448 research outputs found

    Sagittal realignment osteotomy for increased posterior tibial slope after opening-wedge high tibial osteotomy: a case report

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    A 40 year old welder who underwent opening-wedge high tibial osteotomy for correction of alignment in a varus knee developed persistent pain with loss of knee extension. The posterior tibial slope increased from 9 degrees to 20 degrees after the osteotomy and caused the anteromedial knee pain and limited extension. The patient then underwent a revision osteotomy using a closing wedge technique to correct tibial slope. The osteotomy was performed, first from the medial cortex in the lateral direction, and second in the anteroposterior direction to remove the tibial bone in wedge shape and obtain full extension of the knee. The posterior tibial slope decreased to 8 degrees after the revision osteotomy and the patients returned to pain-free daily life. We reviewed this unique technique for correction of sagittal malalignment using a closing-wedge osteotomy for revision after opening-wedge osteotomy

    Functional interface micromechanics of 11 en-bloc retrieved cemented femoral hip replacements

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    Contains fulltext : 88556.pdf (publisher's version ) (Open Access)BACKGROUND AND PURPOSE: Despite the longstanding use of micromotion as a measure of implant stability, direct measurement of the micromechanics of implant/bone interfaces from en bloc human retrievals has not been performed. The purpose of this study was to determine the stem-cement and cement-bone micromechanics of functionally loaded, en-bloc retrieved, cemented femoral hip components. METHODS: 11 fresh frozen proximal femurs with cemented implants were retrieved at autopsy. Specimens were sectioned transversely into 10-mm slabs and fixed to a loading device where functional torsional loads were applied to the stem. A digital image correlation technique was used to document micromotions at stem-cement and cement-bone interfaces during loading. RESULTS: There was a wide range of responses with stem-cement micromotions ranging from 0.0006 mm to 0.83 mm (mean 0.17 mm, SD 0.29) and cement-bone micromotions ranging from 0.0022 mm to 0.73 mm (mean 0.092 mm, SD 0.22). There was a strong (linear-log) inverse correlation between apposition fraction and micromotion at the stem-cement interface (r(2) = 0.71, p < 0.001). There was a strong inverse log-log correlation between apposition fraction at the cement-bone interface and micromotion (r(2) = 0.85, p < 0.001). Components that were radiographically well-fixed had a relatively narrow range of micromotions at the stem-cement (0.0006-0.057 mm) and cement-bone (0.0022-0.029 mm) interfaces. INTERPRETATION: Minimizing gaps at the stem-cement interface and encouraging bony apposition at the cement-bone interface would be clinically desirable. The cement-bone interface does not act as a bonded interface in actual use, even in radiographically well-fixed components. Rather, the interface is quite compliant, with sliding and opening motions between the cement and bone surfaces.1 juni 201

    Use of controlled low dose gamma irradiation to sterilize allograft tendons for ACL reconstruction: biomechanical and clinical perspective

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    As reviewed here, numerous biomechanical and clinical studies support the use of controlled, low temperature irradiation of allograft tendons, to provide both excellent clinical results and medical-device grade sterile allografts with minimal risk of disease transmission

    Inter-scan reproducibility of coronary calcium measurement using Multi Detector-Row Computed Tomography (MDCT)

