (RDR). The outcome measure was radiographic development of AVN. The presence of relative sclerosis was associated with AVN and overall treatment failure. Patients with subjective relative sclerosis had a 12.6 (95% confidence interval, 2.9-61.3; P < 0.001) times higher odds of developing AVN. Multiple logistic regression showed that for every 0.10 increase in the RDR, there was a 5.2 increase in the odds (95% confidence interval, 2.1-26.9; P = 0.009) of developing AVN. Patients with an RDR of ≥1.2 have an 80% probability of AVN, whereas those with an RDR ≤0.8 have a <1% probability of developing AVN. Disuse osteopenia detected on 6-week radiographs is a favorable prognostic sign following fixation of femoral neck fractures. Patients who have relative sclerosis of the femoral head at 6-week follow-up are at a higher risk of developing AVN. Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Efficacy of alendronate, a bisphosphonate, in the treatment of AVN of the hip. A prospective open-label study.

PubMed

Agarwala, S; Jain, D; Joshi, V R; Sule, A

2005-03-01

To study the efficacy of alendronate, in the treatment of avascular necrosis (AVN) of the hip. Sixty patients with AVN of the hip (100 hips with AVN) were studied. The follow-up period ranged from 3 months to 5 yr. The most common cause of AVN was steroids. Parameters studied were walking time, standing time, pain and disability on a visual analogue scale (VAS), range of motion of the hip, X-ray and MRI of the hip. All patients were treated with alendronate 10 mg/day (or 70 mg/week) along with 500-1000 mg of daily calcium and vitamin D supplements, and were advised to avoid weight-bearing. NSAIDs and analgesics were permitted as needed and were recorded. Forty-one patients (71 AVN hips) with AVN have been followed up for a minimum of 1 yr, 24 patients (42 AVN hips) for 2 yr and 21 patients (37 AVN hips) for more than 2 yr (average 37 month). Fourteen patients have been followed up for less than 1 yr (3-9 months). Significant reduction in pain and disability scores (P < 0.001) and significant increase in standing and walking time (P < 0.001) were observed. All hip movements improved at 1 yr (P value 0.000-0.009) with an insignificant decline after that (P > 0.001). Radiologically, the hips either stabilized in the same grade or progressed by one grade. MRI showed a decrease in marrow oedema in most cases at the 1-yr follow-up. Six patients (10 hips) required surgery and there were two (three hips) dropouts. The drug was well tolerated and there was a reduction in NSAID requirement. Alendronate reduces pain, improves function and retards AVN progression. Early surgical intervention can be avoided in most patients.

Diffusion-weighted magnetic resonance imaging of femoral head osteonecrosis in two groups of patients: Legg-Perthes-Calve and Avascular necrosis.

PubMed

Ozel, Betul Duran; Ozel, Deniz; Ozkan, Fuat; Halefoglu, Ahmet M

2016-03-01

The aim of this prospective study was to evaluate the value of diffusion-weighted magnetic resonance imaging (DW-MRI) in patients with osteonecrosis. Patients were divided into two subgroups as avascular necrosis (AVN) of femoral head for adult group and Legg-Calvé-Perthes (LCP) patients for children. Seventeen patients with femoral head AVN (mean age 42.3 years) and 17 patients with LCP (mean age 8.2 years) were included in this study. Diagnosis confirmed with clinical and other imaging procedures among the patients complaining hip pain. DW images were obtained using the single-shot echo planar sequence and had b values of 0, 500, 1000 s/mm(2). The apparent diffusion coefficient (ADC) values were measured from ADC maps in epiphysis of patients with AVN, both from metaphysis and epiphysis in patients with LCP, respectively. Mann-Whitney U test was used to compare ADC values. The mean ADC value of femoral heads (1.285 ± 0.204 × 10(-3) mm(2)/s) was increased in patients with AVN when compared to normal bone tissue (0.209 ± 0.214 × 10(-3) mm(2)/s) (p < 0.01). The mean ADC values (×10(-3) mm(2)/s) of both metaphysis (0.852 ± 0.293) and epiphysis (0.843 ± 0.332) were also increased in patients with LCP and differences were statistically significant (p < 0.01). As a result, osteonecrosis shows increased ADC values. But it is a controversial concept that DWI offers a valuable data to conventional MRI or not. However, as there are report states, there is a correlation between the stage of the disease with ADC values in the LCP disease. DWI is a fast, without-contrast administration technique and provides quantitative values additional to conventional MR techniques; we believe DWI may play an additional assistance to the diagnosis and treatment for LCP patients. Multicentric larger group studies may provide additional data to this issue.

The Frequency of AVN Following Reconstructive Hip Surgery in Children With Cerebral Palsy: A Systematic Review.

PubMed

Hesketh, Kim; Leveille, Lise; Mulpuri, Kishore

2016-03-01

Children with cerebral palsy (CP) undergoing reconstructive hip surgery are at risk for developing avascular necrosis (AVN). The purpose of this systematic review was to investigate the reported frequency of AVN, the amount and quality of literature available, and possibly identity risk factors for developing AVN following reconstructive surgery for hip displacement in children with CP. We performed a review of the literature using EMBASE and MEDLINE databases. Studies investigating the outcome of reconstructive hip surgery in patients with CP that identified the presence or absence of AVN were included. Study quality was assessed using the Methodological Index for Non-Randomized Studies and the Oxford Centre for Evidence-Based Medicine scale. Three hundred and ninety-nine articles were identified using our search strategy. Twenty-nine studies were included for data extraction after full-text review. The frequency of AVN ranged from 0% to 46% with an overall rate across studies of 7.5%. Presence of AVN was the primary outcome in 2 studies. The frequency of AVN in these studies was significantly higher than other studies at 37% and 46%. No statistically significant associations were found between age at surgery, severity of hip subluxation, length of follow-up, or type of surgery (combined varus derotation osteotomy and pelvic osteotomy vs. varus derotation osteotomy alone), and the rate of AVN. The majority of studies did not comment on methods used for determining diagnosis or severity of AVN and clinical significance was not well documented. Children with CP undergoing reconstructive hip surgery are at risk of developing AVN. Frequency and severity of this complication is poorly documented in the literature. On the basis of current evidence no significant risk factors were identified; however, it is not possible to draw firm conclusions about them. Incidence of AVN was higher in studies in which AVN was a primary outcome suggesting that the true frequency of AVN may be higher than is currently understood.

Expression profile of osteoprotegerin, RANK and RANKL genes in the femoral head of patients with avascular necrosis.

PubMed

Samara, Stavroula; Dailiana, Zoe; Chassanidis, Christos; Koromila, Theodora; Papatheodorou, Loukia; Malizos, Konstantinos N; Kollia, Panagoula

2014-02-01

Femoral head avascular necrosis (AVN) is a recalcitrant disease of the hip that leads to joint destruction. Osteoprotegerin (OPG), Receptor Activator of Nuclear Factor kappa-B (RANK) and RANK ligand (RANKL) regulate the balance between osteoclasts-osteoblasts. The expression of these genes affects the maturation and function of osteoblasts-osteoclasts and bone remodeling. In this study, we investigated the molecular pathways leading to AVN by studying the expression profile of OPG, RANK and RANKL genes. Quantitative Real Time-PCR was performed for evaluation of OPG, RANK and RANKL expression. Analysis was based on parallel evaluation of mRNA and protein levels in normal/necrotic sites of 42 osteonecrotic femoral heads (FHs). OPG and RANKL protein levels were estimated by western blotting. The OPG mRNA levels were higher (insignificantly) in the necrotic than the normal site (p > 0.05). Although the expression of RANK and RANKL was significantly lower than OPG in both sites, RANK and RANKL mRNA levels were higher in the necrotic part than the normal (p < 0.05). Protein levels of OPG and RANKL showed no remarkable divergence. Our results indicate that differential expression mechanisms for OPG, RANK and RANKL that could play an important role in the progress of bone remodeling in the necrotic area, disturbing bone homeostasis. This finding may have an effect on the resulting bone destruction and the subsequent collapse of the hip joint. Copyright © 2013. Published by Elsevier Inc.

Radiographic evaluation for AVN following distal metatarsal Stoffella bunion osteotomy.

PubMed

Klein, Christian; Zembsch, Alexander; Dorn, Ulrich

2009-01-01

Avascular necrosis of the metatarsal head, delayed bone healing and nonunion are complications that may occur after distal first metatarsal osteotomies. Intraoperative damage to the extraosseous blood supply, the location of the osteotomy and postoperative vasospasm have been cited as possible causes of such changes. We evaluated Stoffella's subcapital osteotomies which were performed at our department for the correction of moderate to severe hallux valgus deformities. Standardized radiographs of 300 feet, taken 6weeks, 3 months, and 6 months postoperatively and at the final followup were examined with regard to postoperative AVN or signs of delayed bone healing. Of 228 patients, 202 were women and 26 were men. The patients' mean age was 49 years, and the mean followup was 12 months. In 278 cases the radiographs revealed an unremarkable first metatarsal head. Seventeen cases showed diffuse or localized osteopenia or small cysts in the subchondral bone. These changes fully resolved on subsequent radiographs. The X-rays of two patients revealed progressive narrowing of the joint space, irregular contours on the surface of the joint and an abnormal bone structure. The patients subsequently developed a characteristic picture of avascular necrosis, in one case combined with nonunion. Three patients had delayed bone healing, but ultimately healed successfully. Ischemic changes in bone are known to occur after distal first metatarsal osteotomies. There is a very low incidence of postoperative perfusion problems after Stoffella;s technique, even with lateral soft tissue release.

The Tribology of Explanted Hip Resurfacings Following Early Fracture of the Femur.

PubMed

Lord, James K; Langton, David J; Nargol, Antoni V F; Meek, R M Dominic; Joyce, Thomas J

2015-10-15

A recognized issue related to metal-on-metal hip resurfacings is early fracture of the femur. Most theories regarding the cause of fracture relate to clinical factors but an engineering analysis of failed hip resurfacings has not previously been reported. The objective of this work was to determine the wear volumes and surface roughness values of a cohort of retrieved hip resurfacings which were removed due to early femoral fracture, infection and avascular necrosis (AVN). Nine resurfacing femoral heads were obtained following early fracture of the femur, a further five were retrieved due to infection and AVN. All fourteen were measured for volumetric wear using a co-ordinate measuring machine. Wear rates were then calculated and regions of the articulating surface were divided into "worn" and "unworn". Roughness values in these regions were measured using a non-contacting profilometer. The mean time to fracture was 3.7 months compared with 44.4 months for retrieval due to infection and AVN. Average wear rates in the early fracture heads were 64 times greater than those in the infection and AVN retrievals. Given the high wear rates of the early fracture components, such wear may be linked to an increased risk of femoral neck fracture.

Adverse Outcomes in Infantile Bilateral Developmental Dysplasia of the Hip.

PubMed

Morbi, Abigail H M; Carsi, Belen; Gorianinov, Vitalli; Clarke, Nicholas M P

2015-01-01

It is believed that bilateral developmental dysplasia of the hip (DDH) has poorer outcomes with higher rates of avascular necrosis (AVN) and reintervention, compared with unilateral DDH. However, there is limited evidence in the literature, with few studies looking specifically at bilateral cases. A retrospective review of 36 patients (72 hips) with >4 years of follow-up. Patient population included surgically treated DDH including late presentations and failures of conservative treatment. The dislocated hips underwent either simultaneous closed or 1 open and 1 closed, or sequential open reduction. AVN and secondary procedures were used as endpoints for analysis as well as clinical and radiologic outcomes. At the last follow-up, 33% of hips had radiologic signs of AVN. Those hips that had no ossific nucleus (ON) at the time of surgery had an odds ratio of developing AVN of 3.05 and a statistically significant association between the 2 variables, whereas open/closed or simultaneous/sequential reduction did not increase the risk for AVN. In addition, 45.8% of those hips required further surgery. The estimated odds ratio of needing additional surgery after simultaneous reduction was 4.04. Clinically, 79.2% of the hips were graded as McKay I, whereas radiologically only 38.8% were Severin I. The AVN rate in bilateral DDH treated surgically is greater than the rate noted in unilateral cases from the same institution undergoing identical protocols. There was no difference in AVN rates between simultaneous and sequential or between the first and second hip to be sequentially reduced. Presence of ON decreases the risk for AVN, suggesting that in bilateral cases, awaiting the appearance of the ON is an important tool to reduce the incidence of AVN. IV.

Surgical treatment of AVN of the fibular (lateral) sesamoid.

PubMed

Waizy, Hazibullah; Jäger, Marcus; Abbara-Czardybon, Mona; Schmidt, Troy G; Frank, Daniel

2008-02-01

Despite the fact that the hallucal sesamoids play a crucial role in forefoot mechanics, disorders resulting from pathology of these structures are often overlooked or misdiagnosed. Avascular necrosis (AVN) of the hallucal sesamoids is a rare condition that must be differentiated from other pathologies, such as fractures, pseudarthrosis or osteomyelitis. We report on two patients with AVN of the fibular (lateral) hallucal sesamoid (Morbus Renander). In both patients the necrotic part of the fibular sesamoid was excised surgically after failed conservative therapy. The followup was 29 and 26 months. The clinical and radiological results showed a complete relief of pain in both patients without any complications or forefoot deformities. Recent literature and own experiences support non-operative initial management including anti-inflammatory medications, shoe modification and temporary limited weight bearing. If symptoms persist, surgical treatment with excision of the necrotic part of the sesamoid may be an alternative. Consideration by the surgeon should be given to protecting the neurovascular bundle and reattaching intrinsic tendons and ligaments if necessary. Satisfying results can be achieved by surgical removal.

Timing of Surgical Reduction and Stabilization of Talus Fracture-Dislocations.

PubMed

Buckwalter V, Joseph A; Westermann, Robert; Mooers, Brian; Karam, Matthew; Wolf, Brian

Talus fractures with associated dislocations are rare but have high rates of complications, including avascular necrosis (AVN). Management of these injuries involves urgent surgical reduction and fixation, although there are no definitive data defining an operative time frame for preserving the blood supply and preventing complications. To determine the effect of time to surgical reduction of talus fractures and talus fracture-dislocations on rates of AVN and posttraumatic osteoarthritis (PTOA), we retrospectively reviewed talus fractures surgically managed at a level I trauma center during the 10-year period 2003 to 2013. Operative reports were obtained and reviewed, and 3 independent reviewers, using the Hawkins and AO/OTA (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association) systems, classified the injuries on plain radiographs. Analysis of AO/OTA 81 fractures with associated tibiotalar, subtalar, or talonavicular dislocations was performed. Primary outcomes were presence of AVN/PTOA and subsequent arthrodesis of tibiotalar or subtalar joints. We identified 106 surgically managed talus fractures. Rates of AVN/PTOA were 41% for all talus fractures and 50% for talus fracture-dislocations. Mean time to surgical reduction was not significant for development of AVN/PTOA for all talus fractures (P = .45) or talus fracture-dislocations (P = .29). There was no difference in age (P = .20), body mass index (P = .45), or polytrauma (P = .79) between patients who developed AVN and those who did not. Open fractures were significantly correlated with the development of AVN/PTOA (P = .009). Talar fracture-dislocations are devastating injuries with high rates of complications. Our data suggest there is no effect of time from injury to surgical reduction of talus fractures or talus fracture-dislocations on rates of AVN and PTOA.

Steroid-induced femoral head osteonecrosis in immune thrombocytopenia treatment with osteochondral autograft transplantation.

PubMed

Fotopoulos, Vasileios Ch; Mouzopoulos, George; Floros, Themistoklis; Tzurbakis, Matthaios

2015-09-01

Osteonecrosis of the femoral head is a devastating complication of steroid administration and has rarely been observed in the treatment of immune thrombocytopenia. The treatment of osteochondral defects in advanced stages of avascular necrosis (AVN), characterized by collapse of the subchondral bone, remains an unsolved burden in orthopedic surgery. In this report, we present a case of a 19-year-old female that was admitted in the Emergency Department with walking disability and painful hip joint movement due to steroid-induced femoral head osteonecrosis. Two years before she was diagnosed with immune thrombocytopenia, for which she received pulse steroid therapy with high dose of dexamethasone and underwent a splenectomy. This case report is the first to describe the use of osteochondral autograft transplantation as a treatment of steroid-induced AVN of the femoral head due to immune thrombocytopenia at the age of 19 years with very good clinical and radiological results 3 years postoperatively.

The prognostic value of the hawkins sign and diagnostic value of MRI after talar neck fractures.

PubMed

Chen, Hao; Liu, Wenzhou; Deng, Lianfu; Song, Weidong

2014-12-01

The early diagnosis of avascular necrosis of the talus (AVN) and prediction of ankle function for talar fractures are important. The Hawkins sign, as a radiographic predictor, could exclude the possibility of developing ischemic bone necrosis after talar neck fractures, but its relationship with ankle function remains unclear. The purpose of this study was to illustrate the prognostic effect of the Hawkins sign on ankle function after talar neck fractures and to study the value of early MRI in detecting the AVN changes after talus fractures. Cases of talar neck fractures between November 2008 and November 2013 were evaluated. The occurrences of the Hawkins sign and AVN were studied. X-ray imaging was performed at multiple time points from the 4th to the 12th week after the fractures, and MRI examinations were used in the Hawkins sign negative group, with the time span ranging from 1.5 to 12 months. AOFAS scores of the Hawkins sign positive and negative groups were compared during the follow-up. Forty-four cases (48 feet) were evaluated. The occurrence of positive Hawkins sign was 50%, 30%, and 33.3%, the incidence of AVN was 0%, 10%, and 50%, respectively, in type I, type II, and type III and IV talus fractures, respectively. The AOFAS scores showed no statistically significant difference between Hawkins sign positive group and negative group in type I and II fractures. The Hawkins sign positive group had better AOFAS scores than the negative group in type III and IV fractures. However, there was no statistically significant difference between Hawkins sign positive and negative groups when AVN cases were excluded in type III and IV fractures. The Hawkins sign was a reliable predictor excluding the possibility of AVN. It did not have predictive value on the ankle function in low-energy fractures and may predict better ankle function in high-energy fractures. MRI can diagnose AVN during an earlier period, and we believe Hawkins sign negative patients should undergo MRI examinations 12 weeks after the fractures, especially in high-energy traumatic cases. Level III, comparative case series. © The Author(s) 2014.

Operative treatment and avascular necrosis of the hip development disorder.

PubMed

Gavrankapetanović, Ismet; Hadžimehmedagić, Amel; Papović, Adnan; Baždar, Elvir

2014-07-01

The purpose of this research was (1) to evaluate the consequences of an operative treatment of hip developmental disorder in children, (2) to evaluate the significance of hip vascular supply in children through indirect radiological signs, such as morphological changes on femoral head, and to classify them with standard classification methods, and (3) to analyse the research results and make a recommendation for the following treatment dilemma: when is the optimal time for an operative treatment of a hip development disorder? The research is a retrospective and observational analysis based on the classification of indirect radiological signs of local vascular disorder by the Bucholz-Ogden's scale. Materials used for this research are medical records of treated patients at the Clinic for Orthopaedics and Traumatology of the Sarajevo University Clinical Centre. Using a random selection, two groups of 30 patients with hip development disorder were formed. The first group was comprised of patients aged six to 18 months and the second group of patients aged 18-60 months. The medical records used for this research included all necessary anamnestic details and postoperative state treatments with clinical findings and regular radiological check-up findings that include the presence or absence of the ossification nucleus as well as its position. All patients underwent surgery with the same operative technique. Data analysis points include the state at the beginning of the treatment, the postoperative state, the state at discharge as well as control findings that followed the development of the proximal femoral part up to 72 months on average. The analysis covered data such as age, sex, family anamnestic data, clinical findings and radiological findings regarding the femoral head morphology (appearance, size, shape, position and indirect signs showing lack of vascular supply). In addition, data analysis included the types of any previous conservative or operative treatments, the duration of previous conservative treatments and repeated hospitalization. In group 1, 86.6 % were female patients and 80 % in group 2. Family history was positive in 15.6 % in group 1 and 13.3 % in group 2. A total of 51.6 % of all patients started walking on time, while the rest had problems with verticalization. Of all patients, 47 % did not undergo any kind of prior treatment. Only 62.2 % of group 1 patients had ossification nucleus present, while the entire group 2 had it present. Results showed that 24.32 % of group 1 patients had none or minimal signs of avascular necrosis (AVN) while 39.47 % of group 2 had none or minimal signs of AVN; 60.52 % of group 2 patients had signs of AVN. The results of this study show that the performance of a surgical treatment during the age between 12 and 20 months is burdened by the highest percentage of avascular necrosis. Even though AVN can be noticed in other age groups, according to the results of our research, it seems that vascular supply of the hip is the most vulnerable in the period between 12 and 20 months.

Accelerated bone mass senescence after hematopoietic stem cell transplantation.

PubMed

Serio, B; Pezzullo, L; Fontana, R; Annunziata, S; Rosamilio, R; Sessa, M; Giudice, V; Ferrara, I; Rocco, M; De Rosa, G; Ricci, P; Tauchmanovà, L; Montuori, N; Selleri, C

2013-01-01

Osteoporosis and avascular necrosis (AVN) are long-lasting and debilitating complications of hematopoietic stem cell transplantation (HSCT). We describe the magnitude of bone loss, AVN and impairment in osteogenic cell compartment following autologous (auto) and allogeneic (allo) HSCT, through the retrospective bone damage revaluation of 100 (50 auto- and 50 allo-HSCT) long-term survivors up to 15 years after transplant. Current treatment options for the management of these complications are also outlined. We found that auto- and allo-HSCT recipients show accelerated bone mineral loss and micro-architectural deterioration during the first years after transplant. Bone mass density (BMD) at the lumbar spine, but not at the femur neck, may improve in some patients after HSCT, suggesting more prolonged bone damage in cortical bone. Phalangeal BMD values remained low for even more years, suggesting persistent bone micro-architectural alterations after transplant. The incidence of AVN was higher in allo-HSCT recipients compared to auto-HSCT recipients. Steroid treatment length, but not its cumulative dose was associated with a higher incidence of bone loss. Allo-HSCT recipients affected by chronic graft versus host disease seem to be at greater risk of continuous bone loss and AVN development. Reduced BMD and higher incidence of AVN was partly related to a reduced regenerating capacity of the normal marrow osteogenic cell compartment. Our results suggest that all patients after auto-HSCT and allo-HSCT should be evaluated for their bone status and treated with anti-resorptive therapy as soon as abnormalities are detected.

Metabolic bone diseases in patients after allogeneic hematopoietic stem cell transplantation: report from the Consensus Conference on Clinical Practice in chronic graft-versus-host disease.

PubMed

Hautmann, Anke Heidewig; Elad, Sharon; Lawitschka, Anita; Greinix, Hildegard; Bertz, Hartmut; Halter, Joerg; Faraci, Maura; Hofbauer, Lorenz Christian; Lee, Stephanie; Wolff, Daniel; Holler, Ernst

2011-09-01

With improved outcome of allogeneic stem cell transplantation (allo-SCT) for hematologic malignancies, long-term complications gain greater importance. Skeletal complications such as osteoporosis or avascular necrosis (AVN) occur frequently in allogeneic recipients with a cumulative incidence of diminished bone mineral density of 24-50% between 2 and 12 months after allo-SCT and a cumulative incidence of AVN in as many as 19% of patients 3 years after allo-SCT. Here, we present a review as part of the German, Austrian, and Swiss Consensus Conference on clinical practice in chronic graft-versus-host disease, held 2009 in Regensburg. The Consensus Conference aimed to achieve a consensus on the current evidence of diagnosis, prevention, and therapeutic options of late complications after allo-SCT summarizing and discussing the literature on these topics. In this report, we provide recommendations for metabolic bone diseases agreed upon by the working party. This includes guidelines for diagnosis, prevention, and therapeutic options in patients with low bone mass or AVN. © 2011 The Authors. Transplant International © 2011 European Society for Organ Transplantation.

An update on the recent literature on sickle cell bone disease.

PubMed

Osunkwo, Ifeyinwa

2013-12-01

To summarize the findings of the recent publications on sickle cell bone disease (SBD). Individuals with sickle cell disease (SCD) are living longer and develop progressive organ damage including SBD with age. Recent studies suggest alternative radiological diagnostics such as ultrasound and scintigraphy can detect and differentiate between different forms of SBD. MRI with or without diffusion-weighted sequences remains the gold standard. Case reports of cranio-orofacial SBD highlight the rarity of this presentation. Vitamin D deficiency is highly prevalent at all ages, but may not be an independent risk factor for avascular necrosis (AVN). Gene polymorphisms of the Annexin A gene may predict AVN in SCD. A recent study demonstrated reduced days with pain and improved physical activity quality of life following high-dose vitamin D therapy. The high rates of osteopenia and osteoporosis in SCD support the need for research addressing this rising public health problem. Lastly, results of total hip arthroplasty for AVN in SCD has improved significantly over time with the use of cementless prosthetic material and improved supportive care. SBD remains poorly studied. Prospective randomized studies targeting predictors, diagnostics, prevention, and treatment options for SBD are sorely needed.

Interferon β protects against avascular osteonecrosis through interleukin 6 inhibition and silent information regulator transcript-1 upregulation

PubMed Central

Kim, Kyoung Min; Wagle, Sajeev; Moon, Young Jae; Wang, Sung Il; Park, Byung-Hyun; Jang, Kyu Yun; Kim, Jung Ryul

2018-01-01

Synovitis of the affected joint is a common in avascular osteonecrosis (AVN). Increased levels of pro-inflammatory cytokine interleukin-6 (IL-6) have been reported in AVN, but the mechanism of this increase remains unclear. Silent information regulator transcript-1 (SIRT1), an NAD-dependent deacetylase, inhibits the release of inflammatory cytokines. Interferon β (IFN-β) has clear anti-inflammatory properties. We sought to investigate the effects of IFN-β treatment on AVN and to evaluate the specific signal pathway relating to IL-6 and SIRT1 affected during AVN. Using a dissection microscope, AVN was surgically induced in the distal femurs of mice. Exogenous IFN-β was administered to the model mice. The effects of exogenous IFN-β on AVN model mice were assessed using hematoxylin eosin and safranin-O staining, and bone resorption activity was measured using tartrate-resistant acid phosphatase (TRAP) and CD68 staining. Western blots, real-time RT-PCR, and immunohistochemical staining were performed to evaluate the production of SIRT1 and IL-6 in tissues. The RAW 264.7 cell line and bone marrow derived osteoclasts treated with exogenous IFN-β. Histological findings indicated well preserved trabecular bone and decreased osteoclast bone resorption activity in IFN-β treated mice compared with mice in the AVN group. Treatment with IFN-β increased SIRT1 expression and inhibited secretion of IL-6 in this AVN mouse model. IFN-β decreased IL-6 secretion by activating SIRT1 in the RAW 264.7 cell and bone marrow derived osteoclasts. Our work suggests that IFN-β could be used to treat AVN and that both SIRT1 and IL-6 are useful targets for treating patients with AVN. PMID:29423066

Interferon β protects against avascular osteonecrosis through interleukin 6 inhibition and silent information regulator transcript-1 upregulation.

PubMed

Kim, Kyoung Min; Wagle, Sajeev; Moon, Young Jae; Wang, Sung Il; Park, Byung-Hyun; Jang, Kyu Yun; Kim, Jung Ryul

2018-01-09

Synovitis of the affected joint is a common in avascular osteonecrosis (AVN). Increased levels of pro-inflammatory cytokine interleukin-6 (IL-6) have been reported in AVN, but the mechanism of this increase remains unclear. Silent information regulator transcript-1 (SIRT1), an NAD-dependent deacetylase, inhibits the release of inflammatory cytokines. Interferon β (IFN-β) has clear anti-inflammatory properties. We sought to investigate the effects of IFN-β treatment on AVN and to evaluate the specific signal pathway relating to IL-6 and SIRT1 affected during AVN. Using a dissection microscope, AVN was surgically induced in the distal femurs of mice. Exogenous IFN-β was administered to the model mice. The effects of exogenous IFN-β on AVN model mice were assessed using hematoxylin eosin and safranin-O staining, and bone resorption activity was measured using tartrate-resistant acid phosphatase (TRAP) and CD68 staining. Western blots, real-time RT-PCR, and immunohistochemical staining were performed to evaluate the production of SIRT1 and IL-6 in tissues. The RAW 264.7 cell line and bone marrow derived osteoclasts treated with exogenous IFN-β. Histological findings indicated well preserved trabecular bone and decreased osteoclast bone resorption activity in IFN-β treated mice compared with mice in the AVN group. Treatment with IFN-β increased SIRT1 expression and inhibited secretion of IL-6 in this AVN mouse model. IFN-β decreased IL-6 secretion by activating SIRT1 in the RAW 264.7 cell and bone marrow derived osteoclasts. Our work suggests that IFN-β could be used to treat AVN and that both SIRT1 and IL-6 are useful targets for treating patients with AVN.

Does Perfusion MRI After Closed Reduction of Developmental Dysplasia of the Hip Reduce the Incidence of Avascular Necrosis?

PubMed

Gornitzky, Alex L; Georgiadis, Andrew G; Seeley, Mark A; Horn, B David; Sankar, Wudbhav N

2016-05-01

Gadolinium-enhanced perfusion MRI (pMRI) after closed reduction/spica casting for developmental dysplasia of the hip (DDH) has been suggested as a potential means to identify and avoid avascular necrosis (AVN). To date, however, no study has evaluated the effectiveness of pMRI in clinical practice or compared it with other approaches (such as postreduction CT scan) to show a difference in the proportion of AVN. (1) Can a pMRI-based protocol be used immediately post closed reduction to minimize the risk that AVN would develop? (2) What are the overall hip-related outcomes after closed reduction/spica casting using this protocol? (3) Do any patient-specific factors at the time of closed reduction predict future AVN? This was a retrospective cohort study at a large tertiary care children's hospital. Between 2009 and 2013 we treated 43 patients with closed reduction/spica casting for DDH, of whom 33 (77%) received a postreduction pMRI. All patients were indicated for pMRI per treating surgeon preference. A convenience sample totaling 25 hips in 22 patients treated with pMRI was then established using the following exclusion criteria: DDH of neuromuscular/syndromic origin, failed initial closed reduction, less than 1 year of clinical and radiographic followup, and subsequent open reduction. Next, the 40 patients treated with closed reduction between 2004 and 2009 were screened until the chronologically most recent 25 hips (after applying the previously mentioned exclusion criteria) were identified in 21 of the first 34 patients (62%) screened. Although termed the CT group, specific postreduction imaging was not a defined inclusion criterion in this group with the majority (21 of 25 [84%]) receiving postreduction CT and the remainder (four of 25 [16%]) receiving only postreduction radiographs. All hips with globally decreased femoral head perfusion on postreduction pMRI were treated with immediate cast removal followed by repeat closed reduction or open reduction, as per surgeon preference, with two of 33 (6%) requiring such further interventions. Salter criteria were then used to determine the proportion of AVN on radiographs at 1-year and final followup. Secondary outcomes including residual dysplasia and the need for further corrective surgery were ascertained through radiographic and retrospective chart review. At 1-year followup there was no difference in the proportion of AVN in the historical CT group as compared with the pMRI group (six of 25 [24%] versus one of 25 [4%]; odds ratio [OR], 7.6; 95% confidence interval [CI], 0.8-363; p = 0.098). However, by final followup there was a statistically higher proportion of AVN in the CT group (seven of 25 [28%] versus one of 25 [4%]; OR, 9.3; 95% CI, 1.0-438; p = 0.049). No patient with normal perfusion on postreduction pMRI went on to develop AVN. In those pMRI patients in whom a successful reduction was initially obtained, two of 25 (8%) went on to require further corrective surgery and one of 25 (4%) had a redislocation event. With the numbers available, no patient-specific factors at the time of closed reduction were predictive of future AVN, including the patient's age/weight, the presence of an ossific nucleus, history of previous bracing treatment, or the abduction angle in spica cast. A pMRI-based protocol immediately after closed reduction/spica casting may decrease the risk of AVN by helping the surgeon to evaluate femoral head vascularity. Although preliminary in nature, this study could serve to guide further investigation into the potential role of pMRI for the treatment of patients who require closed reduction/spica casting for DDH. Level III, therapeutic study.

Treatment of AVN Using Autologous BM Stem Cells and Activated Platelet-Derived Growth Factor Concentrates.

PubMed

Nandeesh, Nagaraj H; Janardhan, Kiranmayee; Subramanian, Vignesh; Ashtekar, Abhishek Bhushan; Srikruthi, Nandagiri; Koka, Prasad S; Deb, Kaushik

Avascular Necrosis (AVN) of hip is a devastating condition seen in younger individuals. It is the ischemic death of the constituents of the bone cartilage of the hip. The femoral head (FH) is the most common site for AVN. It results from interruption of the normal blood flow to the FH that fits into the hip socket. Earlier studies using autologous bone marrow stem cell concentrate injections have shown encouraging results with average success rates. The current study was designed to improve significantly the cartilage regeneration and clinical outcome. Total of 48 patients underwent autologous bone marrow stem cell and activated platelet-rich plasma derived growth factor concentrate (PRP-GFC) therapy for early and advanced stages AVN of femoral head in a single multi-specialty center. The total treatment was divided into three phases. In the phase I, all the clinical diagnostic measurements such as magnetic resonance imaging (MRI), computed tomography (CT) etc. with respect to the AVN patients and bone marrow aspiration from posterior iliac spine from the patients were carried out. In the phase II, isolation of stem cells and preparation from the patients were performed. Subsequently, in phase III, the stem cells and PRP- GFCs were transplanted in the enrolled patients. Ninety three percent of the enrolled AVN patients showed marked enhancement in the hip bone joint space (more than 3mm) after combined stem cells and PRP-GFC treatment as evidenced by comparison of the pre- and post-treatment MRI data thus indicative of regeneration of cartilage. The treated patients showed significant improvement in their motor function, cartilage regrowth (3 to 10mm), and high satisfaction in the two-year follow-up. Combination of stem cell and PRP-GFC therapy has shown promising cartilage regeneration in 45 out of 48 patients of AVN. This study clearly demonstrates the safety and efficacy of this treatment. Larger numbers of patients need to be evaluated to better understand the efficacy of the combined stem cell and PRP-GFC therapy on AVN patients.

The role of capital realignment versus in situ stabilization for the treatment of slipped capital femoral epiphysis.

PubMed

Souder, Christopher D; Bomar, James D; Wenger, Dennis R

2014-12-01

Slipped capital femoral epiphysis (SCFE) can be treated by a variety of methods with the traditional method of in situ pin fixation being most commonly used. More recently, the Modified Dunn (Mod. Dunn) procedure consisting of capital realignment has been popularized as a treatment method for SCFE, particularly for more severe cases. Over the last 5 years, our institution has selectively used this method for more complex cases. The purpose of this article is to evaluate the differences between these 2 treatment methods in terms of avascular necrosis (AVN) rate, reoperation rate, and complication rate. Eighty-eight hips that were surgically treated for SCFE between July 2004 and June 2012 met our inclusion criteria. The in situ fixation group included 71 hips, whereas 17 hips were anatomically reduced with the Mod. Dunn procedure. Loder classification, severity, acuity, complication rate, and reoperation rate were determined for the 2 cohorts. The χ analysis was performed to evaluate the relationship between the treatment method and outcome. As expected, stable slips did well with in situ pinning with no cases of AVN, even in more severe slips. Ten stable slips were treated with the Mod. Dunn approach and 2 (20%) developed AVN. Unstable slips were more difficult to treat with 3 of the 7 hips stabilized in situ developing AVN (43%). Two of the 7 unstable slips treated by the Mod. Dunn procedure developed AVN (29%). The other outcomes studied (reoperation rate and complication rate) were not significantly related to the surgical treatment method (P = 0.732 and 0.261, respectively). In situ pinning remains a safe and predictable method for treatment of stable SCFE with no AVN noted, even in severe slips. Attempts to anatomically reduce stable slips led to severe AVN in 20% of cases, thus this treatment approach should be considered with caution. Treatment of unstable slips remains problematic with high AVN rates noted whether treated by in situ fixation or capital realignment (Mod. Dunn). Level III retrospective comparative study.

Use of fibular bone graft and cancellous screw fixation in the management of neglected femur neck fractures in young patients.

PubMed

Khani, Ghulam Mustafa Kaim; Hafeez, Kamran; Bux, Muhammad; Rasheed, Nusrat; Ahmed, Naveed; Anjum, M Perwez

2017-01-01

To present the clinical outcome of patients with neglected femur neck fracture treated with fibular bone graft. During May 2010-February 2013, 15 patients younger than 35 years of age with neglected fracture neck of femur were managed with non-vascularized fibular graft and cannulated screws. Fractures were classified according to Sandhu Classification. Hip function was assessed using Harris hip score. Fifteen patients with mean age of 28.67 years were managed. Mean period of delay from injury to presentation was 3.07 months. Mean follow-up was 18.5 months. Union was achieved in 13 cases. 2 patients developed nonunion with progression of avascular necrosis (AVN). Patients with healed fracture did not show radiological signs of AVN till the past follow-up. Functional status was evaluated at 6 months according to Harris hip score and was poor in 2 patients, fair in 2 patients, good in 6 patients, and excellent in 5 patients. Fibular graft along with two cancellous screws proved to be an effective technique in our cases with neglected femur neck fractures.

[Changes of blood vessels in glucocorticoid-induced avascular necrosis of femoral head in rabbits].

PubMed

Zhou, Q; Li, Q; Yang, L; Liu, F

2000-03-01

To evaluate the effects of fatty tamponade in medullary cavity (serious intramedullary fatty infiltration) on the changes of blood vessels in femoral heads during the pathological process of glucocorticoid (GC)-induced avascular necrosis (AVM) of the femoral heads. The animal model of AVN was established with injection of dexamethasone (DEX) at a high dose of 2.5 mg x kg(-1) x d(-1) in rabbits. Histopathological and morphological changes of blood vessels in the femoral heads were investigated during GC-treatment and after the cessation scanning electron microscope, light microscope, and image analysis. At the 2nd week of DEX-treatment, the fatty tamponade in the medullary cavity appeared in the femoral heads. Intramedullary vascular sinusoids were pressed by an excess of lipocytes and became narrow. The impressions of lipocytes on the surface of vascular sinusoids were definitely displayed on the vascular casts and ink-perfused slides of the femoral heads. These changes were pronounced with the prolongation of the treatment and the vascular sinusoids gradually lost their characteristics. Image analysis showed that the vascular area in the femoral heads continuously decreased. At the 8th week, the effects of fatty tamponade were the most marked. Intramedullary vessels became very sparse and the vascular area decreased to 1/4 of the controls. At the 6th week after the GC-treatment cessation, intramedullary fatty infiltration still existed. The blood vessels were fine and sparse, and the structural features of vascular sinusoids disappeared in the load-bearing regions of the femoral heads. At the 4th week, typical osteonecrosis focuses appeared in the femoral heads. The focuses became larger and the degree of osteonecrosis was increasing with the time of experiment. The fatty tamponade in the medullary cavity is one of the important pathological factors causing ischemic damage to the femoral heads, and plays an important role in the early stage of GC-induced AVN.

Case series of 17 modified Weil's osteotomies for Freiberg's and Köhler's II AVN, with AOFAS scoring pre- and post-operatively.

PubMed

Edmondson, M C; Sherry, K R; Afolayan, J; Armitage, A R; Skyrme, A D

2011-03-01

Treatment for metatarsal head avascular necrosis is largely conservative. For severe or refractory cases there are various surgical options. We have performed a 'modified Weil's osteotomy' of the distal metatarsal in order to manage this problem. We present the largest case series, to our knowledge, with 17 such cases. The patients were scored pre- and post-operatively using the AOFAS Forefoot scoring system. We found that this procedure provided a mean score improvement of 36 points, with a complication rate of 5.9%. We would advocate this modified osteotomy as an effective, reliable and safe treatment option. Copyright © 2009 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Avascular Necrosis

MedlinePlus

Avascular necrosis Overview Avascular necrosis is the death of bone tissue due to a lack of blood supply. Also called osteonecrosis, it can lead to ... blood flow to a section of bone. Avascular necrosis is also associated with long-term use of ...

The treatment of an unstable slipped capital femoral epiphysis by either intracapsular cuneiform osteotomy or pinning in situ: a comparative study.

PubMed

Walton, R D M; Martin, E; Wright, D; Garg, N K; Perry, D; Bass, A; Bruce, C

2015-03-01

We undertook a retrospective comparative study of all patients with an unstable slipped capital femoral epiphysis presenting to a single centre between 1998 and 2011. There were 45 patients (46 hips; mean age 12.6 years; 9 to 14); 16 hips underwent intracapsular cuneiform osteotomy and 30 underwent pinning in situ, with varying degrees of serendipitous reduction. No patient in the osteotomy group was lost to follow-up, which was undertaken at a mean of 28 months (11 to 48); four patients in the pinning in situ group were lost to follow-up, which occurred at a mean of 30 months (10 to 50). Avascular necrosis (AVN) occurred in four hips (25%) following osteotomy and in 11 (42%) following pinning in situ. AVN was not seen in five hips for which osteotomy was undertaken > 13 days after presentation. AVN occurred in four of ten (40%) hips undergoing emergency pinning in situ, compared with four of 15 (47%) undergoing non-emergency pinning. The rate of AVN was 67% (four of six) in those undergoing pinning on the second or third day after presentation. Pinning in situ following complete reduction led to AVN in four out of five cases (80%). In comparison, pinning in situ following incomplete reduction led to AVN in 7 of 21 cases (33%). The rate of development of AVN was significantly higher following pinning in situ with complete reduction than following intracapsular osteotomy (p = 0.048). Complete reduction was more frequent in those treated by emergency pinning and was strongly associated with AVN (p = 0.005). Non-emergency intracapsular osteotomy may have a protective effect on the epiphyseal vasculature and should be undertaken with a delay of at least two weeks. The place of emergency pinning in situ in these patients needs to be re-evaluated, possibly in favour of an emergency open procedure or delayed intracapsular osteotomy. Non-emergency pinning in situ should be undertaken after a delay of at least five days, with the greatest risk at two and three days after presentation. Intracapsular osteotomy should be undertaken after a delay of at least 14 days. In our experience, closed epiphyseal reduction is harmful. Cite this article: Bone Joint J 2015;97-B:412-19. ©2015 The British Editorial Society of Bone & Joint Surgery.

Indomethacin induced avascular necrosis of head of femur

PubMed Central

Prathapkumar, K; Smith, I; Attara, G

2000-01-01

Chemically induced avascular necrosis of bone is a well documented entity. Indomethacin is one of the causes of this condition but is often difficult to recognise. Review of the literature shows that only one case of indomethacin induced avascular necrosis has been reported in the English language between 1966 and the present.
The case of a young healthy man, who developed avascular necrosis of head of femur after prolonged administration of indomethacin, is reported here.


Keywords: indomethacin; avascular necrosis PMID:10964124

Intracapsular cuneiform osteotomy compared with in-situ pinning for the management of slipped capital femoral epiphysis.

PubMed

Zang, Junting; Uchiyama, Katsufumi; Moriya, Mitsutoshi; Li, Zhengwei; Fukushima, Kensuke; Yamamoto, Takeaki; Liu, Jianguo; Feng, Wei; Takahira, Naonobu; Takaso, Masashi

2018-06-01

Intracapsular cuneiform osteotomy was initially introduced to restore the morphology of the proximal femur after slipped capital femoral epiphysis (SCFE). However, whether this procedure results in a higher risk of avascular necrosis (AVN) or lower incidence of cam deformity than in-situ pinning is unclear. The aim of this study was to compare the outcomes of intracapsular cuneiform osteotomy and in-situ pinning to treat SCFE in children. Twenty-three children who suffered from SCFE underwent either intracapsular cuneiform osteotomy (eight patients, eight hips) or in-situ pinning (15 patients, 18 hips) between 2006 and 2014. No patient was lost to follow-up at a mean of 4.5 years. In the osteotomy group, the Japanese Orthopedic Association's hip score system score increased from 50.5 (20-89) to 98.9 (95-100) and from 65.9 (48-90) to 99.0 (44-100) in the in-situ pinning group. On the basis of the slip angle, α angle, and epiphyseal-metaphyseal offset, intracapsular cuneiform osteotomy showed a significantly better result in restoring the morphology of the proximal femur than in-situ pinning (P<0.001). The incidences of AVN, chondrolysis, and lower limb discrepancy were similar between the two groups. On the basis of clinical outcomes, both intracapsular cuneiform osteotomy and in-situ pinning had acceptable abilities to treat SCFE. The incidence of AVN was not related to which technique was used. Osteotomy significantly restored the morphology of the proximal femur.

Corticosteroid administration within 2 weeks after renal transplantation affects the incidence of femoral head osteonecrosis.

PubMed

Saito, Masazumi; Ueshima, Keiichiro; Fujioka, Mikihiro; Ishida, Masashi; Goto, Tsuyoshi; Arai, Yuji; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Fukushima, Wakaba; Kubo, Toshikazu

2014-06-01

It has been suggested that avascular osteonecrosis (AVN) of the femoral head occurs early after systemic steroid administration. The purpose of this study was to investigate the risks regarding development of AVN at a very early stage after renal transplantation. The presence or absence of AVN was determined by MRI at 4 weeks, at 6-12 weeks, at 24 weeks, and at 12 months after renal transplantation in 286 patients (183 males) with a mean age of 39 (16-65) years. The relationship between AVN and age, sex, absence or presence of acute rejection (AR), type of transplanted kidney (living or cadaveric), type of immune suppressor, and total dose of orally administered steroids given in the 2-week period after transplantation was investigated. There were no statistically significant correlations between the development of AVN and age, sex, absence or presence of AR, type of transplanted kidney, or type of immune suppressor. A significant dose-response relationship was found between development of AVN and the total dose of steroid administered in the first 2 weeks after surgery. We found a relationship between AVN development and steroid dose in the early postoperative period, and we also showed a dose-response relationship.

Avascular Necrosis in the Contralateral Hip in Patients With Congenital Femoral Deficiency: A Report of 3 Cases.

PubMed

Brown, Timothy S; Wimberly, Robert L; Birch, John G

2017-01-01

Congenital femoral deficiency is an uncommon clinical entity. We report 3 patients who developed avascular necrosis of the hip in the long (normal) leg during longitudinal observation and/or treatment of congenital femoral deficiency. Patients were identified in limb length discrepancy clinic and their charts were retrospectively reviewed for clinical and radiographic data collection. We describe the occurrence of idiopathic avascular necrosis in the normal limb in patients being followed for limb length discrepancy. Although no conclusion could be drawn about the etiology of the avascular necrosis, we describe a previously undocumented relationship between congenital femoral deficiency and avascular necrosis in the contralateral hip. This occurred in our congenital femoral deficiency population at a rate higher than expected compared with published incidences of avascular necrosis of the hip in children. Level IV-case series.

Using computed tomography to assist with diagnosis of avascular necrosis complicating chronic scaphoid nonunion.

PubMed

Smith, Michael L; Bain, Gregory I; Chabrel, Nick; Turner, Perry; Carter, Chris; Field, John

2009-01-01

The primary aim of our study was to investigate use of long axis computed tomography (CT) in predicting avascular necrosis of the proximal pole of the scaphoid and subsequent fracture nonunion after internal fixation. In addition, we describe a new technique of measuring the position of a scaphoid fracture and provide data on its reproducibility. Thirty-one patients operated on by the senior author for delayed union or nonunion of scaphoid fracture were included. Preoperative CT scans were independently assessed for increased radiodensity of the proximal pole, converging trabeculae, degree of deformity, comminution, and fracture position. Intraoperative biopsies of the proximal pole were obtained and histologically assessed for evidence of avascular necrosis. The radiologic variables were statistically compared with the histologic findings. The presence of avascular necrosis was also compared with postoperative union status, identified on longitudinal CT scans. Preoperative CT features that statistically correlated with histologic evidence of avascular necrosis were increased radiodensity of the proximal pole and the absence of any converging trabeculae between the fracture fragments. The radiologic changes of avascular necrosis and the histologic confirmation of avascular necrosis were associated with persistent nonunion. Preoperative longitudinal CT of scaphoid nonunion is of great value in identifying avascular necrosis and predicting subsequent fracture union. If avascular necrosis is suspected based on preoperative CT, management options include vascularized bone grafts and bone morphogenic protein for younger patients and limited wrist arthrodesis for older patients. Diagnostic II.

Fractures of the talus: experience of two level 1 trauma centers.

PubMed

Elgafy, H; Ebraheim, N A; Tile, M; Stephen, D; Kase, J

2000-12-01

Fifty-eight patients with 60 talar fractures were retrospectively reviewed. There were 39 men and 19 women. The age average was 32 (range, 14-74). Eighty six percent of the patients had multiple injuries. The most common mechanism of injury was a motor vehicle accident. Twenty-seven (45%) of the fractures were neck, 22 (36.7%) process, and 11 (18.3%) body. Forty-eight fractures had operative treatment and 12 had non-operative management. The average follow-up period was 30 months (range, 24-65). Thirty-two fractures (53.3%) developed subtalar arthritis. Two patients had subsequent subtalar fusion. Fifteen fractures (25%) developed ankle arthritis. None of these patients required ankle fusion. Fractures of the body of the talus were associated with the highest incidence of degenerative joint disease of both the subtalar and ankle joints. Ten fractures (16.6%) developed avascular necrosis (AVN), only one of which had subsequent slight collapse. Avascular necrosis occurred mostly after Hawkins Type 3 and 2 fractures of the talar neck. Three rating scores were used in this series to assess the outcome: the American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score, Maryland Foot Score, and Hawkins Evaluation Criteria. The outcome was different with every rating system. However, the outcome with AOFAS Ankle-Hindfoot Score and Hawkins Evaluation Criteria were almost equivalent. Assessment with the three rating scores showed that the process fractures had the best results followed by the neck and then the body fractures.

Medial versus anterior open reduction for developmental hip dislocation in age-matched patients.

PubMed

Hoellwarth, Jason S; Kim, Young-Jo; Millis, Michael B; Kasser, James R; Zurakowski, David; Matheney, Travis H

2015-01-01

The difference between medial (MAOR) and anterior (AAOR) approaches for open reduction of developmental hip dysplasia in terms of risk for avascular necrosis (AVN) and need for further corrective surgery (FCS, femoral and/or acetabular osteotomy) is unclear. This study compared age-matched cohorts undergoing either MAOR or AAOR in terms of these 2 primary outcomes. Prognostic impact of presence of ossific nucleus at time of open reduction was also investigated. Institutional review board approval was obtained. Nineteen hips (14 patients) managed by MAOR were matched with 19 hips (18 patients) managed by AAOR based on age at operation (mean 6.0; range, 1.4 to 14.9 mo). Patients with neuromuscular conditions and known connective tissue disorders were excluded. Primary outcomes assessed at minimum 2 years' follow-up included radiographic evidence of AVN (Kalamchi and MacEwen) or requiring FCS. MAOR and AAOR cohorts were similar regarding age at open reduction, sex, laterality, and follow-up duration. One hip in each group had AVN before open reduction thus were excluded from AVN analysis. At minimum 2 years postoperatively (mean 6.2; range, 1.8 to 11.7 y), 4/18 (22%) MAOR and 5/18 (28%) AAOR met the same criteria for AVN (P=1.0). No predictors of AVN could be identified by regression analysis. Presence of an ossific nucleus preoperatively was not a protective factor from AVN (P=0.27). FCS was required in 4/19 (21%) MAOR and 7/19 (37%) AAOR hips (P=0.48). However, 7/12 (54%) hips failing closed reduction required FCS compared with 4/26 (16%) hips without prior failed closed reduction (P=0.024). Cox regression analysis showed that patients who failed closed reduction had an annual risk of requiring FCS approximately 6 times that of patients without a history of failed closed reduction (hazard ratio=6.1; 95% CI, 1.5-24.4; P=0.009), independent of surgical approach (P=0.55) or length of follow-up (P=0.78). In this study of age-matched patients undergoing either MAOR or AAOR, we found no association between surgical approach and risk of AVN or FCS. In addition, we identified no protective benefit of a preoperative ossific nucleus in terms of development of AVN. However, failing closed reduction was associated with a 6-fold increased annual risk of requiring FCS. To the best of our knowledge, this is the first study comparing these 2 surgical techniques in an age-matched manner. It further corroborates previous studies stating that there may be no difference in risk of AVN based on surgical approach or presence of ossific nucleus preoperatively. Level III-retrospective comparative study.

Evaluation of Marrow Perfusion in the Femoral Head by Dynamic Magnetic Resonance Imaging

PubMed Central

Tsukamoto, Hiroshi; Kang, Young S.; Jones, Lynne C.; Cova, Maria; Herold, Christian J.; McVeigh, Elliot; Hungerford, David S.; Zerhouni, Elias A.

2007-01-01

Rationale and Objectives There is a continuing need for a greater sensitivity of magnetic resonance imaging (MRI) in the diagnosis of avascular necrosis (AVN). Previously, it was demonstrated that a dynamic MRI method, with gadolinium-DTPA (Gd-DTPA) enhancement, can detect acute changes not seen on spin-echo images after arterial occlusion in a dog model. Because venous congestion appears to be a more directly relevant hemodynamic abnormality in a majority of clinical AVN cases, the authors extended the dynamic MRI technique to study changes in venous occlusion. Methods Dynamic MRI of the proximal femur was performed in five adult dogs before and after unilateral ligation of common iliac and lateral circumflex veins. Sixteen sequential gradient-recalled pulse sequence (GRASS) images (time resolution = 45 mseconds, echo time = 9 mseconds, flip angle = 65°) were obtained immediately after a bolus intravenous injection of 0.2 mmol/kg of Gd-DTPA. Simultaneous measurements of regional blood flow were made using the radioactive microsphere method. Results After venous ligation, there was a 25% to 45% decrease in the degree of enhancement compared with preligation values on the ligated side. The decrease in cumulative enhancement (integrated over the entire time course) was statistically significant. The occlusion technique was verified by confirming a statistically significant decrease in blood flow determined by the microsphere method. Conclusions Dynamic Gd-DTPA-enhanced fast MRI technique can detect acute changes in bone marrow perfusion due to venous occlusion. This technique may have applications in the early detection of nontraumatic AVN. PMID:1601616

Cirrhosis is a risk factor for total hip arthroplasty for avascular necrosis.

PubMed

Deleuran, Thomas; Overgaard, Søren; Vilstrup, Hendrik; Jepsen, Peter

2016-06-01

Background and purpose - There are limited data on risk factors for avascular necrosis of the hip, but cirrhosis has been proposed as a risk factor. We examined the association between cirrhosis and incidence of total hip arthroplasty for avascular necrosis. Methods - We used nationwide healthcare data to identify all Danish residents diagnosed with cirrhosis in 1994-2011, and matched them 1:5 by age and sex to non-cirrhotic reference individuals from the general population. We excluded people with a previous total hip arthroplasty, a previous hip fracture, or a previous diagnosis of avascular necrosis. We used stratified Cox regression to estimate the hazard ratio (HR) for cirrhosis patients relative to reference individuals, adjusting for potential confounders. We used the cumulative incidence function to compute 5-year risks. Results - We included 25,421 cirrhosis patients and 114,052 reference individuals. Their median age was 57 years, and 65% were men. 45 cirrhosis patients and 44 reference individuals underwent total hip arthroplasty for avascular necrosis. Cirrhosis patients' HR for a total hip arthroplasty for avascular necrosis was 10 (95% CI: 6-17), yet their 5-year risk of avascular necrosis was only 0.2%. For the reference individuals, the 5-year risk was 0.02%. Interpretation - Cirrhosis is a strong risk factor for avascular necrosis of the hip, but it is rare even in cirrhosis patients.

Cirrhosis is a risk factor for total hip arthroplasty for avascular necrosis

PubMed Central

Deleuran, Thomas; Overgaard, Søren; Vilstrup, Hendrik; Jepsen, Peter

2016-01-01

Background and purpose There are limited data on risk factors for avascular necrosis of the hip, but cirrhosis has been proposed as a risk factor. We examined the association between cirrhosis and incidence of total hip arthroplasty for avascular necrosis. Methods We used nationwide healthcare data to identify all Danish residents diagnosed with cirrhosis in 1994–2011, and matched them 1:5 by age and sex to non-cirrhotic reference individuals from the general population. We excluded people with a previous total hip arthroplasty, a previous hip fracture, or a previous diagnosis of avascular necrosis. We used stratified Cox regression to estimate the hazard ratio (HR) for cirrhosis patients relative to reference individuals, adjusting for potential confounders. We used the cumulative incidence function to compute 5-year risks. Results We included 25,421 cirrhosis patients and 114,052 reference individuals. Their median age was 57 years, and 65% were men. 45 cirrhosis patients and 44 reference individuals underwent total hip arthroplasty for avascular necrosis. Cirrhosis patients’ HR for a total hip arthroplasty for avascular necrosis was 10 (95% CI: 6–17), yet their 5-year risk of avascular necrosis was only 0.2%. For the reference individuals, the 5-year risk was 0.02%. Interpretation Cirrhosis is a strong risk factor for avascular necrosis of the hip, but it is rare even in cirrhosis patients. PMID:26900635

Avascular Necrosis of the Capitate

PubMed Central

Bekele, Wosen; Escobedo, Eva; Allen, Robert

2011-01-01

Avascular necrosis of the capitate is a rare entity. The most common reported etiology is trauma. We report a case of avascular necrosis of the capitate in a patient with chronic wrist pain that began after a single episode of remote trauma. PMID:22470799

Biomechanical comparisons between a new avascular necrosis of femaral head stem based on Chinese patients with avascular necrosis and two other designs.

PubMed

Zhang, Qiang; Cheng, Cheng-Kung; Wei, Hung-Wen; Dong, Xiang; Chen, Yi-Ting; Lai, Yu-Shu; Wang, Yan

2013-01-01

There is a relatively high failure rate of the femoral component in patients with avascular necrosis at the intermediate-term follow-up. Improving the geometrical fit of the femoral stem against the medullary canal may help to provide long-term survivorship of the hip replacement for patients with avascular necrosis. We designed a specific stem, based on morphometric studies of proximal femoral canals in Chinese avascular necrosis patients and evaluated the stem by finite element analyses, comparing the novel stem with two commercially available and commonly used stems. The morphometric data from avascular necrosis patients showed specific geometric differences in the proximal femoral canal, including profile curves in both the sagittal and coronary planes than the patients with femoral neck fracture. The shorter stemmed prostheses (Fitmore(®) and our stem) performed better than the longer stemmed prosthesis (VerSys(®)). This is the first study to investigate the femoral geometries of Chinese avascular necrosis patients. Our stem provides better stability and is theoretically beneficial to bone ingrowth, which may increase the long-term stability and fixation of the implant.

Avascular necrosis of the trapezoid bone following carpometacarpal arthroplasty.

PubMed

Kane, Patrick; Waryasz, Greg; Katarincic, Julie

2014-03-03

A 58-year-old female developed avascular necrosis of her trapezoid approximately 3 months after undergoing carpometacarpal arthroplasty. The patient was treated conservatively with immobilization and had complete resolution of her clinical symptoms during her year of follow-up. Additionally, radiographic examination showed complete restoration of the height of her trapezoid approximately 1 year after the index procedure. Avascular necrosis of the trapezoid is extremely rare with very few cases described in the literature. This is the first description of avascular necrosis following carpometacarpal arthroplasty.

Corticosteroid administration within 2 weeks after renal transplantation affects the incidence of femoral head osteonecrosis

PubMed Central

Saito, Masazumi; Ueshima, Keiichiro; Fujioka, Mikihiro; Ishida, Masashi; Goto, Tsuyoshi; Arai, Yuji; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Fukushima, Wakaba; Kubo, Toshikazu

2014-01-01

Background and purpose It has been suggested that avascular osteonecrosis (AVN) of the femoral head occurs early after systemic steroid administration. The purpose of this study was to investigate the risks regarding development of AVN at a very early stage after renal transplantation. Methods The presence or absence of AVN was determined by MRI at 4 weeks, at 6–12 weeks, at 24 weeks, and at 12 months after renal transplantation in 286 patients (183 males) with a mean age of 39 (16–65) years. The relationship between AVN and age, sex, absence or presence of acute rejection (AR), type of transplanted kidney (living or cadaveric), type of immune suppressor, and total dose of orally administered steroids given in the 2-week period after transplantation was investigated. Results There were no statistically significant correlations between the development of AVN and age, sex, absence or presence of AR, type of transplanted kidney, or type of immune suppressor. A significant dose-response relationship was found between development of AVN and the total dose of steroid administered in the first 2 weeks after surgery. Interpretation We found a relationship between AVN development and steroid dose in the early postoperative period, and we also showed a dose-response relationship. PMID:24786907

A case of systemic lupus erythematosus presenting as bilateral avascular necrosis of femur.

PubMed

Adikari, Madura; Gunawardane, Aloka; Illangantilaka, Sachithra; Atukorale, Himantha; Rubasinghe, Jeevanie

2016-08-05

Avascular necrosis occur as a result of diverse etiology. Chronic inflammatory conditions such as systemic lupus erythematosus considered as a recognize cause. Many cases were reported in systemic lupus erythematosus after treating with corticosteroids. We report a case of a corticosteroid naïve patient presented as bilateral avascular necrosis of femoral head and later progressed to a case of systemic lupus erythematosus. A 26 year old lady presented with right sided hip pain and diagnosed as avascular necrosis of the femoral head. After 6 months she presented a similar pain in left hip, which revealed avascular necrosis of left femoral head as well. A probable cause for her clinical presentation could not be found after extensive clinical and laboratory evaluation. Patient reported high erythrocyte sedimentation rate persistently, and over the next few years progressed as a case of systemic lupus erythematosus. Above case illustrated avascular necrosis could be an early musculoskeletal manifestation of systemic lupus erythematosus even in the absence of corticosteroid administration.

Atraumatic Pantalar Avascular Necrosis in a Patient With Alcohol Dependence.

PubMed

Callachand, Fayaz; Milligan, David; Wilson, Alistair

2016-01-01

In the United States, an estimated 10,000 to 20,000 new cases of avascular necrosis are diagnosed each year. We present an unusual case of atraumatic avascular necrosis with widespread hindfoot and midfoot involvement. A 62-year-old female with a history of alcohol dependence and smoking, who had previously been treated for avascular necrosis of the knee, presented with right-sided foot pain and difficulty weightbearing. Imaging studies revealed extensive avascular necrosis of the hindfoot and midfoot, which precluded simple surgical intervention. The patient was followed up for 18 months. In the last 8 months of the 18-month period, the patient managed her symptoms using an ankle-foot orthosis. A diagnosis of avascular necrosis should be considered in patients with atraumatic foot and ankle pain, especially in the presence of risk factors such as alcohol excess and smoking. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Osteosynthesis of ununited femoral neck fracture by internal fixation combined with iliac crest bone chips and muscle pedicle bone grafting

PubMed Central

Baksi, D D; Pal, A K; Baksi, D P

2016-01-01

Background: Ununited femoral neck fracture is seen commonly in developing countries due to delayed presentation or failure of primary internal fixation. Such fractures, commonly present with partial or total absorption of femoral neck, osteonecrosis of femoral head in 8–30% cases with upward migration of trochanter posing problem for osteosynthesis, especially in younger individuals. Several techniques for treatment of such conditions are described like osteotomies or nonvascularied cortical or cancellous bone grafting provided varying degrees of success in terms of fracture union but unsatisfactory long term results occurred due to varying incidence of avascular necrosis (AVN) of femoral head. Moreover, in presence of AVN of femoral head neither free fibular graft nor cancellous bone graft is satisfactory. The vascularied bone grafting by deep circumflex iliac artery based on iliac crest bone grafting, free vascularied fibular grafting and muscle pedicle periosteal grafting showed high incidence of success rate. Osteosynthesis is the preferred treatment of choice in ununited femoral neck fracture in younger individuals. Materials and Methods: Of the 293 patients operated during the period from June 1977 to June 2009, 42 were lost to followup. Seven patients with gluteus medius muscle pedicle bone grafting (MPBG) were excluded. Thus, out of 244 patients, 208 (85.3%) untreated nonunion and 36 (14.7%) following failure of primary internal fixation were available for studies. Time interval between the date of injury and operation in untreated nonunion cases was mean 6.5 months and in failed internal fixation cases was mean 11.2 months. Ages of the patients varied from 16 to 55 years. Seventy patients had partial and 174 had subtotal absorption of the femoral neck. Evidence of avascular necrosis (AVN) femoral head was found histologically in 135 (54.3%) and radiologically in 48 (19.7%) patients. The patients were operated by open reduction of fracture, cannulated hip screw fixation, iliac crest bone chips and quadratus femoris MPBG. Results: The mean followup is 12.5 years (range 3-35). The union of fractures occurred in 202 (82.8%), delayed union in 18 (7.3%), and established nonunion in 24 (9.8%) patients. Full weight bearing was permitted at 16–22 weeks after union of fractures. Mean Harris hip score at the longest followup was 85.5. Among the complications, superficial wound infection occurred in 20 (8.2%), deep infection in seven (2.9%), and coxa vara in 39 (16%) patients. Preoperative radiodensity of femoral head disappeared mostly after the union of fracture whereas fresh radiodensity of femoral head appeared in 20 (8%) patients; nine (45%) of them developed segmental collapse. Conclusion: Ununited femoral neck fractureis characterized by absorption of femoral neck, posterior cortical defect, smoothening and overriding of fracture surfaces with intervening fibrous tissues associated with or without AVN of femoral head. The above method of osteosynthesis rectified the above pathology and provided satisfactory results with union of fractures in 90.1% patients at long term followup. PMID:27512217

Avascular necrosis of the femoral head after osteosynthesis of femoral neck fracture.

