Occupational activities and osteoarthritis of the knee

A Comprehensive Summary of the Meta-Analyses and Systematic Reviews on Platelet-Rich Plasma Therapies for Knee Osteoarthritis

INTRODUCTION

Osteoarthritis (OA), including that of the knee joint, represents a significant proportion of musculoskeletal injuries in the Canadian Armed Forces (CAF) due to the frequent, high-stress physical activity for which member participation is necessary. Platelet-rich plasma (PRP) is a conservative, autologous treatment that has the potential to relieve symptoms and improve functionality of military members to decrease the impact of the disease and ultimately strengthen the CAF.

MATERIALS AND METHODS

A search of systematic reviews and meta-analyses was conducted to determine the efficacy of PRP injections in treating knee OA. The Scopus database, PubMed database, and Omni academic search tools were scoped for relevant publications. English literature, published up to and including March 2023, that investigated only clinically randomized controlled trials (RCTs) was eligible for inclusion. The results of network meta-analyses were investigated and summarized independent of reviews and non-network meta-analyses.

RESULTS

A total of 225 unique systematic reviews and meta-analyses were initially identified, of which 39 publications, including 7 network meta-analyses, adhered to the defined inclusion and exclusion criteria. PRP was found to significantly alleviate symptoms of pain based on the visual analog scale and Western Ontario and McMaster Universities Arthritis Index pain scores within the 12-month follow-up. Function, activity, sport, quality of life, and stiffness were additionally determined to generally improve to a greater extent from PRP treatment compared to controls, while adverse effects were minor and temporary. PRP placed in the top 3 in 9 reported surface under the cumulative ranking curves, while individually reported rankings of leukocyte-poor and leukocyte-rich PRP both placed in the top 4. The clinical recommendations made were generally positive, with 17 publications acknowledging the benefits of PRP, 3 supporting possible efficacy, and an additional 8 recommending that it be an option for the conservative treatment of knee OA.

CONCLUSION

The results of this review support the efficacy of PRP for relieving symptoms of pain and improving function, stiffness, and quality of life for patients experiencing knee OA within 12 months. As a result, leukocyte-poor-PRP could be considered for members of the CAF with mild to moderate knee OA (Kellgren-Lawrence grades 1-3) to slow the progression of OA and extend the military careers of CAF members. There continues to be a need for future studies to investigate the longer-term effects of PRP to verify sustained benefits at follow-up points greater than 12 months, including findings of improvement in a delayed fashion at the 3- and 6-month timeframe compared to hyaluronic acid treatment.

Only Low Patients' Expectations Are Prognostic for Dissatisfaction With Performing Work-Related Knee-Straining Activities After Total Knee Arthroplasty: A Prospective Multicenter Cohort Study

OBJECTIVE

To investigate whether preoperative expectations regarding performing work-related knee-straining activities were associated with being dissatisfied 6 months after total knee arthroplasty (TKA) among working patients, and, to identify prognostic factors for being dissatisfied with performing these work-related knee-straining activities.

DESIGN

Multicenter prospective cohort study.

SETTING

Orthopedic surgery departments of 7 hospitals in the Netherlands.

PARTICIPANTS

A consecutive sample of 175 working patients who were on the waiting list for TKA (median age 59 years, 53% women) and intended to return to work (N=175).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE(S)

Dissatisfaction with performing work-related knee-straining activities 6 months postoperative was measured using the Work Osteoarthritis or joint-Replacement Questionnaire (score range 0-100). The clinically relevant cut-off points for being satisfied and dissatisfied were ≥71 and ≤50, respectively.

RESULTS

Thirty-three patients (19%) were dissatisfied with performing work-related knee-straining activities 6 months after TKA. Patients who expected to be dissatisfied preoperative had a 5.1 times higher odds (95% CI 1.7-15.5) of being dissatisfied 6 months postoperatively compared with patients who expected to be satisfied preoperative. Regression analyses revealed that only patients' expectations were prognostic for being dissatisfied 6 months postoperatively rather than age, pain level, or having a knee-straining job.

CONCLUSIONS

Two in 10 working patients are dissatisfied with performing work-related knee-straining activities 6 months after TKA. Only preoperative patients' expectations appeared prognostic. Therefore, we should better prepare working patients with low expectations by managing their preoperative expectations and improving their performance of work-related knee-straining activities in rehabilitation.

The association between basal metabolic rate and osteoarthritis: a Mendelian randomization study

BACKGROUND

The role of the basal metabolic rate (BMR) in osteoarthritis (OA) remains unclear, as previous retrospective studies have produced inconsistent results. Therefore, we performed a Mendelian randomization (MR) study to systematically investigate the causal relationship between the BMR and OA.

METHODS

Single-nucleotide polymorphism (SNP) data related to BMR and OA were collected in a genome-wide association study. Using OA as the outcome variable and BMR as the exposure factor, SNPs with strong correlation with the BMR as the tool variable were screened. The correlation between the BMR and OA risk was evaluated using the inverse-variance weighted method, and heterogeneity and pleiotropy were evaluated using a sensitivity analysis.

RESULTS

There was a potential causal relationship between the BMR and OA risk (odds ratio [OR], 1.014; 95% confidence interval [CI], 1.008-1.020; P = 2.29e - 6). A causal relationship was also revealed between the BMR and knee OA (OR, 1.876; 95% CI, 1.677-2.098; P = 2.98e - 28) and hip OA (OR, 1.475; 95% CI, 1.290-1.686; P = 1.26e - 8). Sensitivity analysis confirmed the robustness of these results.

CONCLUSION

Here, we identified a latent causal relationship between the BMR and the risk of OA. These results suggest that the risk of OA in the hip or knee joint may be reduced by controlling the BMR.

Knee osteoarthritis: Current status and research progress in treatment (Review)

Knee osteoarthritis (KOA) is a common chronic articular disease worldwide. It is also the most common form of OA and is characterized by high morbidity and disability rates. With the gradual increase in life expectancy and ageing population, KOA not only affects the quality of life of patients, but also poses a burden on global public health. OA is a disease of unknown etiology and complex pathogenesis. It commonly affects joints subjected to greater loads and higher levels of activity. The knee joint, which is the most complex joint of the human body and bears the greatest load among all joints, is therefore most susceptible to development of OA. KOA lesions may involve articular cartilage, synovium, joint capsule and periarticular muscles, causing irreversible articular damage. Factors such as mechanical overload, inflammation, metabolism, hormonal changes and ageing serve key roles in the acceleration of KOA progression. The clinical diagnosis of KOA is primarily based on combined analysis of symptoms, signs, imaging and laboratory examination results. At present, there is no cure for KOA and the currently available therapies primarily focus on symptomatic treatment and delay of disease progression. Knee replacement surgery is typically performed in patients with advanced disease. The current study presents a review of epidemiological characteristics, risk factors, histopathological manifestations, pathogenesis, diagnosis, treatment modalities and progress in KOA research.

"It's like a nail being driven in the ankle": A qualitative study of individuals' lived experiences to inform a core domain set for ankle osteoarthritis

OBJECTIVES

Explore individuals' lived experience with ankle osteoarthritis and to identify health-related domains for ankle osteoarthritis based on the perspectives of people living with the condition, as an initial step to address the International Foot and Ankle Osteoarthritis Consortium's recommendation to develop a core domain set for ankle osteoarthritis.

METHODS

A qualitative study using semi-structured interviews was conducted. Interviews were undertaken with individuals with symptomatic ankle osteoarthritis who were aged ≥35 years. Interviews were recorded, transcribed verbatim and thematically analysed.

RESULTS

Twenty-three individuals (16 females; mean (range) age 62 (42-80) years) were interviewed. Five themes were identified: pain, often severe, is a central feature of living with ankle osteoarthritis; stiffness and swelling are key symptoms; ankle osteoarthritis induced mobility impairments compromise enjoyment in life; ankle osteoarthritis instability and balance impairments lead to concerns about falling; there are financial implications of living with ankle osteoarthritis. We propose 17 domains based on individuals' experiences.

