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Harry K Genant

Publications and source records attributed to Harry K Genant.

At least 19 recordsLinked to original sources

Effects of abatacept in patients with methotrexate-resistant active rheumatoid arthritis: a randomized trial.

BACKGROUND: The selective co-stimulation modulator abatacept demonstrated efficacy for treating rheumatoid arthritis in early clinical studies. OBJECTIVE: To evaluate the effects of abatacept in patients with persistent, active rheumatoid arthritis despite methotrexate treatment. DESIGN: One-year, multicenter, randomized, double-blind, placebo-controlled trial (November 2002 to October 2004). SETTING: 116 centers worldwide. PATIENTS: 652 patients with active rheumatoid arthritis despite methotrexate treatment. INTERVENTION: Once-monthly infusion of a fixed dose of abatacept, approximately 10 mg/kg of body weight, or placebo. MEASUREMENTS: Co-primary end points were a 20% improvement in American College of Rheumatology (ACR) response criteria (ACR 20) at 6 months, clinically meaningful improvements in physical function, and change from baseline in joint erosion score at 1 year. RESULTS: Four hundred thirty-three and 219 patients were randomly assigned to abatacept or placebo, respectively, and 385 (89%) and 162 (74%), respectively, completed 1 year of treatment. In a modified intention-to-treat analysis, 6-month ACR 20, ACR 50, and ACR 70 responses were 67.9% for abatacept versus 39.7% for placebo (difference, 28.2 percentage points [95% CI, 19.8 to 36.7 percentage points]), 39.9% for abatacept versus 16.8% for placebo (difference, 23.0 percentage points [CI, 15.0 to 31.1 percentage points]), and 19.8% for abatacept versus 6.5% for placebo (difference, 13.3 percentage points [CI, 7.0 to 19.5 percentage points]), respectively. At 1 year, the responses increased to 73.1% for abatacept versus 39.7% for placebo (difference, 33.4 percentage points [CI, 25.1 to 41.7 percentage points]), 48.3% for abatacept versus 18.2% for placebo (difference, 30.1 percentage points [CI, 21.8 to 38.5 percentage points]), and 28.8% for abatacept versus 6.1% for placebo (difference, 22.7 percentage points [CI, 15.6 to 29.8 percentage points]), respectively (P < 0.001 for all). Physical function significantly improved in 63.7% versus 39.3% of patients (P < 0.001). At 1 year, abatacept statistically significantly slowed the progression of structural joint damage compared with placebo. Abatacept-treated patients had a similar incidence of adverse events (87.3% vs. 84.0%; difference, 3.3 percentage points [CI, -2.5 to 9.1 percentage points]) and a higher incidence of prespecified serious infections (2.5% vs. 0.9%; difference, 1.6 percentage points [CI, -0.3 to 3.6 percentage points]) and infusion reactions (acute, 8.8% vs. 4.1%; difference, 4.7 percentage points [CI, 0.9 to 8.4 percentage points]; peri-infusional, 24.5% vs. 16.9%; difference, 7.6 percentage points [CI, 1.2 to 14.0 percentage points]) compared with placebo recipients. LIMITATIONS: The study involved only 1 group of patients over 1 year. CONCLUSIONS: Abatacept statistically significantly reduced disease activity in patients with rheumatoid arthritis and an inadequate response to methotrexate. Longer treatment in different patient populations is needed to establish its appropriate role in rheumatoid arthritis.

Abatacept↗

A selective p38 alpha mitogen-activated protein kinase inhibitor reverses cartilage and bone destruction in mice with collagen-induced arthritis.

