Occupational risk factors for osteoarthritis of the knee: a meta-analysis

Incidence of knee and hip joint replacement associated with cumulative exposure to physical factors at work

BACKGROUND

Knee osteoarthritis (OA) has been quite consistently associated with high physical workload and specific physical factors at work, while for hip OA, fewer studies are available, which still indicate possible associations with heavy lifting and physical workload. The objective of the study was to assess the association between exposure to workplace physical factors and incidence of knee and hip arthroplasty, as markers of severe OA in these joints.

METHODS

The study population was composed of employees 25-60 years who participated in the Turin 2011 census. For each job held since 1995, exposure to physical factors was assigned to individuals in the cohort through a Job-Exposure Matrix constructed from the Italian O*NET database. Using Poisson regression models, the incidence of knee and hip arthroplasty for OA, identified through hospitalizations from 2012 to 2018, was examined in relation to cumulative exposure to 7 different physical hazards and a composite indicator of physical workload constructed from 17 physical factors (Ergo-Index).

RESULTS

The risk of knee OA was significantly increased in the highest cumulative exposure quartile of physical workload (incidence rate ratio = 1.98, 95% confidence interval: 1.24-3.16) and of all single hazards examined, compared to the lowest quartile, with significant trends in risk with increasing exposure. In contrast, no association was found with hip OA, whose relative risks were close to or below one in all higher-exposure quartiles of physical workload and of each single hazard.

CONCLUSIONS

Our results indicate that exposure to physical hazards at work increases the likelihood of developing knee OA, but not hip OA.

EULAR recommendations for the non-pharmacological core management of hip and knee osteoarthritis: 2023 update

INTRODUCTION

Hip and knee osteoarthritis (OA) are increasingly common with a significant impact on individuals and society. Non-pharmacological treatments are considered essential to reduce pain and improve function and quality of life. EULAR recommendations for the non-pharmacological core management of hip and knee OA were published in 2013. Given the large number of subsequent studies, an update is needed.

METHODS

The Standardised Operating Procedures for EULAR recommendations were followed. A multidisciplinary Task Force with 25 members representing 14 European countries was established. The Task Force agreed on an updated search strategy of 11 research questions. The systematic literature review encompassed dates from 1 January 2012 to 27 May 2022. Retrieved evidence was discussed, updated recommendations were formulated, and research and educational agendas were developed.

RESULTS

The revised recommendations include two overarching principles and eight evidence-based recommendations including (1) an individualised, multicomponent management plan; (2) information, education and self-management; (3) exercise with adequate tailoring of dosage and progression; (4) mode of exercise delivery; (5) maintenance of healthy weight and weight loss; (6) footwear, walking aids and assistive devices; (7) work-related advice and (8) behaviour change techniques to improve lifestyle. The mean level of agreement on the recommendations ranged between 9.2 and 9.8 (0-10 scale, 10=total agreement). The research agenda highlighted areas related to these interventions including adherence, uptake and impact on work.

CONCLUSIONS

The 2023 updated recommendations were formulated based on research evidence and expert opinion to guide the optimal management of hip and knee OA.

Access to Total Knee Arthroplasty for Military Insured Patients

Background

Rigorous training may lead to increased rates of knee osteoarthritis and arthroplasties in military service members. Given the large numbers of arthritis and the increasing need for total joint replacements, access to appropriate care can be difficult for this population based on insurance restrictions. The aim of this study was to evaluate access to total knee arthroplasty for TRICARE patients in contracted civilian medical facilities.

Methods

Orthopedic surgeons contracted to perform total knee replacements in the state of Florida were identified via TRICARE's website. Investigators used a secret shopper methodology with a standardized script to request an appointment for their family member for a total knee arthroplasty using either TRICARE Select or BlueCross preferred provider organization. The appointment acceptance rates, wait times, call duration, and accuracy of the physician listing were collected.