CONCLUSION

Study findings indicate that individuals with ankle osteoarthritis live with chronic ankle pain, stiffness and swelling which affect their ability to participate in physical, and social activities, maintain an active lifestyle, and work in physical occupations. From the data, we propose 17 domains that are important to people with ankle osteoarthritis. These domains require further evaluation to ascertain their inclusion in a core domain set for ankle osteoarthritis.

Does Consulting an Occupational Medicine Specialist Decrease Time to Return to Work Among Total Knee Arthroplasty Patients? A 12-Month Prospective Multicenter Cohort Study

PURPOSE

The aim of this study is to investigate whether total knee arthroplasty (TKA) patients who consulted an occupational medicine specialist (OMS) within 3 months after surgery, return to work (RTW) earlier than patients who did not consult an OMS.

METHODS

A multi-center prospective cohort study was performed among working TKA patients, aged 18 to 65 years and intending to RTW. Time to RTW was analyzed using Kaplan Meier and Mann Whitney U (MWU), and multiple linear regression analysis was used to adjust for effect modification and confounding.

RESULTS

One hundred and eighty-two (182) patients were included with a median age of 59 years [IQR 54-62], including 95 women (52%). Patients who consulted an OMS were less often self-employed but did not differ on other patient and work-related characteristics. TKA patients who consulted an OMS returned to work later than those who did not (median 78 versus 62 days, MWU p < 0.01). The effect of consulting an OMS on time to RTW was modified by patients' expectations in linear regression analysis (p = 0.05). A median decrease in time of 24 days was found in TKA patients with preoperative high expectations not consulting an OMS (p = 0.03), not in patients with low expectations.

CONCLUSIONS

Consulting an OMS within 3 months after surgery did not result in a decrease in time to RTW in TKA patients. TKA patients with high expectations did RTW earlier without consulting an OMS. Intervention studies on how OMSs can positively influence a timely RTW, incorporating patients' preoperative expectations, are needed.

Prediction of progression rate and fate of osteoarthritis: Comparison of machine learning algorithms

Appropriate prediction models can assist healthcare systems in delaying or reversing osteoarthritis (OA) progression. We aimed to identify a reliable algorithm for predicting the progression rate and fate of OA based on patient-specific information. From May 2003 to 2019, 83,280 knees were collected. Age, sex, body mass index, bone mineral density, physical demands for occupation, comorbidities, and initial Kellgren-Lawrence (K-L) grade were used as variables for the prediction models. The prediction targets were divided into dichotomous groups for even distribution. We compared the performances of logistic regression (LR), random forest (RF), and extreme gradient boost (XGB) algorithms. Each algorithm had the best precision when the model used all variables. XGB showed the best results in accuracy, recall, F1 score, specificity, and error rates (progression rate/fate of OA: 0.710/0.877, 0.542/0.637, 0.637/0.758, 0.859/0.981, and 0.290/0.123, respectively). The feature importance of RF and XGB had the same order up to the top six for each prediction target. Age and initial K-L grade had the highest feature importance in RF and XGB for the progression rate and fate of OA, respectively. The XGB and RF machine learning algorithms showed better performance than conventional LR in predicting the progression rate and fate of OA. The best performance was obtained when all variables were combined using the XGB algorithm. For each algorithm, the initial K-L grade and physical demand for occupation were the greatest contributors with superior feature importance compared with the others.

Do Individualized Patient-Specific Situations Predict the Progression Rate and Fate of Knee Osteoarthritis? Prediction of Knee Osteoarthritis

Factors affecting the progression rate and fate of osteoarthritis need to be analyzed when considering patient-specific situation. This study aimed to identify the rate of remarkable progression and fate of primary knee osteoarthritis based on patient-specific situations. Between May 2003 and May 2019, 83,280 patients with knee pain were recruited for this study from the clinical data warehouse. Finally, 2492 knees with pain that were followed up for more than one year were analyzed. For analyzing affecting factors, patient-specific information was categorized and classified as demographic, radiologic, social, comorbidity disorders, and surgical intervention data. The degree of contribution of factors to the progression rate and the fate of osteoarthritis was analyzed. Bone mineral density (BMD), Kellgren-Lawrence (K-L) grade, and physical occupational demands were major contributors to the progression rate of osteoarthritis. Hypertension, initial K-L grade, and physical occupational demands were major contributors to the outcome of osteoarthritis. The progression rate and fate of osteoarthritis were mostly affected by the initial K-L grade and physical occupational demands. Patients who underwent surgical intervention for less than five years had the highest proportion of initial K-L grade 2 (49.0%) and occupations with high physical demand (41.3%). In identifying several contributing factors, the initial K-L grade and physical occupational demands were the most important factors. BMD and hypertension were also major contributors to the progression and fate of osteoarthritis, and the degree of contribution was lower compared to the two major factors.

Unsupervised machine-learning algorithms for the identification of clinical phenotypes in the osteoarthritis initiative database

OBJECTIVES

Osteoarthritis (OA) is a complex disease comprising diverse underlying patho-mechanisms. To enable the development of effective therapies, segmentation of the heterogenous patient population is critical. This study aimed at identifying such patient clusters using two different machine learning algorithms.

METHODS

Using the progression and incident cohorts of the Osteoarthritis Initiative (OAI) dataset, deep embedded clustering (DEC) and multiple factor analysis with clustering (MFAC) approaches, including 157 input-variables at baseline, were employed to differentiate specific patient profiles.

RESULTS

DEC resulted in 5 and MFAC in 3 distinct patient phenotypes. Both identified a "comorbid" cluster with higher body mass index (BMI), relevant burden of comorbidity and low levels of physical activity. Both methods also identified a younger and physically more active cluster and an elderly cluster with functional limitations, but low disease impact. The additional two clusters identified with DEC were subgroups of the young/physically active and the elderly/physically inactive clusters. Overall pain trajectories over 9 years were stable, only the numeric rating scale (NRS) for pain showed distinct increase, while physical activity decreased in all clusters. Clusters showed different (though non-significant) trajectories of joint space changes over the follow-up period of 8 years.

CONCLUSION

Two different clustering approaches yielded similar patient allocations primarily separating complex "comorbid" patients from healthier subjects, the latter divided in young/physically active vs elderly/physically inactive subjects. The observed association to clinical (pain/physical activity) and structural progression could be helpful for early trial design as strategy to enrich for patients who may specifically benefit from disease-modifying treatments.

Computational biomechanics of human knee joint in stair ascent: Muscle-ligament-contact forces and comparison with level walking

About a third of knee joint disorders originate from the patellofemoral (PF) site that makes stair ascent a difficult activity for patients. A detailed finite element model of the knee joint is coupled to a lower extremity musculoskeletal model to simulate the stance phase of stair ascent. It is driven by the mean of measurements on the hip-knee-ankle moments-angles as well as ground reaction forces reported in healthy individuals. Predicted muscle activities compare well to the recorded electromyography data. Peak forces in quadriceps (3.87 BW, body weight, at 20% instance in our 607 N subject), medial hamstrings (0.77 BW at 20%), and gastrocnemii (1.21 BW at 80%) are estimated. Due to much greater flexion angles-moments in the first half of stance, large PF contact forces (peak of 3.1 BW at 20% stance) and stresses (peak of 4.83 MPa at 20% stance) are estimated that exceed their peaks in level walking by fourfold and twofold, respectively. Compared with level walking, ACL forces diminish in the first half of stance but substantially increase later in the second half (peak of 0.76 BW at 75% stance). Under nearly similar contact forces at 20% of stance, the contact stress on the tibiofemoral (TF) medial plateau reaches a peak (9.68 MPa) twice that on the PF joint suggesting the vulnerability of both joints. Compared with walking, stair ascent increases peak ACL force and both peak TF and PF contact stresses. Reductions in the knee flexion moment and/or angle appear as a viable strategy to mitigate internal loads and pain.

