The association of obesity with joint pain and osteoarthritis in the HANES data

Osteoarthritis

The clinical appearance and radiological pattern of osteoarthritis have been identified in the skeletons of dinosaurs some 50-70 million years old, and in Egyptian mummies, and in ancient skeletons in England. Osteoarthritis patterns of joint involvement, often referred to as primary osteoarthritis, can be seen in the hands, spinal facet joints, hips, knees and feet, but can also be termed secondary osteoarthritis when seen in any joint that has had trauma, sepsis, surgery or metabolic insult. The prevalence of osteoarthritis increases with age. The histology and pathophysiology both demonstrate an inflammatory process. While there have been studies of genetic predisposition, the basic cause of primary osteoarthritis has not been determined.

Obesity, Metabolic Syndrome, and Osteoarthritis-An Updated Review

PURPOSE OF REVIEW

Metabolic syndrome (MetS), also called the 'deadly quartet' comprising obesity, diabetes, dyslipidemia, and hypertension, has been ascertained to have a causal role in the pathogenesis of osteoarthritis (OA). This review is aimed at discussing the current knowledge on the contribution of metabolic syndrome and its various components to OA pathogenesis and progression.

RECENT FINDINGS

Lately, an increased association identified between the various components of metabolic syndrome (obesity, diabetes, dyslipidemia, and hypertension) with OA has led to the identification of the 'metabolic phenotype' of OA. These metabolic perturbations alongside low-grade systemic inflammation have been identified to inflict detrimental effects upon multiple tissues of the joint including cartilage, bone, and synovium leading to complete joint failure in OA. Recent epidemiological and clinical findings affirm that adipokines significantly contribute to inflammation, tissue degradation, and OA pathogenesis mediated through multiple signaling pathways. OA is no longer perceived as just a 'wear and tear' disease and the involvement of the metabolic components in OA pathogenesis adds up to the complexity of the disease. Given the global surge in obesity and its allied metabolic perturbations, this review aims to throw light on the current knowledge on the pathophysiology of MetS-associated OA and the need to address MetS in the context of metabolic OA management. Better regulation of the constituent factors of MetS could be profitable in preventing MetS-associated OA. The identification of key roles for several metabolic regulators in OA pathogenesis has also opened up newer avenues in the recognition and development of novel therapeutic agents.

The Association of Metabolic Syndrome and Obesity With Clinical Hip Osteoarthritis in the Study of Osteoporotic Fractures and the Osteoporotic Fractures in Men Study Cohorts

OBJECTIVE

Metabolic dysregulation frequently co-occurs with obesity, which has been shown to be a risk factor for lower extremity osteoarthritis (OA). We evaluated the association between metabolic syndrome (MetS), alone and in combination with obesity, and hip OA.

METHODS

In two parallel cross-sectional analyses, we studied 403 women from the Study of Osteoporotic Fractures (SOF) and 2354 men from the Osteoporotic Fractures in Men (MrOS) study. We used multivariable logistic regression to evaluate associations of obesity (body mass index ≥30 kg/m2 ) and/or MetS (three of five National Cholesterol Education Program Adult Treatment Panel III criteria) with clinical hip OA, defined as a modified Croft score of 2 or more or total hip replacement, and pain or limited range of motion. Our analysis adjusted for demographics.

RESULTS

Approximately 3.5% of SOF women and 5.4% of MrOS men had clinical hip OA. Among women, obesity was not associated with hip OA, yet those with MetS had a 365% higher odds of hip OA (95% CI: 1.37-15.83). Among men, those who had obesity had a 115% higher odds of hip OA (95% CI: 1.39-3.32), yet MetS was not associated with hip OA. There was no interaction between MetS, obesity, and hip OA in either women or men.

CONCLUSION

In women, but not in men, MetS was associated with hip OA. In men, but not in women, obesity was associated with hip OA. These findings suggest that mechanical effects of obesity may predominate in the pathogenesis of hip OA in men, whereas metabolic effects predominate in women.

Physiological Changes and Pathological Pain Associated with Sedentary Lifestyle-Induced Body Systems Fat Accumulation and Their Modulation by Physical Exercise

A sedentary lifestyle is associated with overweight/obesity, which involves excessive fat body accumulation, triggering structural and functional changes in tissues, organs, and body systems. Research shows that this fat accumulation is responsible for several comorbidities, including cardiovascular, gastrointestinal, and metabolic dysfunctions, as well as pathological pain behaviors. These health concerns are related to the crosstalk between adipose tissue and body systems, leading to pathophysiological changes to the latter. To deal with these health issues, it has been suggested that physical exercise may reverse part of these obesity-related pathologies by modulating the cross talk between the adipose tissue and body systems. In this context, this review was carried out to provide knowledge about (i) the structural and functional changes in tissues, organs, and body systems from accumulation of fat in obesity, emphasizing the crosstalk between fat and body tissues; (ii) the crosstalk between fat and body tissues triggering pain; and (iii) the effects of physical exercise on body tissues and organs in obese and non-obese subjects, and their impact on pathological pain. This information may help one to better understand this crosstalk and the factors involved, and it could be useful in designing more specific training interventions (according to the nature of the comorbidity).

Assessment of the Degree of Osteoarthritis in Aging Male and Female Femoral Condyles: A Cadaveric Study

OBJECTIVE

Determine if femoral chondral cartilage degeneration on cadaveric knee joints exacerbate differently with aging between the sexes.

METHODS

A total of 85 cadaveric femurs were assessed for macroscopic femoral condyle pathology using a scale for gross signs of osteoarthritis. Raters scored specimens and raters' scores were averaged to provide each specimen a Disease Severity Score (DSS).

RESULTS

The DSS for the 80+-year-old population was greater than the DSS of the 70- to 79-year-old population (*P < 0.05) and the <70-year-old population (**P < 0.01). Specimens that scored a DSS of 2 and higher were assessed for their specific site of most severe degeneration. The most severe degeneration on the articular cartilage was most regularly on the patellar fossa. The second most degenerated region varied by age and biomechanical alterations. There were no significant changes in DSS between the sexes within the age groups.

CONCLUSIONS

No difference was shown between the sexes in the severity or location of degeneration indicating that men and women are likely affected by the same biomechanical changes that spur on osteoarthritis in their eighth decade of life (70s) and later. Lateral femoral degeneration predominates in younger populations. When patients approach their 70s, medial degeneration begins to predominate likely based on an increase in shearing at the knee joint.

AAAPT Diagnostic Criteria for Acute Knee Arthroplasty Pain

OBJECTIVE

The relationship between preexisting osteoarthritic pain and subsequent post-total knee arthroplasty (TKA) pain is not well defined. This knowledge gap makes diagnosis of post-TKA pain and development of management plans difficult and may impair future investigations on personalized care. Therefore, a set of diagnostic criteria for identification of acute post-TKA pain would inform standardized management and facilitate future research.

METHODS

The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership with the US Food and Drug Administration (FDA), the American Pain Society (APS), and the American Academy of Pain Medicine (AAPM) formed the ACTTION-APS-AAPM Pain Taxonomy (AAAPT) initiative to address this goal. A multidisciplinary work group of pain experts was invited to conceive diagnostic criteria and dimensions of acute post-TKA pain.

RESULTS

The working group used contemporary literature combined with expert opinion to generate a five-dimensional taxonomical structure based upon the AAAPT framework (i.e., core diagnostic criteria, common features, modulating factors, impact/functional consequences, and putative mechanisms) that characterizes acute post-TKA pain.

CONCLUSIONS

The diagnostic criteria created are proposed to define the nature of acute pain observed in patients following TKA.

