Cyclic Tensile Strain Enhances Osteogenesis and Angiogenesis in Mesenchymal Stem Cells from Osteoporotic Donors

We have shown that the uniaxial cyclic tensile strain of magnitude 10% promotes and enhances osteogenesis of human mesenchymal stem cells (hMSC) and human adipose-derived stem cells (hASC) from normal, nonosteoporotic donors. In the present study, MSC from osteoporotic donors were analyzed for changes in mRNA expression in response to 10% uniaxial tensile strain to identify potential mechanisms underlying the use of this mechanical loading paradigm for prevention and treatment of osteoporosis. Human MSC isolated from three female, postmenopausal osteoporotic donors were analyzed for their responses to mechanical loading using microarray analysis of over 47,000 gene probes. Human MSC were seeded in three-dimensional collagen type I constructs to mimic the organic extracellular matrix of bone and 10% uniaxial cyclic tensile strain was applied to promote osteogenesis. Seventy-nine genes were shown to be regulated within hMSC from osteoporotic donors in response to 10% cyclic tensile strain. Upregulation of six genes were further confirmed with real-time RT-PCR: jun D proto-oncogene (JUND) and plasminogen activator, urokinase receptor (PLAUR), two genes identified as potential key molecules from network analysis; phosphoinositide-3-kinase, catalytic, delta polypeptide (PIK3CD) and wingless-type MMTV integration site family, member 5B (WNT5B), two genes with known importance in bone biology; and, PDZ and LIM domain 4 (PDLIM4) and vascular endothelial growth factor A (VEGFA), two genes that we have previously shown are significantly regulated in hASC in response to this mechanical stimulus. Function analysis indicated that 10% cyclic tensile strain induced expression of genes associated with cell movement, cell proliferation, and tissue development, including development in musculoskeletal and cardiovascular systems. Our results demonstrate that hMSC from aged, osteoporotic donors are capable of enhanced osteogenic differentiation in response to 10% cyclic tensile strain with significant increases in the expression of genes associated with enhanced cell proliferation, musculoskeletal development, and angiogenesis. Surprisingly, cyclic tensile strain of magnitude 10% not only enhanced osteogenesis in hMSC from osteoporotic donors, but also enhanced expression of angiogenic factors. Better understanding and methodologies to promote osteogenesis in hMSC from elderly, osteoporotic donors may greatly facilitate achieving long-term success in bone regeneration and functional bone tissue engineering for this ever-growing patient population

The effects of stochastic resonance electrical stimulation and neoprene sleeve on knee proprioception

<p>Abstract</p> <p>Background</p> <p>A variety of knee injuries and pathologies may cause a deficit in knee proprioception which may increase the risk of reinjury or the progression of disease. Stochastic resonance stimulation is a new therapy which has potential benefits for improving proprioceptive function. The objective of this study was to determine if stochastic resonance (SR) stimulation applied with a neoprene sleeve could improve knee proprioception relative to a no-stimulation/no-sleeve condition (control) or a sleeve alone condition in the normal, healthy knee. We hypothesized that SR stimulation when applied with a sleeve would enhance proprioception relative to the control and sleeve alone conditions.</p> <p>Methods</p> <p>Using a cross-over within subject design, twenty-four healthy subjects were tested under four combinations of conditions: electrical stimulation/sleeve, no stimulation/sleeve, no stimulation/no sleeve, and stimulation/no sleeve. Joint position sense (proprioception) was measured as the absolute mean difference between a target knee joint angle and the knee angle reproduced by the subject. Testing was conducted during both partial-weight bearing (PWB) and non-weight bearing (NWB) tasks. Differences in joint position sense between the conditions were evaluated by repeated-measures analysis of variance testing.</p> <p>Results</p> <p>Joint position sense error during the stimulation/sleeve condition (2.48° ± 1.32°) was found to be more accurate (P < 0.05) relative to the control condition (3.35° ± 1.63°) in the PWB task. No difference in joint position sense error was found between stimulation/sleeve and sleeve alone conditions for the PWB task. Joint position sense error was not found to differ between any of the conditions for the NWB task.</p> <p>Conclusion</p> <p>These results suggest that SR electrical stimulation when combined with a neoprene sleeve is an effective modality for enhancement of joint proprioception in the PWB knee. We believe these results suggest the need for further study of the potential of SR stimulation to correct proprioceptive deficits in a clinical population with knee injury/pathology or in subjects at risk of injury because of a proprioceptive deficit.</p

Fractures of the tibial plafond.