Results

A total of 228 offices that perform total knee arthroplasties in Florida were successfully contacted. Overall, 43.1% of the clinics had an inaccurate online listing, and 207 (91%) were able to schedule an appointment with TRICARE, compared to 93% for BlueCross Blue Shield (P = .06). The average wait for TRICARE patients was 24 days and 18 days for BlueCross (P < .01). Call times for TRICARE patients averaged 7.2 minutes, compared to 5.2 minutes for BlueCross (P < .01).

Conclusions

TRICARE patients encountered longer waiting periods and inaccurate provider listings when accessing orthopedic care. Our results suggest a disparity in healthcare access for patients using TRICARE, which may result in negative health outcomes from receiving delayed care.

Stepping Forward: A Scoping Review of Physical Activity in Osteoarthritis

Physical activity (PA) is recommended to mitigate the symptoms of osteoarthritis (OA); however, this modality remains an unfamiliar construct for many patients and clinicians. Moreover, there can be confusion over the nuanced differences in terminology, such as exercise, sedentary behavior, and moderate intensity. The purpose of this scoping review is to provide a basic overview of PA including terminology, summarize the importance of PA for adults with OA, and discuss current gaps in the literature. Broadly, PA is defined as any energy expenditure from skeletal muscle above a resting level, and exercise is considered a type of PA that is planned, structured, and repetitive. Robust literature shows that PA has a modest protective effect on pain, functional limitation, and disability for OA, in addition to positive effects on a broad range of outcomes from mood and affect to mortality and morbidity in the general population. We provide recommendations for which measurement instruments can be used to record PA, both from a clinical and research perspective, as well as which metrics to employ for summarizing daily activity.

Risk of symptomatic osteoarthritis associated with exposure to ergonomic factors at work in a nationwide Italian survey

OBJECTIVE

The risk of developing osteoarthritis (OA) has been reported to increase with exposure to various ergonomic factors at work, although this finding is still debated in the literature. Aim of this study was to assess the association between prevalence of symptomatic OA and exposure to workplace ergonomic factors assigned through a job-exposures matrix (JEM).

METHODS

The study population was composed of 24,604 persons of 40-69 years who participated in the National Health Survey 2013 and were employed at that occasion. Exposure to ergonomic factors was assigned to the study population through a JEM constructed from the Italian O*NET database, consisting of 17 physical factors, which were summed and averaged by job title (796 jobs) to obtain a combined exposure index. The outcome was self-reported OA characterized by moderate or severe limitations in daily activities. The relationship between OA prevalence and the combined exposure index in quartiles was examined using robust Poisson regression models adjusted for socio-demographics and potential confounders.

RESULTS

In the analysis adjusted for age and gender, the risk of OA was increased by approximately 20-30% in the second and third quartiles, and by 80% in the highest exposure quartile, compared to the least exposed, with a risk attenuation by approximately 15-20% controlling for other significant covariates.

CONCLUSION

Our results support a causal role of exposure to physical factors at work in the development of OA. As OA is associated with a great burden of disability, any effort should be made to reduce workers' exposure to ergonomic factors.

Do Knee-Straining Activities Influence the Subchondral Bone Microarchitecture and Accelerate Knee Osteoarthritis Progression?

BACKGROUND

Knee overload was detrimental to knee osteoarthritis subjects. We aim to analyze the association between the subchondral bone microarchitecture sclerosis and typical knee-straining activities.

METHODS

The frequency of experiencing squatting, kneeling, lifting, and climbing of 481 knee osteoarthritis subjects was investigated. Subchondral bone microarchitecture (bone volume fraction, trabecular thickness, trabecular separation, and trabecular number) was measured by the fast imaging with steady-state free precession magnetic resonance imaging applying trabecular sequencing, at baseline and 12-mo follow-up. Logistic regression was conducted to investigate the relationship between microarchitecture change and each knee-straining activity, adjusted by age, sex, weight, and Kellgren-Lawrence grade. All data were from the Osteoarthritis Initiative.