The Effect of Body Mass Index on Functional Outcome of Patients With Knee Replacement

Objective

To investigate the effects of body mass index (BMI) on the rehabilitation process in patients with a recent knee replacement.

Design

This retrospective cohort study included all patients admitted to a rehabilitation hospital, with a recent diagnosis of knee replacement and available hospital admission data including height and weight, between 2014 and 2017.

Setting

Rehabilitation hospital.

Participants

Study participants included patients who had undergone knee replacement surgery (N=742), with available BMI data.

Interventions

None.

Main Outcome Measures

FIM scores, including FIM change per day (FIM efficiency) by BMI category.

Results

The chart review identified 742 patients who had undergone knee replacement surgery, with available BMI data. The identified patients ranged in age from 58 to 85 years, with a mean age of 70 years. Of the patients included in the study, 24 were male, 49 were female, 73 were within the normal weight class, 180 in the overweight class, 189 in the obese class I, 143 in the obese class II, and 157 patients were classified as obese class III. The mean FIM efficiency was highest in the obese class II category (3.96). In a multivariate analysis after controlling for age, obese classes II and III had significantly better FIM efficiency.

Conclusion

This study did not demonstrate that obesity adversely affects the rate of recovery during hospitalization after knee replacement surgery.

Perioperative impact of sleep apnea in a high-volume specialty practice with a strong focus on regional anesthesia: a database analysis

Background and objectives

Obstructive sleep apnea (OSA) is a risk factor for adverse postoperative outcome and perioperative professional societies recommend the use of regional anesthesia to minimize perioperative detriment. We studied the impact of OSA on postoperative complications in a high-volume orthopedic surgery practice, with a strong focus on regional anesthesia.

Methods

After Institutional Review Board approval, 41 766 cases of primary total hip and knee arthroplasties (THAs/TKAs) from 2005 to 2014 were extracted from institutional data of the Hospital for Special Surgery (approximately 5000 THAs and 5000 TKAs annually, of which around 90% under neuraxial anesthesia).

The main effect was OSA (identified by the International Classification of Diseases, ninth revision codes); outcomes of interest were cardiac, pulmonary, gastrointestinal, renal/genitourinary, thromboembolic complications, delirium, and prolonged length of stay (LOS). Multivariable logistic regression models provided ORs, corresponding 95% CIs, and p values.

Results

Overall, OSA was seen in 6.3% (n=1332) of patients with THA and 9.1% (n=1896) of patients with TKA. After adjustment for relevant covariates, OSA was significantly associated with 87% (OR 1.87, 95% CI 1.51 to 2.30), 52% (OR 1.52, 95% CI 1.13 to 2.04), and 44% (OR 1.44,95% CI 1.31 to 1.57) increased odds for pulmonary gastrointestinal complications, and prolonged LOS, respectively. The odds for other outcomes remained unaltered by OSA diagnosis.

Conclusion

We showed that, even in a setting with almost universal regional anesthesia use, OSA was associated with increased odds for prolonged LOS, and pulmonary and gastrointestinal complications. This puts forward the question of how effective regional anesthesia is in mitigating postoperative complications in patients with OSA.

The relation between obesity and depressed mood in a multi-ethnic population. The HELIUS study

PURPOSE

To examine the association between obesity and depressed mood in a large multi-ethnic population and check for consistency in this association across six ethnic groups.

METHODS

Data of 21,030 persons (18-70 years) were sourced from the HELIUS study. Cross-sectional relationships between obesity measures [body mass index (kg/m²) and waist circumference (cm)] and depressed mood (PHQ-9 score ≥ 10) were analysed. Consistency of associations was investigated across ethnic groups by interaction terms (ethnicity*obesity measures) in basic (age, sex, education) and fully (health behaviours and somatic health) adjusted models.

RESULTS

Obesity was prevalent in all ethnic groups, but varied substantially. After sociodemographic adjustment, obesity measures were associated with increased odds of depressed mood but this was inconsistent across ethnic groups. Obesity (BMI ≥ 30 or highest waist circumference quartile) was strongly and significantly associated with depressed mood in the Dutch [Odds Ratio (OR) = 1.72; 95% Confidence intervals (CI) 1.24-2.40, and OR = 1.86; 95% CI 1.38-2.50], respectively, and African Surinamese (OR = 1.60; 95% CI 1.29-1.98 and OR = 1.59; 95% CI 1.27-2.00, respectively) but had a weaker, non-significant association in other ethnic groups (South-Asian Surinamese, Ghanaian, Moroccan, Turkish groups). Adjustment for health behaviours and somatic health had limited effect on this pattern.

CONCLUSION

Obesity was associated with a higher risk of depressed mood. However, ethnic differences were found: the obesity-depressed mood association was strong in the Dutch and African Surinamese populations, but not in other ethnic groups. Future studies should explore whether differential normative values or pathophysiology across ethnic groups explain why the obesity-depression association is inconsistent across ethnic groups.

No influence of obesity on survival of cementless, posterior-stabilised, rotating-platform implants

INTRODUCTION

This study compares survival and outcomes in four total knee arthroplasty (TKA) populations defined by baseline body mass index (BMI). We hypothesised that there would be no difference in survival between the groups.

MATERIALS AND METHODS

Using an initial cohort of 1059 TKAs, BMI was systematically measured prior to surgery. A retrospective study was conducted and patients were accordingly allocated to four groups: normal or underweight (BMI < 25; n = 111), overweight (25 ≤ BMI < 30; n = 417), moderately obese (30 ≤ BMI < 35; n = 330) and severely or morbidly obese (BMI ≥ 35; n = 201). The pre- and postoperative clinical and radiographical profiles of the four groups were compared, along with any postoperative complications and the survival of each group. The minimum follow-up was 24 months. All implants had an ultra-congruent cementless posterior-stabilised rotating-platform design (Amplitude^®). The primary endpoint was implant survival using Kaplan-Meier analysis. Statistical analysis was conducted using Chi-squared and Kruskal-Wallis H tests to compare the data with p < 0.05.

RESULTS

A total of 94 knees from normal weight or underweight individuals were analysed, 346 from overweight, 281 from moderately obese and 159 from severely or morbidly obese. All knees had been operated on between 2002 and 2011 with an average follow-up of 61.7 (12-146) months. A greater degree of obesity was significantly correlated with young age at intervention (p < 0.001), as well as with a low average preoperative maximum flexion angle (p < 0.001) and KSS (p < 0.001). Postoperatively, there were no significant differences between the groups in terms of patient satisfaction (p = 0.9) or mechanical axial deviation evaluated with whole-leg standing radiography (mFTA, p = 0.3; mFA, p = 0.1; mTA, p = 0.3). The greater the degree of obesity, the lower the average postoperative maximum flexion angle (p < 0.001), KSS knee score (p < 0.001) and function score (p = 0.005). There was no significant difference between the groups in terms of total rate of postoperative complications (p = 0.9) or implant revision (p = 0.9), or in terms of 10-year implant survival (p = 0.4).

CONCLUSIONS

Obesity does not affect mid-term implant survival, irrespective of BMI, but has a negative influence on functional outcomes and potential risk of postoperative complications.

Mechanisms of weight loss and improved metabolism following bariatric surgery

Bariatric surgery is increasingly recognized as one of the most effective interventions to help patients achieve significant and sustained weight loss, as well as improved metabolic and overall health. Unfortunately, the cellular and physiological mechanisms by which bariatric surgery achieves weight loss have not been fully elucidated, yet are critical to understanding the central role of the intestinal tract in whole-body metabolism and to developing novel strategies for the treatment of obesity. In this review, we provide an overview of potential mechanisms contributing to weight loss, including effects on regulation of energy balance and both central and peripheral nervous system regulation of appetite and metabolism. Moreover, we highlight the importance of the gastrointestinal tract, including alterations in bile acid physiology, secretion of intestinally derived hormones, and the microbiome, as a potent mediator of improved metabolism in postbariatric patients.