PubMed

Min, Byung-Woo; Kim, Sung-Jin

2011-05-18

The reported incidence of avascular necrosis after femoral neck fracture fixation varies widely, and there is no consensus regarding its risk factors. We evaluated the incidence of avascular necrosis of the femoral head with the use of contemporary techniques for femoral neck fracture fixation. We then sought to determine what potential risk factors influenced the development of avascular necrosis.Between 1990 and 2005, one hundred sixty-three intracapsular femoral neck fractures in 163 patients were treated with internal fixation at our level-I trauma center. All patients were monitored until conversion to total hip arthroplasty or for a minimum of 2 years postoperatively. Ten patients (10 hips) died and 7 patients (7 hips) were lost to follow-up. The remaining 146 patients (146 hips) had a mean 5.2 years of follow-up (range, 3 months to 17 years). The incidence of avascular necrosis was 25.3% (37 hips). The average time to diagnosis of avascular necrosis was 18.8 months (range, 3-47 months). Patient sex, age, interval from injury to surgery, and mechanism of injury were statistically not associated with the development of avascular necrosis. The quality of fracture reduction, adequacy of fixation, degree of displacement, and comminution of the posterior cortex were significantly associated. After we controlled for patient and radiographic characteristics, multivariate analyses indicated that the important predictors for avascular necrosis are poor reduction (odds ratio=13.889) and initial displacement of the fracture (odds ratio=4.693). Copyright 2011, SLACK Incorporated.

Osteonecrosis

MedlinePlus

... humerus). Knees. Shoulders. Ankles. It is also called: Avascular necrosis. Aseptic necrosis. Ischemic necrosis. Who gets it? Anyone ... Fast Facts Oral Health and Bone Disease Osteonecrosis (Avascular Necrosis), Questions and Answers about Last Reviewed: 10/30/ ...

[RESEARCH PROGRESS OF EXPERIMENTAL ANIMAL MODELS OF AVASCULAR NECROSIS OF FEMORAL HEAD].

PubMed

Yu, Kaifu; Tan, Hongbo; Xu, Yongqing

2015-12-01

To summarize the current researches and progress on experimental animal models of avascular necrosis of the femoral head. Domestic and internation literature concerning experimental animal models of avascular necrosis of the femoral head was reviewed and analyzed. The methods to prepare the experimental animal models of avascular necrosis of the femoral head can be mainly concluded as traumatic methods (including surgical, physical, and chemical insult), and non-traumatic methods (including steroid, lipopolysaccharide, steroid combined with lipopolysaccharide, steroid combined with horse serum, etc). Each method has both merits and demerits, yet no ideal methods have been developed. There are many methods to prepare the experimental animal models of avascular necrosis of the femoral head, but proper model should be selected based on the aim of research. The establishment of ideal experimental animal models needs further research in future.

Surgical hip dislocation for treatment of cam femoroacetabular impingement.

PubMed

Chaudhary, Milind M; Chaudhary, Ishani M; Vikas, K N; KoKo, Aung; Zaw, Than; Siddhartha, A

2015-01-01

Cam femoroacetabular impingement is caused by a misshapen femoral head with a reduced head neck offset, commonly in the anterolateral quadrant. Friction in flexion, adduction and internal rotation causes limitation of the hip movements and pain progressively leading to labral and chondral damage and osteoarthritis. Surgical hip dislocation described by Ganz permits full exposure of the hip without damaging its blood supply. An osteochondroplasty removes the bump at the femoral head neck junction to recreate the offset for impingement free movement. Sixteen patients underwent surgery with surgical hip dislocation for the treatment of cam femoroacetabular impingement by open osteochondroplasty over last 6 years. Eight patients suffered from sequelae of avascular necrosis (AVN). Three had a painful dysplastic hip. Two had sequelae of Perthes disease. Three had combined cam and pincer impingement caused by retroversion of acetabulum. All patients were operated by the trochanteric flip osteotomy with attachments of gluteus medius and vastus lateralis, dissection was between the piriformis and gluteus minimus preserving the external rotators. Z-shaped capsular incision and dislocation of the hip was done in external rotation. Three cases also had subtrochanteric osteotomy. Two cases of AVN also had an intraarticular femoral head reshaping osteotomy. Goals of treatment were achieved in all patients. No AVN was detected after a 6 month followup. There were no trochanteric nonunions. Hip range of motion improved in all and Harris hip score improved significantly in 15 of 16 cases. Mean alpha angle reduced from 86.13° (range 66°-108°) to 46.35° (range 39°-58°). Cam femoroacetabular Impingement causing pain and limitation of hip movements was treated by open osteochondroplasty after surgical hip dislocation. This reduced pain, improved hip motion and gave good to excellent results in the short term.

Post Traumatic Avascular Necrosis of the Proximal Carpal Row--A Case Report.

PubMed

Manohara, Ruben; Sebastin, Sandeep Jacob; Puhaindran, Mark Edward

2015-10-01

We report a case of avascular necrosis of the scaphoid, lunate and triquetrum in a young 21-year-old patient, after a purely ligamentous peri-lunate dislocation of the wrist. He presented with a Mayfield III peri-lunate dislocation after a road traffic accident and underwent an open reduction and internal fixation. Post-operatively, the scapho-lunate gap widened after removal of the temporary K-wires, and he gradually developed avascular necrosis of the scaphoid, lunate and triquetrum, and osteoarthritis of his wrist. We present this unusual case of simultaneous avascular necrosis of multiple carpal bones and discuss the possible risk factors and subsequent management plans for this complex injury. Our patient has no identifiable contributing factors to developing avascular necrosis. We suspect that the violence of the injury and surgery may have compromised the circulation, and advise caution when treating and counseling these patients pre-operatively.

Avascular necrosis of the femoral head presenting as trochanteric bursitis.

PubMed Central

Mandell, B F

1990-01-01

Five patients are described with avascular necrosis of the femoral head who presented with ipsilateral trochanteric bursitis, in the absence of clearcut hip joint disease. Avascular necrosis was indicated by magnetic resonance imaging. It is suggested that clinical trochanteric bursitis, especially when refractory to local corticosteroid treatment, may be the initial sign of hip disease. In the patient with risk factor(s) for avascular necrosis that diagnosis should be considered and evaluated with appropriate studies, such as magnetic resonance imaging, to prevent weight bearing at an early stage and permit possible surgical decompression in the hope of postponing or obviating the need for total hip replacement. PMID:2241294

Avascular necrosis of the femoral head in children with acute lymphoblastic leukemia: a 4- to 9-year follow-up study.

PubMed

Madadi, Firooz; Shamsian, Bibi Shahin; Alavi, Samin; Madadi, Firoozeh; Eajazi, Alireza; Aslani, Afshin

2011-10-05

Avascular necrosis of the femoral head is usually seen in children aged 1.5 to 10 years, reaching a peak incidence between the ages of 4 and 9. Avascular necrosis of the femoral head is a known complication of corticosteroid therapy in acute lymphoblastic leukemia. There are few reports in the literature regarding the natural history of this condition, and there is no consensus on its management. This study examined the natural history of avascular necrosis of the femoral head in children with leukemia. From 1993 to 2006, a total of 865 children with acute lymphoblastic leukemia were admitted to the hematology-oncology ward of a children's hospital. The diagnosis of acute lymphoblastic leukemia was established by bone marrow aspiration. Based on clinical and radiographic findings, avascular necrosis of the femoral head was found in 7 patients; these patients underwent follow-up for 4 to 9 years. Avascular necrosis of the femoral head was clinically symptomatic in all of the children, and they had advanced radiographic collapse of the femoral head. However, the head of the femur was not at risk in any patient based on clinical and radiographic findings. Patients received supportive treatment such as abduction brace and physiotherapy. After 4 to 9 years of follow-up, clinical and radiographic results were satisfactory. Provided that the head of the femur is not at risk, avascular necrosis of the femoral head in children with acute lymphoblastic leukemia may be successfully managed with nonoperative care. Copyright 2011, SLACK Incorporated.

Femoral Head Avascular Necrosis Is Not Caused by Arthroscopic Posterolateral Femoroplasty.

PubMed

Rupp, Robert E; Rupp, Sasha N

2016-05-01

This study was conducted to identify the risk of avascular necrosis of the femoral head after arthroscopic femoroplasty extending to the posterolateral femoral neck, the source of the primary blood supply to the femoral head. Cam lesions of femoroacetabular impingement are typically anterior along the junction of the femoral head and neck. However, anatomic variations can involve the posterolateral vascular region of the femoral head and neck. Femoroplasty involving this vascular region can lead to injury to the blood supply to the femoral head, with subsequent avascular necrosis. If the posterolateral portion of the cam lesion is preserved, persistent femoroacetabular impingement may occur. A retrospective review identified 112 patients who underwent arthroscopic femoroplasty for femoroacetabular impingement over a 2-year period. Of these patients, 14 had femoroplasty that extended to the posterolateral femoral head. Of this group, 5 had undergone magnetic resonance imaging (MRI) after femoroplasty and the other 9 were contacted to undergo MRI of the hip to evaluate for avascular necrosis. A radiologist and the senior author evaluated all MRI scans specifically for avascular necrosis of the femoral head. All procedures were performed by the senior author. Mean age of the 14 patients (8 women and 6 men) with femoroplasty that extended into the posterolateral vascular region of the femoral head was 44 years (range, 23-69 years). All 14 patients underwent MRI evaluation of the affected hip a mean of 25 months (range, 7-44 months) after femoroplasty. No MRI scans showed evidence of avascular necrosis of the femoral head. Femoroplasty of the posterolateral vascular region of the femoral head is not associated with avascular necrosis. Patients with femoroacetabular impingement and a cam lesion extending to the posterolateral femoral head can undergo femoroplasty of this region without the development of avascular necrosis. [Orthopedics. 2016; 39(3):177-180.]. Copyright 2016, SLACK Incorporated.

Autologous Platelet Concentrates as Treatment for Avascular Necrosis of Femoral Head in a Dog.

PubMed

Parra, Estefanía; Vergara, Andrea; Silva, Raúl F

2017-03-01

Avascular necrosis of the femoral head is a developmental disturbance that generally affects young dogs of small breeds and produces ischemic necrosis of the femoral head resulting in an incongruous and malformed joint. The most common treatment is the excisional arthroplasty of the head and femoral neck. The aim of this study is to describe the treatment of avascular necrosis in a Yorkshire dog using intra-articular injections of autologous platelet concentrate. Evaluations were made at 0, 15, 30, 60, and 120 days of treatment, describing the following parameters: clinical gait analysis, perimetry, goniometry, and radiographic evaluations. The results obtained in this case suggest that the autologous platelet concentrate may be an alternative for the treatment of avascular necrosis of the femoral head in dogs. Copyright © 2017 Elsevier Inc. All rights reserved.

Spontaneous and bilateral avascular necrosis of the navicula: Müller-Weiss disease.

PubMed

Aktaş, Erdem; Ayanoğlu, Tacettin; Hatipoğlu, Yasin; Kanatlı, Ulunay

2016-12-01

Although, trauma, foot deformity (pesplanovalgus), systemic diseases such as diabetes mellitus and lupus, drugs (steroids, antineoplastic) and excessive alcohol consumption have all been accused in the etiology of avascular necrosis of the tarsal bones, spontaneous avascular necrosis of the navicular bone, especially in adults, is a rare entity. In this article, we report a 50-year-old female patient with bilateral, spontaneous avascular necrosis of the navicular bone and related severe talonavicular arthrosis. Clinical and radiological findings were concordant with Müller-Weiss disease, which is a rare disease with complex idiopathic foot condition of the adult tarsal navicular bone characterized by progressive navicular fragmentation and talonavicular joint destruction. The patient was successfully treated with two-staged bilateral talonavicular arthrodesis.

Trigger wrist caused by avascular necrosis of the capitate: a case report.

PubMed

Matsui, Yuichiro; Kawamura, Daisuke; Kida, Hiroaki; Hatanaka, Kanako C; Iwasaki, Norimasa

2018-03-27

Trigger wrist is a rare condition first described by Marti in 1960, and various causes have been reported. The condition mostly occurs with finger flexion and extension, and rarely with flexion and extension of the wrist itself. Avascular necrosis of the capitate is also a rare condition, first described by Jönsson in 1942. While some reports of this condition have been published, little is known about its etiology. Therefore, no established treatment exists. We report a case of trigger wrist caused by avascular necrosis of the capitate. A 16-year-old right-handed male who was a high school handball player was referred to our department from a nearby hospital 5 months after the onset of pain in the dorsal aspect of the right wrist, with an unknown cause. At the previous hospital, imaging findings led to a diagnosis of avascular necrosis of the capitate, and conservative treatment with a wrist brace did not improve the pain. At the initial visit to our department, the patient was noted to have a painful trigger wrist that was brought on by wrist flexion and extension. Preoperative imaging findings led to a diagnosis of trigger wrist caused by capitolunate instability secondary to avascular necrosis of the capitate. We performed a partial excision of the proximal capitate with tendon ball interposition. Two years after surgery, the patient's clinical outcome was favorable, with no recurrence of wrist pain or triggering. Both trigger wrist and avascular necrosis of the capitate are rare disorders. When a patient presents with painful triggering at the wrist, surgeons must bear in mind that avascular necrosis of the capitate may result in this phenomenon. We recommend partial excision of the proximal capitate with tendon ball interposition for the treatment of this lesion.

Genetic traits of avascular necrosis of the femoral head analyzed by array comparative genomic hybridization and real-time polymerase chain reaction.

PubMed

Hwang, Jung-Taek; Baik, Seung-Ho; Choi, Jin-Soo; Lee, Kweon-Haeng; Rhee, Seung-Koo

2011-01-03

In an attempt to observe the genetic traits of avascular necrosis of the femoral head, we analyzed the genomic alterations in blood samples of 18 patients with avascular necrosis of the femoral head (9 idiopathic and 9 alcoholic cases) using the array comparative genomic hybridization method and real-time polymerase chain reaction. Several candidate genes were identified that may induce avascular necrosis of the femoral head, and we investigated their role in the pathomechanism of osteonecrosis of bone. The frequency of each candidate gene over all the categories of avascular necrosis of the femoral head was also calculated by real-time polymerase chain reaction. The highest frequency specific genes in each category were FLJ40296, CYP27C1, and CTDP1. FLJ40296 and CYP27C1 had the highest frequency (55.6%) in the idiopathic category. FLJ40296 had a high frequency (44.4%) in the alcoholic category, but CYP27C1 had a relatively low frequency (33.3%) in the alcoholic category. However, CTDP1 showed a significantly high frequency (55.6%) in the alcoholic category and a low frequency (22.2%) in the idiopathic category. Although we statistically analyzed the frequency of each gene with Fisher's exact test, we could not prove statistical significance due to the small number of samples. Further studies are needed with larger sample numbers. If the causal genes of avascular necrosis of the femoral head are found, they may be used for early detection, prognosis prediction, and genomic treatment of avascular necrosis of the femoral head in the future. Copyright 2011, SLACK Incorporated.

Fresh-Stored Osteochondral Allograft for Treatment of Osteochondritis Dissecans the Femoral Head

DTIC Science & Technology

2010-01-01

rotational osteotomy for treatment of avascular necrosis of the femoral head. Arch Orthop Trauma Surg. 1996;115:80–84. Volume 468, Number 2, February 2010...14. Hall FM. Osteochondrosis dissecans and avascular necrosis of bone. (Comment on: Skeletal Radiol. 1990;19(6):419–421.) Skeletal Radiol. 1991;20...439–456. 28. Schneider W, Aigner N, Pinggera O, Knahr K. Intertrochanteric osteotomy for avascular necrosis of the head of the femur: sur- vival

Avascular necrosis of the femoral head at 2 years after pertrochanteric fracture surgery: Case report.

PubMed

Deleanu, Bogdan; Prejbeanu, Radu; Vermesan, Dinu; Honcea, Lucian; Mioc, Mihail Lazar; Tsiridis, Eleftherios; Predescu, Vlad

2016-02-01

The avascular necrosis of the femoral head represents the death of bone tissue due to the lack of blood supply. The disease has a progressive evolution and left untreated leads to femoral head collapse and severe arthritis. We present a case of a pertrochanteric fracture which has been successfully operated with a dynamic interlocking trochanteric gamma nail on the right hip. At 2 years after surgery the patient developed an incipient avascular necrosis of the femoral head. Despite the good positioning of the implant, we considered that the source of the pain was an intolerance of the implant, and thus we removed it. After implant removal, the patient was kept under observation and conservative treatment, to prevent further damage to the right hip and allow the healing to occur. At 6 months after the gamma nail was removed the X-rays revealed advanced avascular necrosis of the femoral head and secondary osteoarthritis on the right hip. The patient underwent surgery with an uncemented total hip arthroplasty. There are a few discussions regarding the avascular necrosis of the femoral head. These discussions may include the predisposing risk factors, the treatment of choice and the postoperative complications. The avascular necrosis of the femoral head is a complication of pertrochanteric fractures that can not be foreseen or avoided. The optimal treatment in these cases is uncemented total hip arthroplasty.

Slipped Capital Femoral Epiphysis

MedlinePlus

... SCFE? The most serious complications of SCFE are avascular necrosis (a lack of blood flow to the bone) and chondrolysis (decay of cartilage). Avascular necrosis is more common in patients who have unstable ...

Conservative treatment of sickle cell avascular necrosis of the femoral head.

PubMed

Washington, E R; Root, L

1985-01-01

Treatment of avascular necrosis of the femoral head in adolescents with sickle cell anemia has not yet been standardized. In this study we review the literature and report on three patients with the Legg-Perthes-type avascular necrosis associated with sickle cell disease. These patients were successfully treated by partial weight-bearing with crutches and active range-of-motion exercises. We have examined physiologic and anatomic factors in this specific disease syndrome, which suggest that this may be the preferred method of treatment.

Prednisone

MedlinePlus

... improves when the drug is decreased or discontinued. Avascular Necrosis of Bone For reasons that are not known, ... joint damage, most often of the hips. In avascular necrosis (or osteonecrosis, meaning “bone death”) of the hip, ...

Non-vascularized iliac bone grafting for scaphoid nonunion with avascular necrosis.

PubMed

Kim, Jihyeung; Park, Jin Woo; Chung, Jeehyeok; Jeong Bae, Kee; Gong, Hyun Sik; Baek, Goo Hyun

2018-01-01

We present the surgical outcomes of non-vascularized bone grafting taken from the iliac crest in 24 patients with scaphoid nonunion and avascular necrosis. The Fisk-Fernandez technique was used in 11 patients, and cancellous bone grafting was used in 13 patients. Bony union was achieved in 22 of the 24 patients. Non-vascularized iliac bone grafting can be used for the surgical management of scaphoid nonunion with avascular necrosis. Although revascularization of the proximal fragment after surgery was not evaluated, bony union was confirmed in nearly all patients. IV.

Surgical hip dislocation for treatment of cam femoroacetabular impingement

PubMed Central

Chaudhary, Milind M; Chaudhary, Ishani M; Vikas, KN; KoKo, Aung; Zaw, Than; Siddhartha, A

2015-01-01

Background: Cam femoroacetabular impingement is caused by a misshapen femoral head with a reduced head neck offset, commonly in the anterolateral quadrant. Friction in flexion, adduction and internal rotation causes limitation of the hip movements and pain progressively leading to labral and chondral damage and osteoarthritis. Surgical hip dislocation described by Ganz permits full exposure of the hip without damaging its blood supply. An osteochondroplasty removes the bump at the femoral head neck junction to recreate the offset for impingement free movement. Materials and Methods: Sixteen patients underwent surgery with surgical hip dislocation for the treatment of cam femoroacetabular impingement by open osteochondroplasty over last 6 years. Eight patients suffered from sequelae of avascular necrosis (AVN). Three had a painful dysplastic hip. Two had sequelae of Perthes disease. Three had combined cam and pincer impingement caused by retroversion of acetabulum. All patients were operated by the trochanteric flip osteotomy with attachments of gluteus medius and vastus lateralis, dissection was between the piriformis and gluteus minimus preserving the external rotators. Z-shaped capsular incision and dislocation of the hip was done in external rotation. Three cases also had subtrochanteric osteotomy. Two cases of AVN also had an intraarticular femoral head reshaping osteotomy. Results: Goals of treatment were achieved in all patients. No AVN was detected after a 6 month followup. There were no trochanteric nonunions. Hip range of motion improved in all and Harris hip score improved significantly in 15 of 16 cases. Mean alpha angle reduced from 86.13° (range 66°–108°) to 46.35° (range 39°–58°). Conclusion: Cam femoroacetabular Impingement causing pain and limitation of hip movements was treated by open osteochondroplasty after surgical hip dislocation. This reduced pain, improved hip motion and gave good to excellent results in the short term. PMID:26538754

Logistic regression analysis of factors associated with avascular necrosis of the femoral head following femoral neck fractures in middle-aged and elderly patients.

PubMed

Ai, Zi-Sheng; Gao, You-Shui; Sun, Yuan; Liu, Yue; Zhang, Chang-Qing; Jiang, Cheng-Hua

2013-03-01

Risk factors for femoral neck fracture-induced avascular necrosis of the femoral head have not been elucidated clearly in middle-aged and elderly patients. Moreover, the high incidence of screw removal in China and its effect on the fate of the involved femoral head require statistical methods to reflect their intrinsic relationship. Ninety-nine patients older than 45 years with femoral neck fracture were treated by internal fixation between May 1999 and April 2004. Descriptive analysis, interaction analysis between associated factors, single factor logistic regression, multivariate logistic regression, and detailed interaction analysis were employed to explore potential relationships among associated factors. Avascular necrosis of the femoral head was found in 15 cases (15.2 %). Age × the status of implants (removal vs. maintenance) and gender × the timing of reduction were interactive according to two-factor interactive analysis. Age, the displacement of fractures, the quality of reduction, and the status of implants were found to be significant factors in single factor logistic regression analysis. Age, age × the status of implants, and the quality of reduction were found to be significant factors in multivariate logistic regression analysis. In fine interaction analysis after multivariate logistic regression analysis, implant removal was the most important risk factor for avascular necrosis in 56-to-85-year-old patients, with a risk ratio of 26.00 (95 % CI = 3.076-219.747). The middle-aged and elderly have less incidence of avascular necrosis of the femoral head following femoral neck fractures treated by cannulated screws. The removal of cannulated screws can induce a significantly high incidence of avascular necrosis of the femoral head in elderly patients, while a high-quality reduction is helpful to reduce avascular necrosis.

Steroid Induced Bilateral Avascular Necrosis of Head of Femur in an Adult Male Patient - A Case Report.

PubMed

Jadeja, Dharamvirsinh; Solanki, Vipul; Chavada, Bhavesh; Tripathi, Chandrabhanu

2016-01-01

A 28 year old male patient, known case of pemphigus vulgaris was on dexamethasone pulse therapy. Total 7 pulses were given after that he developed avascular necrosis of head of femur on both sides, which was confirmed by digital X- ray and MRI. Avascular necrosis is a disabling and progressive condition in young patients gradually leads to femoral head collapse and eventual total hip arthroplasty. As per WHO-UMC causality assessment criteria, the association between reaction and drug was possible, Naranjo's score was 7. According to Modified Schumock and Thornton's criteria, this reaction was not preventable. The Modified Hartwig and Siegel's scale showed that the reaction was severe (level 6). Here we present a case where the use of steroid for pemphigus vulgaris resulting in the development of bilateral avascular necrosis of head of femur.

Use of the medial femoral condyle vascularized bone flap in traumatic avascular necrosis of the navicular: a case report.

PubMed

Holm, Janson; Vangelisti, Garrett; Remmers, Jared

2012-01-01

The medial femoral condyle vascularized bone flap has a high success rate in published literature regarding its use in nonunions and avascular necrosis of the upper and lower extremities. It is reported to have minimal donor site morbidity and the ability to provide structural support and torsional strength to load-bearing areas. The flap has found particular success in the treatment of scaphoid nonunions. The tarsal navicular, similar to the scaphoid, is largely articular cancellous bone with little surface area for vascular inflow. These anatomic features make the navicular prone to nonunion and avascular necrosis in traumatic scenarios. We describe a case of nonunion and avascular necrosis of the tarsal navicular occurring as sequelae of a high-impact midfoot injury sustained in an automobile accident. After an initial attempt at open reduction and internal fixation with midfoot bridge plating, subsidence and nonunion resulted. An attempt at arthrodesis of the talonavicular and naviculocuneiform joints was then undertaken. This too failed, leading to the development of additional collapse and avascular necrosis. The site was treated with a medial femoral condyle vascularized bone flap. In this single case, the patient returned to pain-free ambulation and reported excellent outcomes and functional capacity. Although we present a successful case, a larger case series is necessary to establish the use of this flap as a reliable option for the treatment of nonunion and avascular necrosis of the tarsal navicular. Copyright © 2012 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Genetics Home Reference: Legg-Calvé-Perthes disease

MedlinePlus

... link) LEGG-CALVE-PERTHES DISEASE MedGen (1 link) Avascular necrosis of the capital femoral epiphysis Sources for This ... at onset-dependent presentations of premature hip osteoarthritis, avascular necrosis of the femoral head, or Legg-Calvé-Perthes ...

Deployment After Limb Salvage for High-Energy Lower-Extremity Trauma

DTIC Science & Technology

2012-01-01

idiopathic avascular necrosis of the talus, and one had an iatrogenic nerve injury after pelvic surgery. Six of the patients underwent circular external... avascular necrosis Unknown 10 40 Distal tibia fracture Fall from height 11 38 Calcaneus fracture, fifth metatarsal fracture, ankle fracture, talus...injury, and one fall from height). One patient developed idiopathic avascular ne- crosis of the talus without a precipitating injury, and one de

Avascular necrosis of the femoral head in patients treated for leukaemia. Assessment of the need for a diagnostic protocol.

PubMed

Alguacil Pinel, J; Vila Vives, P; Salom Taverner, M

To evaluate the incidence of avascular necrosis of the hip in leukaemia patients treated in our hospital with high doses of corticosteroids in order to evaluate the necessity for an early detection protocol. Observational-descriptive and retrospective study from 2005 to 2016 of 253 patients diagnosed with paediatric leukaemia. Patients with musculoskeletal pathology were identified and patients with avascular necrosis were analysed. A total of 26 patients (10%) had musculoskeletal symptoms. Three patients with avascular necrosis (1.2%) were analysed. One girl, 7 years old, was treated conservatively with traction - suspension and discharge. Two boys, an 11 and a 15.4 year-old,who developed graft-versus-host disease secondary to bone marrow transplantation, and whose treatment included high doses of corticosteroids, developed avascular necrosis of the hip. One was treated with bisphosphonates and forage and the other ended up with a total hip arthroplasty. The occurrence of musculoskeletal symptoms during the treatment of leukaemia is different according to the bibliographic series (0.43 -12.6%). Some authors observe an increased risk in female patients between the ages of 10 and 17. A retrospective study reveals that there is a delay of 3.9 months in the diagnosis of CAP since the onset of pain. Other authors relate NAV to loading joints, age and high doses of corticosteroids. Based on the low incidence of avascular necrosis of the hip in our 14-year-old population treated for leukaemia, the creation of diagnostic protocols seems not to be necessary. However, close monitoring of patients with potential risk factors recognized in the literature, is advisable. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Patterns of Opioid Use in Sickle Cell Disease

PubMed Central

Han, Jin; Saraf, Santosh L.; Zhang, Xu; Gowhari, Michel; Molokie, Robert E.; Hassan, Johara; Alhandalous, Chaher; Jain, Shivi; Younge, Jewel; Abbasi, Taimur; Machado, Roberto F.; Gordeuk, Victor R.

2016-01-01

Pain, the hallmark complication of sickle cell disease (SCD), is largely managed with opioid analgesics in the United States, but comprehensive data regarding the long-term use of opioids in this patient population is lacking. The pain medication prescription records from a cohort of 203 SCD patients were analyzed. Twenty-five percent were not prescribed opioid medications while 47% took only short-acting opioids, 1% took only long-acting opioids, and 27% took a combination of short-acting and long-acting opioids. The median (interquartile range) daily opioid dose was 6.1 mg (1.7-26.3 mg) of oral morphine equivalents, which is lower than the published opioid use among patients with other pain syndromes. The dose of opioids correlated with the number of admissions due to vaso-occlusive crisis (VOC) (r=0.53, p<0.001). When the patients were grouped into quartiles based on daily dose opioid use, a logistic regression model showed that history of avascular necrosis (AVN) (OR 2.87, 95% CI: 1.37-6.02, p=0.005), 25-OHD levels (OR 0.59, 95% CI: 0.38-0.93, p=0.024) and total bilirubin concentration (OR 0.64, 95% CI: 0.42-0.99, p=0.043) were independently associated with opioid use quartiles. In conclusion, doses and types of opioid medications used by adult SCD patients vary widely. Our findings implicate AVN and lower vitamin D levels as factors associated with higher opioid use. They also suggest an association of higher bilirubin levels, possibly suggesting higher hemolytic rate, with lower opioid use. PMID:27466799

Macroscopic and microscopic findings in avascular necrosis of the femoral head.

PubMed

Kamal, Diana; Alexandru, D O; Kamal, C K; Streba, C T; Grecu, D; Mogoantă, L

2012-01-01

The avascular necrosis of the femoral head is an illness induced by the cutoff of blood flow to the femoral head and it affects mostly young adults between the ages of 30 and 50 years, raising therapeutic and diagnostic issues. Many risk factors are incriminated in the development of avascular necrosis of the femoral head like: trauma, chronic alcohol consumption, smoking, administration of corticosteroid drugs, most of the cases are considered to be idiopathic. The main goal of our paper is to describe the macroscopic and microscopic variations of the bone structure, which occur in patients with avascular necrosis of the femoral head. The biological material needed for our study was obtained following hip arthroplasty surgery in 26 patients between the ages of 29 and 59 years, which previously were diagnosed with avascular necrosis of the femoral head and admitted in the Orthopedics Department of the Emergency County Hospital of Craiova (Romania) between 2010 and 2011. From a macroscopic point of view, we found well defined areas of necrosis, most of which were neatly demarcated of the adjacent viable tissue by hyperemic areas, loss of shape and contour of the femoral head and transformations of the articular cartilage above the area of necrosis. When examined under the microscope, we found vast areas of fibrosis, narrow bone trabeculae, obstructed blood vessels or blood vessels with clots inside, hypertrophic fat cells, bone sequestration but also small cells and pyknotic nuclei. The microscopic and macroscopic findings on the femoral head sections varied with the patients and the stage of the disease.

Overhead Bryant's Traction Does Not Improve the Success of Closed Reduction or Limit AVN in Developmental Dysplasia of the Hip.

PubMed

Sucato, Daniel J; De La Rocha, Adriana; Lau, Karlee; Ramo, Brandon A

2017-03-01

Preoperative Bryant's overhead traction before closed reduction (CR) in developmental dysplasia of the hip (DDH) remains controversial and its success in increasing CR rates and reducing avascular necrosis (AVN) rates has not been specifically reported in a large cohort. IRB-approved retrospective study of patients (below 3 y)who were treated with attempted CR for idiopathic DDH from 1980 to 2009. Successful CR was defined as a hip that remained reduced and did not require repeat CR or open reduction. Patients were grouped by age, hip instability [Ortolani positive (reducible) vs. fixed dislocation], and Tonnis classification and rates of successful CR were compared between groups with P<0.05. A total of 342 hips were included with a mean age of 0.9 years (0.2 to 2.8 y) and a mean follow-up of 10.4 years (2.0 to 27.7 y). There were 269 hips with fixed dislocations and 73 Ortolani-positive hips. Traction was used in 276 hips. There was no difference in traction utilization in the 3 age groups (below 1, below 1.5, and below 2 y) for either Ortolani-positive hips (P=0.947) or fixed dislocations (P=0.943). There was no difference in achieving a successful CR comparing traction (60.9%) and no-traction groups (60.6%) (P=1.00). For Ortolani-positive hips, traction did not improve the incidence of a successful CR for any age group: below 1 year: P=0.19; below 1.5 years: P=0.23; and below 2 years: P=0.25. Similarly, fixed dislocation patients had no benefit from traction: below 1 year: P=0.76; below 1.5 years: P=0.82; and below 2 years: P=0.85. Tonnis classification did predict success of CR but had no influence on traction success. There was no difference in the rate of AVN between the traction (18%) and no-traction (8%) groups for all patients (P=0.15). In this retrospective series, preoperative Bryant's traction does not improve the rate of a successful CR for patients with DDH and has no protective effect on the development of AVN of the femoral head. These results suggest that Bryant's overhead traction may not be warranted for patients below 3 years of age with DDH. Level III.

Analyses of outcomes of one-stage operation for treatment of late-diagnosed developmental dislocation of the hip: 864 hips followed for 3.2 to 8.9 years.

PubMed

Ning, Bo; Yuan, Yi; Yao, Jie; Zhang, Sichng; Sun, Jun

2014-11-28

The one-stage procedure for treatment of older developmental dislocation of the hip (DDH) is used widely. However, the best age group for this operation is still unknown. The aims of our study were to evaluate middle-term outcomes of one-stage surgical treatment of a large number of patients with late-diagnosed DDH, and to explore the best age group for treatment. We retrospectively reviewed 652 patients with a total of 864 hip joints with DDH, all aged >18 months. All the hip joints were treated with one-stage procedures including open reduction, pelvic osteotomy, and femoral shortening. The patients were divided into three groups according to age at surgery: Group I: 1.5-2.5 years; Group II: 2.5-8 years; and Group III: >8 years. The latest clinical and radiographic outcomes, complications and avascular necrosis (AVN) of the femoral head were evaluated and compared among the three groups. The mean age at surgery was 5.8 years (range: 1.5-13.2 years). The average time of follow-up was 6.2 years (range: 3.2-8.9 years). A total of 79.4% of good or excellent outcomes were obtained for clinical functional evaluation according to the McKay classification. For radiographic outcomes, 732 hips (84.7%) were classified as good or excellent according to the Severin classification. A total of 27.4% of all hips had a poor outcome according to the Kalamchi and MacEwen classification for AVN. The poorest outcomes were observed for clinical, radiographic and AVN results in Group III (p < 0.001). Compared with Group I, the better results for clinical and AVN outcomes were found in Group II (p < 0.001). However, similar clinical outcomes were observed between Groups I and II (p > 0.05). A significantly higher incidence of redislocation and residual acetabular dysplasia was observed in Tonnis grade II and III hip dislocation (p < 0.001). One-stage treatment of late-diagnosed DDH had a good outcome in young and middle group. Younger patients achieved better results than older patients. However, the best age group was 2.5-8 years. Tonnis grade II and III DDH is a risk factor for redislocation and residual acetabular dysplasia after the one-stage operation.

Genetically Modified Porcine Skin Grafts for Treatment of Severe Burn Injuries

DTIC Science & Technology

2011-07-01

limited the usefulness of living porcine grafts, since the lack of blood supply soon lead to desiccation and avascular necrosis . Failure of...porcine grafts, since the lack of blood supply soon lead to desiccation and avascular necrosis . Failure of vascularization of xenografts is largely

Morphometric findings in avascular necrosis of the femoral head.

PubMed

Kamal, Diana; Trăistaru, Rodica; Alexandru, D O; Kamal, C K; Pirici, D; Pop, O T; Mălăescu, D Gh

2012-01-01

Avascular necrosis of the femoral head is an illness with a controversial etiology, the trigger event being the suppression of blood flow to the femoral head. The disease affects mostly young adults within their third and fifth decade, the majority of the patients being men. The main risk factors are trauma, chronic alcohol consumption, smoking, corticotherapy. The main goal of our study is to describe the morphometric changes found in the bone tissue of patients diagnosed with avascular necrosis of the femoral head, with different risk factors, by comparing the area of bone trabeculae inside the area of necrosis with that from the adjacent viable tissue. The morphometric study used biological material from 16 patients with ages between 29 and 57 years, who underwent surgery for avascular necrosis of the femoral head. They were admitted in the Orthopedics Department at the Emergency County Hospital in Craiova between 2010 and 2011 and were split into four groups. Group I presented trauma as the main risk factor, Group II had corticotherapy as the defining risk factor, Group III presented chronic alcohol consumption and Group IV was represented by the patients who smoked and exhibited chronic alcohol consumption. There was not a significant statistical difference between the areas of bone trabeculae of the four groups when we compared viable bone tissue to the necrotized one. Knowing the risk factors of the avascular necrosis of the femoral head is critical to the management of the disease, because diagnosing it in an early stage is a necessity for obtaining a good result for conservative treatment.

Pravastatin Protects Against Avascular Necrosis of Femoral Head via Autophagy.

PubMed

Liao, Yun; Zhang, Ping; Yuan, Bo; Li, Ling; Bao, Shisan

2018-01-01

Autophagy serves as a stress response and may contribute to the pathogenesis of avascular necrosis of the femoral head induced by steroids. Statins promote angiogenesis and ameliorate endothelial functions through apoptosis inhibition and necrosis of endothelial progenitor cells, however the process used by statins to modulate autophagy in avascular necrosis of the femoral head remains unclear. This manuscript determines whether pravastatin protects against dexamethasone-induced avascular necrosis of the femoral head by activating endothelial progenitor cell autophagy. Pravastatin was observed to enhance the autophagy activity in endothelial progenitor cells, specifically by upregulating LC3-II/Beclin-1 (autophagy related proteins), and autophagosome formation in vivo and in vitro . An autophagy inhibitor, 3-MA, reduced pravastatin protection in endothelial progenitor cells exposed to dexamethasone by attenuating pravastatin-induced autophagy. Adenosine monophosphate-activated protein kinase (AMPK) is a key autophagy regulator by sensing cellular energy changes, and indirectly suppressing activation of the mammalian target of rapamycin (mTOR). We found that phosphorylation of AMPK was upregulated however phosphorylation of mTOR was downregulated in pravastatin-treated endothelial progenitor cells, which was attenuated by AMPK inhibitor compound C. Furthermore, liver kinase B1 (a phosphorylase of AMPK) knockdown eliminated pravastatin regulated autophagy protein LC3-II in endothelial progenitor cells in vitro . We therefore demonstrated pravastatin rescued endothelial progenitor cells from dexamethasone-induced autophagy dysfunction through the AMPK-mTOR signaling pathway in a liver kinase B1-dependent manner. Our results provide useful information for the development of novel therapeutics for management of glucocorticoids-induced avascular necrosis of the femoral head.

Hip resurfacing arthroplasty in treatment of avascular necrosis of the femoral head.

PubMed

Pyda, Michał; Koczy, Bogdan; Widuchowski, Wojciech; Widuchowska, Małgorzata; Stołtny, Tomasz; Mielnik, Michał; Hermanson, Jacek

2015-01-25

Hip resurfacing is a conservative type of total hip arthroplasty but its use is controversial, especially in patients with osteonecrosis. The aim of this study was analysis of the clinical and radiographic outcomes of hip resurfacing in patients with osteonecrosis. Between 2007 and 2008, 30 hip resurfacing arthroplasties were performed due to osteoarthritis secondary to avascular necrosis of femoral head staged as Ficat III and IV. Patients were qualified to resurfacing arthroplasty when the extent of avascular necrosis using Kerboul's method was <200° and the angle between avascular necrosis and head-neck junction was >20°. All patients were evaluated clinically and radiologically before and 60 months after the operation. The mean Harris Hip Score (HHS) score increased from 47.8 to 94.25 (p<0.05). Physical activity level (University of California, Los Angeles activity score--UCLA activity score) improved from 3.7 to 7.55 (p<0.05). No implant migration was observed. Management of osteonecrosis of the hip with resurfacing arthroplasty seems to be effective in strictly-selected patients.

Hip Resurfacing Arthroplasty in Treatment of Avascular Necrosis of the Femoral Head

PubMed Central

Pyda, Michał; Koczy, Bogdan; Widuchowski, Wojciech; Widuchowska, Małgorzata; Stołtny, Tomasz; Mielnik, Michał; Hermanson, Jacek

2015-01-01

Background Hip resurfacing is a conservative type of total hip arthroplasty but its use is controversial, especially in patients with osteonecrosis. The aim of this study was analysis of the clinical and radiographic outcomes of hip resurfacing in patients with osteonecrosis. Material/Methods Between 2007 and 2008, 30 hip resurfacing arthroplasties were performed due to osteoarthritis secondary to avascular necrosis of femoral head staged as Ficat III and IV. Patients were qualified to resurfacing arthroplasty when the extent of avascular necrosis using Kerboul’s method was <200° and the angle between avascular necrosis and head-neck junction was >20°. All patients were evaluated clinically and radiologically before and 60 months after the operation. Results The mean Harris Hip Score (HHS) score increased from 47.8 to 94.25 (p<0.05). Physical activity level (University of California, Los Angeles activity score – UCLA activity score) improved from 3.7 to 7.55 (p<0.05). No implant migration was observed. Conclusions Management of osteonecrosis of the hip with resurfacing arthroplasty seems to be effective in strictly-selected patients. PMID:25618763

MRI-guidance in percutaneous core decompression of osteonecrosis of the femoral head.

PubMed

Kerimaa, Pekka; Väänänen, Matti; Ojala, Risto; Hyvönen, Pekka; Lehenkari, Petri; Tervonen, Osmo; Blanco Sequeiros, Roberto

2016-04-01

The purpose of this study was to evaluate the usefulness of MRI-guidance for core decompression of avascular necrosis of the femoral head. Twelve MRI-guided core decompressions were performed on patients with different stages of avascular necrosis of the femoral head. The patients were asked to evaluate their pain and their ability to function before and after the procedure and imaging findings were reviewed respectively. Technical success in reaching the target was 100 % without complications. Mean duration of the procedure itself was 54 min. All patients with ARCO stage 1 osteonecrosis experienced clinical benefit and pathological MRI findings were seen to diminish. Patients with more advanced disease gained less, if any, benefit and total hip arthroplasty was eventually performed on four patients. MRI-guidance seems technically feasible, accurate and safe for core decompression of avascular necrosis of the femoral head. Patients with early stage osteonecrosis may benefit from the procedure. • MRI is a useful guidance method for minimally invasive musculoskeletal interventions. • Bone drilling seems beneficial at early stages of avascular necrosis. • MRI-guidance is safe and accurate for bone drilling.

The role of electrical stimulation in the management of avascular necrosis of the femoral head in adults: a systematic review.

PubMed

Al-Jabri, Talal; Tan, Jessica Yan Qi; Tong, Gabriel Yihan; Shenoy, Ravikiran; Kayani, Babar; Parratt, Timothy; Khan, Tahir

2017-07-28

Avascular necrosis of the femoral head causes significant morbidity and occurs in up to 20,000 people per year. A variety of nonoperative and operative measures have been trialled however a definitive treatment algorithm is yet to be established. Young adults in many cases have undergone multiple surgical procedures in their lifetime with increasing risks of complications. Less invasive techniques may help reduce the number of operations required and positively influence the natural history of the disease process. Our aim was to navigate the literature and examine the results of electrical stimulation of the femoral head in avascular necrosis. The following defined search strategy was used to perform a systematic review using MEDLINE and Google Scholar databases: ((avascular necrosis) OR (osteonecrosis)) AND (femoral head) AND ((electrical stimulation) OR (capacitive coupling) OR (pulsed electromagnetic fields)). Articles were reviewed and data compiled into tables for analysis. Fourty six articles were identified with a total of 10 articles meeting the inclusion criteria. 8 articles were prospective studies and 2 were retrospective. Early Ficat stages showed the best responses to treatment via pulsed electromagnetic fields with improvements in both clinical and radiographic parameters. Direct current and capacitative coupling have had a more ambiguous outcome. Pulsed electromagnetic fields may have a role in the management of early avascular necrosis. The paucity of clinical studies into this technique indicates a need for further studies.

Strategies for Managing Massive Defects of the Foot in High-Energy Combat Injuries of the Lower Extremity

DTIC Science & Technology

2010-01-01

infection, or avascular necrosis is extremely difficult. Tibiocalcaneal fusion typically leaves a patient with a leg length discrepancy unless large bone...fractures. J Orthop Trauma 2004;18(5):265–70. 37. Dennison MG, Pool RD, Simonis RB, et al. Tibiocalcaneal fusion for avascular necrosis of the talus

Nilotinib induced avascular necrosis of femoral head in an adult chronic myeloid leukemia patient.

PubMed

Thekkudan, Shinto Francis; Nityanand, Soniya

2018-06-01

We report a rare case of avascular necrosis of femoral head (AVNFH) in an adult chronic myeloid leukemia - chronic phase (CML-CP) patient during due course of therapy with second line Tyrosine Kinase Inhibitor (TKI), Nilotinib. A high index of clinical suspicion should be kept in any symptomatic CML patient on TKI's.

Complete spontaneous avascular necrosis of the adult navicula associated with Mee's growth arrest lines of the great and second toenails.

PubMed

Singh, Dishan; Ferrerro, Andrea

2014-03-01

Spontaneous total avascular necrosis of the tarsal navicula has been well documented in children (Kohler's disease) but is uncommon in adults where partial necrosis is usually seen after trauma or in Müller-Weiss disease. A case of spontaneous complete navicular osteonecrosis in a 46 year old female is described; she had accompanying Mee's leuchonychial lines in the toenails of the great and second toes only; the lines resolved after 9 months. She has been treated with an excision of the navicula and interpositional iliac crest bone graft talo-cuneiform fusion with resolution of her pain. It is postulated that the combination of the Mee's lines and avascular necrosis of the navicula indicates an occlusion of the dorsalis pedis in a predisposed individual. Copyright © 2013 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Patterns of opioid use in sickle cell disease.

PubMed

Han, Jin; Saraf, Santosh L; Zhang, Xu; Gowhari, Michel; Molokie, Robert E; Hassan, Joharah; Alhandalous, Chaher; Jain, Shivi; Younge, Jewel; Abbasi, Taimur; Machado, Roberto F; Gordeuk, Victor R

2016-11-01

Pain, the hallmark complication of sickle cell disease (SCD), is largely managed with opioid analgesics in the United States, but comprehensive data regarding the long-term use of opioids in this patient population is lacking. The pain medication prescription records from a cohort of 203 SCD patients were analyzed. Twenty-five percent were not prescribed opioid medications while 47% took only short-acting opioids, 1% took only long-acting opioids, and 27% took a combination of short-acting and long-acting opioids. The median (interquartile range) daily opioid dose was 6.1 mg (1.7-26.3 mg) of oral morphine equivalents, which is lower than the published opioid use among patients with other pain syndromes. The dose of opioids correlated with the number of admissions due to vaso-occlusive crisis (VOC) (r = 0.53, P < 0.001). When the patients were grouped into quartiles based on daily dose opioid use, a logistic regression model showed that history of avascular necrosis (AVN) (OR: 2.87, 95% CI: 1.37-6.02, P = 0.005), 25-OHD levels (OR: 0.59, 95% CI: 0.38-0.93, P = 0.024) and total bilirubin concentration (OR: 0.64, 95% CI: 0.42-0.99, P = 0.043) were independently associated with opioid use quartiles. In conclusion, doses and types of opioid medications used by adult SCD patients vary widely. Our findings implicate AVN and lower vitamin D levels as factors associated with higher opioid use. They also suggest an association of higher bilirubin levels, possibly suggesting higher hemolytic rate, with lower opioid use. Am. J. Hematol. 91:1102-1106, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Descriptive Epidemiology of Patients Undergoing Total Hip Arthroplasty in Korea with Focus on Incidence of Femoroacetabular Impingement: Single Center Study.

PubMed

Lee, Woo Yong; Hwang, Deuk Soo; Noh, Chang Kyun

2017-04-01

We analyzed the causes leading to total hip arthroplasty (THA), aimed to clarify the incidence of femoroacetabular impingement (FAI) among the causes, and compared the incidence in Korea with those in other countries. From January 2000 to December 2014, 1,206 hips of 818 patients who underwent primary THA at our institute were reviewed retrospectively in terms of radiographs and electronic charts. The radiographs and radiographic parameters were reviewed and measured by 2 of the authors, who are orthopedic surgeons. Patients were categorized in terms of the causes leading to THA as primary osteoarthritis (OA), rheumatoid arthritis (RA), posttraumatic arthritis, post infectious arthritis, avascular necrosis (AVN) of the femoral head, fracture of the femoral head or neck, ankylosing spondylitis (AS), developmental dysplasia of the hip (DDH), Legg-Calvé-Perthes disease (LCPD), FAI, and others. There were 32 patients (3.91%) in the primary OA group, 41 (5.01%) in the RA group, 84 (10.27%) in the posttraumatic arthritis group, 39 (4.77%) in the post infectious arthritis group, 365 (44.62%) in the AVN group, 39 (4.77%) in the fracture group, 21 (2.57%) in the AS group, 52 (6.36%) in the DDH group, 71 (8.68%) in the LCPD group, 52 (6.36%) in the FAI group, and 22 (2.69%) in the 'other' group. The causes leading to THA in Korea differ from those in Western countries. FAI could be causes of severe secondary OA that requires THA in Korea, therefore symptomatic FAI should not be neglected. © 2017 The Korean Academy of Medical Sciences.

Bilateral avascular necrosis of the femoral head due to the use of heroin: A case report.

PubMed

Ozkunt, Okan; Sarıyılmaz, Kerim; Sungur, Mustafa; Ilen, Ferhat; Dikici, Fatih

2015-01-01

Femoral head avascular necrosis is caused by disruption of the blood supply of the femoral head, which finally results in hip dysfunction. Non traumatic osteonecrosis may related with corticosteroid use, alcohol abuse, SLE, hemoglobinopathies or exposure to cytotoxic agents. But avascular necrosis of the femoral head (ANFH) due to heroin use is a rare condition. We report a patient with bilateral ANFH due to heroin use treated by simultaneous bilateral hip arthroplasty. 37 year-old male patient presented with bilateral hip pain that had been occurring for four years. The patient had no history of smoking, excessive drinking, using corticosteroid and the other drugs or trauma but used heroin for 10 years. In clinic and radiologic examination indicated advanced degenerative changes on both hip due to femoral head avascular necrosis. The patient was treated with simultaneous bilateral total hip arthroplasty. After 6 months postoperatively the active hip range of motion was painless. Avascular femoral head necrosis caused by the using of heroin is rare. Ultimately, osteonecrosis of the femoral head occurs through one final common pathway, which is decreased blood flow to the femoral head that leads bone ischemia and death. But it is still unknown that heroin's systemic effects. Intravenous drug use more as a serious problem for today. There is a need for comprehensive studies to demonstrate effects of heroin on bone and vascularity metabolism. Heroin use will be important problem for population. That's why is crucial to understand the effect of heroin. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Avascular Necrosis of Acetabulum: The Hidden Culprit of Resistant Deep Wound Infection and Failed Fixation of Fracture Acetabulum - A Case Report.

PubMed

K, Kandhari V; M, Desai M; S, Bava S; N, Wade R

2015-01-01

Chances of avascular necrosis of acetabulum are rare as it enjoys a rich blood supply. But cases of post - traumatic avascular necrosis of acetabulum following fracture of posterior column have been well documented. Importance of identifying and suspecting the avascular necrosis of acetabulum is essential in cases of failed fixation of fracture acetabulum, previously operated using extensile approach to acetabulum; either extended anterior ilio - femoral or tri - radiate approach. Such patients usually present with repeated deep bone infection or with early failure of fixation with aseptic loosening and migration of its components. We present a similar case. 40 years female presented with inadequately managed transverse fracture of left acetabulum done by anterior extended ilio-inguinal approach. The fixation failed. She presented 6 months later with painful hip. Cemented total hip replacement was performed with reconstruction of acetabulum by posterior column plating. Six months postoperatively patient presented with dislodgement of cup, pelvic discontinuity and sinus in the thigh. Two stage revision surgery was planned. First implant, removal; debridement and antibiotic spacer surgery was performed. At second stage of revision total hip replacement, patient had Paprosky grade IIIb defect in acetabulum. Spacer was removed through the posterior approach. Anterior approach was taken for anterior plating. Intra-operatively external iliac pulsations were found to be absent so procedure was abandoned after expert opinion. Postoperatively digital subtraction angiography demonstrated a chronic block in the external iliac artery and corona mortis was the only patent vascular channel providing vascular to the left lower limb. Thus, peripheral limb was stealing blood supply from the acetabulum to maintain perfusion. Patient was ultimately left with pelvic discontinuity, excision arthroplasty and pseudoarthrosis of the left hip. Avascular necrosis of acetabulum is a rare entity & often not recognized. One should be suspicious about diagnosis of avascular necrosis of acetabulum in select cases of failed acetabular fixation, previously operated via extensile anterior ilio - inguinal approach. Angiographic evaluation is essential in revision cases of failed acetabular fixation. Corona mortis (crown or circle of death) can sometimes act as a savior of limb.

MRI Evaluation of Post Core Decompression Changes in Avascular Necrosis of Hip.

PubMed

Nori, Madhavi; Marupaka, Sravan Kumar; Alluri, Swathi; Md, Naseeruddin; Irfan, Kazi Amir; Jampala, Venkateshwarlu; Apsingi, Sunil; Eachempati, Krishna Kiran

2015-12-01

Avascular necrosis of hip typically presents in young patients. Core decompression in precollapse stage provides pain relief and preservation of femoral head. The results of core decompression vary considerably despite early diagnosis. The role of MRI in monitoring patients post surgically has not been clearly defined. To study pre and post core decompression MRI changes in avascular necrosis of hip. This is a contiguous observational cohort of 40 hips treated by core decompression for precollapse avascular necrosis of femoral head, who had a baseline MRI performed before surgery. Core decompression of the femoral head was performed within 4 weeks. Follow up radiograph and MRI scans were done at six months. Harris hip score preoperatively, 1 month and 6 months after the surgery was noted. Success in this study was defined as postoperative increase in Harris hip score (HHS) by 20 points and no additional femoral collapse. End point of clinical adverse outcome as defined by fall in Harris hip score was conversion or intention to convert to total hip replacement (THR). MRI parameters in the follow up scan were compared to the preoperative MRI. Effect of core decompression on bone marrow oedema and femoral head collapse was noted. Results were analysed using SPSS software version. Harris hip score improved from 57 to 80 in all patients initially. Six hips had a fall in Harris hip score to mean value of 34.1 during follow up (9 to 12 months) and underwent total hip replacement. MRI predictors of positive outcome are lesions with grade A extent, Grade A & B location. Bone marrow oedema with lesions less than 50% involvement, medial and central location. Careful selection of patients by MR criteria for core decompression provides satisfactory outcome in precollapse stage of avascular necrosis of hip.

[Short-term curative effects of Tantalum rod treatment in early avascular necrosis].

PubMed

Ye, Fu-Sheng; Ni, Zhe-Ji; Chu, Xiao-Bing; He, Bang-Jian; Li, Ju; Tong, Pei-Jian

2013-08-01

To explore the recent clinical curative effect of Tantalum rod in treating the early avascular necrosis. From January 2008 to November 2008, the 25 patients (39 hips) with early avascular necrosis accepted tantalum rod placement and included 9 males (11 hips) and 16 females (28 hips) with an average age of 37 years old ranging from 18 to 74 years old. Four patients (6 hips) caused by Alcoholic, 6 patients (8 hips) by hormone, 2 cases (2 hips) by traumatic, 13 cases (23 hips) by idiopathic. Steinberg preoperative stage involved 7 hips in period I, 24 hips in period II, 8 hips in period III. Curative effect analysis included preoperative and postoperative Harris score, radiographic changes and hip replacement for follow-up to accept the end of the femoral head survival rate. All patients were followed up for 6 to 47 months (averaged 37.4 months). All 12 hips imaging appeard progress,including tantalum rod exit in 1 hip, hip hemiarthroplasty collapse in 3 hips, the area increased to avascular necrosis in 8 hips. Six hips accepted total hip replacement, including imaging progress in 5 hips (41.7%, 5/12), no imaging progress in 1 hip (3.7%,1/27). All hips' Kaplan-Meier survival curves showed 6-month survival rate was (97.4 +/- 2.5)% after tantalum stick insertion, 1-year survival rate was (94.7 +/- 3.6), and 2-year survival rate was (88.6 +/- 5.4)%, 3-year survival rate was (72.5 +/- 11.2). It is effective for treatment of avascular necrosis of femoral head in Steinberg I and II by Tantalum rod, and it can effectively relieve femoral head replacement time.

Idiopathic Avascular Necrosis of First Metatarsal Head in a Pediatric Patient.

PubMed

Kwon, Young-Uk; Choi, Jang-Seok; Kong, Gyu-Min; Ha, Byung-Ho

Idiopathic avascular necrosis of the first metatarsal head rarely occurs in pediatrics. The present case of avascular necrosis of the first metatarsal head occurred in a 13-year-old male who came to the clinic with a 9-month history of pain in the first metatarsophalangeal joint. Conservative treatment had been applied for 9 months, but the pain had not been relieved. Therefore, surgical treatment, including decompression and debridement, was performed in the first metatarsal head of the patient. After 6 months of follow-up monitoring, full range of motion of the first metatarsophalangeal joint was observed, and the pain had disappeared. No any other complications had developed during 18 months of follow-up monitoring. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

S3-Guideline non-traumatic adult femoral head necrosis.

PubMed

Roth, A; Beckmann, J; Bohndorf, K; Fischer, A; Heiß, C; Kenn, W; Jäger, M; Maus, U; Nöth, U; Peters, K M; Rader, C; Reppenhagen, S; Smolenski, U; Tingart, M; Kopp, I; Sirotin, I; Breusch, S J

2016-02-01

The treatment of adult non-traumatic avascular necrosis of the femoral head (AVN; N-ANFH) within an estimated incidence of 5000-7000 cases per annum in Germany remains a challenge. Risk factors include steroids, alcohol abuse, chemotherapy and immunosuppressive medication, but a genetic predisposition has been suggested. Early diagnosis of this often bilateral disease process is essential for successful conservative or joint preserving surgical management. In this review, we present the update German consensus S3 guideline "diagnosis and management for N-ANFH" as a concise summary. This systematic review is based on the published literature from January 1, 1970 to April 31, 2013 (German and English language). Inclusion criteria were systematic reviews, meta-analyses and relevant peer review publications. We identified a total of 3715 related publications, of which 422 were suitable according to the SIGN criteria, but only 159 fulfilled our inclusion criteria. Clinical suspicion of N-ANFH mandates radiographic evaluation. If radiographs are normal MRI scans are recommended, which should be evaluated according to the ARCO-classification. Differential diagnoses include transient osteoporosis, bone bruise, insufficiency fracture and destructive arthropathy. Untreated, subchondral fractures commonly occur within 2 years, during which the risk for contralateral involvement is high-thereafter unlikely. Conservative management with Ilomedin and Alendronat can be tried, but other pharmacological or physical treatments are inappropriate. No specific joint preserving procedure can be recommended, but core decompression should be considered in early stages if necrosis is <30 %. In ARCO stages IIIc or IV total hip arthroplasty (THA) should be contemplated, which offers similar outcome compared to osteoarthritis. Young age is the main risk factor for higher revision rates after THA for N-ANFH.

Avascular Necrosis of the Metacarpal Head: A Review of 4 Cases.

PubMed

Aldekhayel, Salah; Ghanad, Erfan; Mudgal, Chaitanya S

2018-04-03

To report on 4 cases of avascular necrosis of the metacarpal head. We retrospectively reviewed 4 patients who received a diagnosis of avascular necrosis of the metacarpal head and were treated from 2000 to 2016. All patients were males with involvement of the dominant hand. Three patients had a history of trauma and/or fractures in another finger and one had a history of fracture in the same finger. The diagnosis was confirmed on regular x-rays and magnetic resonance imaging. Nonsurgical management was offered to all patients (rest, placement of an orthosis, and nonsteroidal anti-inflammatory drugs) for 3 to 6 months. Two patients responded well to nonsurgical management and improved in their symptoms. One patient refused surgical intervention and continued to have persistent pain. The other patient was treated with curettage and bone graft and had total resolution of pain symptoms with full active range of motion. A high index of suspicion is required to diagnose and treat avascular necrosis of the metacarpal head correctly. Treatment options are numerous and require further studies to investigate their effectiveness in the treatment of this rare disease. Therapeutic V. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Avascular necrosis (AVN) of the proximal fragment in scaphoid nonunion: is intravenous contrast agent necessary in MRI?

PubMed

Schmitt, R; Christopoulos, G; Wagner, M; Krimmer, H; Fodor, S; van Schoonhoven, J; Prommersberger, K J

2011-02-01

The purpose of this prospective study is to assess the diagnostic value of intravenously applied contrast agent for diagnosing osteonecrosis of the proximal fragment in scaphoid nonunion, and to compare the imaging results with intraoperative findings. In 88 patients (7 women, 81 men) suffering from symptomatic scaphoid nonunion, preoperative MRI was performed (coronal PD-w FSE fs, sagittal-oblique T1-w SE nonenhanced and T1-w SE fs contrast-enhanced, sagittal T2*-w GRE). MRI interpretation was based on the intensity of contrast enhancement: 0 = none, 1 = focal, 2 = diffuse. Intraoperatively, the osseous viability was scored by means of bleeding points on the osteotomy site of the proximal scaphoid fragment: 0=absent, 1 = moderate, 2 = good. Intraoperatively, 17 necrotic, 29 compromised, and 42 normal proximal fragments were found. In nonenhanced MRI, bone viability was judged necrotic in 1 patient, compromised in 20 patients, and unaffected in 67 patients. Contrast-enhanced MRI revealed 14 necrotic, 21 compromised, and 53 normal proximal fragments. Judging surgical findings as the standard of reference, statistical analysis for nonenhanced MRI was: sensitivity 6.3%, specificity 100%, positive PV 100%, negative PV 82.6%, and accuracy 82.9%; statistics for contrast-enhanced MRI was: sensitivity 76.5%, specificity 98.6%, positive PV 92.9%, negative PV 94.6%, and accuracy 94.3%. Sensitivity for detecting avascular proximal fragments was significantly better (p<0.001) in contrast-enhanced MRI in comparison to nonenhanced MRI. Viability of the proximal fragment in scaphoid nonunion can be significantly better assessed with the use of contrast-enhanced MRI as compared to nonenhanced MRI. Bone marrow edema is an inferior indicator of osteonecrosis. Application of intravenous gadolinium is recommended for imaging scaphoid nonunion. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

[Effect of vascular endothelial growth factor and tumor necrosis factor receptor for treatment of avascular necrosis of the femoral head in rabbits].

PubMed

Hu, Zhi-ming; Zhou, Ming-qian; Gao, Ji-min

2008-12-01

To evaluate the therapeutic effect of vascular endothelial growth factor (VEGF) and tumor necrosis factor receptor (TNFR) on avascular necrosis of the femoral head in rabbits. Avascular necrosis of the femoral head was induced in 26 New Zealand white rabbits by injections of horse serum and prednisolone. The rabbits were then divided into VEGF/TNFR treatment group, VEGF treatment group, and untreated model group, with another 4 normal rabbits as the normal control group. In the two treatment groups, the therapeutic agents were injected percutaneously into the femoral head. Enzyme-linked immunosorbent assay was performed to determine the concentration of TNF-alpha in rabbit serum followed by pathological examination of the changes in the bone tissues, bone marrow hematopoietic tissue and the blood vessels in the femoral head. Compared with the model group, the rabbits with both VEGF and TNFR treatment showed decreased serum concentration of TNF-alpha with obvious new vessel formation, decreased empty bone lacunae in the femoral head and hematopoietic tissue proliferation in the bone marrow cavity. Percutaneous injection of VEGF and TNFR into the femoral head can significantly enhance bone tissue angiogenesis and ameliorate osteonecrosis in rabbits with experimental femoral head necrosis.

[Avascular necrosis of the femoral head].

PubMed

Porubský, Peter; Trč, Tomáš; Havlas, Vojtěch; Smetana, Pavel

Avascular necrosis of the femoral head in adults is not common, but not too rare diseases. In orthopedic practice, it is one of the diseases that are causing implantation of hip replacement at a relatively early age. In the early detection and initiation of therapy can delay the implantation of prosthesis for several years, which is certainly more convenient for the patient and beneficial. This article is intended to acquaint the reader with the basic diagnostic procedures and therapy.

A systematic review of undisplaced femoral neck fracture treatments for patients over 65 years of age, with a focus on union rates and avascular necrosis.

