Osteoarthritis of the hip and occupational lifting

Labour's pain: strenuous subsistence work, mechanical wear-and-tear and musculoskeletal pain in a non-industrialized population

Musculoskeletal pain is the most debilitating human health condition. Neurophysiological pain mechanisms are highly conserved and promote somatic maintenance and learning to avoid future harm. However, some chronic pain might be more common owing to mismatches between modern lifestyles and traits that originally evolved under distinct premodern conditions. To inform assumptions about factors affecting chronic pain vulnerability prior to industrialization, we assess pain prevalence, perceived causes, and predictors among Tsimane forager-horticulturalists. Habitual subsistence work is the primary reported cause of pain throughout life for both sexes, and pain is more common with age, especially in the back, and for those with more musculoskeletal problems. Sex differences in pain are relatively weak, and we find no association between women's reproductive history and pain, contrary to the hypothesis that reproduction causes women's greater pain susceptibility. Age-standardized current pain prevalence is 1.7-8.2 times higher for Tsimane than other select populations, and Tsimane chronic pain prevalence is within the range of variation observed elsewhere. Chronic low back pain is not a 'mismatch disease' limited to post-industrialized populations. Hominin musculoskeletal changes supporting bipedalism probably imposed health costs, which, after millions of years of evolution, remain an epidemiological burden that may be exacerbated by modern conditions.

Highlighting the Benefits of Rehabilitation Treatments in Hip Osteoarthritis

Background and objectives: Due to its frequency and possible complications, hip arthrosis or hip osteoarthritis (hip OA) has a high social impact, its advanced stages eventually leading to irreversible lesions involving major complications or surgery. In the early stages, conservative treatment plays a key role in the prophylaxis of complications and in slowing down the degenerative process. The association between an appropriate drug therapy (DT) and a rehabilitation treatment (RT)—including individualized physical therapy (PT) and adapted occupational therapy (OT)—provides good results. Our objective was to highlight the benefits of associating RT with DT in patients with hip OA. Materials and Methods: An observational follow-up study was conducted between 2018−2021, which included 100 patients with hip OA divided into two groups: the study group—group A (50 subjects who complied with RT) and the control group—group B (who did not comply with RT). To evaluate them, the evolution of the Lequesne hip index (LHI), Tinetti test (TT) and the hip joint mobility: flexion (FH) and abduction (AH) were monitored before the beginning of the study (T0) and after one-year (T1) for each patient. The mean values of the parameters, the standard deviations, the frequency intervals, as well as the tests of statistical significance were calculated using the Student method (t-test) and χ2, ANOVA (Bonferroni) being used to compare the means. Results: Compared to the evolution of group B, improvements were observed in group A, as follows: in LHI group A (p = 0.023) vs. group B (p = 0.650); in TT group A (p = 0.011) vs. group B (p < 0.001); in FH group A (p = 0.001) vs. group B (p = 0.025); in AH group A (p = 0.001) vs. group B (p < 0.001). BMI changes were non-significant in both groups A (p = 0.223) and B (p = 0.513). Evaluating group A, the most significant improvements of the studied parameters were observed in the age group 41−50 years. Conclusions: The study reveals the benefits of combining RT with DT in patients with especially early-stage hip OA, aged up to 50 years old.

Exploring the factors affecting musculoskeletal disorders risk among hospital nurses

Background

Musculoskeletal disorder (MSD) is currently recognized as one of the most common occupational injuries for which nursing personnel in the medical service industry have been identified as a high-risk group. In this study, we explore the prevalence of MSD in various body parts as well as their risk factors among hospital nurses.

Methods

A cross-sectional descriptive design with stratified cluster sampling was used to collect data from 1,803 nurses. The survey included a demographic questionnaire, and Nordic Musculoskeletal Questionnaire.

Results

The results showed that the greatest prevalence of MSD symptoms by body regions were in the right shoulder (85.8%), the left shoulder (80.9%), the neck (62.4%), the right wrist (62.2%) and the lower back (60.4%). Risk factors for shoulder discomfort includes department type, exercise habits, and age (p < .05). Risk factors for neck discomfort includes seniority in the current unit, “job title, and “history of MDS (p < .05). Risk factors for upper back discomfort includes age and seniority in the current unit (p < .05). Risk factors for lower back discomfort including seniority in the current unit, department type, and number of days worked per week (p < .05).

Conclusions

The results of this study can serve as a reference for nursing administration managers and decision-makers for reducing musculoskeletal discomfort among nurses and thereby achieving superior quality in clinical care.

Household air pollution and arthritis in low-and middle-income countries: Cross-sectional evidence from the World Health Organization's study on Global Ageing and Adult Health

Background

Evidence points to a clear link between air pollution exposure and several chronic diseases though investigations regarding arthritis are still lacking. Emerging evidence suggests an association between ambient air pollution and rheumatoid arthritis. Household air pollution exposure, conversely, is largely unstudied but may be an important consideration for arthritis, particularly in low- and middle-income countries (LMICs), where cooking and heating activities can generate high indoor air pollutant levels.

Methods

We investigated the association of household air pollution (electricity vs. gas; kerosene/paraffin; coal/charcoal; wood; or agriculture/crop/animal dung/shrubs/grass as the main fuel used for cooking) and arthritis in six LMICs (China, Ghana, India, Mexico, the Russian Federation, South Africa) using data from Wave I of the World Health Organization Study on Global AGEing and Adult Health (SAGE) (2007–2010). Multivariable analyses were adjusted for sociodemographic, household and lifestyle characteristics and several comorbidities.

Results

The use of gas (aOR = 1.76, 95%CI: 1.40–2.21); coal (aOR = 1.74, 95%CI: 1.22–2.47); wood (aOR = 1.69, 95%CI: 1.30–2.19); or agriculture/crop/animal dung/shrubs/grass: aOR = 1.95 (1.46–2.61) fuels for cooking were strongly associated with an increased odds of arthritis, compared to electricity in cluster and stratified adjusted analyses. Gender (female), age (≥50 years), overweight (25.0 ≤BMI<30.0 kg/m²), obesity (BMI ≥30.0 kg/m²), former and current alcohol consumption, and the comorbidities angina pectoris, diabetes, chronic lung disease, depression and hypertension were also associated with a higher odds of arthritis. Underweight (BMI<18.5 kg/m²) and higher education levels (college/university completed/post-graduate studies) were associated with a lower odds of arthritis.

Conclusions

These findings suggest that exposure to household air pollution from cook fuels is associated with an increased odds of arthritis in these regions, which warrants further investigation.

Exposure-Response Relationship and Doubling Risk Doses-A Systematic Review of Occupational Workload and Osteoarthritis of the Hip

In this review, we critically evaluated the evidence of exposure–response relationships between occupational workload and the risk of hip osteoarthritis. The existing evidence was evaluated in order for us to extrapolate possible doubling risk doses for hip osteoarthritis. Comprehensive searches for epidemiological studies of hip osteoarthritis and occupational workload were performed in literature databases (PubMed, EMBASE, Cochrane Work and Google Scholar) and recent reviews up to February 2019. In total, 85 papers met the preliminary inclusion criteria, and 10 studies indicating an exposure-response relationship between occupational workload and hip osteoarthritis were identified. All studies were assessed on the basis of their study design, defined quality scores and relevant confounders considered. An exposure–response relationship between heavy lifting and the risk of hip osteoarthritis is consistently observed among the male populations but not among the female populations. We quantified the doubling risk doses in two studies in which both an exposure–response relationship and cumulative exposure doses were stated. These two studies provided the highest quality level of all studies published to date. The estimated doubling risk doses in these two studies lie between 14,761 and 18,550 tons (daily lifting 2.2–2.8 tons, 220 days/year for 30 years). These results can be used for workplace interventions to prevent hip osteoarthritis.