Self-reported knee pain and disability among healthy individuals: reference data and factors associated with the Knee injury and Osteoarthritis Outcome Score (KOOS) and KOOS-Child

OBJECTIVE

To develop normative reference data for the Knee injury and Osteoarthritis Outcome Score (KOOS) and KOOS-Child, as well as investigate socio-demographic, psychological and physical factors associated with knee pain and disability among healthy adults.

METHOD

The KOOS or KOOS-Child (each containing five subscales) was administered to participants aged 8-101 years within the 1000 Norms Project, an observational study of 1000 self-reported healthy individuals. Self-efficacy, physical activity, body mass index (BMI), lower limb alignment, knee frontal plane projection angle (FPPA), knee range of motion (ROM), knee and hip strength, six-minute walk, 30-second chair stand and timed up and down stairs tests were collected. KOOS data were dichotomised using established cut-off scores and logistic regression analyses were conducted for each subscale.

RESULTS

Socio-demographic characteristics were similar to the Australian population. Normative reference data were generated for children (8-17 years) and adults (18-101 years). Female adults were up to twice as likely to report knee pain, symptoms and sport/recreation (Sport/Rec) limitations compared to males (P < .05). Older age, lower self-efficacy, greater BMI, varus lower limb alignment, lower knee flexion ROM and lower hip external rotation (ER) strength were independently associated with knee pain and disability among adults.

CONCLUSIONS

Age- and gender-stratified reference data for the KOOS and KOOS-Child have been developed to guide interpretation of results in practice and research for individuals with knee disorders. Psychological and physical factors are linked with self-reported knee pain/disability among adults, and longitudinal studies to investigate causation are required.

Clinical and Functional Results of 119 Patients With Knee Dislocations

OBJECTIVES

To describe clinical results and functional outcomes of knee dislocations treated with a consistent strategy within our institution.

DESIGN

Retrospective case series.

SETTING

Level 1 trauma center.

PATIENTS

One hundred nineteen patients were treated at one institution between 2000 and 2014 for knee dislocation.

MAIN OUTCOME MEASUREMENTS

Knee range of motion, functional instability, and complications were recorded. Musculoskeletal Function Assessment (MFA) and Lysholm scores were obtained after minimum of 1 year.

RESULTS

Sixty-three early complications were noted in 36 patients (32%), with an overall amputation rate of 9.2% (8 early and 3 late amputations). Of the patients who retained their limb, 4.5% reported instability. Open knee dislocations were associated with amputation (26% vs. 1.3%, P < 0.001). Popliteal arterial injuries were associated with more amputation (31% vs. 3.2%, P = 0 < 0.001), infection (37% vs. 8%, P = 0.002), and deep venous thrombosis (32% vs. 8.8%, P = 0.014). Patients with wound infection were more likely to develop heterotopic ossification (36% vs. 9.4%, P = 0.017) and less knee motion (77.5 vs. 117 degrees P = 0.049). Knee motion improved over time for all patients with a mean arc of 86 degrees at 3 months, 109 degrees at 6 months, and 115 degrees at 12 months. An Injury Severity Score of ≥20 was associated with less knee motion (97 vs. 121 degrees P = 0.029). Mean Lysholm score was 86.7, and mean MFA score was 35.7 after mean follow-up of 90 months and 82 months, respectively.

CONCLUSIONS

Few patients (4.5%) experienced functional instability. However, early complications occurred frequently (32%) as expected, particularly in patients with open injuries and/or arterial injury. Limitations in knee motion were associated with high Injury Severity Score, infection, and heterotopic ossification. Mean knee scores were good, consistent with reasonable knee function, although MFA scores suggest a lower level of generalized function.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Hip Osteoarthritis: Etiopathogenesis and Implications for Management

Highly prevalent among the elderly, hip osteoarthritis (OA) carries a heavy burden of disease. Guidelines for the management of hip OA are often extrapolated from knee OA research, despite clear differences in the etiopathogenesis and response to treatments of OA at these sites. We propose that hip OA requires specific attention separate from other OA phenotypes. Our understanding of the etiopathogenesis of hip OA has seen significant advance over the last 15 years, since Ganz and colleagues proposed femoroacetabular impingement (FAI) as an important etiological factor. This narrative review summarizes the current understanding of the etiopathogenesis of hip OA and identifies areas requiring further research. Therapeutic approaches for hip OA are considered in light of the condition’s etiopathogenesis. The evidence for currently adopted management strategies is considered, especially those approaches that may have disease-modifying potential. We propose that shifting the focus of hip OA research and public health intervention to primary prevention and early detection may greatly improve the current management paradigm.

Relationship between frequent knee pain, obesity, and gait speed in older adults: data from the Osteoarthritis Initiative

Background

Knee pain (KP) causes gait difficulties in older adults and is associated with slow gait speed (GS). Obesity has negative effects on health. GS is an important indicator of health, well-being, and mean life span in older adults and is a strong predictor of future disability and mortality. The relationship between frequent KP, obesity, and GS in older adults remains unclear. Therefore, the present study aimed at examining the relationship between baseline frequent KP and obesity status on GS over time. We hypothesized that frequent KP, obesity, or both would be associated with decreased GS over time.

Methods

The data from the Osteoarthritis Initiative were used for this 6-year longitudinal cohort study. We studied 3,118 adults aged between 45 years and 79 years. We grouped the participants into the following four categories according to KP frequency and obesity status at baseline: 1) no KP and nonobese, 2) frequent KP and nonobese, 3) no KP and obese, and 4) frequent KP and obese. GS measurements were based on a 20 m walking test timed using a stopwatch; testing was performed at baseline and over a 6-year follow-up period. Walk pace (m/sec) was calculated as the average pace over two trials conducted at clinic visits. General linear mixed models were used to examine the relationships between frequent KP, obesity, and GS.

Results

After adjusting for all covariates, at baseline, all the nonobese group with frequent KP (β=−0.06, 95% confidence interval [CI]: −0.07 to −0.04), the obese group with no KP (β=−0.07, 95% CI: −0.1 to −0.04), and the obese group with frequent KP (β=−0.08, 95% CI: −0.1 to −0.05) exhibited decreased GS compared with the nonobese and no KP group. However, the associations between frequent KP, obesity, and GS over time were not statistically significant.

Conclusion

Frequent KP alone, obesity alone, and the combination of frequent KP and obesity were all associated with decreased GS in older adults. These associations did not change in any of the groups longitudinally; as such, the slopes corresponding to the data remained unchanged.