PubMed

Xu, Dan-Feng; Bi, Fang-Gang; Ma, Chi-Yuan; Wen, Zheng-Fa; Cai, Xun-Zi

2017-02-10

It remains unclear whether conservative treatment should be used to treat the common undisplaced femoral neck fractures that develop in the elderly. Herein, we systematically review the rates of union and avascular necrosis after conservative and surgical treatment of undisplaced femoral neck fractures. We searched the EMBASE, PubMed, OVID, Cochrane Library, Web of Science, and Scopus databases for randomized controlled trials or observational studies that assessed the outcomes of conservative or surgical treatments of undisplaced femoral neck fractures. No language or publication year limitation was imposed. Statistical analyses were performed with the aid of the chi-squared test. We evaluated the quality of each publication and the risk of bias. Twenty-nine studies involving 5071 patients were ultimately included; 1120 patients were treated conservatively and 3951 surgically. The union rates were 68.8% (642/933) and 92.6% (635/686) in the former and latter groups, respectively (p < 0.001). The avascular necrosis rate in the conservatively treated group was 10.3% (39/380), while it was 7.7% (159/2074) in the surgically treated group (p = 0.09). Surgery to treat undisplaced femoral neck fractures was associated with a higher union rate and a tendency toward less avascular necrosis than conservative treatment.

[Acupotomy and acupuncture in the treatment of avascular necrosis of femoral head at the early and middle stages:a clinical randomized controlled trial].

PubMed

Wang, Zhanyou; Zhou, Xuelong; Xie, Lishuang; Liang, Dongyue; Wang, Ying; Zhang, Hong-An; Zheng, Jinghong

2016-10-12

To compare the efficacy difference between acupotomy and acupuncture in the treatment of avascular necrosis of femoral head at the early and middle stages. The randomized controlled prospective study method was adopted. Sixty cases of avascular necrosis of femoral head at Ficat-ArletⅠto Ⅱ stages were randomized into an acupotomy group (32 cases) and an acupuncture group (28 cases) by the third part. In the acupotomy group, the acupotomy was adopted for the loose solution at the treatment sites of hip joint, once every two weeks, totally for 3 times. In the acupuncture group, ashi points around the hip joint were selected and stimulated with warm acupuncture therapy, once every day, for 6 weeks. Harris hip score was observed before and after treatment. The efficacy was evaluated in the two groups. Harris hip score was improved significantly after treatment in the two groups (both P <0.05). The result in acupotomy group was better than that in the acupuncture group ( P <0.05). The effective rate was 90.6% (29/32) in the acupotomy group, better than 75.0% (21/28) in the acupuncture group after treatment ( P <0.05). Harris hip score and the effective rate in the acupotomy group are better than those in the treatment with routine acupuncture for avascular necrosis of femoral head at the early and middle stages.

Total Hip Arthroplasty in Patients With Avascular Necrosis After Hematopoietic Stem Cell Transplantation.

PubMed

Vijapura, Anita; Levine, Harlan B; Donato, Michele; Hartzband, Mark A; Baker, Melissa; Klein, Gregg R

2018-03-01

The immunosuppressive regimens required for hematopoietic stem cell transplantation predispose recipients to complications, including avascular necrosis. Cancer-related comorbidities, immunosuppression, and poor bone quality theoretically increase the risk for perioperative medical complications, infection, and implant-related complications in total joint arthroplasty. This study reviewed 20 primary total hip arthroplasties for avascular necrosis in 14 patients. Outcomes were assessed at routine clinical visits and Harris hip scores were calculated. Follow-up radiographs were evaluated for component malposition, loosening, polyethylene wear, and osteolysis. Average follow-up was 44.5 months for all patients. Postoperative clinical follow-up revealed good to excellent outcomes, with significant improvement in functional outcome scores. There were no periprosthetic infections or revisions for aseptic loosening. There was 1 dislocation on postoperative day 40, which was treated successfully with a closed reduction. Two patients with a prior history of venous thromboembolism developed a pulmonary embolus on postoperative day 13 and 77, respectively. Four patients died several months to years after arthroplasty of complications unrelated to the surgical procedure. Total hip arthroplasty can both be safely performed and greatly improve quality of life in recipients of hematopoietic stem cell transplantation who develop avascular necrosis. However, prolonged venous thromboembolism prophylaxis should be carefully considered in this high-risk patient population. [Orthopedics. 2018; 41(2):e257-e261.]. Copyright 2018, SLACK Incorporated.

[Pedicled vascularized bone grafts from the dorsum of the distal radius for treatment of scaphoid nonunions].

PubMed

Sauerbier, Michael; Bishop, Allen T; Ofer, Nina

2009-11-01

Bony healing and reconstruction of the scaphoid with use of a reverse-flow pedicle vascularized bone graft from the dorsal aspect of the distal radius. Revitalization of the proximal fragment in case of avascular necrosis. Scaphoid nonunion, especially of the proximal pole. Nonunion after failed attempts of autogenous nonvascularized bone grafting. Avascular necrosis of the scaphoid (Preiser's disease). Avascular osteonecrosis of other carpal bones (i.e., Kienböck's disease stage II and IIIa). However, these will not be addressed in this paper. Advance carpal collapse (SNAC [scaphoid nonunion advanced collapse] wrist stage II and III). Avascular necrosis with broken proximal pole of the scaphoid. Malformation, disease or previous injury of the vascular system. Reconstruction of the scaphoid by interposition of a vascularized bone graft from the dorsum of the distal radius, where several vascularized bone grafts can be harvested, and fixation by a scaphoid screw. Management Immobilization for 6 weeks in a forearm cast including the first phalanx of the thumb. 48 scaphoid nonunions were treated with 1,2-ICSRA-based (intercompartmental supraretinacular artery) vascularized bone grafts: 34 scaphoid nonunions went on to union at an average of 15.6 weeks after surgery.

MRI Evaluation of Post Core Decompression Changes in Avascular Necrosis of Hip

PubMed Central

Marupaka, Sravan Kumar; Alluri, Swathi; MD, Naseeruddin; Irfan, Kazi Amir; Jampala, Venkateshwarlu; Apsingi, Sunil; Eachempati, Krishna Kiran

2015-01-01

Introduction Avascular necrosis of hip typically presents in young patients. Core decompression in precollapse stage provides pain relief and preservation of femoral head. The results of core decompression vary considerably despite early diagnosis. The role of MRI in monitoring patients post surgically has not been clearly defined. Aim To study pre and post core decompression MRI changes in avascular necrosis of hip. Materials and Methods This is a contiguous observational cohort of 40 hips treated by core decompression for precollapse avascular necrosis of femoral head, who had a baseline MRI performed before surgery. Core decompression of the femoral head was performed within 4 weeks. Follow up radiograph and MRI scans were done at six months. Harris hip score preoperatively, 1 month and 6 months after the surgery was noted. Success in this study was defined as postoperative increase in Harris hip score (HHS) by 20 points and no additional femoral collapse. End point of clinical adverse outcome as defined by fall in Harris hip score was conversion or intention to convert to total hip replacement (THR). MRI parameters in the follow up scan were compared to the preoperative MRI. Effect of core decompression on bone marrow oedema and femoral head collapse was noted. Results were analysed using SPSS software version. Results Harris hip score improved from 57 to 80 in all patients initially. Six hips had a fall in Harris hip score to mean value of 34.1 during follow up (9 to 12 months) and underwent total hip replacement. MRI predictors of positive outcome are lesions with grade A extent, Grade A & B location. Bone marrow oedema with lesions less than 50% involvement, medial and central location. Conclusion Careful selection of patients by MR criteria for core decompression provides satisfactory outcome in precollapse stage of avascular necrosis of hip. PMID:26816966

A Scapholunate Ligament-Sparing Technique Utilizing the Medial Femoral Condyle Corticocancellous Free Flap to Reconstruct Scaphoid Nonunions With Proximal Pole Avascular Necrosis.

PubMed

Kazmers, Nikolas H; Thibaudeau, Stephanie; Levin, L Scott

2016-09-01

This article demonstrates a technique for the treatment of scaphoid fracture waist and proximal pole nonunions with avascular necrosis using a free vascularized medial femoral condyle flap. We present our surgical technique and representative case examples in which the scapholunate ligament, a key structure required to preserve carpal kinematics, is spared. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Outcomes of osteoporotic trochanteric fractures treated with cement-augmented dynamic hip screw

PubMed Central

Gupta, Rakesh Kumar; Gupta, Vinay; Gupta, Navdeep

2012-01-01

Background: Dynamic hip screw (DHS) has been the standard treatment for stable trochanteric fracture patterns, but complications of lag screw cut out from a superior aspect, due to inadequate bone anchorage, occur frequently in elderly osteoporotic patients. Polymethylmethacrylate (PMMA) has been used as an augmentation tool to facilitate fixation stability in cadaveric femora for biomechanical studies and in pathological fractures. However, there are very few reports on the utilization of PMMA cement to prevent these complications in fresh intertrochanteric fractures. A prospective study was conducted to evaluate the outcome and efficacy of PMMA augmented DHS in elderly osteoporotic patients with intertrochanteric fractures. Materials and Methods: The study included 64 patients (AO type31-A2.1 in eight, A2.2 in 29, A2.3 in 17 patients, and 31-A3.1 in five, A3.2 in three, and A3.3 in two patients) with an average age of 72 years (60 – 94 years) of which 60 were available for final followup. PMMA augmentation of DHS was performed in all cases by injecting PMMA cement into the femoral head with a custommade gun designed by the authors. The clinical outcome was rated as per the Salvati and Wilson scoring system at the time of final followup of one year. Results were graded as excellent (score > 31), good (score 24 – 31), fair (score 16 – 23), and poor (score < 16). Results: Fracture united in all patients and the average time to union was 13.8 weeks (range 12 – 16 weeks). At an average followup of 18 months (range 12 – 24 months), no incidence of varus collapse or superior screw cut out was observed in any of the patients in spite of weightbearing ambulation from the early postoperative period. There was no incidence of avascular necrosis (AVN) or cement penetration into the joint in our series. Most of the patients were able to regain their prefracture mobility status with a mean hip pain score of 8.6. Conclusion: Cement augmentation of DHS appears to be an effective method of preventing osteoporosis related complications of fracture fixation in the trochanteric fractures. The technique used for cement augmentation in the present study is less likely to cause possible complications of cement augmentation like thermal necrosis, cement penetration into the joint, and AVN hip. PMID:23325965

[S3 Guideline. Part 3: Non-Traumatic Avascular Necrosis in Adults - Surgical Treatment of Atraumatic Avascular Femoral Head Necrosis in Adults].

PubMed

Maus, U; Roth, A; Tingart, M; Rader, C; Jäger, M; Nöth, U; Reppenhagen, S; Heiss, C; Beckmann, J

2015-10-01

The present article describes the guidelines for the surgical treatment of atraumatic avascular necrosis (aFKN). These include joint preserving and joint replacement procedures. As part of the targeted literature, 43 publications were included and evaluated to assess the surgical treatment. According to the GRADE and SIGN criteria level of evidence (LoE), grade of recommendation (EC) and expert consensus (EK) were listed for each statement and question. The analysed studies have shown that up to ARCO stage III, joint-preserving surgery can be performed. A particular joint-preserving surgery currently cannot be recommended as preferred method. The selection of the method depends on the extent of necrosis. Core decompression performed in stage ARCO I (reversible early stage) or stage ARCO II (irreversible early stage) with medial or central necrosis with an area of less than 30 % of the femoral head shows better results than conservative therapy. In ARCO stage III with infraction of the femoral head, the core decompression can be used for a short-term pain relief. For ARCO stage IIIC or stage IV core decompression should not be performed. In these cases, the indication for implantation of a total hip replacement should be checked. Additional therapeutic procedures (e.g., osteotomies) and innovative treatment options (advanced core decompression, autologous bone marrow, bone grafting, etc.) can be discussed in the individual case. In elective hip replacement complications and revision rates have been clearly declining for decades. In the case of an underlying aFKN, however, previous joint-preserving surgery (osteotomies and grafts in particular) can complicate the implantation of a THA significantly. However, the implant life seems to be dependent on the aetiology. Higher revision rates for avascular necrosis are particularly expected in sickle cell disease, Gaucher disease, or kidney transplantation patients. Furthermore, the relatively young age of the patient with avascular necrosis should be seen as the main risk factor for higher revision rate. The results after resurfacing (today with known restricted indications) and cemented as well as cementless THA in aFKN are comparable for the appropriate indication to those in coxarthrosis or other diagnoses. Regardless of the underlying disease endoprosthetic treatment in aFKN leads to good results. Both cemented and cementless fixation techniques can be recommended. Georg Thieme Verlag KG Stuttgart · New York.

Vascular endothelial growth factor/bone morphogenetic protein-2 bone marrow combined modification of the mesenchymal stem cells to repair the avascular necrosis of the femoral head

PubMed Central

Ma, Xiao-Wei; Cui, Da-Ping; Zhao, De-Wei

2015-01-01

Vascular endothelial cell growth factor (VEGF) combined with bone morphogenetic protein (BMP) was used to repair avascular necrosis of the femoral head, which can maintain the osteogenic phenotype of seed cells, and effectively secrete VEGF and BMP-2, and effectively promote blood vessel regeneration and contribute to formation and revascularization of tissue engineered bone tissues. To observe the therapeutic effect on the treatment of avascular necrosis of the femoral head by using bone marrow mesenchymal stem cells (BMSCs) modified by VEGF-165 and BMP-2 in vitro. The models were avascular necrosis of femoral head of rabbits on right leg. There groups were single core decompression group, core decompression + BMSCs group, core decompression + VEGF-165/BMP-2 transfect BMSCs group. Necrotic bone was cleared out under arthroscope. Arthroscopic observation demonstrated that necrotic bone was cleared out in each group, and fresh blood flowed out. Histomorphology determination showed that blood vessel number and new bone area in the repair region were significantly greater at various time points following transplantation in the core decompression + VEGF-165/BMP-2 transfect BMSCs group compared with single core decompression group and core decompression + BMSCs group (P < 0.05). These suggested that VEGF-165/BMP-2 gene transfection strengthened osteogenic effects of BMSCs, elevated number and quality of new bones and accelerated the repair of osteonecrosis of the femoral head. PMID:26629044

Developmental dysplasia of the hip: impact of sonographic newborn hip screening on the outcome of early treated decentered hip joints-a single center retrospective comparative cohort study based on Graf's method of hip ultrasonography.

PubMed

Tschauner, Christian; Fürntrath, Frank; Saba, Yasaman; Berghold, Andrea; Radl, Roman

2011-12-01

PURPOSE/BACKGROUND/INTRODUCTION: The aim of this study was to retrospectively evaluate the impact of neonatal sonographic hip screening using Graf's method for the management and outcome of orthopaedic treatment of decentered hip joints with developmental dysplasia of the hip (DDH), using three decades (1978-2007) of clinical information compiled in a medical database. Three representative cohorts of consecutive cases of decentered hip joints were selected according to different search criteria and inclusion and exclusion parameters: (1) cohort 1 (1978-1982; n = 80), without sonographic screening; (2) cohort 2.1 (1994-1996; n = 91), with nationwide established general sonographic screening according to the Graf-method; (3) cohort 2.2 (2003-2005; n = 91), with sonographic screening including referred cases for open reduction from non-screened populations. These three cohorts were compared for the following parameters: age at initial treatment, successful closed reduction, necessary overhead traction, necessary adductor-tenotomy, rate of open reduction, rate of avascular necrosis (AVN) and rate of secondary acetabuloplasty. The age at initial treatment was reduced from 5.5 months in the first cohort to 2 months in the two subsequent two cohorts and the rate of successful closed reduction increased from 88.7 to 98.9 and 95.6%, respectively. There was a statistically significant improvement in six out of seven parameters with sonographic hip screening; only the rate of secondary acetabuloplasty did not improve significantly. Compared to the era before the institution of a sonographic hip screening programme according to the Graf-method in Austria in 1992, ultrasound screening based-treatment of decentered hip joints has become safer, shorter and simpler: "safer" means lower rate of AVN, "shorter" means less treatment time due to earlier onset and "simpler" means that the devices are now less invasive and highly standardized.

The "starfield" pattern of cerebral fat embolism from bone marrow necrosis in sickle cell crisis.

PubMed

Dhakal, Laxmi P; Bourgeois, Kirk; Barrett, Kevin M; Freeman, William D

2015-04-01

Sickle cell disease may manifest with cerebrovascular and systemic complications. Sickle crisis that results in avascular necrosis of long bones with resultant cerebral fat embolism syndrome is rare and has a characteristic "starfield" pattern on MRI. This "starfield" MRI pattern should raise suspicion for sickle cell crisis in patients without a known history of the disease, which can lead to earlier sickle cell red blood cell exchange transfusion and treatment. We present a case of a male who presented emergently with acute seizure, coma with a characteristic MRI pattern, which lead to the diagnosis of avascular bone marrow necrosis and cerebral fat embolism syndrome from sickle cell crisis.

Reducing selection bias in case-control studies from rare disease registries.

PubMed

Cole, J Alexander; Taylor, John S; Hangartner, Thomas N; Weinreb, Neal J; Mistry, Pramod K; Khan, Aneal

2011-09-12

In clinical research of rare diseases, where small patient numbers and disease heterogeneity limit study design options, registries are a valuable resource for demographic and outcome information. However, in contrast to prospective, randomized clinical trials, the observational design of registries is prone to introduce selection bias and negatively impact the validity of data analyses. The objective of the study was to demonstrate the utility of case-control matching and the risk-set method in order to control bias in data from a rare disease registry. Data from the International Collaborative Gaucher Group (ICGG) Gaucher Registry were used as an example. A case-control matching analysis using the risk-set method was conducted to identify two groups of patients with type 1 Gaucher disease in the ICGG Gaucher Registry: patients with avascular osteonecrosis (AVN) and those without AVN. The frequency distributions of gender, decade of birth, treatment status, and splenectomy status were presented for cases and controls before and after matching. Odds ratios (and 95% confidence intervals) were calculated for each variable before and after matching. The application of case-control matching methodology results in cohorts of cases (i.e., patients with AVN) and controls (i.e., patients without AVN) who have comparable distributions for four common parameters used in subject selection: gender, year of birth (age), treatment status, and splenectomy status. Matching resulted in odds ratios of approximately 1.00, indicating no bias. We demonstrated bias in case-control selection in subjects from a prototype rare disease registry and used case-control matching to minimize this bias. Therefore, this approach appears useful to study cohorts of heterogeneous patients in rare disease registries.

Two types of bone necrosis in the Middle Triassic Pistosaurus longaevus bones: the results of integrated studies

NASA Astrophysics Data System (ADS)

Surmik, Dawid; Rothschild, Bruce M.; Dulski, Mateusz; Janiszewska, Katarzyna

2017-07-01

Avascular necrosis, diagnosed on the basis of either a specific pathological modification of the articular surfaces of bone or its radiologic appearance in vertebral centra, has been recognized in many Mesozoic marine reptiles as well as in present-day marine mammals. Its presence in the zoological and paleontologic record is usually associated with decompression syndrome, a disease that affects secondarily aquatic vertebrates that could dive. Bone necrosis can also be caused by infectious processes, but it differs in appearance from decompression syndrome-associated aseptic necrosis. Herein, we report evidence of septic necrosis in the proximal articular surface of the femur of a marine reptile, Pistosaurus longaevus, from the Middle Triassic of Poland and Germany. This is the oldest recognition of septic necrosis associated with septic arthritis in the fossil record so far, and the mineralogical composition of pathologically altered bone is described herein in detail. The occurrence of septic necrosis is contrasted with decompression syndrome-associated avascular necrosis, also described in Pistosaurus longaevus bone from Middle Triassic of Germany.

The “Starfield” Pattern of Cerebral Fat Embolism From Bone Marrow Necrosis in Sickle Cell Crisis

PubMed Central

Dhakal, Laxmi P.; Bourgeois, Kirk; Barrett, Kevin M.

2015-01-01

Sickle cell disease may manifest with cerebrovascular and systemic complications. Sickle crisis that results in avascular necrosis of long bones with resultant cerebral fat embolism syndrome is rare and has a characteristic “starfield” pattern on MRI. This “starfield” MRI pattern should raise suspicion for sickle cell crisis in patients without a known history of the disease, which can lead to earlier sickle cell red blood cell exchange transfusion and treatment. We present a case of a male who presented emergently with acute seizure, coma with a characteristic MRI pattern, which lead to the diagnosis of avascular bone marrow necrosis and cerebral fat embolism syndrome from sickle cell crisis PMID:25829988

Effects of Focused Extracorporeal Shock Waves on Bone Marrow Mesenchymal Stem Cells in Patients with Avascular Necrosis of the Femoral Head.

PubMed

Zhai, Lei; Sun, Nan; Zhang, Bo; Liu, Shui-Tao; Zhao, Zhe; Jin, Hai-Chao; Ma, Xin-Long; Xing, Geng-Yan

2016-03-01

To observe the effect of extracorporeal shock waves (ESWs) on bone marrow mesenchymal stem cells (MSCs) in patients with avascular necrosis of the femoral head, we collected bone marrow donated by patients and then cultivated and passaged MSCs in vitro using density gradient centrifugation combined with adherence screening methods. The P3 generation MSCs were divided into the ESW group and the control group. The cell counting kit for MSCs detected some proliferation differences. Cytochemistry, alkaline phosphatase staining and Alizarin red staining were used to determine alkaline phosphatase content. Simultaneously, real-time polymerase factor α1, osteocalcin and peroxisome proliferator-activated receptor γ. Together, the results of our study first indicate that moderate ESW intensity, which is instrumental in enhancing MSC proliferation, inducing conversion of MSCs into osteoblasts, and inhibiting differentiation of MSCs into adipocytes from MSCs, is one of the effective mechanisms for treating avascular necrosis of the femoral head. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

The role of Iloprost on bone edema and osteonecrosis: Safety and clinical results.

PubMed

Pountos, Ippokratis; Giannoudis, Peter V

2018-03-01

Iloprost is a commercially available prostaglandin I 2 (PGI 2 ) analogue that is shown to have antithrombotic, vasodilatative and antiproliferative effects. A number of clinical studies have shown that Iloprost can be effective in the management of bone marrow oedema and the treatment of avascular necrosis. The aim of this manuscript is to present our current understanding on the effect of Iloprost on the treatment of these conditions. Areas covered: The authors offer a comprehensive review of the existing literature on the experimental and clinical studies analysing the effect of Iloprost on bone, bone marrow oedema and avascular necrosis. Expert opinion: The available data from the clinical studies suggest that Iloprost has limited effect in advanced stages of avascular necrosis. However, literature suggests that Iloprost administration can be a viable option in the management of bone marrow oedema and early stages of osteonecrosis. Despite these promising results its effect on bone homeostasis needs further elucidation. Moreover, further data on its safety, dosage and efficiency through randomized multicenter studies are desirable in order to reach final conclusions.

Pharmacological interventions for the prevention of insufficiency fractures and avascular necrosis associated with pelvic radiotherapy in adults.

PubMed

van den Blink, Qurrat U; Garcez, Kate; Henson, Caroline C; Davidson, Susan E; Higham, Claire E

2018-04-23

Pelvic radiotherapy is a treatment delivered to an estimated 150,000 to 300,000 people annually across high-income countries. Fractures due to normal stresses on weakened bone due to radiotherapy are termed insufficiency fractures. Pelvic radiotherapy-related interruption of the blood supply to the hip is termed avascular necrosis and is another recognised complication. The reported incidences of insufficiency fractures are 2.7% to 89% and risk of developing avascular necrosis is 0.5%. These complications lead to significant morbidity in terms of pain, immobility and consequently risk of infections, pressure sores and mortality. To assess the effects of pharmacological interventions for preventing insufficiency fractures and avascular necrosis in adults over 18 years of age undergoing pelvic radiotherapy. We performed electronic literature searches in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and DARE to 19 April 2017. We also searched trial registries. Further relevant studies were identified through handsearching of citation lists of included studies. Randomised controlled trials (RCTs) or non RCTs with concurrent comparison groups including quasi-RCTs, cluster RCTs, prospective cohort studies and case series of 30 or more participants were screened. We included studies assessing the effect of pharmacological interventions in adults over 18 years of age undergoing radical pelvic radiotherapy as part of anticancer treatment for a primary pelvic malignancy. We excluded studies involving radiotherapy for bone metastases. We assessed use of pharmacological interventions at any stage before or during pelvic radiotherapy. Interventions included calcium or vitamin D (or both) supplementation, bisphosphonates, selective oestrogen receptor modulators, hormone replacement therapy (oestrogen or testosterone), denosumab and calcitonin. Two review authors independently assessed trial quality and extracted data. We contacted study authors to obtain missing data. Data were to be pooled using the random-effects model if study comparisons were similar, otherwise results were to be reported narratively. We included two RCTs (1167 participants). The first RCT compared zoledronic acid with placebo in 96 men undergoing pelvic radiotherapy for non-metastatic prostate cancer.The second RCT had four treatment arms, two of which evaluated zoledronic acid plus adjuvant androgen suppression compared with androgen suppression only in 1071 men undergoing pelvic radiotherapy for non-metastatic prostate cancer.Both studies were at a moderate to high risk of bias and all evidence was judged to be of very low certainty.The studies provided no evidence on the primary outcomes of the review and provided limited data in relation to secondary outcomes, such that meta-analyses were not possible. Both studies focused on interventions to improve bone health in relation to androgen deprivation rather than radiation-related insufficiency fractures and avascular necrosis. Few fractures were described in each study and those described were not specific to insufficiency fractures secondary to radiotherapy. Both studies reported that zoledronic acid in addition to androgen deprivation and pelvic radiotherapy led to improvements in BMD; however, the changes in BMD were measured and reported differently. There was no available evidence regarding adverse effects. The evidence relating to interventions to prevent insufficiency fractures and avascular necrosis associated with pelvic radiotherapy in adults is of very low certainty. This review highlights the need for prospective clinical trials using interventions prior to and during radiotherapy to prevent radiation-related bone morbidity, insufficiency fractures and avascular necrosis. Future trials could involve prospective assessment of bone health including BMD and bone turnover markers prior to pelvic radiotherapy. The interventions for investigation could begin as radiotherapy commences and remain ongoing for 12 to 24 months. Bone turnover markers and BMD could be used as surrogate markers for bone health in addition to radiographic imaging to report on presence of insufficiency fractures and development of avascular necrosis. Clinical assessments and patient reported outcomes would help to identify any associated adverse effects of treatment and quality of life outcomes.

Steroid osteopathy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conway, J.J.; Weiss, S.C.

1984-01-01

Patients receiving steroids or having disease processes which increase natural steroid production often demonstrate ''the classic x-ray changes'' of avascular necrosis of bone. Bone scintigraphy in these patients most frequently demonstrates an increased radionuclide localization. The literature suggests that the increased activity is related to healing of the avascular process. In a recent study of Legg-Calve-Perthes Disease (LCPD), 37 of the children had multiple studies and increased activity within the epiphysis during revascularization was extremely rare. Not only are the scintigraphic findings in steroid osteopathy dissimilar to that in healing LCPD, but the time interval for healing is much tomore » short for that of a vascular necrosis and no patients demonstrated an avascular phase on bone scintigraphy. Of 15 children with renal transplants on steroid therapy, 9 demonstrated x-ray and clinical findings of osteopathy. In 8 of 9 instances, bone scintigraphy showed increased localization of radionuclide in the affected bone. Improvement or a return to normal occurred in those patients in whom steroids were discontinued. The following is a proposed mechanism for steroid osteopathy. Steroids affect the osteoblastic and osteoclastic activity of bone and weaken its internal structure. Ordinary stress produces microtrabecular fractures. Fractures characteristically stimulate reactive hyperemia and increase bone metabolism. The result is increased bone radiopharmaceutical localization. The importance of recognizing this concept is that steroid osteopathy is preventable by reducing the administered steroid dose. As opposed to avascular necrosis, bone changes are reversible.« less

Tibiocalcaneal Arthrodesis With a Porous Tantalum Spacer and Locked Intramedullary Nail for Post-Traumatic Global Avascular Necrosis of the Talus.

PubMed

Cohen, Michael M; Kazak, Marat

2015-01-01

Global avascular necrosis of the talus is a devastating complication that usually occurs as a result of a post-traumatic or metabolic etiology. When conservative options fail, tibiocalcaneal arthrodesis is generally indicated in conjunction with massive bone grafting to maintain the functional length of the extremity. Several bone grafting options are available, including the use of a freeze-dried or fresh-frozen femoral head allograft or autograft obtained from the iliac crest or fibula, all of which pose their own inherent risks. The noted complications with massive bone grafting techniques have included graft collapse, infection, immune response, donor site morbidity, and nonunion. In an effort to avoid many of these complications, we present a case report involving post-traumatic talar avascular necrosis in a 59-year-old male who was successfully treated with the use of a porous tantalum spacer, an autogenic morselized fibular bone graft, and 30 mL of bone marrow aspirate in conjunction with a retrograde tibiocalcaneal nail. Porous tantalum is an attractive substitute for bone grafting because of its structural integrity, biocompatibility, avoidance of donor site complications, and lack of an immune response. The successful use of porous tantalum has been well-documented in hip and knee surgery. We present a practical surgical approach to tibiotalocalcaneal arthrodesis with a large segmental deficit. To our knowledge, this is the first published report describing an alternative surgical technique to address global avascular necrosis of the talus that could have additional applications in salvaging the ankle with a large bone deficiency. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Ligamentum teres tenodesis in medial approach open reduction for developmental dislocation of the hip.

PubMed

Bache, Christopher Edward; Graham, H Kerr; Dickens, D Robert V; Donnan, Leo; Johnson, Michael B; Nattrass, Gary; O'Sullivan, Mark; Torode, Ian P

2008-09-01

When closed reduction of a developmental dislocation of the hip fails, some form of open reduction is required. In recent years, the many advantages of the medial approach open reduction have been emphasized. However, there have been suggestions that the rate of growth disturbance in the proximal femur and the requirement for secondary surgical procedures may be higher with this route than with others. The purpose of this study was to investigate the efficacy and safety of a modified medial approach open reduction, in which the stability of the reduction is enhanced by resection of the redundant ligamentum teres and suturing of the stump of the tendon to the anteromedial capsule. The hospital records and radiographs of 92 infants and children with 109 dislocated hips were reviewed retrospectively. Key demographic and pretreatment data were collected by the first author and compared with the outcome at the most recent follow-up. In addition, 69 children returned for a clinical evaluation by the first author. The outcome at the most recent follow-up was graded according to Severin, and associations were sought between pretreatment grade of dislocation according to Tonnis, the presence of ossific nucleus, changes in the acetabular index, the requirements for secondary surgery, associations with previous treatment, and the position of abduction in the postoperative cast. At a mean follow-up of 9 years, 89% of hips were classified as Severin grade 1 or 2. Avascular necrosis (AVN) was classified according to the system of Kalamchi and MacEwen. The incidence of AVN was 41%, but two thirds of these were grade 1 (temporary irregular ossification), and the Severin grading in these hips was not compromised. The presence of ossification in the capital epiphysis and a range of abduction of less than 60 degrees in the hip spica were noted to be protective against the development of AVN. Three hips redislocated and required additional treatment. Thirty-eight hips required a total of 44 additional surgical procedures. We have demonstrated that it is possible to use a medial approach for open reduction of the congenitally dislocated hip in combination with tenodesis of the ligamentum teres to the anteromedial joint capsule. The incidence of growth disturbance in the proximal femur is high and cumulative with long-term follow-up. However, in this large series, the rate of hip stability, growth disturbance, and need for secondary surgery are comparable to other series. We conclude that the many advantages of open reduction by the medial approach outweigh the disadvantages.

Adaptations for marine habitat and the effect of Triassic and Jurassic predator pressure on development of decompression syndrome in ichthyosaurs

NASA Astrophysics Data System (ADS)

Rothschild, B. M.; Xiaoting, Z.; Martin, L. D.

2012-06-01

Decompression syndrome (caisson disease or the "the bends") resulting in avascular necrosis has been documented in mosasaurs, sauropterygians, ichthyosaurs, and turtles from the Middle Jurassic to Late Cretaceous, but it was unclear that this disease occurred as far back as the Triassic. We have examined a large Triassic sample of ichthyosaurs and compared it with an equally large post-Triassic sample. Avascular necrosis was observed in over 15 % of Late Middle Jurassic to Cretaceous ichthyosaurs with the highest occurrence (18 %) in the Early Cretaceous, but was rare or absent in geologically older specimens. Triassic reptiles that dive were either physiologically protected, or rapid changes of their position in the water column rare and insignificant enough to prevent being recorded in the skeleton. Emergency surfacing due to a threat from an underwater predator may be the most important cause of avascular necrosis for air-breathing divers, with relative frequency of such events documented in the skeleton. Diving in the Triassic appears to have been a "leisurely" behavior until the evolution of large predators in the Late Jurassic that forced sudden depth alterations contributed to a higher occurrence of bends.

Adaptations for marine habitat and the effect of Triassic and Jurassic predator pressure on development of decompression syndrome in ichthyosaurs.

PubMed

Rothschild, B M; Xiaoting, Z; Martin, L D

2012-06-01

Decompression syndrome (caisson disease or the "the bends") resulting in avascular necrosis has been documented in mosasaurs, sauropterygians, ichthyosaurs, and turtles from the Middle Jurassic to Late Cretaceous, but it was unclear that this disease occurred as far back as the Triassic. We have examined a large Triassic sample of ichthyosaurs and compared it with an equally large post-Triassic sample. Avascular necrosis was observed in over 15% of Late Middle Jurassic to Cretaceous ichthyosaurs with the highest occurrence (18%) in the Early Cretaceous, but was rare or absent in geologically older specimens. Triassic reptiles that dive were either physiologically protected, or rapid changes of their position in the water column rare and insignificant enough to prevent being recorded in the skeleton. Emergency surfacing due to a threat from an underwater predator may be the most important cause of avascular necrosis for air-breathing divers, with relative frequency of such events documented in the skeleton. Diving in the Triassic appears to have been a "leisurely" behavior until the evolution of large predators in the Late Jurassic that forced sudden depth alterations contributed to a higher occurrence of bends.

Stem Cell Therapy for Avascular Necrosis of Femoral Head in Sickle Cell Disease: Report of 11 Cases and Review of Literature.

PubMed

Sadat-Ali, Mir; Azam, Md Q; Elshabouri, Ezzat M; Tantawy, Ahmad M; Acharya, Sadananda

2017-11-30

Sickle cell disease (SCD) is quite common in eastern Saudi Arabia and Avascular necrosis of femoral head (ANFH) occurs in 30% of the young patients leading to early joint arthroplasty. This study was conducted to assess the benefits of injection of osteoblasts in the avascular lesions of the head of femur. A preset technique was used, 10 CC of bone marrow aspiration was performed under local anesthesia and aseptic technique. Osteoblasts were separated from the bone marrow cells. The avascular area was drilled and 10 million osteoblasts were transplanted at the lesion site. Patients were seen in the out patient clinic after two weeks for removal of the suture and addressed the questionnaire and examined for the range of movement. The follow up MRI was performed at 4 months. The average age was 20.2±3.9 years. The mean hemoglobin S was 81.6±4.8 percent. Quality of Life Score for Chronic Hip Disease was assessed and found at 8.6 (1 being the severe limitation and 10 being normal), whereas Harris hip score improved from 41.7±5.1 to 88.93±3.6 (p < 0.001). MRI of pre and post osteoblast implantation showed robust new bone formation and disappearance of the avascular lesions. The short term results were good and we believe the injection of osteoblast in the avascular lesion of head of femur is a less invasive procedure devoid of any untoward complications and merits such treatment in large patient group with longer follow up.

United Kingdom nationwide study of avascular necrosis of the jaws including bisphosphonate-related necrosis.

PubMed

Rogers, S N; Palmer, N O A; Lowe, D; Randall, C

2015-02-01

We aimed to record all new patients who presented to departments of oral surgery, oral medicine, and oral and maxillofacial surgery, and to dental hospitals in the UK, with avascular necrosis of the jaws including bisphosphonate-related necrosis (BRONJ) over a 2-year period (1 June 2009-31 May 2011). They were eligible irrespective of age, cause, or coexisting conditions. Data on incidence, clinical characteristics, risk factors, and coexisting conditions were collected. A total of 383 cases were registered: 369 were described as BRONJ, 5 as avascular necrosis, and 9 were unknown. Bisphosphonates had been given orally in 207 (56%), intravenously in 125 (34%), both orally and intravenously in 27 (7%), and was unknown in 9 (2%); one had been given denosumab. The main risk factor was dental extraction, and the mandible was commonly affected. The median duration of administration until onset of BRONJ was 3 years in those treated intravenously and 4 years in those treated orally. Levels of engagement with the study varied between regions, and extrapolation from the 2 most involved (Merseyside and Northern Ireland) found around 8.2-12.8 cases/million/year, which is 508-793 patients/year across the UK. To our knowledge this is one of the first studies to estimate national rates of BRONJ. It confirms that the risk and incidence are low. With changes in trends for antiresorptive bone medication, and increasing numbers of elderly people, it would be useful to repeat the registration in the future. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Histopathology of aseptic necrosis of the femoral head in sickle cell disease.

PubMed

Mukisi-Mukaza, Martin; Gomez-Brouchet, Anne; Donkerwolcke, Monique; Hinsenkamp, Maurice; Burny, Franz

2011-08-01

This study compares the histopathology of bone biopsies from patients suffering from sickle cell anaemia (homozygote SS) to heterozygote patients (SA) and homozygotes with aseptic osteonecrosis (AA). The sensitivity to bacterial infection of sickle cell patients raises the question of the aetiology of sepsis in the onset of the necrosis. To our knowledge this study is the first to analyse the histopathology of osteonecrosis of the femoral head, at its early stages, in sickle cell anaemia. At the University Hospital of Pointe-à-Pitre, from 1994 to 2007, 38 bone biopsies were obtained from adult patients with avascular necrosis of the femoral head at the time of a core decompression procedure (SS, SC: 27; AS: 5; AA: 6). The histology of the biopsies confirmed the necrosis; all bacteriological cultures were negative. Patients displaying one S gene (SS, SC, AS) compared to homozygote subjects (AA) showed a significant increase of a nonspecific inflammatory granulomatosis (p = 0.003). No relationship was observed between the radiological stages and the histology whatever the genotype (p = 0.1). Inflammatory histopathology without sepsis or advanced alteration characterises the early stages of sickle cell necrosis. This inflammatory process is absent in idiopathic avascular necrosis.

Dysbaric Osteonecrosis in Divers. 1. A Survey of 611 Selected U. S. Navy Divers

DTIC Science & Technology

1976-02-24

ed., Academic Press, New York, 1971, pp 251- 262. 10 7. Asahi, S. H. Ohiwa, and I. Nashimoto, " Avascular Bone Necrosis in Japanese Diving...bone necrosis has been confirmed. 4>5 The confirmation of aseptic bone necrosis in Caisson workers prompted several studies of divers to determine...de- scribe the radiological observations of bone density and structure variations which appear to be aseptic bone necrosis occurring in

Imaging of Posttraumatic Arthritis, Avascular Necrosis, Septic Arthritis, Complex Regional Pain Syndrome, and Cancer Mimicking Arthritis.

PubMed

Rupasov, Andrey; Cain, Usa; Montoya, Simone; Blickman, Johan G

2017-09-01

This article focuses on the imaging of 5 discrete entities with a common end result of disability: posttraumatic arthritis, a common form of secondary osteoarthritis that results from a prior insult to the joint; avascular necrosis, a disease of impaired osseous blood flow, leading to cellular death and subsequent osseous collapse; septic arthritis, an infectious process leading to destructive changes within the joint; complex regional pain syndrome, a chronic limb-confined painful condition arising after injury; and cases of cancer mimicking arthritis, in which the initial findings seem to represent arthritis, despite a more insidious cause. Copyright © 2017 Elsevier Inc. All rights reserved.

AmBisome Induced Avascular Necrosis of the Alae of the Nose of a very young girl suffering from Kala-azar - a Case Report.

PubMed

Maruf, Shomik; Nath, Proggananda; Aktar, Fatima; Basher, Ariful

2016-12-01

Although liposomal amphotericin B (AmBisome) is considered as the first-line treatment for New Kala-azar, there is not enough evidence on the dosage formulation in children and its effect on them. Being considered as the safest drug for treatment of Kala-azar, this case of AmBisome-induced avascular necrosis now gives rise to the question; whether it is actually safe enough and if a dosage modification is needed in case of children. This so far, to the best of our knowledge, is the first instance of such severe adverse event due to AmBisome administration.

Avascular Necrosis of the Femoral Head.

PubMed

Seijas, Roberto; Sallent, Andrea; Rivera, Eila; Ares, Oscar

2017-12-29

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

G7 BiSpherical Acetabular Shell PMCF Study

ClinicalTrials.gov

2017-11-22

Rheumatoid Arthritis; Osteoarthritis; Noninflammatory Degenerative Joint Disease; Avascular Necrosis; Correction of Functional Deformity; Non-Union Fracture; Femoral Neck Fractures; Trochanteric Fractures

Stem Cell Therapy for Avascular Necrosis of Femoral Head in Sickle Cell Disease: Report of 11 Cases and Review of Literature

PubMed Central

Sadat-Ali, Mir; Azam, Md Q; Elshabouri, Ezzat M; Tantawy, Ahmad M; Acharya, Sadananda

2017-01-01

Background and Objective Sickle cell disease (SCD) is quite common in eastern Saudi Arabia and Avascular necrosis of femoral head (ANFH) occurs in 30% of the young patients leading to early joint arthroplasty. This study was conducted to assess the benefits of injection of osteoblasts in the avascular lesions of the head of femur. Patients and Methods A preset technique was used, 10 CC of bone marrow aspiration was performed under local anesthesia and aseptic technique. Osteoblasts were separated from the bone marrow cells. The avascular area was drilled and 10 million osteoblasts were transplanted at the lesion site. Patients were seen in the out patient clinic after two weeks for removal of the suture and addressed the questionnaire and examined for the range of movement. The follow up MRI was performed at 4 months. Results The average age was 20.2±3.9 years. The mean hemoglobin S was 81.6±4.8 percent. Quality of Life Score for Chronic Hip Disease was assessed and found at 8.6 (1 being the severe limitation and 10 being normal), whereas Harris hip score improved from 41.7±5.1 to 88.93±3.6 (p<0.001). MRI of pre and post osteoblast implantation showed robust new bone formation and disappearance of the avascular lesions. Conclusions The short term results were good and we believe the injection of osteoblast in the avascular lesion of head of femur is a less invasive procedure devoid of any untoward complications and merits such treatment in large patient group with longer follow up. PMID:28844125

A tissue engineering strategy for the treatment of avascular necrosis of the femoral head.

PubMed

Aarvold, A; Smith, J O; Tayton, E R; Jones, A M H; Dawson, J I; Lanham, S; Briscoe, A; Dunlop, D G; Oreffo, R O C

2013-12-01

Skeletal stem cells (SSCs) and impaction bone grafting (IBG) can be combined to produce a mechanically stable living bone composite. This novel strategy has been translated to the treatment of avascular necrosis of the femoral head. Surgical technique, clinical follow-up and retrieval analysis data of this translational case series is presented. SSCs and milled allograft were impacted into necrotic bone in five femoral heads of four patients. Cell viability was confirmed by parallel in vitro culture of the cell-graft constructs. Patient follow-up was by serial clinical and radiological examination. Tissue engineered bone was retrieved from two retrieved femoral heads and was analysed by histology, microcomputed tomography (μCT) and mechanical testing. Three patients remain asymptomatic at 22- to 44-month follow-up. One patient (both hips) required total hip replacement due to widespread residual necrosis. Retrieved tissue engineered bone demonstrated a mature trabecular micro-architecture histologically and on μCT. Bone density and axial compression strength were comparable to trabecular bone. Clinical follow-up shows this to be an effective new treatment for focal early stage avascular necrosis of the femoral head. Unique retrieval analysis of clinically translated tissue engineered bone has demonstrated regeneration of tissue that is both structurally and functionally analogous to normal trabecular bone. Copyright © 2013 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

Progression of Ocular Sulfur Mustard Injury: Development of a Model System

DTIC Science & Technology

2010-01-01

corneal sequelae include epithelial erosions, necrosis , and corneal inflammation. Longer term, a progressive injury becomes distributed throughout the...between 1 and 4 min of vapor delivery (Supporting Fig. SI; R2 > 0.98). Because the stroma is predominantly avascular , the mechanism by which SM:protein...after exposure Corneal epilhelial necrosis Sbomal necrosis Figure 2. Longitudinal measurements of corneal thickness, neutrophil infiltration, and

A rare case of avascular necrosis in sickle cell trait: a case report.

PubMed

Sanders, William J

2018-01-01

Sickle cell trait is usually an asymptomatic presentation of a patient with slightly different hemoglobin molecule makeup than normal. It is similar to a more serious disease, sickle cell disease, in which a person's hemoglobin is mutated in such a way that causes their red blood cells to easily change shape in certain environmental and internal states; this causes red blood cells to adhere to the walls and occlude the lumen of the arteries in which they travel, leading to downstream effects secondary to ischemia. Sickle cell trait does not have these ischemic effects, usually. In this case, a young African American female patient presents to the clinic with severe right hip pain. Her past medical history includes sickle cell trait and asthma. She has not been symptomatic of her asthma for years and is not on therapy for it. The pain has lasted for several months and has not improved with anti-inflammatory medication. There is severe pain with internal and external rotation of the hip. The neurovascularity of the lower extremities is intact bilaterally. MRI of the femur shows stage 2 or 3 avascular necrosis of the femoral head, while X-rays of the femur are unremarkable. Non weight-bearing for several weeks was unsuccessful; shortly thereafter, the patient underwent core decompression of the right femoral head as well as starting bisphosphonates. The patient improved temporarily but regressed shortly thereafter. Her avascular necrosis worsened radiographically over the next several months. At this point, the only other option would be to do a total hip arthroplasty, but the patient may need several more throughout her lifetime due to the lifespan of the artificial replacement. There have only been scarce reports of avascular necrosis in patients with sickle cell trait. This manuscript presents such a case and includes the trials and tribulations associated with its management.

Modified Pauwels' intertrochanteric osteotomy in neglected femoral neck fractures in children: a report of 10 cases followed for a minimum of 5 years.

PubMed

Magu, Narender Kumar; Singh, Roop; Sharma, Ashwini Kumar; Ummat, Vikas

2007-04-01

To evaluate the role of a modified Pauwels' intertrochanteric osteotomy (MPIO) in neglected femoral neck fractures in children. Prospective study with retrospective analysis. Tertiary care Postgraduate Institute of Medical Sciences. Ten children (8 males, 2 females) with an average age of 10.2 years with neglected femoral neck fractures were seen from 1990 to 1998. A femoral neck fracture was considered neglected when no proper medical treatment was instituted for at least 1 month following the fracture. Nonunion was accompanied by coxa vara and resorption of the femoral neck in 9 patients; a 10th patient had a neglected femoral neck fracture for 1 month without coxa vara. Three patients at time of presentation with Delbet Type II displaced fractures with associated nonunion and coxa vara (2 with Ratliff Type III and 1 with Type I) also had avascular necrosis using plain radiographic criteria of increased density. Modified Pauwels' intertrochanteric osteotomy. The children were immobilized in a hip spica for 6-10 weeks postoperatively and weightbearing was started after hip spica removal. Fracture healing, neck-shaft angle, avascular necrosis, and functional outcome. Patients were followed for an average of 8.2 years (range 5-12 years). All patients had union of their fracture within an average of 16.6 weeks (12-20 weeks) and of the osteotomy site within 8.2 weeks (7-9 weeks). Radiologic signs of avascular necrosis disappeared completely in the 3 patients who presented with avascular necrosis. In 1 patient with a preoperatively viable femoral head, radiologic signs of Ratliff Type I avascular necrosis appeared between 60 and 98 weeks. This radiologic finding became normal again, indicating viability of the femoral head somewhere between 98 to 205 weeks of follow-up. Postoperatively, an average of 135-degree neck-shaft angle was achieved (range 125-160 degrees). The average preoperative neck-shaft angle was 104.4 degrees (range 92-120 degrees) and on the normal hip side it was 127.7 degrees (range 124-132 degrees). Significant improvement in the neck-shaft angle was seen compared with the preoperative angle (P < 0.001) and normal hip angle (P < 0.05). Coxa vara and signs of chondrolysis were not observed in any of the patients. Premature proximal femoral epiphyseal closure resulting in a 1-cm and a 1.5-cm leg-length discrepancy was seen in 2 patients as compared with their normal side. A mild Trendelenburg gait was observed in 1 patient (10%). Using Ratliff's criteria, 9 patients (90%) were graded as a good result and 1 patient (10%) was graded as a fair result. The osteotomy plate was removed in 1 patient (10%). An MPIO creates a biomechanical environment conducive to healing of a neglected femoral neck nonunion in a child while simultaneously correcting an associated coxa vara. The procedure also seems to have a biological role in helping restore viability to a noncollapsed femoral head with avascular necrosis.

[The role of core decompression for the treatment of femoral head avascular necrosis in renal transplant recipients].

PubMed

Zivcić-Cosić, Stela; Stalekar, Hrvoje; Mamula, Mihaela; Miletić, Damir; Orlić, Lidija; Racki, Sanjin; Cicvarić, Tedi

2012-10-01

Avascular bone necrosis is a relatively rare but significant complication in renal transplant recipients because it causes progressive pain and invalidity. It can be the consequence of the action of numerous causative factors, but it is mostly connected to corticosteroid treatment.The underlying pathophysiologic mechanism is a diminished blood flow to the bone leading to necrosis and bone destruction. During the past 25-years period, 570 renal transplantations and five combined kidney and pancreas transplantations were performed in our centre. A part of the patients was lost to follow-up due to the separation of Croatia from the former Republic of Yugoslavia. After transplantation, we revealed aseptic necrosis of the femoral head in five female patients. All patients had a history of treatment with pulse doses of corticosteroids. At transplantation the average age of the patients was 52.2 yrs (range 46 to 62 yrs), and dialytic treatment before transplantation lasted in average 9.2 yrs (range 2.5 to 21.2 yrs). The period between renal transplantation and the development of clinical signs of avascular bone necrosis lasted in average 1.2 yrs (range 0.3 to 2.3 yrs). We will demonstrate our 62-year old female patient with terminal renal failure caused by post-streptococcal glomerulonephritis, who was treated with peritoneal dialysis 2.5 years before renal transplantation. Twenty months before renal transplantation the patient received pulse doses of corticosteroids, together with immunoglobulins and plasmapheresis, for the treatment of an acute polyradiculoneuritis Guillaine Barré. After transplantation a standard immunosuppressive protocol was applied which included tacrolimus, mycophenolate mofetil, corticosteroids and induction with basiliximab. Four months after transplantation the patient started to feel pain in the right hip after longer standing, in addition to the earlier long-lasting problems caused by bilateral coxarthrosis. The pelvic radiograph showed subchondral radiolucencies in the lateral part of the head circumference spreading into the proximal part of the neck of the right femur, which indicated the presence of aseptic necrosis, but these changes could have also been caused by coxarthrosis. Unexpectedly, magnetic resonance imaging (MRI) did not reveal changes characteristic for avascular bone necrosis. Due to the progressively worsening of pain and the radiographic finding, the patient was submitted to decompression surgery of the femoral head. The surgical procedure was performed under diascopic guidance (C-arm) which allowed the correct positioning of a Kuerschner wire. A cannulated drill (diameter 4.0 mm) was placed over the wire and we performed two drillings of the spongiosis of the femoral head through to the subchondral area. Postoperatively, the patient was soon verticalized and advised to walk with crooks during a period of six weeks. This time is necessary to allow the mineralisation and strengthening of the bone which is now better vascularised. The patient recovered well and had no more pain. In renal transplant recipients it is most important to raise suspicion and verify the presence of avascular bone necrosis early, because timely bone decompression surgery can eliminate pain and cure the patient or it can prevent or delay bone destruction. When clinical signs of avascular bone necrosis arise and radiographic or standard MRI findings are negative, additional investigations (i.e. SPECT or MRI with contrast) should be performed to confirm or exclude the diagnosis. In latter phases of the disease, surgical decompression of the femoral head cannot lead to permanent amelioration, and it is inevitable to perform more invasive surgical procedures like "resurfacing" or bone grafting in younger patients, or the implantation of total hip endoprotheses.

[Acute traumatic and especially neglected traumatic hip dislocations are very rare in children].

PubMed

Fernandez, F F; Wirth, T; Eberhardt, O

2012-09-01

We report about the first hip arthroscopies of extracapsular neglected hip dislocations with concomitant injuries in two children (2 and 4 years old). The major problem of traumatic hip dislocation is avascular necrosis. Further problems are possible concomitant injuries. It is important not to cause further damage by therapeutic procedures. In a 4-year-old child the hip could be reduced under visualization and in a 2-year-old child with epiphyseal fracture the extent of the operation could be reduced. In both children large avulsion injuries of the ligamentum capitis femoris could be resected via hip arthroscopy. Hip arthroscopy can reduce surgical morbidity considerably and can possibly contribute to prevention of the feared avascular necrosis of the femoral head.

Angiogenesis and Therapeutic Approaches to NF1 Tumors

DTIC Science & Technology

2007-04-01

corneal neovascularization model was developed. In this model, the avascularity of the cornea highly facilitates the quantification of neovascularture...wild-type corneas in avascular area. However, in the NV zone, the number of macrophage was 4.6-fold greater in Nf1þ /– corneas than wild-type corneas...GEM tumor classification because of low cellularity and no necrosis . They exceed that clas- sification, however, due to their low to moderate prolif

Soft Tissue Wounds and Principles of Healing

DTIC Science & Technology

2007-01-01

PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 source you read. This layer is avascular , and the classically...other materials across the dermal– epidermal junction. Because the epidermis is avascular , it depends upon diffusion from the capillary beds of the dermis...Full-thickness skin loss involving damage or necrosis of sub- cutaneous tissue that may extend down to but not through the under- lying fascia. STAGE 4

Aseptic Bone Necrosis Among U.S. Navy Divers: Survey of 934 Nonrandomly Selected Personnel

DTIC Science & Technology

1977-06-01

Health, Education, and Welfare, Washington, D.C. Kawashima, M., T. Torisu, K. Hayashi, and Y. Kamo. 1974. Avascular bone necrosis in Japanese diving...5ÜL ^4- P=- 7 RESEM^a^ATORY SUBMARINE BASE, GROTON, CONN. REPORT NUMBER 854 ASEPTIC BONE NECROSIS AMONG U. S. NAVY DIVERS: Survey of 934...Approved for public release; distribution unlimited SUMMARY PAGE THE PROBLEM Aseptic boire~ necrosis tABN) has beelTknown toT5e~ associated with

A Modification of the Dunn Osteotomy With Preservation of the Ligamentum Teres.

PubMed

Bali, Navi; Harrison, James; Laugharne, Edward; Bache, C Edward

2017-06-01

We aimed to determine if a modified Dunn osteotomy could be safely performed without surgical dislocation and consequent preservation of the ligamentum teres. All patients undergoing a modified Dunn osteotomy for a slipped capital femoral epiphysis over an 8-year period were included in this study, and all had a severe slip with an open physis. The modified Dunn procedure was performed on 34 hips in 34 patients. The mean age was 13.1 years (range, 11 to 16 y) with a mean follow-up time of 54 months (range, 15 to 102 mo). All slips were severe (grade 3) with a mean slip angle of 73.2 degrees (range, 60 to 90 degrees). Nineteen slips were stable and 15 were unstable. Of the unstable slips, the average time from initial presentation to the emergency department until surgery was 9.4 days (range, 2 to 42 d). Excluding 1 patient who developed complete collapse of the femoral head (NAHS 56), the average Nonarthritic Hip score was 98 (range, 93.7 to 100). Four (11.8%) patients developed avascular necrosis of the femoral head, of which 3 were unstable slips. A modified Dunn osteotomy with preservation of the ligamentum teres allows an excellent restoration of the anatomic alignment of the femoral head and neck. Rates of AVN are not increased compared with other techniques of subcapital osteotomy but this complication cannot be eliminated particularly in patients with unstable slips. Level III.

An Evaluation of the Softperm Contact Lens in the Simulated Aircraft Environment

DTIC Science & Technology

1991-01-01

potential effect on the eye of low atmospheric pressure and resultant low oxygen pressure that occurs with increased altitude. The cornea, which is avascular ... avascularity as well as its morphology and chemical composition. The epithelial cells are not keratinized and their components have a uniform index of refraction...noted that cell damage and/or necrosis was much less likely to occur if cellular swelling does not occur. They observed no epithelial staining in their

Italian experience on use of E.S.W. therapy for avascular necrosis of femoral head.

PubMed

Russo, Sergio; Sadile, Francesco; Esposito, Roberto; Mosillo, Giuseppe; Aitanti, Emanuele; Busco, Gennaro; Wang, Ching-Jen

2015-12-01

Osteonecrosis (avascular necrosis) of the femoral head is a clinical disease due to a severe bone vascular alteration associated with intense pain and loss of joint function, with an incidence of 0.1% and unknown aetiology. Many classifications exist to describe it and in the final stages the patient will need a total hip arthroplasty. In the early stages, ESWT has given excellent responses.
 The Neapolitan school studied more than 600 patients who had very good results in I and II stages of Ficat and Arlet Classification, with an improve of outcomes in VAS and HSS scores. Moreover it has shown a complete restoration of the signal intensity of the femoral head in MRI. Copyright © 2015. Published by Elsevier Ltd.

Treatment for avascular necrosis of bone in people with sickle cell disease.

PubMed

Martí-Carvajal, Arturo J; Solà, Ivan; Agreda-Pérez, Luis H

2014-07-10

Avascular necrosis of bone is a frequent and severe complication of sickle cell disease and its treatment is not standardised. To determine the impact of any surgical procedure compared with other surgical interventions or non-surgical procedures, on avascular necrosis of bone in people with sickle cell disease in terms of efficacy and safety. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Additional trials were sought from the reference lists of papers identified by the search strategy.Date of the most recent search of the Group's Haemoglobinopathies Trials Register: 17 March 2014. Randomised clinical trials comparing specific therapies for avascular necrosis of bone in people with sickle cell disease. Each author independently extracted data and assessed trial quality. Since only one trial was identified, meta-analysis was not possible. One trial (46 participants) was eligible for inclusion. After randomisation eight participants were withdrawn, mainly because they declined to participate in the trial. Data were analysed for 38 participants at the end of the trial. After a mean follow up of three years, hip core decompression and physical therapy did not show clinical improvement when compared with physical therapy alone using the score from the original trial (an improvement of 18.1 points for those treated with intervention therapy versus an improvement of 15.7 points with control therapy). There was no significant statistical difference between groups regarding major complications (hip pain, relative risk (RR) 0.95 (95% confidence interval (CI) 0.56 to 1.60; vaso-occlusive crises, RR 1.14 (95% CI 0.72 to 1.80; very low quality of evidence); and acute chest syndrome, RR 1.06 (95% CI 0.44 to 2.56; very low quality of evidence)). This trial did not report results on mortality or quality of life. We found no evidence that adding hip core decompression to physical therapy achieves clinical improvement in people with sickle cell disease with avascular necrosis of bone compared to physical therapy alone. However, we highlight that our conclusion is based on one trial with high attrition rates. Further randomised controlled trials are necessary to evaluate the role of hip-core depression for this clinical condition. Endpoints should focus on participants' subjective experience (e.g. quality of life and pain) as well as more objective 'time-to-event' measures (e.g. mortality, survival, hip longevity). The availability of participants to allow adequate trial power will be a key consideration for endpoint choice.

Treatment for avascular necrosis of bone in people with sickle cell disease.

PubMed

Martí-Carvajal, Arturo J; Solà, Ivan; Agreda-Pérez, Luis H

2016-08-09

Avascular necrosis of bone is a frequent and severe complication of sickle cell disease and its treatment is not standardised. This is an update of a previously published Cochrane Review. To determine the impact of any surgical procedure compared with other surgical interventions or non-surgical procedures, on avascular necrosis of bone in people with sickle cell disease in terms of efficacy and safety. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Additional trials were sought from the reference lists of papers identified by the search strategy.Date of the most recent search of the Group's Haemoglobinopathies Trials Register: 27 May 2016. Randomized clinical trials comparing specific therapies for avascular necrosis of bone in people with sickle cell disease. Each author independently extracted data and assessed trial quality. Since only one trial was identified, meta-analysis was not possible. One trial (46 participants) was eligible for inclusion. After randomization eight participants were withdrawn, mainly because they declined to participate in the trial. Data were analysed for 38 participants at the end of the trial. After a mean follow up of three years, hip core decompression and physical therapy did not show clinical improvement when compared with physical therapy alone using the score from the original trial (an improvement of 18.1 points for those treated with intervention therapy versus an improvement of 15.7 points with control therapy). There was no significant statistical difference between groups regarding major complications (hip pain, risk ratio 0.95 (95% confidence interval 0.56 to 1.60; vaso-occlusive crises, risk ratio 1.14 (95% confidence interval 0.72 to 1.80; very low quality of evidence); and acute chest syndrome, risk ratio 1.06 (95% confidence interval 0.44 to 2.56; very low quality of evidence)). This trial did not report results on mortality or quality of life. We found no evidence that adding hip core decompression to physical therapy achieves clinical improvement in people with sickle cell disease with avascular necrosis of bone compared to physical therapy alone. However, we highlight that our conclusion is based on one trial with high attrition rates. Further randomized controlled trials are necessary to evaluate the role of hip-core depression for this clinical condition. Endpoints should focus on participants' subjective experience (e.g. quality of life and pain) as well as more objective 'time-to-event' measures (e.g. mortality, survival, hip longevity). The availability of participants to allow adequate trial power will be a key consideration for endpoint choice.

Case report 775. Canine osteosarcoma with associated avascular necrosis and sequestrum formation.

PubMed

De Smet, A A; Dueland, R T; Dubielzig, R R

1993-01-01

A young dog was found to have an osteosarcoma of the proximal femur containing a radiologically evident sequestrum of dead bone. Although the tumor was extensive, the plain films were most remarkable for the presence of a sequestrum. MR scans revealed the extent of the lesion, with low signal throughout the lesion consistent with the heavily calcified tumor and central avascular bone. At the 1-year follow-up, lung metastases had developed, but the dog appeared well.

Arthroscopic Partial Capitate Resection for Type Ia Avascular Necrosis: A Short-Term Outcome Analysis.

PubMed

Shimizu, Takamasa; Omokawa, Shohei; del Piñal, Francisco; Shigematsu, Koji; Moritomo, Hisao; Tanaka, Yasuhito

2015-12-01

To examine short-term clinical results of arthroscopic partial resection for type Ia avascular necrosis of the capitate. Patients who underwent arthroscopic treatment for type 1a avascular necrosis of the capitate with at least 1-year follow-up were identified through a retrospective chart review. The necrotic capitate head was arthroscopically resected with removal of the lunate facet and preservation of the scaphoid and hamate facets. Wrist range of motion, grip strength, and radiographic parameters--carpal height ratio, radioscaphoid angle, and radiolunate angle-were determined before surgery and at the latest follow-up. Patients completed a visual analog scale for pain; Disabilities of the Arm, Shoulder, and Hand measure; and the Patient-Rated Wrist Evaluation score before surgery and at the latest follow-up. Five patients (1 male, 4 females) with a mean age of 34 years (range, 16-49 years) and a mean follow-up duration of 20 months (range, 12-36 months) were identified during the chart review. All were type Ia (Milliez classification). Arthroscopy revealed fibrillation or softening with cartilage detachment at the lunate facet of the capitate head and an intact articular surface at the scaphoid and hamate facet. At the latest follow-up, the mean wrist flexion-extension was 123° (vs 81° before surgery) and grip strength was 74% (vs 37% before surgery). The visual analog scale score for pain; the Disabilities of the Arm, Shoulder, and Hand score; and the Patient-Rated Wrist Evaluation score before surgery showed a significant improvement following treatment. Radiographic parameters did not significantly change at the final follow-up, although the proximal carpal row trended toward flexion. Arthroscopic partial resection of the capitate head was an acceptable treatment for type Ia avascular necrosis of the capitate. It provided adequate pain relief and improved the range of wrist motion and grip strength during short-term follow-up. Therapeutic IV. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Anatomy of the Le Fort I segment: Are arterial variations a potential risk factor for avascular bone necrosis in Le Fort I osteotomies?