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    Purpose: To assess inter-scan reproducibility of coronary calcium measurements obtained from Multi Detector-Row CT (MDCT) images and to evaluate whether this reproducibility is affected by different measurement protocols, slice thickness, cardiovascular risk factors and/or technical variables. Design: Cross-sectional study with repeated measurements. Materials and methods: The study population comprised 76 healthy women. Coronary calcium was assessed in these women twice in one session using 16-MDCT (Philips Mx 8000 IDT 16). Images were reconstructed with 1.5 mm slice thickness and 3.0 mm slice thickness. The 76 repeated scans were scored. The Agatston score, a volume measurement and a mass measurement were assessed. Reproducibility was determined by estimation of mean, absolute, relative difference, the weighted kappa value for agreement and the Intra-class correlation coefficient (ICCC). Results: Fifty-five participants (72.4%) had a coronary calcification of more than zero in Agatston (1.5 mm slice thickness). The reproducibility of coronary calcium measurements between scans in terms of ranking was excellent with Intra-class correlation coefficients of >0.98, and kappa values above 0.80. The absolute difference in calcium score between scans increased with increasing calcium levels, indicating that measurement error increases with increasing calcium levels. However, no relation was found between the mean difference in scores and calcium levels, indicating that the increase in measurement error is likely to result in random misclassification in calcium score. Reproducibility results were similar for 1.5 mm slices and for 3.0 mm slices, and equal for Agatston, volume and mass measurements. Conclusion: Inter-scan reproducibilility of measurement of coronary calcium using images from MDCT is excellent, irrespective of slice thickness and type of calcium parameter

    Alumina-on-Polyethylene Bearing Surfaces in Total Hip Arthroplasty

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    The long-term durability of polyethylene lining total hip arthroplasty (THA) mainly depends on periprosthetic osteolysis due to wear particles, especially in young active patients. In hip simulator study, reports revealed significant wear reduction of the alumina ceramic-on-polyethylene articulation of THA compared with metal-on-polyethylene bearing surfaces. However, medium to long-term clinical studies of THA using the alumina ceramic-on-polyethylene are few and the reported wear rate of this articulation is variable. We reviewed the advantages and disadvantages of ceramicon- polyethylene articulation in THA, hip simulator study and retrieval study for polyethylene wear, in vivo clinical results of THA using alumina ceramic-on-polyethylene bearing surfaces in the literature, and new trial alumina ceramic-onhighly cross linked polyethylene bearing surfaces

    Etiologic Classification Criteria of ARCO on Femoral Head Osteonecrosis Part 1: Glucocorticoid-Associated Osteonecrosis.

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    BACKGROUND: Glucocorticoid usage, a leading cause of osteonecrosis of the femoral head (ONFH), and its prevalence was reported in 25%-50% of non-traumatic ONFH patients. Nevertheless, there have been no unified criteria to classify glucocorticoid-associated ONFH (GA-ONFH). In 2015, the Association Research Circulation Osseous addressed the issue of developing a classification scheme. METHODS: In June 2017, a task force was set up to conduct a Delphi survey concerning ONFH. The task force invited 28 experts in osteonecrosis/bone circulation from 8 countries. Each round of the Delphi survey consists of questionnaires, analysis of replies, and feedback reports to the panel. After 3 rounds of the survey, the panel reached a consensus on the classification criteria. The response rates were 100% (Round 1), 96% (Round 2), and 100% (Round 3), respectively. RESULTS: The consensus on the classification criteria of GA-ONFH included the following: (1) patients should have a history of glucocorticoid use >2 g of prednisolone or its equivalent within a 3-month period; (2) osteonecrosis should be diagnosed within 2 years after glucocorticoid usage, and (3) patients should not have other risk factor(s) besides glucocorticoids. CONCLUSION: Association Research Circulation Osseous established classification criteria to standardize clinical studies concerning GA-ONFH

    Bone Marrow Concentrate (BMC) Therapy in Musculoskeletal Disorders: Evidence-Based Policy Position Statement of American Society of Interventional Pain Physicians (ASIPP)