Evaluation of acute and chronic MRI features of sacroiliitis in asymptomatic primary hyperparathyroid patients

Asymptomatic primary hyperparathyroidism (PHPT) is characterized with autonomous overproduction of parathyroid hormone without signs or symptoms associated with hyperparathyroidism. Before symptoms become obvious, PHPT may affect structures like sacroiliac joints, which consist of bone. So, in the asymptomatic PHPT patients, structural and inflammatory changes in sacroiliac joints may lead to confusion during diagnosis workup of axial spondyloarthropathy. In this study, we evaluated active and chronic sacroiliac magnetic resonance imaging (MRI) changes relevant to sacroiliitis in the patients with asymptomatic PHPT and interpreted bone marrow edema within the scope of Assessment of SpondyloArthritis International Society-Outcome Measures in Rheumatology Clinical Trials (ASAS-OMERACT) criteria. Forty-nine patients with asymptomatic PHPT, 26 patients with newly diagnosed axial spondyloarthropathy (SpA), and 37 healthy controls were enrolled. All subjects were evaluated by sacroiliac MRI for four active (bone marrow edema, enthesitis, capsulitis, and synovitis) and four chronic (subchondral sclerosis, subchondral/periarticular erosions, periarticular fat deposition, and bony bridges/ankylosis) lesions relevant to sacroiliitis. Bone marrow edema compatible with ASAS-OMERACT active sacroiliitis criteria in sacroiliac MRI was fulfilled by 16.3 % (8/49) of the asymptomatic PHPT patients which was similar with controls but statistically lower than axial SpA. Moreover, asymptomatic PHPT patients and controls were similar for other chronic or active MRI findings. Also, we detected lower frequency of all other MRI findings, except enthesis, in asymptomatic PHPT patients according to axial SpA. Acute inflammatory including bone marrow edema fulfilling ASAS-OMERACT active sacroiliitis criteria and chronic structural sacroiliac lesions relevant to sacroiliitis in MRI were detected in asymptomatic PHPT similar frequency with controls but as expected, lower than axial SpA. But, these findings could not be attributed to excessive secretion of parathyroid hormone.

[Knee dysfunction in the general population and associated factors]

BACKGROUND

Knee joint dysfunction is present in 80% of people over 50 years of age, and in women there is a 1.5 times higher risk compared to men. Another important risk factor is obesity, which leads to a 3 times increase in the risk of suffering functional limitations in the joint. The aim of this study was to determine knee joint dysfunction and the associated factors.

MATERIAL AND METHODS

An analytical and descriptive study was conducted on 218 individuals older than 50 years of age in a primary care centre. A physical examination was performed on each patient, and the Western Ontario and McMaster Universities Osteoarthritis Index questionnaire was applied to them all. Logistic regression analysis was used to determine the association between age, gender, body mass index, and knee function. ANOVA was used to compare the means of the Western Ontario and McMaster Universities Osteoarthritis Index scores and body mass index measurements. A p<0.05 was considered statistically significant.

RESULTS

The mean age was 64.27 years (SD 10.43). An OR of 4.50 was obtained for having a disability in people over 65 years of age, 2.90 in obese people, and 2.02 in women. The mean scores in the 3 domains of Western Ontario and McMaster Universities Osteoarthritis Index were higher as the body mass index increased.

CONCLUSIONS

Women have greater disability than men, becoming more evident in older ages, and other risk of joint dysfunction increases up 3 times in obese patients.

Stretchable Heater Using Ligand-Exchanged Silver Nanowire Nanocomposite for Wearable Articular Thermotherapy

Thermal therapy is one of the most popular physiotherapies and it is particularly useful for treating joint injuries. Conventional devices adapted for thermal therapy including heat packs and wraps have often caused discomfort to their wearers because of their rigidity and heavy weight. In our study, we developed a soft, thin, and stretchable heater by using a nanocomposite of silver nanowires and a thermoplastic elastomer. A ligand exchange reaction enabled the formation of a highly conductive and homogeneous nanocomposite. By patterning the nanocomposite with serpentine-mesh structures, conformal lamination of devices on curvilinear joints and effective heat transfer even during motion were achieved. The combination of homogeneous conductive elastomer, stretchable design, and a custom-designed electronic band created a novel wearable system for long-term, continuous articular thermotherapy.

The Link between Musculoskeletal Pain, Lifestyle Behaviors, Exercise Self-Efficacy, and Quality of Life in Overweight and Obese Individuals

Objective

To determine the extent musculoskeletal (MS) pain in the low back and knee (weight-bearing (WB) joints), shoulder and wrist (non-weight bearing joints), and exercise self-efficacy mediates associations between overweight and obesity levels based on BMI (4 levels: overweight, obese class I, II, or III), physical function, emotional role, social interference, and physical activity (PA) levels.

Design

Cross-sectional study.

Setting

Four long-term nursing home facilities in the Northeast U.S.

Participants

99 overweight or obese (BMI > 25) nursing home employees.

Interventions

Self-reported survey administered to employees who met inclusion and exclusion criteria.

Main Outcome Measure(s)

General health status, physical function, emotional role, Exercise Self-Efficacy Scale (ESE), physical activity (PA), and frequency of pain at each joint.

Results

Reported pain frequency were 66.3%, 54.4%, 42.2%, and 24.1% for lower back, knee, shoulder, and wrist, respectively. Higher obesity levels were associated with lower physical function (r=−0.109, p=0.284). PA decreased with higher obesity levels (r=−0.248, p<0.05), particularly in moderate PA (r=−0.293, p<0.05). Obesity was associated with a lower ESE (r=−0.239, p<0.05). Wrist pain significantly mediated the effect of obesity on moderate physical function, emotional role, and ESE. ESE was a significant mediator between obesity and moderate and vigorous PA.

Conclusions

Overweight and obese nursing home employees are at higher risk for developing musculoskeletal disorders due to high demand, low control jobs, and the associated biomedical compromises while working. To increase the effectiveness of weight loss interventions for this population, the mediating effects of MS pain with higher levels of obesity should be considered.

Changing incidence of orthopedic surgery in rheumatic disease: contributing factors

Rheumatic diseases are multisystem conditions that predominantly affect the musculoskeletal system, leading to soft tissue and articular damage. Historically, medical therapy was able to slow, but not prevent, erosion and joint destruction, resulting in the frequent need for orthopedic procedures to maintain function and minimize pain. However, the widespread use of disease-modifying anti-rheumatic drugs (DMARDs) and biologic therapy over the last twenty years has resulted in a dramatic decrease in the incidence of musculoskeletal damage and impairment among these patients. This review will discuss changing patterns of orthopedic surgery among patients with rheumatic diseases, focusing on rheumatoid arthritis and systemic lupus erythematosus.

Body mass index, pain and function in individuals with knee osteoarthritis

BACKGROUND

Obesity is a risk factor for progression of knee osteoarthritis (OA), and high body mass index (BMI) may interfere with treatment effectiveness on pain and function in individuals with knee OA. This study investigated the effects of BMI on pain and function during a four-week exercise programme in patients with knee OA.

MATERIALS AND METHODS

Forty-six (31 women and 15 men) participants with knee OA of different BMI categories (15 normal weight participants, 13 over weight participants and 18 obese participants), received standardised exercise therapy programme twice a week for 4 weeks. Outcome included a 10-point pain rating scale for pain-intensity and the western Ontario and McMaster university osteoarthritis index (WOMAC) for physical function.

RESULTS

Two-way repeated measure analysis of variance (ANOVA) on pain assessment score revealed a significant effect of time (F = 1049.401, P < 0.001) and group (F = 9.393, P < 0.001) on pain. Similar significant effect of time (F = 595.744, P < 0.001) and group (F = 5.431, P = 0.008) was obtained for WOMAC score on function. Post hoc analysis revealed significant difference between the normal weight and overweight group (t = 2.472, P = 0.016) and between normal weight and obese group (t = 3.893, P = 0.005) on pain outcome at the 4(th) week post treatment. No significant difference was found at 4(th) week post treatment on WOMAC scores (F = 2.010, P = 0.146).

CONCLUSION

Exercise improved pain and function scores in OA patients across the BMI groups. Overweight independent of obesity may interfere with effectiveness of pain control during the symptomatic treatment of knee OA patients.

Utilisation of primary total knee joint replacements across socioeconomic status in the Barwon Statistical Division, Australia, 2006-2007: a cross-sectional study

OBJECTIVES

There are few Australian data that examine the association between total knee joint replacement (TKR) utilisation and socioeconomic status (SES). This study examined TKR surgeries with a diagnosis of osteoarthritis (OA) performed for residents of Barwon Statistical Division (BSD) for 2006-2007.