Environmental Risk Factors for Osteoarthritis: The Impact on Individuals with Knee Joint Injury

Osteoarthritis is a debilitating chronic condition involving joint degeneration, impacting over 300 million people worldwide. This places a high social and economic burden on society. The knee is the most common joint impacted by osteoarthritis. A common cause of osteoarthritis is traumatic joint injury, specifically injury to the anterior cruciate ligament. The purpose of this review is to detail the non-modifiable and modifiable risk factors for osteoarthritis with particular focus on individuals after anterior cruciate ligament injury. After reading this, health care providers will better comprehend the wide variety of factors linked to osteoarthritis.

Orang Asli Health and Lifeways Project (OA HeLP): a cross-sectional cohort study protocol

INTRODUCTION

Non-communicable disease (NCD) risk is influenced by environmental factors that are highly variable worldwide, yet prior research has focused mainly on high-income countries where most people are exposed to relatively homogeneous and static environments. Understanding the scope and complexity of environmental influences on NCD risk around the globe requires more data from people living in diverse and changing environments. Our project will investigate the prevalence and environmental causes of NCDs among the indigenous peoples of Peninsular Malaysia, known collectively as the Orang Asli, who are currently undergoing varying degrees of lifestyle and sociocultural changes that are predicted to increase vulnerability to NCDs, particularly metabolic disorders and musculoskeletal degenerative diseases.

METHODS AND ANALYSIS

Biospecimen sampling and screening for a suite of NCDs (eg, cardiovascular disease, type II diabetes, osteoarthritis and osteoporosis), combined with detailed ethnographic work to assess key lifestyle and sociocultural variables (eg, diet, physical activity and wealth), will take place in Orang Asli communities spanning a gradient from remote, traditional villages to acculturated, market-integrated urban areas. Analyses will first test for relationships between environmental variables, NCD risk factors and NCD occurrence to investigate how environmental changes are affecting NCD susceptibility among the Orang Asli. Second, we will examine potential molecular and physiological mechanisms (eg, epigenetics and systemic inflammation) that mediate environmental effects on health. Third, we will identify intrinsic (eg, age and sex) and extrinsic (eg, early-life experiences) factors that predispose certain people to NCDs in the face of environmental change to better understand which Orang Asli are at greatest risk of NCDs.

ETHICS AND DISSEMINATION

Approval was obtained from multiple ethical review boards including the Malaysian Ministry of Health. This study follows established principles for ethical biomedical research among vulnerable indigenous communities, including fostering collaboration, building cultural competency, enhancing transparency, supporting capacity building and disseminating research findings.

Water carrying in hills of Nepal–associations with women’s musculoskeletal disorders, uterine prolapse, and spontaneous abortions

More than a third of women in Nepal have to carry water from source to home to satisfy their families’ daily needs. A cross-sectional study was carried out in a hilly area in Nepal to assess water-carrying practices and their association with women’s health. Quantitative interviews were conducted with 1001 women of reproductive age and were complemented with health surveys carried out by health professionals and structured observations of water carrying. Multivariate mixed logistic regression models were used to assess the associations between water-carrying-related risk factors and health issues for women. Around 46% of women faced considerably increased to excessive physical stress due to water carrying during the dry season. Women suffered from a disproportionately high prevalence of back pain (61%), with about 18% of this pain being horrible to excruciating; pain in the knees (34%); uterine prolapse (11.3%); and at least one spontaneous abortion (9%). The risk category of water carrying was significantly associated with uterine prolapse (OR = 1.44, 95%CI = 1.12–1.85, p = 0.031) and pain in the hips (OR = 1.69, 95%CI = 1.27–2.26, p<0.001). Receiving help with water carrying during pregnancy and during the first three months after delivery was associated with reduced odds ratios for uterine prolapse (OR = 0.10, 95% CI = 0.01–0.87, p = 0.037), and strong back pain (OR = 0.32, 95% CI = 0.12–0.87, p = 0.026). Improvements to water supply infrastructure and the promotion of social support for carrying water during pregnancy and after delivery are recommended to reduce water-carrying-related health risks.

Dusty trades and associated rheumatoid arthritis in a population-based study in the coal mining counties of Appalachia

OBJECTIVES

We previously showed increased coal mining-associated risk of rheumatoid arthritis (RA). Using additional survey data, we sought to delineate this risk further.

METHODS

We used data from two cross-sectional, random-digit-dial, population-based surveys (males;≥50 years) in selected counties in the Appalachian region of the inland, mid-Atlantic USA with elevated pneumoconiosis mortality. Surveys ascertained age, smoking, coal mining and non-coal silica exposure jobs. In a subset, we surveyed ergonomic exposures, scored by intensity. We queried diagnosis of RA, corticosteroid use, and, in a subset, use of disease modifying antirheumatic drugs (DMARDs). Multivariable logistic regression modelled RA risk (defined by glucocorticoid or DMARDs use) associated with coal mining employment, other silica exposure, smoking status, and age and ergonomic exposures.

RESULTS

We analysed data for 2981 survey respondents (mean age 66.6 years; 15% current, 44% ex-smokers). The prevalence of glucocorticoid-treated and DMARD-treated RA was 11% and 4%, respectively. Glucocorticoid-treated RA was associated with coal mining (OR 3.5; 95% CI 2.5 to 4.9) and non-coal mining silica exposure (OR 3.2; 95% CI 2.4 to 4.4). For DMARD-treated RA, the odds associated with coal mining and other silica remained elevated: OR 2.3 (95% CI 1.18, 4.5) and OR 2.7 (95% CI 1.51, 5.0), respectively. In the same model, the highest intensity ergonomic exposure also was associated with increased odds of RA (OR 4.3; 95% CI 1.96 to 9.6).

CONCLUSIONS

We observed a strong association between coal mining and other silica-exposing dusty trades and RA. Clinicians and insurers should consider occupational histories in the aetiology of RA.

Work-related factors of knee osteoarthritis in Korean farmers: a cross-sectional study

Background

Several studies have reported a high prevalence of osteoarthritis (OA) of the knee among agricultural workers. We investigated work-related factors that increase the risk of knee OA among Korean farmers.

Methods

Data were extracted from the Jeonnam Center for Farmer's Safety and Health survey, conducted between 2013 and 2015. The sample included 489 farmers (man 240, woman 249). We defined knee OA as radiographic knee OA (≥ Kellgren-Lawrence grade 2) with symptoms (≥ Western Ontario and McMaster Universities Osteoarthritis, Korean version score 29.5). We considered covariates such as cumulative squatting working time (CSWT), cumulative heavy lifting working time (CLWT), body mass index (BMI), and history of knee injury. Odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were calculated for knee OA and adjusted for relevant covariates.

Results

The results of multivariate logistic regression analysis indicated that knee OA was correlated by factors such as sex, age, BMI, history of knee injury, CSWT, and CLWT. Particularly, CSWT > 20,000 hours (OR: 2.83; 95% CI: 1.35-5.92; reference < 10,000 hours) and CLWT > 5,000 hours (OR: 2.62; 95% CI: 1.14-6.06; reference < 2,000 hours) were associated with an increased risk of knee OA after adjustment for covariates.

Conclusions

Squatting posture and heavy lifting associated with farm work might increase the risk of knee OA among Korean farmers.

Monitoring work-related physical activity and estimating lower-limb loading: a proof-of-concept study

BACKGROUND

Physical activity (PA) is important to general health and knee osteoarthritis (OA). Excessive workplace PA is an established risk factor for knee OA however, appropriate methods of measurement are unclear. There is a need to examine and assess the utility of new methods of measuring workplace PA and estimating knee load prior to application to large-scale, knee OA cohorts. Our aims, therefore, were to monitor workplace PA and estimate lower-limb loading across different occupations in health participants.

METHODS

Twenty-four healthy adults, currently working full-time in a single occupation (≥ 35 h/week) and free of musculoskeletal disease, comorbidity and had no history of lower-limb injury/surgery (past 12-months) were recruited across New South Wales (Australia). A convenience sample was recruited with occupations assigned to levels of workload; sedentary, light manual and heavy manual. Metrics of workplace PA including tasks performed (i.e., sitting), step-count and lower-limb loading were monitored over 10 working days using a daily survey, smartwatch, and a smartphone.