Destruction of cartilage and bone is a poorly managed hallmark of human rheumatoid arthritis (RA). p38 Mitogen-activated protein kinase (MAPK) has been shown to regulate key proinflammatory pathways in RA, including tumor necrosis factor alpha, interleukin (IL)-1beta, and cyclooxygenase-2, as well as the process of osteoclast differentiation. Therefore, we evaluated whether a p38alpha MAPK inhibitor, indole-5-carboxamide (SD-282), could modulate cartilage and bone destruction in a mouse model of RA induced with bovine type II collagen [collagen-induced arthritis (CIA)]. In mice with early disease, SD-282 treatment significantly improved clinical severity scores, reduced bone and cartilage loss, and reduced mRNA levels of proinflammatory genes in paw tissue, including IL-1beta, IL-6, and cyclooxygenase-2. Notably, SD-282 treatment of mice with advanced disease resulted in significant improvement in clinical severity scoring and paw swelling, a reversal in bone and cartilage destruction as assessed by histology, bone volume fraction and thickness, and three-dimensional image analysis. These changes were accompanied by reduced osteoclast number and lowered levels of serum cartilage oligomeric matrix protein, a marker of cartilage breakdown. Thus, in a model of experimental arthritis associated with significant osteolysis, p38alpha MAPK inhibition not only attenuates disease progression but also reverses cartilage and bone destruction in mice with advanced CIA disease.

Animals↗

Advanced imaging assessment of bone quality.

Noninvasive and/or nondestructive techniques can provide structural information about bone, beyond simple bone densitometry. While the latter provides important information about osteoporotic fracture risk, many studies indicate that bone mineral density (BMD) only partly explains bone strength. Quantitative assessment of macrostructural characteristics, such as geometry, and microstructural features, such as relative trabecular volume, trabecular spacing, and connectivity, may improve our ability to estimate bone strength. Methods for quantitatively assessing macrostructure include (besides conventional radiographs) dual X ray absorptiometry (DXA) and computed tomography (CT), particularly volumetric quantitative computed tomography (vQCT). Methods for assessing microstructure of trabecular bone noninvasively and/or nondestructively include high-resolution computed tomography (hrCT), microcomputed tomography (micro-CT), high-resolution magnetic resonance (hrMR), and micromagnetic resonance (micro-MR). vQCT, hrCT, and hrMR are generally applicable in vivo; micro-CT and micro-MR are principally applicable in vitro. Despite progress, problems remain. The important balances between spatial resolution and sampling size, or between signal-to-noise and radiation dose or acquisition time, need further consideration, as do the complexity and expense of the methods versus their availability and accessibility. Clinically, the challenges for bone imaging include balancing the advantages of simple bone densitometry versus the more complex architectural features of bone, or the deeper research requirements versus the broader clinical needs. The biological differences between the peripheral appendicular skeleton and the central axial skeleton must be further addressed. Finally, the relative merits of these sophisticated imaging techniques must be weighed with respect to their applications as diagnostic procedures, requiring high accuracy or reliability, versus their monitoring applications, requiring high precision or reproducibility.

Bone and Bones↗

Incidence and risk factors for vertebral fracture in women and men: 25-year follow-up results from the population-based Framingham study.

UNLABELLED: This study evaluates baseline characteristics of 704 women and men in the Framingham Study with respect to long-term risk of incident vertebral fracture. Incidence was 24% in women and 10% in men. Few factors in middle-aged persons, except prevalent (moderate) fracture and alcohol consumption (in men), predicted long-term incidence of vertebral fracture. INTRODUCTION: We studied potential risk factors in women and men in middle adult years to help identify individuals at increased long-term risk of vertebral fracture in advanced age. MATERIALS AND METHODS: Participants included Framingham cohort members who underwent radiographic examinations at baseline in 1967-1969 (mean age, 53 years) and follow-up in 1992-1993. Semiquantitative methods were used to determine incident fracture, defined as any vertebral body graded normal at baseline and at least mildly deformed (20-25% reduction or more in any vertebral height) at follow-up. Information on potential risk factors was obtained from examinations conducted at or before baseline radiography. RESULTS: Prevalence of vertebral fracture was similar (14%) in women and men, although incidence was greater in women (24%) than men (10%). Alcohol consumption increased fracture risk in men. Multivariable-adjusted ORs increased from 1.78 in men who consumed 1-3 oz of alcohol per week in middle-age years to 4.61 in those with intakes of > or =4 oz/week (trend, P = 0.0099). Age, height, weight, grip strength, physical activity, metacarpal cortical area, and estrogen use (in women) had little or no influence on cumulative incidence of vertebral fracture. Results were similar when fracture was restricted to (at least) moderate severity; however, participants with moderate to severe fracture prevalent at baseline had five times the incidence of moderate to severe fracture during follow-up compared with those without moderately to severe prevalent fractures. CONCLUSIONS: Few factors in middle-aged persons, except prevalent fracture and alcohol consumption (in men), predict long-term incidence of vertebral fracture. The explanation underlying this finding is not readily apparent, however, risk factors for vertebral fracture may be more relevant to older individuals, with respect to short-term fracture risk, than to middle-aged adults in relation to long-term risk with aging.