DESIGN

Cross-sectional.

SETTING

BSD, South-eastern Victoria, Australia

PARTICIPANTS

All patients who underwent a TKR for OA, 2006-2007, and whose residential postcode was identified as within the BSD of Australia, and for whom SES data were available, were eligible for inclusion.

PRIMARY OUTCOME MEASURE

Primary TKR data ascertained from the Australian Orthopaedic Association National Joint Replacement Registry. Residential addresses were matched with the Australian Bureau of Statistics census data, and the Index of Relative Socioeconomic Disadvantage was used to determine SES, categorised into quintiles whereby quintile 1 indicated the most disadvantaged and quintile 5 the least disadvantaged. Age-specific and sex-specific rates of TKR utilisation per 1000 person-years were reported for 10-year age bands.

RESULTS

Females accounted for 62.7% of the 691 primary TKR surgeries performed during 2006-2007. The greatest utilisation rates of TKR in males was 7.6 observed in those aged >79 years, and in 10.2 in females observed in those aged 70-79 years. An increase in TKR was observed for males in SES quintile four compared to quintile 1 in which the lowest utilisation which was observed (p=0.04). No differences were observed in females across SES quintiles.

CONCLUSIONS

Further investigation is warranted on a larger scale to examine the role that SES may play in TKR utilisation, and to determine whether any social disparities in TKR utilisation reflect health system biases or geographic differences.

Use of knee magnetic resonance imaging by primary care physicians in patients aged 40 years and older

BACKGROUND

Criteria are needed for primary care providers such that they can evaluate age-related knee pain in a cost-effective manner. This study examined (1) in what percentage of patients are appropriate radiographic views of the knee ordered before magnetic resonance imaging (MRI) for knee pain, (2) specialists' retrospective evaluation for appropriate utilization of MRI in knee pain, and (3) in what manner would the MRIs have altered diagnosis and management of knee disorders.

HYPOTHESIS

Primary care providers underuse appropriate radiographs-especially, flexion weightbearing posteroanterior films-and overuse MRIs when evaluating older patients with knee pain.

STUDY DESIGN

Case control.

METHODS

The authors performed a retrospective analysis of 100 patients older than 40 years with knee MRIs. Patient encounters with primary care physicians were reviewed. Given available information, specialists then formulated a pre- and post-MRI diagnosis and treatment plan and indicated whether the MRI would have altered their treatment.

RESULTS

Only 12 of 100 MRIs would have been ordered by an orthopaedist given the documented data. No MRIs would have been ordered in the 19 patients aged 60 years or older. Among 44 radiographs ordered, only 7 were flexion weightbearing. The most common pre-MRI diagnoses made by primary care providers were joint pain (22%) and meniscus injury (24%); the most common post-MRI diagnoses were osteoarthritis (40%) and degenerative meniscus injury (23%). In contrast, the 2 most common pre- and post-MRI diagnoses by specialists were osteoarthritis (28% and 37%, respectively) and degenerative meniscus injury (23% and 24%, respectively). Also, referrals to specialists increased from 9% pre-MRI to 76% post-MRI.

CONCLUSION

Primary care providers may be overusing knee MRIs and underusing flexion weightbearing posteroanterior radiographs in patients older than 40 years with knee pain.

CLINICAL RELEVANCE

Primary care providers should strongly consider not ordering knee MRI in patients with radiographic evidence of degenerative changes.

COMPARING QUALITY OF LIFE AMONG PEOPLE WITH DIFFERENT PATTERNS AND SEVERITIES OF KNEE OSTEOARTHRITIS

Objective: To identify what extent different patterns and severities of involvement affect quality of life of people suffering knee osteoarthritis.

Methods: This population-based survey involved 288 women and 288 men aged 40 years or older from Songkhla province, southern Thailand. Quality of life was measured using the Medical Outcome Study Short Form Health sutvery (SF-36) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Radiographic investigation included antero-posterior and skyline view of both knees. Osteoarthritis was categorized into 3 patterns; isolated patellofemoral, isolated tibiofemoral and combined with diagnosis based on Kellgren & Lawrence grade 2 or higher.

Results: Quality of life as measured by SF-36 and WOMAC showed poorer score in moderate or severe grade than in mild grade of severity. Isolated patellofemoral and combined patterns demonstrated showed poorer scores on both WOMAC and SF-36 than isolated tibiofemoral pattern. Body mass index, income level and pattern of involvement could independently predict total scores of WOMAC, while age, marital status and pattern of involvement affected total score of SF-36.

Conclusion: Pattern of involvement is a better predictor of quality of life than disease severity in patients with knee osteoarthritis.

Ottawa Panel evidence-based clinical practice guidelines for the management of osteoarthritis in adults who are obese or overweight

BACKGROUND AND PURPOSE

The objective of this review was to construct an updated evidence-based clinical practice guideline on the use of physical activity and diet for the management of osteoarthritis (OA) in adults (>18 years of age) who are obese or overweight (body mass index ≥25 kg/m(2)).

DATA SOURCES

Articles were extracted from the following databases: MEDLINE, EMBASE (Current Contents), SPORTDiscus, SUM, Scopus, CINAHL, AMED, BIOMED, PubMed, ERIC, the Cochrane Controlled Trials, and PEDro.

STUDY SELECTION

The Ottawa Panel and research assistance team strictly applied the inclusion and exclusion criteria from previous Ottawa Panel publications.

DATA EXTRACTION

An a priori literature search was conducted for articles related to obesity and OA of the lower extremities that were published from January 1, 1966, to November 30, 2010. Inclusion criteria and the methods to grade the recommendations were created by the Ottawa Panel.

RECOMMENDATIONS

were graded based on the strength of evidence (A, B, C, C+, D, D+, or D-) as well as experimental design (I for randomized controlled trials and II for nonrandomized studies). In agreement with previous Ottawa Panel methods, Cochrane Collaboration methods were utilized for statistical analysis. Clinical significance was established by an improvement of ≥15% in the experimental group compared with the control group. There were a total of 79 recommendations from 9 articles. From these recommendations, there were 36 positive recommendations: 21 grade A and 15 grade C+. There were no grade B recommendations, and all recommendations were of clinical benefit.

LIMITATIONS

Further research is needed, as more than half of the trials were of low methodological quality.

CONCLUSIONS

This review suggests that physical activity and diet programs are beneficial, specifically for pain relief (9 grade A recommendations) and improved functional status (6 grade A and 7 grade C+ recommendations), for adults with OA who are obese or overweight. The Ottawa Panel was able to demonstrate that when comparing physical activity alone, diet alone, physical activity combined with diet, and control groups, the intervention including physical activity and diet produced the most beneficial results.

Significant J-shaped association between body mass index (BMI) and diabetic foot ulcers

BACKGROUND

Disagreement exists regarding the relationship between body weight and foot ulceration risk among diabetic persons.

METHODS

We used a nested case-control design to estimate the association between body mass index (BMI) and 1-year and 5-year foot ulceration risk. We obtained data on all diabetic patients < 60 years of age who were treated in the US Department of Veterans Affairs healthcare system in 2003. Patient characteristics and co-morbidities were obtained at baseline. For each individual with an incident foot ulcer (case), up to four individuals were randomly selected who matched the case on age, sex, race, marital status, and calendar time.