RESULTS

Long kneeling was associated with increased bone volume fraction (adjusted odds ratio = 1.16, confidence interval = 1.01-1.33) and trabecular number (adjusted odds ratio = 1.16, confidence interval = 1.02-1.33). Long squatting was associated with a lower risk of increased trabecular separation (adjusted odds ratio = 0.84, confidence interval = 0.71-0.98) and a higher risk of increased trabecular thickness (adjusted odds ratio = 1.29, confidence interval = 1.06-1.55). Long squatting also increased the medial compartment joint width narrowing (-0.21 in squatting group vs -0.03 in no squatting group, P < 0.05).

CONCLUSIONS

Knee osteoarthritis patients should avoid long squatting and kneeling, and subchondral bone microarchitecture possesses excellent potential as a monitoring indicator in subjects who kneel or squat for long.

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.

Senior Military Rank Is Associated With Higher Rates of Return to Running and Unrestricted Activity Among Military Servicemembers After Surgical Repair of Patellar Tendon Rupture at 1-Year Follow-up

Purpose

To evaluate 1-year outcomes in active-duty servicemembers who underwent patellar tendon rupture repair and to identify baseline variables associated with return to activity.

Methods

We performed a retrospective review of all active-duty servicemembers undergoing primary patellar tendon rupture repair between 2009 and 2014. All patients had a minimum 12-month follow-up. Demographic variables were recorded, as well as ability to return to impact activities and remain on active-duty status. Rates of recurrent rupture and revision surgery were identified. Univariate analysis was performed to assess relations between outcomes and baseline variables.

Results

A total of 123 patients met the inclusion criteria (average age, 33.5 ± 6.6 years; 99% male patients) with a mean follow-up period of 4.3 ± 2.2 years. Whereas 67.4% of patients returned to running at an average of 8.3 months from index surgery, only 42.4% of patients resumed unrestricted occupational function. Higher rates of return to running were observed among patients with senior military rank (P = .046). Senior military rank was also associated with a higher rate of return to unrestricted active-duty status (P = .006). Logistic regression analysis showed an association between postoperative pain (odds ratio [OR], 0.684; 95% confidence interval [CI], 0.56-0.84; P < .001) and return to running, between postoperative pain (OR, 0.77; 95% CI, 0.60-0.98; P = .033) and return to active duty, and between rank (OR, 2.06; 95% CI, 1.04-4.07; P = .037) and return to active duty. Patients who sustained injuries during deployment had a higher rate of recurrent rupture (26.1% vs 9.3%, P = .028).

Conclusions

At 1-year follow-up, approximately two-thirds of military servicemembers undergoing primary patellar tendon repair had returned to running after surgery, whereas fewer than one-half returned to full military duty. Younger age and more senior military rank were associated with higher rates of return to running. Additionally, servicemembers of higher rank, particularly officers, had statistically higher rates of return to unrestricted activity.

Level of Evidence

Level IV, therapeutic case series.

Clinical Effect of Catgut Embedding plus Warm Needle Moxibustion on Improving Inflammation and Quality of Life of Knee Osteoarthritis Patients

Objective

To clarify influence of catgut embedding plus warm needle moxibustion on improving inflammation and quality of life of knee osteoarthritis patients.

Materials and Methods

The data of 120 patients with knee osteoarthritis admitted to our hospital from June 2018 to June 2021 were used for retrospective analysis. Patients were divided into control group and observation group in a random manner, with 60 cases each. The control group was orally administrated with one diclofenac sodium sustained-release tablet (100 mg) once a day, for 8 courses with 7 days for each course. The observation group underwent catgut embedding plus warm needle moxibustion.