Geographical and ethnic differences of osteoarthritis-associated hip and knee replacement surgeries in New Zealand: a population-based cross-sectional study

OBJECTIVES

To (1) explore the regional and ethnic differences in rates of publicly funded osteoarthritis-associated hip and knee replacement surgeries and (2) investigate the mortality after surgery.

DESIGN

Population-based, retrospective, cross-sectional study.

SETTING

General population in New Zealand.

PARTICIPANTS

Patients with osteoarthritis who underwent publicly funded primary hip and knee replacement surgeries in 2005-2017. Patients aged 14-99 years were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

Age-standardised rate, standardised mortality ratio (SMR) and 30 days, 90 days and 1 year mortality.

RESULTS

We identified 53 439 primary hip replacements and 50 072 primary knee replacements with a diagnosis of osteoarthritis. The number and age-standardised rates of hip and knee replacements increased over time. Māori had the highest age-standardised rate of hip replacements, followed by European/others and Pacific, and Asian had the lowest rate. Pacific had the highest age-standardised rate of knee replacements, followed by Māori and European/others, and Asian had the lowest rate. The Northern Health Network had the lowest rate of hip surgeries, and the Southern Health Network had the lowest rate of knee surgeries. The SMRs of patients undergoing hip and knee replacements were lower than the general population: 0.92 (95% CI 0.89 to 0.95) for hip and 0.79 (95% CI 0.76 to 0.82) for knee. The SMRs were decreasing over time. The patterns of 30 days, 90 days and 1 year mortality were similar to the SMR.

CONCLUSIONS

The numbers of publicly funded osteoarthritis-associated primary hip and knee replacements are steadily increasing. Māori people had the highest age-standardised rate of hip replacements and Pacific people had the highest rate of knee replacements. The Northern Health Network had the lowest rate of hip surgeries, and the Southern Health Network had the lowest rate of knee surgeries. Compared with the general population, patients who had hip and knee replacements have a better life expectancy.

Qatar Biobank Cohort Study: Study Design and First Results

We describe the design, implementation, and results of the Qatar Biobank (QBB) cohort study for the first 10,000 participants. QBB is a prospective, population-based cohort study in Qatar, established in 2012. QBB's primary goal was to establish a cohort accessible to the local and international scientific community, providing adequate health data and biological samples to enable evidence-based research. The study design is based on an agnostic hypothesis, collecting data using questionnaires, biological samples, imaging data, and -omics. QBB aims to recruit 60,000 participants, men and women, adult (aged ≥18 years) Qataris or long-term residents (≥15 years living in Qatar) and follow up with them every 5 years. Currently, QBB has reached 28% (n = 17,065) of the targeted enrollee population and more than 2 million biological samples. QBB is a multinational cohort including 33 different nationalities, with a relatively young population (mean age, 40.5 years) of persons who are highly educated (50% university-educated) and have high monthly incomes. The 4 main noncommunicable diseases found among the QBB population are dyslipidemia, diabetes, hypertension, and asthma with prevalences of 30.1%, 17.4%, 16.8%, and 9.1%, respectively. The QBB repository can provide data and biological samples sufficient to demonstrate valid associations between genetic and/or environmental exposure and disease development to scientists worldwide.

Hip Osteoarthritis and Physical Workload: Influence of Study Quality on Risk Estimations-A Meta-Analysis of Epidemiological Findings

In this paper, we critically evaluate the quality of epidemiological evidence on hip osteoarthritis and workload published so far. The influence of study quality on risk estimations was analyzed in sensitivity meta-analyses and meta-regression analyses. Comprehensive searches for epidemiological studies of hip osteoarthritis and occupational workload were performed in literature databases and current reviews. All studies were assessed on the basis of study design, defined quality scores, and relevant confounders considered. In total, 34 suitable studies were identified for critical evaluation. Of these, 20 are prevalence studies and 14 incidence studies. Strong heterogeneity is observed in study design, quality level, and estimated exposure parameters. A consistent positive association between heavy physical workload and hip osteoarthritis was observed only among the male populations, not among the female populations. In general, cohort studies provided lower effect estimates than cross-sectional and population-based case-control studies. Studies with high quality scores also produced lower effect estimates than studies with low quality scores. Consideration of BMI as a confounder in published studies also yielded lower effect estimates than studies without consideration of BMI as a confounder. Our analyses indicate that high-quality studies of the association between occupational workload and hip osteoarthritis provide lower effect estimates than studies of lower quality.

Occupational Strain as a Risk for Hip Osteoarthritis

BACKGROUND

Multiple epidemiological studies have revealed an association between occupational physical strain and the risk of developing hip osteoarthritis.

METHODS

To determine the association between the lifting and carrying of heavy loads or other physically demanding work and the risk of hip osteoarthritis (HOA) or total hip replacement (THR), we systematically searched the literature for primary studies on the effects of exposure to physical strain and meta-analytically reviewed the results that were amenable to comparisons across studies. We separately assessed studies that had hip pain as an endpoint.

RESULTS

5 cohort studies and 18 case-control studies were found suitable for inclusion. The lifting of heavy loads increases the risk of HOA or THR: exposure doubles the risk in men (relative risk [RR] 2.09, 95% confidence interval [1.4; 3.1]) and increases it by roughly 40% in women (RR 1.41 [1.0; 1.9]). Physically demanding work consisting of a combination of activities of various kinds (dealing with heavy loads, heavy manual work, or prolonged walking and standing) increases the risk by roughly 150% in men (RR 2.46 [1.3; 4.8]) and 40% in women (RR 1.38 [0.9; 2.2]). Hip pain was also reported more commonly in the exposed groups.

CONCLUSION

The studies are moderately to highly heterogeneous. An association exists between years of lifting heavy loads or other kinds of physical strain on the job and the risk of developing osteoarthritis of the hip. The greater the exposure, the greater the risk. The evidence base for risk assessment in women is currently inadequate.

Dose-response relationship between cumulative physical workload and osteoarthritis of the hip - a meta-analysis applying an external reference population for exposure assignment

Background

There is consistent evidence from observational studies of an association between occupational lifting and carrying of heavy loads and the diagnosis of hip osteoarthritis. However, due to the heterogeneity of exposure estimates considered in single studies, a dose-response relationship between cumulative physical workload and hip osteoarthritis could not be determined so far.