PubMed

Bruneder, Simon; Wallner, Jürgen; Weiglein, Andreas; Kmečová, Ĺudmila; Egger, Jan; Pilsl, Ulrike; Zemann, Wolfgang

2018-05-02

Osteotomies of the Le Fort I segment are routine operations with low complication rates. Ischemic complications are rare, but can have severe consequences that may lead to avascular bone necrosis of the Le Fort I segment. Therefore the aim of this study was to investigate the blood supply and special arterial variants of the Le Fort I segment responsible for arterial hypoperfusion or ischemic avascular necrosis after surgery. The arterial anatomy of the Le Fort I segment's blood supply using 30 halved human cadaver head specimens was analyzed after complete dissection until the submicroscopic level. In all specimens the arterial variants of the Le Fort I segment and also the arterial diameters measured at two points were evaluated. The typical known vascularization pattern was apparent in 90% of all specimens, in which the ascending palatine (D1: 1,2 mm ± 0,34 mm; D2: 0,8 mm ± 0,34 mm) and ascending pharyngeal artery (D1: 1,3 mm ± 0,58 mm; D2: <0,4 mm) were both supplying the Le Fort I segment. However in 10% of all specimens, the Le Fort I segment was dependent on the ascending pharyngeal artery alone and the missing ascending palatine artery was replaced with the anterior branch of the ascending pharyngeal artery (D1: 1,9 mm ± 0,32; D2: 1,0 mm ± 0,3 mm). This study is the first description of a special type of arterial variation of the Le Fort I segment. The type of this arterial variation, its clinical relevance and potential consequences are explained. Individuals with this special arterial anatomy may clinically be at a high risk for hypoperfusion and avascular segment necrosis after surgery. An individualized operation plan may prevent ischemic complications in at-risk patients. Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Use of Intraoperative Temporary Invasive Distraction to Reduce a Chronic Talar Neck Fracture-Dislocation

DTIC Science & Technology

2011-04-01

tures. J Orthop Trauma. 2004;18(5):265-270. 2. Metzger M, Levin J, Clancy J. Talar neck frac- tures and rates of avascular necrosis . J Foot Ankle Surg...of the talus.4 Given the risk for osteo- necrosis with talar neck fractures, early operative intervention is con- sidered the standard of care.5

Clinical Evaluation of the TITAN™ Total Shoulder System

ClinicalTrials.gov

2018-02-14

Arthritis; Arthritis, Degenerative; Rheumatoid Arthritis; Post-traumatic Arthrosis of Other Joints, Shoulder Region; Rotator Cuff Syndrome of Shoulder and Allied Disorders; Fracture; Avascular Necrosis; Joint Instability; Joint Trauma; Dislocation, Shoulder; Pain, Shoulder

Multiple Small Diameter Drillings Increase Femoral Neck Stability Compared with Single Large Diameter Femoral Head Core Decompression Technique for Avascular Necrosis of the Femoral Head.

PubMed

Brown, Philip J; Mannava, Sandeep; Seyler, Thorsten M; Plate, Johannes F; Van Sikes, Charles; Stitzel, Joel D; Lang, Jason E

2016-10-26

Femoral head core decompression is an efficacious joint-preserving procedure for treatment of early stage avascular necrosis. However, postoperative fractures have been described which may be related to the decompression technique used. Femoral head decompressions were performed on 12 matched human cadaveric femora comparing large 8mm single bore versus multiple 3mm small drilling techniques. Ultimate failure strength of the femora was tested using a servo-hydraulic material testing system. Ultimate load to failure was compared between the different decompression techniques using two paired ANCOVA linear regression models. Prior to biomechanical testing and after the intervention, volumetric bone mineral density was determined using quantitative computed tomography to account for variation between cadaveric samples and to assess the amount of bone disruption by the core decompression. Core decompression, using the small diameter bore and multiple drilling technique, withstood significantly greater load prior to failure compared with the single large bore technique after adjustment for bone mineral density (p< 0.05). The 8mm single bore technique removed a significantly larger volume of bone compared to the 3mm multiple drilling technique (p< 0.001). However, total fracture energy was similar between the two core decompression techniques. When considering core decompression for the treatment of early stage avascular necrosis, the multiple small bore technique removed less bone volume, thereby potentially leading to higher load to failure.

Bone density loss after allogeneic hematopoietic stem cell transplantation: a prospective study.

PubMed

Stern, J M; Sullivan, K M; Ott, S M; Seidel, K; Fink, J C; Longton, G; Sherrard, D J

2001-01-01

The incidence and course of bone density abnormalities following hematopoietic stem cell transplantation are poorly understood and complicated by the impact of multiple factors. Hip, spine, and wrist bone mineral densities (BMDs) were measured in 104 adults (54 women, 54 men; mean age, 40 years [range, 18-64 years]) at 3 and 12 months after allogeneic transplantation. Clinical and laboratory variables were evaluated using univariate and multivariate analyses to determine risk factors for osteoporosis, fracture, and avascular necrosis. At 3 months posttransplantation, combined (male and female) hip, spine, and wrist z scores were -0.35, -0.42, and +0.04 standard deviations, respectively. At 12 months both men and women experienced significant loss of hip BMD (4.2%, P < .0001); changes in the spine and wrist were minimal. The cumulative dose and number of days of glucocorticoid therapy and the number of days of cyclosporine or tacrolimus therapy showed significant associations with loss of BMD; age, total body irradiation, diagnosis, and donor type did not. Nontraumatic fractures occurred in 10.6% of patients and avascular necrosis in 9.6% within 3 years posttransplantation. The decrease in height between pretransplantation and 12 months posttransplantation was significant (P = .0001). Results indicate that loss of BMD after allogeneic stem cell transplantation is common and accelerated by the length of immunosuppressive therapy and cumulative dose of glucocorticoid. An increased incidence of fracture and avascular necrosis may adversely impact long-term quality of life. Prevention of bone demineralization appears warranted after stem cell transplantation.

Imaging Characteristics of Tenosynovial and Bursal Chondromatosis

DTIC Science & Technology

2010-01-01

presence of tumor staining ( avascular , hypovascular, or hypervascular), the degree (mild, moderate, or marked) and pattern (diffuse or Skeletal Radiol...chondromatosis (T or B), and location of the lesion Skeletal Radiol fluid levels) or central necrosis (low attenuation with rim enhancement). The...enhancement following intravenous contrast if available) or central necrosis (low signal on T1, high signal on T2 with rim enhancement following intravenous

Different Recipient Vessels for Free Microsurgical Fibula Flaps in the Treatment of Avascular Necrosis of the Femoral Head: A Systematic Review and Meta-analysis.

PubMed

Tu, Yiji; Chen, Zenggan; Lineaweaver, William Charles; Zhang, Feng

2017-12-01

Several recipient vessels can be used in free microsurgical fibula flaps (MFFs) for the treatment of avascular necrosis of the femoral head (ANFH). Few articles investigate the influence of different recipient vessels on outcomes of MFF for ANFH. A comprehensive literature search of databases including PubMed-Medline, Ovid-Embase, and Cochrane Library was performed to collect the related studies. The Medical Subject Headings used were "femur head necrosis" and "bone transplantation." The relevant words in title or abstract included but not limited to "fibula flap," "fibular flap," "vascularized fibula," "vascularized fibular," "free fibula," "free fibular," "femoral head necrosis," "avascular necrosis of femoral head," and "ischemic necrosis of femoral head." The methodological index for nonrandomized studies was adopted for assessing the studies included in this review. Finally, 15 studies encompassing a total of 1267 patients (1603 hips) with ANFH were pooled in the overall analysis. Recipient vessels for MFF included the ascending branch of the lateral circumflex femoral artery and vein in 8 studies, descending branch of the lateral circumflex femoral artery and vein in 2 studies, second perforating branch of the deep femoral artery and vein in 4 studies, and inferior gluteal artery and vein in 1 study. Preoperative and postoperative average Harris hip score and pooled analyses of the rate of conversion, radiographic progression, and hip surgery-related complications showed no significant difference on the outcomes of MFF on ANFH between using different recipient vessels. Different recipient vessels did not affect outcomes in MFF procedures for ANFH. High-quality randomized controlled trials and prospective studies would be necessary to clarify reliable advantages and disadvantages between different recipient vessels. Until then, surgeons are justified in using ascending branch of the lateral circumflex femoral artery and vein, descending branch of the lateral circumflex femoral artery and vein, second perforating branch of the deep femoral artery and vein, and inferior gluteal artery and vein vessels according to care circumstances and customary practice.

A Multi-centre Study to Assess the Long-term Performance of the Summit™ Hip in Primary Total Hip Replacement

ClinicalTrials.gov

2016-08-03

Rheumatoid Arthritis; Osteoarthritis; Post-traumatic Arthritis; Collagen Disorders; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis

Analysis of functional outcome of Hoffa fractures: A retrospective review of 32 patients.

PubMed

Trikha, Vivek; Das, Saubhik; Gaba, Sahil; Agrawal, Prabhat

2017-01-01

Hoffa fractures are uncommon intra-articular fractures of femoral condyle in coronal plane. The purpose of our study is to assess radiologic and functional outcome in operatively treated Hoffa fractures. We retrospectively reviewed 32 patients of isolated Hoffa fracture from January 2010 to March 2015. All were treated with open reduction and internal fixation using lateral approach for lateral Hoffa and medial approach for medial Hoffa fracture. Cancellous screws in lag mode and/or antiglide plate were employed for fixation in accordance with fracture anatomy. All patients were subjected to aggressive physical therapy postoperatively. Knee Society Score (KSS), International Knee Documentation Committee Score (IKDC), and Knee range of motion (ROM) were documented at final follow-up for functional evaluation. All fractures united by mean time of 11.56 ± 1.5 weeks. No evidence of subsequent displacement or fixation failure, arthritis, Avascular necrosis (AVN) of femoral condyle was elicited in any of the patients. Documented mean KSS and mean IKDC Score at final follow-up were 83.19 ± 8.43 and 81.62± 6.95, respectively. ROM at final follow-up was ranging from 0° to mean 116.41° ± 13.98°. Complications included stiffness of the involved knee in four patients, including one patient who developed infection and had to undergo implant removal after fracture union. Operative treatment of Hoffa fractures yields fairly good functional outcome. One must endeavor to achieve adequate intraoperative exposure and stable congruous articular reconstruction. Early aggressive physical therapy is a harbinger of optimal outcome.

Outcome of total hip arthroplasty for avascular necrosis of the femoral head in systemic lupus erythematosus.

PubMed

Woo, Min Su; Kang, Joon Soon; Moon, Kyoung Ho

2014-12-01

This study evaluated the result of total hip arthroplasty (THA) for avascular necrosis of the femur head (AVNFH) in systemic lupus erythematosus (SLE) patients. Nineteen THAs were performed on 13 patients with SLE. The results of these patients were compared with the results of the control group (19 patients) who had THR due to AVNFH with none-SLE conditions. The Harris hip score increased from a preoperative average of 65.3 points to 94.9 at the most recent follow-up. In the control group, the mean HHS was 67.2 preoperatively and 96.1 postoperatively at the last follow-up. No significant difference was found between SLE patients and non-SLE patients who underwent hip arthroplasty. In conclusion, THA is an acceptable treatment for achieving functional improvement in patients who had SLE and AVNFH. Copyright © 2014 Elsevier Inc. All rights reserved.

Radiographic followup of joints injected with triamcinolone hexacetonide for the management of childhood arthritis.

PubMed

Sparling, M; Malleson, P; Wood, B; Petty, R

1990-06-01

Evidence of deleterious effects following intraarticular injection of triamcinolone hexacetonide was sought through a review of radiographs of 145 joints of 55 children with chronic arthritis. Possible deleterious effects were noted in 16 joints of 11 patients. These effects included: small patella (2 joints), patellar osteochondritis dissecans (1 joint), periarticular calcification (9 joints), intraarticular tibial bony spur (1 joint), avascular necrosis of the distal radial epiphysis (2 joints), and avascular necrosis of the proximal femoral epiphysis (1 joint). Only the latter possible complication was symptomatic. Serial radiographs of 76 joints of 30 children showed mild progressive changes compatible with the underlying disease, except in the hip joint, where changes were more severe. The intraarticular injection of triamcinolone hexacetonide is a procedure that appears to be associated with an acceptably low frequency of radiologic abnormalities for many joints in children with chronic arthritis, but its effects on the hip joint remain uncertain.

Genetically Engineered Autologous Cells for Antiangiogenic Therapy of Breast Cancer

DTIC Science & Technology

2004-07-01

consisted of a large, fragmented avascular center surrounded by a thin band of vascularized matrix material, itself covered by a capsule of connective tissue...contained dead cells that showed features of coagulation necrosis . The minimal inflammatory response consisted of neutrophils scattered within the...vascularize most likely contributed to the death (coagulation necrosis ) of implanted MSCs localized in the implant core and to the fragmentation of the

The Role of Myoepithelial Maspin in Breast Carcinoma Progression Diagnosis and Screening

DTIC Science & Technology

2003-08-01

expression pro- xenografts, the tumors were essentially avascular and their filing (gene chip analysis) to see whether the different myo- 116 S.H. Barskv...factor; aFGF, acidic fibroblast growth factor; TFGa, transforming growth factor a; TGFP3. transforming growth factor 03; TNFa, tumor necrosis factor a...angiogenesis but containing bound angiogenic inhibitors. These myoepithelial xenografts exhibit only minimal hypoxia but extensive necrosis compared with their

Management of Nonunited Talar Fractures With Avascular Necrosis by Resection of Necrotic Bone, Bone Grafting, and Fusion With an Intramedullary Nail.

PubMed

Abd-Ella, Mohamed Mokhtar; Galhoum, Ahmed; Abdelrahman, Amr Farouk; Walther, Markus

2017-08-01

The presence of nonunion of a talar fracture with displacement, together with complete avascular necrosis, is a challenging entity to treat. Twelve patients, 8 men (66.7%) and 4 women (33.3%), with nonunited talar fractures and extensive avascular necrosis of the talus were included. The average age was 27.7 years (range, 19-38 years). After exclusion of infection, the patients underwent resection of necrotic bone, bulk autograft, and fusion using an intramedullary nail. The posterior approach was used in 11 patients and the anterior approach in 1 patient. The primary outcome was solid osseous union at the ankle and subtalar level and between the talar head anteriorly and the posterior construct, as evidenced by computed tomographic examination. Functional assessment was performed with the American Orthopaedic Foot & Ankle Society score and subjective patient satisfaction Results: After a mean follow-up duration of 23 months (range, 12-60 months), solid osseous union was achieved in 8 patients (66.7%). Stable fibrous union was seen in 1 patient (8.3%). Three patients (25%) required reoperation, and osseous fusion was finally achieved. American Orthopaedic Foot & Ankle Society score improved from a mean of 39.3 (range, 12-56) preoperatively to 76.6 (range, 62-86) at last follow-up. Subjective patient satisfaction was graded good or excellent in all cases. Resection of necrotic talar body and bulk autograft with tibiotalocalcaneal fusion by an intramedullary nail through a posterior approach was a reasonable option for the management of type IV posttraumatic talar deformity. Level IV, case series.

A Two Centre Study to Assess the Stability and Long-term Performance of the C-Stem™ AMT in a Total Primary Hip Replacement

ClinicalTrials.gov

2017-06-23

Rheumatoid Arthritis; Osteoarthritis; Post-traumatic Arthritis; Collagen Disorders; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis

A Randomised Single Centre Study to Compare the Long-term Wear Characteristics of Marathon™ and Enduron™ Polyethylene Cup Liners in Primary Total Hip Replacement

ClinicalTrials.gov

2017-06-23

Osteoarthritis; Post-traumatic Arthritis; Collagen Disorders; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis

Synthesis of avenanthramides using engineered Escherichia coli.

PubMed

Lee, Su Jin; Sim, Geun Young; Kang, Hyunook; Yeo, Won Seok; Kim, Bong-Gyu; Ahn, Joong-Hoon

2018-03-22

Hydroxycinnamoyl anthranilates, also known as avenanthramides (avns), are a group of phenolic alkaloids with anti-inflammatory, antioxidant, anti-itch, anti-irritant, and antiatherogenic activities. Some avenanthramides (avn A-H and avn K) are conjugates of hydroxycinnamic acids (HC), including p-coumaric acid, caffeic acid, and ferulic acid, and anthranilate derivatives, including anthranilate, 4-hydroxyanthranilate, and 5-hydroxyanthranilate. Avns are primarily found in oat grain, in which they were originally designated as phytoalexins. Knowledge of the avns biosynthesis pathway has now made it possible to synthesize avns through a genetic engineering strategy, which would help to further elucidate their properties and exploit their beneficial biological activities. The aim of the present study was to synthesize natural avns in Escherichia coli to serve as a valuable resource. We synthesized nine avns in E. coli. We first synthesized avn D from glucose in E. coli harboring tyrosine ammonia lyase (TAL), 4-coumarate:coenzyme A ligase (4CL), anthranilate N-hydroxycinnamoyl/benzoyltransferase (HCBT), and anthranilate synthase (trpEG). A trpD deletion mutant was used to increase the amount of anthranilate in E. coli. After optimizing the incubation temperature and cell density, approximately 317.2 mg/L of avn D was synthesized. Avn E and avn F were then synthesized from avn D, using either E. coli harboring HpaBC and SOMT9 or E. coli harboring HapBC alone, respectively. Avn A and avn G were synthesized by feeding 5-hydroxyanthranilate or 4-hydroxyanthranilate to E. coli harboring TAL, 4CL, and HCBT. Avn B, avn C, avn H, and avn K were synthesized from avn A or avn G, using the same approach employed for the synthesis of avn E and avn F from avn D. Using different HCs, nine avns were synthesized, three of which (avn D, avn E, and avn F) were synthesized from glucose in E. coli. These diverse avns provide a strategy to synthesize both natural and unnatural avns, setting a foundation for exploring the biological activities of diverse avns.

Debrided Skin as a Source of Autologous Stem Cells for Wound Repair

DTIC Science & Technology

2011-08-01

dermal tissue shows the presence of hyalinized collagen (bold arrows) with loss of individual collagen bundles and cellular necrosis . The hypodermal...region consisted of intact adipo- cytes separated by intact interlobular septae and thermally collapsed areas with complete necrosis of both fat cells...and no dsASCs showed predom- inantly acellular multifocal amorphous matrix (Supporting In- formation Fig. S3A, S3B) and was avascular (Supporting Infor

A Randomised Single Centre Study to Compare the Long-term Performance of 4 Designs of the DePuy Ultima LX Stem in Primary Total Hip Replacement

ClinicalTrials.gov

2016-05-09

Osteoarthritis; Post-traumatic Arthritis; Collagen Disorder; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis

A Randomised Multi-centre Study to Compare the Long-term Performance of the Future Hip to 3 Other Implants in Primary Total Hip Replacement

ClinicalTrials.gov

2016-10-06

Osteoarthritis; Post-traumatic Arthritis; Collagen Disorders; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis; Perthes Disease

A Study to Assess the Long-term Performance of SmartSet® HV and SmartSet® GHV Bone Cements in Primary Total Hip Replacement

ClinicalTrials.gov

2017-03-02

Rheumatoid Arthritis; Osteoarthritis; Post-traumatic Arthritis; Collagen Disorders; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis

A Single Centre Study to Assess the Long-term Performance of the Pinnacle™ Cup With a Ceramic-on-ceramic Bearing in Primary Total Hip Replacement

ClinicalTrials.gov

2016-10-06

Rheumatoid Arthritis; Osteoarthritis; Post-traumatic Arthritis; Collagen Disorders; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis

A Multi-centre Study to Assess the Long-term Performance of the Pinnacle™ Cup With a Polyethylene-on-metal Bearing in Primary Total Hip Replacement

ClinicalTrials.gov

2017-06-27

Rheumatoid Arthritis; Osteoarthritis; Post-traumatic Arthritis; Collagen Disorders; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis

A Two Centre Study to Assess the Long-term Performance of the Pinnacle™ Cup With a Metal-on-Metal Bearing in Primary Total Hip Replacement

ClinicalTrials.gov

2016-10-06

Rheumatoid Arthritis; Osteoarthritis; Post-traumatic Arthritis; Collagen Disorders; Avascular Necrosis; Traumatic Femoral Fractures; Nonunion of Femoral Fractures; Congenital Hip Dysplasia; Slipped Capital Femoral Epiphysis

Actis Total Hip System 2 Year Follow-up

ClinicalTrials.gov

2017-08-14

Osteoarthritis; Traumatic Arthritis; Rheumatoid Arthritis; Congenital Hip Dysplasia; Avascular Necrosis of the Femoral Head; Acute Traumatic Fracture of the Femoral Head or Neck; Certain Cases of Ankylosis; Non-union of Femoral Neck Fractures; Certain High Sub-Capital & Femoral Neck Fractures in Elderly

The correlation between Salter's criteria for avascular necrosis of the femoral head and Kalamchi's prognostic classification following the treatment of developmental dysplasia of the hip.

PubMed

Tsukagoshi, Y; Kamegaya, M; Kamada, H; Saisu, T; Morita, M; Kakizaki, J; Tomaru, Y; Yamazaki, M

2017-08-01

The aim of this study was to evaluate the correlation between Salter's criteria and Kalamchi's classification of avascular necrosis in patients treated for developmental dysphasia of the hip (DDH). The study involved a retrospective analysis of 123 patients (123 hips) with DDH treated by operative and non-operative reduction before the age of two years, with a minimum follow-up of ten years. Salter's criteria (S1 to S4) were determined from radiographs obtained at one to two years post-reduction, whilst the Kalamchi grade was determined from radiographs obtained at ten or more years of age. Early post-reduction radiographs were also used to evaluate the centre-head distance discrepancy (CHDD) and the occurrence of a dome-shaped deformity of the proximal femoral metaphysis (D-shaped metaphysis). The prognosis was described as good (Kalamchi grade K0 or KI), fair (Kalamchi grade KII) or poor (Kalamchi grade KIII or KIV) for analysis and correlation with the early Salter criteria, CHDD and D-shaped metaphysis. S1 and S2 criteria were predictive of a poor prognosis. The outcome following S3, S4 and S3 + S4 varied; 18 (40%) had a good prognosis, 17 (38%) a fair prognosis and ten (22%) a poor prognosis. A CHDD ≥ 10% and a D-shaped metaphysis were also predictive of a poor prognosis. The Salter criteria were predictive of the Kalamchi grade of avascular necrosis in patients with DDH aged ten or more years after reduction of the hip. Cite this article: Bone Joint J 2017;99-B:1115-20. ©2017 The British Editorial Society of Bone & Joint Surgery.

Mechanisms of Angiogenesis and Lymphangiogenesis in TSC Skin Tumors

DTIC Science & Technology

2011-09-16

associated macrophage PKD Polycystic kidney disease TGF-β Transforming growth factor-β pS6 Phospho ribosomal protein S6 TNF-α Tumor necrosis factor...blood supply. They are found in the skin and other tissues except the central nervous system, bone marrow and avascular structures including epidermis...273:8413-8418 232. Cha HS, Bae EK, Koh JH, Chai JY, Jeon CH, Ahn KS, Kim J, Koh EM: Tumor necrosis factor-alpha induces vascular endothelial

Angiogenesis Research to Improve Therapies for Vascular Leak Syndromes, Intra-abdominal Adhesions, and Arterial Injuries

DTIC Science & Technology

2008-04-01

small-cell lung cancer; TFP1, transferrin pseudogene 1; TGFβ, transforming growth factor-β; TNF, tumour- necrosis factor; uPA, urokinase-type plasminogen...Cell 79, 315–328 (1994). 23. Frater-Schroder, M., Risau, W., Hallmann, R., Gautschi, P. & Bohlen, P. Tumor necrosis factor type α, a potent inhibitor...relatively thin (skin) or avascular (cartilage) tissues, where post- implantation vascularization from the host is sufficient. To overcome the problem

Traumatic inferior shoulder dislocation: a review of management and outcome.

PubMed

Nambiar, Mithun; Owen, David; Moore, Peter; Carr, Ashley; Thomas, Malcolm

2018-02-01

Traumatic inferior shoulder dislocation (ISD) is rare, estimated to occur in 0.5% of all shoulder dislocations. We describe the demographics, natural history and outcome of this injury. The aim of the study is to provide a summary of the demographics, clinical presentation, management and outcome of patients who suffer ISD METHODS: We conducted a systematic review of the English language literature on ISD using PubMed, Medline, CINHAL, Cochrane Database and Evidence-Based Medicine Reviews. Articles were examined independently by two of the authors and data were extracted using a standard form. Descriptive statistics were performed. 199 patients were identified, from 101 articles. Mean age was 44 years (range 13-94 years). All cases were caused by trauma, with falls accounting for 44% of all cases. There were three reported cases (2%) of open dislocations and 29 cases (15%) of bilateral ISD. Proximal humerus and scapular fractures were reported in 39 and 8% of patients, respectively. Neurological injury after dislocation was noted in 58 patients (29%). Vascular injury was noted in 20 patients (10%), which included axillary arterial injury in 19 patients and an upper limb deep vein thrombosis in one patient. Follow-up data were available for 107 patients (54%), with an average duration of 2.7 years (1 week-32 years). Avascular necrosis (AVN) was noted between 8 weeks and 2 years after initial injury in three patients (1.5%). Clinical and radiographic assessment of ISD is key to diagnosis and successful reduction. Patients can be treated with shoulder immobilisation for 2-3 weeks. In the setting of ongoing pain or instability, further imaging should be performed. The outcome of ISD is generally favourable.

Characterization of opioid use in sickle cell disease.

PubMed

Han, Jin; Zhou, Jifang; Saraf, Santosh L; Gordeuk, Victor R; Calip, Gregory S

2018-05-01

Opioid analgesics are commonly used to treat vaso-occlusive pain episodes in sickle cell disease (SCD), but comprehensive evidence characterizing opioid use in this patient population is limited. Our objective was to characterize opioid use patterns among SCD patients using a large nationwide database. A large, US medical claims database was utilized to identify a cohort of 3882 SCD patients, and characteristics of opioid use were analyzed. Clinical variables including age, gender, medication use, health care utilization, and medical history were evaluated for correlations with opioid use. Forty percent of patients took opioid medications during a 12-month span, and the prevalence of any opioid use was highest for 20 to 29-year-old patients (58%). The median daily opioid dose was 1.85 mg (interquartile range: 0.62-10.68 mg) oral morphine equivalents (OME). While most opioid users took between 0 and 5 mg OME daily, 3% of pediatric patients and 23% of adult patients used more than 30-mg OME daily. High-dose opioid use was associated with older age, hydroxyurea therapy, nonsteroidal anti-inflammatory drug (NSAID) use, and frequent inpatient hospitalizations. In multivariable-adjusted analyses, patients with vaso-occlusive complications such as pain crisis (OR = 3.8, 95% CI 2.7-5.3) and avascular necrosis (AVN) (OR = 3.7, 95% CI 2.7-5.1) were associated with high-dose opioid use. Our study showed that only 40% SCD patients were on opioid analgesics during a 12-month span. However, a non-trivial number of patients used a much higher dose of opioids despite a relatively low average daily opioid dose among SCD patients, particularly with vaso-occlusive complications. Copyright © 2017 John Wiley & Sons, Ltd.

Rheumatic diseases in HIV-infected patients in the post-antiretroviral therapy era: a tertiary care center experience.

PubMed

Parperis, Konstantinos; Abdulqader, Yasir; Myers, Robert; Bhattarai, Bikash; Al-Ani, Muhsen

2018-04-04

The aim of the study was to calculate the proportion of rheumatic diseases in HIV patients who were receiving ART and to identify association of the HIV medications with the development of rheumatologic diseases. We conducted a retrospective chart review during the period of 2010 to 2016. We identified 2996 patients as having chronic HIV infection and on ART, and we collected data regarding patient's demographic characteristics, comorbidities, CD 4 count, HIV viral load, and ART. One hundred thirteen out of 2996 HIV patients (3.8%) were found to have a rheumatic condition (mean age of 48.6 years, 83% male). The most frequent musculoskeletal condition was avascular necrosis (AVN) in 39 (1.3%), and the most frequent autoimmune condition was psoriasis in 28 patients (1%). Compared with the 200 HIV patients without any diagnosis of rheumatic disease were the older patients with rheumatic conditions (mean age of 48.9 vs. 42.7 years; p < 0.01), and had a longer duration of HIV infection (mean duration of 15.5 vs. 10.3 years; p < 0.01). The odds of rheumatic conditions were 1.7 times higher in males (relative to females). Those who received integrase inhibitors were more likely (63.3%) to develop rheumatologic manifestations relative to those who never received integrase inhibitors (21.6%; p < 0.01). The proportion of rheumatic diseases in HIV patients appears to be comparable to the prevalence in the US population. Older age, longer duration of HIV infection, and the use of ART regimens containing integrase inhibitors, appear to increase the risk of developing a rheumatic condition.

Outcomes Study of the TM Reverse Shoulder System Used in Primary or Revision Reverse Total Shoulder Arthroplasty

ClinicalTrials.gov

2018-02-13

Osteoarthritis; Rheumatoid Arthritis; Post-traumatic Arthritis; Ununited Humeral Head Fracture; Irreducible 3-and 4-part Proximal Humeral Fractures; Avascular Necrosis; Gross Rotator Cuff Deficiency; Failed Total Shoulder Arthroplasty (Both Glenoid and Humeral Components Require Revision

Microstructures and properties of cancellous bone of avascular necrosis of femoral heads

NASA Astrophysics Data System (ADS)

Yao, Xuefeng; Wang, Peng; Dai, Ruchun; Yeh, Hsien Yang

2010-03-01

The aim of this study is to investigate microscopic structure and characterize cancellous bone of avascular necrosis of the femoral head (ANFH). The rabbit model of the ANFH is established. The histopathologic features are studied successfully. The differences between the steroid-injection group (S.G.) and the controlled group (C.G.) are examined, including the weight of rabbits, the hematological examination and the three-dimensional structures. It is found that the plasma levels of cholesterol (CHO), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) in S.G. are lower than those in C.G. when the triglyceride (TG) increased in the S.G.; but the bone mineral content (BMC) and the structural model index (SMI) of the organ and tissue decreased significantly in S.G. Three-dimensional structures of the femoral head are obtained using micro-computed tomography (CT) scanning and the mechanical model is established to analyze the influences of these structural changes on the mechanical properties of the cancellous bone.

Avascular Necrosis of the Femoral Head: Are Any Genes Involved?

PubMed Central

Pouya, Farzaneh; Kerachian, Mohammad Amin

2015-01-01

Avascular necrosis of the femoral head (ANFH) is a pathologic process that results from interruption of blood supply to the femur bone resulting in the death of bone cells and collapse of the femoral head. Nontraumatic ANFH continues to be a significant challenge to orthopedic surgeons. While the exact mechanisms remain elusive, many new insights have emerged from research in the last decade that has given us a clearer picture of the pathogenesis of nontraumatic ANFH. Progression to the end stage of ANFH appears to be related to five main mechanisms: hypercoagulable conditions, angiogenesis suppressions, hyperadipogenesis, heritable states, and switching the bone remodelling into bone resorption. Researchers have been examining the pathogenic mechanisms of ANFH but none of these theories have been firmly confirmed although some appear more plausible than the others. All of these factors can switch bone remodelling into bone resorption, which can further lead to ANFH progression ending up to femoral head collapse. PMID:26213697

Extensive Bone Reaction From Catastrophic Oxidized Zirconium Wear.

PubMed

Cassar-Gheiti, Adrian J; Collins, Dennis; McCarthy, Tom

2016-01-01

The use of alternative bearing surfaces for total hip arthroplasty has become popular to minimize wear and increase longevity, especially in young patients. Oxidized zirconium (Oxinium; Smith & Nephew, Memphis, Tennessee) femoral heads were introduced in the past decade for use in total hip arthroplasty. The advantages of oxidized zirconium include less risk of fracture compared with traditional ceramic heads. This case report describes a patient with a history of bilateral avascular necrosis of the femoral head after chemotherapy for acute lymphoblastic leukemia. Nonoperative management of avascular necrosis failed, and the patient was treated with bilateral total hip arthroplasty. The patient was followed at regular intervals and had slow eccentric polyethylene wear during a 10-year period. After 10 years, the patient had accelerated wear, with femoral and acetabular bone changes as a result of Oxinium and ultrahigh-molecular-weight polyethylene wear during a 6-month period. This article highlights the unusual accelerated bone changes that occurred as a result of Oxinium wear particles. Copyright 2016, SLACK Incorporated.

Aspects of postoperative magnetic resonance imaging of patients with avascular necrosis of the femoral head, treated by advanced core decompression.

PubMed

Lazik, Andrea; Landgraeber, Stefan; Claßen, Tim; Kraff, Oliver; Lauenstein, Thomas C; Theysohn, Jens M

2015-10-01

To analyze remodeling processes after advanced core decompression (ACD) in patients with avascular femoral head necrosis by means of 3T MRI and to identify indicators for clinical outcome considering the defect size and characteristics of the bone graft and of the neighboring regeneration tissue. Thirty-four hips, with preexisting preoperative MRIs in 21 cases, were examined 1-34 months (mean 12.7) postoperatively by 3T MRI. The volume of necrosis was measured manually pre- and postoperatively to calculate absolute as well as percentage necrosis reduction. The signal intensity of the bone graft was quantified using a 4-point scale. Border phenomena between the bone graft and bone were described and classified into groups. Wilcoxon sign-rank test was used to identify correlations between the analyzed items and clinical signs of femoral head collapse after a mean follow-up time of 28.6 months (10.4-46.8). Mean percentage reduction of necrosis was significantly higher in asymptomatic patients (59.36%) compared to patients with signs of femoral head collapse (28.78%, p = 0.008). Signal intensity of the bone graft increased in T1w and T2w TIRM sequences over time after surgery and was significantly higher in asymptomatic patients. Five border phenomena between the bone graft and healthy bone were identified. Among them, the so-called "rail sign" representing three layers of remodeling tissue correlated with the histological observations. A variety of border phenomena representing remodeling processes have been described using 3T MRI. Beneath the percentage amount of necrosis reduction, we identified the signal intensity of the bone graft as an indicator for clinical outcome.

Hip fracture surgeries

MedlinePlus

... risks. Risks Following are risks of surgery: Avascular necrosis. This is when the blood supply in part of the femur is cut off for a period of time. This can cause part of the bone to die. Injury to nerves or blood vessels. Parts of the hip bone may not join ...

77 FR 19293 - Orthopaedic and Rehabilitation Devices Panel of the Medical Devices Advisory Committee; Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-30

... as rheumatoid arthritis; c. Correction of functional deformity; and, d. Revision procedures where... the hip (DDH); or b. Inflammatory arthritis such as rheumatoid arthritis. Resurfacing systems are... degenerative joint disease (NIDJD) such as osteoarthritis, avascular necrosis, post-traumatic arthritis...

Fixation of 4-part fractures of the proximal humerus: Can we identify radiological criteria that support locking plates or IM nailing? Comparative, retrospective study of 107 cases.

PubMed

Gadea, F; Favard, L; Boileau, P; Cuny, C; d'Ollone, T; Saragaglia, D; Sirveaux, F

2016-12-01

No objective criteria exist to help surgeons choose between IM nailing and plate fixation for 4-part fractures of the proximal humerus. The goal of this study was to identify radiological criteria that would make one technique a better choice than the other. This was a comparative, multicentre, retrospective study of 54 cases of antegrade nailing and 53 cases of plating performed between 1st January 2009 and 31 December 2011 for 4-part fractures of the proximal humerus. All patients had a minimum radiological and clinical follow-up of 18 months. The functional outcomes were evaluated using the weighted Constant score; a poor result was defined as a weighted Constant score<70%. The following radiological criteria were evaluated during the preoperative assessment and at the last follow-up: initial displacement and reduction of humeral head and tuberosities; morphology of the medial column (i.e. calcar comminution, posteromedial hinge, size of metaphyseal head extension); occurrence of avascular necrosis (AVN). After an average follow-up of 42 months, the weighted Constant scores and rate of poor outcomes were 77% and 48% in the nail group and 81% and 38% in the plate group, respectively (ns). The humeral head was reduced into an anatomical position, valgus or varus in 57%, 30% and 13% of cases in the nail group, and 58%, 29% and 13% in the plate group, respectively. The tuberosities healed in an anatomical position in 72% of nail cases and 70% of plate cases (ns). Only the presence of a medial hinge preoperatively had an effect on the functional outcomes in the nail and plate groups: the weighted Constant scores (P=0.05) and rate of poor outcomes (P=0.02) were 82% and 52% in the nail group and 97% and 9% in the plate group, respectively. The complication rates were comparable: the rates of AVN and articular screw penetration were 17% and 11% in the nail group, and 15% and 11% in the plate group, respectively. The surgical revision rate was 18.5% in the nail group and 30% in the plate group. If the medial hinge is preserved, we recommend locking plate fixation. In other cases, either technique can be used as long as the general rules of internal fixation are applied: reduction of the tuberosities, varus correction and stabilization of the calcar area. IV, retrospective study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The Development of the Ciliary Epithelium in the Embryonic Chicken Eye

DTIC Science & Technology

1989-08-04

aqueous humor, which nourishes the avascular tissues in the anterior segment and generates intraocular pressure (IOP). IOP is the pressure contained...lightly stained. At higher magnification, tissue necrosis is evident in the central region. (60x). j 168 Figure 44. Graph of the labelling index

Case report: AVN of the femoral head five year follow-up of the combination of ipsilateral femoral neck and sub-trochanteric fracture.

PubMed

Zhang, Wei; Zhu, Feng; Dong, Hanqing; Xu, Yaozeng

2016-04-01

To our knowledge, the type of combination of ipsilateral femoral neck and sub-trochanteric fracture is rare. And the long term follow-up is seldom been reported. A 60 year old woman suffered from a traffic accident. We gave her the intramedullary nail treatment for the combination of ipsilateral femoral neck and sub-trochanteric fracture, and the fracture indeed cured after one year and there is no clue of necrosis of the femoral head, but after 5 years, there is an evidence of necrosis of the femoral head. Combination of ipsilateral femoral neck and sub-trochanteric fracture should be kept in mind. Patients with this unusual fracture should be kept under surveillance for longer than might be thought currently to be necessary for there is a possibility of necrosis of the femoral head, even a nondisplaced femoral neck fracture.

Resuscitation from Hypovolemia in Swine with Intraosseous Infusion of a Saturated Salt-Dextran Solution (SSD)

DTIC Science & Technology

1992-10-01

marrow and the proximal tibia is often used for emergency vascular access (3-5). In adults, however, avascular yellow marrow replaces the red marrow of...for histological evaluation of acute lesions, presence or absence of thrombi, fat or bone emboli, necrosis or hemorrhage to the lung, and decreased

Alterations of sympathetic nerve fibers in avascular necrosis of femoral head.

PubMed

Li, Deqiang; Liu, Peilai; Zhang, Yuankai; Li, Ming

2015-01-01

Avascular necrosis of the femoral head (ANFH) was mainly due to alterations of bone vascularity. And noradrenaline (NA), as the neurotransmitter of the sympathetic nervous system (SNS), leads to the vasoconstriction by activating its α-Receptor. This study was to explore the nerve fiber density of the femoral head in the rabbit model of ANFH. Twenty New Zealand white rabbits were used in this study. The rabbit model of ANFH was established by the injection of methylprednisolone acetate. The nerve fiber density and distribution in the femoral head was determined using an Olympus BH2 microscope. Significant fewer sympathetic nerve fibers was found in the ANFH intertrochanteric bone samples (P = 0.036) with osteonecrosis. The number of sympathetic nerve fibers was compared between the two groups. And less sympathetic nerve fibers were found in later stage ANFH samples in comparison with those of early stages. ANFH might be preceded by an inflammatory reaction, and an inflammatory response might lead to arthritic changes in tissue samples, which in turn reduces the number of sympathetic nerve fibers.

Modelling the formation of necrotic regions in avascular tumours.

PubMed

Tindall, M J; Please, C P; Peddie, M J

2008-01-01

The mechanisms underlying the formation of necrotic regions within avascular tumours are not well understood. In this paper, we examine the relative roles of nutrient deprivation and of cell death, from both the proliferating phase of the cell cycle via apoptosis and from the quiescent phase via necrosis, in changing the structure within multicellular tumour spheroids and particularly the accumulation of dead cell material in the centre. A mathematical model is presented and studied that accounts for nutrient diffusion, changes in cell cycling rates, the two different routes to cell death as well as active motion of cells and passive motion of the dead cell material. In studying the accumulation of dead cell matter we do not distinguish between the route by which each was formed. The resulting mathematical model is examined for a number of scenarios. Results show that in many cases the size of the necrotic core is closely correlated with low levels in nutrient concentration. However, in certain cases, particularly where the rate of necrosis is large, the resulting necrotic core can lead to regions of non-negligible nutrient concentration-dependent upon the mode of cell death.

Talar injuries--the orthopaedic challenge.

PubMed

Lesić, Aleksandar R; Zagorac, Slavisa G; Bumbasirević, Marko Z

2012-01-01

Injuries of the talus represents an important part of the foot and ankle trauma. Since talar bone connect the lower limb and foot, the sequelas of its trauma could have significant influence on the function of the whole lower limb and gait. The specific vascularization of the talus results in delayed union and even in the avascular necrosis. The diagnosis of the fractures of the talus can be made on the x-rays, but sometimes real picture of the fracture pattern can be seen only in the CT scans. Ocult fractures such as osteochondral fractures and avascular necrosis can be exactly detected on MRI in aim not to be overlookded as the ankle sprain diagnosis. The precise reduction and stable internal fixation is mandatory in the treatment to enable the anatomical position of the talonavicular, talocrural and subtalar joint and to make possible early motion and rehabilitation, without weight bearing. On the other hand, crushed fractures, open fractures and the Hawkins III-IV fractures with the dislocations of the talar body sometimes needs salvage procedures like Blair or tibio-talar or tibio-calcaneal fusion.

[Mechanism of "crescent sign" formation in avascular necrosis of femoral head].

PubMed

Zhang, Nianfei; Qi, Shengwen; Chai, Jianfeng

2008-03-01

To investigate corresponding relation between structure change of the femoral head with "crescent sign" and stress exerted on the avascular necrosis of femoral head, to explore the mechanism of the "crescent sign" formation. From March 1998 to April 2003, the femoral heads of 18 hips in 16 cases having osteonecrosis and "crescent sign" in X-ray film before total hip arthroplasty, were collected. General and coronal section plane morphology of the femoral heads were observed. The principle of effective stress and stress concentration theory were used to explain the phenomena and structure changes in osteonecrosis of the femoral head. Cancellous bone existed as a three-dimensional, interconnected network of trabeculae rods and plates, with 50%-90% of porosity and 20-30 mmHg bone marrow pressure. According to the definition of porous media, bones especially cancellous bone was a kind of solid and liquid two phases porous media. Cross-sectional structure changes in the junction between subchondral plate and cancellous were the place where stress concentrated. The principle of effective stress and stress concentration theory could explain the phenomena and their relationship that occurred in avascular necrosis of the femoral head. The "crescent sign" starts in an area of very focal resorption in the subchondral plate laterally and peripherally. The focal resorption in the subchondral plate breaks the continuity of subchondral plate and causes stress concentration in the resorption region. The concentrated stress accumulates in the junction between subchondral plate and unrepaired necrotic cancellous bone brings on the fracture right below the subchondral plate. The focal resorption of the subchondral plate also provides a pathway for the pore water in the unrepaired necrotic bone skeleton to outflow, therefore cause effective stress increase and unrepaired necrotic bone skeleton be compacted by increased effective stress applied on unrepaired necrotic cancellous bone skeleton, and results in the volume decrease of unrepaired necrotic cancellous bone and the formation of cavum below the subchondral plate. The cavum shows "crescent sign" in the X-ray film.

Quantification of Femoral Neck Exposure Through a Minimally Invasive Smith-Petersen Approach

DTIC Science & Technology

2010-06-01

Gautier E, et al. Surgical dislocation of the adult hip: A technique with full access to femoral head and acetabulum without the risk of avascular ... necrosis . J Bone Joint Surg (Br). 2001;83:1119 1124. 24. Gautier E, Ganz K, Krugel N, et al. Anatomy of the medial femoral circumflex artery and its

Does vasculitis alone cause AVN? A review of literature.

PubMed

Abraham, Rtika R; Meyerhoff, John O

2013-10-01

AVN is caused by a disease, or severe trauma that affects the blood supply to the bone or in many cases may be idiopathic, with no known cause. AVN pathophysiology is most closely linked to SLE literature, and there is a strong cause and effect relationship between corticosteroid intake and AVN development in SLE patients, and AVN is extremely rare in the absence of steroid use. Apart from few anecdotal reports, there is no data on exact pathophysiologic mechanisms responsible for AVN in the setting of vasculitis. We saw a 69-year-old man with femoral AVN and a possibility of vasculitis as the underlying cause was raised by the radiologist, and hence we present this literature search on vasculitis per se causing AVN of the bone.

Inhibition of Nitric Oxide Synthase Through Depletion of Its Cofactor Tetrahydrobiopterin as a Novel Strategy for Breast Cancer Anti-Angiogenic Therapy

DTIC Science & Technology

2004-09-01

was observed in treated tumors with many becoming completely avascular . A representative image of the effect of MnTE-2-PyP5+ on decreasing vascular...inhibiting downstream expression of important factors such as tumor necrosis factor and interleukin- 1 3 (31, 32). Relevant to the current study

Evaluation of the stability of reference genes in bone mesenchymal stem cells from patients with avascular necrosis of the femoral head.

PubMed

Wang, X N; Yang, Q W; Du, Z W; Yu, T; Qin, Y G; Song, Y; Xu, M; Wang, J C

2016-05-25

This study aimed to evaluate 12 genes (18S, GAPDH, B2M, ACTB, ALAS1, GUSB, HPRT1, PBGD, PPIA, PUM1, RPL29, and TBP) for their reliability and stability as reference sequences for real-time quantitative PCR (RT-qPCR) in bone marrow-derived mesenchymal stem cells (BMSCs) isolated from patients with avascular necrosis of the femoral head (ANFH). BMSCs were isolated from 20 ANFH patients divided into four groups according to etiology, and four donors with femoral neck fractures. Total RNA was isolated from BMSCs and reverse transcribed into complementary DNA, which served as a template for RT-qPCR. Three commonly used programs were then used to analyze the results. Reference gene expression varied within each group, between specific groups, and among all five groups. Based on comparisons of all five groups, two of the programs used suggested that HPRT1 was the most stable reference gene, while 18S and ACTB were the most variable. Among the 12 candidate reference genes, HPRT1 exhibited the greatest reliability, followed by PPIA. Thus, these sequences could be used as references for the normalization of RT-qPCR results.

[Pathological changes of the blood vessels in rabbit femoral head with glucocorticoid-induced necrosis].

PubMed

Hu, Zhi-ming; Wang, Hai-bin; Zhou, Ming-qian; Yao, Xin-sheng; Ma, Li; Wang, Xiao-ning

2006-06-01

To observe the pathological changes in the blood vessels in rabbit femoral head with glucocorticoid-induced necrosis and investigate the pathogenesis of glucocorticoid-induced osteonecrosis. Twenty New Zealand white rabbits were randomly divided into two groups, namely group A. which was injected with horse serum and prednisone and group B as the control group. Chinese ink was injected into the femoral cavity of the rabbits to observe the blood vessels in the femoral head under optical microscope and the femoral head was examined histopathologically. Compared with the normal control group, the rabbits in group A had significantly decreased number of perfused vessels, which was featured by defective perfusion, osteocytie pyknosis or necrosis, increase of empty ostoocyte lacunae and fat cells, decrease of hematopoietic tissue, and blood vessel occlusion. Vascular occlusion and vasculitis due to glucocorticoid treatment may cause avascular necrosis of the femoral head.

[Austin's horizontal V-shaped sliding osteotomy of the metatarsal head [Chevron-osteotomy) in the treatment of hallux valgus].

PubMed

Steinböck, G

1996-08-01

From 1983 to 1995, 1587 patients suffering from hallux abductovalgus were treated with the Austin bunionectomy. The operation consists of a medial exostosis removal, a V-shaped laterally directed displacement osteotomy of the metatarsal head, lateral release and medial reefing of the capsulo-ligamentous structures. Lateral transposition is facilitated by performing a sufficient lateral release consisting of dissection of the lateral metatarsophalangeal ligament and separation of the adductor tendon from the base of the phalanx and the lateral sesamoid. In the case of intermetatarsal angles greater than 15 degrees, the metatarsal-sesamoid ligament is also severed just above the lateral sesamoid. The periosteum is stripped in a limited fashion dorsally and toward the plantar, leaving its insertion at the metatarsal head intact. After this procedure, reposition of the metatarsal head onto the sesamoids is usually possible and is maintained by reconstruction of the medial metatarsal-sesamoid ligament. In the author's own research material, metatarsophalangeal angles larger than 50 degrees and intermetatarsal angles of over 20 degrees could be corrected. Pronation of the toe is usually corrected by tenotomy of the abductor tendon near the base of the phalanx. Avascular necrosis is extremely rare with a careful operative technique. In our extensive research material, four cases of AVN were recognized. Provided there is free motion of the joint (60-0-20), mild radiological signs of osteoarthritis are no contraindication for the operation. Even in the aged, good results can be achieved provided there are no trophic problems. The Austin bunionectomy has proved to be a versatile method for treating bunion problems. The possibility of transposing the metatarsal head laterally, toward the plantar, proximally and distally by altering the direction of the osteotomy, as well as tilting it medially or laterally, has made this osteotomy an invaluable tool for addressing various problems in bunion surgery.

Inhibition of sarcoplasmic reticulum Ca(2+)-ATPase decreases atrioventricular node-paced heart rate in rabbits.

PubMed

Cheng, Hongwei; Smith, Godfrey L; Orchard, Clive H; Hancox, Jules C; Burton, Francis L

2012-10-01

Recent data indicate that Ca(2+) cycling in isolated atrioventricular node (AVN) cells contributes to setting spontaneous rate. The aim of the present study was to extend this observation to the intact AVN in situ, by evaluating the effects of inhibiting sarcoplasmic reticulum Ca(2+) uptake with cyclopiazonic acid (CPA) on intact AVN spontaneous activity and its response to isoprenaline. A model of the AVN-paced heart was produced to investigate intact AVN automaticity, by surgical ablation of the sino-atrial node (SAN) in the rabbit Langendorff-perfused heart. Electrograms were recorded from a site close to the AVN (triangle of Koch), an atrial site above the AVN, the left atrium and right ventricle, enabling AVN pacing of the preparation to be confirmed. Before SAN ablation, the heart rate was 166.8 ± 5.4 beats min(-1). Ablation of the SAN was clearly indicated by a sudden and significant decrease of heart rate to 108.6 ± 9.6 beats min(-1) (P < 0.01, n = 10). Isoprenaline (100 nm) increased AVN rate to 187.8 ± 12.0 beats min(-1) after 1 min of application (P < 0.01, n = 10). Cyclopiazonic acid (10 and 30 μm) decreased AVN rate to 81.6 ± 4.8 (n = 9) and 77.4 ± 6.0 beats min(-1) (n = 7), respectively [P < 0.05, 10 or 30 μm CPA versus control (n = 10)] and also reduced the AVN rate increase in response to isoprenaline from 78.8 ± 10.0 to 46.8 ± 6.8 and 26.7 ± 5.3%, respectively (P < 0.01). These inhibitory effects of CPA on the intact AVN rate and its response to isoprenaline indicate that Ca(2+) cycling is important to the intact AVN spontaneous activity and its acceleration during sympathetic stimulation.

The BLSTs Role in the Materiel Enterprise

DTIC Science & Technology

2016-05-17

CECOM AVN LAR AMCOM LAR PM UAS CECOM AVN LAR AMCOM LAR PM UAS CECOM AVN LAR PM UAS Ba gr am Sh an k M ar m al Ja la la ba d Legend Coordinating...relationship Administrative control AED = Aviation Engineering Directorate AMCOM = Aviation and Missile Command AVN = Avionics BLST = Brigade logistics

Computer Three-Dimensional Reconstruction of the Atrioventricular Node

PubMed Central

Li, Jue; Greener, Ian D.; Inada, Shin; Nikolski, Vladimir P.; Yamamoto, Mitsuru; Hancox, Jules C.; Zhang, Henggui; Billeter, Rudi; Efimov, Igor R.; Dobrzynski, Halina; Boyett, Mark R.

2009-01-01

Because of its complexity, the atrioventricular node (AVN), remains 1 of the least understood regions of the heart. The aim of the study was to construct a detailed anatomic model of the AVN and relate it to AVN function. The electric activity of a rabbit AVN preparation was imaged using voltage-dependent dye. The preparation was then fixed and sectioned. Sixty-five sections at 60- to 340-μm intervals were stained for histology and immunolabeled for neurofilament (marker of nodal tissue) and connexin43 (gap junction protein). This revealed multiple structures within and around the AVN, including transitional tissue, inferior nodal extension, penetrating bundle, His bundle, atrial and ventricular muscle, central fibrous body, tendon of Todaro, and valves. A 3D anatomically detailed mathematical model (≈13 million element array) of the AVN and surrounding atrium and ventricle, incorporating all cell types, was constructed. Comparison of the model with electric activity recorded in experiments suggests that the inferior nodal extension forms the slow pathway, whereas the transitional tissue forms the fast pathway into the AVN. In addition, it suggests the pacemaker activity of the atrioventricular junction originates in the inferior nodal extension. Computer simulation of the propagation of the action potential through the anatomic model shows how, because of the complex structure of the AVN, reentry (slow-fast and fast-slow) can occur. In summary, a mathematical model of the anatomy of the AVN has been generated that allows AVN conduction to be explored. PMID:18309098

Therapeutic effects of selective atrioventricular node vagal stimulation in atrial fibrillation and heart failure.

PubMed

Zhang, Youhua; Popović, Zoran B; Kusunose, Kenya; Mazgalev, Todor N

2013-01-01

Atrial fibrillation (AF) and heart failure (HF) frequently coexist. We have previously demonstrated that selective atrioventricular node (AVN) vagal stimulation (AVN-VS) can be used to control ventricular rate during AF. Due to withdrawal of vagal activity in HF, the therapeutic effects of AVN-VS may be compromised in the combined condition of AF and HF. Accordingly, this study was designed to evaluate the therapeutic effects of AVN-VS to control ventricular rate in AF and HF. A combined model of AF and HF was created by implanting a dual chamber pacemaker in 24 dogs. A newly designed bipolar electrode was inserted into the ganglionic AVN fat pad and connected to a nerve stimulator for delivering AVN-VS. In all dogs, HF was induced by high rate ventricular pacing at 220 bpm for 4 weeks. AF was then induced and maintained by rapid atrial pacing at 600 bpm after discontinuation of ventricular pacing. These HF + AF dogs were randomized into control (n = 9) and AVN-VS (n = 15) groups. In the latter group, vagal stimulation (310 μs, 20 Hz, 3-7 mA) was delivered continuously for 6 months. Compared with the control, AVN-VS had a consistent effect on ventricular rate slowing (by >50 bpm, all P < 0.001) during the entire 6-month observation period that was associated with left ventricular functional improvement. Moreover, AVN-VS was well tolerated by the treated animals. AVN-VS achieved consistent rate slowing, which was associated with improved ventricular function in a canine AF and HF model. Thus, AVN-VS may be a novel, effective therapeutic option in the combined condition of AF and HF. © 2012 Wiley Periodicals, Inc.

An atlas of radiological interpretation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calder, J.F.; Chessell, G.

1988-01-01

This book is concerned with pathologic entities and their impact on the skeleton. The book is divided into nine chapters. After a discussion of normal anatomic features, the authors discuss trauma, avascular necrosis and osteochondritis, bone infections, diseases of the joints, bone tumors, reticuloses and hemopoietic disorders, endocrine and metabolic bone diseases, and congenital abnormalities. A line drawing accompanies every radiograph to contrast the pathologic findings with the normal anatomic features.

Risk of refracture through unicameral bone cysts of the proximal femur.

PubMed

Norman-Taylor, Fabian H; Hashemi-Nejad, Aresh; Gillingham, Bruce L; Stevens, David; Cole, William G

2002-01-01

The authors determined the results after traction or traction and hip spica treatment of the initial fractures through unicameral bone cysts of the proximal femur in 20 children. All of the eight displaced fractures healed, but with coxa vara and avascular necrosis in one, coxa vara in a second, and coxa breva in a third. Spontaneous healing of the cyst occurred in three of the eight children; satisfactory healing was achieved and maintained after intralesional corticosteroid injections in four of the eight children. In the remaining child with a displaced fracture, reactivation of the cyst and exercise-related pain, indicative of an incipient refracture, occurred 3 years after initial presentation. All of the 12 undisplaced fractures healed without deformity or avascular necrosis. Intralesional corticosteroids were used in all of the 12 children because none of them showed spontaneous healing of their cysts. Satisfactory radiographic healing was achieved 1 year after presentation in all of the 12 children. However, one or more refractures resulting from reactivation of the cyst occurred in 6 of the 12 children 2 to 5 years after initial presentation. The results of this study indicate that satisfactory radiographic healing needs to be achieved by the end of the first year and needs to be maintained thereafter to prevent refractures.

[Experimental study on avascular necrosis of femoral head in chickens induced by different glucocorticoides].

PubMed

Xiao, Chun-Sheng; Lin, Na; Lin, Shi-Fu; Wan, Rong; Chen, Wei-Heng

2010-03-01

To study the effects of Methylprednisolone and Dexamethasone on the avascular necrosis of femoral head in chickens. Thirty-six chickens were randomly divided into 6 groups (n = 6): control group (group A), Methylprednisolone low dose group (group B), Methylprednisolone large dose group (group C), small dose Dexamethasone and horse serum group (group D), middle dose Dexamethasone and horse serum group (group E), and Dexamethasone large dose group (group F). On the 6th and 12th weeks, blood samples were obtained to determine the level of total cholesterol triglyeride (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL). On the 12th week, femoral heads were taken off. Paraffin tissue sections were prepared to detect histopathologic change with hematoxylin and eosin staining. On the 6th week, compared with group A, the level of CHO increased significantly in group C and group F (P < 0.05), and TG increased in group B, C and group E, while HDL decreased in group B, C and group E. On the 12th week, the level of TG and CHO increased in group B, C, E and group F, and HDL decreased in group C, D and group E (P < 0.05). LDL was not detected in most chickens. The ratio of empty lacuna was higher in group C and group E compared with those of the control group (P < 0.05). Methylprednisolone is easier to induce osteonecrosis of femoral head than Dexamethasone. The condition of metabolic disorder in blood may be the basic pathomechanism of steroid-induced necrosis of femoral head.

[S3 guideline. Part 2: Non-Traumatic Avascular Femoral Head Necrosis in Adults - Untreated Course and Conservative Treatment].

PubMed

Roth, A; Beckmann, J; Smolenski, U; Fischer, A; Jäger, M; Tingart, M; Rader, C; Peters, K M; Reppenhagen, S; Nöth, U; Heiss, C; Maus, U

2015-10-01

In Germany there are 5000 to 7000 new cases of atraumatic avascular necrosis of the femoral head in adults per year. It occurs mostly in middle age. An increased frequency of idiopathic cases can be observed. Chemotherapy, corticoids and kidney transplants are frequently associated with the disease. In most cases the disease occurs on both sides. Early diagnosis is of particular importance, since in early stages it is most likely to avoid late damage with joint destruction. Whereas previously the temporary operational joint preservation and subsequent joint replacement were often the only option of treatment, conservative and joint-preserving measures today play an increasing role. After the AWMF guidelines for S3 guideline clinical questions were formulated. Over the period from 01/01/1970 to 31/05/2013 a literature search was conducted. Systematic reviews, metaanalyses, original papers and clinical trials of all designs were evaluated. There were a total of 3715 references, of which 422 for the assessment regarding SIGN were eligible and finally 180 were in accord with the defined inclusion and exclusion criteria. For the untreated course and the assessment of conservative measures, a total of 42 references was suitable. In formulating the recommendations the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system was used, which distinguishes A "shall", B "should" and 0 "can". If left untreated, the aFKN within 2 years leads to a subchondral fracture and subsequent collapse. After the diagnosis of femoral head necrosis, the risk of a disease of the opposite side is high within the next 2 years, then unlikely. The sole conservative treatment brings no benefit for the treatment of atraumatic avascular necrosis in the adult. Although it improves function, less pain can be obtained, and surgical intervention can be delayed, the progression is not stopped. Conservative treatment must therefore always be part of the overall treatment. In ARCO stage I to II Iloprost may be considered as a pharmacological approach to reduce the pain and the bone marrow oedema. This also applies to alendronate. Since this is an off-label use, and thus a therapeutic trial, an appropriate patient education must take place. For the use of anticoagulants and statins, there is no recommendation. Also the hyperbaric oxygen therapy, shock waves and pulsating electromagnetic fields or electrical stimulation cannot be recommended. Georg Thieme Verlag KG Stuttgart · New York.

A complete characterization of all-versus-nothing arguments for stabilizer states.

PubMed

Abramsky, Samson; Barbosa, Rui Soares; Carù, Giovanni; Perdrix, Simon

2017-11-13

An important class of contextuality arguments in quantum foundations are the all-versus-nothing (AvN) proofs, generalizing a construction originally due to Mermin. We present a general formulation of AvN arguments and a complete characterization of all such arguments that arise from stabilizer states. We show that every AvN argument for an n -qubit stabilizer state can be reduced to an AvN proof for a three-qubit state that is local Clifford-equivalent to the tripartite Greenberger-Horne-Zeilinger state. This is achieved through a combinatorial characterization of AvN arguments, the AvN triple theorem, whose proof makes use of the theory of graph states. This result enables the development of a computational method to generate all the AvN arguments in [Formula: see text] on n -qubit stabilizer states. We also present new insights into the stabilizer formalism and its connections with logic.This article is part of the themed issue 'Second quantum revolution: foundational questions'. © 2017 The Author(s).

Report to Congress on Sustainable Ranges, 2012

DTIC Science & Technology

2012-05-01

4ID AVN BDE HQ, 41st Fires BDE, 4th Sustainment BDE, 7-158 AVN (-), 6-52 AVN (-), 11th MP BN, 308th MI BDE, 21st Cavalry BDE (Air Combat), TF Odin, 1st...Army Division West HQ, 120 Infantry BDE, 166th AVN , 479 FA BDE, 407 AFSB, 901 SPT BN, 15th Sustainment BDE, 36th EN BDE, 89th MP BDE, 57th SIG BDE...1st Maneuver Enhancement Brigade; 162nd Infantry Training Brigade; the JRTC Operations Group; the 115th CSH and the 5th AVN BN. Home station unit

Anatomy of Atrioventricular Node Artery and Pattern of Dominancy in Normal Coronary Subject: A Comparison between Individuals with and without Isolated Right Bundle Branch Block

PubMed Central

Kazemisaeid, Ali; Pakbaz, Marziyeh; Yaminisharif, Ahmad; Davoodi, Gholamreza; Lotfi Tokaldany, Masoumeh; Hakki Kazazi, Elham

2012-01-01

Background: Isolated right bundle branch block (RBBB) is a common finding in the general population. The atrioventricular node (AVN) artery contributes to the blood supply of the right bundle branch. Our hypothesis was that the anatomy of the AVN artery and the pattern of dominancy differ between subjects with and without RBBB. Methods: We retrospectively studied the coronary angiography of 92 patients with RBBB and 184 age- and gender-matched controls without RBBB. All the subjects had angiographically proven normal coronary arteries. The dominant circulation and precise origin of the AVN artery were determined in each subject. Obtained data were compared between the two study groups. Results: There was no significant difference between the two groups in terms of dominancy (p value = 0.200). Origination of the AVN artery from the right circulatory system was more common in both groups, but this pattern was more prevalent in the cases than in the controls (p value = 0.021). There was a great variation of the AVN artery origin. In the total study population, the AVN artery was more commonly separated from a non crux origin than from the crux area. The prevalence of the non-crux origination of the AVN artery was significantly higher in the cases than in the controls (p value < 0.001). While the origination of the AVN artery from the right circulatory system was more common in both groups, the prevalence of the right origin of the AVN artery was significantly higher in the cases than in the controls. We observed that the AVN artery most commonly originated from the dominant artery but not necessarily from the crux. Conclusion: The anatomy of the AVN artery but not the pattern of dominancy is somewhat different in subjects with RBBB compared with normal individuals. PMID:23323077

The effect of atrial pacing site on electrophysiological properties of the atrioventricular junction and induction of atrioventricular nodal reentry in patients with typical atrioventricular nodal reentrant tachycardia.

PubMed

Kiedrowicz, Radosław M; Kaźmierczak, Jarosław; Wielusiński, Maciej

2017-01-01

Clinical studies in humans have shown the site of atrial stimulation to influence atrioventricular (AV) conduction times and refractory periods, the demonstration of dual AV nodal (AVN) pathways, and induction of AVN reentry. These studies often found conflicting results. Moreover, among enrolled patients a minority of them were found to have AVN reentrant tachycardia (AVNRT). The purpose of this study was to investigate the effect of right and left atrial pacing on the electrophysiological properties of the AV junction in the typical AVNRT population. Ninety-two consecutive patients with typical AVNRT were included. Atrial pacing was performed from the high right atrium (HRA) and the left atrium via the proximal coronary sinus (CS). Stimulation from either the HRA or the CS could result in dual AVN physiology and AVNRT. No site-dependent differences in the ease of induction of dual AVN pathways with variability of initiation from either site were found. However, AVNRT was easier to induce from the HRA. With CS pacing the leftward but not the rightward AVN approaches were the entry point to the AV node because of significantly shorter AH conduction times compared to HRA pacing. Conduction over the leftward AVN extensions could initiate the tachycardia with significantly shorter critical AH interval compared to conduction over the rightward AVN extensions; however, the AH interval during AVNRT and its cycle length were not significantly different. Rightward and leftward AVN extensions are regular features of the AV node. Their different electrophysiological properties lead to variation in the demonstration of discontinuous AVN conduction and AVNRT during right and left atrial pacing. Despite the observation that the left AVN extensions could compose the entry point to the reentrant circuit, there is no evidence that they constitute the critical component of sustained typical AVNRT.

Atrioventricular node functional remodeling induced by atrial fibrillation.