Age Factors↗

Racial differences in the prevalence of vertebral fractures in older men: the Baltimore Men's Osteoporosis Study.

Older black men have higher adjusted bone mineral density (BMD) and a lower adjusted rate of decline in hip BMD than older white men. There are few published data on the prevalence of morphometric vertebral fractures in older white men and no published data for older black men. The study's objective was to estimate the prevalence of vertebral fractures in older men and explore differences in prevalence between older white and black men. Subjects included five hundred forty-two men (415 white and 127 black) aged 65 and above (mean age of 74.0+/-5.7 years) participating in the longitudinal component of the Baltimore Men's Osteoporosis Study. Radiographs of the thoracic and lumbar spine were obtained using standard protocols and read for the presence of vertebral deformities using binary semiquantitative techniques. Quantitative morphometry was performed and vertebral fractures were defined using the Melton-Eastell method. BMD was measured at the femoral neck, total hip and lumbar spine. Participants also completed self- and interviewer-administered questionnaires and underwent standardized clinical examinations. One or more vertebral fractures were present in 30 of 514 men with available radiographs: estimated prevalence 5.8% (95% confidence intervals [CI]: 4.0, 8.3%). Prevalence was significantly higher in white than black men, 7.3% vs 0.9% (Fishers' exact p =0.01): age-adjusted odds ratio=8.3 (95% CI: 1.1, 62.5). Among white men, there was no significant difference in age-adjusted femoral neck or total hip BMD or frequency or severity of back pain between men with and without vertebral fractures. In conclusion, older white men have a higher prevalence of vertebral fractures than older black men. This may be related to differences in BMD between these groups.

Black or African American↗

What proportion of incident radiographic vertebral deformities is clinically diagnosed and vice versa?

UNLABELLED: We prospectively examined, in a large cohort of older women, the proportion of incident radiographic vertebral deformities diagnosed as incident clinical vertebral fractures in the same women at the same vertebral level. The proportion of deformities clinically diagnosed ranged from <15% for milder deformities to nearly 30% for more severe deformities. INTRODUCTION: The relationship between radiographic and clinical vertebral fractures is incompletely understood. No previous study has prospectively compared the agreement between incident radiographic vertebral deformities and incident community-recognized, radiographically confirmed vertebral fractures in the same women at the same vertebral level(s). MATERIALS AND METHODS: This analysis of data from the Fracture Intervention Trial included all participants who completed both baseline and at least one scheduled follow-up lateral spinal radiograph (n = 6084). Incident vertebral deformities were defined at a given vertebral level as a reduction between baseline and closeout radiographs of > or = 20% and 4 mm in any vertebral height and subdivided into two severity categories. Incident clinical vertebral fractures were those reported to clinical centers by participants and confirmed by the study radiologist, who compared the community spinal radiograph with the participant's baseline study radiograph using semiquantitative methods. RESULTS: A total of 446 incident radiographic vertebral deformities were identified in 330 women, whereas 121 women experienced one or more confirmed incident clinical vertebral fracture. Of incident radiograpic vertebral deformities, 22.6% were also clinically diagnosed as incident vertebral fractures, with clinical diagnoses made for 28.4% of the deformities that exceeded 30% and 4 mm height loss (severe deformity) compared with 14.3% for deformities that involved > or = 20% and 4 mm but < 30% height loss (milder deformity). Of incident clinical vertebral fractures, 72.7% were morphometrically identified as incident deformities, most of them as severe deformities. More than 20% of incident clinical fractures were not identified as incident deformities by even the most liberal morphometric criterion used in this study. CONCLUSIONS: Approximately one-fourth of incident radiographic vertebral deformities were clinically diagnosed as new vertebral fractures, although the proportion clinically diagnosed was increased for more severe deformities. Whereas most incident clinical vertebral fractures were identified as severe morphometric deformities, approximately one-fourth did not meet even the most liberal study criterion for morphometric deformity. Further study of factors that may explain the discordance between incident vertebral deformities and incident clinical vertebral fractures is important.