Methods

This study aimed to analyze the dose-response relationship between cumulative physical workload and hip osteoarthritis by replacing the exposure categories of the included studies with cumulative exposure values of an external reference population. Our meta-regression analysis was based on a recently conducted systematic review (Bergmann A, Bolm-Audorff U, Krone D, Seidler A, Liebers F, Haerting J, Freiberg A, Unverzagt S, Dtsch Arztebl Int 114:581–8, 2017). The main analysis of our meta-regression comprised six case-control studies for men and five for women. The population control subjects of a German multicentre case-control study (Seidler A, Bergmann A, Jäger M, Ellegast R, Ditchen D, Elsner G, Grifka J, Haerting J, Hofmann F, Linhardt O, Luttmann A, Michaelis M, Petereit-Haack G, Schumann B, Bolm-Audorff U, BMC Musculoskelet Disord 10:48, 2009) served as the reference population. Based on the sex-specific cumulative exposure percentiles of the reference population, we assigned exposure values to each category of the included studies using three different cumulative exposure parameters. To estimate the doubling dose (the amount of physical workload to double the risk of hip osteoarthritis) on the basis of all available case-control-studies, meta-regression analyses were conducted based on the linear association between exposure values of the reference population and the logarithm of reported odds ratios (ORs) from the included studies.

Results

In men, the risk to develop hip osteoarthritis was increased by an OR of 1.98 (95% CI 1.20–3.29) per 10,000 tons of weights ≥20 kg handled, 2.08 (95% CI 1.22–3.53) per 10,000 tons handled > 10 times per day and 8.64 (95% CI 1.87–39.91) per 10⁶ operations. These estimations result in doubling dosages of 10,100 tons of weights ≥20 kg handled, 9500 tons ≥20 kg handled > 10 times per day and 321,400 operations of weights ≥20 kg. There was no linear association between manual handling of weights at work and risk to develop hip osteoarthritis in women.

Conclusions

Under specific conditions, the application of an external reference population allows for the derivation of a dose-response relationship despite high exposure heterogeneities in the pooled studies.

Electronic supplementary material

The online version of this article (10.1186/s12891-018-2085-8) contains supplementary material, which is available to authorized users.

Physical workload is associated with increased risk of rheumatoid arthritis: results from a Swedish population-based case-control study

Objectives

This study investigated: (1) the association of physical workload (PW) and risk of rheumatoid arthritis (RA); (2) the potential interactions between PW and the genes in the human leucocyte antigen (HLA) region.

Methods

A population-based case–control study involving incident cases of RA (3150 cases and 5130 controls) was performed using data from the Swedish Epidemiological Investigation of Rheumatoid Arthritis. Information on 7 types of self-reported PW exposure and HLA-DRB1 genotypes of cases and controls were gathered. Anticitrullinated protein antibody (ACPA) status of cases was identified. For each PW exposures, exposed participants were compared with unexposed participants. ORs with 95% CIs of RA (overall), ACPA-positive RA and ACPA-negative RA associated with different PWs were estimated using logistic regression. HLA-PW interactions were estimated using the principle of departure from additivity of effects by calculating attributable proportion (AP) due to interaction.

Results

ORs of developing RA associated with 6 various PW exposures ranging from 1.3 (95% CI 1.1 to 1.4) to 1.8 (95% CI 1.6 to 2.0) were observed. Exposure to more types of PW was associated with increasing risk for RA (p<0.0001). No major difference in the ORs between ACPA-positive and ACPA-negative RA was found. For some exposures, we found evidence of interactions between PW and the HLA-DRB1 shared epitope genes, regarding risk of ACPA-positive RA (AP: from 0.3 (95% CI 0.1 to 0.5) to 0.4 (95% CI 0.2 to 0.6)).

Conclusions

PW is associated with the risk of ACPA-positive and ACPA-negative RA. Interactions between PW and the HLA-DRB1 shared epitope were found in ACPA-positive RA.

Kinematics of meniscal- and ACL-transected mouse knees during controlled tibial compressive loading captured using roentgen stereophotogrammetry

Pre-clinical studies of post-traumatic OA have examined the pathways that lead to disease after injury by using surgical models such as the destabilization of the medial meniscus (DMM) and anterior cruciate ligament transection (ACLT). While the morphological, molecular, and genetic pathways leading to OA have been examined extensively; the effects of these injuries on joint kinematics, and thus disease progression, have yet to be fully characterized. To this end, we sought to understand the kinematics in the DMM and ACLT joints compared to intact joints subjected to controlled tibial compressive loading. We hypothesized that the DMM and ACLT models would result in different patterns of joint instability compared to intact joints, thus explaining the different patterns of OA initiation and severity in these models. Cadaver adult C57BL/6 mice were subjected to either a DMM or ACLT in their right knee joints, while the left limbs remained as intact controls. All limbs were labeled with fiducial markers, and the rigid body kinematics of the tibia and femur were examined using roentgen stereophotogrammetry (RSA) with application of compressive loads from 0 to 9 N. DMM and intact joints demonstrated similar kinematics under compressive loading, in contrast to ACLT joints, which dislocated even before load application. These results demonstrate the importance of rigorous kinematic analysis in defining the role of joint instability in animal models of OA and suggest significant differences in DMM and ACLT joint instabilities in the context of controlled mechanical loading. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:353-360, 2017.

Factors associated with functional limitations in the daily living activities of Japanese hip osteoarthritis patients

AIM

As society ages, there is a vast number of elderly people with locomotive syndrome. In this study, the factors associated with functional limitations in daily living activities evaluated by female hip osteoarthritis (OA) patients were investigated.

METHODS

This study was a cross-sectional study. The subjects were 353 female patients who were newly diagnosed with hip OA at an orthopedic clinic with no history of hip joint surgery. Outcome indices were functional limitations in two daily living activities obtained from a questionnaire completed by the patients: (i) standing up (standing from a crouched position) and (ii) stair-climbing (climbing and/or descending stairs). The odds ratios (ORs) and 95% confidence intervals (CIs) were computed for explanatory variables using the proportional odds model in logistic regression to evaluate their associations with functional limitations.

RESULTS

Functional limitations in standing up were associated with heavy weight (third tertile vs. first tertile: 1.91, 1.11-3.27), participation in sports at school (0.62, 0.40-0.98), parity (vs. nullipara: 1.96, 1.08-3.56), old age and OA stage. Associations with functional limitations in stair-climbing were seen with short height (< 151.0 cm vs. ≥ 156.0 cm: 2.05, 1.02-4.12), bilateral involvement (vs. unilateral: 1.71, 1.01-2.88), old age and OA stage.

CONCLUSION

Old age, OA stage, heavy weight, parity, shorter height and bilateral OA were associated with functional limitations in standing up and/or stair-climbing, whereas participation in sports such as club activities in school maintained standing up.

Osteoarthritis and the Tactical Athlete: A Systematic Review

OBJECTIVE

 Although tactical athletes (eg, military service members, law enforcement personnel, fire fighters) are exposed to several known risk factors, it remains unclear if they are at increased risk for osteoarthritis (OA). The purpose of this systematic review was to investigate the association between serving as a tactical athlete and the incidence and prevalence of OA.

DATA SOURCES

 We completed a comprehensive systematic literature search in November 2014 using 12 bibliographic databases (eg, PubMed, Ovid, SportDiscus) supplemented with manual searches of reference lists.

STUDY SELECTION

 Studies were included if they met the following criteria: (1) an aim of the study was to investigate an association between tactical athletes and OA; (2) the outcome measure was radiographic OA, clinical OA, total joint replacement, self-reported diagnosis of OA, or placement on a waiting list for a total joint replacement; (3) the study design was a cohort study; and (4) the study was written in English.