RESULTS

Crude 1-year and 5-year incidence rates were 1.35 and 6.22% after a mean follow-up of 11.8 ± 1.2 months and 55.5 ± 12.8 months, respectively. Compared with individuals with BMI 25-29.9 kg/m(2) , those with BMI 40-44.9 kg/m(2) and those with BMI ≥ 45 kg/m(2) had 25% [adjusted odds ratio (AOR) = 1.25; 95% confidence interval (CI), 1-1.56] and 83% (AOR = 1.83; 95% CI, 1.44-2.32) higher 1-year risk and 1.4 (AOR = 1.39; 95% CI, 1.26-1.54) and 2.1 (AOR = 2.08; 95% CI, 1.86-2.32) times higher 5-year risk. BMI < 25 kg/m(2) was associated with 30% higher risk at both 1 year (AOR = 1.28; 95% CI, 1.04-1.58) and 5 years (AOR = 1.27; 95% CI, 1.15-1.40).

CONCLUSIONS

Our data suggest a significant J-shaped association between BMI and diabetic foot ulcers.

Does high weight loss in older adults with knee osteoarthritis affect bone-on-bone joint loads and muscle forces during walking?

OBJECTIVE

The aim of this study was to examine the effects of high weight loss on knee joint loads during walking in participants with knee osteoarthritis (OA).

DESIGN

Data were obtained from a subset of participants enrolled in the Arthritis, Diet, and Activity Promotion Trial (ADAPT). Complete baseline and 18-month follow-up data were obtained on 76 sedentary, overweight or obese older adults with radiographic knee OA. Three-dimensional gait analysis was used to calculate knee joint forces and moments. The cohort was divided into high (>5%), low (<5%), and no (0% or gain) weight loss groups.

RESULTS

From baseline body weight, the high weight loss group lost an average of 10.2%, the low weight loss group lost an average of 2.7%, and the no weight loss group gained 1.5%. Adjusted 18-month outcome data revealed lower maximum knee compressive forces with greater weight loss (P=0.05). The difference in compressive forces between the high weight loss and no weight loss groups was due primarily to lower hamstring forces (P=0.04). Quadriceps forces were similar between the groups at 18-month follow-up. There was no difference between the groups in 18-month joint space width or Kellgren-Lawrence scores.

CONCLUSIONS

These results suggest that a 10% weight loss in an overweight and obese osteoarthritic population elicits positive changes in the mechanical pathway to knee OA by having lower knee joint compressive loads during walking compared to low and no weight loss groups. The difference in compressive forces was due, in large part, to reductions in hamstring co-contraction during the initial portion of the stance phase.

The association of anthropometric measures and osteoarthritis knee in non-obese subjects: a cross sectional study

OBJECTIVE

Body mass index (BMI) and knee osteoarthritis have a strong association, but other anthropometric measures lack such associations. To date, no study has evaluated non-obese knee osteoarthritis to negate the systemic and metabolic effects of obesity. This study examines the validity of the contention that BMI and other anthropometric measures have a significant relationship with knee osteoarthritis.

METHODS

In total, 180 subjects with a diagnosis of knee osteoarthritis were recruited and classified according to Kellgren-Lawrence (KL) grades. Body mass index, mid-upper arm circumference, waist-hip ratio and triceps-skinfold thickness were recorded by standard procedures. Osteoarthritis outcome scores (WOMAC) were evaluated.

RESULTS

(1) In both genders, the BMI was significantly higher for KL grade 4 than for grade 2; triceps-skinfold thickness was positively correlated with the joint space width of the tibial medial compartment. (2) In males, triceps-skinfold thickness significantly increased as the KL grades moved from 2 to 4; the significantly higher BMI found in varus aligned knees was positively correlated with WOMAC scores. (3) In females, the waist-hip ratio was significantly higher for KL grade 4 than for grade 2; a significant correlation was found between BMI and WOMAC scores. The waist-hip ratio was significantly associated with varus aligned knees and it positively correlated with WOMAC scores and with the joint space width of the tibial medial compartment. The mid-upper arm circumference demonstrated no correlation with knee osteoarthritis. CONCLUS'ON: This study validates the contention that BMI and other anthropometric measures have a significant association with knee osteoarthritis. Contrary to common belief, the triceps-skinfold thickness (peripheral fat) in males and the waist-hip ratio (central fat) in females were more strongly associated with knee osteoarthritis than BMI.

Risk factors for radiographic tibiofemoral knee osteoarthritis: the wuchuan osteoarthritis study

Objective. To investigate the risk factors of radiographic tibiafemoral knee osteoarthritis (OA). Methods. A population-based cross-sectional survey was conducted in Wuchuan County. A questionnaire and bilateral weight-bearing posterior-anterior semi-flexed knee radiographs were completed and read for Kellgren and Lawrence (K/L) grade and joint space narrowing (JSN; 0-3 scale) in each compartment. An logistic regression analysis was performed for radiographic tibiafemoral, lateral compartment, and medial compartment knee OA, respectively. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated. Results. Age, sex, and knee injury were strongly associated with tibiafemoral, lateral and medial compartment knee OA. BMI also had a dose-response relationship with them. Physical activity level, and physical activity exposure at work, not significantly though, were associated with an elevated risk for this three kinds of knee OA. Conclusions. Physical activity exposure increased the risk of knee OA. It was likely to be the heavier physical activity in Wuchuan osteoarthritis study that counteracted the BMI gap compared with the Beijing and the Framingham OA study. We verified that Chinese had a more valgus alignment of the knee compared with Caucasian population, and this provide a possible explanation why Chinese have a higher prevalence of lateral compartment OA.

Development of a questionnaire for identification of the risk factors for osteoarthritis of the knees in developing countries. A pilot study in Iran and Bangladesh. An ILAR-COPCORD phase III study

BACKGROUND

Knee osteoarthritis (OA) is one of the most prevalent rheumatic disorders in the Asia-Pacific region. Identification of modifiable risk factors is important for development of strategies for primary and secondary prevention of knee OA.

OBJECTIVE

Developing a core questionnaire for identification of risk factors of knee OA at the community level.

METHODS

Steps performed: (1) item generation from literature, existing knee OA questionnaires and patient focus group discussions; (2) development of a preliminary APLAR-COPCORD English questionnaire; (3) translation into target language, back translation and development of a pre-final target language version; (4) adaptation of the pre-final target language version through tests of comprehensibility, content validity, test-retest reliability; and (5) finalization of the English questionnaire. Investigators in Bangladesh, Iran, China, Philippines and Indonesia participated in steps 1 and 2. Subsequent steps were carried out by Bangladeshi and Iranian investigators.

RESULTS

Fifty-three items were generated. Fourteen were obtainable from physical examination and placed in an examination sheet. Two radiological items were not included. A preliminary English questionnaire comprising the remaining 37 items was constructed and translated into Bengali and Persian. The preliminary Bengali and Persian versions were adapted as a result of tests of comprehensibility, content validity and test-retest reliability. The English questionnaire was adapted through repeated exchange of ideas and experiences among participating investigators. A 35-item English core questionnaire was finally developed.

CONCLUSION

The questionnaires may be used to identify risk factors of knee OA in Asia-Pacific communities after validation and further adaptation. From these data strategies for primary and secondary prevention of knee OA can be developed.

Cost-effectiveness of exercise and diet in overweight and obese adults with knee osteoarthritis

PURPOSE

The purpose of this study was to compare the cost-effectiveness of dietary and exercise interventions in overweight or obese elderly patients with knee osteoarthritis (OA) enrolled in the Arthritis, Diet, and Physical Activity Promotion Trial (ADAPT).

METHODS

ADAPT was a single-blinded, controlled trial of 316 adults with knee OA, randomized to one of four groups: Healthy Lifestyle Control group, Diet group, Exercise group, or Exercise and Diet group. A cost analysis was performed from a payer perspective, incorporating those costs and benefits that would be realized by a managed care organization interested in maintaining the health and satisfaction of its enrollees while reducing unnecessary utilization of health care services.

