Osteopenia: a diagnostic and therapeutic challenge

Biomechanical comparison of all-polyethylene total knee replacement and its metal-backed equivalent on periprosthetic tibia using the finite element method

BACKGROUND

Total knee arthroplasty (TKA) with all-polyethylene tibial (APT) components has shown comparable survivorship and clinical outcomes to that with metal-backed tibial (MBT). Although MBT is more frequently implanted, APT equivalents are considered a low-cost variant for elderly patients. A biomechanical analysis was assumed to be suitable to compare the response of the periprosthetic tibia after implantation of TKA NexGen APT and MBT equivalent.

METHODS

A standardised load model was used representing the highest load achieved during level walking. The geometry and material models were created using computed tomography data. In the analysis, a material model was created that represents a patient with osteopenia.

RESULTS

The equivalent strain distribution in the models of cancellous bone with an APT component showed values above 1000 με in the area below the medial tibial section, with MBT component were primarily localised in the stem tip area. For APT variants, the microstrain values in more than 80% of the volume were in the range from 300 to 1500 με, MBT only in less than 64% of the volume.

CONCLUSION

The effect of APT implantation on the periprosthetic tibia was shown as equal or even superior to that of MBT despite maximum strain values occurring in different locations. On the basis of the strain distribution, the state of the bone tissue was analysed to determine whether bone tissue remodelling or remodelling would occur. Following clinical validation, outcomes could eventually modify the implant selection criteria and lead to more frequent implantation of APT components.

Quality of life in postmenopausal women with osteoporosis and osteopenia: associations with bone microarchitecture and nutritional status

PURPOSE

Primary aim of the study was to investigate the status of different health-related quality of life (HRQoL) domains in postmenopausal women with osteoporosis and osteopenia, and to explore possible associations with bone microarchitecture and nutritional status.

METHODS

This was a single-center cross-sectional study that included 232 postmenopausal women, from which they were divided into three groups-osteoporosis (OP, N = 63), osteopenia (OPIA, N = 123), and control group (N = 46). Detailed medical history data and anthropometric measurements were taken from all women. Bone structure parameters were taken with DXA device, with additional analysis of bone microarchitecture status with Trabecular Bone Score (TBS). Nutritional status was assessed with Mini Nutritional Assessment (MNA) questionnaire, and HRQoL with Medical Outcomes Study Short Form-36 (SF-36) questionnaire.

RESULTS

Nutrition evaluation analysis have shown that patients in OP group had significantly lower values of MNA score compared to the OPIA group and control group (P = 0.005). Furthermore, a significant positive correlation was found between all of the SF-36 domains and MNA scores, while significant positive correlation was found between TBS values and Physical functioning (P < 0.001), Bodily pain (P = 0.027), Social functioning (P = 0.029), and Vitality domains (P = 0.041) in total investigated population. Further analyses were performed only in OP and OPIA groups, and TBS score showed significant positive correlation with Physical functioning (r = 0.248, P < 0.001) and Bodily pain domains as well (r = 0.180, P = 0.014), while MNA score positively correlated with each of the SF-36 domains. Multiple regression models have shown that MNA score retained significant association with each SF-36 domains, and TBS value with Physical functioning (P = 0.003), Social functioning (P = 0.012), and Vitality domains (P = 0.014).

CONCLUSION

This study highlights the associations that TBS has with some domains of HRQoL in postmenopausal women with osteoporosis and osteopenia. Moreover, nutritional status could play a role in the complex interplay between TBS and HRQoL.

Changes in Bone Mineral Density and Serum Lipids across the First Postpartum Year: Effect of Aerobic Fitness and Physical Activity