Tibial plafond fractures comprise a diverse group of articular, metaphyseal, and occasionally diaphyseal injuries and have in common injury to the articular surface of the distal tibia and significant associated soft-tissue injury. Injury to the soft tissues combined with the complex fracture patterns has led to high complication rates from surgical attempts to reduce and stabilize these fractures. Currently, there is a wide range of treatment techniques available for a wide spectrum of injury severity, surgeon experience, and surgeon preferences. Patient outcomes vary widely. Because these injuries are relatively uncommon, the amount of clinical data available to guide treatment decisions is limited. Careful classification and assessment of the fracture pattern and associated soft-tissue injury and an understanding of the principles of modern concepts of treatment should allow the surgeon to choose from among several treatment protocols, all of which emphasize minimizing complications to optimize patient outcomes

Declining rates of osteoporosis management following fragility fractures in the U.S., 2000 through 2009

Background: Clinical practice recommendations state that patients with fragility fractures should be evaluated for osteoporosis and treated for the disease if it is present. The purpose of this study was to assess osteoporosis evaluation and treatment patterns for patients with fragility fractures and assess whether anti-osteoporosis pharmacotherapy initiated immediately following a fragility fracture is associated with improved adherence to the treatment protocol. Methods: This retrospective cohort study involved data from a large commercially insured population seen in the period from 2001 through 2009. Patients were community-dwelling individuals aged fifty years or older who had a new low-energy fracture at the hip, vertebra, wrist, or humerus with no evidence of a fragility fracture, osteoporosis treatment, malignant disease, or Paget disease for twelve months preceding the fracture. Rates of diagnostic testing and pharmacotherapy for osteoporosis within twelve months post-fracture were evaluated. Patients treated with oral bisphosphonates were evaluated to determine whether twelve-month adherence to the treatment protocol differed between those who had initiated therapy sooner (at zero to ninety days) and those who initiated it later (at ninety-one to 365 days) following the fracture. Results: The 88,571 women and 41,984 men had an average age of 72.3 years and 70.5 years, respectively. Nineteen percent (16,464) of the women and 10% (4014) of the men initiated osteoporosis pharmacotherapy, and 30% (26,481) of the women and 15% (6427) of the men underwent diagnostic testing and/or pharmacotherapy following fracture. Treatment rates were highest following vertebral fracture and lowest following wrist or humeral fracture. Treatment rates significantly decreased over time (from 2001 through 2009). The average twelve-month adherence (medication possession ratio) was 56% and 61% among women and men, respectively. Adherence was similar between patients who had initiated treatment sooner after the fracture and those who had initiated it later after the fracture. Conclusions: Clinical guidelines for evaluation and treatment following fragility fracture were met for less than one-third of women and less than one-sixth of men. While primary fracture prevention remains the ideal, secondary prevention is critical and there is a need to reverse the downward trend in adherence to post-fracture guidelines. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2014 by the Journal of Bone and Joint Surgery, Incorporated

Declining rates of osteoporosis management following fragility fractures in the U.S., 2000 through 2009

Background: Clinical practice recommendations state that patients with fragility fractures should be evaluated for osteoporosis and treated for the disease if it is present. The purpose of this study was to assess osteoporosis evaluation and treatment patterns for patients with fragility fractures and assess whether anti-osteoporosis pharmacotherapy initiated immediately following a fragility fracture is associated with improved adherence to the treatment protocol. Methods: This retrospective cohort study involved data from a large commercially insured population seen in the period from 2001 through 2009. Patients were community-dwelling individuals aged fifty years or older who had a new low-energy fracture at the hip, vertebra, wrist, or humerus with no evidence of a fragility fracture, osteoporosis treatment, malignant disease, or Paget disease for twelve months preceding the fracture. Rates of diagnostic testing and pharmacotherapy for osteoporosis within twelve months post-fracture were evaluated. Patients treated with oral bisphosphonates were evaluated to determine whether twelve-month adherence to the treatment protocol differed between those who had initiated therapy sooner (at zero to ninety days) and those who initiated it later (at ninety-one to 365 days) following the fracture. Results: The 88,571 women and 41,984 men had an average age of 72.3 years and 70.5 years, respectively. Nineteen percent (16,464) of the women and 10% (4014) of the men initiated osteoporosis pharmacotherapy, and 30% (26,481) of the women and 15% (6427) of the men underwent diagnostic testing and/or pharmacotherapy following fracture. Treatment rates were highest following vertebral fracture and lowest following wrist or humeral fracture. Treatment rates significantly decreased over time (from 2001 through 2009). The average twelve-month adherence (medication possession ratio) was 56% and 61% among women and men, respectively. Adherence was similar between patients who had initiated treatment sooner after the fracture and those who had initiated it later after the fracture. Conclusions: Clinical guidelines for evaluation and treatment following fragility fracture were met for less than one-third of women and less than one-sixth of men. While primary fracture prevention remains the ideal, secondary prevention is critical and there is a need to reverse the downward trend in adherence to post-fracture guidelines. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2014 by the Journal of Bone and Joint Surgery, Incorporated