DATA EXTRACTION

 One investigator extracted data from articles that met all inclusion criteria (eg, group descriptions, measures of disease burden, source of nonexposed controls).

DATA SYNTHESIS

 Twelve articles met the inclusion criteria and described retrospective cohort studies. Firefighters, active-duty military service members, and veteran military parachutists consistently had a higher incidence or prevalence of knee, hip, or any OA diagnosis (4 studies). Active-duty pilots and veteran military parachutists may have a higher prevalence of spine OA, but this was not statistically significant (2 studies). Occupational risk factors for OA among tactical athletes include rank and branch of military service. The risk of OA among individuals who completed mandatory national military service remains unclear (6 studies).

CONCLUSIONS

 The incidence of OA among tactical athletes appears to be significantly higher when compared with nonexposed controls. Further research is needed to specifically identify modifiable risk factors within this high-risk population to develop and implement effective risk-reduction strategies.

HIP osteoarthritis and work

Epidemiological evidence points strongly to a hazard of hip osteoarthritis from heavy manual work. Harmful exposures may be reduced by the elimination or redesign of processes and the use of mechanical aids. Reducing obesity might help to protect workers whose need to perform heavy lifting cannot be eliminated. Particularly high relative risks have been reported in farmers, and hip osteoarthritis is a prescribed occupational disease in the UK for long-term employees in agriculture. Even where it is not attributable to employment, hip osteoarthritis impacts importantly on the capacity to work. Factors that may influence work participation include the severity of disease, the physical demands of the job, age and the size of the employer. Published research does not provide a strong guide to the timing of return to work following hip arthroplasty for osteoarthritis, and it is unclear whether patients should avoid heavy manual tasks in their future employment.

Total hip replacement due to primary osteoarthritis in relation to cumulative occupational exposures and lifestyle factors: a nationwide nested case-control study

OBJECTIVE

To investigate the risk of total hip replacement (THR) due to primary osteoarthritis in relation to cumulative occupational mechanical exposures and lifestyle factors.

METHODS

Using register information, we identified first-time THR cases within the Danish working population in 2005-2006. For each case, 2 age- and sex-matched controls were drawn. Persons within 2,500 randomly selected case-control sets received a questionnaire about job history, weight at age 25 years, present weight and height, smoking, and sports activities at age 25 years. The job history was combined with a job exposure matrix. Cumulative exposure estimates were expressed according to the pack-year concept of smoking (e.g., cumulative lifting was expressed as ton-years). We used conditional logistic regression for statistical analyses.

RESULTS

In total, 1,776 case-control sets (71%) were available for analysis. The adjusted odds ratio (OR) for exposure to ≥20 ton-years was 1.35 (95% confidence interval [95% CI] 1.05-1.74) for men and 1.00 (95% CI 0.73-1.41) for women. Standing/walking and whole body vibration showed no associations. The adjusted OR for body mass index (BMI) ≥30 kg/m(2) at age 25 years was 2.44 (95% CI 1.38-4.32) for men and 5.12 (95% CI 2.30-11.39) for women. The corresponding adjusted ORs for an increase in BMI of ≥10 kg/m(2) since age 25 years were 2.16 (95% CI 1.25-3.70) and 2.46 (95% CI 1.47-4.13). Sports participation showed weak positive associations, while pack-years of smoking showed no associations.

CONCLUSION

The results indicated a modest increase in risk of THR in relation to cumulative lifting among men and an increased risk in relation to a high BMI at age 25 years and to a gain in BMI in both sexes.

Occupational risk factors for hip osteoarthritis are associated with early hip structural abnormalities: a 3.0 T magnetic resonance imaging study of community-based adults

Introduction

Occupational exposure to heavy lifting and stair climbing are associated with radiographic hip osteoarthritis (OA). This study examined whether these activities are associated with early structural hip joint changes in a community-based population.

Methods

In total, 198 community-based people with no history of hip disease, including OA, had 3.0 T-magnetic resonance imaging (MRI) to assess hip cartilage volume, defects and bone marrow lesions (BMLs). Recall of occupational exposure to heavy lifting and stair climbing aged 18 to 30 years and in the previous 10 years were collected. A persistence score was defined as exposure at neither time point (0), at one time point (1) or at both time points (2).

Results

Exposure to heavy lifting when aged 18 to 30 years was associated with BMLs of the central superolateral femoroacetabular region (odds ratio (OR) 3.9, 95% confidence interval (CI) 1.6 to 9.8, P <0.01), with persistence score associated with cartilage defects in the central superolateral region of the femoral head (OR 1.6, 95% CI 1.0 to 2.5, P = 0.04). Exposure to stair climbing aged 18 to 30 years and persistence score were associated with an increased risk of cartilage defects in the central superolateral femoral head and BMLs in the central superolateral and posterior femoroacetabular regions (OR range 2.1 to 3.2, all P ≤0.03).

Conclusions

Occupational exposure to heavy lifting and stair climbing are associated with hip structural abnormalities. If confirmed by longitudinal data, such associations may explain how occupational activities affect the hip joint and may identify new targets for the prevention of hip OA.

The Association between a History of Parental Addictions and Arthritis in Adulthood: Findings from a Representative Community Survey

Aims. To examine the relationship between a history of parental addictions and the cumulative lifetime incidence of arthritis while controlling for age, sex, race, and four clusters of risk factors: (1) other adverse childhood experiences, (2) adult health behaviors (i.e., smoking, obesity, inactivity, and alcohol consumption), (3) adult socioeconomic status and (4) mental health. Materials and Methods. Secondary analysis of 13,036 Manitoba and Saskatchewan respondents of the population-based 2005 Canadian Community Health Survey. Sequential logistic regression analyses were conducted. Findings. After controlling for demographic characteristics, including age, gender, and race, respondents who reported a history of parental addictions had significantly higher odds of arthritis in comparison to individuals without (OR=1.58; 95% CI 1.38–1.80). Adjustment for socioeconomic status, adult health behaviors, and mental health conditions had little impact on the parental addictions and arthritis relationship. The association between parental addictions and arthritis was substantially reduced when adverse childhood experiences (OR=1.33; 95% CI 1.15–1.53) and all four groups of risk factors collectively (OR=1.30; 95% CI = 1.12–1.51) were included in the analyses; however, the relationship remained statistically significant. Conclusions. A robust association was found between parental addictions and cumulative lifetime incidence of arthritis. This link remained even when controlling for four groups of potential risk factors.

Knee laxity after staircase exercise predicts radiographic disease progression in medial compartment knee osteoarthritis

OBJECTIVE

To evaluate whether increased laxity of the knee during daily physical activities such as stair climbing is associated with progression of knee joint osteoarthritis (OA).

METHODS

During the years 2001-2003, 136 patients with bilateral primary medial compartment knee joint OA were enrolled in this prospective study. Baseline data collected were body mass index (BMI), muscle power, radiographic joint space width, mechanical axis on standing radiography, and anteroposterior (AP) knee laxity before and after physical exercise. After 8 years of followup, 84 patients were reexamined to assess radiographic changes. Radiographic disease progression was defined as progression of >1 grade on the Kellgren/Lawrence scale.