This study evaluated the changes in bone mineral density (BMD) and serum lipids across the first postpartum year in lactating women compared to never-pregnant controls, and the influence of physical activity (PA). The study also explored whether N-telopeptides, pyridinoline, and deoxypyridinoline in urine serve as biomarkers of bone resorption. A cohort of 18 initially lactating postpartum women and 16 never pregnant controls were studied. BMD (dual energy X-ray absorptiometry), serum lipid profiles, and PA (Baecke PA Questionnaire) were assessed at baseline (4–6 weeks postpartum), 6 months, and 12 months. Postpartum women lost 5.2 ± 1.4 kg body weight and BMD decreased by 1.4% and 3.1% in the total body and dual-femur, respectively. Furthermore, BMDdid not show signs of rebound. Lipid profiles improved, with increases in high-density lipoprotein-cholesterol (HDL-C) and decreases in low-density lipoprotein cholesterol (LDL-C) and the cholesterol/HDL-C ratio at 12 months (vs. baseline). These changes were not influenced by lactation, but the fall the Cholesterol/HDL-C ratio was influenced by leisure-time (p = 0.051, time X group) and sport (p = 0.028, time effect) PA. The decrease in BMD from baseline to 12 months in total body and dual femur, however, was greater in those who continued to breastfeed for a full year compared to those who stopped at close to 6 months. Urinary markers of bone resorption, measured in a subset of participants, reflect BMD loss, particularly in the dual-femur, and may reflect changes bone resorption before observed changes in BMD. Results provide support that habitual postpartum PA may favorably influence changes in serum lipids but not necessarily BMD. The benefit of exercise and use of urinary biomarkers of bone deserves further exploration.

Extract and fraction of Musa paradisiaca flower have osteogenic effect and prevent ovariectomy induced osteopenia

BACKGROUND

Osteoporosis is an asymptomatic bone disorder leading to altered bone microarchitecture, mineralization and strength. Musa paradisiaca has been reported to have antioxidant and anti-inflammatory effects in various diseases. Its impact on postmenopausal osteoporosis has not been investigated yet.

PURPOSE

The intention of the current study was to evaluate the bone regeneration and osteoprotective potential of extract and fraction of M. paradisiaca flower in ovariectomized (Ovx) Sprague Dawley (SD) rats, a model of post-menopausal bone loss. The study also aims to identify osteogenic compounds from active fraction.

METHODS

Ethanolic extract (MFE) and butanolic fraction (MFE-Bu) from flower of M. paradisiaca were prepared and their efficacy was tested in rat femur osteotomy model at different doses. Effective dose from both extract (250 mg/kg) and fraction (50 mg/kg) were taken for study in osteopenic bone loss model. PTH was taken as reference standard (20 µg/kg/twice a week). Bones were harvested at autopsy for dynamic and static histomorphometry. Serum was collected for ELISA. Pure compounds were isolated from butanolic fraction (MFE-Bu), and were assessed for their osteogenic effect.

RESULTS

MFE and MFE-Bu were observed for their potential in bone healing and prevention of bone loss. Both MFE and MFE-Bu promoted new bone regeneration at injury site as assessed by microCT and calcein dye labeling studies. These also led to restoration of bone microarchitecture deteriorated as a result of osteopenia and improved bone biomechanical properties. Extract as well as the fraction exhibited dual bone anabolic and anti-resorptive properties where they elevated serum procollagen type I N-terminal propeptide (P1NP), a bone formation marker and suppressed serum C-telopeptide of type I collagen (CTX-1), a bone resorption marker. As many as four osteogenic compounds were isolated from MFE-Bu. Oleracein-E was found to be the most potent osteogenic agent based on osteoblast differentiation, mineralization assays, qPCR and protein expression studies.

CONCLUSION

Our studies demonstrates that ethanolic extract from the flower of M. paradisiaca and its butanolic fraction exhibit dual osteogenic and anti-resorptive potential, and have an advantage over PTH which though promotes bone formation but is also bone catabolic in nature.

Oligopin® Supplementation Mitigates Oxidative Stress in Postmenopausal Women with Osteopenia: A Randomized, Double-blind, Placebo-Controlled Trial

BACKGROUND

Evidence indicates a close association between oxidative stress and the etiopathogenesis of osteopenia. In vitro and animal studies report that Oligopin®, an extract of French maritime pine bark extract, has beneficial effects on oxidative stress.

PURPOSE

Here, we aimed to determine whether supplementation with Oligopin® affects bone turnover markers, antioxidant enzymes, and oxidative stress markers in these patients.

METHODS

Forty-three postmenopausal women with osteopenia were randomized in a placebo-controlled, double-blind clinical trial to receive either 150 mg/day Oligopin® (n = 22) or placebo (n = 21) for 12 weeks. Plasma levels of bone turnover markers; osteocalcin (OC), type I collagen cross-linked C-telopeptide (CTX-1), OC/CTX1 ratio along with total antioxidant capacity(TAC), malondialdehyde (MDA) concentration, protein carbonyl, and total thiol contents in plasma, activities of manganese superoxide dismutase (MnSOD) and catalase in both peripheral blood mononuclear cells (PBMCs) and plasma as well as mRNA expression of MnSOD, catalase, and Nrf2 in PBMCs were measured at the baseline and the end of the intervention.