RESULTS

Participants of light manual occupations had the greatest between-person variations in mean lower-limb load (from 2 to 59 kg*m/s3). Lower-limb load for most participants of the light manual group was similar to a single participant in heavy manual work (30 kg*m/s3) and was at least three times greater than the sedentary group (2 kg*m/s3). The trends of workplace PA over working hours were largely consistent, per individual, but rare events of extreme loads were observed across all participants (up to 760 kg*m/s3).

CONCLUSIONS

There are large interpersonal variations in metrics of workplace PA, particularly among light and heavy manual occupations. Our estimates of lower-limb loading were largely consistent with pre-conceived levels of physical demand. We present a new approach to monitoring PA and estimating lower-limb loading, which could be applied to future occupational studies of knee OA.

How does occupational physical activity influence health? An umbrella review of 23 health outcomes across 158 observational studies

OBJECTIVE

Physical activity (PA) has substantial benefits across a range of health outcomes. There is uncertainty about the PA-specific health effects, and in particular, the occupational domain. In this umbrella review, we synthesised available evidence on the associations between occupational PA (OPA) and health-related outcomes (including cancer, all-cause mortality and cardiovascular disease). This work informed the development of WHO's guidelines on PA and sedentary behaviour (2020).

DESIGN

Umbrella review of systematic reviews.

DATA SOURCE

We performed a literature search in PubMed, Web of Science, Embase, CINAHL and Sportdiscuss from database inception to 2 December 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included systematic reviews if they contained a quantitative assessment of OPA and its relationship with at least one health-related outcome.

RESULTS

We summarised the evidence of 17 reviews covering 23 unique health-related outcomes. We graded most evidence as low or very low, or moderate quality. We found health benefits for those engaging in high versus low OPA for multiple cancer outcomes (including colon and prostate), ischaemic stroke, coronary heart disease and mental health (ie, mental well-being and life satisfaction). High OPA was associated with unfavourable health outcomes for all-cause mortality in men, mental ill health (ie, depression and anxiety), osteoarthritis, and sleep quality and duration.

CONCLUSIONS

We found favourable associations for most health-related outcomes with high OPA levels, but we also found some evidence for unfavourable associations due to high OPA levels. At this point, there is a need for better quality evidence to provide a unequivocal statement on the health effects of OPA.

Comparison of two different models of rehabilitation programs following total knee replacement operations

Background

Total knee replacement operation (TKR) is the treatment of choice in severe knee osteoarthritis (OA). Rehabilitation post-TKR is still not well studied. The aim of this study was to compare between the high-intensity (HI) rehabilitation program and the low-intensity (LI) rehabilitation program following TKR.

Results

At 1 month following the TKR operations, significant improvements were found in the first group compared to the second group in all the measured parameters except for the knee range of motion (ROM). At 3 and 12 months follow-up periods, there were statistically significant differences between both groups in all the evaluated parameters except for the numeric pain rating scale and the knee ROM.

Conclusions

Both high-intensity and low-intensity rehabilitation programs are effective; however, HI program had superior functional gain and patient-reported outcomes compared to the LI program. Moreover, HI group has a long-term functional gain.

Factors related to femoral bowing among Korean female farmers: a cross-sectional study

Background

Female farmers have a high prevalence of knee osteoarthritis (KOA) in South Korea. Femoral bowing has been reported to be related to KOA by increasing load on the mechanical axis. This study aimed to investigate factors related to femoral bowing in Korean female farmers.

Methods

We analyzed the legs of 264 female farmers registered with the Korea farmers' knee cohort of Jeonnam Center for Farmers' Safety and Health. A structured questionnaire was used to determine sociodemographic variables, agricultural career, cumulative squatting working time (CSWT), and cumulative heavy lifting working time. Femoral bone density was measured and Kellgren-Lawrence (KL) grades were obtained from the knee radiographs. Mechanical axis angle (MAA), femoral bowing angle (FBA), anatomical lateral distal femoral angle (aLDFA), anatomical medial proximal tibial angle (aMPTA), and condylar-plateau angle (CPA) were measured. We examined the relationship between the FBA and related factors by using multiple linear regression.

Results

The proportion of individuals with radiographic KOA (≥ KL grade 2) in this study was 37.9%. As KL grades increased, MAA, FBA, and CPA increased, whereas aLDFA and aMPTA decreased. FBA increased with age. Multiple linear regression analyses using FBA as a dependent variable showed relationship with higher age, lower height, higher BMI, lower bone mineral density, longer CSWT, and longer agricultural careers.

Conclusions

The results of this study suggest that external factors related to agricultural work in female farmers was associated with femoral bowing, in addition to internal factors such as age, bone density, height, and obesity.

Occupation and risk of knee osteoarthritis and knee replacement: A longitudinal, multiple-cohort study

OBJECTIVES

To examine the effect of occupation on knee osteoarthritis (OA) and total knee replacement (TKR) in working-aged adults.

METHODS

We used longitudinal data from the Chingford, Osteoarthritis Initiative (OAI) and Multicentre Osteoarthritis (MOST) studies. Participants with musculoskeletal disorders and/or a history of knee-related surgery were excluded. Participants were followed for up to 19-years (Chingford), 96-months (OAI) and 60-months (MOST) for incident outcomes including radiographic knee OA (RKOA), symptomatic RKOA and TKR. In those with baseline RKOA, progression was defined as the time from RKOA incidence to primary TKR. Occupational job categories and work-place physical activities were assigned to levels of workload. Logistic regression was used to examine the relationship between workload and incident outcomes with survival analyses used to assess progression (reference group: sedentary occupations).

RESULTS

Heavy manual occupations were associated with a 2-fold increased risk (OR: 2.07, 95% CI 1.03 to 4.15) of incident RKOA in the OAI only. Men working in heavy manual occupations in MOST (2.7, 95% CI 1.17 to 6.26) and light manual occupations in OAI (2.00, 95% CI 1.09 to 3.68) had a 2-fold increased risk of incident RKOA. No association was observed among women. Increasing workload was associated with an increased risk of symptomatic RKOA in the OAI and MOST. Light work may be associated with a decreased risk of incident TKR and disease progression.

CONCLUSION

Heavy manual work carries an increased risk of incident knee OA; particularly among men. Workload may influence the occurrence of TKR and disease progression.

Association of bone mineral density with the development of knee osteoarthritis in men and women: a cross-sectional study using the fourth and fifth Korea National Health and Nutrition Examination Surveys

Bone mineral density (BMD) and osteoarthritis (OA) were correlated but the relationship was varied according to sex. An association between lumbar spine and femur neck BMDs and OA showed a positive relation in women, while lumbar spine and pelvis BMDs in men were associated with OA with a negative relation.

PURPOSE

The purpose of this study was to evaluate the association of BMD in various body parts in conjunction with the presence or severity of radiographic knee osteoarthritis (KOA) in relation to sex.

METHODS

This study was a cross-sectional analysis using Korea National Health and Nutrition Examination Surveys. KOA was graded using the Kellgren-Lawrence (KL) grading system. Radiographic KOA was defined as a KL grade 2 or higher. The associations between KOA and BMD in certain body parts (femur, pelvis, lumbar, lower leg, and whole-body) were assessed. BMD was measured using dual-energy X-ray absorptiometry. The BMD of each body part was divided into quartiles and the relationship between KOA and BMD was examined according to sex.

RESULTS

BMD did not show a significant tendency according to KL grade in either sex. In men, the severity of KL grade have a statistically significant relationship with total femur (R² = 0.303, p < 0.05), femur neck (R² = 0.257, p < 0.05), lumbar (R² = 0.137, p < 0.05), and pelvis BMD (R² = 0.185, p < 0.05). In women, total femur (R² = 0.466, p < 0.05), lumbar (R² = 0.316, p < 0.05), pelvis (R² = 0.343, p < 0.05), and lower leg BMD (R² = 0.133, p < 0.05) were associated with the severity of KL grade. When the BMD was divided into quartiles, lumbar (p < 0.05) and pelvis BMD (p < 0.05) in men had statistically significant association with knee OA as BMD decreased. In women, femur neck (p < 0.05) and lumbar BMD (p < 0.05) were significantly associated with knee OA as BMD increased.

