The relationship between osteoarthritis of the hands, bone mineral density, and osteoporotic fractures in elderly women

Spinal osteoarthritis is a risk of vertebral fractures in postmenopausal women

Recent studies have revealed that despite high bone mineral density (BMD), osteoarthritis (OA) is a risk factor for osteoporotic fractures. However, the relationship between spinal OA and vertebral fractures has not yet been fully investigated. This longitudinal analysis used a subset of ongoing cohort study consist with Japanese postmenopausal women. The prevalence of spinal OA was determined using Kellgren-Lawrence grading method. The incidence of vertebral fractures were determined by semiquantitative analysis of spinal X-ray films. The relationship between the presence of spinal OA and incidence of vertebral fractures was evaluated using the Cox regression analysis. In total, 1480 women were followed up for 8.1 ± 6.4 years. Among them, 923 were diagnosed with spinal OA, and incident vertebral fractures were observed in 473 participants. After adjusting for confounding variables, the spinal OA (≥ grade 2) was a significant predictor of incident vertebral fractures (hazard ratio, 1.52; 95% confidence interval: 1.19-1.93, p = 0.001). Using ROC analysis, the thresholds of lumbar BMD for incident vertebral fractures were 0.952 g/cm2 for patients with spinal OA and 0.753 g/cm2 for patients without spinal OA. The presence of spinal OA is a risk factor for incident vertebral fractures despite high lumbar BMD.

3D assessment of intervertebral disc degeneration in zebrafish identifies changes in bone density that prime disc disease

Back pain is a common condition with a high social impact and represents a global health burden. Intervertebral disc disease (IVDD) is one of the major causes of back pain; no therapeutics are currently available to reverse this disease. The impact of bone mineral density (BMD) on IVDD has been controversial, with some studies suggesting osteoporosis as causative for IVDD and others suggesting it as protective for IVDD. Functional studies to evaluate the influence of genetic components of BMD in IVDD could highlight opportunities for drug development and repurposing. By taking a holistic 3D approach, we established an aging zebrafish model for spontaneous IVDD. Increased BMD in aging, detected by automated computational analysis, is caused by bone deformities at the endplates. However, aged zebrafish spines showed changes in bone morphology, microstructure, mineral heterogeneity, and increased fragility that resembled osteoporosis. Elements of the discs recapitulated IVDD symptoms found in humans: the intervertebral ligament (equivalent to the annulus fibrosus) showed disorganized collagen fibers and herniation, while the disc center (nucleus pulposus equivalent) showed dehydration and cellular abnormalities. We manipulated BMD in young zebrafish by mutating sp7 and cathepsin K, leading to low and high BMD, respectively. Remarkably, we detected IVDD in both groups, demonstrating that low BMD does not protect against IVDD, and we found a strong correlation between high BMD and IVDD. Deep learning was applied to high-resolution synchrotron µCT image data to analyze osteocyte 3D lacunar distribution and morphology, revealing a role of sp7 in controlling the osteocyte lacunar 3D profile. Our findings suggest potential avenues through which bone quality can be targeted to identify beneficial therapeutics for IVDD.

Osteoarthritis and the incidence of fracture in the United Kingdom: a retrospective cohort study of 258,696 patients

OBJECTIVE

The goal of this study was to analyze the relationship between osteoarthritis and the incidence of fracture in men and women aged ≥18 years followed in general practices in the United Kingdom.

METHODS

This study included patients aged ≥18 years who had received an initial diagnosis of osteoarthritis in one of 256 general practices in the United Kingdom between January 1997 and December 2016 (index date). Patients without osteoarthritis were matched (1:1) to those with osteoarthritis by sex, age, index year, diabetes, dementia, corticosteroid therapy, and practice. For patients without osteoarthritis, the index date was a randomly selected visit date between 1997 and 2016. The association between osteoarthritis and the incidence of fracture was investigated using Kaplan-Meier curves and conditional Cox regression analyses.

RESULTS

This retrospective cohort study included 129,348 patients with osteoarthritis and 129,348 patients without osteoarthritis [60.1% women; mean (standard deviation) age 63.7 (14.0) years]. After 10 years of follow-up, 12.1% of individuals with osteoarthritis and 7.7% of those without osteoarthritis had suffered at least one fracture (log-rank P-value<0.001). There was a positive and significant association between osteoarthritis and fracture in the overall sample [hazard ratio (HR) = 1.55, 95% confidence interval (CI) = 1.50-1.60]. These findings were corroborated in all sex, age, and osteoarthritis joint site subgroups.

CONCLUSION

Intervention is urgently needed to reduce the risk of fracture in adults with osteoarthritis, and further research is warranted in order to gain more of an insight into the mediators involved in the relationship between osteoarthritis and fracture.

Sintered dicalcium pyrophosphate treatment attenuates estrogen deficiency-associated disc degeneration in ovariectomized rats

Background

Estrogen deficiency is associated with musculoskeletal disorders. Sintered dicalcium pyrophosphate (SDCP) is a novel antiosteoporotic agent. In this study, we examined its use for restoration of bone quality and attenuation of disc degeneration in ovariectomy rats.

Methods

Sixty female Sprague Dawley rats were randomly divided into 3 groups, namely sham group undergoing sham surgery, ovariectomy (OVX) group receiving an equivalent volume of isotonic sodium chloride solution, and OVX/SDCP group orally administered with 0.25 mg/mL SDCP. Animals were sacrificed at 3 and 6 months post ovariectomy and lumbar vertebrae and intervertebral discs were harvested. Bone mineral density, micro-computed tomography analysis, and biomechanical testing were performed to assess bone quality. Histological analysis with hematoxylin and eosin, Alcian blue, and Masson’s trichrome stain were conducted to determine disc degeneration. Immunohistochemistry and real-time PCR were carried out to measure the expressions of aggrecan, type I collagen, type II collagen, and MMP-1, MMP-3, and MMP-13.

Results

SDCP improved bone quality as observed by the results of increased bone mineral density and stiffness in OVX rats. The improvement in disc degeneration induced by estrogen withdrawal was associated with reduced gene expressions of MMPs and increased production of collagen type II.

Conclusion

SDCP prevents osteoporosis and ameliorates disc degeneration in OVX rats. It represents a favorable therapeutic agent for osteoporotic and osteoarthritic conditions in clinical practice.

High Bone Mass is associated with bone-forming features of osteoarthritis in non-weight bearing joints independent of body mass index

OBJECTIVES

High Bone Mass (HBM) is associated with (a) radiographic knee osteoarthritis (OA), partly mediated by increased BMI, and (b) pelvic enthesophytes and hip osteophytes, suggestive of a bone-forming phenotype. We aimed to establish whether HBM is associated with radiographic features of OA in non-weight-bearing (hand) joints, and whether such OA demonstrates a bone-forming phenotype.

METHODS

HBM cases (BMD Z-scores≥+3.2) were compared with family controls. A blinded assessor graded all PA hand radiographs for: osteophytes (0-3), joint space narrowing (JSN) (0-3), subchondral sclerosis (0-1), at the index Distal Interphalangeal Joint (DIPJ) and 1st Carpometacarpal Joint (CMCJ), using an established atlas. Analyses used a random effects logistic regression model, adjusting a priori for age and gender. Mediating roles of BMI and bone turnover markers (BTMs) were explored by further adjustment.

RESULTS

314 HBM cases (mean age 61.1years, 74% female) and 183 controls (54.3years, 46% female) were included. Osteophytes (grade≥1) were more common in HBM (DIPJ: 67% vs. 45%, CMCJ: 69% vs. 50%), with adjusted OR [95% CI] 1.82 [1.11, 2.97], p=0.017 and 1.89 [1.19, 3.01], p=0.007 respectively; no differences were seen in JSN. Further adjustment for BMI failed to attenuate ORs for osteophytes in HBM cases vs. controls; DIPJ 1.72 [1.05, 2.83], p=0.032, CMCJ 1.76 [1.00, 3.06], p=0.049. Adjustment for BTMs (concentrations lower amongst HBM cases) did not attenuate ORs.

CONCLUSIONS

HBM is positively associated with OA in non-weight-bearing joints, independent of BMI. HBM-associated OA is characterised by osteophytes, consistent with a bone-forming phenotype, rather than JSN reflecting cartilage loss. Systemic factors (e.g. genetic architecture) which govern HBM may also increase bone-forming OA risk.