RESULTS

Oligopin® supplementation significantly increased OC levels and the ratio of OC to CTX1 in women with osteopenia compared to placebo intervention after 12 weeks. Oligopin® significantly decreased plasma protein carbonyl content in postmenopausal women compared with the after placebo treatment. Moreover, Oligopin® intervention significantly increased plasma total thiol content, TAC, plasma activity of both MnSOD and catalase, and the transcript level of Nrf2, MnSOD, and catalase in comparison with the placebo group.

CONCLUSION

Supplementation with 150 mg/day Oligopin® for 12 weeks exerts beneficial effects in postmenopausal osteopenia through improving the antioxidant defense system in the plasma and PBMCs that was accompanied by an increase in indicators of bone turnover.

Osteoporosis in patients with rheumatoid arthritis: an update in epidemiology, pathogenesis, and fracture prevention

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic disabling disease characterized by a symmetrical articular involvement due to ongoing joint inflammation, if left insufficiently treated. Local and generalized bone loss is one of the main extra-articular complications of RA and leads to an increased risk for fragility fractures, which further impair functional ability, quality of life, and life expectancy. Therefore, there is an urgent need for good fracture risk management in the vulnerable RA patient.

AREAS COVERED

The authors review: the epidemiology and pathophysiology (i.e. risk factors) of osteoporosis (OP), fracture, and vertebral fracture risk assessment, the effects of anti-rheumatic drugs on bone loss, pharmacological treatment of OP in RA including both bisphosphonates (BP) and newer drugs including anti-resorptives and osteoanabolic treatment options.

EXPERT OPINION

Patients with active RA have elevated bone resorption and local bone loss. Moreover, these patients are at increased risk for generalized bone loss, vertebral and non-vertebral fractures. Since general risk factors (such as low BMI, fall risk) and RA-related factors play a role, optimal fracture prevention in RA patients is based on optimal diagnostics based on both of these factors, and on the use of adequate non-medical and medical treatment options.

Fall Prevention and Anti-Osteoporosis in Osteopenia Patients of 80 Years of Age and Older: A Randomized Controlled Study

To evaluate the effects of two fall‐prevention and anti‐osteoporotic protocols in elderly patients with osteopenia (OPA).

Methods

The present randomized controlled study included patients with OPA (n =123). The age of these patients was ≥80 years old, with the mean age of 83.54 ± 2.99 years, and the male‐to‐female ratio was 2.97:1.00. Fall‐prevention guidance was given to all patients. Patients in the experiment group (n = 62) orally received 600 mg/d of calcium carbonate, 0.5 μg/d of alfacalcidol, and 70 mg/week of alendronate, while patients in the control group (n = 61) orally received 600 mg/d of calcium carbonate and 0.5 μg/d of alfacalcidol for 18 months. The grip strength, gait speed, bone turnover markers, serum calcium, serum phosphorus, parathyroid hormone (PTH), and bone mineral density were measured, and the Timed Up and Go (TUG) test and the chair rising test (CRT) were performed. Falls, fragility fractures, medication compliance, and side effects of the drugs were recorded.

Results

The serum levels of bone turnover markers (type I procollagen amino‐terminal peptide [P1NP], type I collagen carboxyl terminal peptide [β‐CTx], and osteocalcin [OC]) decreased, while the bone mineral density of the lumbar spine and bilateral femoral neck increased after treatment in the experiment group (P < 0.05, P < 0.01). The rate of change in bone mineral density of the bilateral femoral neck was higher in the experiment group than the control group (3.43% vs 0.03%, P < 0.05; 2.86% vs −0.02%, P < 0.01). After treatment, the proportion of patients with increased hip T scores in the experiment group (66.1%, 41/62) was significantly higher than the proportion (35.0%, 21/60) in the control group (P = 0.001). The incidence of fall decreased in both groups after treatment compared to that before treatment (54.8% vs 33.9% and 54.1% vs 36.7%, respectively; P < 0.05). The incidence of fragility fractures was lower in the experiment group than the control group (8.1% vs 20.0%, P = 0.057). During the intervention period, the incidence of fragility fractures in patients who did not fall (3.8%, 3/79) was significantly lower than that in patients who fell (32.6%, 14/43) (P = 0.000). The risk of fragility fractures was significantly lower in patients who did not fall compared to patients who fell (relative risk: 0.117, 95% confidence interval: 0.035–0.384).