Aged↗

Short tau inversion recovery and proton density-weighted fat suppressed sequences for the evaluation of osteoarthritis of the knee with a 1.0 T dedicated extremity MRI: development of a time-efficient sequence protocol.

Aim of this study was to develop a time-efficient sequence protocol for a 1.0 T dedicated MR system to be used for whole-organ scoring of osteoarthritis (OA). Thirty-four knees were examined using a protocol that included fat suppressed fast spin echo proton density weighted sequences (PDFS) in three planes plus a coronal STIR sequence. Two radiologists scored each knee by consensus for five OA features. In separate sessions, all knees were scored using three different combinations of sequences: (1) all four sequences (reference protocol, 16 min 31 s scanning time), (2) three PDFS sequences without STIR ("No STIR", 12 min 25 s scanning time) and (3) sagittal and axial PDFS sequences plus a coronal STIR sequence ("No PDFS", 11 min 49 s scanning time). Agreement of the readings using both subsets of sequences compared to the reference protocol was evaluated using weighted kappa statistics. kappa-coefficients showed good or excellent agreement for both sequence subsets in comparison to the reference protocol for all assessed features. kappa-coefficients for No PDFS/No STIR: bone marrow abnormalities (0.74/0.67), subarticular cysts (0.84/0.63), marginal osteophytes (0.77/0.71), menisci (0.75/0.79), tibial cartilage (0.71/0.78). Optimization of sequence protocols consisting of three sequences results in time savings and cost efficiency in imaging of knee OA without loss of information over a more time consuming protocol.

Female↗

Bone marrow lesions in the knee are associated with increased local bone density.

OBJECTIVE: Bone marrow lesions are associated with pain and compartment-specific progression of joint space narrowing in patients with knee osteoarthritis (OA). Bone marrow lesions occur in regions under increased loading, and excess loading produces increased bone mineral density (BMD). The ratio of BMD in the medial tibial plateau compared with that in the lateral tibial plateau (M:L BMD ratio) reflects loading in the knee. Therefore, we hypothesized that a higher M:L BMD ratio would be associated with medial bone marrow lesions, and that lower ratios would be associated with lateral bone marrow lesions. METHODS: Participants in the Framingham Osteoarthritis Study underwent magnetic resonance imaging (MRI), measurement of bone mineral density (BMD), and knee radiography between 2002 and 2004. MRI was used to define medial and lateral bone marrow lesions in the medial and lateral tibiofemoral compartments, respectively. We performed a logistic regression analysis with medial bone marrow lesions as the outcome, testing M:L BMD ratio groups as predictor variables. We adjusted for age, sex, body mass index, and systemic BMD, using generalized estimating equations to adjust for correlations between knees. An identical analysis evaluating lateral bone marrow lesions was performed. RESULTS: Medial bone marrow lesions were strongly associated with a high M:L BMD ratio. The odds ratios (ORs) for prevalent medial bone marrow lesions, for the lowest to the highest quartile of M:L BMD ratios, were 1.0 (referent), 1.3, 5.0, and infinity (P for trend < 0.0001). Lateral bone marrow lesions were strongly associated with low M:L BMD ratios (the ORs for prevalent lateral bone marrow lesions, for the highest to the lowest quartile, were 1.0 [referent], 3.0, 26.8, and 54.0 [P for trend < 0.0001]). CONCLUSION: Medial bone marrow lesions occur in knees with relatively higher local medial tibial bone density, and lateral bone marrow lesions occur in knees with relatively higher lateral tibial bone density, supporting the hypothesis that local BMD reflects loading within the knee. Our findings emphasize the importance of loading in the pathophysiology of OA.