Results

The Western Ontario and McMaster Universities Arthritis Index and gonitis Lequesne scores in two groups were decreased after treatment and were lower in observation group than control group (P < 0.05). Quality of life scores presented elevation after treatment and were higher in observation group than control group (P < 0.05). Curative efficacy presented no difference between two groups (P > 0.05), while clinical cure rate was higher in observation group than control group (X2 = 8.257, P = 0.006).

Conclusion

Warm needle moxibustion plus functional exercise can effectively improve clinical symptoms of knee osteoarthritis patients, and improve their knee joint function and inflammatory response.

Classification of kneeling and squatting in workers wearing protective equipment: development and validation of a rule-based model using wireless triaxial accelerometers

Several professions in industries, such as petroleum, manufacturing, construction, mining, and forestry require prolonged work tasks in awkward postures, increasing workers' risks for musculoskeletal pain and injury. Therefore, we developed and validated a rule-based model for classifying unilateral and bilateral kneeling and squatting based on 15 individuals wearing personal protective equipment and using three wireless triaxial accelerometers. The model provided both high sensitivity and specificity for classifying kneeling (0.98; 0.98) and squatting (0.96; 0.91). Hence, this model has the potential to contribute to increased knowledge of physical work demands and exposure thresholds in working populations with strict occupational safety regulations. Practitioner summary: Our results indicate that this rule-based model can be applied in a human-factors perspective enabling high-quality quantitative information in the classification of occupational kneeling and squatting, known risk factors for musculoskeletal pain, and sick leave. This study is adapted for working populations wearing personal protective equipment and aimed for long-term measurements in the workplace.

Cohort profile: the Halland osteoarthritis (HALLOA) cohort-from knee pain to osteoarthritis: a longitudinal observational study in Sweden

PURPOSE

The overall objective in this study is to investigate the early development of radiographic knee osteoarthritis (OA) and its association with hand or/and knee OA, metabolic diseases, biomarkers, chronic pain, physical function and daily physical activity types.

PARTICIPANTS

The Halland osteoarthritis (HALLOA) cohort is a longitudinal cohort study that includes individuals with knee pain in the southwest of Sweden. Enrolment took place from 2017 to 2019. The inclusion criteria were current knee pain, with no former known radiographic knee OA and no cruciate ligament rupture or rheumatological disorder. The participants were recruited: (1) when seeking care for knee pain in primary healthcare or (2) by advertisements in local newspapers. There are 306 individuals included in the study, mean age (SD) 51.7 (8.7) years and 69% are women. The baseline and follow-ups include clinical tests, radiographical examinations, blood samples, metabolic measures, pain pressure thresholds, tests of physical functions, daily physical activity types and patient-reported outcomes.

FINDINGS TO DATE

There were associations between metabolic factors and radiographic knee OA, even in those with normal body mass index at baseline. In addition, clinical hand OA was positively associated with fasting plasma glucose. We also found that modifiable factors as increased visceral fat and total body fat were associated with increased pain sensitivity among individuals with knee pain.

FUTURE PLANS

By studying possible pathophysiological mechanisms of OA over time, we aim to provide new insights on OA progression, identify usable preventive measures helping the clinicians in the management of the disease and improve health for the patients. It is also important to study the development of chronic pain in OA, to get tools to identify individuals at risk and to be able to offer them treatment.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT04928170).

Recreational Physical Activity and Risk of Incident Knee Osteoarthritis: An International Meta-Analysis of Individual Participant-Level Data

OBJECTIVE

The effect of physical activity on the risk of developing knee osteoarthritis (OA) is unclear. We undertook this study to examine the relationship between recreational physical activity and incident knee OA outcomes using comparable physical activity and OA definitions.