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    BACKGROUND: The use of bone marrow concentrate (BMC) for treatment of musculoskeletal disorders has become increasingly popular over the last several years, as technology has improved along with the need for better solutions for these pathologies. The use of cellular tissue raises a number of issues regarding the US Food and Drug Administration\u27s (FDA) regulation in classifying these treatments as a drug versus just autologous tissue transplantation. In the case of BMC in musculoskeletal and spine care, this determination will likely hinge on whether BMC is homologous to the musculoskeletal system and spine. OBJECTIVES: The aim of this review is to describe the current regulatory guidelines set in place by the FDA, specifically the terminology around minimal manipulation and homologous use within Regulation 21 CFR Part 1271, and specifically how this applies to the use of BMC in interventional musculoskeletal medicine. METHODS: The methodology utilized here is similar to the methodology utilized in preparation of multiple guidelines employing the experience of a panel of experts from various medical specialties and subspecialties from differing regions of the world. The collaborators who developed these position statements have submitted their appropriate disclosures of conflicts of interest. Trustworthy standards were employed in the creation of these position statements. The literature pertaining to BMC, its effectiveness, adverse consequences, FDA regulations, criteria for meeting the standards of minimal manipulation, and homologous use were comprehensively reviewed using a best evidence synthesis of the available and relevant literature. RESULTS/Summary of Evidence: In conjunction with evidence-based medicine principles, the following position statements were developed: Statement 1: Based on a review of the literature in discussing the preparation of BMC using accepted methodologies, there is strong evidence of minimal manipulation in its preparation, and moderate evidence for homologous utility for various musculoskeletal and spinal conditions qualifies for the same surgical exemption. Statement 2: Assessment of clinical effectiveness based on extensive literature shows emerging evidence for multiple musculoskeletal and spinal conditions. • The evidence is highest for knee osteoarthritis with level II evidence based on relevant systematic reviews, randomized controlled trials and nonrandomized studies. There is level III evidence for knee cartilage conditions. • Based on the relevant systematic reviews, randomized trials, and nonrandomized studies, the evidence for disc injections is level III. • Based on the available literature without appropriate systematic reviews or randomized controlled trials, the evidence for all other conditions is level IV or limited for BMC injections. Statement 3: Based on an extensive review of the literature, there is strong evidence for the safety of BMC when performed by trained physicians with the appropriate precautions under image guidance utilizing a sterile technique. Statement 4: Musculoskeletal disorders and spinal disorders with related disability for economic and human toll, despite advancements with a wide array of treatment modalities. Statement 5: The 21st Century Cures Act was enacted in December 2016 with provisions to accelerate the development and translation of promising new therapies into clinical evaluation and use. Statement 6: Development of cell-based therapies is rapidly proliferating in a number of disease areas, including musculoskeletal disorders and spine. With mixed results, these therapies are greatly outpacing the evidence. The reckless publicity with unsubstantiated claims of beneficial outcomes having putative potential, and has led the FDA Federal Trade Commission (FTC) to issue multiple warnings. Thus the US FDA is considering the appropriateness of using various therapies, including BMC, for homologous use. Statement 7: Since the 1980\u27s and the description of mesenchymal stem cells by Caplan et al, (now called medicinal signaling cells), the use of BMC in musculoskeletal and spinal disorders has been increasing in the management of pain and promoting tissue healing. Statement 8: The Public Health Service Act (PHSA) of the FDA requires minimal manipulation under same surgical procedure exemption. Homologous use of BMC in musculoskeletal and spinal disorders is provided by preclinical and clinical evidence. Statement 9: If the FDA does not accept BMC as homologous, then it will require an Investigational New Drug (IND) classification with FDA (351) cellular drug approval for use. Statement 10: This literature review and these position statements establish compliance with the FDA\u27s intent and corroborates its present description of BMC as homologous with same surgical exemption, and exempt from IND, for use of BMC for treatment of musculoskeletal tissues, such as cartilage, bones, ligaments, muscles, tendons, and spinal discs. CONCLUSIONS: Based on the review of all available and pertinent literature, multiple position statements have been developed showing that BMC in musculoskeletal disorders meets the criteria of minimal manipulation and homologous use. KEY WORDS: Cell-based therapies, bone marrow concentrate, mesenchymal stem cells, medicinal signaling cells, Food and Drug Administration, human cells, tissues, and cellular tissue-based products, Public Health Service Act (PHSA), minimal manipulation, homologous use, same surgical procedure exemption
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