Aged↗

Application of micro-CT assessment of 3-D bone microstructure in preclinical and clinical studies.

As the mechanical competence of trabecular bone is a function of its apparent density and 3-D distribution, assessment of 3-D trabecular structural characteristics may improve our ability to understand the pathophysiology of osteoporosis, to test the efficacy of pharmaceutical intervention, and to estimate bone biomechanical properties. We have studied ovariectomy-induced osteopenia in rats and its treatment with agents such as estrogen and sodium fluoride. We have demonstrated that 3-D micro-computed tomography (microCT) can directly quantify mouse trabecular and cortical bone structure with an isotropic resolution of 6 microm(3). MicroCT is also useful for studying osteoporosis in mice and phenotypes of mice with gene manipulation, such as SHIP-knockout mice, which are severely osteoporotic due to increased numbers of hyperresorptive osteoclasts, PTHrP heterozygous-null mice, and mice with Zmpste24 deficiency. MicroCT can quantify osteogenesis in mouse Ilizarov leg-lengthening procedures, osteoconduction in a rat cranial defect model, and structural changes in arthritic rabbits, rats, and mice. In clinical studies, we evaluated longitudinal changes in the iliac crests. Paired bone biopsies from the same premenopausal and postmenopausal women showed the changes in 3-D trabecular structure, such as decreased trabecular thickness, shifting of trabecular model from platelike structure to rodlike structure, and decreased degree of anisotropy were remarkable. Treatment with PTH in postmenopausal women with osteoporosis significantly improved trabecular morphology with a shift toward a more platelike structure, increased trabecular connectivity density, and increased cortical thickness. Paired bone biopsy specimens from the iliac crest in postmenopausal women with osteoporosis before and an average of 2 years after beginning of estrogen replacement therapy demonstrated that posttreatment biopsies showed a significant change in the ratio of plates to rods and statistically insignificant changes in other 3-D trabecular parameters. Thus, microCT can characterize 3-D structure of various animal models, and the longitudinal changes in 3-D bone microarchitectural integrity that deteriorates in the transmenopausal period, is preserved with HRT, and is improved with PTH treatment in postmenopausal women.

Animals↗

Prognostic utility of a semiquantitative spinal deformity index.

The semiquantitative spinal deformity index (SDI) is a summary measure of the vertebral fracture status of the spine incorporating both the number and severity of vertebral fractures. For each vertebra, a visual semiquantitative grade of 0, 1, 2, or 3 is assigned for no fracture or mild, moderate, or severe fracture, respectively, and the SDI is calculated by summing the fracture grades of all vertebrae (T4 to L4). We investigated the effect of prevalent vertebral fracture number and severity, as integrated by the SDI, on 3-year vertebral fracture risk by performing logistic regression modeling with data from the MORE trial. There was a striking linear relationship between baseline SDI and the model-based vertebral fracture risk estimates, with a near-perfect correlation (r = 0.98, P < 0.001). However, the SDI may be overly simplistic, as a given SDI value can be attained through differing vertebral fracture scenarios (i.e., an SDI of 3 can be realized three ways), each corresponding to potentially different vertebral fracture risk. To address this issue, a second, more complex model was constructed that included individual predictor variables for number of mild, number of moderate, and number of severe prevalent vertebral fractures. The model-based risk estimates for vertebral fracture using the SDI and the more complex model were highly correlated (r = 0.91, P < 0.001), giving almost identical values up to an SDI of 5. Thus, for most clinical scenarios, it is not necessary to consider the particular fracture configuration that led to a given SDI score for predicting a patient's future vertebral fracture risk. These results validate the SDI as an accurate tool for assessing future vertebral fracture risk; patients with greater baseline SDI had greater future risk for vertebral fractures.