RESULTS

AP knee laxity increased significantly after stair climbing. Patients with OA progression and those without progression did not differ significantly in age, sex, baseline quadriceps muscle strength, mechanical axis, joint space width, and AP knee laxity before exercise. The 2 groups of patients did, however, differ significantly in baseline BMI and change in AP knee laxity due to exercise. The risk of progression of knee OA increased 4.15-fold with each millimeter of increase in the change in AP knee laxity due to exercise and 1.24-fold with each point increase in the BMI.

CONCLUSION

Our results indicate that patients with OA progression have significantly greater changes in knee joint laxity during physical activities and a higher BMI than patients without OA progression. These findings suggest that larger changes in knee laxity during repetitive physical activities and a higher BMI play significant roles in the progression of knee OA.

The ratio of thoracic to lumbar compression force is posture dependent

Despite the evidence suggesting that between 8% and 55% of manual labourers experience thoracic pain, research on spinal loading during occupational tasks has been almost invariably limited to the lumbar spine. In this study, we determined the ratio of thoracic to lumbar compression force and the relative risk of injury to each region in various postures. Compressive forces on the spine were calculated based on previously reported thoracic and lumbar intradiscal pressures and disc cross-sectional areas. Flexion postures were associated with an approximate doubling in lumbar compression force but only small increases (or even decreases) in thoracic compression. The ratio of thoracic to lumbar compression was above the tolerance ratio (i.e. the ratio of thoracic to lumbar compressive strength) during upright postures and below the tolerance ratio during flexion postures, indicating that upright postures may pose a greater relative risk of injury to the thoracic spine than to the lumbar spine. Practitioner summary: Previously reported thoracic and lumbar in vivo disc pressures during various postures were compared. The ratio of thoracic and lumbar compression increased during upright postures and decreased in flexed postures, indicating that upright postures may pose a greater risk of injury to the thoracic spine than to the lumbar spine.

The osteoarthritic niche and modulation of skeletal stem cell function for regenerative medicine

Osteoarthritis (OA) is the most common cause of arthritis worldwide and represents a significant healthcare burden, particularly in the context of an ageing population. Traditionally, painkillers, injections and physiotherapy have been the mainstay of treatment, with patients being referred for joint replacement surgery (arthroplasty) when these options fail. Whilst effective in reducing pain and improving joint function, these approaches are not without potential complications. With the development of tissue-engineering techniques over recent years there has been considerable interest in applying these strategies to provide new, innovative, alternative effective means of treating OA. This review explores the unique microenvironment present within an osteoarthritic joint, highlighting the features that comprise the osteoarthritic niche and could be modulated in the development of novel treatments for OA. Existing tissue-engineering strategies for repairing bone and cartilage defects are discussed, with particular reference to how these might be modified, both to improve existing treatments, such as impaction bone grafting, as well as in the development of future treatments for OA.

Epidemiological evidence for work load as a risk factor for osteoarthritis of the hip: a systematic review

Objective

Osteoarthritis of the hip (OA) is a common degenerative disorder of the joint cartilage that presents a major public health problem worldwide. While intrinsic risk factors (e.g, body mass and morphology) have been identified, external risk factors are not well understood. In this systematic review, the evidence for workload as a risk factor for hip OA is summarized and used to derive recommendations for prevention and further research.

Methods

Epidemiological studies on workload or occupation and osteoarthritis of the hip were identified through database and bibliography searches. Using pre-defined quality criteria, 30 studies were selected for critical evaluation; six of these provided quantitative exposure data.

Results

Study results were too heterogeneous to develop pooled risk estimates by specific work activities. The weight of evidence favors a graded association between long-term exposure to heavy lifting and risk of hip OA. Long-term exposure to standing at work might also increase the risk of hip OA.

Conclusions

It is not possible to estimate a quantitative dose-response relationship between workload and hip OA using existing data, but there is enough evidence available to identify job-related heavy lifting and standing as hazards, and thus to begin developing recommendations for preventing hip OA by limiting the amount and duration of these activities. Future research to identify specific risk factors for work-related hip OA should focus on implementing rigorous study methods with quantitative exposure measures and objective diagnostic criteria.

The Effect of Osteoarthritis of the Hip or Knee on Work Participation

In our systematic literature search, we included studies involving patients with hip or knee osteoarthritis (OA) and outcome measures of work participation. Methodological quality was assessed using 11 criteria; a qualitative data analysis was performed. Fifty-three full-text articles were selected out of 1861 abstracts; finally, data were extracted from 14 articles. Design, populations, definitions, and measurements in the studies showed large variations; work outcomes were often only secondary objectives. The outcomes were summarized as showing a mild negative effect of OA on work participation. Many patients had paid work and managed to stay at work despite limitations. However, research on the effect of OA on work participation is scarce and the methodological quality is often insufficient. The longitudinal course of work participation in individuals with OA has not been described completely.

Descriptive epidemiology of mechanical hip pathology in adults under 50 years of age. Prospective series of 292 cases: Clinical and radiological aspects and physiopathological review

Two hundred and ninety-two patients, aged between 16 and 50 years and presenting with mechanical hip pathology, were included in a prospective multicenter study. The descriptive study concerned the clinical examination and analysis of three X-ray views (AP pelvic, Lequesne false profile and lateral axial view). The series comprised 62% males, mean age 35 years, with 53% right side and 22% bilateral involvement. Initial trauma was reported in 19% of cases, and direct familial history of hip pathology in 20%. Seventy percent of the patients played sports, 30% were high-level athletes, and 17% played combat sports. The physical impingement sign was present in 18% to 65% of cases depending on the variant studied. On imaging (n=241), 62% of hips showed osteoarthritis, with 25% at the evolved stage. In the series, as a whole, there was a 35% rate of dysplasia, 63% of impingement and 5% of normal X-ray results. The radiologic impingement aspects were 58% cam-type, 19% pincer-type and 23% mixed. Twenty-two percent of dysplasia cases showed signs of associated impingement. Pain experienced exclusively in flexion/internal rotation/adduction on examination showed little sensitivity (20%) but considerable specificity (86%) for the main diagnosis of impingement. The links between impingement and dysplasia are discussed, and an integrative schema of all risk factors is put forward.

Association between occupation and knee and hip replacement due to osteoarthritis: a case-control study

Introduction

The objective of this study was to examine the association between occupation and osteoarthritis (OA) leading to total knee (TKR) or hip (THR) joint replacement.

Methods

The following is the case-control study design. All patients still living in Iceland who had had a TKR or THR due to OA as of the end of 2002 were invited to participate. First degree relatives of participating patients served as controls. N = 1,408 cases (832 women) and n = 1,082 controls (592 women), 60 years or older and who had adequately answered a questionnaire were analyzed. Occupations were classified according to international standards. Inheritance of occupations was calculated by using the Icelandic Genealogy Database.

Results

The age adjusted odds ratio (OR) for male farmers getting a TKR due to OA was 5.1 (95% confidence interval (CI) 2.1 to 12.4) and for a male farmer getting a THR due to OA the OR was 3.6 (95% CI 2.1 to 6.2). The OR for a fisherman getting a TKR was 3.3 (95% CI 1.3 to 8.4). No other occupations showed increased risk for men. For women there was no increased risk for any occupation. Farming and fishing were also the occupations that showed the greatest degree of inheritance.