Conclusion

The combination of alendronate sodium with alfacalcidol and calcium can significantly improve the bone mineral density of the lumbar spine and femoral neck. For older patients with OPA, subjectively paying attention to avoiding falls can significantly reduce the risk of fragility fractures.

Pharmacological Management of Osteoporosis in Rheumatoid Arthritis Patients: A Review of the Literature and Practical Guide

Rheumatoid arthritis (RA) is a chronic disabling disease that is associated with increased localized and generalized osteoporosis (OP). Previous studies estimated that approximately one-third of the RA population experience bone loss. Moreover, RA patients suffer from a doubled fracture incidence depending on several clinical factors, such as disease severity, age, glucocorticoid (GC) use, and immobility. As OP fractures are related to impaired quality of life and increased mortality rates, OP has an enormous impact on global health status. Therefore, there is an urgent need for a holistic approach in daily clinical practice. In other words, both OP- and RA-related factors should be taken into account in treatment guidelines for OP in RA. First, to determine the actual fracture risk, dual-energy X-ray absorptiometry (DXA), including vertebral fracture assessment (VFA) and calculation of the 10-year fracture risk with FRAX^®, should be performed. In case of high fracture risk, calcium and vitamin D should be supplemented alongside anti-osteoporotic treatment. Importantly, RA treatment should be optimal, aiming at low disease activity or remission. Moreover, GC treatment should be at the lowest possible dose. In this way, good fracture risk management will lead to fracture risk reduction in RA patients. This review provides a practical guide for clinicians regarding pharmacological treatment options in RA patients with OP, taking into account both osteoporotic-related factors and factors related to RA.

Management of osteoporosis in rheumatoid arthritis patients

INTRODUCTION

In rheumatoid arthritis (RA) patients, the risk of both vertebral and non-vertebral fractures is roughly doubled, which is for an important part caused by inflammation-mediated amplification of bone loss and by immobilization. New treatments have become available in the last two decades to treat both RA and osteoporosis.

AREAS COVERED

Epidemiology and assessment of osteoporosis and fracture risk (including the influence of RA disease activity and bone-influencing medications such as glucocorticoids), the importance of vertebral fracture assessment in addition to bone density measurement in patients with RA, the use of disease-modifying antirheumatic drugs and their effects on generalized bone loss, and current and possible future anti-osteoporotic pharmacotherapeutic options are discussed with special focus on RA.

EXPERT OPINION

Assessment of osteoporosis in RA patients should include evaluation of the effects of disease activity and bone-influencing medications such as (the dose of) glucocorticoids, above standard risk factors for fractures or osteoporosis as defined by the FRAX instrument. Disease-modifying antirheumatic drugs are now well able to control disease activity using treat to target strategies. This lowering of disease activity by antirheumatic medications such as anti-TNF-α results in hampering of generalized bone loss; however, no fracture data are currently available. When treating osteoporosis in RA patients, additional focus should be on calcium supplementation, particularly in glucocorticoid users, and also on sufficient vitamin D use. Several anti-osteoporotic medications are now on the market; oral bisphosphonates are most commonly used, but in recent years, more agents have entered the market such as the parenteral antiresorptives denosumab (twice yearly) and zoledronic acid (once yearly), and the anabolic agent parathyroid hormone analogues. New agents, such as odanacatib and monoclonal antibodies against sclerostin, are now being tested and will most likely enlarge the possibilities of osteoporosis treatment in RA patients.

Can bone loss in rheumatoid arthritis be prevented?