PubMed

Zhang, Youhua; Mazgalev, Todor N

2012-09-01

The atrioventricular node (AVN) plays a vital role in determining the ventricular rate during atrial fibrillation (AF). AF results in profound electrophysiological and structural remodeling in the atria as well as the sinus node. However, it is unknown whether AVN undergoes remodeling during AF. To determine whether AVN undergoes functional remodeling during AF. AVN conduction properties were studied in vitro in 9 rabbits with AF and 10 normal controls. A previously validated index of AVN dual-pathway electrophysiology, His-electrogram alternans, was used to monitor fast-pathway or slow-pathway (SP) AVN conduction in these experiments. AVN conduction properties were further studied in vivo in 7 dogs with chronic AF and 8 controls. Compared with the control rabbits, the rabbits with AF had a longer AVN conduction time (83 ± 16 ms vs 68 ± 7 ms; P <.01), longer AVN effective refractory period (141 ± 27 ms vs 100 ± 9 ms; P <.01), an earlier transition from fast-pathway to SP conduction (at a longer prematurity, 249 ± 60 ms vs 171 ± 24 ms; P <.01), and a slower ventricular rate during simulated AF (RR interval 249 ± 42 ms vs 202 ± 12 ms; P <.01). Notably, a larger proportion of conducted beats utilized the SP in AF preparations (92% ± 12% vs 63% ± 32%; P <.05). Long-term AF in dogs resulted in a longer atrioventricular conduction time and AVN effective refractory period and a slower ventricular rate during AF compared with the controls. Pronounced AVN functional electrophysiological remodeling occurs after long-term AF, which could lead to a spontaneous slowing of the ventricular rate. Furthermore, the SP dominance during AF underscores the effectiveness of its modification by ablation for ventricular rate control during AF. Copyright © 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Anatomy of Atrioventricular Node Artery and Pattern of Dominancy in Normal Coronary Subject: A Comparison between Individuals with and without Isolated Right Bundle Branch Block.

PubMed

Kazemisaeid, Ali; Pakbaz, Marziyeh; Yaminisharif, Ahmad; Davoodi, Gholamreza; Lotfi Tokaldany, Masoumeh; Hakki Kazazi, Elham

2012-11-01

Isolated right bundle branch block (RBBB) is a common finding in the general population. The atrioventricular node (AVN) artery contributes to the blood supply of the right bundle branch. Our hypothesis was that the anatomy of the AVN artery and the pattern of dominancy differ between subjects with and without RBBB. We retrospectively studied the coronary angiography of 92 patients with RBBB and 184 age- and gender-matched controls without RBBB. All the subjects had angiographically proven normal coronary arteries. The dominant circulation and precise origin of the AVN artery were determined in each subject. Obtained data were compared between the two study groups. There was no significant difference between the two groups in terms of dominancy (p value = 0.200). Origination of the AVN artery from the right circulatory system was more common in both groups, but this pattern was more prevalent in the cases than in the controls (p value = 0.021). There was a great variation of the AVN artery origin. In the total study population, the AVN artery was more commonly separated from a non crux origin than from the crux area. The prevalence of the non-crux origination of the AVN artery was significantly higher in the cases than in the controls (p value < 0.001). While the origination of the AVN artery from the right circulatory system was more common in both groups, the prevalence of the right origin of the AVN artery was significantly higher in the cases than in the controls. We observed that the AVN artery most commonly originated from the dominant artery but not necessarily from the crux. The anatomy of the AVN artery but not the pattern of dominancy is somewhat different in subjects with RBBB compared with normal individuals.

Zeitlicher Verlauf der avaskulären Nekrose des Hüftkopfes bei Patienten mit Pemphigus vulgaris.

PubMed

Balighi, Kamran; Daneshpazhooh, Maryam; Aghazadeh, Nessa; Saeidi, Vahide; Shahpouri, Farzam; Hejazi, Pardis; Chams-Davatchi, Cheyda

2016-10-01

Pemphigus vulgaris (PV) wird in der Regel mit systemischen Corticosteroiden und Immunsuppressiva behandelt. Avaskuläre Nekrose (AVN) des Hüftkopfes ist eine gut bekannte schwerere Komplikation einer Corticosteroid-Therapie. Die Charakteristika dieser schweren Komplikation bei PV sind nach wie vor unbekannt. Nicht kontrollierte, retrospektive Untersuchung aller PV-bedingten AVN-Fälle, die in einer iranischen Klinik für bullöse Autoimmunerkrankungen zwischen 1985 und 2013 diagnostiziert wurden. Anhand der Krankenakten von 2321 untersuchten PV-Patienten wurden 45 Fälle (1,93 %) von femoraler AVN identifiziert. Dreißig davon waren Männer. Das mittlere Alter bei der Diagnose der AVN betrug 47,4 ± 14,2 Jahre. Der mittlere Zeitraum zwischen der Diagnose des PV und dem Einsetzen der AVN lag bei 25,3 ± 18,3 Monaten. Mit Ausnahme von acht Fällen (17,8 %) setzte die AVN bei der Mehrheit der Patienten innerhalb von drei Jahren nach Diagnose des PV ein. Die mittlere kumulative Dosis von Prednisolon bei Patienten mit AVN betrug 13.115,8 ± 7041,1 mg. Zwischen der Prednisolon-Gesamtdosis und dem Zeitraum bis zum Einsetzen der AVN bestand eine starke Korrelation (p = 0,001). Bei Patienten mit Alendronateinnahme in der Vorgeschichte war dieser Zeitraum signifikant kürzer (p = 0,01). Die AVN ist eine schwere Komplikation einer Corticosteroid-Behandlung bei Patienten mit PV. Sie wird bei 2 % der Patienten beobachtet und tritt vor allem in den ersten drei Behandlungsjahren auf. Bei Patienten, die höhere Dosen von Prednisolon erhalten, setzt die AVN tendenziell früher ein. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Impact of Tricuspid Regurgitation on the Success of Atrioventricular Node Ablation for Rate Control in Patients With Atrial Fibrillation: The Node Blast Study.

PubMed

Reddy, Yeruva Madhu; Gunda, Sampath; Vallakati, Ajay; Kanmanthareddy, Arun; Pillarisetti, Jayasree; Atkins, Donita; Bommana, Sudharani; Emert, Martin P; Pimentel, Rhea; Dendi, Raghuveer; Berenbom, Loren D; Lakkireddy, Dhanunjaya

2015-09-15

Atrioventricular node (AVN) ablation is an effective treatment for symptomatic patients with atrial arrhythmias who are refractory to rhythm and rate control strategies where optimal ventricular rate control is desired. There are limited data on the predictors of failure of AVN ablation. Our objective was to identify the predictors of failure of AVN ablation. This is an observational single-center study of consecutive patients who underwent AVN ablation in a large academic center. Baseline characteristics, procedural variables, and outcomes of AVN ablation were collected. AVN "ablation failure" was defined as resumption of AVN conduction resulting in recurrence of either rapid ventricular response or suboptimal biventricular pacing. A total of 247 patients drug refractory AF who underwent AVN ablation at our center with a mean age of 71 ± 12 years with 46% being males were included. Ablation failure was seen in 11 (4.5%) patients. There were no statistical differences between patients with "ablation failure" versus "ablation success" in any of the baseline clinical variables. Patients with moderate-to-severe tricuspid regurgitation (TR) were much more likely to have ablation failure than those with ablation success (8 [73%] vs 65 [27%]; p = 0.003). All 11 patients with ablation failure had a successful redo procedure, 9 with right and 2 with the left sided approach. On multivariate analysis, presence of moderate-to-severe TR was found to be the only predictor of failure of AVN ablation (odds ratio 9.1, confidence interval 1.99 to 42.22, p = 0.004). In conclusion, moderate-to-severe TR is a strong and independent predictor of failure of AVN ablation. Copyright © 2015 Elsevier Inc. All rights reserved.

The Diagnosis, Management and Complications Associated with Fractures of the Talus

PubMed Central

J.R, Barnett; MA, Ahmad; W, Khan; A., O’ Gorman

2017-01-01

Fractures of the talus are uncommon injuries that can have devastating consequences. The blood supply to the talus is tenuous and injuries are associated with a higher incidence of avascular necrosis and malunion. Talar neck fractures are the most common fractures. This review looks at the different types of fractures of the talus, particularly focusing on talar neck fractures. The diagnosis and management are discussed as well as the complications. PMID:28694883

A complete characterization of all-versus-nothing arguments for stabilizer states

NASA Astrophysics Data System (ADS)

Abramsky, Samson; Barbosa, Rui Soares; Carù, Giovanni; Perdrix, Simon

2017-10-01

An important class of contextuality arguments in quantum foundations are the all-versus-nothing (AvN) proofs, generalizing a construction originally due to Mermin. We present a general formulation of AvN arguments and a complete characterization of all such arguments that arise from stabilizer states. We show that every AvN argument for an n-qubit stabilizer state can be reduced to an AvN proof for a three-qubit state that is local Clifford-equivalent to the tripartite Greenberger-Horne-Zeilinger state. This is achieved through a combinatorial characterization of AvN arguments, the AvN triple theorem, whose proof makes use of the theory of graph states. This result enables the development of a computational method to generate all the AvN arguments in on n-qubit stabilizer states. We also present new insights into the stabilizer formalism and its connections with logic. This article is part of the themed issue `Second quantum revolution: foundational questions'.

Cost-Benefit Analysis of Marine Corps Search and Rescue (SAR): A Study of Alternatives for Marine Corps Air Stations at Cherry Point and Yuma

DTIC Science & Technology

2013-11-21

8999 8999 CAREER PLANNER E5 4821 4821 AVN SAFETY/STAND DIR SAFETY/STAND O4 7551 0000 AVN SAF OFF O3 7596 0000 NATOPS OFF (C-9) O4 7551 0000...NATOPS OFF (UC-35) O4 7554 0000 NATOPS OFF (H-46) O3 7562 0000 AVN OPERATIONS CLERK E4 7041 0000 S-1 ADMIN OFFICER O4 7551 0000 ADMIN OFFICER O4 7551...ASST OPS OFF O4 7562 7562 ASST OPS OFFICER O4 7506 0000 SCHED OFF O3 7562 7562 AVN OPERATIONS CHIEF E7 7041 7041 AVN OPERATIONS CLERK E4 7041

Russia and the Iranian Nuclear Program: Replay or Breakthrough? (Strategic Perspectives, no. 9)

DTIC Science & Technology

2012-03-01

Interfax– AVN Online, February 17, 2009, CEP20090217950042. 6 “Delivery of S–300 Air Defense Systems to Iran Could Be Postponed,” Interfax– AVN Online...analysis/20111115/168714032.html>. 5 “Hostilities against Iran would have unpredictable consequences—Lavrov (Part 2),” Interfax– AVN Online, November 7...Force, Death of Civilians in Iran,” Interfax– AVN Online, June 26, 2009, CEP20090626950139. This was a far cry from American reaction. Several days

[A new method of osteosynthesis in proximal humeral fractures: a new internal fixation device. Apropos of 17 cases followed over more than 2 years].

PubMed

Doursounian, L; Grimberg, J; Cazeau, C; Touzard, R C

1996-01-01

The authors describe a new internal fixation device, and report on 17 proximal humeral fractures managed with this technique. The fracture patterns, using Neer's classification were: 9 displaced three-part fractures, 4 displaced four-part fractures and 4 interior fracture dislocations (mean age of the patients: 70 years). The device is a two-part titanium device. The humeral component has a long vertical stem cemented in the humeral shaft; and a short proximal portion set at an angle of 135 degrees on the stem, with a neck and a Morse taper cone. The other part is a crown-shaped stapple, whose base is a perforated disk with a central Morse taper socket. The rim of the crown has five prongs which, together with the central socket, are impacted in the cancellous bone of the humeral head. The taper of the humeral component is inserted into the central socket of the stapple to provide fracture fixation. Tuberosities are reattached to the shaft with non absorbable sutures. Mean follow-up was 29 months. The global ratings were as follows: 4 excellent results, 6 good results, 4 fair results, 3 poor results. Mean active forward flexion: 100 degrees, and mean active external rotation 22 degrees. After exclusion of the 4 fracture-dislocations, the global rating became: 4 excellent results, 5 good results, 3 fair results, 1 poor result. Mean active forward flexion: 110 degrees and mean active external rotation: 31.5 degrees. There were no case of avascular necrosis in 13 patients. Complications requiring surgery occurred in one case: an upper protrusion of the stapple which required replacement of the stapple by a prosthetic humeral head. Other complications included: 2 asymptomatic partial protrusions of the stapple, 2 complete and two partial avascular necrosis in fracture-dislocations. Except for the fracture-dislocations our device confers several major benefits. The humeral head is preserved. Typical problems associated with joint replacement (dislocations, loosening, glenoid degeneration) are avoided. Humeral head conservation enhances healing of the tuberosities. Fixation could always be obtained, regardless of the complexity of the fracture pattern. An hemiarthroplasty (e.g. in case of avascular necrosis) is possible by the modular design of the device.

Microarray‑based screening of differentially expressed genes in glucocorticoid‑induced avascular necrosis.

PubMed

Huang, Gangyong; Wei, Yibing; Zhao, Guanglei; Xia, Jun; Wang, Siqun; Wu, Jianguo; Chen, Feiyan; Chen, Jie; Shi, Jingshen

2017-06-01

The underlying mechanisms of glucocorticoid (GC)‑induced avascular necrosis of the femoral head (ANFH) have yet to be fully understood, in particular the mechanisms associated with the change of gene expression pattern. The present study aimed to identify key genes with a differential expression pattern in GC‑induced ANFH. E‑MEXP‑2751 microarray data were downloaded from the ArrayExpress database. Differentially expressed genes (DEGs) were identified in 5 femoral head samples of steroid‑induced ANFH rats compared with 5 placebo‑treated rat samples. Gene Ontology (GO) and pathway enrichment analyses were performed upon these DEGs. A total 93 DEGs (46 upregulated and 47 downregulated genes) were identified in GC‑induced ANFH samples. These DEGs were enriched in different GO terms and pathways, including chondrocyte differentiation and detection of chemical stimuli. The enrichment map revealed that skeletal system development was interconnected with several other GO terms by gene overlap. The literature mined network analysis revealed that 5 upregulated genes were associated with femoral necrosis, including parathyroid hormone receptor 1 (PTHR1), vitamin D (1,25‑Dihydroxyvitamin D3) receptor (VDR), collagen, type II, α1, proprotein convertase subtilisin/kexin type 6 and zinc finger protein 354C (ZFP354C). In addition, ZFP354C and VDR were identified to transcription factors. Furthermore, PTHR1 was revealed to interact with VDR, and α‑2‑macroglobulin (A2M) interacted with fibronectin 1 (FN1) in the PPI network. PTHR1 may be involved in GC‑induced ANFH via interacting with VDR. A2M may also be involved in the development of GC‑induced ANFH through interacting with FN1. An improved understanding of the molecular mechanisms underlying GC‑induced ANFH may provide novel targets for diagnostics and therapeutic treatment.

New insights into the pathogenesis of glucocorticoid-induced avascular necrosis: microarray analysis of gene expression in a rat model

PubMed Central

2010-01-01

Introduction Avascular necrosis of the femoral head (ANFH) occurs variably after exposure to corticosteroids. Microvascular thrombosis is a common pathological finding. Since systemic thrombophilia is only weakly linked with ANFH, we propose that microvascular vessel pathology may be more related to local endothelial dysfunction and femoral head apoptosis. Corticosteroid effects on the endothelium and resultant apoptosis have been reported. We hypothesize that corticosteroids contribute to a differential gene expression in the femoral head in rats with early ANFH. Methods Besides bone marrow necrosis, which is a common sign in ANFH and reported in the early stages, we include the presence of apoptosis in this study as a criterion for diagnosing early disease. Forty Wistar Kyoto (WKY) rats were randomized to either a corticosteroid-treated group or an age-matched control group for six months. After sacrifice, the femoral heads were examined for ANFH. Total mRNA was extracted from femoral heads. Affymetrix exon array (Santa Clara, CA, USA) was performed on 15 selected RNA samples. Validation methods included RT-PCR and immunohistochemistry (IHC). Results Although rat exon array demonstrated a significant upregulation of 51 genes (corticosteroid(+)/ANFH(+) VS control), alpha-2-macroglobulin (A2M) gene was particularly over-expressed. Results were validated by RT-PCR and IHC. Importantly, A2M is known to share vascular, osteogenic and cartilage functions relevant for ANFH. Conclusions The findings suggest that corticosteroid-induced ANFH in rats might be mediated by A2M. Investigation of A2M as a potential marker, and a treatment target, for early ANFH should be carried out. PMID:20579363

Microarray-based screening of differentially expressed genes in glucocorticoid-induced avascular necrosis

PubMed Central

Huang, Gangyong; Wei, Yibing; Zhao, Guanglei; Xia, Jun; Wang, Siqun; Wu, Jianguo; Chen, Feiyan; Chen, Jie; Shi, Jingshen

2017-01-01

The underlying mechanisms of glucocorticoid (GC)-induced avascular necrosis of the femoral head (ANFH) have yet to be fully understood, in particular the mechanisms associated with the change of gene expression pattern. The present study aimed to identify key genes with a differential expression pattern in GC-induced ANFH. E-MEXP-2751 microarray data were downloaded from the ArrayExpress database. Differentially expressed genes (DEGs) were identified in 5 femoral head samples of steroid-induced ANFH rats compared with 5 placebo-treated rat samples. Gene Ontology (GO) and pathway enrichment analyses were performed upon these DEGs. A total 93 DEGs (46 upregulated and 47 downregulated genes) were identified in GC-induced ANFH samples. These DEGs were enriched in different GO terms and pathways, including chondrocyte differentiation and detection of chemical stimuli. The enrichment map revealed that skeletal system development was interconnected with several other GO terms by gene overlap. The literature mined network analysis revealed that 5 upregulated genes were associated with femoral necrosis, including parathyroid hormone receptor 1 (PTHR1), vitamin D (1,25-Dihydroxyvitamin D3) receptor (VDR), collagen, type II, α1, proprotein convertase subtilisin/kexin type 6 and zinc finger protein 354C (ZFP354C). In addition, ZFP354C and VDR were identified to transcription factors. Furthermore, PTHR1 was revealed to interact with VDR, and α-2-macroglobulin (A2M) interacted with fibronectin 1 (FN1) in the PPI network. PTHR1 may be involved in GC-induced ANFH via interacting with VDR. A2M may also be involved in the development of GC-induced ANFH through interacting with FN1. An improved understanding of the molecular mechanisms underlying GC-induced ANFH may provide novel targets for diagnostics and therapeutic treatment. PMID:28393228

Outcome of bone marrow instillation at fracture site in intracapsular fracture of femoral neck treated by head preserving surgery.

PubMed

Verma, Nikhil; Singh, M P; Ul-Haq, Rehan; Rajnish, Rajesh K; Anshuman, Rahul

2017-08-01

The aim of present study is to evaluate the outcome of bone marrow instillation at the fracture site in fracture of intracapsular neck femur treated by head preserving surgery. This study included 32 patients of age group 18-50 years with closed fracture of intracapsular neck femur. Patients were randomized into two groups as per the plan generated via www.randomization.com. The two groups were Group A (control), in which the fracture of intracapsular neck femur was treated by closed reduction and cannulated cancellous screw fixation, and Group B (intervention), in which additional percutaneous autologous bone marrow aspirate instillation at fracture site was done along with cannulated cancellous screw fixation. Postoperatively the union at fracture site and avascular necrosis of the femoral head were assessed on serial plain radiographs at final follow-up. Functional outcome was evaluated by Harris hip score. The average follow-up was 19.6 months. Twelve patients in each group had union and 4 patients had signs of nonunion. One patient from each group had avascular necrosis of the femoral head. The average Harris hip score at final follow-up in Group A was 80.50 and in Group B was 75.73, which was found to be not significant. There is no significant role of adding on bone marrow aspirate instillation at the fracture site in cases of fresh fracture of intracapsular neck femur treated by head preserving surgery in terms of accelerating the bone healing and reducing the incidence of femoral head necrosis. Copyright © 2017 Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. Production and hosting by Elsevier B.V. All rights reserved.

The application of PRP combined with TCP in repairing avascular necrosis of the femoral head after femoral neck fracture in rabbit.

PubMed

Zhang, X-L; Wang, Y-M; Chu, K; Wang, Z-H; Liu, Y-H; Jiang, L-H; Chen, X; Zhou, Z-Y; Yin, G

2018-02-01

In view of the high occurrence of avascular necrosis of the femoral head (ANFH) after femoral neck fracture and the difficulties in the treatment, our work aimed to explore the effects of platelet-rich plasma (PRP) combined with tri-calcium phosphate (TCP) on the repair of ANFH after femoral neck fracture and to provide reference for clinical treatment. Thirty New Zealand white rabbits were randomly divided into control group, TCP group, and PRP+TCP group. The rabbit ANFH model was established and femoral head tissues were collected. HE staining was used for histological observation. Image analysis and statistical analysis were used to calculate the New Bone Area fraction (NBA %). The levels of bone morphogenetic protein (BMP)-7, transforming growth factor (TGF)-β1, basic fibroblast growth factor (bFGF), interleukin (IL)-6 and tumor necrosis factor (TNF)-a in serum were detected by Enzyme-Linked ImmunoSorbent Assay (ELISA). The new bone area of TCP group was significantly lower than that of PRP+TCP group (p<0.05). Compared with the control group, the levels of BMP-7, TGF-β1 and bFGF were significantly increased in both TCP and PRP+TCP groups (p<0.05), and the increase in PRP+TCP group was higher than that in TCP group. TCP and PRP+TCP can both significantly reduce the content of IL-6 and TNF-a (p<0.05); however, higher decrease was found in PRP+TCP group compared with the TCP group at 8 weeks after injection. PRP combined with TCP, which can promote new bone formation and inhibit inflammatory response, showed higher efficiency in repairing ANFH than internal fixation alone.

Long-Term Effects of Atrial Ganglionated Plexi Ablation on Function and Structure of Sinoatrial and Atrioventricular Node in Canine.

PubMed

Zhang, Ming; Wang, Ximin; Xie, Xinxing; Wang, Zhongsu; Liu, Xiaoyan; Guan, Juan; Wang, Weizong; Li, Zhan; Wang, Jiangrong; Gao, Mei; Hou, Yinglong

2015-10-01

Long-term effects of ganglionated plexi (GP) ablation on sinoatrial node (SAN) and atrioventricular node (AVN) remain unclear. This study is to investigate the long-term effects of ablation of cardiac anterior right GP (ARGP) and inferior right GP (IRGP) on function and structure of SAN and AVN in canine. Thirty-two dogs were randomly divided into an operated group (n = 24) and sham-operated group (n = 8). ARGP and IRGP were ablated in operated group which was randomly divided into three subgroups according to the period of evaluation after operation (1 month, 6 months, 12 months). The functional and histological characteristics of SAN and AVN, as well as the expression of connexin (Cx) 43 and Cx 45 in SAN and AVN, were evaluated before and after ablation. Resting heart rate was increased and AVN effective refractory period was prolonged and sinus node recovery time (SNRT) and corrected SNRT were shortened immediately after ablation. These changes were reverted to preablation level after 1 month. At 1 month, ventricular rate during atrial fibrillation was slowed, atria-His intervals were prolonged, and Cx43 and Cx45 expression in SAN and AVN were downregulated. At 6 months, all changes were reverted to preablation level. The histological characteristics of SAN and AVN did not change. Ablation of ARGP and IRGP has short-term effects on function and structure of SAN and AVN rather than long-term effects, which suggests that ablation of ARGP and IRGP is safe. Atrioventricular conduction dysfunction after ablation may be related to downregulated Cx43 and Cx45 expression in AVN. © 2015 Wiley Periodicals, Inc.

Effect of interconnection between cervical vagus trunk, epicardial fat pad on sinus node function, and atrial fibrillation.

PubMed

Zhou, Qina; Zhang, Ling; Wang, Kun; Xu, Xiaoxia; Ji, Meng; Zhang, Feng; Wang, Hongli; Hou, Yuemei

2014-03-01

The epicardial fat pad (FP) integrates the autonomic innervation between the extrinsic and intrinsic cardiac autonomic nervous system and affects atrial electrophysiology and pathophysiology. Eighteen dogs were divided into two groups: sequential ablation of sinoatrial node FP (SAN-FP) and atrioventricular node FP (AVN-FP). Sinus rate (SR), atrial fibrillation (AF) inducibility, and effective refractory period (ERP) changes during electrical stimulation of the vagus trunk were detected before and after ablation. In the SAN-FP group, the SR slowing, increasing AF inducibility, and ERP shortening that induced by vagus trunk stimulation were significantly attenuated by isolated SAN-FP ablation, compared with the same group prior to ablation (all P < 0.05). Subsequent AVN-FP ablation following SAN-FP ablation almost cannot produce further attenuation during vagus trunk stimulation, compared with isolated SAN-FP ablation (P > 0.05). In the AVN-FP group, SR slowing, increasing AF inducibility, and ERP shortening that induced by vagus trunk stimulation were completely eliminated by isolated AVN-FP ablation, compared with the same group prior to ablation (all P < 0.05). Subsequent SAN-FP ablation following AVN-FP ablation produced no further attenuation, compared with isolated AVN-FP ablation (P > 0.05). A neural pathway from the cervical vagus trunk to the sinus node and atrium runs through the SAN-FP, but eventually converges at the AVN-FP and also suggested that the AVN-FP serves as an "integration center" for the SAN-FP to modulate sinus node function. The AVN-FP may play a more critical role in the initiation and maintenance of AF. ©2013 First Affilated Hospital of Xingiang Medical University Pacing and Clinical Electrophysiology ©2013 Wiley Periodicals, Inc.

Avenanthramide-C reduces the viability of MDA-MB-231 breast cancer cells through an apoptotic mechanism.

PubMed

Hastings, Jordan; Kenealey, Jason

2017-01-01

Avenanthramides (AVN) are a relatively unstudied family of phytochemicals that could be novel chemotherapeutics. These compounds, found in oats, are non-toxic to healthy cells and have been shown to reduce viability of human colon and liver cancers in vitro. However, these studies do not elucidate a molecular mechanism for individual AVN. In this study we aim to see the effects of AVN on MDA-MB-231 breast cancer cells. An MTT assay was used to determine cell viability. Staining and analysis with a flow cytometer was used to identify cell cycle progression and apoptosis. FloJo software was used to analyze the cytometric data. In all experiments, statistical significance was determined by a two-tailed t test. This study demonstrates that AVN-A, B, and C individually reduce viability in the MDA-MB-231 breast cancer cell line. AVN-C has the most potent decrease in tumor cell viability, decreasing viable cells to below 25% at 400 µM when compared to control after 96 h. We demonstrate that treatment with AVN-C causes DNA fragmentation and accumulation of over 90% of cells into a sub G 1 cell cycle population. Further, we conclude that AVN-C treated cells activate apoptosis because 97% of treated cells stain positive for annexin V while 91% have caspase-3/7 activity, a late marker of apoptosis. Breast cancer cells treated with AVN-C have a decrease in cell viability, an increase in the sub G 1 population, and stain positive for both annexin V and caspase activity, indicating that AVN-C induces apoptosis in breast cancer cells. These compounds may be able to act as chemotherapeutics as demonstrated through future in vivo studies.

Legg-Calvé-Perthes disease in a child with osteopetrosis

PubMed Central

Sims, Alex L.; Barwick, Thomas W.; Montgomery, Richard J.

2011-01-01

Osteopetrosis is a rare inherited disorder of bone causing increased bone density. Legg-Calvé-Perthes disease (LCPD), by contrast, is a more common idiopathic condition leading to variable avascular necrosis of the immature femoral head. We present a case of a 5-year-old boy presenting with these co-morbidities. We have found only one previous reference suggesting these two conditions can coexist in the literature. We discuss the basic principles of management of this interesting case. PMID:24765380

Prolongation of atrio-ventricular node conduction in a rabbit model of ischaemic cardiomyopathy: Role of fibrosis and connexin remodelling.

PubMed

Nisbet, Ashley M; Camelliti, Patrizia; Walker, Nicola L; Burton, Francis L; Cobbe, Stuart M; Kohl, Peter; Smith, Godfrey L

2016-05-01

Conduction abnormalities are frequently associated with cardiac disease, though the mechanisms underlying the commonly associated increases in PQ interval are not known. This study uses a chronic left ventricular (LV) apex myocardial infarction (MI) model in the rabbit to create significant left ventricular dysfunction (LVD) 8weeks post-MI. In vivo studies established that the PQ interval increases by approximately 7ms (10%) with no significant change in average heart rate. Optical mapping of isolated Langendorff perfused rabbit hearts recapitulated this result: time to earliest activation of the LV was increased by 14ms (16%) in the LVD group. Intra-atrial and LV transmural conduction times were not altered in the LVD group. Isolated AVN preparations from the LVD group demonstrated a significantly longer conduction time (by approximately 20ms) between atrial and His electrograms than sham controls across a range of pacing cycle lengths. This difference was accompanied by increased effective refractory period and Wenckebach cycle length, suggesting significantly altered AVN electrophysiology post-MI. The AVN origin of abnormality was further highlighted by optical mapping of the isolated AVN. Immunohistochemistry of AVN preparations revealed increased fibrosis and gap junction protein (connexin43 and 40) remodelling in the AVN of LVD animals compared to sham. A significant increase in myocyte-non-myocyte connexin co-localization was also observed after LVD. These changes may increase the electrotonic load experienced by AVN muscle cells and contribute to slowed conduction velocity within the AVN. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Measurement Space Drill Support

DTIC Science & Technology

2015-08-30

II) H-47 Block II (I) *H-47 Block II (II) AVN FVL Att (I) * AVN FVL Att (II) TRAC- MTRY F2025B Logistic Flow MS Drill Support FY15 Research...does not have to use other AVN /ground assets to cover the area, freeing these assets to perform other missions and potentially enhancing the

[Application of bilateral direct anterior approach total hip arthroplasty: a report of 22 cases].

PubMed

Tang, J; Lv, M; Zhou, Y X; Zhang, J

2017-04-18

To analyze the operation technique and the methods to avoid early complications on the learning curve for bilateral direct anterior approach (DAA) total hip arthroplasty (THA). We retrospectively studied a series of continued cases with bilateral avascular necrosis of the femoral head (AVN) or degenerative dysplastic hip and rheumatoid arthritis that were treated by DAA THA in Beijing Jishuitan Hospital. A total of 22 patients with 44 hips were analyzed from June 2014 to August 2016 in this study. There were 17 males and 5 females, and the median age was 48 years (range: 34-67 years). All the surgery was done by DAA method by two senior surgeons. The clinic characters, early surgery treatment results and complications were analyzed. We used the cementless stems in all the cases. The average operating time was (167±23) min; the average blood loss was (775±300) mL;the blood transfusion was in average (327±341) mL; the wound drainage in average was (111±73) mL. Most of the patients could move out of the bed by themselves on the first day after operation, 5 patients could walk without crutches on the first operating day, and 13 patients could squat on the third days after operation. The patients were discharged averagely 4 days after operation. We followed up all the patients for averagely 16 months (range: 8-24 months). There was no loosening or failure case in the latest follow up. In the study, 2 patients had great trochanter fracture, 2 patients had thigh pain, 4 patients had lateral femoral cutaneous nerve palsy, and 3 patients had muscle damage. The Harris scores were improved from 29±8 preoperatively to 90±3 postoperatively (P<0.01). The DAA THA can achieve faster recovery and flexible hip joint after operation. However it is a kind of surgery with high technique demanding. Carefully selected patients, and skilled technique, can help the surgeon avoid the early complications. It is associated with high complication rate in the learning curve for bilateral DAA THA.

Structural and functional alterations in the atrioventricular node and atrioventricular ring tissue in ischaemia-induced heart failure.

PubMed

Yanni, Joseph; Maczewski, Michal; Mackiewicz, Urszula; Siew, Samuel; Fedorenko, Olga; Atkinson, Andrew; Price, Marcus; Beresewicz, Andrzej; Anderson, Robert H; Boyett, Mark R; Dobrzynski, Halina

2014-07-01

Heart failure (HF) causes dysfunction of the atrioventricular node (AVN) - first or second-degree heart block is a risk factor for sudden cardiac death in HF patients. The aim of the study was to determine if HF causes remodelling of the AVN and right atrioventricular ring (RAVR). HF was induced in rats (n=4) by ligation of the proximal left coronary artery, which resulted in a large infarct of the left ventricle. Sham-operated rats (n=4) were used as controls. Eight weeks after surgery, functional experiments were performed and the hearts were frozen. The body weight of HF rats was similar to control rats, but the mean heart weight of HF rats was significantly enlarged. In HF rats compared to controls, the left ventricle was dilated, left ventricular end-diastolic pressure elevated (21.0 ± 0.6 and 5.4 ± 0.2 mm Hg), left ventricular ejection fraction reduced (0.2 ± 0.02 and 0.5 ± 0.02) and left ventricular end-systolic pressure reduced (102 ± 4.2 and 127 ± 3.1 mm Hg). In HF rats, the in vivo and in vitro PR intervals were increased (41% and 20%), as was the Wenckebach cycle length, indicative of AVN dysfunction. The collagen content was significantly increased in the AVN and RAVR indicating fibrosis. Immunolabelling of caveolin3 (cell membrane marker) showed that there was hypertrophy in HF (cell diameter was increased by 63%, 39% in AVN, RAVR). The TUNEL assay showed that the myocytes of the AVN and RAVR in HF undergo apoptotic cell death. Immunolabelling showed that expression of HCN4 was significantly decreased in the AVN and RAVR (43% and 47%) in HF. We conclude that in HF there is remodelling of the AVN and RAVR and this remodelling may explain the AVN dysfunction.

The physiopathology of avascular necrosis of the femoral head: an update.

PubMed

Guerado, Enrique; Caso, Enrique

2016-12-01

The physiopathology of the femoral head bone necrosis is similar for children and for adults. The disease is characterized by apoptosis of bone cells - bone marrow and bone forming cells-resulting in head collapse with a subsequent lesion of the overlying cartilage, and therefore flattening of the rounded surface shape of the head articulating with the acetabulum, provoking, eventually, secondary osteoarthritis. When the disease becomes clinically evident already destructive phenomena have occurred and collapse will eventually ensue. In children, because epiphyseal cartilage has growth capabilities, lost epiphyseal height can be recovered, however in adults collapse is irreversible. In this paper the physiopathology of this disease is examined as well as its implication for treatment. Prevention by genetic studies is discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Direct His bundle pacing post AVN ablation.

PubMed

Lakshmanadoss, Umashankar; Aggarwal, Ashim; Huang, David T; Daubert, James P; Shah, Abrar

2009-08-01

Atrioventricular nodal (AVN) ablation with concomitant pacemaker implantation is one of the strategies that reduce symptoms in patients with atrial fibrillation (AF). However, the long-term adverse effects of right ventricular (RV) apical pacing have led to the search for alternating sites of pacing. Biventricular pacing produces a significant improvement in functional capacity over RV pacing in patients undergoing AVN ablation. Another alternative site for pacing is direct His bundle to reduce the adverse outcome of RV pacing. Here, we present a case of direct His bundle pacing using steerable lead delivery system in a patient with symptomatic paroxysmal AF with concurrent AVN ablation.

Post-transplant femoral head avascular necrosis: a selective investigation with MRI.

PubMed

Karapinar, Levent; Gurkan, Alp; Kacar, Serdar; Polat, Omer

2007-01-01

We investigated the presence of femoral head avascular osteonecrosis (FHAVN) by a selective investigation with MRI at follow-up. A total of 331(200 men, 131 women) renal transplants were included. They were transplanted at the mean age of 31.4 (9-63) years. The mean follow-up time of all patients after transplantation was 60.6 (6-233) months, and the mean current age 36.6 (11-66) years. All transplants filled out a questionnaire on musculoskeletal symptoms and underwent a detailed clinical examination. Magnetic resonance imaging was done in cases of hip joint pain in groin, buttock, thigh and knee and in 50 asymptomatic transplants. FHAVN were identified according to Ficat Arlet classification. 43(13%) patients reported pain without previous trauma. In the clinical examination, limited ranges of motion of the hip were noted in 13 of them. FHAVN was detected in 11 of 43 patients. Disease was bilateral in two of the eleven patients. Of the 662 femoral heads, 43 were associated with hip pain whereas the remaining 619 were asymptomatic. Avascular osteonecrosis was not confirmed in the asymptomatic 100 hips with magnetic resonance imaging. A selective investigation of FHAVN may be used to diagnose in renal allograft recipients with painful hips at follow-up. With a retrospective selective analysis, the presence of FHAVN was low among renal transplantation recipients at the end of the study.

AVN-492, A Novel Highly Selective 5-HT6R Antagonist: Preclinical Evaluation.

PubMed

Ivachtchenko, Alexandre V; Okun, Ilya; Aladinskiy, Vladimir; Ivanenkov, Yan; Koryakova, Angela; Karapetyan, Ruben; Mitkin, Oleg; Salimov, Ramiz; Ivashchenko, Andrey

2017-01-01

Discovery of 5-HT6 receptor subtype and its exclusive localization within the central nervous system led to extensive investigations of its role in Alzheimer's disease, schizophrenia, and obesity. In the present study, we present preclinical evaluation of a novel highly-potent and highly-selective 5-HT6R antagonist, AVN-492. The affinity of AVN-492 to bind to 5-HT6R (Ki = 91 pM) was more than three orders of magnitude higher than that to bind to the only other target, 5-HT2BR, (Ki = 170 nM). Thus, the compound displayed great 5-HT6R selectivity against all other serotonin receptor subtypes, and is extremely specific against any other receptors such as adrenergic, GABAergic, dopaminergic, histaminergic, etc. AVN-492 demonstrates good in vitro and in vivo ADME profile with high oral bioavailability and good brain permeability in rodents. In behavioral tests, AVN-492 shows anxiolytic effect in elevated plus-maze model, prevents an apomorphine-induced disruption of startle pre-pulse inhibition (the PPI model) and reverses a scopolamine- and MK-801-induced memory deficit in passive avoidance model. No anti-obesity effect of AVN-492 was found in a murine model. The data presented here strongly indicate that due to its high oral bioavailability, extremely high selectivity, and potency to block the 5-HT6 receptor, AVN-492 is a very promising tool for evaluating the role the 5-HT6 receptor might play in cognitive and neurodegenerative impairments. AVN-492 is an excellent drug candidate to be tested for treatment of such diseases, and is currently being tested in Phase I trials.

Acidosis slows electrical conduction through the atrio-ventricular node

PubMed Central

Nisbet, Ashley M.; Burton, Francis L.; Walker, Nicola L.; Craig, Margaret A.; Cheng, Hongwei; Hancox, Jules C.; Orchard, Clive H.; Smith, Godfrey L.

2014-01-01

Acidosis affects the mechanical and electrical activity of mammalian hearts but comparatively little is known about its effects on the function of the atrio-ventricular node (AVN). In this study, the electrical activity of the epicardial surface of the left ventricle of isolated Langendorff-perfused rabbit hearts was examined using optical methods. Perfusion with hypercapnic Tyrode's solution (20% CO2, pH 6.7) increased the time of earliest activation (Tact) from 100.5 ± 7.9 to 166.1 ± 7.2 ms (n = 8) at a pacing cycle length (PCL) of 300 ms (37°C). Tact increased at shorter PCL, and the hypercapnic solution prolonged Tact further: at 150 ms PCL, Tact was prolonged from 131.0 ± 5.2 to 174.9 ± 16.3 ms. 2:1 AVN block was common at shorter cycle lengths. Atrial and ventricular conduction times were not significantly affected by the hypercapnic solution suggesting that the increased delay originated in the AVN. Isolated right atrial preparations were superfused with Tyrode's solutions at pH 7.4 (control), 6.8 and 6.3. Low pH prolonged the atrial-Hisian (AH) interval, the AVN effective and functional refractory periods and Wenckebach cycle length significantly. Complete AVN block occurred in 6 out of 9 preparations. Optical imaging of conduction at the AV junction revealed increased conduction delay in the region of the AVN, with less marked effects in atrial and ventricular tissue. Thus acidosis can dramatically prolong the AVN delay, and in combination with short cycle lengths, this can cause partial or complete AVN block and is therefore implicated in the development of brady-arrhythmias in conditions of local or systemic acidosis. PMID:25009505

Acidosis slows electrical conduction through the atrio-ventricular node.

PubMed

Nisbet, Ashley M; Burton, Francis L; Walker, Nicola L; Craig, Margaret A; Cheng, Hongwei; Hancox, Jules C; Orchard, Clive H; Smith, Godfrey L

2014-01-01

Acidosis affects the mechanical and electrical activity of mammalian hearts but comparatively little is known about its effects on the function of the atrio-ventricular node (AVN). In this study, the electrical activity of the epicardial surface of the left ventricle of isolated Langendorff-perfused rabbit hearts was examined using optical methods. Perfusion with hypercapnic Tyrode's solution (20% CO2, pH 6.7) increased the time of earliest activation (Tact) from 100.5 ± 7.9 to 166.1 ± 7.2 ms (n = 8) at a pacing cycle length (PCL) of 300 ms (37°C). Tact increased at shorter PCL, and the hypercapnic solution prolonged Tact further: at 150 ms PCL, Tact was prolonged from 131.0 ± 5.2 to 174.9 ± 16.3 ms. 2:1 AVN block was common at shorter cycle lengths. Atrial and ventricular conduction times were not significantly affected by the hypercapnic solution suggesting that the increased delay originated in the AVN. Isolated right atrial preparations were superfused with Tyrode's solutions at pH 7.4 (control), 6.8 and 6.3. Low pH prolonged the atrial-Hisian (AH) interval, the AVN effective and functional refractory periods and Wenckebach cycle length significantly. Complete AVN block occurred in 6 out of 9 preparations. Optical imaging of conduction at the AV junction revealed increased conduction delay in the region of the AVN, with less marked effects in atrial and ventricular tissue. Thus acidosis can dramatically prolong the AVN delay, and in combination with short cycle lengths, this can cause partial or complete AVN block and is therefore implicated in the development of brady-arrhythmias in conditions of local or systemic acidosis.

Fludarabine inhibits STAT1-mediated up-regulation of caspase-3 expression in dexamethasone-induced osteoblasts apoptosis and slows the progression of steroid-induced avascular necrosis of the femoral head in rats.

PubMed

Feng, Zhenhua; Zheng, Wenhao; Tang, Qian; Cheng, Liang; Li, Hang; Ni, Wenfei; Pan, Xiaoyun

2017-08-01

Steroid-induced avascular necrosis of the femoral head (SANFH) is a major limitation of long-term or excessive clinical administration of glucocorticoids. Fludarabine, which is a compound used to treat various hematological malignancies, such as chronic lymphocytic leukemia, acts by down-regulating signal transducer and activator of transcription 1 (STAT1) by inhibiting STAT1 phosphorylation in both normal and cancer cells. This study assessed the effects of fludarabine in vitro (primary murine osteoblasts) and in vivo (rat SANFH model). In vitro, pretreatment with fludarabine significantly inhibited Dexamethasone (Dex)-induced apoptosis in osteoblasts, which was examined by TUNEL staining. Treatment with Dex caused a remarkable decrease in the expression of Bcl-2; an increase in cytochrome c release; activation of BAX, caspase-9, and caspase-3; and an obvious enhancement in STAT1 phosphorylation. However, treatment resulted in the up-regulation of caspase-3 expression. Enhanced P-STAT1 activity and up-regulation of caspase-3 expression were also observed in osteoblasts. In vivo, the subchondral trabeculae in fludarabine-treated rats exhibited less bone loss and a lower ratio of empty lacunae. Taken together, our results suggest that STAT1-mediated up-regulation of caspase-3 is involved in osteoblast apoptosis induced by Dex and indicates that fludarabine may serve as a potential agent for the treatment of SANFH.

In vitro and in vivo evaluation of calcium phosphate composite scaffolds containing BMP-VEGF loaded PLGA microspheres for the treatment of avascular necrosis of the femoral head.

PubMed

Zhang, Hao-Xuan; Zhang, Xiu-Ping; Xiao, Gui-Yong; Hou, Yong; Cheng, Lei; Si, Meng; Wang, Shuai-Shuai; Li, Yu-Hua; Nie, Lin

2016-03-01

Avascular necrosis of the femoral head (ANFH) is difficult to treat due to high pressure and hypoxia, and reduced levels of growth factors such as bone morphogenetic protein (BMP), and vascular endothelial growth factor (VEGF). We generated a novel calcium phosphate (CPC) composite scaffold, which contains BMP-VEGF-loaded poly-lactic-co-glycolic acid (PLGA) microspheres (BMP-VEGF-PLGA-CPC). The BMP-VEGF-loaded microspheres have an encapsulation efficiency of 89.15% for BMP, and 78.55% for VEGF. The BMP-VEGF-PLGA-CPC scaffold also demonstrated a porosity of 62% with interconnected porous structures, and pore sizes of 219 μm and compressive strength of 6.60 MPa. Additionally, bone marrow mesenchymal stem cells (BMSCs) were seeded on scaffolds in vitro. Further characterization showed that the BMP-VEGF-PLGA-CPC scaffolds were biocompatible and enhanced osteogenesis and angiogenesis in vitro. Using a rabbit model of ANFH, BMP-VEGF-PLGA-CPC scaffolds were implanted into the bone tunnels of core decompression in the femoral head for 6 and 12 weeks. Radiographic and histological analysis demonstrated that the BMP-VEGF-PLGA-CPC scaffolds exhibited good biocompatibility, and osteogenic and angiogenic activity in vivo. These results indicate that the BMP-VEGF-PLGA-CPC scaffold may improve the therapeutic effect of core decompression surgery and be used as a treatment for ANFH. Copyright © 2015 Elsevier B.V. All rights reserved.

Forecasting Workload for Defense Logistics Agency Distribution

DTIC Science & Technology

2014-12-01

Distribution workload ...........................18 Monthly DD Sales for the four primary supply chains ( Avn , Land, Maritime, Ind HW) plotted to...average AVN Aviation BSM Business Systems Modernization CIT consumable items transfer C&E Construction and Equipment C&T Clothing...992081.437 See Figure 2 below for the graphical output of the linear regression. Monthly DD Sales for the four primary supply chains ( Avn , Land

[MODEL ESTABLISHMENT, MRI AND PATHOLOGICAL FEATURES OF EARLY STEROID-INDUCED AVASCULAR NECROSIS OF FEMORAL HEAD IN RABBIT].

PubMed

Zhang, Liyan; Sun, Xin; Tian, Dan; Xu, Rui; Lei, Hao; Al, Jinhui; Zhao, Bo; Chen, Jiying; Chai, Wei; Ma, Shoucheng; Liu, Weijia; Shen, Siyuan

2015-10-01

To establish an rabbit model of early steroid-induced avascular necrosis of the femoral head (SANFH) and evaluate its validity with MRI and pathological examination. Twenty 6-month-old rabbits (weighing, 2-3 kg) were randomly divided into 2 groups (control group and model group), 10 rabbits in each group. Dexamethasone sodium phosphate solution (10 mg/kg) was injected into bilateral gluteus in model group, and the same amount of saline was injected in control group, every 3 days for 14 times. General observation was done after modelling. Osteonecrosis was verified by pathological observation and MRI findings at 6 weeks. After 6 weeks, rabbits did not show obvious changes in control group; increased hair removal, decreased food intake, and slight limp were observed in model group. The MRI results showed normal shape of the bilateral femoral head and no abnormal signals in control group; irregular shape of the bilateral femoral head and a slice of irregular abnormal signals were observed, and necrosis and cystolization of the subchondral bone and sparse changes of trabecular bone were shown in model group. General observation from coronal section of femoral head showed smooth red cartilage surface in control group; on the contrary, the cartilage surface of the femoral head became dull, thin even visible hemorrhage under articular cartilage and necrosis of the femoral head were observed. The histopathological examination indicated that trabecular bone of the femoral head in control group was massive, thick, and close and osteocytes in the bone lacunae had normal shapes. The osseous trabecular became thinner and broken; karyopyknosis of osteocytes and bone empty lacunae could be obviously seen in model. group. The rates of empty lacunae were 8.0% ± 0.5% in control group and 49.0% ± 0.3% in model group, showing significant difference (t = 21.940, P = 0.000). Establishing a model of early SANFH through injecting short-term, shock, and high dose of dexamethasone, and it can been evaluated effectively with MRI and pathological examination.

Histologic study of the effects of chemoembolization with preloaded doxorubicin beads in patients with hepatocellular carcinoma.

PubMed

Zurera, L J; Espejo, J J; Lombardo, S; Marchal, T; Muñoz, M C; Canis, M; Montero, J L

2015-01-01

To determine the degree of tumor necrosis in surgical specimens of hepatocellular carcinomas treated with microspheres preloaded with doxorubicin and to analyze the relationship between the degree of necrosis and a) morphologic factors and b) imaging biomarkers. We studied the livers of 21 patients who had undergone selective arterial chemoembolization with DC beads (Biocompatibles, UK) before receiving liver transplants. Imaging techniques detected 43 nodules (mean size, 25 mm). Angiography showed 25 hypervascularized nodules, 12 slightly vascularized nodules, and 6 avascular nodules. A total of 81 hepatocellular carcinomas (mean size, 15 mm) were detected in the specimens: two were capsular and two had vascular infiltration. The mean degree of necrosis after chemoembolization was 39%; necrosis was greater than 60% in 28 hepatocellular carcinomas and less than 60% in 52. The degree of necrosis correlated significantly with the time elapsed between the last chemoembolization treatment and liver transplantation (the degree of necrosis decreased as time increased), with the number of nodules in the specimen, and with capsular infiltration. When imaging techniques detected 1 or 2 nodules, there was a greater probability of achieving greater than 90% necrosis. No relation with the degree of necrosis achieved was found for the size of the nodules detected at imaging, the enhancement pattern, or the number of chemoembolization treatments. The degree of necrosis achieved depends on the time spent on the waiting list, on the number of nodules in the specimen, and on whether capsular infiltration is present. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

The Fall of the General Staff Model: Towards a Third Generation U.S. Army Staff Theory

DTIC Science & Technology

2013-05-23

Officer AVN : Aviation M&M: Movement and Manuever CBRN: Chemical, Biological, Radiological, Nuclear MP: Military Police 128Department of the Army...Missile Defense KM: Knowledge Management AVN : Aviation CMD GRP: Command Group M&M: Movement And Maneuver CA: Civil Affairs NETOPS: Network...ADA: Air Defense Artillery LNO: Liaison Officer AVN : Aviation M&M: Movement and Manuever CBRN: Chemical, Biological

Department of Defense Systems Engineering FY 2012 Annual Report

DTIC Science & Technology

2013-03-01

by the Utility Helicopter PMO, is utilizing the latest Defense Acquisition Guidelines and previously approved PEO AVN SEP examples to develop all...efforts. As a whole, all of PEO AVN Program Management Offices understand the importance of systems engineering. They stress the continued use of...established SE guidelines, practices and procedures throughout our acquisition processes. PEO AVN , working with the AMRDEC SE Division, has

An isolated dorso-medial dislocation of navicular bone: A case report.

PubMed

Singh, Varun Kumar; Kashyap, Abhishek; Vargaonkar, Gauresh; Kumar, Ramesh

2015-03-01

An isolated dislocation of tarsal navicular is extremely rare injury. Usually it is associated with fracture of navicular itself or other tarsal bones of foot along with disruption of medial or lateral column of foot. Mechanism of injury is complex but usually a severe abduction force is required to produce such injury in a planter flexed foot. A 30 year old male presented with isolated navicular dislocation. Management required open reduction and fixation with k-wires. These injuries have specific complications including avascular necrosis of navicular and post-traumatic arthritis.

The Proposal and Early Results of Capitate Forage as a New Treatment Method for Kienböck's Disease.

PubMed

Bekler, Halil Ibrahim; Erdag, Yiğit; Gumustas, Seyit Ali; Pehlivanoglu, Gökhan

2013-12-01

Kienböck's disease is a type of avascular necrosis which disrupts the biomechanics of the wrist as a result of the changes it creates in the lunate bone. Its treatment generally consists of osteotomies intended to relieve the pressure on the bone, pedicle bone grafting applications aiming to increase bone blood supply, and salvage procedures. Capitate forage is a safe and simple-to-apply surgical treatment method which is intended to enhance neovascularization of the lunate much like a radius osteotomy or core decompression.

Katrina Historical Page - Office of Satellite and Product Operations

Science.gov Websites

» Disclaimer » Web Linking Policy » Use of Data and Products » FAQs: Imagery Contact Us Services Argos DCS . Floater Imagery August 28/1745Z to 29/0245Z: Image: AVN | BD | FT | IR | IR2 | JSL | RB | RGB | VIS | WV Image (w/ Latitude & Longitude): AVN | BD | FT | IR | IR2 | JSL | RB | RGB | VIS | WV Loop: AVN | BD

Exosomes secreted from mutant-HIF-1α-modified bone-marrow-derived mesenchymal stem cells attenuate early steroid-induced avascular necrosis of femoral head in rabbit.

PubMed

Li, Haile; Liu, Danping; Li, Chen; Zhou, Shanjian; Tian, Dachuan; Xiao, Dawei; Zhang, Huan; Gao, Feng; Huang, Jianhua

2017-12-01

Mesenchymal stem cells (MSCs)-derived exosomes exhibit protective effects on damaged or diseased tissues. Hypoxia-inducible factor 1α (HIF-1α) plays a critical role in bone development. However, HIF-1α is easily biodegradable under normoxic conditions. The bone-marrow-derived mesenchymal stem cells (BMSCs) were transfected with adenovirus carrying triple point-mutations (amino acids 402, 564, and 803) in the HIF-1α coding sequence (CDS). The mutant HIF-1α can efficiently express functional proteins under normoxic conditions. To date, no study has reported the role of exosomes secreted by mutant HIF-1α modified BMSCs in the recovery of the early steroid-induced avascular necrosis of femoral head (SANFH). In this study, we firstly analyzed exosomes derived from BMSCs modified by mutant (BMSC-Exos MU ) or wild-type HIF-1α (BMSC-Exos WT ). In vitro, we investigated the osteogenic differentiation capacity of BMSCs modified by BMSC-Exos MU or BMSC-Exos WT , and the angiogenesis effects of BMSC-Exos MU and BMSC-Exos WT on human umbilical vein endothelial cells (HUVECs). Besides, the healing of the femoral head was also assessed in vivo. We found that the potential of osteogenic differentiation of BMSCs treated with BMSC-Exos MU was higher than the wild-type group in vitro. In addition, BMSC-Exos MU stimulated the proliferation, migration, and tube formation of HUVECs in a dose-dependent manner. Compared with the BMSC-Exos WT or PBS control group, the injection of BMSC-Exos MU into the necrosis region markedly accelerated the bone regeneration and angiogenesis, which were indicated by the increased trabecular reconstruction and microvascular density. Taken together, our data suggest that BMSC-Exos MU facilitates the repair of SANFH by enhancing osteogenesis and angiogenesis. © 2017 International Federation for Cell Biology.

9/11 and Canadian Special Operations Forces: How 40 Selected Men Indelibly Influenced the Future of the Force

DTIC Science & Technology

2013-05-23

Terrorism strategy/plan and an unresolved dialogue surrounding special operations aviation (SO Avn ) deficiencies are but two specific examples of...Regiment-like sister unit (the Canadian Special Operations Regiment (CSOR)) is created, an expanded SO Avn capability is formed (427 Special Operations...an adequate SO Avn Squadron under command, maturing CJIRU and CSOR sister units and lately a small but effective SOF training organization.127

Russian Ballistic Missile Defense: Rhetoric and Reality

DTIC Science & Technology

2015-06-01

articles/eu-places-sanctions-on-russian-oligarchs-1406749975. 33. “U.S. Sanctions Not to Impact Almaz-Antei Concern Operations,” Interfax- AVN , July...in Production 2015; New S-300/400 SAM Production Site,” Interfax- AVN , May 14, 2014. 70. Aleksey Nikolskiy, “Rakety izgotovleny, zhdyom vykhoda v...Aerospace Defence Chief,” Interfax- AVN , BBC Monitoring Former Soviet Union, September 5, 2012. 99. “Pervye S-500 mogut postupit v rossiyskie voyska v

Prospective assessment of bone turnover and clinical bone diseases after allogeneic hematopoietic stem-cell transplantation.

PubMed

Petropoulou, Anna D; Porcher, Raphael; Herr, Andrée-Laure; Devergie, Agnès; Brentano, Thomas Funck; Ribaud, Patricia; Pinto, Fernando O; Rocha, Vanderson; Peffault de Latour, Régis; Orcel, Philippe; Socié, Gérard; Robin, Marie

2010-06-15

Bone complications after hematopoietic stem-cell transplantation (HSCT) are relatively frequent. Evaluation of biomarkers of bone turnover and dual energy x-ray absorptiometry (DEXA) are not known in this context. We prospectively evaluated bone mineral density, biomarkers of bone turnover, and the cumulative incidence of bone complications after allogeneic HSCT. One hundred forty-six patients were included. Bone mineral density was measured by DEXA 2-month and 1-year post-HSCT. The markers of bone turnover were serum C-telopeptide (C-TP), 5 tartrate-resistant acid phosphatase (bone resorption), and osteocalcin (bone formation) determined pre-HSCT and 2 months and 1 year thereafter. Potential association between osteoporosis at 2 months, osteoporotic fracture or avascular necrosis and, individual patient's characteristics and biologic markers were tested. C-TP was high before and 2 months after transplant. At 2 months, DEXA detected osteoporosis in more than half the patients tested. Male sex, median age less than or equal to 15 years, and abnormal C-TP before HSCT were risk factors significantly associated with osteoporosis. Three-year cumulative incidences of fractures and avascular necrosis were 8% and 11%, respectively. Children were at higher risk of fracture, whereas corticosteroid treatment duration was a significant risk factor for developing a clinical bone complication post-HSCT. Bone complications and osteoporosis are frequent after HSCT. Bone biologic markers and DEXA showed that subclinical bone abnormalities appeared early post-HSCT. The risk factors, age, gender, and C-TP easily available at the time of transplantation were identified. Biphosphonates should probably be given to patients with those risk factors.

Angiogenesis and bone regeneration by allogeneic mesenchymal stem cell intravenous transplantation in rabbit model of avascular necrotic femoral head.

PubMed

Li, Zhanghua; Liao, Wen; Zhao, Qiang; Liu, Ming; Xia, Wei; Yang, Yi; Shao, Ningsheng

2013-07-01

To explore the feasibility of allogeneic mesenchymal stem cells (MSCs) transplanted intravenously for angiogenesis and bone repair in a rabbit model of avascular necrosis of femoral head (ANFH). Forty-five rabbits were randomized into three groups: a blank control group (without treatment), a necrotic control group (ANFH induced but without therapy), and an MSC transplantation group (ANFH induced and treated with MSC transplantation). The biopsies, blood sampling, and imaging examinations were performed on each animal at different time points (2, 4, and 6 wk). To monitor angiogenesis and bone repair progress, examinations included real-time polymerase chain reaction, Western blot analysis, x-ray, computed tomography, Masson trichrome staining, picrosirius red staining, and immunohistochemical staining. Necrosis and bone collapse were observed in bilateral femoral heads of necrotic rabbits of the necrotic control group, whereas the femoral head morphology was generally restored in the MSC transplantation group. The mRNA levels of Cbfa1, BMP, VEGF, and OPN in bone tissue were significantly higher in the MSC transplantation group than in the necrotic control group. In addition, the total protein amount of Cbfa1 in the MSC transplantation group was also significantly higher than that in the necrotic control group (P < 0.05). Intravenous transplantation of allogeneic MSCs can promote vascular and bone regeneration in the necrotic region of the femoral head in a rabbit model of ANFH. The results of our study suggest that the intravenous transplantation of MSCs could be a potential and minimally invasive treatment option for ANFH patients. Copyright © 2013 Elsevier Inc. All rights reserved.

Pro-osteogenic effects of fibrin glue in treatment of avascular necrosis of the femoral head in vivo by hepatocyte growth factor-transgenic mesenchymal stem cells

PubMed Central

2014-01-01

Background Autologous transplantation of modified mesenchymal stem cells (MSCs) is a promising candidate for the treatment of the refractory clinical disease, avascular necrosis of the femoral head (ANFH). Our previous attempts by compounding MSCs with medical fibrin glue to treat ANFH in animal model have achieved excellent effects. However, the underlying molecular mechanism is unclear, especially on the transgenic gene expression. Methods Rabbit MSCs were isolated and compounded with fibrin glue. Following degrading of fibrin glue, proliferation, viability, expression of transgenic hepatocyte growth factor gene as well as osteogenic differentiation of MSCs were evaluated together with that of uncompounded MSCs. Fibrin glue-compounded MSCs were transplanted into the lesion of ANFH model, and the therapeutic efficacy was compared with uncompounded MSCs. One-Way ANOVA was used to determine the statistical significance among treatment groups. Results Fibrin glue compounding will not affect molecular activities of MSCs, including hepatocyte growth factor (HGF) secretion, cell proliferation and viability, and osteogenic differentiation in vitro. When applying fibrin glue-compounded MSCs for the therapy of ANFH in vivo, fibrin glue functioned as a drug delivery system and provided a sustaining microenvironment for MSCs which helped the relatively long-term secretion of HGF in the femoral head lesion and resulted in improved therapeutic efficacy when compared with uncompounded MSCs as indicated by hematoxylin-eosin staining and immunohistochemistry of osteocalcin, CD105 and HGF. Conclusion Transplantation of fibrin glue-compounding MSCs is a promising novel method for ANFH therapy. PMID:24885252

Clinical predictors of challenging atrioventricular node ablation procedure for rate control in patients with atrial fibrillation.

PubMed

Polin, Baptiste; Behar, Nathalie; Galand, Vincent; Auffret, Vincent; Behaghel, Albin; Pavin, Dominique; Daubert, Jean-Claude; Mabo, Philippe; Leclercq, Christophe; Martins, Raphael P

2017-10-15

Atrioventricular node (AVN) ablation is usually a simple procedure but may sometimes be challenging. We aimed at identifying pre-procedural clinical predictors of challenging AVN ablation. Patients referred for AVN ablation from 2009 to 2015 were retrospectively included. Baseline clinical data, procedural variables and outcomes of AVN ablation were collected. A "challenging procedure" was defined 1) total radiofrequency delivery to get persistent AVN block≥400s, 2) need for left-sided arterial approach or 3) failure to obtain AVN ablation. 200 patients were included (71±10years). A total of 37 (18.5%) patients had "challenging" procedures (including 9 failures, 4.5%), while 163 (81.5%) had "non-challenging" ablations. In multivariable analysis, male sex (Odds ratio (OR)=4.66, 95% confidence interval (CI): 1.74-12.46), body mass index (BMI, OR=1.08 per 1kg/m 2 , 95%CI 1.01-1.16), operator experience (OR=0.40, 95%CI 0.17-0.94), and moderate-to-severe tricuspid regurgitation (TR, OR=3.65, 95%CI 1.63-8.15) were significant predictors of "challenging" ablations. The proportion as a function of number of predictors was analyzed (from 0 to 4, including male sex, operator inexperience, a BMI>23.5kg/m 2 and moderate-to-severe TR). There was a gradual increase in the risk of "challenging" procedure with the number of predictors by patient (No predictor: 0%; 1 predictor: 6.3%; 2 predictors: 16.5%; 3 predictors: 32.5%; 4 predictors: 77.8%). Operator experience, male sex, higher BMI and the degree of TR were independent predictors of "challenging" AVN ablation procedure. The risk increases with the number of predictors by patient. Copyright © 2017. Published by Elsevier B.V.

Warfighter Information Network-Tactical Increment 3 (WIN-T Inc 3)

DTIC Science & Technology

2013-12-01

T vehicles employed at BCT, Fires, (Ch-1) WIN-T Inc 3 December 2013 SAR April 16, 2014 16:49:41 UNCLASSIFIED 13 AVN , BfSB, and select force...passengers and crew from small arms fire, mines, IED and other anti-vehicle/ personnel threats. AVN , BfSB, and select force pooled assets...small arms fire, mines, IED and other anti-vehicle/ personnel threats. AVN , BfSB, and select force pooled assets operating within the

Family as a Total Package: Restoring and Enhancing Psychological Health for Citizen Soldiers and Families

DTIC Science & Technology

2012-03-01

En Co (‐) (Sapper) Festus 220 EN Co (HORIZ) Co I, 27 R&R Bn (RSP) Ft. Leonard Wood HQ , 35 En Bde Co C, 1/106  Avn HHC, Det 1, 1/106  Avn Det 1, Co D...1/106  Avn Det 1, Co E, 1/106  Avn 7 Civil Support Team (WMD) HQ, 140 Regt (RTI) 2 Bn, 140 Regt (RTI)(GS) Fredericktown  Det 1, 1138 En Co (Sapper...735 QM Co Co B (‐), 1/134  Avn 229 Med Bn (Multifunction) 138 FSC, 1/138 In Det 40, OSACOM Co F, 27 R&R Bn (RSP) Jefferson City  Ike Skelton Training

[Legg-Calvé-Perthes disease].