The relationships between bone mineral density and radiographic features of hand or knee osteoarthritis in older adults: data from the Dong-gu Study

OBJECTIVE

The relationship between OA and osteoporosis has exhibited contradictory features over the past four decades. The aim of this study was to determine using separate analysis of the radiographic features of OA whether various radiographic features of OA were associated differently with BMD in the Korean elderly.

METHODS

Data were derived from the Dong-gu cohort; 2354 subjects were enrolled in the present cross-sectional study. Baseline characteristics, the BMDs of the lumbar spine and femoral neck measured by DXA, and X-rays of knees and hands were collected. A semi-quantitative grading system was used to estimate the severities of individual radiographic features. We adjusted for confounders using multiple linear regression modelling to analyse the relationships.

RESULTS

After adjustment for confounders, hand and knee OA total scores were negatively associated with the BMDs of the lumbar spine and femoral neck, except for the total knee OA score and lumbar spine BMD. In detail, hand osteophytes and sclerosis exhibited positive relationships with the BMDs of the lumbar spine and femoral neck, except for hand osteophytes and femoral neck BMD. On the contrary, however, knee joint space narrowing (JSN), hand JSN, and hand subchondral cysts were negatively associated with the BMD of the lumbar spine and femoral neck. Knee JSN and hand subchondral cysts exerted the greatest effects on BMD.

CONCLUSION

Separate analysis of the radiographic features of OA better reveals associations of OA with the BMD of the lumbar spine and femoral neck.

Osteoarthritis of the Distal Interphalangeal and First Carpometacarpal Joints is Associated with High Bone Mass in Women and Small Bone Size and Low Lean Mass in Men

Objective:

To determine if primary hand osteoarthritis (OA) is associated with abnormal bone and anthropometric traits.

Methods:

We used DXA to measure total body bone mineral density (BMD), femoral neck width (bone size) and total body lean and fat mass in 39 subjects with hand OA (primary DIP and/or CMC I) and 164 controls. Data are presented as mean Z-scores or Odds Ratios (OR) with 95% confidence intervals.

Results:

Women with hand OA had (compared to controls) higher BMD (0.5(0.1,0.9)) but similar bone size (-0.3(-0.8,0.2)), lean mass (0.3(-0.3,0.9)), fat mass (-0.1(-0.6,0.5)) and BMI (0.0(-0.6,0.6)). Men with hand OA had (compared to controls) similar BMD (-0.1(-0.7,0.6)), smaller bone size (-0.5(-1.1,-0.01)), lower lean mass (-0.6(-1.1,-0.04)), and similar fat mass (-0.2(-0.7,0.4)) and BMI -0.1(-0.6,0.6). In women, each SD higher BMD was associated with an OR of 1.8 (1.03, 3.3) for having hand OA. In men each SD smaller bone size was associated with an OR of 1.8 (1.02, 3.1) and each SD lower proportion of lean body mass with an OR of 1.9 (1.1, 3.3) for having hand OA.

Conclusion:

Women with primary DIP finger joint and/or CMC I joint OA have a phenotype with higher BMD while men with the disease have a smaller bone size and lower lean body mass.

Diametrical diseases reflect evolutionary-genetic tradeoffs: Evidence from psychiatry, neurology, rheumatology, oncology and immunology

Tradeoffs centrally mediate the expression of human adaptations. We propose that tradeoffs also influence the prevalence and forms of human maladaptation manifest in disease. By this logic, increased risk for one set of diseases commonly engenders decreased risk for another, diametric, set of diseases. We describe evidence for such diametric sets of diseases from epidemiological, genetic and molecular studies in four clinical domains: (i) psychiatry (autism vs psychotic-affective conditions), (ii) rheumatology (osteoarthritis vs osteoporosis), (iii) oncology and neurology (cancer vs neurodegenerative disorders) and (iv) immunology (autoimmunity vs infectious disease). Diametric disorders are important to recognize because genotypes or environmental factors that increase risk for one set of disorders protect from opposite disorders, thereby providing novel and direct insights into disease causes, prevention and therapy. Ascertaining the mechanisms that underlie disease-related tradeoffs should also indicate means of circumventing or alleviating them, and thus reducing the incidence and impacts of human disease in a more general way.

Evaluation of femoral neck bone mineral density and radiographic hand and knee osteoarthritis in a Korean elderly population

BACKGROUND

Reports on the relationship between osteoporosis and osteoarthritis (OA) have tended to disagree, especially in non-weight bearing joints such as the hand joints. We aimed to investigate the relationship between bone mineral density (BMD) and hand and knee OA in a general Korean elderly population.

METHODS

We evaluated femur neck BMD and the hand and knee radiographs of 143 men and 123 women over 65 years of age who participated in a population-based cohort study. The Kellgren-Lawrence criteria for grading OA were implemented, and grade 2 or higher were categorized as radiographic OA. BMD was compared according to the existence of radiographic OA in the hand and knee using analysis of covariance, and correlation analyses were performed to explore the relationship between BMD and radiographic OA grade.

RESULTS

After controlling for age and body mass index, there was no significant difference in BMD between participants with and without hand OA (p = 0.717 in male and p = 0.862 in female), between those with and without knee OA (p = 0.974 in male and p = 0.563 in female), and between those with only hand OA and those with only knee OA (p = 0.920 in male and p = 0.961 in female). Furthermore, there was no significant correlation between BMD and the radiographic OA grade of the hands (p = 0.182 in male and p = 0.897 in female) and knees (p = 0.245 in male and p = 0.098 in female).

CONCLUSIONS

In our cohort of the general Korean elderly population, no association was found between osteoporosis and OA, regardless of the weight bearing status of the joints.

Patients with hip osteoarthritis have a phenotype with high bone mass and low lean body mass

BACKGROUND

Although hip osteoarthritis (OA) is common, its etiology is poorly understood. Specifically, it is not known whether hip OA is associated with abnormal relationships among the anthropometric and musculoskeletal characteristics that are associated with OA in general.

QUESTIONS

We asked whether patients with primary hip OA have a phenotype with higher bone mineral density (BMD), higher BMI, larger skeletal size, lower lean body mass, and higher fat content.

MATERIAL AND METHODS

We included 30 women and 32 men (mean age, 66 years; range, 42-84 years) with primary hip OA and 96 women and 91 men as control subjects. Dual energy x-ray absorptiometry was used to measure total body BMD (g/cm(2)), femoral neck width (cm), fat and lean mass (%), and BMI (kg/m(2)). Z scores were calculated for each individual. Data are presented as means with 95% CI.

RESULTS

Women with hip OA had the following Z scores: total body BMD 0.6 (0.3, 1.0); BMI 0.6 (0.2, 1.0); femoral neck width 0.2 (-0.6, 1.0); percent total body lean mass -0.9 (-1.2, -0.5); and percent total body fat mass 0.6 (0.2, 0.9). Men with hip OA had the following mean Z scores: total body BMD 0.5 (0.0, 1.0); BMI 0.8 (0.3, 1.3); femoral neck width 0.4 (0.01, 0.9); percent total body lean mass -0.8 (-1.1, -0.5); and percent total body fat mass 0.5 (0.2, 0.8).

CONCLUSIONS

Women and men with idiopathic hip OA have a phenotype with higher BMD, higher BMI, proportionally higher fat mass, and proportionally lower lean body mass. Men also have a larger skeletal size.

CLINICAL RELEVANCE

A higher BMD may lead to a stiffer bone and a proportionally lower lean body mass to lower joint-protective ability, both traits probably predisposing for hip OA.

Bone mass and anthropometry in patients with osteoarthritis of the foot and ankle

BACKGROUND

Patients with hip and knee osteoarthritis (OA) have high bone mineral density (BMD) and high BMI. If the same accounts for patients with foot or ankle OA is unknown.

METHODS

We measured BMD and femoral neck (FN) width by dual-energy X-ray absorptiometry in 42 women and 19 men with idiopathic OA in the foot or ankle, and in 99 women and 82 men as controls.

RESULTS

Women with OA had significant higher BMI than controls. Women with OA had higher BMI-adjusted BMD (p<0.01) and smaller BMI-adjusted FN width (p<0.01) than controls. Men with OA had higher BMI adjusted-BMD (p<0.05) and smaller BMI-adjusted FN width (p<0.01) than controls.