RESULTS

The Diet intervention was most cost-effective for reducing weight, at $35 for each percentage point reduction in baseline body weight. The Exercise intervention was most cost-effective for improving mobility, costing $10 for each percentage point improvement in a 6-min walking distance and $9 for each percentage point improvement in the timed stair climbing task. The Exercise and Diet intervention was most cost-effective for improving self-reported function and symptoms of arthritis, costing $24 for each percentage point improvement in subjective function, $20 for each percentage point improvement in self-reported pain, and $56 for each percentage point improvement in self-reported stiffness.

CONCLUSIONS

The Exercise and Diet intervention consistently yielded the greatest improvements in weight, physical performance, and symptoms of knee OA. However, it was also the most expensive and was the most cost-effective approach only for the subjective outcomes of knee OA (self-reported function, pain, and stiffness). Perceived function and symptoms of knee OA are likely to be stronger drivers of downstream health service utilization than weight, or objective performance measures and may be the most cost-effective in the long term.

The relationship between body mass index and hip osteoarthritis: a systematic review and meta-analysis

OBJECTIVE

Body mass index, a measure of relative weight, is increasingly recognized as an important risk factor for osteoarthritis, especially in weight bearing joints. The objective was to assess the association between body mass index and hip osteoarthritis susceptibility and investigate the difference between sex, study type and osteoarthritis definition.

METHODS

We did electronic searches of Medline, Embase and Cochrane library from the commencement to December 2009. A meta-analysis and meta-regression was executed to quantitatively assess the strength of associations between body mass index and hip osteoarthritis risk. Study-specific incremental estimates were standardized to determine the risk associated with a 5 kg/m(2) increase in body mass index.

RESULTS

Fourteen epidemiological studies were included. Our study showed that body mass index was significantly positive associated with hip osteoarthritis risk. A 5-unit increase in body mass index was related to an increased risk of hip osteoarthritis (RR: 1.11; 95%CI: 1.07, 1.16). The magnitudes of associations were similar in women as compared with men (women, RR: 1.10; 95%CI: 1.05, 1.15; men, RR: 1.08; 95%CI: 1.04, 1.12; p > 0.05). The summary estimates were 1.12 (95%CI: 1.02, 1.24) in case-control studies and 1.11 (95%CI: 1.06, 1.16) in cohort studies (p > 0.05). Body mass index was positively associated with hip osteoarthritis defined by radiography and/or clinical symptom (RR: 1.04; 95%CI: 1.00, 1.07) and clinical surgery (RR: 1.16; 95%CI: 1.11, 1.22) with no significant difference (p > 0.05).

CONCLUSION

Increased body mass index contributes to a positive effect on susceptibility to hip osteoarthritis. Associations between body mass index and hip osteoarthritis risk do not vary by sex, study design or osteoarthritis definition.

Obesity and disability in the symptomatic Irish knee osteoarthritis population

BACKGROUND

Osteoarthritis (OA) of the knee is a common disorder with significant social and financial implications. Obesity is the strongest modifiable risk factor of knee OA. There is little data on obesity in Irish knee OA populations and its relationship to other measures of disease severity.

AIMS

In Beaumont Hospital, we have been collecting data on patients presenting with knee OA as part of a screening process for potential candidates for therapeutic exercise intervention studies. Here, we present data on the first 96 candidates screened during this process.

RESULTS

The mean body mass index (BMI) of the group fell within the obese range (31); indeed, only 21% had a normal BMI. The vast majority of our patients had severe self-reported disability. In contrast, the distribution of radiographic severity of knee OA was more even. There was no significant relationship between radiographic severity and disability. BMI did predict disability but had a weak correlation. Radiographic severity did not correlate with BMI.

CONCLUSION

Irish patients with knee OA referred for physiotherapy were very disabled, significantly obese and represent a challenging cohort of patients to treat.

Pharmacology of morphine in obese patients: clinical implications

Morphine is an analgesic drug used to treat acute and chronic pain. Obesity is frequently associated with pain of various origins (e.g. arthritis, fibromyalgia, cancer), which increases the need for analgesic drugs. Obesity changes drug pharmacokinetics, and for certain drugs, specific modalities of prescription have been proposed for obese patients. However, scant data are available regarding the pharmacokinetics and pharmacodynamics of morphine in obesity. Prescription of morphine depends on pain relief but the occurrence of respiratory adverse effects correlates with obesity, and is not currently taken into account. Variations in the volume of distribution, elimination half-life and oral clearance of morphine, as well as recent advances in the respective roles of drug-metabolizing enzymes, catechol-O-methyltransferase and the mu opioid receptor in morphine pharmacokinetics and pharmacodynamics, may contribute to differences between obese and non-obese patients. In addition, drug-drug interactions may alter the disposition of morphine and its glucuronide metabolites, which may either increase the risk of adverse effects or reduce drug efficacy.

Psychosocial factors and the pain experience of osteoarthritis patients: new findings and new directions

PURPOSE OF REVIEW

The present paper reviews recent psychosocial research in the area of osteoarthritis pain. First, the review highlights studies of psychosocial factors that can influence osteoarthritis pain. Next, research testing the efficacy of psychosocial treatments for osteoarthritis pain is summarized.

RECENT FINDINGS

Recent studies suggest that asking osteoarthritis patients to recall pain experiences may not be as accurate as having them keep daily pain records. New studies also support the notion that fatigue and increased weight are linked to higher osteoarthritis pain. Osteoarthritis patients who report higher levels of depression are more prone to report increased osteoarthritis pain. New studies also indicate that social factors such as ethnic background, ability to communicate pain to others, and participation in social activities can influence osteoarthritis pain and disability. Cognitions about pain (i.e. pain catastrophizing, acceptance, self-efficacy for pain) also have been found to relate to pain in patients with osteoarthritis. Recent, randomized controlled studies suggest that psychosocial interventions (i.e. self-management programs, exercise) can decrease osteoarthritis pain and disability.

SUMMARY

Several psychosocial variables have been suggested as influencing osteoarthritis pain and disability. There is evidence that psychosocial interventions may decrease osteoarthritis pain and disability.

Prevalence of radiographic knee osteoarthritis and its association with knee pain in the elderly of Japanese population-based cohorts: the ROAD study

OBJECTIVE

We investigated the prevalence of radiographic knee osteoarthritis (OA) and knee pain in the Japanese elderly using a large-scale population of a nationwide cohort study, Research on Osteoarthritis Against Disability (ROAD), and examined their association.

METHODS

From the baseline survey of the ROAD study, 2,282 participants > or =60 years (817 men and 1,465 women) living in urban, mountainous and seacoast communities were analyzed. The radiographic severity at both knees was determined by the Kellgren/Lawrence (KL) grading system. KL> or =2 and KL> or =3 knee OA were examined separately to assess osteophytosis and joint space narrowing (JSN).

RESULTS

The prevalence of KL> or =2 OA (47.0% and 70.2% in men and women, respectively) was much higher than that of previous studies in Caucasians, while that of KL> or =3 OA was not much different in men. Age, BMI, female sex and rural residency were risk factors for radiographic knee OA, knee pain and their combination. The prevalence of knee pain was age-dependent in women, but not in men. Knee pain was more strongly associated with KL> or =3 OA than with KL=2, and the association was higher in men than in women. Female sex was a strong risk factor even in the subgroup without radiographic knee OA (KL=0/1).

CONCLUSION

The present cross-sectional study revealed a high prevalence of radiographic knee OA in the Japanese elderly. Knee pain was strongly associated with JSN especially in men, while women tended to have knee pain even without radiographic OA.