METHODS

Data were acquired from 6 global, community-based cohorts of participants with and those without knee OA. Eligible participants had no evidence of knee OA or rheumatoid arthritis at baseline. Participants were followed up for 5-12 years for incident outcomes including the following: 1) radiographic knee OA (Kellgren-Lawrence [K/L] grade ≥2), 2) painful radiographic knee OA (radiographic OA with knee pain), and 3) OA-related knee pain. Self-reported recreational physical activity included sports and walking/cycling activities and was quantified at baseline as metabolic equivalents of task (METs) in days per week. Risk ratios (RRs) were calculated and pooled using individual participant data meta-analysis. Secondary analysis assessed the association between physical activity, defined as time (hours per week) spent in recreational physical activity and incident knee OA outcomes.

RESULTS

Based on a total of 5,065 participants, pooled RR estimates for the association of MET days per week with painful radiographic OA (RR 1.02 [95% confidence interval (95% CI) 0.93-1.12]), radiographic OA (RR 1.00 [95% CI 0.94-1.07]), and OA-related knee pain (RR 1.00 [95% CI 0.96-1.04]) were not significant. Similarly, the analysis of hours per week spent in physical activity also showed no significant associations with all outcomes.

CONCLUSION

Our findings suggest that whole-body, physiologic energy expenditure during recreational activities and time spent in physical activity were not associated with incident knee OA outcomes.

Work intensity and quality of life can be restored following double-level osteotomy in varus knee osteoarthritis

PURPOSE

The purpose of this study was to assess changes in health-related quality of life (HRQL) and work intensity following double-level knee osteotomy (DLO). It was hypothesized that postoperative HRQL would be comparable to that of the general population and that work intensity can be restored in the short term.

METHODS

Twenty-four patients (28 varus knees; mechanical tibiofemoral angle: -11.0 ± 3.0° (-6.0 to -17.0), age: 49.1 ± 9.5 (31-65) years) who underwent DLO were included. The duration the patients were unable to work was evaluated. HRQL was measured with the SF-36 questionnaire, which consists of a physical (PCS) and mental component summary score (MCS). The pre- to postoperative changes in the PCS and MCS were analysed. The PCS and MCS were also compared to those of the general population, who has a reference score value of 50 points. The work intensity measured with the REFA classification and the Tegner activity scale were assessed preoperatively and at the final postoperative follow-up examination (18.0 ± 10.0 (5-43) months).

RESULTS

The duration that the patients were unable to work was 12.2 ± 4.4 (6-20) weeks. The PCS improved from 32.1 ± 11.3 (14.5-53.3) preoperatively to 54.6 ± 8.5 (25.2-63.7) (p < 0.001) at the final follow-up, and the MCS improved from 53.9 ± 11.1 (17.1-67.7) to 57.2 ± 3.1 (47.3-61.7) (n.s). The preoperative PCS was significantly lower than the reference score of the general population (p < 0.001), whereas the preoperative MCS was similar between the two groups (n.s.). At follow-up, no significant differences were observed between the PCS and the MCS of the patient group and those of the general population. Five patients who were unable to work prior to surgery due to knee symptoms returned to work with moderate (four patients) or even very heavy (one patient) workloads. The Tegner activity scale increased significantly from a median of 2.0 (0.0-5.0) to 4.0 (2.0-7.0) (p < 0.001).

CONCLUSION

Our results demonstrate an improvement in quality of life and return to working activity following DLO in the short term. The HRQL can be improved by DLO in patients with varus knee osteoarthritis to the level of the general population. These results can assist surgeons in discussing realistic expectations when considering patients for DLO.

LEVEL OF EVIDENCE

Study type: therapeutic, IV.

Risk of revision arthroplasty surgery after exposure to physically demanding occupational or leisure activities: A systematic review

INTRODUCTION

Lower limb arthroplasty is successful at relieving symptoms associated with joint failure. However, physically-demanding activities can cause primary osteoarthritis and accordingly such exposure post-operatively might increase the risk of prosthetic failure. Therefore, we systematically reviewed the literature to investigate whether there was any evidence of increased risk of revision arthroplasty after exposure to intensive, physically-demanding activities at work or during leisure-time.