CONCLUSION

Patients with OA in the foot or ankle have higher BMD and smaller bone size than being expected by their BMI. This phenotype may provide unfavourable forces across the joint and is hypothetically important for development of OA.

Hand osteoarthritis and bone loss: is there an inverse relationship?

An inverse relationship between osteoarthritis (OA) and bone loss has been supported in clinical research, but there has been little research on bioarchaeological skeletal remains. The current study examines 115 adults from a prehistoric hunter-gatherer population to aid in determining whether hand OA and bone loss are negatively correlated. OA lipping is scored on a four-point scale on left and right trapezia, MC1s, and MC2s and then analyzed with regard to their relationships with sex, age, right MC2 cortical index, and left and right MC1 robusticity, midshaft circumference, and midshaft diameter values. With sexes and ages combined, higher OA scores are found in individuals with greater midshaft diameters. However, lower cortical indices were found in individuals with higher right MC2 OA scores. The data presented tenuously support that bone loss is lower in individuals with more severe osteoarthritis, but age-related changes in bone deposition may make cortical index and other external shaft dimensions an unsuitable variable to examine this relationship.

Prevalence and sex difference of lumbar disc space narrowing in elderly chinese men and women: osteoporotic fractures in men (Hong Kong) and osteoporotic fractures in women (Hong Kong) studies

OBJECTIVE

Osteoporotic Fractures in Men (Hong Kong) and Osteoporotic Fractures in Women (Hong Kong) represent the first large-scale prospective population-based studies on bone health in elderly (age≥65 years) Chinese men (n=2,000) and women (n=2,000). We undertook the current study to investigate the prevalence of lumbar disc space narrowing in these subjects, and to identify the potential relationship between disc space narrowing and sex, bone mineral density (BMD), and other demographic and clinical data.

METHODS

On lumbar lateral radiographs, L1/L2-L4/L5 disc space was classified into 4 categories: 0=normal; 1=mild narrowing; 2=moderate narrowing; 3=severe narrowing. We compared demographic and clinical data between subjects with and those without total disc space narrowing scores≥3.

RESULTS

Disc space narrowing was more common in elderly women than in elderly men. The mean±SD disc space narrowing score for the 4 discs was 2.71±2.21 for men and 3.08±2.50 for women (P<0.0001). For the 3 age groups of 65-69 years, 70-79 years, and ≥80 years, the average disc space narrowing score increased with increasing age in both men and women, and to a greater degree in women than in men. The average disc space narrowing score differences between women and men were 0.12, 0.40, and 0.90, respectively, in the 3 age groups. For both men and women, a disc space narrowing score≥3 was associated with older age, higher spine and hip BMD, low back pain, and restricted leg mobility.

CONCLUSION

The prevalence and severity of disc space narrowing are higher in elderly women than in elderly men. With increasing age, disc space narrowing progresses at a greater rate in women than in men. A disc space narrowing score≥3 is associated with higher spine and hip BMD.

High bone mass is associated with an increased prevalence of joint replacement: a case-control study

Objective. Epidemiological studies have shown an association between OA and increased BMD. To explore the nature of this relationship, we examined whether the risk of OA is increased in individuals with high bone mass (HBM), in whom BMD is assumed to be elevated due to a primary genetic cause.

Methods. A total of 335 115 DXA scans were screened to identify HBM index cases (defined by DXA scan as an L1 Z-score of ≥+3.2 and total hip Z-score ≥+1.2, or total hip Z-score ≥+3.2 and L1 Z-score ≥+1.2). In relatives, the definition of HBM was L1 Z-score plus total hip Z-score ≥+3.2. Controls comprised unaffected relatives and spouses. Clinical indicators of OA were determined by structured assessment. Analyses used logistic regression adjusting for age, gender, BMI and social deprivation.

Results. A total of 353 HBM cases (mean age 61.7 years, 77% female) and 197 controls (mean age 54.1 years, 47% female) were included. Adjusted NSAID use was more prevalent in HBM cases versus controls [odds ratio (OR) 2.17 (95% CI 1.10, 4.28); P = 0.03]. The prevalence of joint replacement was higher in HBM cases (13.0%) than controls (4.1%), with an adjusted OR of 2.42 (95% CI 1.06, 5.56); P = 0.04. Adjusted prevalence of joint pain and knee crepitus did not differ between cases and controls.

Conclusion. HBM is associated with increased prevalence of joint replacement surgery and NSAID use compared with unaffected controls.

Relationship between hip bone mineral density and lumbar disc degeneration: a study in elderly subjects using an eight-level MRI-based disc degeneration grading system

PURPOSE

To study the relationship between hip bone mineral density (BMD), lumbar disc degeneration, and lumbar disc space narrowing in elderly subjects.

MATERIALS AND METHODS

The study cohort comprised 196 females and 163 males (age range, 67-89 years) with no age difference between the two groups. Anteroposterior total hip areal BMD was measured with DXA and lumbar spine MRI was acquired using a 1.5 Tesla scanner. Lumbar disc degeneration was assessed using an eight-level grading system wherein each grade represents a stepwise progression from normal disc to severe disc degeneration and disc space narrowing.

RESULTS

After controlling for the age effect, no significant relationship was observed between total hip T-score status and severity of disc degeneration. There was no significant difference in total hip BMD in the subjects with or without the disc space narrowing (P < 0.05). Female subjects are more likely to have a narrowed disc space than males at all levels, and being statistically significant at L3/4 and L4/5 levels, and with an overall significance of P = 0.007.

CONCLUSION

There was no association observed between hip BMD and lumbar disc degeneration. Elderly females were more likely to have a narrowed lumbar disc space than elderly males.

Serum resistin level is associated with radiographic changes in hand osteoarthritis: cross-sectional study

OBJECTIVE

The aim of this study was to determine whether adipokines such as adiponectin and resistin were related to radiographic outcomes in patients with hand osteoarthritis (OA).

METHODS

A total of 156 female subjects (46 controls, 60 non-radiographic hand OA, and 50 radiographic hand OA) were enrolled. We measured serum adiponectin and resistin concentrations using an enzyme-linked immunosorbent assay (ELISA). Radiographic hand OA was defined by the presence of a ≥2 Kellgren-Lawrence radiological grade after assessment for 20 joints of both hands. The association between radiographic hand OA and each adipokine was assessed using multivariate logistic regression models controlling for confounding clinical parameters.

RESULTS

Serum resistin levels in radiographic hand OA patients were higher than in non-radiographic hand OA and controls (p(adj)=0.020 and p(adj)=0.019, respectively), whereas there were no significant differences in serum adiponectin levels. The presence of radiographic changes in hand OA was shown to be dependent on serum resistin levels (p(adj)=0.028). Specifically, subchondral erosion in radiographic hand OA was associated with serum resisitin (p(adj)=0.028). However, there were no associations of serum adipokines with joint space narrowing, bony ankylosis, and cortical destruction.

CONCLUSIONS

This study suggests that resistin is involved in radiographic changes in hand OA, and that adipokines contribute to pathogenesis in radiographic outcomes in hand OA.

Relationship between gender, bone mineral density, and disc degeneration in the lumbar spine: a study in elderly subjects using an eight-level MRI-based disc degeneration grading system

The study cohort comprised 196 females and 163 males. Lumbar spine bone mineral density (BMD) and magnetic resonance imaging (MRI) were acquired. Females had more severe disc degeneration than males. Lumbar spine lower BMD was associated with less severe disc degeneration. Lumbar disc spaces were more likely to be narrower when vertebral BMD was higher.

INTRODUCTION

The purpose of this paper is to study the relationship between gender, BMD, and disc degeneration in the lumbar spine.

METHODS

The study cohort comprised 196 females and 163 males (age range 67-89 years) with no age difference between the two groups. Lumbar spine BMD was measured with dual X-ray densitometry, and MRI was acquired at 1.5 T. A subgroup of 48 males had additional lumbar vertebral quantitative computerized tomography densitometry. Lumbar disc degeneration was assessed using a MRI-based eight-level grading system.

RESULTS

Female subjects had more severe disc degeneration than male subjects. After removing age effect, a positive trend was observed between T-score and severity of lumbar disc degeneration. This was significant in female subjects while not significant in male subjects. Lumbar disc spaces were more likely to be narrowed when vertebral BMD was higher. These observations were more significant in the midlumbar region (L3/4 and L4/5) and less so at the thoracolumbar junction.