PubMed

Wiig, Ola; Svenningsen, Svein; Terjesen, Terje

2011-05-20

Legg-Calvé-Perthes disease is characterized by avascular necrosis of the head of the femur. This article deals with the epidemiology, possible causes, treatment and prognostic factors connected with the disease. The article is based on a non-systematic literature search and own clinical practice, with special emphasis on a Norwegian countrywide study of children with Legg-Calvé-Perthes disease. The incidence of Legg-Calvé-Perthes disease varies in different countries and regions. Those who are older than six years at the time of diagnosis and have over 50% femoral head necrosis have a worse prognosis than younger children where the necrosis is less extensive. Treatment has been discussed extensively over the past 100 years, and still varies considerably. The Norwegian countrywide investigation showed that the results in children who were over six years at the time of diagnosis and had more than 50% femoral head necrosis were significantly better after varus femoral osteotomy than after physiotherapy or orthosis. This agrees with the only other prospective study that has been published. Operative treatment should be considered in children who are six years old or older and have over 50% femoral head necrosis when the diagnosis Legg-Calvé-Perthes disease is made. Those who are younger than six years at the time of diagnosis or who have less than 50% femoral head necrosis should be treated symptomatically. Abduction orthosis has no place in the treatment of Legg-Calvé-Perthes disease.

Electrophysiological properties of myocytes isolated from the mouse atrioventricular node: L-type ICa, IKr, If, and Na-Ca exchange

PubMed Central

Choisy, Stéphanie C; Cheng, Hongwei; Orchard, Clive H; James, Andrew F; Hancox, Jules C

2015-01-01

The atrioventricular node (AVN) is a key component of the cardiac pacemaker-conduction system. This study investigated the electrophysiology of cells isolated from the AVN region of adult mouse hearts, and compared murine ionic current magnitude with that of cells from the more extensively studied rabbit AVN. Whole-cell patch-clamp recordings of ionic currents, and perforated-patch recordings of action potentials (APs), were made at 35–37°C. Hyperpolarizing voltage commands from −40 mV elicited a Ba2+-sensitive inward rectifier current that was small at diastolic potentials. Some cells (Type 1; 33.4 ± 2.2 pF; n = 19) lacked the pacemaker current, If, whilst others (Type 2; 34.2 ± 1.5 pF; n = 21) exhibited a clear If, which was larger than in rabbit AVN cells. On depolarization from −40 mV L-type Ca2+ current, ICa,L, was elicited with a half maximal activation voltage (V0.5) of −7.6 ± 1.2 mV (n = 24). ICa,L density was smaller than in rabbit AVN cells. Rapid delayed rectifier (IKr) tail currents sensitive to E-4031 (5 μmol/L) were observed on repolarization to −40 mV, with an activation V0.5 of −10.7 ± 4.7 mV (n = 8). The IKr magnitude was similar in mouse and rabbit AVN. Under Na-Ca exchange selective conditions, mouse AVN cells exhibited 5 mmol/L Ni-sensitive exchange current that was inwardly directed negative to the holding potential (−40 mV). Spontaneous APs (5.2 ± 0.5 sec−1; n = 6) exhibited an upstroke velocity of 37.7 ± 16.2 V/s and ceased following inhibition of sarcoplasmic reticulum Ca2+ release by 1 μmol/L ryanodine, implicating intracellular Ca2+ cycling in murine AVN cell electrogenesis. PMID:26607172

Holographic optical coherence imaging of tumor spheroids

NASA Astrophysics Data System (ADS)

Yu, P.; Mustata, M.; Turek, J. J.; French, P. M. W.; Melloch, M. R.; Nolte, D. D.

2003-07-01

We present depth-resolved coherence-domain images of living tissue using a dynamic holographic semiconductor film. An AlGaAs photorefractive quantum-well device is used in an adaptive interferometer that records coherent backscattered (image-bearing) light from inside rat osteogenic sarcoma tumor spheroids up to 1 mm in diameter in vitro. The data consist of sequential holographic image frames at successive depths through the tumor represented as a visual video "fly-through." The images from the tumor spheroids reveal heterogeneous structures presumably caused by necrosis and microcalcifications characteristic of human tumors in their early avascular growth.

Infantile and juvenile lunatomalacia.

PubMed

Irisarri, C; Kalb, K; Ribak, S

2010-09-01

Lunatomalacia or avascular necrosis of the lunate in children is a rare disease not described by Kienböck. It is somewhat surprising that the term Kienböck's disease has been used to describe this disease of the lunate in children. We report our experience in 13 cases and review the literature. In children under 12, the prognosis is very good after immobilization alone. Persistent symptoms may indicate surgery, probably radial shortening, in some older teenagers although the outcome appears better than in adults. We suggest the term lunatomalacia to describe this disorder, in recognition of the term originally used by Kienböck.

Slipped upper femoral epiphysis: imaging of complications after treatment.

PubMed

Tins, B; Cassar-Pullicino, V; McCall, I

2008-01-01

Slipped upper femoral epiphysis (SUFE) is a multifactorial condition usually affecting adolescents. Obesity is one risk factor, and as this is increasing the incidence of SUFE is likely to rise. Diagnosis and treatment are usually straightforward and carried out by orthopaedic surgeons. However, the recognition of post-treatment complications poses a much greater challenge. This article focuses on possible complications of surgical treatment of SUFE particularly. Chondrolysis, avascular necrosis, as well as other complications of treatment and conditions leading to premature osteoarthritis are discussed. Checklists for a systematic approach to post-treatment imaging are provided.

Non-pharmacologic management of sickle cell pain.

PubMed

Bodhise, Paul Brown; Dejoie, Marjorie; Brandon, Zemoria; Simpkins, Stanley; Ballas, Samir K

2004-06-01

Patients with sickle cell disease (SCD) suffer from both acute and chronic pain. The latter includes avascular necrosis of the hip joints mostly in the adult population. It has a negative impact on the quality of life of affected individuals and is often associated with depression, disability, unemployment and dependence on opioid analgesics. In this study, we show that a non-pharmacologic approach to management with deep tissue/deep pressure massage therapy technique, including neuromuscular trigger point treatment with acupressure, in patients with SCD has a salutary effect on pain relief and quality of life. Copyright 2004 Taylor and Francis Ltd

Avascular necrosis of the femoral heads in a red panda (Ailurus fulgens fulgens): possible Legg-Calve-Perthes disease.

PubMed

Delclaux, María; Talavera, Covadonga; López, Manuel; Sánchez, Jose Miguel; García, María Isabel

2002-09-01

A 17-mo-old captive-born female red panda (Ailurus fulgens fulgens) presented with a sudden onset of lameness in its left hind leg was diagnosed radiographically as having possible severe, bilateral Legg-Calve-Perthes disease with fracture of the great trochanter of the left femur. Surgical repair of the fracture was performed using pins and a tension band wire through a lateral approach to the hip. This is the first case reported at Madrid Zoo-Aquarium, where 63 individuals have been bred over 15 yr.

Diagnostic dilemma of degenerative joint disease, chronic avascular necrosis or metastasis in planar Tc-99m-methylene diphosphonate planar skeletal scintigraphy excluded by single positron emission computed tomography/computed tomography.

PubMed

Jain, Tarun Kumar; Phulsunga, Rohit Kumar; Basher, Rajender Kumar; Kumar, Narendra; Bhattacharya, Anish; Mittal, Bhagwant Rai

2015-01-01

We present a 71-year-old male patient subjected to skeletal scintigraphy for metastasis work up of prostate cancer. Whole body planar images revealed a solitary focal tracer uptake in left femoral head mimicking as solitary metastatic focus. Single positron emission computed tomography/computed tomography images localized this increased tracer uptake to the subchondral cysts with minimal sclerosis in left femur head with no decrease in size of femur head and was reported as (degenerative joint disease).

Diagnostic dilemma of degenerative joint disease, chronic avascular necrosis or metastasis in planar Tc-99m-methylene diphosphonate planar skeletal scintigraphy excluded by single positron emission computed tomography/computed tomography

PubMed Central

Jain, Tarun Kumar; Phulsunga, Rohit Kumar; Basher, Rajender Kumar; Kumar, Narendra; Bhattacharya, Anish; Mittal, Bhagwant Rai

2015-01-01

We present a 71-year-old male patient subjected to skeletal scintigraphy for metastasis work up of prostate cancer. Whole body planar images revealed a solitary focal tracer uptake in left femoral head mimicking as solitary metastatic focus. Single positron emission computed tomography/computed tomography images localized this increased tracer uptake to the subchondral cysts with minimal sclerosis in left femur head with no decrease in size of femur head and was reported as (degenerative joint disease). PMID:26170582

Atlas of computerized blood flow analysis in bone disease.

PubMed

Gandsman, E J; Deutsch, S D; Tyson, I B

1983-11-01

The role of computerized blood flow analysis in routine bone scanning is reviewed. Cases illustrating the technique include proven diagnoses of toxic synovitis, Legg-Perthes disease, arthritis, avascular necrosis of the hip, fractures, benign and malignant tumors, Paget's disease, cellulitis, osteomyelitis, and shin splints. Several examples also show the use of the technique in monitoring treatment. The use of quantitative data from the blood flow, bone uptake phase, and static images suggests specific diagnostic patterns for each of the diseases presented in this atlas. Thus, this technique enables increased accuracy in the interpretation of the radionuclide bone scan.

All-versus-nothing proofs with n qubits distributed between m parties

NASA Astrophysics Data System (ADS)

Cabello, Adán; Moreno, Pilar

2010-04-01

All-versus-nothing (AVN) proofs show the conflict between Einstein, Podolsky, and Rosen’s elements of reality and the perfect correlations of some quantum states. Given an n-qubit state distributed between m parties, we provide a method with which to decide whether this distribution allows an m-partite AVN proof specific for this state using only single-qubit measurements. We apply this method to some recently obtained n-qubit m-particle states. In addition, we provide all inequivalent AVN proofs with less than nine qubits and a minimum number of parties.

AVN-101: A Multi-Target Drug Candidate for the Treatment of CNS Disorders.

PubMed

Ivachtchenko, Alexandre V; Lavrovsky, Yan; Okun, Ilya

2016-05-25

Lack of efficacy of many new highly selective and specific drug candidates in treating diseases with poorly understood or complex etiology, as are many of central nervous system (CNS) diseases, encouraged an idea of developing multi-modal (multi-targeted) drugs. In this manuscript, we describe molecular pharmacology, in vitro ADME, pharmacokinetics in animals and humans (part of the Phase I clinical studies), bio-distribution, bioavailability, in vivo efficacy, and safety profile of the multimodal drug candidate, AVN-101. We have carried out development of a next generation drug candidate with a multi-targeted mechanism of action, to treat CNS disorders. AVN-101 is a very potent 5-HT7 receptor antagonist (Ki = 153 pM), with slightly lesser potency toward 5-HT6, 5-HT2A, and 5HT-2C receptors (Ki = 1.2-2.0 nM). AVN-101 also exhibits a rather high affinity toward histamine H1 (Ki = 0.58 nM) and adrenergic α2A, α2B, and α2C (Ki = 0.41-3.6 nM) receptors. AVN-101 shows a good oral bioavailability and facilitated brain-blood barrier permeability, low toxicity, and reasonable efficacy in animal models of CNS diseases. The Phase I clinical study indicates the AVN-101 to be well tolerated when taken orally at doses of up to 20 mg daily. It does not dramatically influence plasma and urine biochemistry, nor does it prolong QT ECG interval, thus indicating low safety concerns. The primary therapeutic area for AVN-101 to be tested in clinical trials would be Alzheimer's disease. However, due to its anxiolytic and anti-depressive activities, there is a strong rational for it to also be studied in such diseases as general anxiety disorders, depression, schizophrenia, and multiple sclerosis.

AVN-101: A Multi-Target Drug Candidate for the Treatment of CNS Disorders

PubMed Central

Ivachtchenko, Alexandre V.; Lavrovsky, Yan; Okun, Ilya

2016-01-01

Lack of efficacy of many new highly selective and specific drug candidates in treating diseases with poorly understood or complex etiology, as are many of central nervous system (CNS) diseases, encouraged an idea of developing multi-modal (multi-targeted) drugs. In this manuscript, we describe molecular pharmacology, in vitro ADME, pharmacokinetics in animals and humans (part of the Phase I clinical studies), bio-distribution, bioavailability, in vivo efficacy, and safety profile of the multimodal drug candidate, AVN-101. We have carried out development of a next generation drug candidate with a multi-targeted mechanism of action, to treat CNS disorders. AVN-101 is a very potent 5-HT7 receptor antagonist (Ki = 153 pM), with slightly lesser potency toward 5-HT6, 5-HT2A, and 5HT-2C receptors (Ki = 1.2–2.0 nM). AVN-101 also exhibits a rather high affinity toward histamine H1 (Ki = 0.58 nM) and adrenergic α2A, α2B, and α2C (Ki = 0.41–3.6 nM) receptors. AVN-101 shows a good oral bioavailability and facilitated brain-blood barrier permeability, low toxicity, and reasonable efficacy in animal models of CNS diseases. The Phase I clinical study indicates the AVN-101 to be well tolerated when taken orally at doses of up to 20 mg daily. It does not dramatically influence plasma and urine biochemistry, nor does it prolong QT ECG interval, thus indicating low safety concerns. The primary therapeutic area for AVN-101 to be tested in clinical trials would be Alzheimer’s disease. However, due to its anxiolytic and anti-depressive activities, there is a strong rational for it to also be studied in such diseases as general anxiety disorders, depression, schizophrenia, and multiple sclerosis. PMID:27232215

Production of hydroxycinnamoyl anthranilates from glucose in Escherichia coli

PubMed Central

2013-01-01

Background Oats contain hydroxycinnamoyl anthranilates, also named avenanthramides (Avn), which have beneficial health properties because of their antioxidant, anti-inflammatory, and antiproliferative effects. The microbial production of hydroxycinnamoyl anthranilates is an eco-friendly alternative to chemical synthesis or purification from plant sources. We recently demonstrated in yeast (Saccharomyces cerevisiae) that coexpression of 4-coumarate: CoA ligase (4CL) from Arabidopsis thaliana and hydroxycinnamoyl/benzoyl-CoA/anthranilate N-hydroxycinnamoyl/benzoyltransferase (HCBT) from Dianthus caryophyllusenabled the biological production of several cinnamoyl anthranilates upon feeding with anthranilate and various cinnamates. Using engineering strategies to overproduce anthranilate and hydroxycinnamates, we describe here an entire pathway for the microbial synthesis of two Avns from glucose in Escherichia coli. Results We first showed that coexpression of HCBT and Nt4CL1 from tobacco in the E. coli anthranilate-accumulating strain W3110 trpD9923 allowed the production of Avn D [N-(4′-hydroxycinnamoyl)-anthranilic acid] and Avn F [N-(3′,4′-dihydroxycinnamoyl)-anthranilic acid] upon feeding with p-coumarate and caffeate, respectively. Moreover, additional expression in this strain of a tyrosine ammonia-lyase from Rhodotorula glutinis (RgTAL) led to the conversion of endogenous tyrosine into p-coumarate and resulted in the production of Avn D from glucose. Second, a 135-fold improvement in Avn D titer was achieved by boosting tyrosine production using two plasmids that express the eleven genes necessary for tyrosine synthesis from erythrose 4-phosphate and phosphoenolpyruvate. Finally, expression of either the p-coumarate 3-hydroxylase Sam5 from Saccharothrix espanensis or the hydroxylase complex HpaBC from E. coli resulted in the endogenous production of caffeate and biosynthesis of Avn F. Conclusion We established a biosynthetic pathway for the microbial production of valuable hydroxycinnamoyl anthranilates from an inexpensive carbon source. The proposed pathway will serve as a platform for further engineering toward economical and sustainable bioproduction of these pharmaceuticals and other related aromatic compounds. PMID:23806124

At the Atrioventricular Crossroads: Dual Pathway Electrophysiology in the Atrioventricular Node and its Underlying Heterogeneities

PubMed Central

George, Sharon A; Faye, N Rokhaya; Murillo-Berlioz, Alejandro; Lee, K Benjamin; Trachiotis, Gregory D; Efimov, Igor R

2017-01-01

The atrioventricular node (AVN) is a complex structure that performs a variety of functions in the heart. The AVN is primarily an electrical gatekeeper between the atria and ventricles and introduces a delay between atrial and ventricular excitation, allowing for efficient ventricular filling. The AVN is composed of several compartments that safely transmit electrical excitation from the atria to the ventricles via the fast or slow pathways. There are many electrophysiological differences between these pathways, including conduction time and electrical refractoriness, that increase the predisposition of the atrioventricular junction to arrhythmias such as atrioventricular nodal re-entrant tachycardia. These varied electrophysiological characteristics of the fast and slow pathways stem from their unique structural and molecular composition (tissue and cellular geometry, ion channels and gap junctions). This review summarises the structural and molecular heterogeneities of the human AVN and how they result in electrophysiological variations and arrhythmias. PMID:29326832

Sildenafil improves blood perfusion in steroid-induced avascular necrosis of femoral head in rabbits via a protein kinase G-dependent mechanism.

PubMed

Song, Qichun; Ni, Jianlong; Jiang, Hongyuan; Shi, Zhibin

2017-10-01

The aim of the study were to evaluate the effect of sildenafil against avascular necrosis of femoral head (ANFH) in a rabbit model, and to study the role of protein kinase G (PKG) pathway and vascular endothelial growth factor (VEGF) in ANFH. Three weeks after inducing ANFH with methylprednisolone injection, 45 female adult New Zealand white rabbits were divided into three groups and treated as follows: group SI received daily intraperitoneal sildenafil with a dose of 10 mg/kg per day; group SD received daily sildenafil identically to group SI plus auricular vein injection DT3 (a specific PKG inhibitor); group NS received only normal saline. The blood perfusion function in the femoral head was measured by perfusion MRI and ink artery infusion. Bilateral femora heads were examined histopathologically for the presence of osteonecrosis; VEGF of tissue was examined by Western blot analysis; cGMP level and PKG activity were also measured. The incidence of ANFH in SI group was significantly lower than that observed in NS and SD groups (p < 0.05). VEGF in SI group was increased compared to NS group. cGMP level and PKG activity were also significantly different between NS and SI group (p < 0.05). However, these effects of sildenafil in SD group were all markedly inhibited by the administration of DT3 compared to SI group. Sildenafil appear to increase the perfusion of femoral head by up-regulating VEGF through PKG pathway. The increased perfusion of femoral head could prevent ANFH. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

Surgeon-Based 3D Printing for Microvascular Bone Flaps.

PubMed

Taylor, Erin M; Iorio, Matthew L

2017-07-01

Background  Three-dimensional (3D) printing has developed as a revolutionary technology with the capacity to design accurate physical models in preoperative planning. We present our experience in surgeon-based design of 3D models, using home 3D software and printing technology for use as an adjunct in vascularized bone transfer. Methods  Home 3D printing techniques were used in the design and execution of vascularized bone flap transfers to the upper extremity. Open source imaging software was used to convert preoperative computed tomography scans and create 3D models. These were printed in the surgeon's office as 3D models for the planned reconstruction. Vascularized bone flaps were designed intraoperatively based on the 3D printed models. Results  Three-dimensional models were created for intraoperative use in vascularized bone flaps, including (1) medial femoral trochlea (MFT) flap for scaphoid avascular necrosis and nonunion, (2) MFT flap for lunate avascular necrosis and nonunion, (3) medial femoral condyle (MFC) flap for wrist arthrodesis, and (4) free fibula osteocutaneous flap for distal radius septic nonunion. Templates based on the 3D models allowed for the precise and rapid contouring of well-vascularized bone flaps in situ, prior to ligating the donor pedicle. Conclusions  Surgeon-based 3D printing is a feasible, innovative technology that allows for the precise and rapid contouring of models that can be created in various configurations for pre- and intraoperative planning. The technology is easy to use, convenient, and highly economical as compared with traditional send-out manufacturing. Surgeon-based 3D printing is a useful adjunct in vascularized bone transfer. Level of Evidence  Level IV. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Progression of a Fracture Site Impaction as a Prognostic Indicator of Impacted Femoral Neck Fracture Treated with Multiple Pinning

PubMed Central

Yoon, Pil Whan; Shin, Young Ho; Yoo, Jeong Joon; Yoon, Kang Sup

2012-01-01

Background We evaluated the clinical and radiologic results of impacted femoral neck fractures treated with multiple pinning and determined the influence of the progression of impaction at the fracture site on clinical outcome. Methods There were 34 patients with a mean age of 65.5 years. The mean follow-up period was 3.4 years. Progression of fracture site impaction was measured using an articulo-trochanteric distance index and the percentage decrease in the articulo-trochanteric distance index between follow-up intervals. The failure of treatment was clarified as non-union and avascular necrosis. Other characteristics of the patients, including mean waiting time for surgery, preoperative Singh index score, and body mass index, were also measured to evaluate the influence on the clinical outcome of surgery. Results There were 6 fractures which were not treated successfully (3 non-union, 8.8% and 3 avascular necrosis, 8.8%). The mean percentage decrease of the articulo-trochanteric distance index within the first 6 weeks after surgery was 4.5% in the successful group and 25.1% in the failure group (p < 0.001). There was also a significant mean percentage decrease in the articulo-trochanteric distance index between 6 weeks and 3 months (p < 0.001). Conclusions Primary stabilization with Knowles pins for impacted femoral neck fractures had a reasonable clinical outcome with low morbidity. Despite a significant difference of a mean percentage decrease in the articulo-trochanteric distance index between the successful group and the failure group, we could not verify it as a risk factor for failure of treatment because the odds ratio was not statistically significant. PMID:22379557

Progression of a fracture site impaction as a prognostic indicator of impacted femoral neck fracture treated with multiple pinning.

PubMed

Yoon, Pil Whan; Shin, Young Ho; Yoo, Jeong Joon; Yoon, Kang Sup; Kim, Hee Joong

2012-03-01

We evaluated the clinical and radiologic results of impacted femoral neck fractures treated with multiple pinning and determined the influence of the progression of impaction at the fracture site on clinical outcome. There were 34 patients with a mean age of 65.5 years. The mean follow-up period was 3.4 years. Progression of fracture site impaction was measured using an articulo-trochanteric distance index and the percentage decrease in the articulo-trochanteric distance index between follow-up intervals. The failure of treatment was clarified as non-union and avascular necrosis. Other characteristics of the patients, including mean waiting time for surgery, preoperative Singh index score, and body mass index, were also measured to evaluate the influence on the clinical outcome of surgery. There were 6 fractures which were not treated successfully (3 non-union, 8.8% and 3 avascular necrosis, 8.8%). The mean percentage decrease of the articulo-trochanteric distance index within the first 6 weeks after surgery was 4.5% in the successful group and 25.1% in the failure group (p < 0.001). There was also a significant mean percentage decrease in the articulo-trochanteric distance index between 6 weeks and 3 months (p < 0.001). Primary stabilization with Knowles pins for impacted femoral neck fractures had a reasonable clinical outcome with low morbidity. Despite a significant difference of a mean percentage decrease in the articulo-trochanteric distance index between the successful group and the failure group, we could not verify it as a risk factor for failure of treatment because the odds ratio was not statistically significant.

Bone mesenchymal stem cells co-expressing VEGF and BMP-6 genes to combat avascular necrosis of the femoral head

PubMed Central

Liao, Hongxing; Zhong, Zhixiong; Liu, Zhanliang; Li, Liangping; Ling, Zemin; Zou, Xuenong

2018-01-01

The aim of the present study was to investigate the potential of bone mesenchymal stem cells (BMSCs) treated with a combination of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-6 (BMP-6) genes for the treatment of avascular necrosis of the femoral head (ANFH). Rat BMSCs were isolated and purified using a density gradient centrifugation method. The purity and characteristics of the BMSCs were detected by cell surface antigens identification using flow cytometry. The experimental groups were administered with one of the following adeno-associated virus (AAV) vector constructs: AAV-green fluorescent protein (AAV-GFP), AAV-BMP-6, AAV-VEGF or AAV-VEGF-BMP-6. The expression of VEGF and BMP-6 was detected by reverse transcription-quantitative polymerase chain reaction, western blotting and ELISA assays. The effects of VEGF and BMP-6 on BMSCs were evaluated by angiogenic and osteogenic assays. The transfected BMSCs were combined with a biomimetic synthetic scaffold poly lactide-co-glycolide (PLAGA) and they were then subcutaneously implanted into nude mice. After four weeks, the implants were analyzed with histology and subsequent immunostaining to evaluate the effects of BMSCs on blood vessel and bone formation in vivo. In the AAV-VEGF-BMP-6 group, the expression levels of VEGF and BMP-6 were significantly increased and human umbilical vein endothelial cells tube formation was significantly enhanced compared with other groups. Capillaries and bone formation in the AAV-VEGF-BMP-6 group was significantly higher compared with the other groups. The results of the present study suggest that BMSCs expressing both VEGF and BMP-6 induce an increase in blood vessels and bone formation, which provides theoretical support for ANFH gene therapy. PMID:29399103

Bone mesenchymal stem cells co-expressing VEGF and BMP-6 genes to combat avascular necrosis of the femoral head.

PubMed

Liao, Hongxing; Zhong, Zhixiong; Liu, Zhanliang; Li, Liangping; Ling, Zemin; Zou, Xuenong

2018-01-01

The aim of the present study was to investigate the potential of bone mesenchymal stem cells (BMSCs) treated with a combination of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-6 (BMP-6) genes for the treatment of avascular necrosis of the femoral head (ANFH). Rat BMSCs were isolated and purified using a density gradient centrifugation method. The purity and characteristics of the BMSCs were detected by cell surface antigens identification using flow cytometry. The experimental groups were administered with one of the following adeno-associated virus (AAV) vector constructs: AAV-green fluorescent protein (AAV-GFP), AAV-BMP-6, AAV-VEGF or AAV-VEGF-BMP-6. The expression of VEGF and BMP-6 was detected by reverse transcription-quantitative polymerase chain reaction, western blotting and ELISA assays. The effects of VEGF and BMP-6 on BMSCs were evaluated by angiogenic and osteogenic assays. The transfected BMSCs were combined with a biomimetic synthetic scaffold poly lactide-co-glycolide (PLAGA) and they were then subcutaneously implanted into nude mice. After four weeks, the implants were analyzed with histology and subsequent immunostaining to evaluate the effects of BMSCs on blood vessel and bone formation in vivo . In the AAV-VEGF-BMP-6 group, the expression levels of VEGF and BMP-6 were significantly increased and human umbilical vein endothelial cells tube formation was significantly enhanced compared with other groups. Capillaries and bone formation in the AAV-VEGF-BMP-6 group was significantly higher compared with the other groups. The results of the present study suggest that BMSCs expressing both VEGF and BMP-6 induce an increase in blood vessels and bone formation, which provides theoretical support for ANFH gene therapy.

Complex proximal humeral fractures: a prospective study of 22 cases treated using the "Bilboquet" device.

PubMed

Doursounian, L; Kilinc, A; Cherrier, B; Nourissat, G

2011-02-01

Despite recent improvements in surgical devices, complex proximal humerus fractures internal fixation still encounters frequent mechanical failures. The aim of this study was to confirm that the Bilboquet device (a design mimicking the cup-and-ball game) helps solving mechanical difficulties associated with these fractures internal fixation and to present a simplified version of the original surgical procedure. This non-randomised prospective study included 22 fractures in 22 patients, mean age: 70 years. According to the Neer classification there were three-part fractures in seven cases and four-part fractures in 15 cases. Fractures were all reduced and treated by internal fixation in a simplified surgical procedure using the Bilboquet device. Mean postoperative follow-up was 34 months. The mean Constant score was 66 and the weighted Constant score was 86. Mean active forward elevation was 108° and mean active external rotation was 28°. No per- or postoperative complications occurred. Initial reduction of the tuberosity was incomplete in four cases. Union was obtained in all fractures. There was no secondary tilting of the head, and no migration or pseudarthrosis of the tuberosities. Five patients developed postoperative avascular necrosis of the humeral head. The Bilboquet staple component provides a supporting platform for the entire humeral head area. This peripheral stabilization associated with tension band wiring explains the lack of secondary displacement in these cases. Although the Bilboquet device provides a solution to the mechanical problems of complex fractures of the proximal humerus, it does not solve the problem of secondary avascular necrosis of the humeral head, which occurred in 23% of the patients in this series and in 33% of patients in the four-part fractures subgroup. IV (non-randomised prospective study). Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Limited Area Predictability: Is There A Limit To The Operational Usefulness of A Lam

NASA Astrophysics Data System (ADS)

Mesinger, F.

The issue of the limited area predictability in the context of the operational experience of the Eta Model, driven by the LBCs of the NCEP global spectral (Avn) model, is examined. The traditional view is that "the contamination at the lateral boundaries ... limits the operational usefulness of the LAM beyond some forecast time range". In the case of the Eta this contamination consists not only of the lower resolution of the Avn LBCs and the much discussed mathematical "lateral boundary error", but also of the use of the LBCs of the previous Avn run, at 0000 and 1200 UTC estimated to amount to about an 8 h loss in accuracy. Looking for the signs of the Eta accuracy in relative terms falling behind that of the Avn we have examined the trend of the Eta vs Avn precipitation scores, the rms fits to raobs of the two models as a function of time, and the errors of these models at extended forecast times in placing the centers of major lows. In none of these efforts, some including forecasts out to 84 h, we were able to notice signs of the Eta accuracy being visibly affected by the inflow of the lateral boundary errors. It is therefore hypothesized that some of the Eta design features compensate for the increasing influence of the Avn LBC errors. Candidate features are discussed, with the eta coordinate being a contender to play a major role. This situation being possible for the pair of models discussed, existence of a general limit for the operational usefulness of a LAM seems questionable.

Electrophysiological properties of myocytes isolated from the mouse atrioventricular node: L-type ICa, IKr, If, and Na-Ca exchange.

PubMed

Choisy, Stéphanie C; Cheng, Hongwei; Orchard, Clive H; James, Andrew F; Hancox, Jules C

2015-11-01

The atrioventricular node (AVN) is a key component of the cardiac pacemaker-conduction system. This study investigated the electrophysiology of cells isolated from the AVN region of adult mouse hearts, and compared murine ionic current magnitude with that of cells from the more extensively studied rabbit AVN. Whole-cell patch-clamp recordings of ionic currents, and perforated-patch recordings of action potentials (APs), were made at 35-37°C. Hyperpolarizing voltage commands from -40 mV elicited a Ba(2+)-sensitive inward rectifier current that was small at diastolic potentials. Some cells (Type 1; 33.4 ± 2.2 pF; n = 19) lacked the pacemaker current, If, whilst others (Type 2; 34.2 ± 1.5 pF; n = 21) exhibited a clear If, which was larger than in rabbit AVN cells. On depolarization from -40 mV L-type Ca(2+) current, IC a,L, was elicited with a half maximal activation voltage (V0.5) of -7.6 ± 1.2 mV (n = 24). IC a,L density was smaller than in rabbit AVN cells. Rapid delayed rectifier (IK r) tail currents sensitive to E-4031 (5 μmol/L) were observed on repolarization to -40 mV, with an activation V0.5 of -10.7 ± 4.7 mV (n = 8). The IK r magnitude was similar in mouse and rabbit AVN. Under Na-Ca exchange selective conditions, mouse AVN cells exhibited 5 mmol/L Ni-sensitive exchange current that was inwardly directed negative to the holding potential (-40 mV). Spontaneous APs (5.2 ± 0.5 sec(-1); n = 6) exhibited an upstroke velocity of 37.7 ± 16.2 V/s and ceased following inhibition of sarcoplasmic reticulum Ca(2+) release by 1 μmol/L ryanodine, implicating intracellular Ca(2+) cycling in murine AVN cell electrogenesis. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

MyoR Modulates Cardiac Conduction by Repressing Gata4

PubMed Central

Harris, John P.; Bhakta, Minoti; Bezprozvannaya, Svetlana; Wang, Lin; Lubczyk, Christina; Olson, Eric N.

2014-01-01

The cardiac conduction system coordinates electrical activation through a series of interconnected structures, including the atrioventricular node (AVN), the central connection point that delays impulse propagation to optimize cardiac performance. Although recent studies have uncovered important molecular details of AVN formation, relatively little is known about the transcriptional mechanisms that regulate AV delay, the primary function of the mature AVN. We identify here MyoR as a novel transcription factor expressed in Cx30.2+ cells of the AVN. We show that MyoR specifically inhibits a Cx30.2 enhancer required for AVN-specific gene expression. Furthermore, we demonstrate that MyoR interacts directly with Gata4 to mediate transcriptional repression. Our studies reveal that MyoR contains two nonequivalent repression domains. While the MyoR C-terminal repression domain inhibits transcription in a context-dependent manner, the N-terminal repression domain can function in a heterologous context to convert the Hand2 activator into a repressor. In addition, we show that genetic deletion of MyoR in mice increases Cx30.2 expression by 50% and prolongs AV delay by 13%. Taken together, we conclude that MyoR modulates a Gata4-dependent regulatory circuit that establishes proper AV delay, and these findings may have wider implications for the variability of cardiac rhythm observed in the general population. PMID:25487574

A cellular automata model for avascular solid tumor growth under the effect of therapy

NASA Astrophysics Data System (ADS)

Reis, E. A.; Santos, L. B. L.; Pinho, S. T. R.

2009-04-01

Tumor growth has long been a target of investigation within the context of mathematical and computer modeling. The objective of this study is to propose and analyze a two-dimensional stochastic cellular automata model to describe avascular solid tumor growth, taking into account both the competition between cancer cells and normal cells for nutrients and/or space and a time-dependent proliferation of cancer cells. Gompertzian growth, characteristic of some tumors, is described and some of the features of the time-spatial pattern of solid tumors, such as compact morphology with irregular borders, are captured. The parameter space is studied in order to analyze the occurrence of necrosis and the response to therapy. Our findings suggest that transitions exist between necrotic and non-necrotic phases (no-therapy cases), and between the states of cure and non-cure (therapy cases). To analyze cure, the control and order parameters are, respectively, the highest probability of cancer cell proliferation and the probability of the therapeutic effect on cancer cells. With respect to patterns, it is possible to observe the inner necrotic core and the effect of the therapy destroying the tumor from its outer borders inwards.

Effects of Wenyangbushen formula on the expression of VEGF, OPG, RANK and RANKL in rabbits with steroid-induced femoral head avascular necrosis.

PubMed

Song, Hong-Mei; Wei, Ying-Chen; Li, Nan; Wu, Bin; Xie, Na; Zhang, Kun-Mu; Wang, Shi-Zhong; Wang, He-Ming

2015-12-01

The present study aimed to investigate the effects of Wenyangbushen formula on the mRNA and protein expression levels of vascular endothelial growth factor (VEGF), osteoprotegerin (OPG), receptor activator of nuclear factor (NF)‑κβ ligand (RANK), and RANK ligand (RANKL) in a rabbit model of steroid‑induced avascular necrosis of the femoral head (SANFH). The present study also aimed to examine the potential mechanism underlying the effect of this formula on the treatment of SANFH. A total of 136 New Zealand rabbits were randomly divided into five groups: Normal group, model group, and three groups treated with the traditional Chinese medicine (TCM), Wenyangbushen decoction, at a low, moderate and high dose, respectively. The normal group and positive control group were intragastrically administered with saline. The TCM groups were treated with Wenyangbushen decoction at the indicated dosage. Following treatment for 8 weeks, the mRNA and protein expression levels of VEGF, OPG, RANK and RANKL in the femoral head tissues were determined using reverse transcription‑quantitative polymerase chain reaction and western blot analyses, respectively. The data revealed that Wenyangbushen decoction effectively promoted the growth of bone cells, osteoblasts and chondrocytes, and prevented cell apoptosis in the SANFH. The mRNA and protein expression levels of OPG and VEGF were increased, while the levels of RANK and RANKL were reduced in the necrotic tissue of the model group, compared with those in the normal rabbits. Wenyangbushen treatment prevented these changes, manifested by an upregulation in the expression levels of VEGF and OPG, and downregulation in the expression levels of RANK and RANKL in a dose‑dependent manner. It was concluded that treatment with Wenyangbushen formula alleviated necrosis of the femoral head induced by steroids. It was observed to promote bone cell, osteoblast and chondrocyte growth, as well as prevent cell apoptosis. In addition, it upregulated the expression levels of OPG and VEGF, and inhibited the expression levels of RANK and RANKL. These results suggest the potential use of Wenyangbushen formula as a possible approach for the effective treatment of SANFH.

Identification of nodal tissue in the living heart using rapid scanning fiber-optics confocal microscopy and extracellular fluorophores.

PubMed

Huang, Chao; Kaza, Aditya K; Hitchcock, Robert W; Sachse, Frank B

2013-09-01

Risks associated with pediatric reconstructive heart surgery include injury of the sinoatrial node (SAN) and atrioventricular node (AVN), requiring cardiac rhythm management using implantable pacemakers. These injuries are the result of difficulties in identifying nodal tissues intraoperatively. Here we describe an approach based on confocal microscopy and extracellular fluorophores to quantify tissue microstructure and identify nodal tissue. Using conventional 3-dimensional confocal microscopy we investigated the microstructural arrangement of SAN, AVN, and atrial working myocardium (AWM) in fixed rat heart. AWM exhibited a regular striated arrangement of the extracellular space. In contrast, SAN and AVN had an irregular, reticulated arrangement. AWM, SAN, and AVN tissues were beneath a thin surface layer of tissue that did not obstruct confocal microscopic imaging. Subsequently, we imaged tissues in living rat hearts with real-time fiber-optics confocal microscopy. Fiber-optics confocal microscopy images resembled images acquired with conventional confocal microscopy. We investigated spatial regularity of tissue microstructure from Fourier analysis and second-order image moments. Fourier analysis of fiber-optics confocal microscopy images showed that the spatial regularity of AWM was greater than that of nodal tissues (37.5 ± 5.0% versus 24.3 ± 3.9% for SAN and 23.8 ± 3.7% for AVN; P<0.05). Similar differences of spatial regularities were revealed from second-order image moments (50.0 ± 7.3% for AWM versus 29.3 ± 6.7% for SAN and 27.3 ± 5.5% for AVN; P<0.05). The study demonstrates feasibility of identifying nodal tissue in living heart using extracellular fluorophores and fiber-optics confocal microscopy. Application of the approach in pediatric reconstructive heart surgery may reduce risks of injuring nodal tissues.

Talar Fractures in Children: A Possible Injury After Go-Karting Accidents.

PubMed

Kamphuis, Saskia J M; Meijs, Claartje M E M; Kleinveld, Sanne; Diekerhof, Carel H; van der Heijden, Frank H W M

2015-01-01

Go-karting is an increasingly popular high-energy sport enjoyed by both children and adults. Because of the speeds involved, accidents involving go-karts can lead to serious injury. We describe 6 talar fractures in 4 patients that resulted from go-karting accidents. Talar fractures can cause severe damage to the tibiotalar joint, talocalcaneal or subtalar joint, and the talonavicular joint. This damage can, in turn, lead to complications such as avascular necrosis, arthritis, nonunion, delayed union, and neuropraxia, which have the potential to cause long-term disability in a child. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Ventricular fibrillation occurring after atrioventricular node ablation despite minimal difference between pre- and post-ablation heart rates.

PubMed

Squara, F; Theodore, G; Scarlatti, D; Ferrari, E

2017-02-01

We report the case of an 82-year-old man presenting with ventricular fibrillation (VF) occurring acutely after atrioventricular node (AVN) ablation. This patient had severe valvular cardiomyopathy, chronic atrial fibrillation (AF), and underwent prior to the AVN ablation a biventricular implantable cardiac defibrillator positioning. The VF was successfully cardioverted with one external electrical shock. What makes this presentation original is that the pre-ablation spontaneous heart rate in AF was slow (84 bpm), and that VF occurred after ablation despite a minimal heart rate drop of only 14 bpm. VF is the most feared complication of AVN ablation, but it had previously only been described in case of acute heart rate drop after ablation of at least 30 bpm (and more frequently>50 bpm). This case report highlights the fact that VF may occur after AVN ablation regardless of the heart rate drop, rendering temporary fast ventricular pacing mandatory whatever the pre-ablation heart rate. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Bone-preserving total hip arthroplasty in avascular necrosis of the hip-a matched-pairs analysis.

PubMed

Merschin, David; Häne, Richard; Tohidnezhad, Mersedeh; Pufe, Thomas; Drescher, Wolf

2018-07-01

Short-stem hip arthroplasty has the potential advantage of femoral bone stock preservation, especially in view of the expected revisions in the often relatively young patients. Despite short-stem hip prosthesis are increasingly used for total hip arthroplasty, there are no sufficient mid- and long-term results especially for patients with avascular femoral head osteonecrosis. The present study investigates mid-term functional results as well as the revision rate following implantation of a short-stem prosthesis. In the period 06/2005 until 12/2013, a total of 351 short-stem hip prostheses were implanted. The study included 331 complete data sets. A retrospective analysis was performed using the Oxford Hip Score. All revisions were registered. In a total of 331 prostheses, the Oxford Hip Score was "excellent" in 66.2%, "good" in 12.7%, "fair" in 13.0%, and "poor" in 8.2% with a mean follow-up of 57.4 months (SD ± 29.8; range 24-115). In 26 cases, aseptic osteonecrosis of the hip was the indication (7.9%). The Oxford Hip Score was "excellent" in 66.7%, "good" in 0.0%, "fair" in 20.8%, and "poor" in 12.5%. The cumulated five year survival rate was 96.7%. In mid-term observation, the Metha® short-stem prosthesis shows no disadvantage in functional outcome and in survival time compared to a standard hip stem. Providing a correct indication, the Metha® short stem is a valuable option in total hip arthroplasty for younger patients with avascular osteonecrosis of the femoral head. Evaluation has shown no significant differences between aseptic osteonecrosis and other indications.

Characterization of L-type calcium channel activity in atrioventricular nodal myocytes from rats with streptozotocin-induced Diabetes mellitus

PubMed Central

Yuill, Kathryn H; Al Kury, Lina T; Howarth, Frank Christopher

2015-01-01

Cardiovascular complications are common in patients with Diabetes mellitus (DM). In addition to changes in cardiac muscle inotropy, electrical abnormalities are also commonly observed in these patients. We have previously shown that spontaneous cellular electrical activity is altered in atrioventricular nodal (AVN) myocytes, isolated from the streptozotocin (STZ) rat model of type-1 DM. In this study, utilizing the same model, we have characterized the changes in L-type calcium channel activity in single AVN myocytes. Ionic currents were recorded from AVN myocytes isolated from the hearts of control rats and from those with STZ-induced diabetes. Patch-clamp recordings were used to assess the changes in cellular electrical activity in individual myocytes. Type-1 DM significantly altered the cellular characteristics of L-type calcium current. A reduction in peak ICaL density was observed, with no corresponding changes in the activation parameters of the current. L-type calcium channel current also exhibited faster time-dependent inactivation in AVN myocytes from diabetic rats. A negative shift in the voltage dependence of inactivation was also evident, and a slowing of restitution parameters. These findings demonstrate that experimentally induced type-1 DM significantly alters AVN L-type calcium channel cellular electrophysiology. These changes in ion channel activity may contribute to the abnormalities in cardiac electrical function that are associated with high mortality levels in patients with DM. PMID:26603460

Warfighter Information Network-Tactical Increment 3 (WIN-T Inc 3)

DTIC Science & Technology

2015-12-01

than 1 seconds. Force Protection Armor required to protect personnel operating WIN-T vehicles employed at BCT, Fires, AVN , BfSB, and select force...21, 2016 18:26:36 UNCLASSIFIED 12 Acronyms and Abbreviations AOR - Area of Responsibility ATH - At-the-Halt ATO - Approval to Operate AVN

Design Space Exploration and Optimization Using Modern Ship Design Tools

DTIC Science & Technology

2014-06-01

Model Editor will open again. Aviation Facilities Indicator should be set to MINOR AVN since we are required to have two helicopters in our design. The...other options are NONE and MAJOR AVN . The former should be selected if no aviation facilities are required and the latter should be chosen only for

Evolution of Army Attack Aviation: A Chaotic Coupled Pendulums Analogy

DTIC Science & Technology

2013-05-23

forward of the FLOT for 36 minutes.32 Ground Campaign: 4-229 AVN Deep Attack, 26-27 February With the commencement of the ground campaign on 24......battalions worth of tanks and armored personnel carriers while receiving no damage to 4-229 AVN aircraft.34 Prior planning, training, and command

Experimental Demonstration of the Einstein-Podolsky-Rosen Steering Game Based on the All-Versus-Nothing Proof

NASA Astrophysics Data System (ADS)

Sun, Kai; Xu, Jin-Shi; Ye, Xiang-Jun; Wu, Yu-Chun; Chen, Jing-Ling; Li, Chuan-Feng; Guo, Guang-Can

2014-10-01

Einstein-Podolsky-Rosen (EPR) steering, a generalization of the original concept of "steering" proposed by Schrödinger, describes the ability of one system to nonlocally affect another system's states through local measurements. Some experimental efforts to test EPR steering in terms of inequalities have been made, which usually require many measurement settings. Analogy to the "all-versus-nothing" (AVN) proof of Bell's theorem without inequalities, testing steerability without inequalities would be more strong and require less resources. Moreover, the practical meaning of steering implies that it should also be possible to store the state information on the side to be steered, a result that has not yet been experimentally demonstrated. Using a recent AVN criterion for two-qubit entangled states, we experimentally implement a practical steering game using quantum memory. Furthermore, we develop a theoretical method to deal with the noise and finite measurement statistics within the AVN framework and apply it to analyze the experimental data. Our results clearly show the facilitation of the AVN criterion for testing steerability and provide a particularly strong perspective for understanding EPR steering.

Glycosphingolipid-functionalized nanoparticles recapitulate CD169-dependent HIV-1 uptake and trafficking in dendritic cells

NASA Astrophysics Data System (ADS)

Yu, Xinwei; Feizpour, Amin; Ramirez, Nora-Guadalupe P.; Wu, Linxi; Akiyama, Hisashi; Xu, Fangda; Gummuluru, Suryaram; Reinhard, Björn M.

2014-06-01

Ganglioside GM3, a host-derived glycosphingolipid incorporated in the membrane of human immunodeficiency virus-1 (HIV-1) viral particles, mediates interactions between HIV-1 and Siglec1/CD169, a protein expressed on dendritic cells (DCs). Such interactions, which seem to be independent of viral envelope glycoprotein gp120, are poorly understood. Here we develop a model system consisting of self-assembled artificial virus nanoparticles (AVNs) that are free of viral glycoproteins or other host-derived glycolipids and glycoproteins. These plasmonic AVNs contain a membrane of defined composition wrapped around a solid metal core. GM3-containing AVNs are captured by CD169-expressing HeLa cells or mature DCs, and are sequestered within non-lysosomal tetraspanin-positive compartments. This distribution is reminiscent of CD169-dependent HIV-1 sequestration in mature DCs. Our results highlight GM3-CD169 binding as a gp120-independent signal for sequestration and preservation of HIV-1 infectivity. They also indicate that plasmonic AVNs offer improved features over liposome-based systems and represent a versatile tool for probing specific virus-cell interactions.

Acute desensitization of acetylcholine and endothelin-1 activated inward rectifier K+ current in myocytes from the cardiac atrioventricular node.

PubMed

Choisy, Stéphanie C M; James, Andrew F; Hancox, Jules C

2012-07-06

The atrioventricular node (AVN) is a vital component of the pacemaker-conduction system of the heart, co-ordinating conduction of electrical excitation from cardiac atria to ventricles and acting as a secondary pacemaker. The electrical behaviour of the AVN is modulated by vagal activity via activation of muscarinic potassium current, IKACh. However, it is not yet known if this response exhibits 'fade' or desensitization in the AVN, as established for the heart's primary pacemaker--the sinoatrial node. In this study, acute activation of IKACh in rabbit single AVN cells was investigated using whole-cell patch clamp at 37 °C. 0.1-1 μM acetylcholine (ACh) rapidly activated a robust IKACh in AVN myocytes during a descending voltage-ramp protocol. This response was inhibited by tertiapin-Q (TQ; 300 nM) and by the M2 muscarinic ACh receptor antagonist AFDX-116 (1 μM). During sustained ACh exposure the elicited IKACh exhibited bi-exponential fade (τf of 2.0 s and τs 76.9 s at -120 mV; 1 μM ACh). 10 nM ET-1 elicited a current similar to IKACh, which faded with a mono-exponential time-course (τ of 52.6 s at -120 mV). When ET-1 was applied following ACh, the ET-1 activated response was greatly attenuated, demonstrating that ACh could desensitize the response to ET-1. For neither ACh nor ET-1 was the rate of current fade dependent upon the initial response magnitude, which is inconsistent with K+ flux mediated changes in electrochemical driving force as the underlying mechanism. Collectively, these findings demonstrate that TQ sensitive inwardly rectifying K+ current in cardiac AVN cells, elicited by M2 muscarinic receptor or ET-1 receptor activation, exhibits fade due to rapid desensitization. Copyright © 2012 Elsevier Inc. All rights reserved.

Posterior hip dislocation in a non-professional football player: a case report and review of the literature.

PubMed

Bakalakos, Matthaios; Benetos, Ioannis S; Rozis, Meletios; Vlamis, John; Pneumaticos, Spiros

2018-06-02

The majority of injuries during a football game are contusions, sprains and/or strains in the thigh, knee and ankle. Hip dislocations account for 2-5% of total hip dislocations, and they can be posterior or anterior. Major complications of traumatic hip dislocation include avascular necrosis of femoral head, secondary osteoarthritis, sciatic nerve injury and heterotopic ossification. On the occasion of a case of a 33-year-old football player, who suffered a posterior hip dislocation, associated with a posterior wall fracture of the acetabulum, while playing football, we review the literature and analyze the various mechanisms of injury, the possible complications and the management including surgery and rehabilitation.

Why Sustainers Should Care About the Targeting Process

DTIC Science & Technology

2016-02-29

1200 T: Recon GOLD / 13B SP TBD AWT/ AVN T: SPT Convoy GOLD / 13B SP 1315 / 1415 T: SPT Convoy Turani SP 1115 T: SPT Convoy GOLD / 13B SP 1315 / 1415 T...on the lookout for a white Ford observed). Legend A/DACG = Arrival/departure airfield control group AWT/ AVN = Air weapons teams/aviation BSA

Simple Computation of the Heat of Formation and Density from Theoretically Predicted Values

DTIC Science & Technology

2012-09-01

ARSENAL AL 35898-5249 2 US ARMY AVN & MIS CMND ATTN AMSRD AMR PS PT L PLEDGER ATTN AMSRD AMR PS PT M MORRISON BLDG 7120...REDSTONE ARSENAL AL 35898 2 US ARMY AVN & MIS CMND ATTN AMSRD ARL PS PT G DRAKE ATTN AMSRD ARL PS PT N MATHIS BLDG 7120

The DEDS: DSTO’s Environmental-Data Server for Research Applications

DTIC Science & Technology

2013-07-01

AccuWeather.com, 2010. Available from: http:// www.accuweather.com/ [cited 15 June 2010]. 44. National Oceanic and Atmospheric Administration, /data/gfs- avn ...hi. Available from: http://nomads.ncdc.noaa.gov/data/gfs- avn -hi/ [cited 15 June 2010]. 45. Wang, Y., L.R. Leung, J.L. McGregor, D.-K. Lee, W.-C

Operational Overreach or Academic Under Reach: Preventing Culmination Through Sustainment

DTIC Science & Technology

2013-12-10

Third US Army, 1 August 1944-9 May 1945. Volume 1 & 2 reproduced jointly by 652nd Engineering (TOPO) Bn., CO. B, 942nd Engineer AVN ., (TOPO) Bn...942nd Engineer AVN ., (TOPO) Bn. 26Peter Dye, “To What Extent Were Logistics Shortages Responsible for Patton’s Culmination on the Meuse in 1944

Distance Learning: The Impact of Not Being a Resident Student

DTIC Science & Technology

2016-03-01

63xx 1 Acquisitions Off. 51xx 8 Contracting 64xx 79 Flight Surgeon 2302 1 Avn . Supply Off. 66xx 27 Medical 60xx 1 Finance 65xx 24 JAG 2500 7 Air C&C...21xx 24 Civil Engineering Corps 5100 20 ATC 72xx 10 O.R./Sys Analysis 49/57xx 4 Spec. Duty 88xx 2 Spec. War LDO 6152 1 Avn . Acquisitions 80xx 1...6290 1 Avn . Maint. LDO 6330 6 Air Traffic Control LDO 6390 1 Admin LDO 6410 5 IS LDO 6420 2 Met/Ocean LDO 6460 1 467 294 502 Ground Combat Support 1304

An Enterprise-Wide Model for Redistributing Excess Material

DTIC Science & Technology

2012-12-01

107,207,236.82 BLANK $2,047,184.25 $2,108,998.49 $2,328,683.08 $2,328,683.08 $2,811,032.68 AVN $1,749,973.25 $1,875,310.61 $2,009,566.99...SOUTHWEST $10,332,842.03 $8,142,023.44 $8,790,981.90 $8,790,981.90 $9,537,152.92 AVN $1,134,389.58 $1,036,453.46 $1,133,249.27 $1,133,249.27 $125,192.90...1,638,635.04 $1,722,803.38 $2,172,371.60 $2,172,371.60 $1,921,743.69 AVN $8,993.33 $6,622.32 $97,857.13 $97,857.13 $7,798.45 MARINES $541.34 $5,597.11

In vivo and in vitro characteristic of HIF-1α and relative genes in ischemic femoral head necrosis

PubMed Central

Zhang, Wanglin; Yuan, Zhe; Pei, Xinhong; Ma, Ruixue

2015-01-01

Background: Legg-Calvé-Perthes Disease (Perthes’ disease) is a childhood hip disorder initiated by ischemic necrosis of the growing femoral head. So far, the etiology and pathogenesis of Perthes’ disease is poorly understood. Materials and methods: Avascular osteonecrosis rat model was established to mimic the pathophysiological changes of femoral head necrosis. The chondrocytes of newborn Sprague-Dawley rats were isolated and cultured in hypoxic and normoxic condition. The expression characteristic of the hypoxia-inducible factor-1 alpha (HIF-1α) was evaluated both in vivo and in vitro models. Vascular endothelial growth factor (VEGF) and apoptotic genes in chondrocytes treated with normoxia and hypoxia were also studied. Results: HIF-1α expression increased greatly after ischemic operation and kept at relative high level in the arthromeningitis stage and declined in the stages of osteonecrosis and reconstruction. The HIF-1α mRNA levels of chondrocytes incubated at hypoxia were significantly higher than the cells treated with normoxia at 24 and 72 hours. Hypoxia inhibited VEGF expression; chondrocytes could oppose this inhibition manifested by the increasing of VEGF mRNA level after 72 hours hypoxia. The expression of apoptotic genes, Casp3, Casp8 and Casp9, elevated in chondrocytes after hypoxia with time differences. Conclusion: Hypoxia might be an etiological factor for femoral head necrosis, HIF-1α, VEGF as well as apoptotic genes participated the pathophysiological process of ischemic osteonecrosis. PMID:26261616

Long-term Outcome of Multiple Small-diameter Drilling Decompression Combined with Hip Arthroscopy versus Drilling Alone for Early Avascular Necrosis of the Femoral Head.

PubMed

Li, Ji; Li, Zhong-Li; Zhang, Hao; Su, Xiang-Zheng; Wang, Ke-Tao; Yang, Yi-Meng

2017-06-20

Avascular necrosis of femoral head (AVNFH) typically presents in the young adults and progresses quickly without proper treatments. However, the optimum treatments for early stage of AVNFH are still controversial. This study was conducted to evaluate the therapeutic effects of multiple small-diameter drilling decompression combined with hip arthroscopy for early AVNFH compared to drilling alone. This is a nonrandomized retrospective case series study. Between April 2006 and November 2010, 60 patients (98 hips) with early stage AVNFH participated in this study. The patients underwent multiple small-diameter drilling decompression combined with hip arthroscopy in 26 cases/43 hips (Group A) or drilling decompression alone in 34 cases/55 hips (Group B). Patients were followed up at 6, 12, and 24 weeks, and every 6 months thereafter. Radiographs were taken at every follow-up, Harris scores were recorded at the last follow-up, the paired t-test was used to compare the postoperative Harris scores. Surgery effective rate of the two groups was compared using the Chi-square test. All patients were followed up for an average of 57.6 months (range: 17-108 months). Pain relief and improvement of hip function were assessed in all patients at 6 months after the surgery. At the last follow-up, Group A had better outcome with mean Harris' scores improved from 68.23 ± 11.37 to 82.07 ± 2.92 (t = -7.21, P = 0.001) than Group B with mean Harris' scores improved from 69.46 ± 9.71 to 75.79 ± 4.13 (t = -9.47, P = 0.037) (significantly different: t = -2.54, P = 0.017). The total surgery effective rate was also significantly different between Groups A and B (86.0% vs. 74.5%; χ2 = 3.69, P = 0.02). For early stage of AVNFH, multiple small-diameter drilling decompression combined with hip arthroscopy is more effective than drilling decompression alone.

Incidence of Avascular Necrosis of the Femoral Head After Intramedullary Nailing of Femoral Shaft Fractures

PubMed Central

Kim, Ji Wan; Oh, Jong-Keon; Byun, Young-Soo; Shon, Oog-Jin; Park, Jai Hyung; Oh, Hyoung Keun; Shon, Hyun Chul; Park, Ki Chul; Kim, Jung Jae; Lim, Seung-Jae

2016-01-01

Abstract The goal of this study was to determine the incidence of avascular necrosis of the femoral head (AVNFH) after intramedullary nailing of femoral shaft fractures and to identify risk factors for developing AVNFH. We retrospectively reviewed all patients with femoral shaft fractures treated with antegrade intramedullary nailing at 10 institutions. Among the 703 patients enrolled, 161 patients were excluded leaving 542 patients in the study. Average age was 42.1 years with average follow-up of 26.3 months. Patient characteristics and fracture patterns as well as entry point of femoral nails were identified and the incidence of AVNFH was investigated. Patients were divided into 2 groups according to open versus closed physis, open versus closed fractures, and age (<20 versus ≥20 years). Overall incidence of AVNFH was 0.2% (1 of 542): the patient was 15-year-old boy. Of 25 patients with open physis, the incidence of AVNFH was 4%, whereas none of 517 patients with closed physis developed AVNFH (P < 0.001). The incidence of AVNFH in patients aged < 20 versus ≥20 years was 1.1% (1 of 93) and 0.0% (0 of 449), respectively (P = 0.172), which meant that the incidence of AVNFH was 0% in adult with femur shaft fracture. Of 61 patients with open fractures, the incidence of AVNFH was 0%. The number of cases with entry point at the trochanteric fossa or tip of the greater trochanter (GT) was 324 and 218, respectively, and the incidence of AVNFH was 0.3% and 0.0%, respectively (P = 0.412). In patients aged ≥20 years with isolated femoral shaft fracture, there was no case of AVNFH following antegrade intramedullary nailing regardless of the entry point. Therefore, our findings suggest that the risk of AVNFH following antegrade femoral nailing is extremely low in adult patients. PMID:26844518

Protocol for a randomised control trial of bisphosphonate (zoledronic acid) treatment in childhood femoral head avascular necrosis due to Perthes disease

PubMed Central

Zacharin, Margaret; Foster, Bruce; Donald, Geoffrey; Hassall, Timothy; Siafarikas, Aris; Johnson, Michael; Tham, Elaine; Whitewood, Colin; Gebski, Val; Cowell, Chris T; Little, David Graham; Munns, Craig Frank

2017-01-01

Introduction Perthes disease (PD) is an idiopathic disorder presenting with avascular necrosis to the femoral head, which frequently results in flattening. Long-term function is directly related to the subsequent femoral head sphericity. Current treatment includes mechanical modalities and surgical procedures, which are therapeutic but are not uniformly able to prevent collapse. The use of the nitrogen-containing bisphosphonate zoledronic acid (ZA) to inhibit osteoclastic bone resorption is aimed at preserving femoral head strength, reducing collapse and thus maintaining shape. The proposed multicentre, prospective, randomised controlled trial intends to evaluate the efficacy of ZA treatment in PD. Methods and analysis An open-label randomised control trial recruiting 100 children (50 each treatment arm) 5 to 16 years old with unilateral PD. Subjects are randomly assigned to either (a) ZA and standard care or (b) Standard care. The primary outcome measure is deformity index (DI), a radiographic parameter of femoral head roundness assessed at 24 months, following 12 months of ZA treatment (3-monthly doses of ZA 0.025 mg/kg at baseline, 3, 6, 9 and 12 months) plus 12 months observation (group A) or 24 months of observation (group B). Secondary outcome measures are femoral head subluxation, Faces Pain scale, Harris hip score and quality of life. Assessments are made at baseline, 3 monthly during the first year of follow-up and then 6 monthly, until the 24th month. Ethics and dissemination The study commenced following the written approval from the Human Research Ethics Committee. Safety considerations regarding the effects of ZA are monitored which include the subject’s symptomatology, mineral status, bone mass and turnover activity, and metaphyseal modelling. Data handling plan requires that all documents, clinical information, biological samples and investigation results will be held in strict confidence by study investigators to preserve its safety and confidentiality. Trial registration number Australian and New Zealand Clinical Trials ACTRN12610000407099, pre-results. PMID:29637122

A novel p. Gly630Ser mutation of COL2A1 in a Chinese family with presentations of Legg-Calvé-Perthes disease or avascular necrosis of the femoral head.

PubMed

Li, Na; Yu, Jian; Cao, Xiang; Wu, Qiu-Yue; Li, Wei-Wei; Li, Tian-Fu; Zhang, Cui; Cui, Ying-Xia; Li, Xiao-Jun; Yin, Zhi-Min; Xia, Xin-Yi

2014-01-01

Mutations in the type II collagen gene are associated with certain human disorders, collectively termed type II collagenopathies. They include Legg-Calvé-Perthes disease (LCPD) and avascular necrosis of the femoral head (ANFH). These two diseases are skeletal dysplasias, inherited in an autosomal dominant fashion, characterized by groin pain, dislocation of the hip and diminished joint mobility. Coxa vara and elevation of the greater trochanter of the femur comprise the typical phenotype of LCPD, but do not occur in ANFH. Lack of synthesis of type II collagen and structural defects are responsible for the major clinical outcomes, because collagen is the essential matrix protein of all connective tissues. Type II collagen, encoded by the COL2A1 gene, contains N- and C- terminal regions that are cleaved after secretion into the extracellular matrix, and the core area is composed of a triple helical (Gly-X-Y) domain. If the Gly in this specific region is replaced by other amino acids, the structure of type II collagen will be destroyed. Forty-five members of a four-generation family were recruited and investigated. Diagnosis was made by independent orthopedic surgeons and radiologists. A mutation of the COL2A1 gene was detected. In our research, we identify a heterozygous mutation (c.1888 G>A, p. Gly630Ser) in exon 29 of COL2A1 in the Gly-X-Y domain, in a Chinese family affected by LCPD and ANFH. Our findings provide significant clues to the phenotype-genotype relationships in these syndromes and may be helpful in clinical diagnosis. Furthermore, these results should assist further studies of the mechanisms underlying collagen diseases. Our data add new variants to the repertoire of COL2A1 mutation resulting in related collagenopathies.

Multiple drilling compared with standard core decompression for avascular necrosis of the femoral head in sickle cell disease patients.

PubMed

Al Omran, Abdullah

2013-05-01

Sickle cell disease (SCD) is the most common cause of avascular necrosis of femoral head (ANFH) in childhood. Advances in medical treatment led to improved life expectancy of such patients. SCD-related ANFH frequently progress to total collapse of the femoral head necessitating hip replacement. However, SCD patient are at more risk of intra- and post-operative complications and suboptimal outcome of total hip arthroplasty. Hence, it is imperative to preserve the femoral head as long as possible. Between September 1992 and June 2007, 94 core decompression procedures were done to SCD patients who had modified Ficat stage I, IIA and IIB ANFH. Sixty one patients underwent a classical 8-mm drilling and 33 patients underwent 3.2-mm diameter MD technique. Patients were followed up for minimum of 2 years and were evaluated for clinical and Harris Hip Score improvement and for radiological progression. All 19 hips that had Ficat stage I had significant reduction of pain and improvement of Harris Hip Score. No patient has required further surgery. Among the 39 hips with Ficat IIA at time of procedure, 80 % of hips which underwent CD and 78 % of MD cases had significant reduction of pain and improvement of HHS. Those patients showed no radiographic progression of the disease. The remaining, 20 % CD and 22 % MD eventually progressed radiologically to grade III or grade IV and had HHS less than 75 at last visit. In the 36 cases with Ficat IIB, 52 % CD and 52.8 % MC had significant reduction of pain and improvement of HHS. The rest showed no improvement in pain and function, and progressed to stage IV; 11 of them underwent THA and one patient refused surgery. While multiple drilling is safer and less invasive than single coring in SCD, there is no statistically significant difference in outcome or complication rate between both procedures done for ANFH in patients with SCD.

Patterns of premature physeal arrest: MR imaging of 111 children.