Cyclic Tensile Strain Enhances Osteogenesis and Angiogenesis in Mesenchymal Stem Cells from Osteoporotic Donors

We have shown that the uniaxial cyclic tensile strain of magnitude 10% promotes and enhances osteogenesis of human mesenchymal stem cells (hMSC) and human adipose-derived stem cells (hASC) from normal, nonosteoporotic donors. In the present study, MSC from osteoporotic donors were analyzed for changes in mRNA expression in response to 10% uniaxial tensile strain to identify potential mechanisms underlying the use of this mechanical loading paradigm for prevention and treatment of osteoporosis. Human MSC isolated from three female, postmenopausal osteoporotic donors were analyzed for their responses to mechanical loading using microarray analysis of over 47,000 gene probes. Human MSC were seeded in three-dimensional collagen type I constructs to mimic the organic extracellular matrix of bone and 10% uniaxial cyclic tensile strain was applied to promote osteogenesis. Seventy-nine genes were shown to be regulated within hMSC from osteoporotic donors in response to 10% cyclic tensile strain. Upregulation of six genes were further confirmed with real-time RT-PCR: jun D proto-oncogene (JUND) and plasminogen activator, urokinase receptor (PLAUR), two genes identified as potential key molecules from network analysis; phosphoinositide-3-kinase, catalytic, delta polypeptide (PIK3CD) and wingless-type MMTV integration site family, member 5B (WNT5B), two genes with known importance in bone biology; and, PDZ and LIM domain 4 (PDLIM4) and vascular endothelial growth factor A (VEGFA), two genes that we have previously shown are significantly regulated in hASC in response to this mechanical stimulus. Function analysis indicated that 10% cyclic tensile strain induced expression of genes associated with cell movement, cell proliferation, and tissue development, including development in musculoskeletal and cardiovascular systems. Our results demonstrate that hMSC from aged, osteoporotic donors are capable of enhanced osteogenic differentiation in response to 10% cyclic tensile strain with significant increases in the expression of genes associated with enhanced cell proliferation, musculoskeletal development, and angiogenesis. Surprisingly, cyclic tensile strain of magnitude 10% not only enhanced osteogenesis in hMSC from osteoporotic donors, but also enhanced expression of angiogenic factors. Better understanding and methodologies to promote osteogenesis in hMSC from elderly, osteoporotic donors may greatly facilitate achieving long-term success in bone regeneration and functional bone tissue engineering for this ever-growing patient population

Own the bone, a system-based intervention, improves osteoporosis care after fragility fractures

© 2016 By the Journal of Bone and Joint Surgery, Incorporated. Background: The goal of this study was to evaluate the effectiveness of the American Orthopaedic Association\u27s Own the Bone secondary fracture prevention program in the United States. Methods: The objective of this quality improvement cohort study was dissemination of Own the Bone and implementation of secondary prevention (osteoporosis pharmacologic and bone mineral density [BMD] test recommendations). The main outcome measures were the number of sites implementing Own the Bone and implementation of secondary prevention, i.e., orders for BMD testing and/or pharmacologic treatment. The 177 sites participating in the program were academic and community hospitals, orthopaedic surgery groups, and a health system; data were obtained from the first 125 sites utilizing its registry, between January 1, 2010, and March 31, 2015. It included all patients, aged 50 years or older, presenting with fragility fractures (n = 23,132) who were enrolled in the Own the Bone web-based registry. The interventions were education, development of program elements, dissemination, implementation, and evaluation of the Own the Bone program at participating sites. Results: A growing number of institutions implemented Own the Bone (14 sites in 2005-2006 to 177 sites in 2015). After consultation, 53% of patients had a BMD test ordered and/or pharmacologic therapy for osteoporosis