Rheumatoid arthritis (RA) is a systemic inflammatory disease that can lead to local joint deformations (bone erosions and joint space narrowing) and to extra-articular phenomena, including generalized osteoporosis. In addition, in patients with RA, the risk of vertebral and nonvertebral fractures is doubled. High disease activity (inflammation), immobility, and glucocorticoid use are common factors that substantially increase fracture risk in these patients, on top of the background fracture risk based on classical risk factors such as high age, low body mass, and female gender. New insights on the links between the immune system and the bone system, the field of osteoimmunology, have shown that local and generalized bone loss share common pathways. The receptor activator of nuclear factor κB ligand/osteoprotegerin pathway (RANKl/OPG) is one of the most important pathways, as it is (strongly) upregulated by inflammation. In modern treatment of RA with biologics, for example, TNFα-blocking agents and combination therapy of conventional disease-modifying antirheumatic drugs (DMARDs), clinical remission is a realistic treatment goal. As a consequence, in recent studies, it has been documented that both local and generalized bone loss is absent or minimal in those patients who are in clinical remission.

Osteoporosis - a current view of pharmacological prevention and treatment

Postmenopausal osteoporosis is the most common bone disease, associated with low bone mineral density (BMD) and pathological fractures which lead to significant morbidity. It is defined clinically by a BMD of 2.5 standard deviations or more below the young female adult mean (T-score =−2.5). Osteoporosis was a huge global problem both socially and economically – in the UK alone, in 2011 £6 million per day was spent on treatment and social care of the 230,000 osteoporotic fracture patients – and therefore viable preventative and therapeutic approaches are key to managing this problem within the aging population of today. One of the main issues surrounding the potential of osteoporosis management is diagnosing patients at risk before they develop a fracture. We discuss the current and future possibilities for identifying susceptible patients, from fracture risk assessment to shape modeling and in relation to the high heritability of osteoporosis now that a plethora of genes have been associated with low BMD and osteoporotic fracture. This review highlights the current therapeutics in clinical use (including bisphosphonates, anti-RANKL [receptor activator of NF-κB ligand], intermittent low dose parathyroid hormone, and strontium ranelate) and some of those in development (anti-sclerostin antibodies and cathepsin K inhibitors). By highlighting the intimate relationship between the activities of bone forming (osteoblasts) and bone-resorbing (osteoclasts) cells, we include an overview and comparison of the molecular mechanisms exploited in each therapy.

Bone density, bone quality, and FRAX: changing concepts in osteoporosis management

Bone densitometry was originally developed to diagnose a high risk for fragility fractures in older postmenopausal women who may have primary osteoporosis. Its widespread availability, however, has led to its use in healthy peri- and premenopausal patients and the unexpected findings of low bone density in this group of patients. Their low bone density caused much uncertainty about the likelihood of fracture risk and what treatment might be needed. Conceptually, bone density reflected bone strength, and so a low density reflected increased fracture risk. Clinical experience and the results of pivotal studies of therapy for osteoporosis suggested that bone density was only partly responsible for skeletal strength. Many structural and material properties of bone, not measured by bone density, made it resist fracturing. Clinical risk factors helped determine these characteristics, albeit imperfectly, and aided clinicians decide whether and what treatment was needed. But now, new fracture risk assessment protocols (namely, FRAX, the WHO risk assessment tool) are available to help resolve this dilemma. This paper reviews some of the clinical observations that led to rethinking the concept bone density and bone strength and how it changes the clinical approach to therapy for the healthy young patient.

Trabecular architecture and vertebral fragility in osteoporosis

Osteoporosis heightens vertebral fragility owing to the biomechanical effects of diminished bone structure and composition. These biomechanical effects are only partially explained by loss in bone mass, so additional factors that are independent of bone mass are also thought to play an important role in vertebral fragility. Recent advances in imaging equipment, imaging-processing methods, and computational capacity allow researchers to quantify trabecular architecture in the vertebra at the level of the individual trabecular elements and to derive biomechanics-based measures of architecture that are independent of bone mass and density. These advances have shed light on the role of architecture in vertebral fragility. In addition to the adverse biomechanical consequences associated with trabecular thinning and loss of connectivity, a reduction in the number of vertical trabecular plates appears to be particularly harmful to vertebral strength. In the clinic, detailed architecture analysis is primarily applied to peripheral sites such as the distal radius and tibia. Analysis of trabecular architecture at these peripheral sites has shown mixed results for discriminating between patients with and without a vertebral fracture independent of bone mass, but has the potential to provide unique insight into the effects of therapeutic treatments. Overall, it does appear that trabecular architecture has an independent role on vertebral strength. Additional research is required to determine how and where architecture should be measured in vivo and whether assessment of trabecular architecture in a clinical setting improves prospective fracture risk assessment for the vertebra.