Conclusions

These results support an association in males between occupations with heavy physical load and both TKR and THR for OA.

Associations of occupational tasks with knee and hip osteoarthritis: the Johnston County Osteoarthritis Project

OBJECTIVE

This cross-sectional study examined associations of occupational tasks with radiographic and symptomatic osteoarthritis (OA) in a community-based sample.

METHODS

Participants from the Johnston County Osteoarthritis Project (n = 2729) self-reported the frequency of performing 10 specific occupational tasks at the longest job ever held (never/seldom/sometimes vs often/always) and lifetime exposure to jobs that required spending > 50% of their time doing 5 specific tasks or lifting 22, 44, or 110 pounds 10 times weekly. Multivariable logistic regression models examined associations of each occupational task separately with radiographic and symptomatic knee and hip OA, controlling for age, race, gender, body mass index, prior knee or hip injury, and smoking.

RESULTS

Radiographic hip and knee OA were not significantly associated with any occupational tasks, but several occupational tasks were associated with increased odds of both symptomatic knee and hip OA: lifting > 10 pounds, crawling, and doing heavy work while standing (OR 1.4-2.1). More occupational walking and standing and less sitting were also associated with symptomatic knee OA, and more bending/twisting/reaching was associated with symptomatic hip OA. Exposure to a greater number of physically demanding occupational tasks at the longest job was associated with greater odds of both symptomatic knee and hip OA.

CONCLUSION

Our results confirm an association of physically demanding occupational tasks with both symptomatic knee and hip OA, including several specific activities that increased the odds of OA in both joint groups. These tasks represent possibilities for identifying and targeting at-risk individuals with preventive interventions.

Survival of primary total hip arthroplasty in rheumatoid arthritis patients

BACKGROUND AND PURPOSE

There has been a limited amount of research on survival of total hip arthroplasties (THAs) in rheumatoid arthritis (RA). We therefore performed a population-based, nationwide study to compare the survival of primary THAs in RA patients and in osteoarthritis (OA) patients. We also wanted to identify predictors of THA failure in RA patients.

METHODS

Using the Danish Hip Arthroplasty Registry, we identified 1,661 primary THAs in RA patients and 64,858 in OA patients, all of which were inserted between 1995 and 2008. The follow-up period was up to 14 years for both groups.

RESULTS

Regarding overall THA survival, the adjusted RR for RA patients compared to OA patients was 0.81 (95% CI: 0.65-1.01). We found no difference in survival of cups between primary THAs in RA and OA patients. In contrast, there was better overall survival of stems in RA patients than in OA patients, both regarding revision due to aseptic loosening (adjusted RR = 0.58; 95% CI: 0.34-0.99) and for any reason (adjusted RR = 0.63; 95% CI: 0.45-0.88). In RA patients, males had a higher risk of revision than females concerning aseptic loosening of the stem, any revision of the stem, and any revision of both components.

INTERPRETATION

The overall survival of primary THAs in RA patients is similar to THA survival in OA patients. Stem survival appeared to be better in RA patients, while survival of the total THA concept did not show any statistically significant differences between the two groups. In RA patients, males appear to have a greater risk of revision than females.

The robust association between childhood physical abuse and osteoarthritis in adulthood: findings from a representative community sample

OBJECTIVE

Research suggests a role of early-life trauma in the development of arthritis. This study investigated the relationship between childhood physical abuse and osteoarthritis (OA) while controlling for age, sex, race, and socioeconomic status (SES), in addition to the following types of risk factors for OA: 1) concurrent childhood stressors, 2) adult health behaviors, and 3) depression.

METHODS

Data from the provinces of Manitoba and Saskatchewan were selected from the 2005 Canadian Community Health Survey (n = 13,093). Respondents with missing arthritis data or with arthritis types other than OA were excluded (n = 1,985). Of the 11,108 remaining respondents, 6.9% (n = 854) reported childhood physical abuse by someone close to them, and 10.1% (n = 1,452) reported that they had been diagnosed with OA by a health professional. The regional-level response rate was 84%.

RESULTS

When adjusting for all 3 types of risk factors, a significant association between childhood physical abuse and OA was found (odds ratio [OR] 1.56, 95% confidence interval [95% CI] 1.21-2.00). In contrast, when adjusting for age, sex, race, and SES only, the OR was 1.99 (95% CI 1.57-2.52).

CONCLUSION

The association between childhood physical abuse and OA remained significant, even after controlling for many risk factors that may mediate the relationship. Further research is needed to investigate potential pathways through which arthritis develops as a consequence of childhood physical abuse.

Body mass index and premature mortality in physically heavily working men--a ten-year follow-up of 20,000 construction workers

OBJECTIVE

Although obesity is clearly associated with diabetes and cardiovascular disease, health consequences of being mildly or moderately overweight are less clear in physically heavily working men.

METHODS

The association between body mass index (BMI) and mortality was assessed over a 10-year period in a cohort of 19,513 male construction workers, who underwent routine occupational health examination during 1986 to 1992.

RESULTS

Among never smokers normal and overweight men experienced similar mortality. Among smokers, we observed a strong U-shaped association between BMI and all-cause mortality, which was lowest for BMI levels between 25 and 35 kg/m after control for potential covariates.

CONCLUSIONS

BMI levels commonly considered to reflect overweight may not necessarily be associated with increased mortality in physically heavily working men.

Factors influencing osteological changes in the hands and fingers of rock climbers

This study examines the osteological changes in the hands and fingers of rock climbers that result from intense, long-term mechanical stress placed on these bones. Specifically, it examines whether rock climbing leads to metacarpal and phalange modelling in the form of increased cortical thickness as well as joint changes associated with osteoarthritis. This study also attempts to identify specific climbing-related factors that may influence these changes, including climbing intensity and frequency of different styles of climbing. Radiographs of both hands were taken for each participant and were scored for radiographic signs of osteoarthritis using an atlas method. Total width and medullary width were measured directly on radiographs using digital calipers and used to calculate cross-sectional area and second moment of area based on a ring model. We compared 27 recreational rock climbers and 35 non-climbers for four measures of bone strength and dimensions (cross-sectional area, second moment of area, total width and medullary width) and osteoarthritis. A chi-squared test for independence was used to compare climber and non-climber osteoarthritis scores. For each measure of bone strength climbers and non-climbers were compared using a manova test. Significant manova tests were followed by principal components analysis (PCA) and individual anova tests performed on principal components with eigenvalues greater than one. A second PCA was performed on the climber subsample and the first principal component was then used as the dependent variable in linear regression variable selection procedures to determine which climbing-related variables affect bone thickness. The results suggest that climbers are not at an increased risk of developing osteoarthritis compared with non-climbers. Climbers, however, do have greater cross-sectional area as well as second moment of area. Greater total width, but not meduallary width, indicates that additional bone is deposited subperiosteally. The strength of the finger and hand bones are correlated with styles of climbing that emphasize athletic difficulty. Significant predictors include the highest levels achieved in bouldering and sport climbing.