Reduced rates of primary joint replacement for osteoarthritis in Italian and Greek migrants to Australia: the Melbourne Collaborative Cohort Study

Introduction

Racial and ethnic disparities in rates of total joint replacement have been described, but little work has been done in well-established migrant groups. The aim of this study was to compare the rates of primary joint replacement for osteoarthritis for Italian and Greek migrants to Australia and Australian-born individuals.

Methods

Eligible participants (n = 39,023) aged 27 to 75 years, born in Italy, Greece, Australia and the United Kingdom, were recruited for the Melbourne Collaborative Cohort Study between 1990 and 1994. Primary hip and knee replacement for osteoarthritis between 2001 and 2005 was determined by data linkage to the Australian Orthopaedic Association National Joint Replacement Registry.

Results

Participants born in Italy and Greece had a lower rate of primary joint replacement compared with those born in Australia (hazard ratio [HR] 0.32, 95% confidence interval [CI] 0.26 to 0.39, P < 0.001), independent of age, gender, body mass index, education level, and physical functioning. This lower rate was observed for joint replacements performed in private hospitals (HR 0.17, 95% CI 0.13 to 0.23), but not for joint replacements performed in public hospitals (HR 0.96, 95% CI 0.72 to 1.29).

Conclusions

People born in Italy and Greece had a lower rate of primary joint replacement for osteoarthritis in this cohort study compared with Australian-born people, which could not simply be explained by factors such as education level, physical functioning, and weight. Although differential access to health care found in the population may explain the different rates of joint replacement, it may be that social factors and preferences regarding treatment or different rates of progression to end-stage osteoarthritis in this population are important to ethnic disparity.

Epidemiology of lumbar osteoporosis and osteoarthritis and their causal relationship--is osteoarthritis a predictor for osteoporosis or vice versa?: the Miyama study

SUMMARY

In a 10-year follow-up of a population-based cohort of Japanese subjects, incidences of and causal relationships between osteoporosis (OP) and osteoarthritis (OA) at the lumbar spine were clarified. OP might reduce the risk of subsequent OA at the spine in women, but not in men.

INTRODUCTION

The aim of this study is to clarify the contribution of osteoarthritis (OA) to osteoporosis (OP) and vice versa.

METHODS

A population-based, epidemiological study was conducted in a Japanese rural community. From 1,543 participants aged 40-79 years, 200 men and 200 women were selected and followed up for 10 years. Bone mineral density measurements were repeated after 3, 7, and 10 years, and X-rays were repeated after 10 years.

RESULTS

The incidence of lumbar OP per 10,000 person-years for persons in their 40s, 50s, 60s, and 70s was 0, 0, 109.5, and 151.1 for men and 124.2, 384.0, 227.3, and 239.5 for women, respectively. The cumulative incidence of lumbar OA over 10 years aged 40-79 years was 25.8% in men and 45.2% in women. Cox's proportional hazards model showed no significant relationship between the presence of lumbar OA at the baseline and incidence of lumbar and femoral neck OP in both genders. A significant relationship was demonstrated between the presence of lumbar OP, not femoral neck OP, at the baseline and cumulative incidence of lumbar OA in women (odds ratio, 0.20; 95% confidence interval, 0.05-0.80; P = 0.02).

CONCLUSION

OP in women appears to reduce the future incidence of OA at the lumbar spine.

Obesity and osteoarthritis: disease genesis and nonpharmacologic weight management

The mechanisms by which obesity affects osteoarthritis (OA) are of great concern to osteoarthritis researchers and clinicians who manage this disease. Inflammation and joint loads are pathways commonly believed to cause or to exacerbate the disease process. This article reviews the physiologic and mechanical consequences of obesity in older adults who have knee OA, the effects of long-term exercise and weight-loss interventions, the most effective nonpharmacologic treatments for obesity, and the usefulness and feasibility of translating these results to clinical practice.

Obesity influences transitional states of disability in older adults with knee pain

OBJECTIVES

This study employed relatively new statistical methods to understand how many states are needed to describe disability in older adults with knee pain, describe the relative probability of transitioning between states over time, and examine whether obesity influences the probability of transitioning between states.

DESIGN

Prospective epidemiologic study of older adults with knee pain.

SETTING

Community.

PARTICIPANTS

The participants, 245 women and 235 men, were 65 years or older, had chronic knee pain on most days, and had difficulty with at least 1 mobility-related activity caused by knee pain.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

The primary instrument, the Pepper Assessment Tool for Disability, evaluated self-reported difficulty with mobility, basic activities of daily living (ADLs), and instrumental activities of daily living (IADLs).

RESULTS

The Hidden Markov Model yielded 6 states reflecting changes in mobility, ADLs, and IADLs. There is evidence that loss in more demanding mobility-related activities such as stair climbing is an early sign for the onset of disability and that functional deficits in the lower extremities are critical to the early loss of ADLs. Overall the trend is for older adults to experience greater progression than regression and for obesity to be important in understanding severe states of disability.

CONCLUSIONS

These data provide a strong rationale for characterizing disability on a continuum and underscore the fluid nature of disability in older adults. As expected, lower-extremity function plays a key role in the disablement process; obesity is also particularly relevant to understanding severe states of disability.

Obesity and osteoarthritis in knee, hip and/or hand: an epidemiological study in the general population with 10 years follow-up

Background

Obesity is one of the most important risk factors for osteoarthritis (OA) in knee(s). However, the relationship between obesity and OA in hand(s) and hip(s) remains controversial and needs further investigation. The purpose of this study was to investigate the impact of obesity on incident osteoarthritis (OA) in hip, knee, and hand in a general population followed in 10 years.

Methods

A total of 1854 people aged 24–76 years in 1994 participated in a Norwegian study on musculoskeletal pain in both 1994 and 2004. Participants with OA or rheumatoid arthritis in 1994 and those above 74 years in 1994 were excluded, leaving n = 1675 for the analyses. The main outcome measure was OA diagnosis at follow-up based on self-report. Obesity was defined by a body mass index (BMI) of 30 and above.

Results

At 10-years follow-up the incidence rates were 5.8% (CI 4.3–7.3) for hip OA, 7.3% (CI 5.7–9.0) for knee OA, and 5.6% (CI 4.2–7.1) for hand OA. When adjusting for age, gender, work status and leisure time activities, a high BMI (> 30) was significantly associated with knee OA (OR 2.81; 95%CI 1.32–5.96), and a dose-response relationship was found for this association. Obesity was also significantly associated with hand OA (OR 2.59; 1.08–6.19), but not with hip OA (OR 1.11; 0.41–2.97). There was no statistically significant interaction effect between BMI and gender, age or any of the other confounding variables.

Conclusion

A high BMI was significantly associated with knee OA and hand OA, but not with hip OA.

Obesity and osteoarthritis: disease genesis and nonpharmacologic weight management

The mechanisms by which obesity affects osteoarthritis (OA) are of great concern to osteoarthritis researchers and clinicians who manage this disease. Inflammation and joint loads are pathways commonly believed to cause or to exacerbate the disease process. This article reviews the physiologic and mechanical consequences of obesity in older adults who have knee OA, the effects of long-term exercise and weight-loss interventions, the most effective nonpharmacologic treatments for obesity, and the usefulness and feasibility of translating these results to clinical practice.

Psychologic interventions and lifestyle modifications for arthritis pain management

This article provides an overview of self-management interventions used to manage pain in patients who have arthritis. The article is divided in two major sections. The first section reviews psychologic interventions used to manage arthritis pain, including pain-coping skills training and cognitive behavioral therapy for pain management, emotional disclosure interventions, and partner-assisted interventions. The second section addresses lifestyle behavioral weight loss interventions used to reduce arthritis pain. In each section, the authors briefly describe the rationale and nature of the interventions, present data on their efficacy, and highlight potential future research directions.