CONCLUSION

Female subjects tended to have slightly more severe lumbar disc degeneration than male subjects. Lower lumbar spine BMD was associated with less severe disc degeneration.

Osteogenic potential and responsiveness to leptin of mesenchymal stem cells between postmenopausal women with osteoarthritis and osteoporosis

The aim of this study was to compare the osteogenic potential and responsiveness to leptin of mesenchymal stem cells (MSCs) from bone marrow between postmenopausal women with osteoarthritis (OA) and osteoporosis (OP). MSCs of the proximal femur from OA and OP donors were cultured under control and different experimental mediums. After verifying the availability of primary cells, their osteogenic potential and responsiveness to leptin were compared between two groups. Similar patterns of cell growth were shown in both OA and OP groups. However, after the sixth passage, the viability of undifferentiated cells decreased more in OP than in OA donors. Under the same osteogenic supplements condition, the mRNA expression of osteogenesis-specific genes, osteocalcin (OC) and alkaline phosphatase (ALP) were higher in OA group. Comparison of bone matrix mineralization was parallel to that of mRNA expression. The level of bone-specific ALP (BAP) was higher in cells from donors with OA, whereas osteoprotegerin (OPG) was higher in OP group. This difference in BAP expression proved to be insignificant after the administration of leptin. Although leptin upregulated the expression of OPG, a significant difference still existed between OA and OP. In conclusion, differential osteogenic potential and responsiveness to leptin of MSCs were noted between postmenopausal women with OA and OP. Differential biological behavior of MSCs seems to be partly related to the different distribution of bone mass between OA and OP populations.

Lower bone mineral density of forearm in postmenopausal patients with radiographic hand osteoarthritis

The association between clinical parameters and forearm bone mineral density (BMD) in postmenopausal females with radiographic hand OA has not been determined. We investigated the difference in forearm BMD between radiographic hand OA and non-radiographic hand OA, and also the association between clinical parameters of patients and the level of forearm BMD. A total of 180 postmenopausal patients with hand OA were enrolled in this study. We classified them into two groups according to the Kellgren-Lawrence (K-L) radiological grade, one with radiographic hand OA (K-L grade > or = 2) and the other with non-radiographic OA (K-L grade < 2) as controls. The number of nodal joints, swollen joints and tender joints were determined in the physical examination, and measures of BMD (g/cm(2)), Australian Canadian (AUSCAN) OA hand index, grip strength, pinch strength, and visual analogue scale (VAS) were also estimated. Patients with radiographic hand OA had lower distal radius BMD when compared with controls (0.35 +/- 0.06 vs. 0.40 +/- 0.05, P < 0.001). After adjusting for variables such as age, menopausal duration, number of nodal joints, and AUSCAN function index, the difference in BMD between the two groups was also significantly different (0.35 +/- 0.04 vs. 0.38 +/- 0.04, P < 0.001). For analysis of risk factors for forearm BMD in hand OA, age and K-L OA grade in total hand OA are considered risk factors, whereas age and menopause duration contribute to the forearm BMD in radiographic hand OA patients (P < 0.001, P = 0.002, respectively). The development of osteoporosis at the distal radius in radiographic hand OA is associated with older age (OR = 1.216, P = 0.002), lower BMI (OR = 0.777, P = 0.004) and lower stiffness in the AUSCAN OA index (OR = 0.505, P = 0.003). This study shows that the BMD levels of the distal radius in patients with radiographic hand OA are significantly lower when compared to those of controls. Forearm BMD levels are positively associated with age and K-L radiological grade in total hand OA, whereas age and menopausal duration are closely related with radiographic hand OA. The presence of osteoporosis in the distal radius in radiographic hand OA may be influenced by age, BMI, and stiffness on the AUSCAN index.

Biomarkers, type II collagen, glucosamine and chondroitin sulfate in osteoarthritis follow-up: the "Magenta osteoarthritis study"

Background

The purpose of the present study was to determine relationship between disease activity, systemic markers of cartilage degradation, urinary C-terminal cross-linking telopeptides of type II collagen (uCTX-II), and bone degradation, urinary C-terminal cross-linking telopeptides of type I collagen (uCTX-I), structural progression of osteoarthritis (OA) and potential therapeutic efficacy of type II collagen (COLLII) in combination with glucosamine and chondroitin sulfate (GC).

Materials and methods

An observational retrospective study, 1-year follow-up, on 104 patients with OA (nodular osteoarthritis of the hand, erosive osteoarthritis of the hand, EOA, osteoarthritis of the knee or hip) who were treated with GC or glucosamine, chondroitin sulfate and collagen type II (GCC). The following information was collected at entry: demographics, BMI, characteristics of OA, patient global assessment (VAS), C-terminal cross-linking telopeptides of collagen types I (uCTX-I) and II (uCTX-II) and radiographs. After 6 months: VAS, uCTX-I and uCTX-II. After 1 year: VAS, uCTX-I, uCTX-II and radiographs.

Results

After 6 months and 1 year of treatment VAS, uCTX-I and uCTX-II mean values were significantly lower than the baseline. 57 were treated with GCC and 47 with GC. The group that received GCC showed a similar VAS mean value after 6 months and 1 year when compared with the group treated with GC. uCTX-I and uCTX-II mean level was lower in the group treated with GCC (P < 0.05). Radiological score (Kellgren and Lawrence summarized score for hands) after 1 year showed a reduced progression compared to the baseline in the hand osteoarthritis group, especially after GCC treatment (P < 0.05). Finally, uCTX-I has better correlation with radiological score and with GC in the EOA subgroup (Pearson index: R = 0.44).

Conclusions

(a) uCTX-I and uCTX-II proved to be useful biomarkers in OA monitoring; (b) uCTX-I is better correlated with hand EOA and could represent a potential further marker to assess the evolution of EOA bone damage; (c) GC slow down OA progression; (d) finally COLLII could represent a further protective factor in OA cartilage.

Differential bone metabolism between postmenopausal women with osteoarthritis and osteoporosis

A comparative study of bone metabolism between postmenopausal women with osteoarthritis and osteoporosis showed that differential levels of bone remodeling markers, leptin, free leptin index, and osteoprotegerin might partly contribute to the proposed inverse relationship in bone mass between postmenopausal women with osteoarthritis and osteoporosis.

INTRODUCTION

Osteoarthritis (OA) and osteoporosis (OP) are two common disorders affecting the quality of life in the elderly. The association between OA and OP has always been debated. The objective of this study was to compare bone metabolism between postmenopausal women with OA and OP.

MATERIALS AND METHODS

A total of 120 postmenopausal women with OA and OP (n = 60, respectively) were included in this comparative study. Anthropometric parameters and BMD at the spine and the proximal femur were measured. Serum leptin, soluble leptin receptor (sLR), osteoprotegerin (OPG), and bone remodeling markers, including bone-specific alkaline phosphatase (BALP), osteocalcin (OC), deoxypyridinoline cross-links (DPD), and cross-linked N-telopeptides of type I collagen (NTX), were quantified with commercial ELISA or EIA kits. Free leptin index (FLI) was also calculated by the ratio between serum leptin and sLR levels.

RESULTS

Postmenopausal women with OA had higher body weight, body mass index, fat mass, and percentage of fat than those suffered from OP. Compared with the patients in OP group, the patients in OA group had significantly higher BMD values at all sites measured. Higher serum leptin and FLI and lower OPG levels were shown in the OA group (leptin: 31.22 +/- 6.4 versus 26.50 +/- 9.27 ng/ml, p < 0.001; FLI: 3.20 +/- 1.02 versus 2.50 +/- 0.95, p < 0.05; OPG: 4.75 +/- 1.97 versus 6.96 +/- 2.75 pM, p < 0.001), whereas lower serum OC and higher urine DPD were noted in the OP group (OC: 16.45 +/- 8.45 versus 13.06 +/- 6.25 ng/ml, p < 0.05; DPD: 10.83 +/- 7.12 versus 15.29 +/- 6.65 nM BCE/mM Cr, p < 0.001). Serum OPG levels negatively correlated with BMD at all sites assessed. However, no correlation was found between leptin and BMD. Only in the OA group di positive correlations exist between FLI and Z-score at the femoral neck and Ward's triangle region. After stepwise regression analysis, it was found that differential factors were able to predict the variance of BMD at different sites to a certain extent.