Aged↗

Reduction in vertebral fracture risk in teriparatide-treated postmenopausal women as assessed by spinal deformity index.

Teriparatide is the first bone-building drug available for the treatment of osteoporosis. We investigated the efficacy of this compound as assessed by spinal deformity index (SDI) using data from the Fracture Prevention Trial (FPT). The FPT was a randomized, double blind trial of placebo versus teriparatide 20 microg (TPTD20) versus teriparatide 40 microg (TPTD40) administered by daily self-injection. Patients included in the current analyses were those patients from the placebo (n = 398) and TPTD20 (the approved dose, n = 403) groups with baseline and follow-up radiographs and at least one vertebral fracture at baseline. For each vertebra, a visual semiquantitative grade of 0, 1, 2, or 3 was assigned for no fracture or mild, moderate, or severe fracture, respectively; the SDI was calculated by summing the fracture grades of all T4 to L4 vertebrae. The mean SDI increased in the placebo and TPTD20 groups by 0.485 and 0.134, respectively (P < 0.001). The proportions of patients with SDI increases >1, >2, and >3 were reduced by 85%, 80%, and 80%, respectively. In the placebo group, increasing baseline SDI was correlated with the mean increase in SDI during the trial (r = 0.080, P = 0.01), consistent with the progressive natural history of osteoporosis. However, in the TPTD20 group, increasing baseline SDI was not correlated with the mean increase in SDI during the trial (P = 0.297) indicating that teriparatide mitigated or eliminated the increased risk associated with increasing fracture burden. Increases in SDI during the trial were associated with increasing proportions of patients with new or worsening back pain and greater mean height loss (P < 0.0001), demonstrating an association with important clinical consequences. The results indicate that teriparatide greatly reduced the increase in fracture burden in the FPT and mitigated or eliminated the risk for future fractures imparted by increasing baseline fracture burden.

Aged↗

MR imaging of post-traumatic articular cartilage injuries confined to the femoral trochlea. Arthroscopic correlation and clinical significance.

OBJECTIVE: To assess and describe post-traumatic articular cartilage injuries isolated to the trochlear groove and provide insight into potential mechanism of injury. MATERIALS AND METHODS: We retrospectively evaluated MR imaging findings of all knee MRIs performed at our institution over the last 2 years (2450). Thirty patients met the criteria of a cartilage injury confined to the trochlear groove. In 15 cases, which were included in our study, arthroscopic correlation was available. Each plane was evaluated and graded for the presence and appearance of articular cartilage defects using a standard arthroscopic grading scheme adapted to MR imaging. Any additional pathological derangement was documented and information about the mechanism of injury was retrieved by chart review. RESULTS: In all cases the cartilaginous injury was well demonstrated on MRI. In 13 patients additional pathological findings could be observed. The most frequently associated injury was a meniscal tear in nine patients. In eight cases, the arthroscopic grading of the trochlear injury matched exactly with the MRI findings. In the remaining seven cases, the discrepancy between MRI and arthroscopy was never higher than one grade. In 13 out of 15 of patients trauma mechanism could be evaluated. Twelve patients suffered an indirect twisting injury and one suffered a direct trauma to their knee. CONCLUSION: The findings of this study demonstrate that MR imaging allows reliable grading of isolated injury to the trochlear groove cartilage and assists in directing surgical diagnosis and treatment. These injuries may be the only hyaline cartilage injury in the knee and meniscal tears are a frequently associated finding. Therefore, it is important to search specifically for cartilage injuries of the trochlear groove in patients with anterior knee pain, even if other coexistent pathology could potentially explain the patient's symptoms.