PubMed

Ecklund, Kirsten; Jaramillo, Diego

2002-04-01

The purpose of this study was to use MR imaging, especially fat-suppressed three-dimensional (3D) spoiled gradient-recalled echo sequences, to identify patterns of growth arrest after physeal insult in children. We evaluated 111 children with physeal bone bridges (median age, 11.4 years) using MR imaging to analyze bridge size, location in physis, signal intensity, growth recovery lines, avascular necrosis, and metaphyseal cartilage tongues. Fifty-eight patients underwent fat-suppressed 3D spoiled gradient-recalled echo imaging with physeal mapping. The cause, bone involved, radiographic appearance, and surgical interventions (60/111) were also correlated. Data were analyzed with the two-tailed Fisher's exact test. Posttraumatic bridges, accounting for 70% (78/111) of patients, were most often distal, especially of the tibia (n = 43) and femur (n = 14), whereas those due to the other miscellaneous causes were more frequently proximal (p < 0.0001). The position of the bridge in the physis was related to the bone involved (p < 0.0001). Sixty-five percent of distal tibial bridges involved the anteromedial physis, whereas 60% of the distal femoral arrests were central. Larger bridges had higher T1 signal intensity (p < 0.008). Oblique growth recovery lines were seen exclusively with bridges involving the peripheral physis (p = 0.002) and smaller, more potentially resectable bridges. Metaphyseal cartilaginous tongues were seen with all causes, but avascular necrosis was exclusively posttraumatic (p = 0.03). Signal characteristics and bridge size did not vary with the cause. Premature physeal bony bridging in children is most often posttraumatic and disproportionately involves the distal tibia and femur where bridges tend to develop at the sites of earliest physiologic closure, namely anteromedially and centrally, respectively. MR imaging, especially with the use of fat-suppressed 3D spoiled gradient-recalled echo imaging, exquisitely shows the growth disturbance and associated abnormalities that may follow physeal injury and guides surgical management.

Born Lucky: The Institutional Sources behind the Third United States Army Headquarters’ Procedures in Northwest Europe, 1944-45

DTIC Science & Technology

2014-05-22

Engineer Bn., Co. B, 942nd Engineer Avn . Bn., Third US Army, 1 August 1944- 9 May 1945: Vol. I, The Operations, After Action Report (Germany...practitioners are willing to investigate the possibilities. 69 BIBLIOGRAPHY 652nd Engineer Bn., Co. B, 942nd Engineer Avn . Bn. Third US Army, 1 August

Balancing Agile Combat Support Manpower to Better Meet the Future Security Environment

DTIC Science & Technology

2014-01-01

for a 3,000-person deployment package. 6 Figure 1.1 Postured Manpower Included in This Analysis NOTE: Spc = space, Avn = aviation, MX...an po w er ,  1 00 0s USAF  postured  manpower Spc,   Avn ,  Mx,  Intel Other  ACS Our  scope 7 • In Chapter Four, we discuss several

Assessing Conventional Army Demands and Requirements for Ultra-Light Tactical Mobility

DTIC Science & Technology

2015-01-01

hour Enemy or adversary actions Population Decision points Reserve Fires Engineer PMO AMD CBRN Intelligence R&S Avn Bde M o ve m en t an d m an eu ve...LDMove on Route Irish Seize on OBJ Irene 2nd BCT Cross LDMove on Route Longstreet Seize on OBJ Rose 3rd BCT FPOL with 1st BCT Airdrop resupply AMD Avn Bde

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cabello, Adan

We introduce two two-player quantum pseudotelepathy games based on two recently proposed all-versus-nothing (AVN) proofs of Bell's theorem [A. Cabello, Phys. Rev. Lett. 95, 210401 (2005); Phys. Rev. A 72, 050101(R) (2005)]. These games prove that Broadbent and Methot's claim that these AVN proofs do not rule out local-hidden-variable theories in which it is possible to exchange unlimited information inside the same light cone (quant-ph/0511047) is incorrect.

Wilma Historical Page - Office of Satellite and Product Operations

Science.gov Websites

» Disclaimer » Web Linking Policy » Use of Data and Products » FAQs: Imagery Contact Us Services Argos DCS Report and Advisory Archive. Floater Imagery October 24/0715Z to 24/1415Z: Image: AVN | BD | FT | IR | IR2 | JSL | RB | RGB | VIS | WV Image (w/ Latitude & Longitude): AVN | BD | FT | IR | IR2 | JSL

Rita Historical Page - Office of Satellite and Product Operations

Science.gov Websites

» Disclaimer » Web Linking Policy » Use of Data and Products » FAQs: Imagery Contact Us Services Argos DCS Advisory Archive. Floater Imagery September 24/0015Z to 24/1345Z: Image: AVN | BD | FT | IR | IR2 | JSL | RB | RGB | VIS | WV Image (w/ Latitude & Longitude): AVN | BD | FT | IR | IR2 | JSL | RB | RGB

The Antivascular Actions of Mild Intensity Ultrasound on a Murine Neoplasm

NASA Astrophysics Data System (ADS)

Wood, Andrew K. W.; Bunte, Ralph M.; Ansaloni, Sara; Lee, William M.-F.; Sehgal, Chandra M.

2006-05-01

This study was aimed at determining whether mild intensity ultrasound affected the fragile and leaky angiogenic blood vessels in a tumor. In 27 mice (C3HV/HeN strain) a subcutaneous melanoma (K173522) was insonated with continuous physiotherapy ultrasound (1 MHz; spatial-average-temporal-average = 2.3 W cm-2). Analyses of contrast enhanced power Doppler observations showed that insonation significantly increased the avascular area in the neoplasm. A linear regression analysis demonstrated that each min of insonation lead to a 25% reduction in tumor vascularity. The predominant acute effect of insonation was an apparently irreparable dilation of the tumor capillaries; liquefactive necrosis of neoplastic cells, related to a secondary ischemia, was a delayed effect.

Percutaneous Cementoplasty for Kienbock's Disease.

PubMed

Vallejo, Eduardo Crespo; Martinez-Galdámez, Mario; Martin, Ernesto Santos; de Gregorio, Arturo Perera; Gallego, Miriam Gamo; Escobar, Angeles Ramirez

2017-05-01

Kienböck disease typically presents with wrist pain, swelling, restricted range of motion, and difficulty in performing activities of daily living. Because the etiology and evolution of disease remain unclear, broad ranges of treatments have been designed. Percutaneous cementoplasty is expanding its role for managing painful bone metastases outside the spine. We can draw a parallel between lytic tumoral lesions and Kienbock's disease. Increasing the strength and rigidity of lunate with cementoplasty can prevent it from collapse, relieve the symptoms associated with the process of avascular necrosis, and increase the wrist range of motion. We report the case of 30-year-old man with a painful stage IIIA Kienböck disease who underwent percutaneous cementoplasty and experienced immediate effective pain relief and recovery of wrist mobility.

Delayed fixation of displaced bilateral, atraumatic, femoral neck fractures in a patient with pregnancy related osteomalacia.

PubMed

Docker, Charles; Starks, Ian; Wade, Roger; Wynn-Jones, Charles

2011-06-01

We present the case of a woman diagnosed with simultaneous displaced intracapsular femoral neck fractures following the birth of her second child. No traumatic event was identified. Diagnosis was delayed as the cause of her pain was thought to be non-skeletal in origin. Radiological and serological investigations were diagnostic of osteomalacia. Surgical fixation of her fractures was further delayed due to profound hypocalcaemia. Despite the delays, fixation with bilateral dynamic hip screws resulted in union with no evidence of avascular necrosis at 2 years follow-up. We believe this to be the first report of atraumatic bilateral femoral neck fractures and it shows that a good result can be achieved even in the presence of delayed fixation.

Identification and therapeutic potential of a vitronectin binding region of meningococcal msf.

PubMed

Hill, Darryl J; Griffiths, Natalie J; Borodina, Elena; Andreae, Clio A; Sessions, Richard B; Virji, Mumtaz

2015-01-01

The human pathogen Neisseria meningitides (Nm) attains serum resistance via a number of mechanisms, one of which involves binding to the host complement regulator protein vitronectin. We have shown previously that the Meningococcal surface fibril (Msf), a trimeric autotransporter, binds to the activated form of vitronectin (aVn) to increase Nm survival in human serum. In this study, we aimed to identify the aVn-binding region of Msf to assess its potential as an antigen which can elicit antibodies that block aVn binding and/or possess bactericidal properties. Using several recombinant Msf fragments spanning its surface-exposed region, the smallest aVn-binding recombinants were found to span residues 1-86 and 39-124. The use of further deletion constructs and overlapping recombinant Msf fragments suggested that a region of Msf comprising residues 39-82 may be primarily important for aVn binding and that other regions may also be involved but to a lesser extent. Molecular modelling implicated K66 and K68, conserved in all available Msf sequences, to be involved in the interaction. Recombinant fragments which bound to aVn were able to reduce the survival advantage conveyed by aVn-interaction in serum bactericidal assays. Antibodies raised against one such fragment inhibited aVn binding to Msf. In addition, the antibodies enhanced specific killing of Msf-expressing Nm in a dose-dependent manner. Overall, this study identifies an aVn-binding region of Msf, an adhesin known to impart serum resistance properties to the pathogen; and shows that this region of Msf can elicit antibodies with dual properties which reduce pathogen survival within the host and thus has potential as a vaccine antigen.

AVN-322 is a Safe Orally Bio-Available Potent and Highly Selective Antagonist of 5-HT6R with Demonstrated Ability to Improve Impaired Memory in Animal Models.

PubMed

Ivachtchenko, Alexandre V; Ivanenkov, Yan A; Veselov, Mark S; Okun, I M

2017-01-01

In recent years, 5-hydroxytryptamine subtype 6 receptor (5-HT6 receptor, 5- HT6R) has emerged as a promising therapeutic target for the treatment of neuropathological disorders, including Alzheimer's disease (AD) and schizophrenia. 5-HT6 receptors were hypothesized to be implicated in the processes of learning, memory, and cognition with 5-HT6R antagonists being effective in animal models of cognition and memory impairment. Several selective 5-HT6R ligands are currently undergoing clinical trials for treatment of AD. We describe results of preclinical development of a novel and highly selective and potent 5- HT6R antagonist, AVN-322, as a clinical candidate for the treatment of AD to improve concurrent debilitation of memory and cognition in the AD patients, and schizophrenia as a substance with antipsychotic effect. In the manuscript, we present its in vitro and vivo efficacy, ADME, pharmacokinetics in animals and in humans, and toxicity. While having high binding affinity in medium picomolar range, the lead compound demonstrates substantially better selectivity index then the reference drug candidates currently being tested in clinical studies. AVN-322 showed high oral bioavailability and favorable blood-brain barrier (BBB) penetration. In vivo testing revealed its clear cognition enhancing effect. AVN-322 significantly restored both scopolamine- and MK-801-induced cognitive dysfunction and demonstrated antipsychotic potential. Taking into account its good safety profile and favorable pharmacokinetics, AVN-322 can be reasonably considered as a novel drug candidate for the treatment of neurological disorders such as AD and/or schizophrenia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Altered profile of mRNA expression in atrioventricular node of streptozotocin-induced diabetic rats

PubMed Central

Howarth, Frank Christopher; Parekh, Khatija; Jayaprakash, Petrilla; Inbaraj, Edward Samuel; Oz, Murat; Dobrzynski, Halina; Adrian, Thomas Edward

2017-01-01

Prolonged action potential duration, reduced action potential firing rate, upstroke velocity and rate of diastolic depolarization have been demonstrated in atrioventricular node (AVN) cells from streptozotocin (STZ)-induced diabetic rats. To further clarify the molecular basis of these electrical disturbances, the mRNA profiles encoding a variety of proteins associated with the generation and conduction of electrical activity in the AVN, were evaluated in the STZ-induced diabetic rat heart. Expression of mRNA was measured in AVN biopsies using reverse transcription-quantitative polymerase chain reaction techniques. Notable differences in mRNA expression included upregulation of genes encoding membrane and intracellular Ca2+ transport, including solute carrier family 8 member A1, transient receptor potential channel 1, ryanodine receptor 2/3, hyperpolarization-activated cyclic-nucleotide 2 and 3, calcium channel voltage-dependent, β2 subunit and sodium channels 3a, 4a, 7a and 3b. In addition to this, potassium channels potassium voltage-gated channel subfamily A member 4, potassium channel calcium activated intermediate/small conductance subfamily N α member 2, potassium voltage-gated channel subfamily J members 3, 5, and 11, potassium channel subfamily K members 1, 2, 3 and natriuretic peptide B (BNP) were upregulated in AVN of STZ heart, compared with controls. Alterations in gene expression were associated with upregulation of various proteins including the inwardly rectifying, potassium channel Kir3.4, NCX1 and BNP. The present study demonstrated notable differences in the profile of mRNA encoding proteins associated with the generation, conduction and regulation of electrical signals in the AVN of the STZ-induced diabetic rat heart. These data will provide a basis for a substantial range of future studies to investigate whether variations in mRNA translate into alterations in electrophysiological function. PMID:28731153

Identification and Therapeutic Potential of a Vitronectin Binding Region of Meningococcal Msf

PubMed Central

Hill, Darryl J.; Griffiths, Natalie J.; Borodina, Elena; Andreae, Clio A.; Sessions, Richard B.; Virji, Mumtaz

2015-01-01

The human pathogen Neisseria meningitides (Nm) attains serum resistance via a number of mechanisms, one of which involves binding to the host complement regulator protein vitronectin. We have shown previously that the Meningococcal surface fibril (Msf), a trimeric autotransporter, binds to the activated form of vitronectin (aVn) to increase Nm survival in human serum. In this study, we aimed to identify the aVn-binding region of Msf to assess its potential as an antigen which can elicit antibodies that block aVn binding and/or possess bactericidal properties. Using several recombinant Msf fragments spanning its surface-exposed region, the smallest aVn-binding recombinants were found to span residues 1-86 and 39-124. The use of further deletion constructs and overlapping recombinant Msf fragments suggested that a region of Msf comprising residues 39-82 may be primarily important for aVn binding and that other regions may also be involved but to a lesser extent. Molecular modelling implicated K66 and K68, conserved in all available Msf sequences, to be involved in the interaction. Recombinant fragments which bound to aVn were able to reduce the survival advantage conveyed by aVn-interaction in serum bactericidal assays. Antibodies raised against one such fragment inhibited aVn binding to Msf. In addition, the antibodies enhanced specific killing of Msf-expressing Nm in a dose-dependent manner. Overall, this study identifies an aVn-binding region of Msf, an adhesin known to impart serum resistance properties to the pathogen; and shows that this region of Msf can elicit antibodies with dual properties which reduce pathogen survival within the host and thus has potential as a vaccine antigen. PMID:25826209

U.S. Army Aeromedical Research Laboratory Annual Progress Report Fiscal Year 2011

DTIC Science & Technology

2012-06-01

Manager Mr. J. Miller 6811 Avn Std Officer Mr. J. Ramiccio 6957 Library………………..6936 Manpower…………...6840 MARS Facility……….6990 S-1 .......………………6886 Visual...Services Blood Program (ASBP) blood drive, sponsored by Lyster Army Health Clinic and the 1-13th AVN RGT. A USAARL civilian employee is a

Some implications of Scale Relativity theory in avascular stages of growth of solid tumors in the presence of an immune system response.

PubMed

Buzea, C Gh; Agop, M; Moraru, Evelina; Stana, Bogdan A; Gîrţu, Manuela; Iancu, D

2011-08-07

We present a traveling-wave analysis of a reduced mathematical model describing the growth of a solid tumor in the presence of an immune system response in the framework of Scale Relativity theory. Attention is focused upon the attack of tumor cells by tumor-infiltrating cytotoxic lymphocytes (TICLs), in a small multicellular tumor, without necrosis and at some stage prior to (tumor-induced) angiogenesis. For a particular choice of parameters, the underlying system of partial differential equations is able to simulate the well-documented phenomenon of cancer dormancy and propagation of a perturbation in the tumor cell concentration by cnoidal modes, by depicting spatially heterogeneous tumor cell distributions that are characterized by a relatively small total number of tumor cells. This behavior is consistent with several immunomorphological investigations. Moreover, the alteration of certain parameters of the model is enough to induce soliton like modes and soliton packets into the system, which in turn result in tumor invasion in the form of a standard traveling wave. In the same framework of Scale Relativity theory, a very important feature of malignant tumors also results, that even in avascular stages they might propagate and invade healthy tissues, by means of a diffusion on a Newtonian fluid. Copyright © 2011 Elsevier Ltd. All rights reserved.

Live, Virtual, and Constructive-Training Environment: A Vision and Strategy for the Marine Corps

DTIC Science & Technology

2014-09-01

Research Lab ATF&PD Advocacy, Transition, Fiscal and Personnel, Budget, Operations Division ATS Aviation Training Systems AVN Aviation BFT Blue...MEFs DC, CD&I MARFORs MEFs DCs HQMC Reps ACMC DC, CD&I DC, P&R DC, PP&O DC, I&L DC,  AVN Community forum to  identify and prioritize  issues Review Trng M

Optimizing the African VLBI Network for Astronomy and Geodesy

NASA Astrophysics Data System (ADS)

de Witt, A.; Mayer, D.; MacLeod, G.; Combrinck, L.; Petrov, L.; Nickola, M.

2016-12-01

The African VLBI Network will be a pan-African network of radio telescopes comprised of converted redundant satellite Earth-station antennas and new purpose-built radio telescopes. The first of these antennas, in Ghana, is currently being converted to a radio telescope and current funding is estimated to permit the conversion of two more antennas in Africa. These antennas will initially be equipped with a 5-GHz and 6.7-GHz receiver and the next receiver likely to be fitted is a 1.4-1.7-GHz receiver. While it would be advantageous for the AVN antennas to be able to participate also in geodetic and astrometric VLBI observations, there is no funding currently for this. In this paper we re-visit the scientific justifications for the AVN in an attempt to optimize the AVN for each science case, both astronomical and geodetic.

The African VLBI network project

NASA Astrophysics Data System (ADS)

Loots, Anita

2015-01-01

The AVN is one of the most significant vehicles through which capacity development in Africa for SKA participation will be realized. It is a forerunner to the long baseline Phase 2 component of the mid-frequency SKA. Besides the 26m HartRAO telescope in South Africa, Ghana is expected to be the first to establish a VLBI-capable telescope through conversion of a redundant 32m telecommunications system near Accra. The most widely used receivers in the EVN are L-band and C-band (5 GHz). L-band is divided into a low band around the hydrogen (HI) line frequency of 1420 MHz, and a high band covering the hydroxyl line frequencies of 1612-1720 MHz. The high band is much more commonly used for VLBI as it provides more bandwidth. For the AVN, the methanol maser line at 6668 MHz is a key target for the initial receiver and the related 12178MHz methanol maser line also seen in star-forming regions a potential future Ku-band receiver. In the potential future band around 22GHz(K-band), water masers in star-forming regions and meg-maser galaxies at 22.235 GHz are targets, as are other radio continuum sources such as AGNs. The AVN system will include 5GHz and 6.668GHz receiver systems with recommendation to partner countries that the first upgrade should be L-band receivers. The original satellite telecommunications feed horns cover 3.8 - 6.4 GHz and should work at 5 GHz and operation at 6.668 GHz for the methanol maser is yet to be verified. The first light science will be conducted in the 6.7 GHz methanol maser band. Telescopes developed for the AVN will initially join other global networks for VLBI. When at least four VLBI-capable telescopes are operational on the continent, it will be possible to initiate stand-alone AVN VLBI. Each country where an AVN telescope becomes operational will have its own single-dish observing program. Capacity building to run an observatory includes the establishment of competent core essential observatory staff in partner countries who can train larger teams in science, engineering and technology issues and collaborate with the broader global science community to develop new African radio astronomy science communities.

SU-C-303-06: Treatment Planning Study for Non-Invasive Cardiac Arrhythmia Ablation with Scanned Carbon Ions in An Animal Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eichhorn, A; Constantinescu, A; Prall, M

Purpose: Scanned carbon ion beams might offer a non-invasive alternative treatment for cardiac arrhythmia, which are a major health-burden. We studied the feasibility of this procedure in an animal model. The underlying treatment planning and motion mitigation strategies will be presented. Methods: The study was carried out in 15 pigs, randomly distributed to 3 target groups: atrioventricular node (AVN, 8 animals with 25, 40, and 55 Gy target dose), left ventricular free-wall (LV, 4 animals with 40 Gy) and superior pulmonary vein (SPV, 3 animals with 40 Gy). Breathing motion was suppressed by repeated enforced breathholds at end exhale. Cardiacmore » motion was mitigated by an inhomogeneous rescanning scheme with up to 15 rescans. The treatment planning was performed using the GSI in-house software TRiP4D on cardiac-gated 4DCTs, applying a range-considering ITV based on an extended CTV. For AVN and SPV isotropic 5 mm margins were applied to the CTV, while for the LV 2mm+2% range margins were used. The opposing fields for AVN and LV targets were optimized independently (SFUD), while SPV treatments were optimized as IMPT deliveries, including dose restrictions to the radiosensitive AVN. Results: Median value of D{sub 95} over all rescanning simulations was 99.1% (AVN), 98.0% (SPV) and 98.3% (LV) for the CTV and 94.7% (AVN) and 92.7% (SPV) for the PTV, respectively. The median D{sub 5}-D{sub 95} was improved with rescanning compared to unmitigated delivery from 13.3 to 6.5% (CTV) and from 23.4 to 11.6% (PTV). ICRP dose limits for aorta, trachea, esophagus and skin were respected. The maximal dose in the coronary arteries was limited to 30 Gy. Conclusion: We demonstrated the feasibility of a homogeneous dose delivery to different cardiac structures in a porcine model using a time-optimized inhomogeneous rescanning scheme. The presented treatment planning strategies were applied in a pig study with the analysis ongoing. Funding: This work was supported in part by the Helmholtz Association, the American Heart Association Midwest Affiliate Postdoctoral Fellowship Grant, the Mayo Clinic Foundation, and the Goldsmith Foundation.« less

Percutaneous Cementoplasty for Kienbock’s Disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vallejo, Eduardo Crespo, E-mail: dreduardocrespo@gmail.com; Martinez-Galdámez, Mario; Martin, Ernesto Santos

Kienböck disease typically presents with wrist pain, swelling, restricted range of motion, and difficulty in performing activities of daily living. Because the etiology and evolution of disease remain unclear, broad ranges of treatments have been designed. Percutaneous cementoplasty is expanding its role for managing painful bone metastases outside the spine. We can draw a parallel between lytic tumoral lesions and Kienbock’s disease. Increasing the strength and rigidity of lunate with cementoplasty can prevent it from collapse, relieve the symptoms associated with the process of avascular necrosis, and increase the wrist range of motion. We report the case of 30-year-old manmore » with a painful stage IIIA Kienböck disease who underwent percutaneous cementoplasty and experienced immediate effective pain relief and recovery of wrist mobility.« less

Generation of clinical grade human bone marrow stromal cells for use in bone regeneration

PubMed Central

Robey, Pamela G.; Kuznetsov, Sergei A.; Ren, Jiaqiang; Klein, Harvey G.; Sabatino, Marianna; Stroncek, David F.

2014-01-01

In current orthopaedic practice, there is a need to increase the ability to reconstruct large segments of bone lost due to trauma, resection of tumors and skeletal deformities, or when normal regenerative processes have failed such as in non-unions and avascular necrosis. Bone marrow stromal cells (BMSCs, also known as bone marrow-derived mesenchymal stem cells), when used in conjunction with appropriate carriers, represent a means by which to achieve bone regeneration in such cases. While much has been done at the bench and in pre-clinical studies, moving towards clinical application requires the generation of clinical grade cells. What is described herein is an FDA-approved cell manufacturing procedure for the ex vivo expansion of high quality, biologically active human BMSCs. PMID:25064527

Vascularized bone graft for scaphoid nonunions.

PubMed

Mih, Alexander D

2004-09-01

Scaphoid fracture nonunion remains a challenging problem that may persist despite traditional methods of bone grafting and internal fixation. The alteration of wrist mechanics created by nonunion as well as the development of avascular necrosis leads to degenerative change of the radiocarpal joint accompanied by loss of motion and pain. The use of a vascularized bone graft has the theoretical benefit of increased blood flow that exceeds that of nonvascularized grafts. Numerous sources of vascularized bone graft have been described, including those from remote sites as well as from the carpus and distal radius. Knowledge of the blood supply to the distal radius has allowed for development of several vascularized bone graft harvest sites. The results of vascularized bone grafting from the distal radius have been encouraging, with numerous authors reporting the successful treatment of scaphoid nonunions.

[Professor Shi Qi's experience of applying herbal paste for treating chronic musculoskeletal conditions].

PubMed

Li, Xiao-feng; Wang, Yong-jun; Ye, Xiu-lan; Zhou, Chong-jian

2012-06-01

Professor Shi Qi is a famous traditional Chinese medicine doctor specializing in orthopaedics and traumatology, who has formatted a set of systematic protocols for the diagnosis and treatment of chronic musculoskeletal conditions. When it is time for using tonics in winter, he advocates applying herbal paste for treating chronic musculoskeletal diseases. This paper introduces Professor Shi Qi's commonly used prescription for treating chronic musculoskeletal conditions and puts forward demands and understandings in concocting herbal paste, experience in herbal paste for treating chronic musculoskeletal diseases such as cervical spondylosis, lumbar disc herniation, lumbar spinal stenosis, lumbar muscle strain, ankylosing spondylitis, osteoporosis, knee osteoarthritis and avascular necrosis of femoral head, and the advantages of herbal paste for treating chronic musculoskeletal conditions as opposed to alternative treatments.

[Treatment of adult avascular necrosis of femoral head by transplanting iliac bone flap with deep iliac circumflex vessels and cancellous bone].

PubMed

Yu, Zhiliang; Zhang, Ning; Yang, Yi; Wang, Bin; Gao, Shuo; Zhao, Xiaoyong

2013-07-01

To investigate the effectiveness of transplanting iliac bone flap with deep iliac circumflex vessels and cancellous bone for the treatment of adult avascular necrosis of the femoral head (ANFH). A retrospective analysis was made on the clinical data of 685 patients (803 hips) with ANFH, who underwent iliac bone flap transplantation with deep iliac circumflex vessels and cancellous bone between March 2002 and January 2010. There were 489 males (580 hips) and 196 females (223 hips) with a mean age of 40.4 years (range, 18-63 years), including 567 unilateral cases (303 left hips and 264 right hips) and 118 bilateral cases. The causes of ANFH included alcohol-induced in 223 cases, steroid-induced in 179 cases, alcohol + steroid-induced in 21 cases, traumatic in 136 cases, acetabular dysplasia in 8 cases, bone cyst in 5 cases, septic arthritis in 2 cases, joint tuberculosis in 3 cases, rheumatoid arthritis in 5 cases, and idiopathic in 103 cases. According to Steinberg staging, 211 hips were rated as stage II, 513 hips as stage III, and 79 hips as stage IV. The preoperative Harris hip score was 60.30 +/- 7.02. Fat necrosis occurred in 2 cases after operation, primary healing of incision was obtained in the other cases; delayed infection, lower extremity deep vein thrombosis, and pulmonary embolism occurred in 2 cases, respectively. All patients were followed up 36-60 months (mean, 49 months). Harris hip score at last follow-up (83.50 +/- 7.31) was significantly higher than that at preoperation (t= -2 266.980, P=0.000), and the scores were significantly higher than those at preoperation in different stages (P < 0.05). The results were excellent in 523 hips, good in 185 hips, fair in 65 hips, and poor in 30 hips, and the excellent and good rate was 88.2%. X-ray examination showed bone fusion of transplanted bone flap and bone graft with an average of 4.2 months (range, 3-6 months); according to Steinberg staging, imaging stable rate was 78.3% (629/803) at last follow-up. Iliac bone flap transplantion with deep iliac circumflex vessels and cancellous bone has the advantages of complete decompression of the femoral head, exact flap blood supply, improved blood supply of the femoral head, new support for the femoral head, and participation of osteoinductive effect for the treatment of adult ANFH, so it is an effective treatment for the retention of the femoral head.

Two-player quantum pseudotelepathy based on recent all-versus-nothing violations of local realism

NASA Astrophysics Data System (ADS)

Cabello, Adán

2006-02-01

We introduce two two-player quantum pseudotelepathy games based on two recently proposed all-versus-nothing (AVN) proofs of Bell’s theorem [A. Cabello, Phys. Rev. Lett. 95, 210401 (2005); Phys. Rev. A 72, 050101(R) (2005)]. These games prove that Broadbent and Méthot’s claim that these AVN proofs do not rule out local-hidden-variable theories in which it is possible to exchange unlimited information inside the same light cone (quant-ph/0511047) is incorrect.

Treatment of Aseptic Necrosis of the Lunate Bone (Kienböck Disease) Using a Nickel–Titanium Memory Alloy Arthrodesis Concentrator

PubMed Central

Xu, Yongqing; Li, Chuan; Zhou, Tianhua; Su, Yongyue; He, Xiaoqing; Fan, Xinyu; Zhu, Yueliang

2015-01-01

Abstract Avascular necrosis of the lunate bone (Kienböck disease) is caused by loss of blood supply of the bone. This study aimed to evaluate the efficacy and safety of a novel nickel–titanium (Ni–Ti) memory alloy arthrodesis concentrator in the treatment of this disease. A consecutive 24 patients with stage IIIb aseptic lunate necrosis were treated with scapho-trapezio-trapezoeid (STT) arthrodesis using a Ni–Ti arthrodesis concentrator from August 2008 to December 2012. Wrist pain, grip strength, carpal height, and scapholunate angle were measured and compared before and after the surgery. The wrist functions were evaluated using the Mayo scale. Patients were followed up for a mean of 12 months (range, 6–24 months). Grip strength of the affected side was significantly improved after the surgery (18 ± 4.74 kg vs. 30.21 ± 7.14 kg, P < 0.0001). Wrist pain score was significantly decreased from 5.88 ± 0.9 to 0.5 ± 0.51 (P < 0.0001). Carpal height and Mayo score were also significantly increased after the surgery (P < 0.0001). Scapholunate angle was significantly decreased after the surgery (68.38 ± 7.28° vs. 49.91 ± 4.28°, P < 0.0001). No implant breakage, loose implant, wound infection, or nonunion occurred. STT arthrodesis is effective for the treatment of stage IIIb lunate necrosis. The Ni–Ti memory alloy arthrodesis concentrator is a convenient tool for STT arthrodesis with excellent and reliable results. PMID:26496298

Long-term Outcome of Multiple Small-diameter Drilling Decompression Combined with Hip Arthroscopy versus Drilling Alone for Early Avascular Necrosis of the Femoral Head

PubMed Central

Li, Ji; Li, Zhong-Li; Zhang, Hao; Su, Xiang-Zheng; Wang, Ke-Tao; Yang, Yi-Meng

2017-01-01

Background: Avascular necrosis of femoral head (AVNFH) typically presents in the young adults and progresses quickly without proper treatments. However, the optimum treatments for early stage of AVNFH are still controversial. This study was conducted to evaluate the therapeutic effects of multiple small-diameter drilling decompression combined with hip arthroscopy for early AVNFH compared to drilling alone. Methods: This is a nonrandomized retrospective case series study. Between April 2006 and November 2010, 60 patients (98 hips) with early stage AVNFH participated in this study. The patients underwent multiple small-diameter drilling decompression combined with hip arthroscopy in 26 cases/43 hips (Group A) or drilling decompression alone in 34 cases/55 hips (Group B). Patients were followed up at 6, 12, and 24 weeks, and every 6 months thereafter. Radiographs were taken at every follow-up, Harris scores were recorded at the last follow-up, the paired t-test was used to compare the postoperative Harris scores. Surgery effective rate of the two groups was compared using the Chi-square test. Results: All patients were followed up for an average of 57.6 months (range: 17–108 months). Pain relief and improvement of hip function were assessed in all patients at 6 months after the surgery. At the last follow-up, Group A had better outcome with mean Harris’ scores improved from 68.23 ± 11.37 to 82.07 ± 2.92 (t = −7.21, P = 0.001) than Group B with mean Harris’ scores improved from 69.46 ± 9.71 to 75.79 ± 4.13 (t = –9.47, P = 0.037) (significantly different: t = –2.54, P = 0.017). The total surgery effective rate was also significantly different between Groups A and B (86.0% vs. 74.5%; χ2 = 3.69, P = 0.02). Conclusion: For early stage of AVNFH, multiple small-diameter drilling decompression combined with hip arthroscopy is more effective than drilling decompression alone. PMID:28584206

Upregulation of microRNA-320 decreases the risk of developing steroid-induced avascular necrosis of femoral head by inhibiting CYP1A2 both in vivo and in vitro.

PubMed

Wei, Ji-Hua; Luo, Qun-Qiang; Tang, Yu-Jin; Chen, Ji-Xia; Huang, Chun-Lan; Lu, Ding-Gui; Tang, Qian-Li

2018-06-20

Steroid-induced avascular necrosis of femoral head (SANFH) occurs frequently in patients receiving high-dose steroid treatment for these underlying diseases. The target of this study is to investigate the effect of microRNA-320 (miR-320) on SANFH by targeting CYP1A2. CYP1A2 expression was detected using immunohistochemistry. Specimens were collected from patients with SANFH and femoral neck fracture. Seventy rats were assigned into seven groups. The targeting relationship between miR-320 and CYP1A2 was verified by bioinformatics website and dual luciferase reporter gene assay. RT-qPCR and Western blot analysis were used to detect miR-320 and CYP1A2 expressions. The enzymatic activity of CYP1A2 was detected by fluorescence spectrophotometry. Hemorheology and microcirculation were measured in rats. MiR-320 expression decreased and CYP1A2 expression and enzymatic activity increased in SANFH patients compared to those with femoral neck fracture. CYP1A2 was the target gene of miR-320. Hemorheology and microcirculation results showed that up-regulated expression of CYP1A2 promoted the development of SANFH while increased expression of miR-320 inhibited the development of SANFH. Compared with the SANFH group, the SANFH + miR-320 mimic group showed increased miRNA-320 expression, and decreased CYP1A2 expression and enzymatic activity. Opposite results were found in the SANFH + miR-320 inhibitor group. The SANFH + miR-320 inhibitor + pCR-CYP1A2_KO group showed decreased miRNA-320 expression and the SANFH + pCR-CYP1A2_KO group showed decreased CYP1A2 expression and enzymatic activity. Our findings provide evidences that miR-320 might inhibit the development of SANFH by targeting CYP1A2. Copyright © 2018 Elsevier B.V. All rights reserved.

[Treatment of avascular necrosis of femoral head after femoral neck fracture with pedicled iliac bone graft].

PubMed

Wang, Benjie; Zhao, Dewei; Guo, Lin; Yang, Lei; Li, Zhigang; Cui, Daping; Tian, Fengde; Liu, Baoyi

2011-05-01

To explore the effectiveness of pedicled iliac bone graft transposition for treatment of avascular necrosis of femoral head (ANFH) after femoral neck fracture. Between June 2002 and December 2006, 22 cases (22 hips, 16 left hips and 6 right hips) of ANFH after femoral neck fracture were treated with iliac bone graft pedicled with ascending branch of the lateral femoral circumflex vessels. There were 18 males and 4 females with an age range from 28 to 48 years (mean, 37.5 years). The time from injury to internal fixation was 2-31 days, and all fractures healed within 12 months after internal fixation. The ANFH was diagnosed at 15-40 months (mean, 22 months) after internal fixation. The ANFH duration was 3-11 months (mean, 8 months). According to Association Research Circulation Osseous (ARCO) staging system, 2 hips were classified as stage IIa, 3 hips as stage IIb, 3 hips as stage IIc, 3 hips as stage IIIa, 7 hips as stage IIIb, and 4 hips as stage IIIc. The preoperative Harris hip score (HHS) was 64.10 +/- 5.95. All incisions healed by first intention and the patients had no complication of lung embolism, sciatic nerve injury, lower limb deep venous thrombosis, and numbness and pain of donor site. All patients were followed up 2.5 to 6.3 years (mean, 4.8 years). The fracture healing time was 8-12 months, and no femoral neck fracture recurred. The HHS was 90.20 +/- 5.35 at last follow-up, showing significant difference when compared with the preoperative value (t = -18.447, P = 0.000). The hip function were excellent in 11 hips, good in 10 hips, fair in 1 hip, and the excellent and good rate was 95.5%. Four hips were radiographically progressed in ARCO staging, 18 hips remained stable with a stable rate of 81.8%. Pedicled iliac bone graft transposition is an ideal option for treatment of ANFH after internal fixation of femoral neck fracture for the advantages of femoral head revascularization, sufficient cancellous bone supply, and relatively simple procedure.

Incidence, Risk Factors, and Costs for Hospital Returns After Total Joint Arthroplasties.

PubMed

Sibia, Udai S; Mandelblatt, Abigail E; Callanan, Maura A; MacDonald, James H; King, Paul J

2017-02-01

Unplanned hospital returns after total joint arthroplasty (TJA) reduce any cost savings in a bundled reimbursement model. We examine the incidence, risk factors, and costs for unplanned emergency department (ED) visits and readmissions within 30 days of index TJA. We retrospectively reviewed a consecutive series of 655 TJAs (382 total knee arthroplasty and 273 total hip arthroplasty) performed between April 2014 and March 2015. Preoperative diagnosis was osteoarthritis of the hip or knee (97%) or avascular necrosis of the hip (3%). Hospital costs were recorded for each ED visit and readmission episode. Of the 655 TJAs reviewed, 55 (8.4%) returned to the hospital. Of these hospital returns, 35 patients (5.3%) returned for a total of 36 unplanned ED visits whereas the remaining 20 patients (3.1%) presented 22 readmissions within 30 days of index TJA. The 2 most common reasons for unplanned ED visits were postoperative pain/swelling (36%) and medication-related side effects (22%). Avascular necrosis of the hip was a significant risk factor for an unplanned ED visit (7.27 odds ratio [OR], 95% confidence interval [CI] 1.67-31.61, P = .008). Multiple logistic regression analysis revealed the following risk factors for readmission: body mass index (1.10 OR, 95% CI 1.02-1.78, P = .013), comorbidity >2 (2.07 OR, 95% CI 1.06-6.95, P = .037), and prior total knee arthroplasty (2.61 OR, 95% CI 1.01-6.72, P = .047). Ambulating on the day of surgery trended toward a lower risk for readmission (0.13 OR, 95% CI 0.02-1.10, P = .061). The 2 most common reasons for readmission were ileus (23%) and cellulitis (18%). The total cost associated with unplanned ED visits were $15,427 whereas costs of readmissions totaled $142,654. Unplanned ED visits and readmissions in the forthcoming bundled payments reimbursement model will reduce cost savings from rapid recovery protocols for TJA. Identifying and mitigating preventable causes of unplanned visits and readmissions will be critical to improving care and controlling costs. Copyright © 2016 Elsevier Inc. All rights reserved.

Chronic complications and quality of life of patients living with sickle cell disease and receiving care in three hospitals in Cameroon: a cross-sectional study.

PubMed

Andong, Anne M; Ngouadjeu, Eveline D T; Bekolo, Cavin E; Verla, Vincent S; Nebongo, Daniel; Mboue-Djieka, Yannick; Choukem, Simeon-Pierre

2017-01-01

Sickle Cell Disease (SCD) is associated with chronic multisystem complications that significantly influence the quality of life (QOL) of patients early in their life. Although sub-Saharan Africa bears 75% of the global burden of SCD, there is a paucity of data on these complications and their effects on the QOL. We aimed to record these chronic complications, to estimate the QOL, and to identify the corresponding risk factors in patients with SCD receiving care in three hospitals in Cameroon. In this cross-sectional study, a questionnaire was used to collect data from consecutive consenting patients. Information recorded included data on the yearly frequency of painful crisis, the types of SCD, and the occurrence of chronic complications. A 36-Item Short Form (SF-36) standard questionnaire that examines the level of physical and mental well-being, was administered to all eligible participants. Data were analyzed with STATA® software. Of 175 participants included, 93 (53.1%) were female and 111 (aged ≥14 years) were eligible for QOL assessment. The median (interquartile range, IQR) age at diagnosis was 4.0 (2.0-8.0) years and the median (IQR) number of yearly painful crisis was 3.0 (1.0-7.0). The most frequent chronic complications reported were: nocturnal enuresis, chronic leg ulcers, osteomyelitis and priapism (30.9%, 24.6%, 19.4%, and 18.3% respectively). The prevalence of stroke and avascular necrosis of the hip were 8.0% and 13.1% respectively. The median (IQR) physical and mental scores were 47.3 (43.9-58.5) and 41.0 (38.8-44.6) respectively. Age and chronic complications such as stroke and avascular necrosis were independently associated with poor QOL. In this population of patients living with SCD, chronic complications are frequent and their QOL is consequently poor. Our results highlight the need for national guidelines for SCD control, which should include new-born screening programs and strategies to prevent chronic complications.

[Radiographic appraisal between metal and bone interosculate backfill after total hip arthroplasty with trabecular metal cup].

PubMed

Li, Wei; Zhou, Yi-Xin; Wu, Jian; Xu, Hui; Ji, Song-Jie

2009-02-15

To evaluate the bone refilling in the interface between the trabecular metal (TM) acetabular shell and the bone surface according to consecutive X film measuring after surgery. From July 2006 to July 2007, 35 patients (40 hips) accepted total hip replacement using trabecular metal monoblock acetabular cup system (TM). The cup was made of a ellipse shaped press fit Tantalum shell and high cross-linked PE liner (Longevity) with 28 mm inner diameter. The patients demography was: 16 male (20 hips), 19 female (20 hips), 5 bilateral hip replacements, age from 41 - 71 (mean 53), including 18 avascular necrosis hips, 16 osteoarthritis hips (including those secondary to a dysplasia hip), 4 avascular necrosis hips after femoral neck fracture, 2 Ankylosis Spondylitis. All the 40 total hip replacements used posterior approach, using hemispherical acetabular reamer and 2 mm press fit of final metal shell without screw fixation. The consecutive X film was taken at the end time of surgery and 2, 6, 12, 24 weeks, and 12 months. The clinical results was evaluate according to Harris scoring system, and the standard pelvis AP X film was measured at the interface between metal shell and the acetabular bone surface, witch was divided into five regions (A, B, C, D, E). Totally 32 patients (37 hips) were followed with average 8.7 months (7 - 12 months). The Harris before surgery was 50.5 (32 - 85), promoted to 91.0 (72 - 100), including 29 excellent, 6 good, 2 fair, and the total excellent and good rate was 94.6%. Complications include 4 patients leg length discrepancy from 1 - 2 cm, 3 patients moderate thigh pain and released after conservative therapy. No infection and dislocation was found. Twenty-one patients (23 hips) were found lucent line at the bone-metal interface from 1 - 5 mm, most common in B region and BC boundary than C, D, and CD boundary. All the patients followed was found the lucent line disappeared and refilled with bone at X film 24 weeks after surgery, however, no patients was found osteolysis and cup migration. The trabecular metal has strong capacity of bone conductive and bone inducement.

Repair of Avascular Meniscus Tears with Electrospun Collagen Scaffolds Seeded with Human Cells

PubMed Central

Baek, Jihye; Sovani, Sujata; Glembotski, Nicholas E.; Du, Jiang; Jin, Sungho; Grogan, Shawn P.

2016-01-01

The self-healing capacity of an injured meniscus is limited to the vascularized regions and is especially challenging in the inner avascular regions. As such, we investigated the use of human meniscus cell-seeded electrospun (ES) collagen type I scaffolds to produce meniscal tissue and explored whether these cell-seeded scaffolds can be implanted to repair defects created in meniscal avascular tissue explants. Human meniscal cells (derived from vascular and avascular meniscal tissue) were seeded on ES scaffolds and cultured. Constructs were evaluated for cell viability, gene expression, and mechanical properties. To determine potential for repair of meniscal defects, human meniscus avascular cells were seeded and cultured on aligned ES collagen scaffolds for 4 weeks before implantation. Surgical defects resembling “longitudinal tears” were created in the avascular zone of bovine meniscus and implanted with cell-seeded collagen scaffolds and cultured for 3 weeks. Tissue regeneration and integration were evaluated by histology, immunohistochemistry, mechanical testing, and magentic resonance imaging. Ex vivo implantation with cell-seeded collagen scaffolds resulted in neotissue that was significantly better integrated with the native tissue than acellular collagen scaffolds or untreated defects. Human meniscal cell-seeded ES collagen scaffolds may therefore be useful in facilitating meniscal repair of avascular meniscus tears. PMID:26842062

Resolution, Scales and Predictability: Is High Resolution Detrimental To Predictability At Extended Forecast Times?

NASA Astrophysics Data System (ADS)

Mesinger, F.

The traditional views hold that high-resolution limited area models (LAMs) down- scale large-scale lateral boundary information, and that predictability of small scales is short. Inspection of various rms fits/errors has contributed to these views. It would follow that the skill of LAMs should visibly deteriorate compared to that of their driver models at more extended forecast times. The limited area Eta Model at NCEP has an additional handicap of being driven by LBCs of the previous Avn global model run, at 0000 and 1200 UTC estimated to amount to about an 8 h loss in accuracy. This should make its relative skill compared to that of the Avn deteriorate even faster. These views are challenged by various Eta results including rms fits to raobs out to 84 h. It is argued that it is the largest scales that contribute the most to the skill of the Eta relative to that of the Avn.

Sudden death due to the atrioventricular node contusion

PubMed Central

Li, Wenhe; Zhang, Lin; Liang, Yue; Tong, Fang; Zhou, Yiwu

2017-01-01

Abstract Introduction: Atrioventricular node (AVN) contusion usually results in cardiogenic shock and arrhythmia and is a rare but fatal condition. The condition is difficult to diagnose and easily overlooked because it develops rapidly and is asymptomatic. We here report 3 cases that demonstrate blunt chest impact and hemorrhages of the posterior atrioventricular junction, eventually result in death. Clinical Findings: Autopsy and histological examination were performed on all cases. External inspection revealed bruises in the hearts and fractures in the sternum and ribs. However, histological examinations were conclusive and showed cardiac contusion on the surface of the posterior atrioventricular junction of the individuals, and the death was due to the AVN contusion. The position of the AVN on the heart surface is determined by detailed examinations via an autopsy and microscopic, both of which are critical in the certification of cause of death. Conclusion: The report is intended to raise our understanding and make forensic pathologists aware of the surface of the posterior atrioventricular junction. PMID:28072704

Interstitial hydraulic conductivity and interstitial fluid pressure for avascular or poorly vascularized tumors.

PubMed

Liu, L J; Schlesinger, M

2015-09-07

A correct description of the hydraulic conductivity is essential for determining the actual tumor interstitial fluid pressure (TIFP) distribution. Traditionally, it has been assumed that the hydraulic conductivities both in a tumor and normal tissue are constant, and that a tumor has a much larger interstitial hydraulic conductivity than normal tissue. The abrupt transition of the hydraulic conductivity at the tumor surface leads to non-physical results (the hydraulic conductivity and the slope of the TIFP are not continuous at tumor surface). For the sake of simplicity and the need to represent reality, we focus our analysis on avascular or poorly vascularized tumors, which have a necrosis that is mostly in the center and vascularization that is mostly on the periphery. We suggest that there is an intermediary region between the tumor surface and normal tissue. Through this region, the interstitium (including the structure and composition of solid components and interstitial fluid) transitions from tumor to normal tissue. This process also causes the hydraulic conductivity to do the same. We introduce a continuous variation of the hydraulic conductivity, and show that the interstitial hydraulic conductivity in the intermediary region should be monotonically increasing up to the value of hydraulic conductivity in the normal tissue in order for the model to correspond to the actual TIFP distribution. The value of the hydraulic conductivity at the tumor surface should be the lowest in value. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dressing up Nanoparticles: A Membrane Wrap to Induce Formation of the Virological Synapse

PubMed Central

Yu, Xinwei; Xu, Fangda; Ramirez, Nora-Guadalupe P.; Kijewski, Suzanne D. G.; Akiyama, Hisashi; Gummuluru, Suryaram; Reinhard, Björn M.

2015-01-01

Next generation nanoparticle-based drug delivery systems require the ability to target specific organelles or subcellular regions in selected target cells. Human immunodeficiency virus type I (HIV-1) particles are evolutionarily optimized nanocarriers that have evolved to avoid intracellular degradation and achieve enrichment at the synapse between mature dendritic cells (mDCs) and T cells by subverting cellular trafficking mechanisms. This study demonstrates that integration of the glycosphingolipid, GM3, in a membrane around a solid nanoparticle (NP) core is sufficient to recapitulate key aspects of the virus particle trafficking in mDCs. GM3 presenting artificial virus NPs (GM3-AVNs) accumulate in CD169+, CD81+, non-lysosomal compartments in an actin-dependent process that mimics the sequestration of HIV-1. Live-cell optical tracking studies reveal a preferential recruitment and arrest of surface scanning CD4+ T cells in direct vicinity to the AVN-enriched compartments. The formed mDC-T cell conjugates exhibit strong morphological similarities between the GM3-AVN-containing mDC-T cell synapse and the HIV-1 virological synapse, indicating that GM3-CD169 interactions alone are sufficient for establishing the mDC-T cell virological synapse. These results emphasize the potential of the GM3-AVN approach for providing therapeutic access to a key step of the host immune response – formation of the synaptic junction between an antigen-presenting cell (mDC) and T cells – for modulating and controlling immune responses. PMID:25853367

Using GPS radio occultation data in the study of tropical cyclogenesis

NASA Astrophysics Data System (ADS)

Didlake, A. C., Jr.; Kuo, Y. B.; Metcalfe, T.

2005-12-01

Numerous studies have examined atmospheric conditions and patterns in tropical cyclogenesis. Although much has been accomplished, a complete understanding of tropical cyclogenesis is hindered by the lack of data in the regions where formation occurs. The GPS (Global Positioning System) radio occultation technique can provide valuable data in key areas. In GPS radio occultation, GPS satellites emit radio signals through the atmosphere that are received by another satellite in a low Earth orbit. Various atmospheric properties are calculated based on the alteration of the signal. This study assessed the value of GPS radio occultation data in the study of tropical cyclogenesis by examining storms of the 2002 Western North Pacific typhoon season. The signature of precursor disturbances to tropical cyclogenesis was determined by analyzing composites of data from the NCEP Aviation (AVN) analysis over four days. Similar composites of GPS radio occultation data were produced. The AVN analysis showed strong signals of precursor disturbances in the low-level wind fields and atmospheric refractivity. The GPS radio occultation data detected similarly increased refractivity values in corresponding regions, but had sizeable measurement differences with the AVN analysis. These differences were attributed to AVN analysis error due to the lack of input observational data and the high accuracy of GPS radio occultation measurements. Further comparisons showed that with the limited quantity of data currently available, GPS radio occultation by itself was not sufficient to detect precursor disturbances. It can best be used in data assimilation to improve the analysis and forecasts of tropical storms.

Inhibition of spontaneous activity of rabbit atrioventricular node cells by KB-R7943 and inhibitors of sarcoplasmic reticulum Ca2+ ATPase

PubMed Central

Cheng, Hongwei; Smith, Godfrey L.; Hancox, Jules C.; Orchard, Clive H.

2011-01-01

The atrioventricular node (AVN) can act as a subsidiary cardiac pacemaker if the sinoatrial node fails. In this study, we investigated the effects of the Na–Ca exchange (NCX) inhibitor KB-R7943, and inhibition of the sarcoplasmic reticulum calcium ATPase (SERCA), using thapsigargin or cyclopiazonic acid (CPA), on spontaneous action potentials (APs) and [Ca2+]i transients from cells isolated from the rabbit AVN. Spontaneous [Ca2+]i transients were monitored from undialysed AVN cells at 37 °C using Fluo-4. In separate experiments, spontaneous APs and ionic currents were recorded using the whole-cell patch clamp technique. Rapid application of 5 μM KB-R7943 slowed or stopped spontaneous APs and [Ca2+]i transients. However, in voltage clamp experiments in addition to blocking NCX current (INCX) KB-R7943 partially inhibited L-type calcium current (ICa,L). Rapid reduction of external [Na+] also abolished spontaneous activity. Inhibition of SERCA (using 2.5 μM thapsigargin or 30 μM CPA) also slowed or stopped spontaneous APs and [Ca2+]i transients. Our findings are consistent with the hypothesis that sarcoplasmic reticulum (SR) Ca2+ release influences spontaneous activity in AVN cells, and that this occurs via [Ca2+]i-activated INCX; however, the inhibitory action of KB-R7943 on ICa,L means that care is required in the interpretation of data obtained using this compound. PMID:21163524

WE-EF-BRA-03: Catheter- Free Ablation with External Photon Radiation: Treatment Planning, Delivery Considerations, and Correlation of Effects with Delivered Dose

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deisher, A; Anderson, S; Cusma, J

Purpose: To plan, target, and calculate delivered dose in atrioventricular node (AVN) ablation with volume-modulated arc therapy (VMAT) in an intact porcine model. Methods: Seven pigs underwent AVN irradiation, with prescription doses ranging between 25 and 55Gy in a single fraction. Cardiac CT scans were acquired at expiration. Two physicians contoured AVN targets on 10 phases, providing estimates of target motion and inter-physician variability. Treatment planning was conducted on a static phase-averaged CT. The volume designated to receive prescription dose covered the full extent of AVN cardiac motion, expanded by 4mm for setup uncertainty. Optimization limited doses to risk structuresmore » according to single-fraction tumor treatment protocols. Orthogonal kV images were used to align bony anatomy at time of treatment. Localization was further refined with respiratory-gated cone-beam CT, and range of cardiac motion was verified under fluoroscopy. Beam delivery was respiratory-gated for expiration with a mean efficiency of 60%. Deformable registration of the 10 cardiac CT phases was used to calculate actual delivered dose for comparison to electro-anatomical and visually evident lesions. Results: The mean [minimum,maximum] amplitude of AVN cardiac motion was LR 2.9 [1.7,3.9]mm, AP 6.6 [4.4,10.4]mm, and SI 5.6 [2.0,9.9]mm. Incorporating cardiac motion into the dose calculation showed the volume receiving full dose was 40–80% of the volume indicated on the static planning image, although the contoured AVN target received full dose in all animals. Initial results suggest the dimensions of the electro-anatomical lesion are correlated with the 40Gy isodose volume. Conclusion: Image-guidance techniques allow for accurate and precise delivery of VMAT for catheter-free arrhythmia ablation. An arsenal of advanced radiation planning, dose optimization, and image-guided delivery techniques was employed to assess and mitigate effects of cardiac and respiratory motion. Feasibility of delivery to the pulmonary veins and left ventricular myocardium will be investigated in future studies. D. Packer Disclosures: Abiomed, Biosense Webster, Inc., Boston Scientific Corp., CardioFocus, Inc., Johnson and Johnson, Excerpta Medica, Ortho-McNeil-Jannsen, Sanofi Aventis, CardioInsight Technologies, InfoBionic, SIEMENS, Medtronic, Inc., CardioDx, Inc., CardioInsight Technologies, FoxP2 Medica, Mediasphere Medical, Wiley-Blackwell, St. Jude Medical, Endosense, Thermedical, EP Advocate LLC, Hansen Medical, American Heart Association, EpiEP, NIH.« less

Tibiotalocalcaneal Arthrodesis Using a Nitinol Intramedullary Hindfoot Nail.

PubMed

Hsu, Andrew R; Ellington, J Kent; Adams, Samuel B

2015-10-01

Tibiotalocalcaneal (TTC) arthrodesis using an intramedullary hindfoot nail is a common procedure for deformity correction and the treatment of combined tibiotalar and subtalar end-stage arthritis. Nonunion at one or both fusion sites is a difficult complication that can result in reoperation, significant morbidity, and below-knee amputation. There is currently a need for sustained compression across fusion sites using a TTC hindfoot nail with good mechanical stability. The DynaNail TTC Fusion System (MedShape, Inc, Atlanta, GA) uses an internal nitinol compression element to apply sustained compression across the tibiotalar and subtalar joints after surgery. In preliminary clinical cases, we have found that the nail is safe, reliable, and has promising clinical and radiographic results in settings of hindfoot arthritis, complex deformity, Charcot arthropathy, and talar avascular necrosis. Expert opinion, Level V. © 2015 The Author(s).

Congenital insensitivity to pain. Orthopaedic manifestations.

PubMed

Bar-On, E; Weigl, D; Parvari, R; Katz, K; Weitz, R; Steinberg, T

2002-03-01

We reviewed 13 patients with congenital insensitivity to pain. A quantitative sweat test was carried out in five and an intradermal histamine test in ten. DNA examination showed specific mutations in four patients. There were three clinical presentations: type A, in which multiple infections occurred (five patients); type B, with fractures, growth disturbances and avascular necrosis (three patients); and type C, with Charcot arthropathies and joint dislocations, as well as fractures and infections (five patients, four with mental retardation). Patient education, shoeware and periods of non-weight-bearing are important in the prevention and early treatment of decubitus ulcers. The differentiation between fractures and infections should be based on aspiration and cultures to prevent unnecessary surgery. Established infections should be treated by wide surgical debridement. Deformities can be managed by corrective osteotomies, and shortening by shoe raises or epiphysiodesis. Joint dislocations are best treated conservatively.

Assessment and Management of Musculoskeletal Disorders Among Patients Living with HIV

PubMed Central

Walker-Bone, Karen; Doherty, Erin; Sanyal, Kaushik; Churchill, Duncan

2017-01-01

HIV is a global pandemic. However, anti-retroviral therapy (ART) has transformed the prognosis and providing compliance is good, a normal life expectancy can be anticipated. This has led to a growing population of people with chronic prevalent, treated infection living to older ages. Musculoskeletal symptoms, particularly musculoskeletal pain, is common in HIV patients and, with resumption of near-normal immune function, HIV-infected patients develop inflammatory rheumatic diseases which require assessment and management in rheumatology clinics. Moreover, it is becoming apparent that avascular necrosis and osteoporosis are common comorbidities of HIV. This review will contextualise the prevalence of musculoskeletal symptoms in HIV, informed by data from a UK-based clinic and will discuss the management of active inflammatory rheumatic diseases amongst HIV-infected patients taking ART, highlighting known drug interactions. PMID:28013196

Bilateral Femoral Neck Fatigue Fracture due to Osteomalacia Secondary to Celiac Disease: Report of Three Cases.

PubMed

Selek, Ozgur; Memisoglu, Kaya; Selek, Alev

2015-08-01

Bilateral non traumatic femoral neck fatigue fracture is a rare condition usually occurring secondary to medical conditions such as pregnancy, pelvic irradiation, corticosteroid exposure, chronic renal failure and osteomalacia. In this report, we present three young female patients with bilateral femoral neck fracture secondary to osteomalacia. The underlying cause of osteomalacia was Celiac disease in all patients. The patients were treated with closed reduction and internal fixation with cannulated lag screws. They were free of pain and full weight bearing was achieved at three months. There were no complications, avascular necrosis and nonunion during the follow up period. In patients with bone pain, non traumatic fractures and muscle weakness, osteomalacia should be kept in mind and proper diagnostic work-up should be performed to identify the underlying cause of osteomalacia such as celiac disease.

Flexor Tendon Rupture Due to Previously Undiagnosed Kienböck Disease: A Case Report.

PubMed

Turner, Kenrick; Sheppard, Nicholas N; Norton, Samuel E

2017-05-01

Spontaneous flexor tendon rupture is rare and most common in the little finger. The pathogenesis of spontaneous tendon ruptures is unclear but may occur through attrition or mechanical abrasion over a bony prominence. Kienböck disease is avascular necrosis of the lunate, with an unknown etiology. We present a case of spontaneous rupture of flexor digitorum profundus due to Kienböck disease, which we believe is the first recorded case of flexor tendon rupture attributable to osteonecrosis of the lunate. The patient underwent single-stage reconstruction of FDP and regained a good range of motion at the affected DIPJ. This case illustrates the the importance of plain radiographs in the assessment of a patient presenting with spontaneous flexor tendon rupture in the hand to exclude bony pathology as a cause.

Minimally invasive unicompartmental knee replacement: retrospective clinical and radiographic evaluation of 83 patients.

PubMed

Bruni, Danilo; Iacono, Francesco; Russo, Alessandro; Zaffagnini, Stefano; Marcheggiani Muccioli, Giulio Maria; Bignozzi, Simone; Bragonzoni, Laura; Marcacci, Maurilio

2010-06-01

We performed a retrospective clinical and radiographic evaluation of 83 nonconsecutive patients operated in our institute between February 1996 and March 2003 with a mean follow-up of 60 months to assess the efficiency of unicompartmental knee replacement (UKR) performed with a minimally invasive technique. The aim of this study was to correlate the clinical outcome with the pre- and post-operative alignment and with implant positioning on coronal and sagittal plane. Eighty-three nonconsecutive patients (60 males, 23 females) underwent cemented UKR (De Puy Preservation Uni with all-poly tibial component), for both medial OA (80 patients) and AVN of the medial femoral condyle (3 patients). All patients were available at final follow-up evaluation, and they all presented an evident varus alignment at pre-operative clinical and radiographic evaluation. At radiographic measurement, we considered a knee with femoro-tibial angle (FTA) > 175 degrees as varus knee, 170 degrees < FTA < 175 degrees as normal knee and a knee with a FTA < 170 degrees as a valgus knee. Moreover, we considered a tibial plateau angle (TPA) > 90 degrees for valgus knee and a TPA < 90 degrees for varus knee. According to Hospital for Special Surgery (HSS) scoring system, at a mean follow-up of 60 months, 61 (74%) cases were excellent (100-85 points), 15 (18%) cases were good (84-70 points) and 7 cases (8%) had fair results (<70 points). In our series, patients with an excellent clinical result presented a mean varus deformity of 7.2 degrees (3.6 degrees-10.8 degrees) pre-operatively. According to literature, we demonstrated that a small amount of undercorrection with a small amount of residual varus deformity of 3 degrees-5 degrees is the goal to be reached in order to avoid both rapid degeneration of the nonreplaced compartment and the premature loosening of the replaced compartment. We performed a mean axial correction of 5 degrees (SD 3.9 degrees), leaving a mean axial varus deformity of 2.2 degrees in the excellent group. In our series, the group with excellent results also showed a post-operative PTS of 7 degrees (2.4 degrees-11.6 degrees), while mean pre-operative PTS was 6.5 degrees (2.7 degrees-10.3 degrees). In this study, results have shown that minimally invasive UKR producing a small amount of varus undercorrection in selected patients with medial tibio-femoral osteoarthritis or moderate avascular necrosis of the medial femoral condyle provides excellent clinical and functional results. Overcorrection of varus malalignment with a UKR may produce both rapid degeneration of the lateral tibio-femoral compartment and the early failure of the replaced compartment.

Therapeutic effect of Aloe vera and silver nanoparticles on acid-induced oral ulcer in gamma-irradiated mice.

PubMed

El-Batal, Ahmed Ibrahim; Ahmed, Salwa Farid

2018-02-05

Radiation combined injury, a life-threatening condition, has higher mortality than simple radiation injury. The aim of the present study was to analyze the efficiency of Aloe vera and silver nanoparticles in improving the healing of ulcerated oral mucosa after irradiation. Thirty male Albino mice were divided into five groups: control, radiation, Aloe vera (AV), silver nanoparticles (NS), and AV+NS. The mice were exposed to whole body 6Gy gamma-radiation. After one hour, 20% acetic acid was injected into the submucosal layer of the lower lip for ulcer induction. The animals received topical treatment with the assigned substances for 5 days. Lip specimens were subjected to hematoxylin and eosin and anti alpha-smooth muscle actin immunohistochemical staining. Results demonstrated occurance of ulcer three days post irradiation in all groups except in the AV+NS group where only epithelial detachment was developed. After seven days, data revealed persistent ulcer in radiation group, and almost normal epithelium in the AV+NS group. A significant reduction of epithelial thickness was detected in all groups at the third day as compared to control. At the seventh day, only the AV+NS group restored the epithelial thickness. Area percent of alpha-smooth muscle actin expression was significantly decreased in radiation group at the third day followed by significant increase at the seventh day. However, all treatment groups showed significant increase in alpha-smooth muscle actin at the third day, which decreased to normal level at the seventh day. Our study demonstrated the efficiency of Aloe vera and silver nanoparticles in enhancing ulcer healing after irradiation.

Web-based Teaching Radio Interferometer for Africa

NASA Astrophysics Data System (ADS)

Carignan, Claude

2015-08-01

Practical training for the future use of the African VLBI Network (AVN) or any VLBI experiment starts by understanding the basic principles of radio observations and radio interferometry. The aim of this project is to build a basic interferometer that could be used remotely via a web interface from any country on the African continent. This should turn out as a much less expensive and much more efficient way to train AVN researchers from SKA partner countries to the principles of radio astronomy and to interferometric data analysis. The idea is based on the very successful EUHOU (European Hands-On Universe) already very successful in Europe. The former EUHOU manager, Dr Yannick Liebert, arrived for a 3 years postdoc with Prof Claude Carignan at the University of Cape Town to implement the same project on the African continent (AHI: African Hands-on Interferometry). Besides the use of AHI for the AVN researchers, this web-based system could be used be any undergraduate program on radio astronomical techniques across the African continent as the EUHOU is used all across Europe.