CONCLUSIONS

Our study suggests that there are significant differences in bone metabolism between postmenopausal women with OA and OP and provides evidence for the inverse relationship between OA and OP. Differential levels of bone remodeling markers, leptin, FLI, and OPG may partly contribute to the proposed inverse relationship. Roles of leptin and its soluble receptor in bone metabolism regulation should be explored further.

Early identification of radiographic osteoarthritis of the hip using an active shape model to quantify changes in bone morphometric features: can hip shape tell us anything about the progression of osteoarthritis?

OBJECTIVE

Few methods exist to measure the progression of osteoarthritis (OA) or to identify people at high risk of developing OA. Striking radiographic changes include deformation of the femoral head and osteophyte growth, which are usually measured semiquantitatively following visual assessment. In this study, an active shape model (ASM) of the proximal femur was used to determine whether morphologic changes to the bone could be quantified and used as a marker of hip OA.

METHODS

One hundred ten subjects who had no signs of radiographic hip OA at baseline (Kellgren/Lawrence [K/L] scores 0-1) were selected from the Rotterdam Study cohort of subjects ages > or = 55 years. To measure the progression of OA, subjects were followed up with radiographic assessment after 6 years. At the 6-year followup, 55 subjects had established OA (K/L score 3), and in 12 of these OA subjects, the progression of the disease required a total hip replacement (THR). Age- and sex-matched control subjects had a K/L score of 0 at followup. Using the ASM, subjects were assessed for shape changes in the femoral head and neck before, during, and after the development of radiographic OA. Scores of shape variance, or mode scores, were assigned for 10 modes of variation in each subject, and differences in mode scores were determined.

RESULTS

During followup, significant changes in shape of the proximal femur occurred within the OA group from baseline to followup (P < 0.0001 for mode 1 and P = 0.002 for mode 6) but not within the control group. At baseline (all subjects having K/L scores 0-1), there were significant differences in mode 6 between the OA group and the control group (P = 0.020), and in modes 3 and 6 between the OA subjects who underwent THR and the remaining OA subjects (P = 0.012 and P = 0.019, respectively).

CONCLUSION

Compared with traditional scoring methods, the ASM can be used more precisely to quantify the deforming effect of OA on the proximal femur and to identify, at an earlier stage of disease, those subjects at highest risk of developing radiographic OA or needing a THR. The ASM may therefore be useful as an imaging biomarker in the assessment of patients with hip OA.

Effect of prayer on osteoarthritis and osteoporosis

Prayer is one kind of worship that is composed of repetitive action during praying in Islam. The prayer is performed five times a day, every Friday, bairams and death ceremonies. The aim of this study is to search the role of this repetitive action on knee, hip osteoarthritis and osteoporosis. Forty-six patients who had been performing the prayer at least for 10 years, and 40 patients who had not performed the prayer, were included in this prospective study. Each patient was evaluated with standard questionnaire form, joint examination was done and various laboratory parameters were studied. Anterior-posterior radiography of the pelvis and weight-bearing knees of each patient were examined. Each film was evaluated by two investigators separately and first scored by using Kellgren and Lawrence (K&L) scale, then the width of the joint space of hips and knees were measured directly using a steel ruler and recorded to the nearest half millimeter. Bone mineral density (BMD) of lumbar spine and femur was measured. Patients having Heberden's nodes, Bouchard's nodes, and carpometacarpal disease were frequent in worshiper group. Joint space width measurements and assessment according to K&L scale did not differ between worshipers and non-worshipers. BMD of lumbar spine was decreased in worshipers and also decreased with patients having Heberden's nodes, Bouchard's nodes, female gender and age. Prayer has no effect on knee and hip osteoarthritis, and may be related with hand osteoarthritis. It seems to have negative effect on lumbar BMD, but further investigations are needed.

Bone mineral density in patients with hand osteoarthritis compared to population controls and patients with rheumatoid arthritis

OBJECTIVES

Several studies have revealed increased bone mineral density (BMD) in patients with knee or hip osteoarthritis, but few studies have addressed this issue in hand osteoarthritis (HOA). The aims of this study were to compare BMD levels and frequency of osteoporosis between female patients with HOA, rheumatoid arthritis (RA) and controls aged 50-70 years, and to explore possible relationships between BMD and disease characteristics in patients with HOA.

METHODS

190 HOA and 194 RA patients were recruited from the respective disease registers in Oslo, and 122 controls were selected from the population register of Oslo. All participants underwent BMD measurements of femoral neck, total hip and lumbar spine (dual-energy x ray absorptiometry), interview, clinical joint examination and completed self-reported questionnaires.

RESULTS

Age-, weight- and height-adjusted BMD values were significantly higher in HOA versus RA and controls, the latter only significant for femoral neck and lumbar spine. The frequency of osteoporosis was not significantly different between HOA and controls, but significantly lower in HOA versus RA. Adjusted BMD values did not differ between HOA patients with and without knee OA, and significant associations between BMD levels and symptom duration or disease measures were not observed.

CONCLUSION

HOA patients have a higher BMD than population-based controls, and this seems not to be limited to patients with involvement of larger joints. The lack of correlation between BMD and disease duration or severity does not support the hypothesis that higher BMD is a consequence of the disease itself.

Are bone losers distinguishable from bone formers in a skeletal series? Implications for adult age at death assessment methods

Clinical studies indicate that genetic factors play a crucial role in primary osteoarthritis and osteoporosis. In addition, it has been suggested that these two diseases are inversely related. Within a population, one can find two sub-groups: the "bone formers" and the "bone losers". The changes to the joint surfaces used to assess adult age at death are related to the loss of bone substance and to bone formation (osteophytes). The modification of these indicators with age differs between bone formers and bone losers. Therefore, age-at-death assessment methods should make use of two standards, one for each sub-group. A preliminary study examining the possibility of distinguishing those who lose cortical bone from those who show signs of bony formation was conducted on a series of skeletons from Portugal, dating to the end of 19th century and the beginning of the 20th. Bone loss was evaluated using the cortical index (CI) of the second metacarpal on X-rays. The presence of osteophytes on dry bones was assessed macroscopically. Our study indicates that females' CI decreases with age, whereas the presence of osteophytes is strongly related to age in both sexes. But we have failed to find the inverse relationship between osteophytes and bone loss. Our study, however, shows that within a population, some individuals are not likely to develop osteophytes.

Epidemiology of Osteoporosis in Rheumatic Diseases

Much work has been directed at establishing the impact of osteoporosis and related fragility fractures in rheumatic diseases. Several cross-sectional studies reported that disability and reduced motility that are due to functional impairment are among the most important determinants of bone loss in different rheumatic diseases. At the same time, longitudinal studies have confirmed the detrimental effect of uncontrolled disease activity on bone density. In this perspective, the suppression of inflammation probably remains the main concern when considering treatment options. Besides these variables, pharmacologic agents that are used commonly in the treatment of these conditions probably have an adjunctive effect on bone loss in rheumatic patients. Large epidemiologic studies have demonstrated clearly that patients who have RA, SLE, or AS are at an increased risk for fragility fractures. Further studies are required to investigate the effective impact of osteoporosis and fragility fractures in other rheumatic diseases, and to define the relationship between OA and osteoporosis. A better appreciation of the impact and mechanisms of osteoporosis in rheumatic diseases by rheumatologists represents a clinical challenge; however, a greater understanding of this frequent complication will improve the quality of health care and the lives of patients who have rheumatic diseases.

Osteoporosis and bone metabolism in postmenopausal women with osteoarthritis of the hand

OBJECTIVE

Osteoarthritis and osteoporosis are two major health problems affecting postmenopausal women. Epidemiological observations seem to demonstrate a possible inverse relationship between osteoarthritis and osteoporosis. Erosive osteoarthritis (EOA) of the hand is a destructive form of primary osteoarthritis. This study evaluated bone mineral density and bone metabolism changes in erosive and nonerosive hand osteoarthritis women.