CONCLUSION

The relationship between BMD and OA severity varied according to sex. In women, there was a positive association between femur neck and lumbar BMD and OA, while BMD of the lumbar and pelvis in men was negatively correlated with OA.

LEVEL OF EVIDENCE

Cohort study, III.

[Osteoarthrosis in the clinic of internal and occupational diseases: differential diagnostic aspects]

Osteoarthritis is a common pathology, which indicates the great medical and social significance of this disease. The article discusses the issues of pathogenesis, risk factors and diagnosis of professional and professionally caused osteoarthritis: the age of onset of the disease, the specifics of work, the localization of joint damage. Differential diagnosis issues are discussed.

Occupational Activities: Factors That Tip the Balance From Bone Accrual to Bone Loss

Bone adaptation to persistent overloading can be counteracted by superimposed inflammatory and loading-induced damage that can tip the balance from bone accrual to loss.

Supplemental digital content is available in the text.

It is commonly assumed that beneficial adaptations in bone occur with vigorous exercise, yet any adaptive re/modeling in bone undergoing persistent overloading can be counteracted by superimposed inflammatory, compressive, and tensile loading–induced damage responses above thresholds of tissue fatigue failure and repair. This leads to a tenuous balance between achieving bone accrual and loss.

Intraarticular injection of bone marrow-derived mesenchymal stem cells enhances regeneration in knee osteoarthritis

PURPOSE

This review aimed to evaluate the efficacy of intra-articular injections of bone marrow derived mesenchymal stem cells (BM-MSCs) for the treatment of knee osteoarthritis (KOA).

METHODS

This narrative review evaluates recent English language clinical data and published research articles between 2014 and 2019. Key word search strings of ((("bone marrow-derived mesenchymal stem cell" OR "bone marrow mesenchymal stromal cell" OR "bone marrow stromal cell")) AND ("osteoarthritis" OR "knee osteoarthritis")) AND ("human" OR "clinical"))) AND "intra-articular injection" were used to identify relevant articles using PMC, Cochrane Library, Web Of Science and Scopus databases.

RESULTS

Pre-clinical studies have demonstrated successful, safe and encouraging results for articular cartilage repair and regeneration. This is concluded to be due to the multilineage differential potential, immunosuppressive and self-renewal capabilities of BM-MSCs, which have shown to augment pain and improve functional outcomes. Subsequently, clinical applications of intra-articular injections of BM-MSCs are steadily increasing, with most studies demonstrating a decrease in poor cartilage index, improvements in pain, function and Quality of Life (QoL); with moderate-to-high level evidence regarding safety for therapeutic administration. However, low confidence in clinical efficacy remains due to a plethora of heterogenous methodologies utilised, resulting in challenging study comparisons. A moderate number of cells (40 × 10⁶) were identified as most likely to achieve optimal responses in individuals with grade ≥ 2 KOA. Likewise, significant improvements were reported when using lower (24 × 10⁶) and higher (100 × 10⁶) cell numbers, although adverse effects including persistent pain and swelling were a consequence.

CONCLUSION

Overall, the benefits of intra-articular injections of BM-MSCs were deemed to outweigh the adverse effects; thus, this treatment be considered as a future therapy strategy. To realise this, long-term large-scale randomised clinical trials are required to enable improved interpretations, to determine the validity of efficacy in future studies.

LEVEL OF EVIDENCE

IV.

Risk factors for development of lower limb osteoarthritis in physically demanding occupations: A narrative umbrella review

Objectives

Osteoarthritis (OA) is a common disorder which affects the joints. As relationships between occupational factors and lower limb OA have been widely studied in systematic reviews, the aim of this umbrella review was to synthesize their key findings in the risk factors for development of lower limb OA.

Methods

A systematic search was conducted using the databases PUBMED, Cumulative Index of Nursing and Allied Health Literature, and Elton B Stevens Company to identify reviews examining associations between lower limb OA and occupational tasks. These reviews were rated for their methodological quality before key data were extracted and synthesized.

Results

Sixteen reviews were found, seven pertained to the knee, four to the hip, two to a variety of joints, and three to both the hip and knee. One was deemed to be of high methodological quality, one of critically low methodological quality, and the others of moderate methodological quality. The reviews found moderate to good evidence for heavy occupational lifting to be associated with an increased risk of OA at the knee and the hip. Kneeling, squatting, and climbing, previous injuries to joints, being overweight and obese were also predictive of lower limb OA.

Conclusion

Occupations which involve heavy physical workloads increase the risk of developing lower limb OA. Heavy lifting, squatting, knee bending, kneeling, and climbing may all increase the risk of developing OA in both the knees and hips. Efforts to reduce exposure to these tasks, reducing joint injuries, optimizing bodyweight may reduce the risks of lower limb OA for occupations which are physically demanding.

Knee osteoarthritis among airport baggage handlers: A prospective cohort study

BACKGROUND

Knee osteoarthritis is a common and often disabling disorder, which has been related to knee-straining work. However, exposure response relations are uncertain and there are few prospective studies. We studied prospectively if incident knee osteoarthritis is associated with cumulative exposure as an airport baggage handler, lifting on average 5000 kg/d.

METHODS

The study is based on the Copenhagen Airport Cohort, a historical cohort of male baggage handlers and a reference group of unskilled men from the greater Copenhagen area, followed from 1990 to 2012. Cumulative years of employment as a baggage handler was based on information from company employment and union registers. Outcome was first hospital admission with a discharge diagnosis of knee osteoarthritis and/or knee replacement, ascertained from the Danish National Patient Register.

RESULTS

The cohort contained 3442 baggage handlers and 65 511 workers in the reference group. The unadjusted incidence rate ratio (IRR) of knee osteoarthritis increased steeply with cumulative years as a baggage handler. Although the exposure-response pattern became weaker and statistically nonsignificant (P ≈ .10) when adjusting for age, the risk of knee osteoarthritis was still increased in baggage handlers at the highest exposure level. Additional analyses showed that the association between age and osteoarthritis was stronger for baggage handlers (IRR = 2.09; 95% CI: 1.68-2.60) than for referents (IRR = 1.58; 95% CI: 1.53-1.63), indicating that knee osteoarthritis occurred at a younger age among baggage handlers than in the reference group.

CONCLUSIONS

The results of this prospective cohort study support that long-term heavy lifting increases the risk of knee osteoarthritis.

Pain, Physical Function, Radiographic Features, and Quality of Life in Knee Osteoarthritis Agricultural Workers Living in Rural Population

Background

The aim of this study was to analyse the relationship between the clinical manifestations, disease severity based on radiography images, functional activity level, and quality of life in patients with knee osteoarthritis in a rural population living in Serbian enclaves in Kosovo, as well as to determine the correlation between the WOMAC and the EQ-5D questionnaire in this population.

Method

The cross-sectional study was conducted at the Internal Medicine Clinic, Clinical Hospital Center Pristina-Gracanica, located in Laplje Selo from February to December 2013. One hundred patients with confirmed (American College of Rheumatology criteria) knee osteoarthritis completed the EQ-5D and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaires, rated pain on a visual analogue scale (VAS), and underwent knee radiographic examinations.

Result

Most patients were obese with moderate radiographic changes according to the Kellgeren–Lawrence scale and suffered from very severe pain according to the VAS scale. The duration of disease significantly correlated with the WOMAC scores, VAS score, and all of the scores on the EQ-5D, except for mobility. The age of participants showed a similar correlation with the same variables. The patients with higher Kellgren–Lawrence scores (3-4) were significantly older, with a significantly higher body mass index (BMI) and longer duration of disease than patients with lower scores (1-2). Significantly higher VAS, pain/discomfort EQ-5D, and WOMAC pain and function scores were also recorded among patients with more significant radiological changes. The correlations between WOMAC and EQ-5D were satisfactory.

Conclusion

The severity of clinical manifestations and radiographic area changes may affect functional ability and the quality of life in knee OA patients living in rural areas, which requires adequate treatment and physical therapy.