Center for Integration of Medicine and Innovative Technology

DTIC Science & Technology

2006-11-01

therapy could be one therapeutic approach for repairing tears in the avascular zone of the knee meniscus cartilage. In previous studies in the...studies were performed in a vascular subcutaneous environment, which is different from the avascular articular environment of the knee joint. The... avascular inner third. Although further investigation is still needed to define the best delivery material and the best pre-seeding conditions of the

Center for Integration of Medicine and Innovative Technology

DTIC Science & Technology

2007-11-01

therapy could be one therapeutic approach for repairing tears in the avascular zone of the knee meniscus cartilage. In previous studies in the...studies were performed in a vascular subcutaneous environment, which is different from the avascular articular environment of the knee joint. The... avascular inner third. Although further investigation is still needed to define the best delivery material and the best pre-seeding conditions of the

Phase transition in tumor growth: I avascular development

NASA Astrophysics Data System (ADS)

Izquierdo-Kulich, E.; Rebelo, I.; Tejera, E.; Nieto-Villar, J. M.

2013-12-01

We propose a mechanism for avascular tumor growth based on a simple chemical network. This model presents a logistic behavior and shows a “second order” phase transition. We prove the fractal origin of the empirical logistics and Gompertz constant and its relation to mitosis and apoptosis rate. Finally, the thermodynamics framework developed demonstrates the entropy production rate as a Lyapunov function during avascular tumor growth.

Modification of atrioventricular nodal electrophysiology by selective radiofrequency delivery on the anterior or posterior approaches.

PubMed

Chorro, F J; Sanchis, J; Such, L; Artal, L; Llavador, J J; Llavador, E; Monmeneu, J V; López-Merino, V

1997-05-01

An analysis was made in 14 isolated and perfused rabbit hearts of the electrophysiological effects of selective radiofrequency (RF) delivery in the anterior (group I, n = 7) or posterior zone (group II, n = 7) of the Koch triangle, with the aim of modifying atrioventricular nodal (AVN) conduction without suppressing 1:1 transmission. After opening the right atrium, RF was delivered (0.5 W) with a 1-mm diameter unipolar electrode positioned in the selected zone until a prolongation of no less than 15% was obtained in the Wenckebach cycle length (WCL). Before and after (30 min) RF, anterograde and retrograde AVN refractoriness and conduction were evaluated, stimulating from the crista terminalis (CT), the interatrial septum (IAS), and from the RV epicardium. After RF, the following percentage increments were observed in group I: AH(CT) = 36% +/- 9%, AH(IAS) = 38% +/- 11%, WCL(CT) = 28% +/- 8%, WCL(IAS) = 22% +/- 6%, functional refractory period (FRP) of the AVN(CT) = 13% +/- 11%, FRP-AVN(IAS) = 13% +/- 8%, retrograde WCL = 20% +/- 19%, and retrograde FRPVA = 13% +/- 16%. The increments observed in group II and the significances of the differences with respect to group I were: AH(CT) = 11% +/- 14% (P < 0.01), AH(IAS) = 19% +/- 32% (NS), WCL(CT) = 42% +/- 14% (P < 0.05), WCL(IAS) = 42% +/- 16% (P < 0.01), FRP-AVN(CT) = 28% +/- 28% (NS), FRP-AVN(LAS) = 21% +/- 19% (NS), retrograde WCL = 35% +/- 24% (NS), and retrograde FRP = 16% +/- 13% (NS). In both groups, the AH interval variations were not correlated with those of the rest of the parameters analyzed. Truncated nodal function curves suggestive of a dual AV nodal pathway were obtained in three experiments, though in only one of them was this observed under basal conditions. In the other two experiments, with dual AV nodal physiology only after RF (one from each group), AV nodal reentrant tachycardias were triggered with atrial extrastimulus at coupling intervals equal to or shorter than at those that cause a sudden lengthening of the AH interval, RF delivered in the anterior and posterior zones of the Koch triangle produced effects of different magnitude on the AH interval and Wenckebach cycle length. In the anterior zone the AH interval was prolonged to a greater extent, while in the posterior zone the effects were greater on the Wenckebach cycle length. No correlation existed between the variations in AH interval and Wenckebach cycle length, regardless of where RF was delivered. The evaluation of anterograde AV nodal refractoriness was similar when stimulating from the crista terminalis or from the interatrial septum. By delivering RF, it was possible to induce dual AV nodal physiology and reentrant tachycardias.

Hybrid laparoscopic and robotic ultrasound-guided radiofrequency ablation-assisted clampless partial nephrectomy.

PubMed

Nadler, Robert B; Perry, Kent T; Smith, Norm D

2009-07-01

To describe a clampless approach made possible by creating an avascular plane of tissue with radiofrequency ablation. Laparoscopic partial nephrectomy is slowly gaining acceptance as a method to treat small (<4 cm) and select moderate (<7 cm) renal masses. The intricacies of laparoscopic suturing, which result in prolonged warm ischemia times, have delayed the widespread acceptance of this technique among urologists. Laparoscopic suturing to close the collecting system was done using the da Vinci robot. An avascular plane of tissue from coagulation necrosis was achieved with the Habib 4X radiofrequency ablation device and the Rita 1500X generator. Typically, we used a power setting of 50 W but have found settings as low as 25 W necessary to provide hemostasis for larger vessels. The tumor was then sharply excised with a negative margin using robotic scissors and electrocautery to facilitate tissue cutting. Retrograde injection of methylthioninium chloride and saline through an externalized ureteral catheter allowed for precise sutured closure of the collecting system. FloSeal and BioGlue were then applied, making surgical bolsters or parenchymal sutures unnecessary. Intraoperative histologic evaluation of the surgical margin and repeat resection of the tumor bed was possible because the renal hilum was not clamped, and no warm ischemia was used. This technique, which combines the improving technologies of robotic surgery, intraoperative laparoscopic ultrasonography, and radiofrequency ablation, might make more surgeons comfortable with the intricacies of laparoscopic suturing and eliminate prolonged warm ischemia times. Overall, this method should result in more patients being able to undergo minimally invasive laparoscopic partial nephrectomy.

Shock wave treatment in medicine.

PubMed

Shrivastava, S K; Kailash

2005-03-01

Extracorporeal shock wave therapy in orthopedics and traumatology is still a young therapy method. Since the last few years the development of shock wave therapy has progressed rapidly. Shock waves have changed the treatment of urolithiasis substantially. Today shock waves are the first choice to treat kidney and urethral stones. Urology has long been the only medical field for shock waves in medicine. Meanwhile shock waves have been used in orthopedics and traumatology to treat insertion tendinitis, avascular necrosis of the head of femur and other necrotic bone alterations. Another field of shock wave application is the treatment of tendons, ligaments and bones on horses in veterinary medicine. In the present paper we discuss the basic theory and application of shock waves and its history in medicine. The idea behind using shock wave therapy for orthopedic diseases is the stimulation of healing in tendons, surrounding tissue and bones.

MR imaging of the pelvis: a guide to incidental musculoskeletal findings for abdominal radiologists.

PubMed

Gaetke-Udager, Kara; Girish, Gandikota; Kaza, Ravi K; Jacobson, Jon; Fessell, David; Morag, Yoav; Jamadar, David

2014-08-01

Occasionally patients who undergo magnetic resonance imaging for presumed pelvic disease demonstrate unexpected musculoskeletal imaging findings in the imaged field. Such incidental findings can be challenging to the abdominal radiologist, who may not be familiar with their appearance or know the appropriate diagnostic considerations. Findings can include both normal and abnormal bone marrow, osseous abnormalities such as Paget's disease, avascular necrosis, osteomyelitis, stress and insufficiency fractures, and athletic pubalgia, benign neoplasms such as enchondroma and bone island, malignant processes such as metastasis and chondrosarcoma, soft tissue processes such as abscess, nerve-related tumors, and chordoma, joint- and bursal-related processes such as sacroiliitis, iliopsoas bursitis, greater trochanteric pain syndrome, and labral tears, and iatrogenic processes such as bone graft or bone biopsy. Though not all-encompassing, this essay will help abdominal radiologists to identify and describe this variety of pelvic musculoskeletal conditions, understand key radiologic findings, and synthesize a differential diagnosis when appropriate.

Cyclosporine and Vancomycin + Amikacin Induced Hot Kidney Appearance in a Young Adult and a Pediatric Patient.

PubMed

Çayır, Derya; Araz, Mine; Filik, Mustafa; Erdoğan, Mehmet

2017-10-03

The appearance of a hot kidney on bone scintigraphy is rare and can be seen due to various factors. In our clinic, we observed hot kidney appearance in two patients to whom technetium-99m methylene diphosphonate (Tc-99m MDP) whole body scan has been performed: a young male adult at the age of 18 who was diagnosed with acute lymphocytic leukemia with a presumptive diagnosis of avascular necrosis, and a 9-year-old girl with cystitis for a pre-diagnosis of osteomyelitis. The first patient had a history of cyclosporine usage and the second patient was being treated with amikacin + vancomycin. To the best of our knowledge, we present the first cases where hot-kidney appearance on Tc-99m MDP whole body scan due to the use of cyclosporin and amikacin + vancomycin is demonstrated.

Neck osteotomy for malunion of neglected radial neck fractures in children: a report of 2 cases.

PubMed

Ceroni, Dimitri; Campos, José; Dahl-Farhoumand, Agnes; Holveck, Jérôme; Kaelin, André

2010-01-01

Radial neck fractures are a common injury in children as a result of a fall on an extended and supinated outstretched hand. We present 2 cases of osteotomy of the neck of the radius performed in 2 children with neglected radial neck fractures. Preoperatively, both patients complained of pain and severely reduced mobility of the elbow. Surgery was performed at 6 weeks and 3 months, respectively, after the initial injury and the 2 children were reviewed at 6 and 16 months follow-up. Osteotomies healed within the usual time and no avascular necrosis of the radial head, proximal radioulnar synostosis, or myositis ossificans were observed. The Mayo Elbow Performance Index Score improved significantly after the operation with the 2 patients rated as excellent. In this small series, we present a novel technique of proximal osteotomy of the radius to correct this deformity in children. Case series, level IV evidence.

Bronchoscopic phototherapy at comparable dose rates: Early results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pass, H.I.; Delaney, T.; Smith, P.D.

1989-05-01

Photodynamic therapy is a recently introduced treatment for surface malignancies. Since January 1987, 10 patients with endobronchial neoplasms have had bronchoscopic photodynamic therapy at similar dose rates (400 mW/cm) for total atelectasis (2), carinal narrowing with respiratory insufficiency (2), or partial obstruction without collapse (4). Two patients underwent photodynamic therapy as a preliminary to immunotherapy. Histologies included endobronchial metastases (colon, ovary, melanoma, and sarcoma, 1 each; and renal cell, 3) and primary lung cancer (3). The 2 patients with total atelectasis had complete reexpansion after photodynamic therapy, which permitted eventual sleeve lobectomy in 1. Carinal narrowing was ameliorated in themore » 2 patients seen with inspiratory stridor, thereby permitting hospital discharge. Endoscopically resected fragments after photodynamic therapy exhibited avascular necrosis. These data support further controlled studies of photodynamic therapy by thoracic surgical oncologists to define its limitations as well as to improve and expand its efficacy as a palliative or surgical adjuvant.« less

Delayed surgical treatment for neglected or mal-reduced talar fractures.

PubMed

Huang, Peng-Ju; Cheng, Yuh-Min

2005-10-01

From 1993 to 2002, we treated nine patients for neglected or mal-reduced talar fractures. Average patient age was 39 (20-64) years and average follow-up 53 months. The time interval between injury and index operation ranged from 4 weeks to 4 years. Surgical procedures included open reduction with or without bone grafting in six cases, open reduction combined with ankle fusion in one case, talar neck osteotomy in one case, and talar neck osteotomy combined with subtalar fusion in one case. All cases had solid bone union. One patient developed avascular necrosis of the talus needing subsequent ankle arthrodesis. In six patients, adjacent hindfoot arthrosis occurred. The overall AOFAS ankle-hindfoot score was in average 77.4. We conclude that in neglected and mal-reduced talar fractures, surgical treatment can lead to a favourable outcome if the hindfoot joints are not arthritic.

[Bursitis iliopectinea].

PubMed

Koudela, K; Koudelová, J; Koudela, K; Kunesová, M

2008-10-01

PURPOSE OF THE STUDY To present clinical and radiographic findings of iliopectineal bursitis and draw attention to some related etiopathogenetic factors. MATERIAL AND METHODS Six patients followed up between 2005 and 2007 were evaluated. They included four women and two men (average age, 58 years; range, 35 to 80 years) who presented with a tender mass in the hip region (four right and two left sides). Each patient underwent an examination involving a clinical check-up, imaging methods (CT, MR, angio-CT) and standard laboratory tests. RESULTS Iliopectineal bursitis clinically manifested as a tender mass in the groin and hip region in five patients; in one it was pulsating. The sixth case was asymptomatic. In three patients iliopectineal bursitis was found in association with steroid therapy and subsequent avascular necrosis of the femoral head and chronic synovitis. It followed tularemia with hip joint involvement in one patient, salmonella arthritis in one, and kidney transplant rejection in one. Also, iliopectineal bursitis was diagnosed in a patient with rheumatoid arthritis treated with steroids, but without femoral head avascular necrosis, and was incidentally found in another patient examined for digestive problems. Of the six cases of swollen bursa detected by the imaging methods used, five were found to communicate with the hip joint cavity, with four being so large that the bursa extended into the retroperitoneum. Two patients underwent excision or resection of the bursa; in addition, one of them had revitalizing graft surgery for femoral head necrosis. The patient with salmonella arthritis had to undergo a Girdlestone procedure. One patient was treated by draining of the bursa and, after inflammation resolved, total hip replacement surgery was carried out during which the iliopectineal bursa was removed. The patient with rheumatoid arthritis was treated by bursa draining and refused further surgical therapy (total hip replacement). DISCUSSION In our group of six patients, bursitis was symptomatic in five and was associated with chronic hip synovitis accompanying femoral head necrosis following steroid therapy or inflamation, either non-specific or arthitic. Bursitis was asymptomatic in one patient and was diagnosed only incidentally on CT examination done for another reason. The communication between the bursa and the hip joint cavity, found on CT scans and magnetic resonance images, was a radiographic factor important for differential diagnosis. The underlying disease of the hip joint plays a key role in the etiopathogenesis of iliopectineal bursitis. Therefore, surgical treatment should be comprehensible and, in addition to bursa resection or excision, should also include treatment of the affected joint (alloplasty, femoral head resection or revitalization). CONCLUSION Iliopectineal bursitis is associated with chronic hip synovitis present in degenerative, infectious or rheumatic joint diseases. When a lump is diagnosed in the inguinal or hip region, iliopectineal bursitis should always be considered in addition to conditions such as abscess, cyst, hernia, pseudoaneurysm, lymphocele, etc. The finding of communication beteen the bursa and hip joint cavity, made on CT scans or magnetic resonance images, is a radiographic factor important in terms of differential diagnosis. The surgical treatment of iliopectineal bursitis includes excision or resection of the bursa and therapy for the hip joint (alloplasty, femoral head resection or revitalization).

AVN-211, Novel and Highly Selective 5-HT6 Receptor Small Molecule Antagonist, for the Treatment of Alzheimer's Disease.

PubMed

Ivachtchenko, Alexandre V; Lavrovsky, Yan; Ivanenkov, Yan A

2016-03-07

Within the past decade several novel targets have been indicated as key players in Alzheimer-type dementia and associated conditions, including a "frightening" memory loss as well as severe cognitive impairments. These proteins are deeply implicated in crucial cell processes, e.g., autophagy, growth and progression, apoptosis, and metabolic equilibrium. Since recently, 5-HT6R has been considered as one of the most prominent biological targets in AD drug therapy. Therefore, we investigated the potential procognitive and neuroprotective effects of our novel selective 5-HT6R antagonist, AVN-211. During an extensive preclinical evaluation the lead compound demonstrated a relatively high therapeutic potential and improved selectivity toward 5-HT6R as compared to reference drug candidates. It was thoroughly examined in different in vivo behavioral models directly related to AD and showed evident improvements in cognition and learning. In many cases, the observed effect was considerably greater than that determined for the reported drugs and drug candidates, including memantine, SB-742457, and Lu AE58054, evaluated under the same conditions. In addition, AVN-211 showed a similar or better anxiolytic efficacy than fenobam, rufinamide, lorazepam, and buspirone in an elevated plus-maze model, elevated platform, and open field tests. The compound demonstrated low toxicity and no side effects in vivo, an appropriate pharmacokinetic profile, and stability. In conclusion, AVN-211 significantly delayed or partially halted the progressive decline in memory function associated with AD, which makes it an interesting drug candidate for the treatment of neurodegenerative and psychiatric disorders. Advanced clinical trials are currently under active discussion and in high priority.

Safety and feasibility of leadless pacemaker in patients undergoing atrioventricular node ablation for atrial fibrillation.

PubMed

Yarlagadda, Bharath; Turagam, Mohit K; Dar, Tawseef; Jangam, Pragna; Veerapaneni, Vaishnavi; Atkins, Donita; Bommana, Sudharani; Friedman, Paul; Deshmukh, Abhishek J; Doshi, Rahul; Reddy, Vivek Y; Dukkipati, Srinivas R; Natale, Andrea; Lakkireddy, Dhanunjaya

2018-03-01

Atrioventricular node (AVN) ablation and permanent pacing is an established strategy for rate control in the management of symptomatic atrial fibrillation (AF). Leadless pacemakers (LPs) can overcome some of the short-term and long-term limitations of conventional transvenous pacemakers (CTPs). The purpose of this study was to compare the feasibility and safety of LP with those of single-chamber CTP in patients with AF undergoing AVN ablation. We conducted a multicenter observational study of patients undergoing AVN ablation and pacemaker implantation (LP vs single-chamber CTP) between February 2014 and November 2016. The primary efficacy end points were acceptable sensing (R wave ≥5.0 mV) and pacing thresholds (≤2.0 V at 0.4 ms) at follow-up. Safety end points included device-related major and minor (early ≤1 month, late >1 month) adverse events. A total of 127 patients with LP (n = 60) and CTP (n = 67) were studied. The median follow-up was 12 months (interquartile range 12-18 months). Ninety-five percent of the LP group and 97% of the CTP group met the primary efficacy end point at follow-up (57 of 60 vs 65 of 67; P = .66). There was 1 major adverse event (loss of pacing and sensing) in the LP group and 2 (lead dislodgement) in the CTP group (1 of 60 vs 2 of 67; P = 1.00). There were 6 minor adverse events (5 early and 1 late) in the LP group and 3 (early) in the CTP group (6 of 60 vs 3 of 67; P = .30). Our results demonstrate the feasibility and safety of LP compared with CTP in patients undergoing AVN ablation for AF. Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Nailfold capillaroscopy abnormalities as predictors of mortality in patients with systemic sclerosis.

PubMed

Kayser, Cristiane; Sekiyama, Juliana Y; Próspero, Lucas C; Camargo, Cintia Z; Andrade, Luis E C

2013-01-01

Peripheral microangiopathy is a hallmark of systemic sclerosis (SSc) and can be early detected by nailfold capillaroscopy (NFC). This study aimed to examine whether more severe peripheral microangiopathy at NFC are predictive factor for death in SSc patients. 135 SSc patients who performed NFC between June 2001 and July 2009 were included. The following NFC parameters were evaluated: number of capillary loops/mm, avascular score (scored from 0 to 3), and number of enlarged and giant capillary loops. Univariate and multivariate regression models were used to analyse the association of mortality with NFC and clinical parameters. At the time of the analysis (August 2010), 123 patients were alive, and 12 were dead. By univariate analysis, male gender, forced vital capacity <75% predicted, higher number of giant capillary loops, and an avascular score >1.5 on NFC were associated with a significantly increase risk of death. By multivariate analysis, an avascular score >1.5 was the only independent predictor of death (hazard ratio 2.265). Survival rates from diagnosis at 1, 5 and 10 years were lower in patients with avascular score >1.5 (97%, 86%, and 59%, respectively) compared with those with avascular score ≤1.5 (97%, 97%, and 91% respectively) (p=0.009 by log rank test). Avascular scores higher than 1.5 at NFC was an independent predictor of death in SSc, suggesting that NFC can be useful for predicting SSc outcome.

The impact of high total cholesterol and high low-density lipoprotein on avascular necrosis of the femoral head in low-energy femoral neck fractures.

PubMed

Zeng, Xianshang; Zhan, Ke; Zhang, Lili; Zeng, Dan; Yu, Weiguang; Zhang, Xinchao; Zhao, Mingdong; Lai, Zhicheng; Chen, Runzhen

2017-02-17

Avascular necrosis of the femoral head (AVNFH) typically constitutes 5 to 15% of all complications of low-energy femoral neck fractures, and due to an increasingly ageing population and a rising prevalence of femoral neck fractures, the number of patients who develop AVNFH is increasing. However, there is no consensus regarding the relationship between blood lipid abnormalities and postoperative AVNFH. The purpose of this retrospective study was to investigate the relationship between blood lipid abnormalities and AVNFH following the femoral neck fracture operation among an elderly population. A retrospective, comparative study was performed at our institution. Between June 2005 and November 2009, 653 elderly patients (653 hips) with low-energy femoral neck fractures underwent closed reduction and internal fixation with cancellous screws (Smith and Nephew, Memphis, Tennessee). Follow-up occurred at 1, 6, 12, 18, 24, 30, and 36 months after surgery. Logistic multi-factor regression analysis was used to assess the risk factors of AVNFH and to determine the effect of blood lipid levels on AVNFH development. Inclusion and exclusion criteria were predetermined to focus on isolated freshly closed femoral neck fractures in the elderly population. The primary outcome was the blood lipid levels. The secondary outcome was the logistic multi-factor regression analysis. A total of 325 elderly patients with low-energy femoral neck fractures (AVNFH, n = 160; control, n = 165) were assessed. In the AVNFH group, the average TC, TG, LDL, and Apo-B values were 7.11 ± 3.16 mmol/L, 2.15 ± 0.89 mmol/L, 4.49 ± 1.38 mmol/L, and 79.69 ± 17.29 mg/dL, respectively; all of which were significantly higher than the values in the control group. Logistic multi-factor regression analysis showed that both TC and LDL were the independent factors influencing the postoperative AVNFH within femoral neck fractures. This evidence indicates that AVNFH was significantly associated with blood lipid abnormalities in elderly patients with low-energy femoral neck fractures. The findings of this pilot trial justify a larger study to determine whether the result is more generally applicable to a broader population.

Vascularized fibular epiphyseal transfer for proximal humeral reconstruction in children with a primary sarcoma of bone.

PubMed

Stevenson, J D; Doxey, R; Abudu, A; Parry, M; Evans, S; Peart, F; Jeys, L

2018-04-01

Aims Preserving growth following limb-salvage surgery of the upper limb in children remains a challenge. Vascularized autografts may provide rapid biological incorporation with the potential for growth and longevity. In this study, we aimed to describe the outcomes following proximal humeral reconstruction with a vascularized fibular epiphyseal transfer in children with a primary sarcoma of bone. We also aimed to quantify the hypertrophy of the graft and the annual growth, and to determine the functional outcomes of the neoglenofibular joint. Patients and Methods We retrospectively analyzed 11 patients who underwent this procedure for a primary bone tumour of the proximal humerus between 2004 and 2015. Six had Ewing's sarcoma and five had osteosarcoma. Their mean age at the time of surgery was five years (two to eight). The mean follow-up was 5.2 years (1 to 12.2). Results The overall survival at five and ten years was 91% (confidence interval (CI) 95% 75% to 100%). At the time of the final review, ten patients were alive. One with local recurrence and metastasis died one-year post-operatively. Complications included seven fractures, four transient nerve palsies, and two patients developed avascular necrosis of the graft. All the fractures presented within the first postoperative year and united with conservative management. One patient had two further operations for a slipped fibular epiphysis of the autograft, and a hemi-epiphysiodesis for lateral tibial physeal arrest. Hypertrophy and axial growth were evident in nine patients who did not have avascular necrosis of the graft. The mean hypertrophy index was 65% (55% to 82%), and the mean growth was 4.6 mm per annum (2.4 to 7.6) in these nine grafts. At final follow-up, the mean modified functional Musculoskeletal Tumour Society score was 77% (63% to 83%) and the mean Toronto Extremity Salvage Score (TESS) was 84% (65% to 94%). Conclusion Vascularized fibular epiphyseal transfer preserves function and growth in young children following excision of the proximal humerus for a malignant bone tumour. Function compares favourably to other limb-salvage procedures in children. Longer term analysis is required to determine if this technique proves to be durable into adulthood. Cite this article: Bone Joint J 2018;100-B:535-41.

A microcomputer system for on-line study of atrioventricular node accommodation.

PubMed

Jenkins, J R; Clemo, H F; Belardinelli, L

1987-11-01

An automated on-line programmable stimulator and interval measurement system was developed to study atrioventricular node (AVN) accommodation. This dedicated microcomputer system measures and stores the stimulus-to-His bundle (S-H) interval from His bundle electrogram (HBE) recordings. Interval measurements for each beat are accurate to within 500 microsecond. This user-controlled system has been used to stimulate at any rate up to 6.5 Hz and to measure intervals up to 125 ms in isolated perfused guinea pig hearts. A built-in timer-reset mechanism prevents failure of the system in the absence of a His potential (i.e., 2:1 AV block). It may be modified for use in clinical studies or other experimental systems and has the ability to measure other physiological intervals. The system provides the precision in pacing and accuracy in the measurement of AVN conduction time that is necessary for meaningful analysis of AVN accommodation and has the simplicity of design and use that is not available in previously described systems. Furthermore, this computer system can be used not only in studies involving AV conduction, but also in any setting where programmed stimulation and interval measurement and recording need to be performed simultaneously.

Healing potential of transplanted allogeneic chondrocytes of three different sources in lesions of the avascular zone of the meniscus: a pilot study.

PubMed

Weinand, Christian; Peretti, Giuseppe M; Adams, Samuel B; Randolph, Mark A; Savvidis, Estafios; Gill, Thomas J

2006-11-01

Successful treatment of tears to the avascular region of the meniscus remains a challenge. Current repair techniques, such as sutures and anchors, are effective in stabilizing the peripheral, vascularized regions of the meniscus, but are not adequate for promoting healing in the avascular region. The purpose of this study was to demonstrate the healing ability of a tissue-engineered repair technique using allogenic chondrocytes from three different sources for the avascular zone of the meniscus. Articular, auricular, and costal chondrocytes were harvested from 3-month-old Yorkshire swine. A 1-cm bucket-handle lesion was created in the avascular zone of each three swine. A cell-scaffold construct, composed of a single chondrocyte cell type and Vicryl mesh, was implanted into the lesion and secured with two vertical mattress sutures. Controls consisted of each three sutured unseeded mesh implants, suture only, and untreated lesions. The swine were allowed immediate post-operative full weight bearing. Menisci and controls were harvested after 12 weeks. In all experimental samples, lesion closure was observed. Gross mechanical testing with two Adson forceps demonstrated bonding of the lesion. Histological analysis showed formation of new tissue in all three experimental samples. None of the control samples demonstrated closure and formation of new matrix. We present preliminary data that demonstrates the potential of a tissue-engineered, allogenic cellular repair to provide successful healing of lesions in the avascular zone in a large animal model.

Gene Electrotransfer of Plasmid with Tissue Specific Promoter Encoding shRNA against Endoglin Exerts Antitumor Efficacy against Murine TS/A Tumors by Vascular Targeted Effects.

PubMed

Stimac, Monika; Dolinsek, Tanja; Lampreht, Ursa; Cemazar, Maja; Sersa, Gregor

2015-01-01

Vascular targeted therapies, targeting specific endothelial cell markers, are promising approaches for the treatment of cancer. One of the targets is endoglin, transforming growth factor-β (TGF-β) co-receptor, which mediates proliferation, differentiation and migration of endothelial cells forming neovasculature. However, its specific, safe and long-lasting targeting remains the challenge. Therefore, in our study we evaluated the transfection efficacy, vascular targeted effects and therapeutic potential of the plasmid silencing endoglin with the tissue specific promoter, specific for endothelial cells marker endothelin-1 (ET) (TS plasmid), in comparison to the plasmid with constitutive promoter (CON plasmid), in vitro and in vivo. Tissue specificity of TS plasmid was demonstrated in vitro on several cell lines, and its antiangiogenic efficacy was demonstrated by reducing tube formation of 2H11 endothelial cells. In vivo, on a murine mammary TS/A tumor model, we demonstrated good antitumor effect of gene electrotransfer (GET) of either of both plasmids in treatment of smaller tumors still in avascular phase of growth, as well as on bigger tumors, already well vascularized. In support to the observations on predominantly vascular targeted effects of endoglin, histological analysis has demonstrated an increase in necrosis and a decrease in the number of blood vessels in therapeutic groups. A significant antitumor effect was observed in tumors in avascular and vascular phase of growth, possibly due to both, the antiangiogenic and the vascular disrupting effect. Furthermore, the study indicates on the potential use of TS plasmid in cancer gene therapy since the same efficacy as of CON plasmid was determined.

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

PubMed

Yin, Han; Yuan, Zhenfeng; Wang, Dawei

2016-08-15

Multiple small drilling for core decompression is widely used to preserve the femoral head in patients with avascular necrosis of the femoral head (ANFH). Nevertheless, the clinical outcome remains controversial. Simvastatin has been demonstrated to promote bone formation and reduce bone adsorption. The purpose of this study was to determine whether simvastatin enhanced the effect of multiple decompressions in preventing progression of ANFH and to identify independent risk factors associated with poor results. We retrospectively analyzed 58 hips in 36 patients, with a follow-up of 36 months. 20 patients (32 hips) underwent multiple drilling combined with simvastatin treatment (SIM group); 16 patients (26 hips) underwent multiple drilling alone (MD group). We defined clinical failure as a requirement for subsequent hip surgery or Harris Hip Score < 75. New occurrence of collapse or increased collapse > 2 mm on plain radiographs was defined as radiological failure. Successful clinical results were achieved in 27 of 32 hips (84 %) in the SIM group compared with 15 of 26 hips (58 %) in the MD group (OR = 0.2, CI (0.1, 0.6.), P = 0.032). Successful radiological results were achieved in 27 of 32 hips (84 %) in the SIM group and in 16 of 26 hips (61.5 %) in the MD group (P = 0.048). Body mass index, disease stage and location of lesion were independent prognostic factors for overall survival. We believe that simvastatin could enhance the effects of multiple decompressions in preventing progression of ANFH and reducing the risk of femoral head collapse.

Treatment of sickle cell disease's hip necrosis by core decompression: a prospective case-control study.

PubMed

Mukisi-Mukaza, M; Manicom, O; Alexis, C; Bashoun, K; Donkerwolcke, M; Burny, F

2009-11-01

The young age of patients, total arthroplasties complications risks, and implant costs justify evaluation of the results of core decompression in the treatment of sickle-cell disease avascular necrosis of the femoral head (ONFH). In sickle-cell disease necrosis, core decompression offers good relief from pain and delays the use of total arthroplasty in comparison to a conservatively treated control group by a simple non-weight bearing protocol. From 1994 to 2008, among 215 drepanocytic adults, 42 patients (22 genotype SS, 20 genotype SC; 15 men, 27 women) presented symptomatic ONFH. We report the data from a prospective study of two patients' groups: a non-operated group (16 patients aged 36.5+/-6.5 years, 23 hips) and an operated group (26 patients aged 30.3+/-2.8 years, 42 hips). The results were considered on the basis of change in clinical status according to the numeric evaluation of pain scale, the functional score of Merle d'Aubigné-Postel (MAP), the radiological progression of lesions, and the time delay to total arthroplasty. Twenty-three hips were conservatively treated by discharge (a pair of canes). After a follow-up period of 13.4+/-0.5 years, no pain improvement was noted (p=0.76), and MAP score was unchanged (p=0.27). Out of 23 hips managed by discharge, 9 stage IV hips (degenerative arthritis, 39.1%) underwent arthroplasty after an average delay of 2.6+/-2.4 years. Forty-two hips were treated by core decompression. The duration of follow-up was 11.3+/-1.8 years. Postoperatively, pain reduction and MAP score improvement were significant in 39 out of 42 hips (93%, p<0.0001). Twenty-nine out of these 42 hips had a favorable evolution. Ten hips (23.8%) progressed to total arthroplasty, after a period of 7.4+/-2.7 years, longer than the one of the non-operated group (p=0.0007). By comparing the two groups (operated and non-operated), the benefit of core decompression appeared very significant (p<0.0001). In addition to allocating patients osteonecrosis stages, the Koo and Kim Index estimated the severity and evolution of necrotic lesions in both groups. It indicated decline in the non-operated group (p=0.002) and improvement for operated patients (p=0.0002). Core decompression had a favorable clinical and radiological outcome superior to surgical abstention. Stages I and II ONFH remained stable after drilling, necessitating no arthroplasty (considered as a failure of drilling). The Koo and Kim Index above 30 degrees in the non-operated group was a significant indicator of lesions degradation (p=0.002). In addition to the indolence obtained by core decompression, the benefit of drilling was manifested by the prolonging the adjournment before arthroplasty end-point. It was respectively 7.4+/-2.7 years in the operated group versus 2.6+/-2.4 years in the non-operated group (difference of 4.8 years, p<0.01). The technique of core decompression remains a valid option place in the treatment sickle-cell disease avascular necrosis of the femoral head (ONFH). It may be especially recommended in under-equipped regions where drepanocytosis and its osteo-articular complications are frequent. Level III case-control therapeutic study. 2009 Published by Elsevier Masson SAS.

Holographic Optical Coherence Imaging of Rat Osteogenic Sarcoma Tumor Spheroids

NASA Astrophysics Data System (ADS)

Yu, Ping; Mustata, Mirela; Peng, Leilei; Turek, John J.; Melloch, Michael R.; French, Paul M. W.; Nolte, David D.

2004-09-01

Holographic optical coherence imaging is a full-frame variant of coherence-domain imaging. An optoelectronic semiconductor holographic film functions as a coherence filter placed before a conventional digital video camera that passes coherent (structure-bearing) light to the camera during holographic readout while preferentially rejecting scattered light. The data are acquired as a succession of en face images at increasing depth inside the sample in a fly-through acquisition. The samples of living tissue were rat osteogenic sarcoma multicellular tumor spheroids that were grown from a single osteoblast cell line in a bioreactor. Tumor spheroids are nearly spherical and have radial symmetry, presenting a simple geometry for analysis. The tumors investigated ranged in diameter from several hundred micrometers to over 1 mm. Holographic features from the tumors were observed in reflection to depths of 500-600 µm with a total tissue path length of approximately 14 mean free paths. The volumetric data from the tumor spheroids reveal heterogeneous structure, presumably caused by necrosis and microcalcifications characteristic of some human avascular tumors.

Modular femoral component for conversion of previous hip surgery in total hip arthroplasty.

PubMed

Goldstein, Wayne M; Branson, Jill J

2005-09-01

The conversion of previous hip surgery to total hip arthroplasty creates a durable construct that is anatomically accurate. Most femoral components with either cemented or cementless design have a fixed tapered proximal shape. The proximal femoral anatomy is changed due to previous hip surgery for fixation of an intertrochanteric hip fracture, proximal femoral osteotomy, or a fibular allograft for avascular necrosis. The modular S-ROM (DePuy Orthopaedics Inc., Warsaw, Ind) hip stem accommodates these issues and independently prepares the proximal and distal portion of the femur. In preparation and implantation, the S-ROM hip stem creates less hoop stresses on potentially fragile stress risers from screws and thin bone. The S-ROM hip stem also prepares a previously distorted anatomy by milling through cortical bone that can occlude the femoral medullar canals and recreate proper femoral anteversion and reduces the risk of intraoperative or postoperative periprosthetic fracture due to the flexible titanium-slotted stem. The S-ROM femoral stem is recommended for challenging total hip reconstructions.

[Stress analysis on the acetabular side of bipolar hemiarthroplasty by the two-dimensional finite element method incorporating the boundary friction layer].

PubMed

Ichihashi, K; Imura, S; Oomori, H; Gesso, H

1994-11-01

We compared the biomechanical characteristics of bipolar and unipolar hemiarthroplasty on the proximal migration of the outer head by determining the von Mises stress distribution and acetabular (outer head) displacement with clinical assessment of hemiarthroplasty in 75 patients. This analysis used the two-dimensional finite element method, which incorporated boundary friction layers on both the inner and outer bearings of the prosthesis. Acetabular reaming increased stress within the pelvic bone and migration of the outer head. A combination of the acetabular reaming and bone transplantation increased the stress within the pelvic bone and grafted bone, and caused outer head migration. These findings were supported by clinical results. Although the bipolar endoprosthesis was biomechanically superior to the unipolar endoprosthesis, migration of the outer head still occurred. The bipolar endoprosthesis appeared to be indicated in cases of a femoral neck fracture or of avascular necrosis in the femoral head, but its use in cases of osteoarthritis in the hip required caution.

Corneal avascularity is due to soluble VEGF receptor-1

PubMed Central

Ambati, Balamurali K.; Nozaki, Miho; Singh, Nirbhai; Takeda, Atsunobu; Jani, Pooja D.; Suthar, Tushar; Albuquerque, Romulo J. C.; Richter, Elizabeth; Sakurai, Eiji; Newcomb, Michael T.; Kleinman, Mark E.; Caldwell, Ruth B.; Lin, Qing; Ogura, Yuichiro; Orecchia, Angela; Samuelson, Don A.; Agnew, Dalen W.; Leger, Judy St.; Green, W. Richard; Mahasreshti, Parameshwar J.; Curiel, David T.; Kwan, Donna; Marsh, Helene; Ikeda, Sakae; Leiper, Lucy J.; Collinson, J. Martin; Bogdanovich, Sasha; Khurana, Tejvir S.; Shibuya, Masabumi; Baldwin, Megan E.; Ferrara, Napoleone; Gerber, Hans-Peter; Falco, Sandro De; Witta, Jassir; Baffi, Judit Z.; Raisler, Brian J.; Ambati, Jayakrishna

2009-01-01

Corneal avascularity—the absence of blood vessels in the cornea—is required for optical clarity and optimal vision, and has led to the cornea being widely used for validating pro- and anti-angiogenic therapeutic strategies for many disorders1-4. But the molecular underpinnings of the avascular phenotype have until now remained obscure5-10 and are all the more remarkable given the presence in the cornea of vascular endothelial growth factor (VEGF)-A, a potent stimulator of angiogenesis, and the proximity of the cornea to vascularized tissues. Here we show that the cornea expresses soluble VEGF receptor-1 (sVEGFR-1; also known as sflt-1) and that suppression of this endogenous VEGF-A trap11 by neutralizing antibodies, RNA interference or Cre-lox-mediated gene disruption abolishes corneal avascularity in mice. The spontaneously vascularized corneas of corn1 and Pax6+/− mice12,13 and Pax6+/− patients with aniridia14 are deficient in sflt-1, and recombinant sflt-1 administration restores corneal avascularity in corn1 and Pax6+/− mice. Manatees, the only known creatures uniformly to have vascularized corneas15, do not express sflt-1, whereas the avascular corneas of dugongs, also members of the order Sirenia, elephants, the closest extant terrestrial phylogenetic relatives of manatees, and other marine mammals (dolphins and whales) contain sflt-1, indicating that it has a crucial, evolutionarily conserved role. The recognition that sflt-1 is essential for preserving the avascular ambit of the cornea can rationally guide its use as a platform for angiogenic modulators, supports its use in treating neovascular diseases, and might provide insight into the immunological privilege of the cornea. PMID:17051153

Stem cell-based tissue-engineering for treatment of meniscal tears in the avascular zone.

PubMed

Zellner, Johannes; Hierl, Katja; Mueller, Michael; Pfeifer, Christian; Berner, Arne; Dienstknecht, Thomas; Krutsch, Werner; Geis, Sebastian; Gehmert, Sebastian; Kujat, Richard; Dendorfer, Sebastian; Prantl, Lukas; Nerlich, Michael; Angele, Peter

2013-10-01

Meniscal tears in the avascular zone have a poor self-healing potential, however partial meniscectomy predisposes the knee for early osteoarthritis. Tissue engineering with mesenchymal stem cells and a hyaluronan collagen based scaffold is a promising approach to repair meniscal tears in the avascular zone. 4 mm longitudinal meniscal tears in the avascular zone of lateral menisci of New Zealand White Rabbits were performed. The defect was left empty, sutured with a 5-0 suture or filled with a hyaluronan/collagen composite matrix without cells, with platelet rich plasma or with autologous mesenchymal stem cells. Matrices with stem cells were in part precultured in chondrogenic medium for 14 days prior to the implantation. Menisci were harvested at 6 and 12 weeks. The developed repair tissue was analyzed macroscopically, histologically and biomechanically. Untreated defects, defects treated with suture alone, with cell-free or with platelet rich plasma seeded implants showed a muted fibrous healing response. The implantation of stem cell-matrix constructs initiated fibrocartilage-like repair tissue, with better integration and biomechanical properties in the precultured stem cell-matrix group. A hyaluronan-collagen based composite scaffold seeded with mesenchymal stem cells is more effective in the repair avascular meniscal tear with stable meniscus-like tissue and to restore the native meniscus. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

To Screen or Not to Screen? A Decision Analysis of the Utility of Screening for Developmental Dysplasia of the Hip

PubMed Central

Mahan, Susan T.; Katz, Jeffrey N.; Kim, Young-Jo

2009-01-01

Background: The United States Preventive Services Task Force recently determined that they could not recommend any screening strategies for developmental dysplasia of the hip. Disparate findings in the literature and treatment-related problems have led to confusion about whether or not to screen for this disorder. The purpose of the present study was to determine, with use of expected-value decision analysis, which of the following three strategies leads to the best chance of having a non-arthritic hip by the age of sixty years: (1) no screening for developmental dysplasia of the hip, (2) universal screening of newborns with both physical examination and ultrasonography, or (3) universal screening with physical examination but only selective use of ultrasonography for neonates considered to be at high risk. Methods: Developmental dysplasia of the hip, avascular necrosis, and the treatment algorithm were carefully defined. The outcome was determined as the probability of any neonate having a non-arthritic hip through the age of sixty years. A decision tree was then built with decision nodes as described above, and chance node probabilities were determined from a thorough review of the literature. Foldback analysis and sensitivity analyses were performed. Results: The expected value of a favorable hip outcome was 0.9590 for the strategy of screening all neonates with physical examination and selective use of ultrasonography, 0.9586 for screening all neonates with physical examination and ultrasonography, and 0.9578 for no screening. A lower expected value implies a greater risk for the development of osteoarthritis as a result of developmental dysplasia of the hip or avascular necrosis; thus, the optimum strategy was selective screening. This model was robust to sensitivity analysis, except when the rate of missed dysplasia rose as high as 4/1000 or the rate of treated hip subluxation/dislocation was the same; then, the optimum strategy was to screen all neonates with both physical examination and ultrasonography. Conclusions: Our decision analytic model indicated that the optimum strategy, associated with the highest probability of having a non-arthritic hip at the age of sixty years, was to screen all neonates for hip dysplasia with a physical examination and to use ultrasonography selectively for infants who are at high risk. Additional data on the costs and cost-effectiveness of these screening policies are needed to guide policy recommendations. Level of Evidence: Economic and decision analysis Level II. See Instructions to Authors for a complete description of levels of evidence. PMID:19571094

Intrauterine growth restriction in infants of less than thirty-two weeks' gestation: associated placental pathologic features.

PubMed

Salafia, C M; Minior, V K; Pezzullo, J C; Popek, E J; Rosenkrantz, T S; Vintzileos, A M

1995-10-01

Our purpose was to describe placental lesions associated with normal and abnormal fetal growth in infants delivered for obstetric indications at < 32 weeks' gestation. Maternal and neonatal charts and placental tissues from 420 consecutive nonanomalous live-born singleton infants delivered at < 32 weeks' gestation with accurate gestational dates were retrospectively studied. Excluded were cases with maternal diabetes, chronic hypertension, hydrops fetalis, diagnosed congenital viral infection, and placenta previa, leaving four primary indications for delivery: preeclampsia, preterm labor, premature rupture of membranes, and nonhypertensive abruptio placentae. The presence and severity of placental lesions was scored by a pathologist blinded to clinical data. Birth weight and length percentiles were calculated from published nomograms. Asymmetric intrauterine growth retardation (n = 32) was defined as birth weight < 10th percentile with length > 10th percentile and symmetric intrauterine growth retardation (n = 48) as both weight and length < 10th percentile for gestational age. A "growth restriction index" was developed to express a continuum of growth in both length and weight. Contingency tables, analyses of variance, and multiple regression analysis defined significance as p < 0.05 (with corrections for multiple comparisons). A greater proportion of cases with intrauterine growth retardation had lesions of uteroplacental insufficiency (p < 0.001) or chronic villitis (p < 0.02) than did appropriately grown preterm infants. Cases with asymmetric intrauterine growth retardation tended to have more lesions than did cases with appropriate-for-gestational-age infants. Four multiple regression analyses used the growth restriction index as outcome and the histologic lesion that had significant relationships to fetal growth as independent predictors in univariate analyses. Overall, uteroplacental fibrinoid necrosis, circulating nucleated erythrocytes, avascular terminal villi, and villous infarct were significant independent predictors of fetal growth (adjusted R2 = 0.312). With addition of preeclampsia as a variable, villous fibrosis, avascular villi, infarct, and preeclampsia were independent predictors of fetal growth (adjusted R2 = 0.341). In the 65 preeclampsia cases no histologic lesion was an independent predictor of fetal growth, whereas in the nonpreeclampsia cases, villous fibrosis and avascular villi were independent predictors of fetal growth (adjusted R2 = 0.075). In nonanomalous preterm infants intrauterine growth retardation is most commonly symmetric and is primarily related to the cumulative number and severity of lesions reflecting abnormal uteroplacental or fetoplacental blood flow. The growth restriction index may contribute to the study of the biologic range of fetal growth. The statistical relationship of most placental lesions to intrauterine growth retardation depends on the presence or absence of preeclampsia.

Peripheral Avascular Retina in a Term Male Neonate With Microvillus Inclusion Disease and Pancreatic Insufficiency.

PubMed

Paulus, Yannis M; Alcorn, Deborah M; Gaynon, Michael; Moshfeghi, Darius M

2015-05-01

The authors present the first case of peripheral avascular retina in a term male neonate with pancreatic exocrine insufficiency, atypical microvillus inclusion disease, flat tympanograms, and recurrent urinary tract infections. Clinical examination showed avascular peripheral retina to posterior zone II temporally, with a flat stage 1-like demarcation line, and no plus disease. Genetic testing results were normal. The patient developed peripheral neovascularization and underwent panretinal photocoagulation. This case likely represents mild Norrie disease, familial exudative vitreoretinopathy, or incontinentia pigmenti due to a Wnt signaling abnormality. While these conditions are usually more severe, a variable spectrum of Wnt abnormalities exists throughout the body. Copyright 2015, SLACK Incorporated.

Histological Comparison of Kidney Tissue Following Radioembolization with Yttrium-90 Resin Microspheres and Embolization with Bland Microspheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silva, Suresh de, E-mail: suresh.desilva@unsw.edu.au; Mackie, Simon; Aslan, Peter

BackgroundIntra-arterial brachytherapy with yttrium-90 ({sup 90}Y) resin microspheres (radioembolization) is a procedure to selectively deliver high-dose radiation to tumors. The purpose of this research was to compare the radioembolic effect of {sup 90}Y-radioembolization versus the embolic effect of bland microspheres in the porcine kidney model.MethodsIn each of six pigs, ~25–33 % of the kidney volume was embolized with {sup 90}Y resin microspheres and an equivalent number of bland microspheres in the contralateral kidney. Kidney volume was estimated visually from contrast-enhanced fluoroscopy imaging. Morphologic and histologic analysis was performed 8–9 weeks after the procedure to assess the locations of the microspheres and extentmore » of tissue necrosis from {sup 90}Y-radioembolization and bland embolization. A semi-quantified evaluation of the non-acute peri-particle and perivascular tissue reaction was conducted. All guidelines for the care and use of animals were followed.ResultsKidneys embolized with {sup 90}Y-radioembolization decreased in mass by 30–70 % versus the contralateral kidney embolized with bland microspheres. These kidneys showed significant necrosis/fibrosis, avascularization, and glomerular atrophy in the immediate vicinity of the {sup 90}Y resin microspheres. By contrast, glomerular changes were not observed, even with clusters of bland microspheres in afferent arterioles. Evidence of a foreign body reaction was recorded in some kidneys with bland microspheres, and subcapsular scarring/infarction only with the highest load (4.96 × 10{sup 6}) of bland microspheres.ConclusionThis study showed that radioembolization with {sup 90}Y resin microspheres produces localized necrosis/fibrosis and loss of kidney mass in a porcine kidney model. This result supports the study of {sup 90}Y resin microspheres for the localized treatment of kidney tumors.« less

Morphological study of the atrioventricular conduction system and Purkinje fibers in yak.

PubMed

Duan, Deyong; Yu, Sijiu; Cui, Yan; Li, Chaoxu

2017-07-01

We studied the morphology of the atrioventricular conduction system (AVCS) and Purkinje fibers of the yak. Light and transmission electron microscopy were used to study the histological features of AVCS. The distributional characteristics of the His-bundle, the left bundle branch (LBB), right bundle branch (RBB), and Purkinje fiber network of yak hearts were examined using gross dissection, ink injection, and ABS casting. The results showed that the atrioventricular node (AVN) of yak located in the right side of interatrial septum and had a flattened ovoid shape. The AVN of yak is composed of the slender, interweaving cells formed almost entirely of the transitional cells (T-cells). The His-bundle extended from the AVN, and split into left LBB and RBB at the crest of the interventricular septum. The LBB descended along the left side of interventricular septum. At approximately the upper 1/3 of the interventricular septum, the LBB typically divided into three branches. The RBB ran under the endocardium of the right side of interventricular septum, and extended to the base of septal papillary muscle, passed into the moderator band, crossed the right ventricular cavity to reach the base of anterior papillary muscle, and divided into four fascicles under the subendocardial layer. The Purkinje fibers in the ventricle formed a complex spatial network. The distributional and cellular component characteristics of the AVCS and Purkinje fibers ensured normal cardiac function. © 2017 Wiley Periodicals, Inc.

Biological Strategies to Enhance Healing of the Avascular Area of the Meniscus

PubMed Central

Longo, Umile Giuseppe; Campi, Stefano; Romeo, Giovanni; Spiezia, Filippo; Maffulli, Nicola; Denaro, Vincenzo

2012-01-01

Meniscal injuries in the vascularized peripheral part of the meniscus have a better healing potential than tears in the central avascular zone because meniscal healing principally depends on its vascular supply. Several biological strategies have been proposed to enhance healing of the avascular area of the meniscus: abrasion therapy, fibrin clot, organ culture, cell therapy, and applications of growth factors. However, data are too heterogeneous to achieve definitive conclusions on the use of these techniques for routine management of meniscal lesions. Although most preclinical and clinical studies are very promising, they are still at an experimental stage. More prospective randomised controlled trials are needed to compare the different techniques for clinical results, applicability, and cost-effectiveness. PMID:22220179

[Palmar lunate dislocation].

PubMed

Isenberg, J; Prokop, A; Schellhammer, F; Helling, H J

2002-12-01

Palmar lunate dislocation as the end stage of a perilunate dislocation is a very uncommon injury. Having treated 19,534 hospitalized patients between 1 January 1986 and 1 October 2001 the diagnosis was recorded in four male trauma patients (33, 36, 37 and 62 years old). Among the operatively treated carpal dislocations and carpal fracture dislocations those of the lunate were seen in five per cent. The dislocation was caused in by an acute hyperextension injury resulting of falls from heights in three cases, and of a motorcycle accident in a further case. In two of these cases a complete palmar lunate dislocation was analysed that were produced by fall from seven meters heights of a young craftsman and by accident of a motorcyclist. First using a longitudinal palmar approach in both cases a revision of the hemorrhagic carpal canal was performed urgently, the largely denuded lunate was reduced and the repair of identified ligamentous structures was performed by means of sutures respectively suture anchors. Reduction was stabilized with Kirschner wires. Afterwards performed computed tomography identified the result of reduction and associated defects (subluxation distal radioulnar joint). In one patient a soft tissue infection prevented the dorsal ligamentous repair. In spite of a consequent after-treatment and a good functional result a scapho-lunate dissociation was proved. An avascular defect of the lunate could be excluded by magnetic resonance imaging. In case of a secondary performed dorsal repair a persisting carpal stabilization with a satisfactory functional result could achieved. At second hand an advanced carpal collapse was proved. If reduction cannot be achieved by closed manipulation or a loss of reduction is shown, open reduction is indicated first by a palmar approach. An additional dorsal ligamentous repair seems to be necessary. Transfixation by Kirschner wires and suture anchors stabilize the restored anatomic relationships. Wrist immobilization in a cast for at least eight weeks is recommended. Although ligamentous insufficiency, osteoarthrosis and avascular necrosis are often proved, functional results are satisfactory.

Bone transport osteogenesis for reconstruction of a bone defect in the tibiotarsus of a yellow-naped Amazon parrot (Amazona ochrocephala auropalliata).

PubMed

Johnston, Matthew S; Thode, Henry P; Ehrhart, Nicole P

2008-03-01

A yellow-naped Amazon parrot (Amazona ochrocephala auropalliata) was presented 5 months after a traumatic fracture of its left tibiotarsus. Fixation of the simple, closed, mid-diaphyseal fracture was originally with an intramedullary pin and external coaptation with a modified Robert-Jones bandage. During the subsequent 5 months, the bone became osteopenic, and the middle third of the tibiotarsus exhibited probable avascular necrosis. After various fixation attempts failed, the parrot was fitted with a ring fixator device, and bone transport osteogenesis was attempted. Within 7 weeks, the left tibiotarsus had regrown to full length, but the docking site at the proximal fracture line had not healed. After 2 more surgeries to debride bone ends to stimulate healing, the leg in this parrot became functional. This is the first reported clinical use of bone transport osteogenesis in a pet bird. Materials and techniques were applied successfully to this parrot, which suggests that bone transport osteogenesis deserves further study for the repair of large bone defects in birds.

Shaft-Condylar Angle for surgical correction in neglected and displaced lateral humeral condyle fracture in children.

PubMed

Mulpruek, Pornchai; Angsanuntsukh, Chanika; Woratanarat, Patarawan; Sa-Ngasoongsong, Paphon; Tawonsawatruk, Tulyapruek; Chanplakorn, Pongsthorn

2015-09-01

To assess the outcome after using the Shaft-Condylar angle (SCA) as intraoperative reference for sagittal plane correction in displaced lateral humeral condyle fractures in children presented 3-weeks after injury. Ten children, with delayed presentation of a displaced lateral humeral condyle fracture and undergoing surgery during 1999-2011, were reviewed. The goal was to obtain a smooth articular surface with an intraoperative SCA of nearly 40° and nearest-anatomical carrying angle. They were allocated into two groups according to the postoperative SCA [Good-reduction group (SCA=30-50°), and Bad-reduction group (SCA<30°, >50°)] and the final outcomes were then compared. All fractures united without avascular necrosis. The Good-reduction group (n=7) showed a significant improvement in final range of motion and functional outcome compared to the Bad-reduction group (n=3) (p=0.02). However, there was no significant difference in pain, carrying angle and overall outcome between both groups. SCA is a possible intraoperative reference for sagittal alignment correction in late presented displaced lateral humeral condyle fractures.

Magnetic resonance imaging of the wrist: bone and cartilage injury.

PubMed

Hayter, Catherine L; Gold, Stephanie L; Potter, Hollis G

2013-05-01

Magnetic resonance imaging (MRI) is particularly useful for imaging the wrist due to its superior soft tissue contrast and ability to detect subtle bone marrow changes and occult fractures. A high field (1.5T or greater) strength, dedicated wrist coil, and high in-plane and through-plane resolution must be utilized to successfully visualize the relatively thin cartilage of the wrist. MRI can be used to detect occult carpal bone fractures, identify complications following scaphoid fractures, and assess for avascular necrosis in the setting in Kienböck's and Preiser's disease. MRI is useful to identify secondary soft tissue and chondral pathology in impaction/impingement syndromes. The use of an intermediate-echo time fast spin echo sequence allows for accurate assessment of articular cartilage, allowing evaluation of chondral wear in the setting of primary osteoarthritis and posttraumatic degenerative arthrosis. MRI is the most sensitive imaging modality for the detection of early inflammatory arthropathies and can detect synovitis, bone marrow edema, and early erosions in the setting of negative radiographs. Copyright © 2012 Wiley Periodicals, Inc.

A new internal fixation technique for fractures of the proximal humerus--the Bilboquet device: a report on 26 cases.

PubMed

Doursounian, L; Grimberg, J; Cazeau, C; Jos, E; Touzard, R C

2000-01-01

We describe a novel internal fixation device and report on 26 patients (mean age, 70 years) whose proximal humeral fractures were managed with this technique. The 2-part titanium implant consists of a circular staple impacted into the humeral head cancellous bone and a spigoted diaphyseal stem that inserts into the staple "cup." Of the 26 cases reviewed, 16 had 3-part fractures and 10 had 4-part fractures. Mean follow-up was 25.9 months. In the 16 3-part fractures, the mean active forward elevation was 114 degrees and the results were as follows: excellent, 7; good, 5; fair, 3; poor, 1. In the 10 4-part fracture patients, the mean active forward elevation was 101 degrees and the results were as follows: excellent, 2; good, 4; fair, 3; poor, 1. There were 5 cases of avascular necrosis and 1 case of tuberosity nonunion. Only 2 cases needed conversion to hemiarthroplasty. The new technique should simplify the surgery of these fractures and reduce the need for arthroplasty.

Ipsilateral hip and knee dislocation: Case report and review of literature

PubMed Central

Sharma, Gaurav; Chahar, Deepak; Sreenivasan, Ravi; Verma, Nikhil; Pankaj, Amite

2016-01-01

Hip and knee dislocations are not uncommon but simultaneous ipsilateral dislocation of the hip and knee joint is rare; consequently, there is an inadequate amount of literature on the subject. We identified only 11 such cases reported in English literature. In the present report, we describe the case of a 23-year-old male patient who presented with ipsilateral hip and knee dislocation on the right side after being involved in a road traffic accident. The hip dislocation was associated with a posterior wall acetabular fracture. The hip as well as the knee joints was reduced in the emergency bay. The patient underwent an urgent fixation of the posterior wall acetabular fracture with delayed ligament reconstruction for the knee dislocation. At one-year follow-up, he had no pain in the hip or knee. There was grade 1 posterior sag but no symptoms of knee instability. Radiographs revealed no evidence of avascular necrosis or arthritis of the femoral head. The normal treatment protocol for individual injury is affected by the simultaneous occurrence of hip and knee dislocation. PMID:27182149

Web-based Teaching Radio Interferometer for Africa

NASA Astrophysics Data System (ADS)

Carignan, Claude; Libert, Yannick

2016-10-01

This presentation describes the web-based Teaching Radio Interferometer being built on the campus of the University of Cape Town, in South Africa, to train the future users of the African VLBI (Very Long Baseline Interferometry) Network (AVN).

The structure and rainfall features of Tropical Cyclone Rammasun (2002)

NASA Astrophysics Data System (ADS)

Ma, Leiming; Duan, Yihong; Zhu, Yongti

2004-12-01

Tropical Rainfall Measuring Mission (TRMM) data [TRMM Microwave Imager/Precipitation Radar/Visible and Infrared Scanner (TMI/PR/VIRS)] and a numerical model are used to investigate the structure and rainfall features of Tropical Cyclone (TC) Rammasun (2002). Based on the analysis of TRMM data, which are diagnosed together with NCEP/AVN [Aviation (global model)] analysis data, some typical features of TC structure and rainfall are preliminary discovered. Since the limitations of TRMM data are considered for their time resolution and coverage, the world observed by TRMM at several moments cannot be taken as the representation of the whole period of the TC lifecycle, therefore the picture should be reproduced by a numerical model of high quality. To better understand the structure and rainfall features of TC Rammasun, a numerical simulation is carried out with mesoscale model MM5 in which the validations have been made with the data of TRMM and NCEP/AVN analysis.

An Overview of Geodetic and Astrometric VLBI at the Hartebeesthoek Radio Astronomy Observatory

NASA Astrophysics Data System (ADS)

de Witt, A.; Gaylard, M.; Quick, J.; Combrinck, L.

2013-08-01

For astronomical Very Long Baseline Interferometry (VLBI), the Hartebeesthoek Radio Astronomy Observatory (HartRAO), in South Africa operates as part of a number of networks including the European and Australian VLBI networks, global arrays and also space VLBI. HartRAO is the only African representative in the international geodetic VLBI network and participates in regular astrometric and geodetic VLBI programmes. HartRAO will play a major role in the realization of the next generation full-sky celestial reference frame, especially the improvement of the celestial reference frame in the South. The observatory also provides a base for developing the African VLBI Network (AVN), a project to convert redundant satellite Earth-station antennas across Africa to use for radio astronomy. The AVN would greatly facilitate VLBI observations of southern objects. We present an overview of the current capabilities as well as future opportunities for astrometric and geodetic VLBI at HartRAO.

Heparan sulfate storage in the cardiac conduction system triggers atrioventricular block.

PubMed

Kato, Rie; Miyahara, Hiroaki; Kawano, Tatsuya; Matsuzuka, Atsuko; Noda, Kimiko; Izumi, Tatsuro

2017-05-01

To elucidate the novel biological functions of heparan sulfate (HS) by clinic-pathologically studying a patient with paroxysmal atrioventricular (AV) block. A long-surviving male patient with Sanfilippo syndrome type A presented with paroxysmal AV block at age 33years. He then survived another 2.5years after the onset of paroxysmal AV block and pacemaker implantation. His cardiac histopathological examination at autopsy showed HS storage in the cardiac conduction system (CCS), especially in the atrioventricular node (AVN)-His bundle branches. HS storage in the CCS might trigger AV block, arising from below the AVN-His bundle branches. This is the first description to indicate that HS might be an essential constituent of life-long CCS plasticity and that its storage in the CCS results in AV block. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Experimentally gained insight - based proposal apropos the treatment of osteonecrosis of the femoral head.

PubMed

Boss, J H; Misselevich, I; Bejar, J; Norman, D; Zinman, C; Reis, D N

2004-01-01

An impeded blood flow through the femoral head is incriminated in the etiopathogenesis of osteonecrosis of the femoral head. The disorder is either primary (idiopathic avascular osteonecrosis) or secondary to one condition or another, say, corticosteroid medication, fracture of the neck, coagulation defects, physical or thermal damage, storage disorders, alcoholism, and infectious, autoimmune as also marrow infiltrating diseases. In the wake of the necrosis, several mediators are released in increased amounts, prime among which is the vascular endothelial growth factor. The intermediates recruit endothelial progenitor cells, macrophages, osteoclasts, fibroblasts, and osteoblasts, which, pervading throughout the necrotic areas, initiate the reparative processes. The dead, soft and hard tissular debris is substituted by fibrous - later on by hematopoietic-fatty tissue - and bone. The newly formed, appositional and intramembranous bone is deficient in its mechanical properties. The ordinary load-carrying functions suffice to deform these weakened femoral heads so that osteoarthritic changes develop. Considering contemporary assumptions of the causes of osteonecrosis, oxygenation, revascularization, and core decompression are the realistic therapeutic interventions. Necrosis of rats' femoral heads is studied as a model of osteonecrosis in both adults and children. In view of rodents' lifelong persisting physeal cartilage, vascular deprivation-induced osteonecrosis in rats mimics children's Perthes disease. The experimental model, which is well suited to test treatment modalities, has been used to investigate the effects of exposure to hyperbaric oxygen with and without non-weight bearing, medication of enoxaparin, and creation of an intraosseous conduit on the remodeling of the avascular necrotic femoral head. Intriguingly, the shape of treated rats' femoral heads is disfigured to a greater degree than that of untreated animals. This is most likely due to the reduced yield strength and elastic modulus as well as the raised strain-to-failure of the recently formed bone making up the post-necrotic femoral heads. It follows that expedited osteogenesis is, counter intuition, detrimental to maintaining the hemispherical shape of the femoral head, and thus to an articulation with congruent load-bearing surfaces. If this is indeed the case, the remodeling of the necrotic femoral head should be delayed, rather than sped up, as the present day paradigm would have it. Bearing in mind that the dead osseous structures keep their mechanical attributes for quite a while, a slowed down new bone formation would favor the gradual replacement of the necrotic by living bone. Therefore, management of the adult patients with osteonecrosis and children with Perthes disease should focus on a slowly progressive substitution so that the decline of the bone's mechanical properties is kept to a minimum. One viable therapeutic mode is a medication of inhibitors of the vascular endothelial growth factor.

A human factors evaluation of the operational demonstration flight inspection aircraft.

DOT National Transportation Integrated Search

1995-05-01

These reports describe the data collection and analysis efforts performed by the Civil Aerospace Medical Institute's Human Factors Research Laboratory to assist the Office of Aviation System Standards (AVN) in the human factors evaluation of the Oper...