DESIGN

Fifty-five women (mean age, 59 years; body mass index, 23 +/- 1.4 kg/m) who had been postmenopausal for an average of 9 years and who presented with hand osteoarthritis according to American College of Rheumatology criteria were enrolled in the study; 15 women showed clinical and radiological evidence of hand EOA. Twenty women matched for age, age at menopause, and body mass index formed the control group. Bone mineral density (g/cm) was measured at the hip and lumbar spine using dual-energy x-ray absorptiometry. Serum and urinary calcium and phosphate, serum 25-hydroxyvitamin D, parathyroid hormone, osteocalcin, and urinary breakdown products of bone matrix (CrossLaps) were analyzed.

RESULTS

Women with hand EOA had a statistically significant lower T- and Z-score L2-L4 value than non-hand EOA women and controls (P < 0.01). Moreover, postmenopausal women with hand EOA had higher significant percentage of osteoporosis at lumbar spine when compared with non-hand EOA postmenopausal women and controls. Any statistically significant difference in osteocalcin and CrossLaps serum levels was noted among women with hand EOA, hand osteoarthritis, and controls.

CONCLUSIONS

Our data suggest that postmenopausal women with clinical and radiological EOA are at risk for development of osteoporosis.

Disc space narrowing as a new risk factor for vertebral fracture: the OFELY study

OBJECTIVE

In a previous cross-sectional analysis, we found a positive association between disc space narrowing (DSN) and vertebral fracture. The aim of the present study was to analyze prospectively the risk of vertebral and nonvertebral fractures in women with spine osteoarthritis (OA).

METHODS

Using radiographs, spine OA was evaluated in 634 postmenopausal women from the OFELY (Os des Femmes de Lyon) cohort (mean+/-SD age 61.2+/-9 years). Prevalence and severity of spine OA were assessed by scoring osteophytes and DSN. Incidental clinical fractures were prospectively registered during annual followup, and vertebral fractures were evaluated by radiography every 4 years.

RESULTS

During an 11-year followup, fractures occurred in 121 women, including 42 with vertebral fractures. No association was found between osteophytes and the risk of fracture. In contrast, DSN was associated with an increased risk of vertebral fractures but not of nonvertebral fractures. After adjusting for confounding variables, the presence of DSN was associated with a marked increased risk of vertebral fractures, with an odds ratio of 6.59 (95% confidence interval 1.36-31.9). In addition, 95% of incident vertebral fractures were located above the disc with the most severe narrowing.

CONCLUSION

This longitudinal study shows that, despite a higher bone mineral density (BMD), women with spine OA do not have a reduced risk of fracture and that DSN is significantly associated with vertebral fracture risk. The location of DSN and of incident vertebral fractures suggests that disc degeneration impairs the biomechanics of the above spine, which leads to the increased risk of vertebral fractures, independent of BMD. We suggest that DSN is a newly identified risk factor for vertebral fracture that should be taken into consideration when assessing vertebral fracture risk in postmenopausal women.

Das gemeinsame Auftreten von Osteoporose und Arthrose und der Nutzen der Knochenstoffwechselmarker

OBJECTIVE

Increasing bone mineral density (BMD) has been found in several studies in patients with osteoarthritis. Therefore, many clinicians deny the simultaneous occurrence of osteoporosis (OP) and osteoarthritis (OA). Because of our clinical impression however, we suggested that we have to consider a common occurrence. Furthermore, the value of markers of bone turn over with a view to early diagnosis of OP and or as an assessment for bone metabolism in OA is still a matter debate and their clinical use has not been clearly defined in the management of the individual patient.

METHOD

The BMD of the lumbar spine and the proximal femur of 119 OA patients (83 postmenopausal female patients aged 50-83 and 35 male patients aged 36-86 years) who subsequently required hip or knee replacements, but were otherwise healthy, were measured by dual energy X-ray absorption (DXA), Hologic QDR-2000. We also measured biochemical markers of bone turn over, i. e., CICP, ICTP, DPD, PTH, estrogen, testosterone, bAP, hydroxy vitamin D and the normal blood count.

RESULTS

There was a high occurrence of a low BMD among the patients. A total of 28.9% of women were affected by OP and 52.9% by osteopoenie. This reflects the normal distribution of OP in the female population. Of the male patients 20% had OP and 38.8% osteopoenie. This is astonishing high. Age proved to be a significant factor in the degree of BMD. An association between disuse osteoporosis and degree of BMD in the OA affected joint could not be proven. The use of the biochemical markers for an earlier diagnosis or to assess bone metabolism in OP and OA was not possible.

CONCLUSION

We can not support the hypotheses that OA prevents OP. Moreover, the occurrence of OP in our study reflected the incidence of OP in the average female and the astonishingly high incidence in the male population; however does not mean that the two conditions are mutually exclusive. We did not find that the biochemical markers of bone turn over could deliver additional information with respect to bone metabolism and an earlier diagnosis of OP.

Haplotypes of the low-density lipoprotein receptor-related protein 5 (LRP5) gene: are they a risk factor in osteoarthritis?

OBJECTIVE

Several genome-wide scans have revealed an osteoarthritis (OA)-susceptibility locus on chromosome 11q in close proximity to the low-density lipoprotein receptor-related protein 5 (LRP5) gene. The regulation of bone mass is under the control of LRP5 and since increased bone mass is thought to play a role in the pathology of OA we examined LRP5 polymorphisms and haplotypes to determine if variants of this locus may predispose to OA.

METHODS

A UK control population of 187 individuals was examined for five commonly occurring polymorphisms against a cohort of 158 DNAs from patients with knee OA. An additional UK cohort was also examined to confirm the findings of the first study; this second group consisted of 110 knee OA patients. Haplotype analysis was also performed on patient and control DNAs.

RESULTS

A study of individual polymorphisms revealed no association with disease. However, haplotype analysis of the initial two populations revealed a common haplotype (C-G-C-C-A) that provided a 1.6-fold increased risk of OA (P(c)=0.021). The data obtained from the second cohort confirmed the initial findings, with a 1.6-fold increased risk observed within this cohort for the risk haplotype (P=0.012).

CONCLUSIONS

A closer investigation of LRP5 and associated Wnt signalling molecules in OA will help determine disease aetiology and the development of novel treatment strategies that specifically target the bone compartment.

Disc space narrowing is associated with an increased vertebral fracture risk in postmenopausal women: the OFELY Study

We have analyzed the relationship between spine osteoarthritis and fractures in the OFELY cohort. Despite a higher BMD associated with spine OA, the risk of fragility fractures is not reduced. Disc space narrowing is associated with an increased risk of vertebral fracture. These data indicate that the risk of osteoporotic fracture should not be underestimated in women with spine OA.

INTRODUCTION

Although osteoarthritis (OA) and osteoporosis both increase with age, their co-existence is uncommon. A higher BMD in OA is well documented, but a reduction of the fracture risk is still controversial. Our objective was to analyze the risk of fracture in postmenopausal women with spine OA.

MATERIALS AND METHODS

In a cross-sectional study, spine OA was evaluated by lateral radiographs according to the method of Lane, and BMD was measured by DXA in 559 postmenopausal women from the OFELY cohort (mean age, 68 +/- 8 years; range, 58-94 years) 8 years after their inclusion into the study. Previous fragility fractures, all confirmed by radiographs, were prospectively registered during the annual follow-up for 8 years, and vertebral fractures were evaluated with spine radiographs. Severity of OA was assessed by scoring on osteophytes and disc narrowing on a four-point scale from 0 (normal) to 3 (severe) and graded as 0 (normal), 1 (mild osteophyte and/or narrowing), or 2 (moderate or severe osteophyte and/or narrowing).

RESULTS

Osteophytes and disc narrowing were present in 75% and 64%, respectively, of women at the lumbar spine and in 88% and 51%, respectively, at the thoracic spine, increasing with age. BMD of the spine, hip, and whole body increased with the severity of osteophytosis, whereas severity of narrowing was associated with a higher BMD only at the spine. Ninety-six fractures, including 48 vertebral fractures, occurred before OA assessment. No significant association was found between spine OA and all fragility fractures. In contrast, disc narrowing was associated with an increased risk of vertebral fracture with an odds ratio (95% CI) of 3.2 (1.1-9.3) after adjusting for age, body mass index, and BMD. The risk of vertebral fracture increased with the severity of disc narrowing. In comparison with the score 0, the odds ratio increased from 2.8 (0.9-8.7) to 4.6 (1.2-16.9) in women with mild to severe disc narrowing score.