Three Out of Ten Working Patients Expect No Clinical Improvement of Their Ability to Perform Work-Related Knee-Demanding Activities After Total Knee Arthroplasty: A Multicenter Study

Purpose Three out of ten patients do not return to work after total knee arthroplasty (TKA). Patient expectations are suggested to play a key role. What are patients' expectations regarding the ability to perform work-related knee-demanding activities 6 months after TKA compared to their preoperative status? Methods A multi-center cross-sectional study was performed among 292 working patients listed for TKA. The Work Osteoarthritis or joint-Replacement Questionnaire (WORQ, range 0-100, minimal important difference 13) was used to assess the preoperatively experienced and expected ability to perform work-related knee-demanding activities 6 months postoperatively. Differences between the preoperative and expected WORQ scores were tested and the most difficult knee-demanding work-related activities were described. Results Two hundred thirty-six working patients (81%) completed the questionnaire. Patients' expected WORQ score (Median = 75, IQR 60-86) was significantly (p < 0.01) higher than their preoperative WORQ score (Median = 44, IQR 35-56). A clinical improvement in ability to perform work-related knee-demanding activities was expected by 72% of the patients, while 28% of the patients expected no clinical improvement or even worse ability to perform work-related knee-demanding activities 6 months after TKA. Of the patients, 34% expected severe difficulty in kneeling, 30% in crouching and 17% in clambering 6 months after TKA. Conclusions Most patients have high expectations, especially regarding activities involving deep knee flexion. Remarkably, three out of ten patients expect no clinical improvement or even a worse ability to perform work-related knee-demanding activities 6 months postoperatively compared to their preoperative status. Therefore, addressing patients expectations seems useful in order to assure realistic expectations regarding work activities.

Prevalence of Arthritis and Rheumatoid Arthritis in Coal Mining Counties of the United States

OBJECTIVE

Exposure to inhaled mineral dust, in particular silica, is associated with increased odds of rheumatoid arthritis (RA) and other autoimmune diseases. We studied the association of RA with work-related coal and silica exposure in the Appalachian region of the US.

METHODS

We carried out a random-digit dialed telephone survey in selected counties in Appalachia that had elevated coal workers' pneumoconiosis mortality. Our study cohort included men ages ≥50 with any employment history, and we assessed exposure to coal mining employment, other work-related dust, and ergonomic factors. We ascertained self-reported physician diagnosis of any arthritis and of RA with glucocorticoid treatment. We used multivariable logistic regression analysis to estimate the odds ratios (ORs) and associated population attributable fraction (PAF) estimates.

RESULTS

Among the 973 men who met study entry criteria (mean ± SD ages 66 ± 10 years; 54% ever smokers), 266 (27%) reported coal mining work and 189 (19%) reported other work-related silica exposure. There were 517 men (53%), who reported any arthritis and 112 (12%) whose disease met the study definition of RA. Adjusting for covariates, coal mining was associated with elevated odds of RA (OR 3.6 [95% confidence interval (95% CI) 2.1-6.2]), which accounted for a PAF of 33% (95% CI 26-40%) of the men studied. For any arthritis, the coal mining-associated OR was 2.3 (95% CI 1.6-3.2), with an associated PAF of 20% (95% CI 14-25%).

CONCLUSION

In this population of older males living in a coal mining region, we estimated that 20% of arthritis and 33% of RA may be attributable to coal mining work.

Effect of Osteoarthritis on Work Participation and Loss of Working Life-years

OBJECTIVE

To examine to what extent disabling osteoarthritis (OA), leading to a prolonged sickness absence (SA), interferes with work participation and shortens working life-years.

METHODS

A total of 4704 wage earners aged 30 to 59 years, whose SA due to OA started in 2006, were followed until October 31, 2014. Kaplan-Meier analysis was used to plot sustained (at least 28 consecutive days) return-to-work curves. The associations of potential determinants with early exit from paid employment were examined applying Cox proportional hazards regression analysis. Years expected to be spent in different work participation statuses until statutory retirement age were estimated based on daily work participation statuses using adapted Sullivan method.

RESULTS

Persons with knee OA showed the fastest, and persons with hip OA the slowest, sustained return to work. Although most participants typically were at work during the first year of followup, a considerable proportion was permanently retired. Male sex, older age, low education, long initial SA, and having not returned to work sustainably, as well as receiving vocational rehabilitation, predicted early exit from paid employment during the followup. Overall, only 45-53% of potential working life-years were estimated to be spent at work, being highest for the oldest age group.

CONCLUSION

Our study showed a considerable effect of OA on work participation and working life duration. Clinicians should avoid prescription of long SA or temporary work disability due to OA without a clear treatment or return-to-work plan.

To what extent do education and physical work load factors explain occupational differences in disability retirement due to knee OA? A nationwide register-based study in Finland

OBJECTIVES

To examine the association of education and physical work load factors on the occupational differences in disability retirement due to knee osteoarthritis (OA).

DESIGN

Longitudinal study.

SETTING

Linkage of several nationwide registers and a job exposure matrix in Finland.

PARTICIPANTS

A total of 1 135 654 Finns aged 30-60 years in gainful employment were followed from 2005 to 2013 for full disability retirement due to knee OA.

PRIMARY AND SECONDARY OUTCOME MEASURES

We calculated age-adjusted incidence rates and examined the association of occupation, education and physical work load factors with disability retirement using competing risk regression model. Disability retirement due to other causes than knee OA, old-age retirement and death were treated as competing risk.

RESULTS

A total of 6117 persons had disability retirement due to knee OA. Women had a higher age-adjusted incidence rate than men (72 vs 60 per 100 000 person-years, respectively). In men, a very high risk of disability retirement was found among construction workers, electricians and plumbers (HR 16.6, 95% CI 12.5 to 22.2), service workers (HR 12.7, 95% CI 9.2 to 17.4) and in women among building caretakers, cleaners, assistant nurses and kitchen workers (HR 15.5, 95% CI 11.7 to 20.6), as compared with professionals. The observed occupational differences were largely explained by educational level and noticeably mediated by physical work load factors in both genders.

CONCLUSION

Our observational study suggests that the risk of disability retirement among manual workers is strongly attributed to the physically heavy work.

Contribution of central and peripheral risk factors to prevalence, incidence and progression of knee pain: a community-based cohort study

AIM

To explore risk factors that may influence knee pain (KP) through central or peripheral mechanisms.

METHODS

A questionnaire-based prospective community cohort study with KP defined as pain in or around a knee on most days for at least a month. Baseline prevalence, and one year incidence and progression (KP worsening) were examined. Central (e.g., Pain Catastrophizing Scale (PCS)) and peripheral (e.g., significant injury) risk factors were examined. Adjusted odds ratio (OR) and 95% confidence interval (CI) were calculated using logistic regression. Proportional risk contribution (PRC) was estimated using receiver-operator-characteristic (ROC) analysis.

RESULTS

Of 9506 baseline participants, 4288 (45%) had KP (men 1826; women, 2462). KP incidence was 12% (men 11%, women 13%), and KP progression 19% (men 16%, women 21%) at one year. While both central and peripheral factors contributed to prevalence, central factors contributed more to progression, and peripheral factors more to incidence of KP. For example, although PCS (OR 2.06, 95% CI 1.88-2.25) and injury (5.62, 4.92-6.42) associated with KP prevalence, PCS associated with progression (2.27, 1.83-2.83) but not incidence (1.14, 0.86-1.52), whereas injury more strongly associated with incidence (69.27, 24.15-198.7) than progression (2.52, 1.48-4.30). The PRC of central and peripheral factors were 19% and 23% for prevalence, 14% and 29% for incidence, and 29% and 5% for progression, respectively.

CONCLUSIONS

Both central and peripheral risk factors influence KP but relative contributions may differ in terms of development (mainly peripheral) and progression (mainly central). Further study of such relative contributions may inform primary and secondary prevention strategies.