Adolescent↗

Osteoblast-derived PTHrP is a potent endogenous bone anabolic agent that modifies the therapeutic efficacy of administered PTH 1-34.

Mice heterozygous for targeted disruption of Pthrp exhibit, by 3 months of age, diminished bone volume and skeletal microarchitectural changes indicative of advanced osteoporosis. Impaired bone formation arising from decreased BM precursor cell recruitment and increased apoptotic death of osteoblastic cells was identified as the underlying mechanism for low bone mass. The osteoporotic phenotype was recapitulated in mice with osteoblast-specific targeted disruption of Pthrp, generated using Cre-LoxP technology, and defective bone formation was reaffirmed as the underlying etiology. Daily administration of the 1-34 amino-terminal fragment of parathyroid hormone (PTH 1-34) to Pthrp+/- mice resulted in profound improvement in all parameters of skeletal microarchitecture, surpassing the improvement observed in treated WT littermates. These findings establish a pivotal role for osteoblast-derived PTH-related protein (PTHrP) as a potent endogenous bone anabolic factor that potentiates bone formation by altering osteoblast recruitment and survival and whose level of expression in the bone microenvironment influences the therapeutic efficacy of exogenous PTH 1-34.

Animals↗

The effects of teriparatide on the incidence of back pain in postmenopausal women with osteoporosis.

OBJECTIVES: Back pain is a major cause of suffering, disability, and cost. The risk of developing back pain was assessed following treatment with teriparatide [rh(PTH 1-34)] in postmenopausal women with osteoporosis. RESEARCH DESIGN AND METHODS: A secondary analysis of back pain findings from the global, multi-site Fracture Prevention Trial was conducted where postmenopausal women with prevalent vertebral fractures were administered teriparatide 20 microg (n = 541) or placebo (n = 544) for a median of 19 months. Treatment-emergent back pain data were collected during adverse event monitoring, and spine radiographs were obtained at baseline and study endpoint. MAIN OUTCOME MEASURES: The risk of back pain stratified by severity of new or worsening back pain and the risk of back pain associated with both number and severity of new vertebral fractures. RESULTS: Women randomized to teriparatide 20 microg had a 31% reduced relative risk of moderate or severe back pain (16.5% vs. 11.5%, P = 0.016) and a 57% reduced risk of severe back pain (5.2% vs. 2.2%, P = 0.011). Compared with placebo, teriparatide-treated patients experienced reduced relative risk of developing back pain associated with findings of: one or more new vertebral fractures by 83% (6.5% vs. 1.1%, P < 0.001), two or more new vertebral fractures by 91% (2.5% vs. 0.20%, P = 0.004), and one or more new moderate or severe vertebral fractures by 100% (5.1% vs. 0.0%, P < 0.001). CONCLUSIONS: Teriparatide-treated women had reduced risk for moderate or severe back pain, severe back pain, and back pain associated with vertebral fractures. The mechanism of the back pain reduction likely includes the reduction both in severity and number of new vertebral fractures.

Back Pain↗

Micro-CT arthrography: a pilot study for the ex vivo visualization of the rat knee joint.

OBJECTIVE: In our study, we evaluated the potential of micro-CT for the assessment of the rat knee joint using ex vivo micro-CT arthrography. The aims of the study were to introduce the technique of micro-CT arthrography and to visualize the normal anatomy of the rat knee. The secondary aims were the quantification of retropatellar cartilage thickness and the analysis of microstructural cancellous bone parameters within the tibial epiphysis. CONCLUSION: Micro-CT arthrography is a novel technique for the indirect visualization of the distinct features and structural analysis of the rat knee joint. This technique represents an additional imaging and analysis tool in small-animal research.

Animals↗