Factors affecting the prevalence of osteoarthritis in healthy middle-aged women: data from the longitudinal Melbourne Women's Midlife Health Project

The prevalence of osteoarthritis (OA) is greater in women then men. Weight, a factor strongly associated with osteoarthritis, is significantly increased over the menopausal transition. Despite the high prevalence of osteoarthritis, a disabling disease with limited treatment options, there is a paucity of studies in women. The longitudinal phase of the Melbourne Women's Midlife Health Project, is a population-based prospective study of 438 Australian born women who have been followed annually over 11 years. 257 (59%) of these women remained in longitudinal assessment at 11th year of follow-up and 224 of these women agreed to undergo X-rays of their knees and hands. In this study, X-rays were scored for evidence of osteoarthritis using a validated scale, by two investigators who were blinded to questionnaire results. Information on hormone therapy use, physical activity, smoking, BMI and age were obtained by both self-administered and face-to-face questionnaires. Results showed that one hundred and twenty-eight women (56%) had evidence of radiological OA. Forty-nine (21.6%) had evidence of radiological knee OA. One hundred and one (44.5%) had evidence of radiological hand OA. Compared to baseline, at 11th year of follow-up participants had put on weight (4 kg range -14 to 25 kg) and a larger proportion (25% vs. 40%) reported exercising frequently (P = 0.005). Physical activity and BMI were associated with higher prevalence of osteoarthritis in the final year of follow-up. Smoking was associated with a lower prevalence of radiological knee OA. The prevalence was 61% among never smokers compared to only 39% among those who smoked (P < 0.05). Total OA was associated with never having used hormone therapy (odds ratio 2.7; CI 1.1-6.9). There was a trend for increasing level of physical activity at ages 20-29 to be associated with an increased risk of knee OA (P value 0.03 for trend). In conclusion increasing age, BMI and history of more frequent physical activity in younger years were risk factors for radiological knee OA. In contrast, smoking appeared to be associated with less knee OA. Never having used hormone therapy was a risk factor for radiological hand and knee OA. Further work will be needed to determine whether modification of these factors can prevent the development of OA.

The course and prognosis of hip complaints in general practice

BACKGROUND

The general practitioner needs to discriminate complaints with need of specialist care from those that can be managed in primary care. However, no previous research has studied prognostic indicators for the course of hip complaints in a primary care population.

PURPOSE

The purpose of this study was to investigate the course of hip complaints presented in general practice and to identify relevant prognostic indicators of outcome.

METHODS

Data were collected by means of self-administered questionnaires containing questions about sociodemographic variables, characteristics of the complaints, and several intraindividual and extraindividual factors, including several psychosocial variables (e.g., pain coping, distress, and kinesiophobia). After 3 and 12 months of follow-up perceived recovery, change in pain intensity and change in functioning were assessed. Multiple regression analyses were performed to investigate the association between the potential prognostic indicators and the 3 outcome measures.

RESULTS

We included 139 patients with hip complaints, presented in general practice. Only 24% reported recovery after 3 months, increasing to 37% after 12 months. A history of hip complaints, a longer duration of the current episode of hip complaints, or more severe complaints, were associated with a less favorable prognosis. Furthermore, more vital patients and patients who met the Norm for Healthy Activity had a higher probability of a favorable outcome. Pain transformation and worrying were significant associated with recovery and changes in functioning after 3 months.

CONCLUSIONS

Different prognostic indicators were found to be associated with perceived recovery, changes in pain intensity, and changes in functioning. Future research should aim at investigating the mechanisms that can underlie these associations.

Osteoarthritis of the knee and hip and activity: a systematic international review and synthesis (OASIS)

The goal of this study was to determine which activities in four domains, daily life, exercises, sports and occupational activities, should be recommended, in favor or against, for the patient suffering from knee or hip OA.

METHODS

Scientific literature was searched in Medline, Embase and Cochrane databases for articles in French or English, reporting original data. The articles were evaluated with standardized epidemiological criteria. Seventy-two articles were retained. Recommendations were graded according to the level of scientific evidence (A high, B moderate, C clinical consensus) and were formulated for primary care.

CONCLUSIONS AND RECOMMENDATIONS

For activity of daily life (ADL), the OASIS group states with a moderate level of scientific evidence, that ADL are a risk factor for knee OA and that risk increases with intensity and duration of activity. The group concludes that healthy subjects as well as OA patients in general can pursue a high level of physical activity, provided the activity is not painful and does not predispose to trauma (grade B). Radiographic or clinical OA is not a contraindication to promoting activity in patients who have a sedentary lifestyle (grade C). For exercises and other structured activities pursued with a goal of health improvement, the group states with a high level of scientific evidence that they have a favourable effect on pain and function in the sedentary knee OA patient. The OASIS group recommends the practice of exercises and other structured activities for the sedentary patient with knee OA (grade A). Static exercises are not favored over dynamic exercises, availability, preference and tolerance being the criteria for the choice of an exercise (grade A). As results deteriorate when exercises are stopped, they should be performed at a frequency of between one and three times per week (grade B). Professional assistance can be useful in improving initial compliance and perseverance (grade B). There is no scientific argument to support halting exercise in case of an OA flare-up (grade C). For sports and recreational activity, the group states with a high degree of scientific evidence, that these activities are a risk factor for knee and hip OA and that the risk correlates with intensity and duration of exposure. The group also states, with a high degree of scientific evidence, that the risk of OA associated with sport is lesser than that associated with a history of trauma and overweight. No firm conclusion could be drawn about the possible protective role of sports such as cycling, swimming or golf. The OASIS group recommends that athletes should be informed that joint trauma is a greater risk factor than the practice of sport (Grade A). The high level athlete should be informed that the risk of OA is associated with the duration and intensity of exposure (Grade B). The OA patient can continue to engage regularly in recreational sports as long as the activity does not cause pain (Grade C). The OA patient who practices a sport at risk for joint trauma should be encouraged to change sport (Grade C). For occupational activity, the OASIS group states with a high level of scientific evidence that there is a relationship between occupational activity and OA of the knee and hip. The precise nature of biomechanical stresses leading to OA remains unclear but factors such as high loads on the joint, unnatural body position, heavy lifting, climbing and jumping may contribute to knee and hip OA. The group recommends that taking an occupational history should always be part of managing the OA patient (Grade B). In the knee or hip OA patient, work-related activity that produces or maintains pain should be avoided (Grade B). Physicians should be alerted by the early knee and hip signs and symptoms in workers exposed to stresses that are known or supposed to favour knee or hip OA (Grade C).

Factors associated with functional limitation in stair climbing in female Japanese patients with knee osteoarthritis

BACKGROUND

Osteoarthritis (OA) of the knee is a common form of arthritis, and affects quality of life. We investigated factors associated with functional limitation in stair climbing among female Japanese patients with knee OA. As weight is a known risk factor for knee OA, we focused on body weight at 40 years of age, and examined the association with present weight, past weight, and weight change.

METHODS

Subjects were 360 Japanese women aged 40-92 years who were newly diagnosed with knee OA at 3 university hospitals over a 1-year period. Factors associated with the severity of functional limitation in stair climbing were assessed by calculating odds ratios (OR) using the proportional odds model in logistic regression.