CONCLUSIONS

Despite a higher BMD, women with spine OA do not have a reduced risk of fracture. Disc narrowing is associated with a significant increased vertebral fracture risk.

Relationship between osteopenia and lumbar intervertebral disc degeneration in ovariectomized rats

Ovariectomy (OVX) can cause bone loss in rats, but little is known about how it also induces lumbar intervertebral disc degeneration (LVD). This study investigated how estrogen deficiency affected intervertebral discs in OVX rats. Thirty 3-month-old female Sprague-Dawley rats were divided randomly into three equal groups. The baseline control group (BL) was killed at the beginning of the experiment. An ovariectomy was performed in 10 rats (OVX group) and another group of 10 rats was subjected to a sham surgery (Sham group). The OVX rats were untreated after the surgery to allow for the development of moderate osteopenia. Bone mineral density (BMD) measurement and bone histomorphometric analysis were applied to the segments of lumbar spines in all rats killed 6 months after surgery. The pathological changes of intervertebral discs were observed and the degree of LVD was scored by a histological scoring system. The BMD of the spines (L3-L5) in the OVX group decreased significantly compared with the Sham group. The bone volume indices in the OVX group were significantly lower, but the bone turnover rate parameters were significantly higher than those in the Sham group (P < 0.01). The histological scores for LVD in the OVX group were significantly higher than those in the Sham group (P < 0.01). There was a significant negative correlation between the BMD and Grade II discs in the OVX rats (P = 0.042). In conclusion, LVD occurs in the OVX rats and the degeneration of cartilage end plates may be a pathogenic factor in disc degeneration.

Osteoarthritis and osteoporosis: clinical and research evidence of inverse relationship

The etiology of osteoporosis (OP) and osteoarthritis (OA) is multifactorial: both constitutional and environmental factors, ranging from genetic susceptibility, endocrine and metabolic status, to mechanical and traumatic injury, are thought to be involved. When interpreting research data, one must bear in mind that pathophysiologic factors, especially in disorders associated with aging, must be regarded as either primary or secondary. Therefore, findings in end-stage pathology are not necessarily the evidence or explanation of the primary cause or event in the diseased tissue. Both aspects of research are important for potentially curative or preventive measures. These considerations, in the case of our topic--the inverse relationship of OP and OA--are of particular importance. Although the inverse relationship between two frequent diseases associated with aging, OA and OP, has been observed and studied for more than 30 years, the topic remains controversial for some and stimulating for many. The anthropometric differences of patients suffering from OA compared with OP are well established. OA cases have stronger body build and are more obese. There is overwhelming evidence that OA cases have increased BMD or BMC at all sites. This increased BMD is related to high peak bone mass, as shown in mother-daughter and twin studies. With aging, the bone loss in OA is lower, except when measured near an affected joint (hand, hip, knee). The lower degree of bone loss with aging is explained by lower bone turnover as measured by bone resorption-formation parameters. OA cases not only have higher apparent and real bone density, but also wider geometrical measures of the skeleton, diameters of long bones and trabeculae, both contributing positively to better strength and fewer fragility fractures. Not only is bone quantity in OA different but also bone quality, compared with controls and OP cases, with increased content of growth factors such as IGF and TGFbeta, factors required for bone repair. Furthermore, in vitro studies of osteoblasts recruited from OA bone have different differentiation patterns and phenotypes. These general bone characteristics of OA bone may explain the inverse relationship OA-OP and why OA cases have fewer fragility fractures. The role of bone, in particular subchondral bone, in the pathophysiology, initiation and progression of OA is not fully elucidated and is still controversial. In 1970, it was hypothesized that an increased number of microfractures lead to an increase in subchondral bone stiffness, which impairs its ability to act as a shock absorber, so that cartilage suffers more. Although subchondral bone is slightly hypomineralized because of local increased turnover, the increase in trabecular number and volume compensates for this, resulting in a stiffer structure. There is also some experimental evidence that osteoblasts themselves release factors such as metalloproteinases directly or indirectly from the matrix, which predispose cartilage to deterioration. Instead, the osteoblast regenerative capacity of bone in OP is compromised compared with OA, as suggested by early cell adhesion differences. The proposition that drugs which suppress bone turnover in OP, such as bisphosphonates, may be beneficial for OA is speculative. Although bone turnover in the subchondral region of established OA is increased, the general bone turnover is reduced. Further reduction of bone turnover, however, may lead to overmineralized (aged) osteons and loss of bone quality, resulting in increased fragility.

Appendicular bone mass and knee and hand osteoarthritis in Japanese women: a cross-sectional study

BACKGROUND

It has been reported that there is an inverse association between osteoarthritis (OA) and osteoporosis. However, the relationship of bone mass to OA in a Japanese population whose rates of OA are different from Caucasians remains uncertain.

METHODS

We studied the association of appendicular bone mineral density (second metacarpal; mBMD) and quantitative bone ultrasound (calcaneus; stiffness index) with knee and hand OA among 567 Japanese community-dwelling women. Knee and hand radiographs were scored for OA using Kellgren-Lawrence (K/L) scales. In addition, we evaluated the presence of osteophytes and of joint space narrowing. The hand joints were examined at the distal and proximal interphalangeal (DIP, PIP) and first metacarpophalangeal/carpometacarpal (MCP/CMC) joints.

RESULTS

After adjusting for age and body mass index (BMI), stiffness index was significantly higher in women with K/L scale, grade 3 at CMC/MCP joint compared with those with no OA. Adjusted means of stiffness index and mBMD were significantly higher in women with definite osteophytes at the CMC/MCP joint compared to those without osteophytes, whereas there were no significant differences for knee, DIP and PIP joints. Stiffness index, but not mBMD, was higher in women with definite joint space narrowing at the CMC/MCP joint compared with those with no joint space narrowing.

CONCLUSIONS

Appendicular bone mass was increased with OA at the CMC/MCP joint, especially among women with osteophytes. Our findings suggest that the association of peripheral bone mass with OA for knee, DIP or PIP may be less clearcut in Japanese women than in other populations.

Peak bone mass is increased in the hip in daughters of women with osteoarthritis

The mechanism behind the inverse association between osteoporosis and osteoarthritis shown in large epidemiological studies remains unclear. Because both diseases often demonstrate a family history, the objective of the present study was to compare peak bone density in daughters categorized according to the presence or absence of hand osteoarthritis in their mothers. Radiographs of the hands were obtained in women aged 50-75 years from a well-defined community population group. X-rays were graded for hand osteoarthritis (OA) using the Kellgren and Lawrence criteria. In 60 daughters (mean age 33.6 years) of these women, bone mineral density (BMD) was measured at five regions of the hip and lumbar spine and quantitative ultrasound (QUS) at the calcaneus. Daughters whose mothers had hand OA (i.e., OA at either the carpometacarpal [CMC] or distal interphalageal [DIP] joints) had significantly higher mean BMD, when adjusted for body mass index (BMI) (5.1%-8.1%, p < 0.05), at all hip regions except the trochanter. However, differences in lumbar BMD and calcaneal QUS were not statistically significant. In multiple regression analysis, maternal hand OA status was found to be a significant predictor of daughters' hip BMD when daughters' BMI and mothers' BMD were included in the model. These findings suggest that the observation of higher BMD in older patients with OA may be due in part to achievement of a higher peak bone mass at some sites.

The relationship of bone density and fracture to incident and progressive radiographic osteoarthritis of the knee: the Chingford Study

OBJECTIVE

Investigators performing cross-sectional studies have reported small increases in bone mineral density (BMD) in subjects with osteoarthritis (OA). This study was undertaken to examine the association of bone mass with incident and progressive disease and to determine whether prior fractures influence the development of OA.

METHODS

Eight hundred thirty women had repeat knee radiographs 48 months from baseline. All radiographs were graded on the presence or absence of osteophytes and joint space narrowing (JSN). Incident knee OA was defined as new disease in the 715 women without knee OA at baseline. Progression was a change of at least one grade in the 115 women with baseline knee OA. All women underwent bone densitometry of the lumbar spine and hip. Rates of subsequent incident OA were compared between fracture groups.