Arthritis diagnosis and symptoms are positively associated with specific physical job exposures in lower- and middle-income countries: cross-sectional results from the World Health Organization's Study on global AGEing and adult health (SAGE)

BACKGROUND

In higher income countries, work-related squatting and heavy lifting have been associated with increased arthritis risk. Here, we address the paucity of data regarding associations between arthritis and work-related physical stressors in lower- and middle-income countries.

METHODS

Data were extracted from the Study on global AGEing and adult health (SAGE) Wave 1 (2007-10) for adults (aged ≥50 years) from Ghana, India, Russia and South Africa for whom detailed occupation data was available (n = 21,389; 49.2% women). Arthritis cases were identified using a symptom-defined algorithm (current) and self-reported doctor-diagnosis (lifetime). A sex-specific Job Exposure Matrix was used to classify work-related stressors: heavy physical work, kneeling/squatting, heavy lifting, arm elevation and awkward trunk posture. Using the International Standard Classification of Occupations, we linked SAGE and the Job Exposure Matrix. Logistic regression was used to investigate associations between arthritis and work-related stressors, adjusting for age (10 year age groupings), potential socioeconomic-related confounders, and body mass index. Excess exposure risk due to two-way interactions with other risk factors were explored.

RESULTS

Doctor-diagnosed arthritis was associated with heavy physical work (adjusted odds ratios [OR] 1.12, 95%CI 1.01-1.23), awkward trunk posture (adjusted OR 1.23, 95%CI 1.12-1.36), kneeling or squatting (adjusted OR 1.25, 95%CI 1.12-1.38), and arm elevation (adjusted OR 1.66, 95%CI 1.37-2.00). Symptom-based arthritis was associated with kneeling or squatting (adjusted OR 1.27, 95%CI 1.08-1.50), heavy lifting (adjusted OR 1.33, 95%CI 1.11-1.58), and arm elevation (adjusted OR 2.16, 95%CI 1.63-2.86). Two-way interactions suggested excess arthritis risk existed for higher body mass index, and higher income or education.

CONCLUSIONS

Minimization of occupational health risk factors is common practice in higher income countries: attention should now be directed toward reducing work-related arthritis burden in lower- and middle-income countries.

Prevalence, duration and risk factors for appendicular osteoarthritis in a UK dog population under primary veterinary care

Osteoarthritis is the most common joint disease diagnosed in veterinary medicine and poses considerable challenges to canine welfare. This study aimed to investigate prevalence, duration and risk factors of appendicular osteoarthritis in dogs under primary veterinary care in the UK. The VetCompass^TM programme collects clinical data on dogs attending UK primary-care veterinary practices. The study included all VetCompass^TM dogs under veterinary care during 2013. Candidate osteoarthritis cases were identified using multiple search strategies. A random subset was manually evaluated against a case definition. Of 455,557 study dogs, 16,437 candidate osteoarthritis cases were identified; 6104 (37%) were manually checked and 4196 (69% of sample) were confirmed as cases. Additional data on demography, clinical signs, duration and management were extracted for confirmed cases. Estimated annual period prevalence (accounting for subsampling) of appendicular osteoarthritis was 2.5% (CI₉₅: 2.4-2.5%) equating to around 200,000 UK affected dogs annually. Risk factors associated with osteoarthritis diagnosis included breed (e.g. Labrador, Golden Retriever), being insured, being neutered, of higher bodyweight and being older than eight years. Duration calculation trials suggest osteoarthritis affects 11.4% of affected individuals' lifespan, providing further evidence for substantial impact of osteoarthritis on canine welfare at the individual and population level.

Prevalence of knee pain, radiographic osteoarthritis and arthroplasty in retired professional footballers compared with men in the general population: a cross-sectional study

Objectives

To determine the prevalence of knee pain, radiographic knee osteoarthritis (RKOA), total knee replacement (TKR) and associated risk factors in male ex-professional footballers compared with men in the general population (comparison group).

Methods

1207 male ex-footballers and 4085 men in the general population in the UK were assessed by postal questionnaire. Current knee pain was defined as pain in or around the knees on most days of the previous month. Presence and severity of RKOA were assessed on standardised radiographs using the Nottingham Line Drawing Atlas (NLDA) in a subsample of 470 ex-footballers and 491 men in the comparison group. The adjusted risk ratio (aRR) and adjusted risk difference (aRD) with 95% CI in ex-footballers compared with the general population were calculated using the marginal model in Stata.

Results

Ex-footballers were more likely than the comparison group to have current knee pain (aRR 1.91, 95% CI 1.77 to 2.06), RKOA (aRR 2.21, 95% CI 1.92 to 2.54) and TKR (aRR 3.61, 95% CI 2.90 to 4.50). Ex-footballers were also more likely to present with chondrocalcinosis (aRR 3.41, 95% CI 2.44 to 4.77). Prevalence of knee pain and RKOA were higher in ex-footballers at all ages. However, even after adjustment for significant knee injury and other risk factors, there was more than a doubling of risk of these outcomes in footballers.

Conclusions

The prevalence of all knee osteoarthritis outcomes (knee pain, RKOA and TKR) were two to three times higher in male ex-footballers compared with men in the general population group. Knee injury is the main attributable risk factor. Even after adjustment for recognised risk factors, knee osteoarthritis appear to be an occupational hazard of professional football.

Occupational Exposure to Knee Loading and the Risk of Osteoarthritis of the Knee: A Systematic Review and a Dose-Response Meta-Analysis

BACKGROUND

Osteoarthritis of the knee is considered to be related to knee straining activities at work. The objective of this review is to assess the exposure dose-response relation between kneeling or squatting, lifting, and climbing stairs at work, and knee osteoarthritis.

METHODS

We included cohort and case-control studies. For each study that reported enough data, we calculated the odds ratio (OR) per 5,000 hours of cumulative kneeling and per 100,000 kg of cumulative lifting. We pooled these incremental ORs in a random effects meta-analysis.

RESULTS

We included 15 studies (2 cohort and 13 case-control studies) of which nine assessed risks in more than two exposure categories. We considered all but one study at high risk of bias. The incremental OR per 5,000 hours of kneeling was 1.26 (95% confidence interval 1.17-1.35, 5 studies, moderate quality evidence) for a log-linear exposure dose-response model. For lifting, there was no exposure dose-response per 100,000 kg of lifetime lifting (OR 1.00, 95% confidence interval 1.00-1.01). For climbing, an exposure dose-response could not be calculated.

CONCLUSION

There is moderate quality evidence that longer cumulative exposure to kneeling or squatting at work leads to a higher risk of osteoarthritis of the knee. For other exposure, there was no exposure dose-response or there were insufficient data to establish this. More reliable exposure measurements would increase the quality of the evidence.

Osteoarthritis, labour division, and occupational specialization of the Late Shang China - insights from Yinxu (ca. 1250 - 1046 B.C.)

This research investigates the prevalence of human osteoarthritis at Yinxu, the last capital of the Late Shang dynasty (ca. 1250–1046 B.C.), to gain insights about lifeways of early urban populations in ancient China. A total of 167 skeletal remains from two sites (Xiaomintun and Xin’anzhuang) were analyzed to examine osteoarthritis at eight appendicular joints and through three spinal osseous indicators. High osteoarthritis frequencies were found in the remains with males showing significantly higher osteoarthritis on the upper body (compared to that of the females). This distinctive pattern becomes more obvious for males from Xiaomintun. Furthermore, Xiaomintun people showed significantly higher osteoarthritis in both sexes than those from Xin’anzhuang. Higher upper body osteoarthritis is speculated to be caused by repetitive lifting and carrying heavy-weight objects, disproportionately adding more stress and thus more osseous changes to the upper than the lower body. Such lifting-carrying could be derived from intensified physical activities in general and specialized occupations in particular. Higher osteoarthritis in males may reveal a gendered division of labour, with higher osteoarthritis in Xiaomintun strongly indicating an occupational difference between the two sites. The latter speculation can be supported by the recovery of substantially more bronze-casting artifacts in Xiaomintun. It is also intriguing that relatively higher osteoarthritis was noticed in Xiaomintun females, which seems to suggest that those women might have also participated in bronze-casting activities as a “family business.” Such a family-involved occupation, if it existed, may have contributed to establishment of occupation-oriented neighborhoods as proposed by many Shang archaeologists.