RESULTS

Weight at diagnosis showed a positive association with severe functional limitation in stair climbing; however, a negative association was observed for weight change since age 40. Further analysis indicated that the association with weight at age 40 (highest vs. lowest quartile, OR=2.84, 95% confidence interval: 1.03-7.83, trend p=0.071) is stronger than weight at diagnosis. Other significant characteristics were age (70+ vs. 40-59 years, OR=7.37), previous knee pain and/or swelling 12 years or more before diagnosis (OR=2.67), and physical work (OR=1.94). In addition, higher parity was found to be a negatively associated factor (for tripara or more, OR=0.41).

CONCLUSIONS

This study identified factors, such as heavy weight at age 40 and physical labor, which are potentially useful for preventing severe functional limitation for female knee OA patients. In addition, higher parity was associated with milder stair climbing limitation.

Risk factors for knee osteoarthritis in Japanese men: a case-control study

Risk of knee osteoarthritis (OA) was assessed in a population-based case-control study of Japanese men. The study covered three health districts in Wakayama and Osaka prefectures, Japan. Subjects were male individuals >or=45 years old diagnosed radiographically with knee OA, and who did not display any established causes of secondary OA. Controls selected randomly from the general population were individually matched to cases for age, sex, and residential district. Subjects were interviewed using structured questionnaires to determine medical history, physical activity, socio-economic factors, and occupation. Interviews were obtained from 37 cases and 37 controls. In univariate analysis, heaviest weight in the past and physical work such as factory, construction, agricultural, or fishery work as the principal occupation significantly raised the risk of male knee OA (P<0.05). Odds ratios (OR) were determined using conditional logistic regression analysis mutually adjusted for potential risk factors using the results of univariate analysis. Heaviest weight in the past (OR 6.01, 95% confidence interval (CI) 1.18-30.5, P<0.05), past knee injury (OR 6.25, 95% CI 1.13-34.5, P<0.05), and physical work as the principal occupation (OR 6.20, 95% CI 1.40-27.5, P<0.05) represented independent factors associated with knee OA after controlling for other risk factors. Physical work is associated with knee OA, demonstrating the influence of working activity on the development of OA. The present study suggests that risk factors for knee OA in men resemble those in women.

Increased body mass index is a predisposition for treatment by total hip replacement

We investigated the radiological and epidemiological data of 4,151 subjects followed up from 1976 to 2003 to determine individual risk factors for hip osteoarthritis (OA), hip pain and/or treatment by total hip replacement (THR). Pelvic radiographs recorded in 1992 were assessed for evidence of hip-joint degeneration and dysplasia. Sequential body mass index (BMI) measurements from 1976 to 1992, age, exposure to daily lifting and hip dysplasia were entered into logistic regression analyses. The prevalence of hip dysplasia ranged from 5.4% to 12.8% depending on the radiographical index used. Radiological hip OA prevalence was 1.0--2.5% in subjects <60 years of age and 4.4--5.3% in subjects >or=60 years of age. While radiological OA was significantly influenced by hip dysplasia in men and hip dysplasia and age in women, the risk of THR being performed was only influenced by BMI assessed in 1976. Hip-joint degeneration and treatment by THR do not necessarily share the same risk factors, and caution should be exercised in epidemiological studies in attributing one or the other as the end point of coxarthrosis.

Primary osteoarthritis and occupation in the Quebec national health and social survey

BACKGROUND

The scientific evidence available is consistent in linking osteoarthritis (OA) and occupation but is lacking information regarding preventable risks in the workplace.

AIMS

To explore the effect of different dimensions of physical demand in the relation between self reported OA and occupation.

METHODS

Nationwide population survey of employed and self employed adults aged 25-64.

RESULTS

Of the 11,44 workers surveyed, 3.1% (two females for one male) reported a problem with OA (any site). They reported some degree of limitations in their daily activities in a proportion that was six times higher (26.8%) than the rest of the population of the same age without OA and twice as high for absence from work in the previous year (23.8%). Of the different dimensions of risks used in the survey and controlling for age, body mass index, and smoking, "use of force with tools or machines" showed a statistically significant association with OA in males and females. In occupations significant risks of OA were identified in male unskilled labourers and skilled labourers, and in female technicians, and workers in the services sector.

CONCLUSIONS

Results of the present survey indicated that occupational stresses associated with OA may differ substantially between male and female workers and that specific risks may affect the younger workforce (25-44 years old) in some occupations, including housekeeping and other ill defined skilled and unskilled labour.

The impact of osteoarthritis: implications for research

Osteoarthritis, the clinical syndrome of joint pain and dysfunction caused by joint degeneration, affects more people than any other joint disease. There are no consistently effective methods for preventing osteoarthritis or slowing its progression, and symptomatic treatments provide limited benefit for many patients. Osteoarthritis disables about 10% of people who are older than 60 years, compromises the quality of life of more than 20 million Americans, and costs the United States economy more than $60 billion per year. The incidence of osteoarthritis rises precipitously with age; as a result, the prevalence and burden of this disorder is increasing rapidly. Study of the patterns osteoarthritis incidence and prevalence shows that it occurs frequently in the hand, foot, knee, spine and hip, but rarely in the ankle, wrist, elbow, and shoulder, and the most important universal risk factors are age, excessive joint loading, and joint injury. Analysis of the impact of osteoarthritis raises questions that include: Why does the incidence increase progressively with age? Why are some joints rarely affected? How do mechanical forces cause joint degeneration? What biologic and mechanical factors slow or accelerate the rate of joint degeneration? Answering these questions could lead to effective methods of preventing osteoarthritis and slowing its progression.

The distribution and inter-relationships of radiologic features of osteoarthrosis of the hip. A survey of 4151 subjects of the Copenhagen City Heart Study: the Osteoarthrosis Substudy

OBJECTIVE

The aims of this study were to investigate the influence of sex, age and individual physical and occupational factors on the distribution of radiographic features of hip joint osteoarthritis (OA), and to determine the inter-relationships between the primary radiographic OA discriminator of reduced joint space width (JSW), and secondary radiographic OA features.

METHOD

The study was a cross-sectional survey. Radiologic features of hip OA were recorded from standardized, standing pelvic radiographs of 3686 subjects (1397M/2289F). OA features were investigated for inter-relationships and correlations to age, sex, body mass index (BMI) and occupational exposure to repeated lifting.

RESULTS

Overall, subchondral sclerosis, cysts and osteophytes were more frequently recorded in male hip joints compared to female hip joints, while a decrease in minimum JSW by age was more pronounced and progressive in women after the fifth decade compared to men. Applying logistic regression analyses, only age was found to be significantly associated to pathologically reduced minimum JSW (cut off value set at < or =2.0 mm), and the presence of osteophytes and subchondral cysts in both sexes (P ranging from 0.00 to 0.03). Minimum JSW < or =2.0 mm was recorded in 105 male hip joints, and in 167 female hip joints. In these joints, subchondral cysts, osteophytes and sclerosis were found to be significantly inter-related to minimum JSW < or =2.0 mm according to logistic regression analysis. The presence of subchondral cysts had the highest predictive sensitivity in regard to pathologically reduced minimum JSW compared to subchondral sclerosis and osteophytes.

CONCLUSIONS

We believe that an accurate radiologic case definition of hip OA will rest on a combination of features. Only studies of the distribution of features, singularly and in combination, applied to clinically evaluated large cohorts may provide the optimum answer to the best possible clinical case definition of hip OA.