RESULTS

The 95 women with incident knee osteophytes had significantly higher baseline spine BMD (1.01 gm/cm2 versus 0.95 gm/cm2, or 6.3%; P = 0.002) and significantly higher hip BMD (0.79 gm/cm2 versus 0.76 gm/cm2, or 3.9%; P = 0.02) than those without incident disease. For the 33 women whose osteophytes progressed, no difference was seen compared with nonprogressors in spine BMD, but hip BMD was modestly reduced (-2.5%). The 81 women who had incident JSN had nonsignificantly higher baseline spine BMD (3.0%), while no difference was seen for the 30 women whose JSN had progressed. For hip BMD, a nonsignificant increase was seen in those with incident JSN (1.3%), and a nonsignificant reduction was seen in those whose JSN progressed (-2.7%). One hundred forty-five women sustained peripheral fractures, mainly in the distal forearm (27.6%) and vertebrae (28.3%). Women with a peripheral fracture had a reduced risk of subsequently developing incident knee OA (odds ratio [OR] 0.30, 95% confidence interval [95% CI] 0.11-0.84). Although numbers were smaller, nonsignificant reductions in rates of incident OA were seen for those with distal forearm (OR 0.40, 95% CI 0.11-1.49) and vertebral (OR 0.20, 95% CI 0.07-1.61) fractures.

CONCLUSION

These results confirm that for women who develop incident knee OA, defined by osteophytes, BMD is higher and of a magnitude similar to that shown in cross-sectional studies. Low BMD at the hip appears weakly related to progression. Women with previous fractures have less chance of developing OA, independent of BMD status. Although the mechanism for this action is unclear, these results suggest a possible common role of bone turnover and repair in the early manifestations of OA.

Altered bone mineral metabolism in patients with osteoarthritis

OBJECTIVE

Investigation of the relationship between osteoarthritis (OA) and mineral density, and determination of any alteration in bone mineral, metabolism as assessed by biochemical markers of bone resorption and formation.

METHODS

Forty females and 20 males were included in the study. Spinal OA as well as knee OA were defined from radiographs and graded according to Lane et al.'s and Spector et al.'s scoring systems. Bone mineral density (BMD) of the lumbar spine was measured by osteo CT. Bone turnover rates were estimated by measuring biochemical markers of bone resorption (urinary deoxypyridinoline) and bone formation (bone-specific alkaline phosphatase). Forty females and 20 males of the same age were studied as a control group.

RESULTS

BMD was greater in women with spinal OA as compared to controls (P < 0.05). Also, males with OA had a non-significantly higher BMD than controls. The bone resorption markers were higher than normal values. However, they were lower than the control group. Similarly, the bone formation markers were lower as compared to the control group.

CONCLUSION

Spinal OA is associated with higher BMD. This protective effect of spinal OA against osteoporosis may be mediated through decreased rate of bone turnover.

Osteoarthritis and risk of falls, rates of bone loss, and osteoporotic fractures. Study of Osteoporotic Fractures Research Group

OBJECTIVE

To examine the association between osteoarthritis (OA), as defined by radiographic evidence and self report, and osteoporotic fractures, falls, and bone loss in a cohort of elderly white women.

METHODS

A cohort of 5,552 elderly women from the Study of Osteoporotic Fractures was followed up prospectively for a mean of 7.4 years. Self-reported, physician-diagnosed OA was recorded at interview, and radiologic OA of the hip and hand were defined from pelvis and hand radiographs obtained at baseline by validated techniques. Prevalent and incident vertebral fractures were detected by vertebral morphometry, and data on incident fractures and falls were collected by postcard surveys; fractures were confirmed by radiography. Bone mineral density (BMD) was measured on 2 occasions at the hip, lumbar spine, and calcaneus, and rates of bone loss were calculated.

RESULTS

Women with radiographic hip OA had a reduced risk of recurrent falls in the first year (relative risk [RR] 0.7, 95% confidence interval [95% CI] 0.5-0.95). However, those with self-reported OA had an increased risk of falls (RR 1.4, 95% CI 1.2-1.5). Radiographic hip OA was associated with reduced bone loss in the femoral neck compared with controls (mean +/- SD -0.29+/-0.09%/year versus -0.51+/-0.03%/year; P = 0.018). However, radiographic hip OA showed nonsignificant trends toward increased bone loss at the calcaneus and lumbar spine. There was no significant association between self-reported OA or radiographic hand OA with bone loss. No definition of OA was associated with incident nonvertebral fracture, hip fracture, or vertebral fracture.

CONCLUSION

Despite having increased BMD compared with controls, subjects with OA did not have a significantly reduced risk of osteoporotic fracture, although there was a trend toward a reduced risk of femoral neck fractures in subjects with severe radiographic OA. The failure of the observed increase in BMD to translate into a reduced fracture risk may be due, in part, to the number and type of falls sustained by subjects with OA. Patients with OA should not be considered to be at a lower risk of fracture than the general population. Physicians should be aware that a high BMD in patients with OA may be falsely reassuring.

Abnormal cancellous bone collagen metabolism in osteoarthritis

Biochemical investigations into the pathogenesis of osteoarthritis have, for the last two decades, concentrated on the mechanisms involved in the destruction of the articular cartilage. Although bone changes are known to occur, the biochemistry of the collagenous matrix within osteoarthritic bone has received scant attention. We report that bone collagen metabolism is increased within osteoarthritic femoral heads, with the greatest changes occurring within the subchondral zone. Collagen synthesis and its potential to mineralize were determined by the carboxy-terminal propeptide content and alkaline phosphatase activity, respectively. These data supported elevated new matrix formation. Our finding of a three- to fourfold increase in TGF-beta in osteoarthritic bone indicates that this might represent a stimulus for the increased collagen synthesis observed. Of additional significance is the hypomineralization of deposited collagen in the subchondral zone of osteoarthritic femoral heads, supporting a greater proportion of osteoid in the diseased tissue. The cross-linking of collagen was similar to that observed for controls. In addition, the degradative potential of osteoarthritic bone was considerably higher as demonstrated by increased matrix metalloproteinase 2 activity, and again the greater activity was associated with the subchondral bone tissue. The polarization exhibited in the metabolism of bone collagen from osteoarthritic hips might exacerbate the processes involved in joint deterioration by altering joint morphology. This in turn may alter the distribution of mechanical forces to the various tissues, to which bone is a sensitive responder. Bone collagen metabolism is clearly an important factor in the pathogenesis of osteoarthritis and certainly warrants further biochemical study.

What is the relationship between osteoarthritis and osteoporosis?

Several epidemiological studies have shown a lower incidence and prevalence of hip fractures in people with osteoarthritis (OA) and vice versa which has led to numerous studies examining the association between OA and osteoporosis more generally. There is felt to be an inverse relationship between these two diseases and the evidence for and against this association is discussed. The evidence for an association with osteoporosis is stronger for large joint OA than hand OA or primary generalized OA. A number of possible mechanisms for this association are discussed such as genetic factors, common risk factors, role of subchondral bone in cartilage damage and growth factors. The incidence and prevalence of one disease in the presence of the other is discussed. Despite the inverse relationship seen in some studies, there is currently no evidence that treatment of one disease can have a detrimental effect on the other.

Decrease of bone formation in adult women with fragility fractures

OBJECTIVES

To compare bone mineral density (BMD) and some markers of bone metabolism in women with fragility fractures and in normal age-matched subjects.

METHODS

A 100 women with at least one vertebral deformity > 25%, and 219 age-, BMI- and parity-matched healthy women, were recruited for the study. In all the patients fractures were symptomatic and occurred at least 1 year before densitometric measurement. Forearm bone mineral density (BMD) as well as biochemical assessment of some markers of bone turnover were measured in all the subjects.

RESULTS

BMD was significantly lower in the fracture than in the control group (0.326 +/- 0.073 vs. 0.379 +/- 0.079; P < 0.001). Fractured women showed alkaline phosphatase (ALP) and osteocalcin (OC) serum levels significantly lower than controls, while no differences were found in fasting urinary calcium and hydroxyproline excretion. Women without fractures showed a significant correlation between ALP and both age and years since menopause (YSM). Such a correlation is lacking in the fracture group.

CONCLUSIONS

Women with vertebral deformities likely due to a fracture had a forearm BMD and markers of bone formation lower than normal. Whether low bone density is due to a low peak of bone mass or to an increased postmenopausal bone loss sustained by an uncoupling between the two bone remodelling processes is still unclear.