Physical activity and osteoarthritis: a consensus study to harmonise self-reporting methods of physical activity across international cohorts

Physical activity (PA) is increasingly recognised as an important factor within studies of osteoarthritis (OA). However, subjective methods used to assess PA are highly variable and have not been developed for use within studies of OA, which creates difficulties when comparing and interpreting PA data in OA research. The aim of this study was, therefore, to gain expert agreement on the appropriate methods to harmonise PA data among existing population cohorts to enable the investigation of the association of PA and OA. The definition of PA in an OA context and methods of harmonization were established via an international expert consensus meeting and modified Delphi exercise using a geographically diverse committee selected on the basis of individual expertise in physical activity, exercise medicine, and OA. Agreement was met for all aims of study: (1) The use of Metabolic Equivalent of Task (MET) minutes per week (MET-min/week) as a method for harmonising PA variables among cohorts; (2) The determination of methods for treating missing components of MET-min/week calculation; a value will be produced from comparable activities within a representative cohort; (3) Exclusion of the domain of occupation from total MET-min/week; (4) The need for a specific measure of joint loading of an activity in addition to intensity and time, in studies of diseases, such as OA. This study has developed a systematic method to classify and harmonise PA in existing OA cohorts. It also provides minimum requirements for future studies intending to include subjective PA measures.

Stand up: comparison of two electrical screed levelling machines to reduce the work demands for the knees and low back among floor layers

Electrical screed levelling machines are developed to reduce kneeling and trunk flexion of sand-cement-bound screed floor layers. An observational intervention study among 10 floor layers was performed to assess the differences between a self-propelled and a manually moved machine. The outcome measures were work demands, production time, perceived load, discomfort and applicability. Compared to the self-propelled machine, the duration of kneeling (∆13 min; p = 0.003) and trunk flexion (∆12 min; p < 0.001) was shorter using the manually moved machine, and the duration of pushing and pulling increased (∆39 min; p < 0.001). No significant or relevant differences were found for production time, perceived load and discomfort. Nine out of ten floor layers found the manually moved machine applicable and three out of ten found the self-propelled machine applicable. When compared with the traditional manner of floor laying, both electrical machines reduced the exposure towards kneeling and trunk flexion. Practitioner Summary: Electrical machines may help to reduce high physical work demands on floor layers. A manually moved machine is better applicable for the installation of screed floors in residences with smaller floor areas. A self-propelled machine is better applicable on large floor areas with a minimum width of 4 m.

Effect of Ginger Supplementation on Proinflammatory Cytokines in Older Patients with Osteoarthritis: Outcomes of a Randomized Controlled Clinical Trial

There is limited evidence that ginger powder consumption can relieve pain and inflammation due to specific anti-inflammatory phytochemical constitutents. This study investigates the effect of ginger supplementation on proinflammatory factors in participants (n = 120) of a randomized double-blind placebo-controlled 3-month clinical trial investigating knee osteoarthritis. Patients were randomly assigned to one of two groups: the ginger group (GG) or the placebo group (PG). Administered daily for 3 months, participants in the GG intervention received capsules containing 500 mg of ginger powder, while PG participants received capsules filled with 500 mg starch. Serum samples collected at baseline and 3 months were analyzed for serum levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). At baseline, proinflammatory cytokine concentrations did not differ by group. However, at 3 months, both cytokines decreased in the GG relative to the PG. The results of this study indicate that ginger supplementation may have a promising benefits for knee osteoarthritis and may, therefore, may warrant further study.

Incidence and prevalence of total joint replacements due to osteoarthritis in the elderly: risk factors and factors associated with late life prevalence in the AGES-Reykjavik Study

Background

Total joint replacements (TJRs) should be considered as one of few definite endpoints in osteoarthritis research. We analyzed factors associated with late-life prevalence and risk factors for incidence of TJRs due to osteoarthritis in a population based cohort.

Methods

After exclusion of inflammatory arthritis and fractures as causes of TJR, 5170 participants in the AGES-Reykjavik Study (mean age (SD) 76.4(6), 58 % females) were included for osteoarthritis studies. Three thousand one hundred thirty-three of them had a follow-up visit 5 years later.

Results

The prevalence of having at least one joint replacement operation due to OA was 13.6 % and the yearly incidence was 1.4 %/year during the five-year follow-up. Factors positively associated with late life prevalence of TJR included BMI, hand OA severity, female gender, finger length ratio and spine BMD. Risk factors for TJRs in the incidence group were symptoms at initial visit, prior TJR in the contralateral joint and BMI. Much stronger associations were seen for TKR than for THR with discriminatory analysis showing an AUC 0.71 for late life prevalence and 0.84 for the incidence.

Conclusions

This study illustrates the importance of the different information expressed by late life prevalence vs. incidence on the factors associated with severe osteoarthritis of the knee and hip. The observation that prior TJR is a risk factor for subsequent TJR in the contralateral joint has not been described previously. The high power predictions for TKR suggest that a predictive model may be feasible, particularly if it can be extended by the addition of further predictive variables, perhaps through genetic, biomarker or imaging data.

Patient-reported factors influencing return to work after joint replacement

BACKGROUND

An increasing number of patients in the working population are undergoing total hip and knee replacement for osteoarthritis and the timing and success of return to work (RTW) is becoming increasingly important as a measure of success for these patients. There is limited understanding of the patient variables that determine the ability to RTW.

AIMS

To explore the factors influencing RTW following hip and knee replacement from the patient's perspective.

METHODS

A cross-sectional population-based postal survey carried out with patients of working age after hip and knee replacement surgery in a UK teaching hospital. Free text comments were collected regarding the experiences of patients returning to work following hip and knee replacement. Qualitative thematic analysis was undertaken to identify the factors influencing RTW from the patient's perspective.

RESULTS

From the patients' perspective three key factors were identified that influenced RTW. Patients reported an improved physical and psychological performance at work after surgery in comparison to pre-operative functioning, although there was a lack of informed advice regarding RTW after surgery. Workplace support and adaptation of the job role enhanced the experience of RTW.

CONCLUSIONS

Return to work is influenced by a combination of patient, clinician and occupational factors. The relationship between each of these needs to be explored in greater depth through further qualitative work to gain a wider understanding of the variables influencing patients' RTW following hip and knee replacement.

Health and Employment after Fifty (HEAF): a new prospective cohort study

BACKGROUND

Demographic trends in developed countries have prompted governmental policies aimed at extending working lives. However, working beyond the traditional retirement age may not be feasible for those with major health problems of ageing, and depending on occupational and personal circumstances, might be either good or bad for health. To address these uncertainties, we have initiated a new longitudinal study.

METHODS/DESIGN

We recruited some 8000 adults aged 50-64 years from 24 British general practices contributing to the Clinical Practice Research Datalink (CPRD). Participants have completed questionnaires about their work and home circumstances at baseline, and will do so regularly over follow-up, initially for a 5-year period. With their permission, we will access their primary care health records via the CPRD. The inter-relation of changes in employment (with reasons) and changes in health (e.g., major new illnesses, new treatments, mortality) will be examined.

DISCUSSION

CPRD linkage allows cost-effective frequent capture of detailed objective health data with which to examine the impact of health on work at older ages and of work on health. Findings will inform government policy and also the design of work for older people and the measures needed to support employment in later life, especially for those with health limitations.

Ageing, musculoskeletal health and work

Changing demographics mean that many patients with soft tissue rheumatism, osteoarthritis, inflammatory arthritis, large joint prostheses and age-related co-morbidities are seeking to work beyond the traditional retirement age. In this chapter, we review the evidence on musculoskeletal health and work at older ages. We conclude that musculoskeletal problems are common in older workers and have a substantial impact on their work capacity. Factors that influence their job retention are described, together with approaches that may extend working life. Many gaps in evidence were found, notably on the health risks and benefits of continued work in affected patients and on which interventions work best. The roles of physicians and managers are also considered.