METHODS

We searched Medline, Embase and Scopus databases (1985-July 2021) for original studies including primary lower limb arthroplasty recipients that gathered information on physically-demanding occupational and/or leisure activities and rates of revision arthroplasty. Methodological assessment was performed independently by two assessors using SIGN, AQUILA and STROBE. The protocol was registered in PROSPERO [CRD42017067728].

RESULTS

Thirteen eligible studies were identified: 9 (4,432 participants) after hip arthroplasty and 4 (7,137participants) after knee arthroplasty. Narrative synthesis was performed due to considerable heterogeneity in quantifying exposures. We found limited evidence that post-operative activities (work or leisure) did not increase the risk of knee revision and could even be protective. We found insufficient high-quality evidence to indicate that exposure to physically-demanding occupations increased the risk of hip revision although "heavy work", agricultural work and, in women, health services work, may be implicated. We found conflicting evidence about risk of revision hip arthroplasty associated with either leisure-time or total physical activities (occupational or leisure-time).

CONCLUSION

There is currently a limited evidence base to address this important question. There is weak evidence that the risk of revision hip arthroplasty may be increased by exposure to physically-demanding occupational activities but insufficient evidence about the impact on knee revision and about exposure to leisure-time activities after both procedures. More evidence is urgently needed to advise lower limb arthroplasty recipients, particularly people expecting to return to jobs in some sectors (e.g., construction, agriculture, military).

Long Non-Coding RNA PVT1 and Its Target miRNA-146a as Potential Prognostic Biomarkers in Rheumatoid Arthritis Patients

Objective: Long non-coding RNAs (lncRNAs) and their target microRNAs were documented in multiple studies to have a significant role in different joint disorders such as rheumatoid arthritis (RA) and osteoarthritis (OA). The current work aimed to determine the potential role of lnc-PVT1 and miR-146a as promising biomarkers to distinguish between RA, OA patients, and healthy individuals. Methods: The expression levels of lnc-PVT1 and its target miR-146a in the serum were measured for three different groups, including patients with RA (40), OA patients (40), and healthy controls (HCs) (40). Participating individuals were subjected to a full history investigation and clinical examination. Blood samples were tested for ESR, RF, CBC, as well as liver and renal functions. Serum was used to detect the relative expression levels of lnc-PVT1 and miR-146a and we correlated the levels with RA and OA activity and severity signs. Results: Lnc-PVT1 expression level was greater among patients with RA compared to that of OA patients, with a fold change median of 2.62 and 0.22, respectively (p = 0.001). The miR-146a fold change was significantly demonstrated between the RA, OA, and HCs groups. There was no correlation between both biomarkers with the disease activity scales (DAS28) of RA, the Knee injury Osteoarthritis Outcome Score (KOOS), or any sign of detection of the disease severity of OA. Conclusions: lnc-PVT1 and miR-146a could be considered as promising biomarkers for the diagnosis of RA and OA and may have an important role as therapeutic targets in the future.

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.

The ability to kneel before and after total knee arthroplasty : the role of the pattern of osteoarthritis and the position of the femoral component

AIMS

The aims of this study were to investigate the ability to kneel after total knee arthroplasty (TKA) without patellar resurfacing, and its effect on patient-reported outcome measures (PROMs). Secondary aims included identifying which kneeling positions were most important to patients, and the influence of radiological parameters on the ability to kneel before and after TKA.

METHODS

This prospective longitudinal study involved 209 patients who underwent single radius cruciate-retaining TKA without patellar resurfacing. Preoperative EuroQol five-dimension questionnaire (EQ-5D), Oxford Knee Score (OKS), and the ability to achieve four kneeling positions were assessed including a single leg kneel, a double leg kneel, a high-flexion kneel, and a praying position. The severity of radiological osteoarthritis (OA) was graded and the pattern of OA was recorded intraoperatively. The flexion of the femoral component, posterior condylar offset, and anterior femoral offset were measured radiologically. At two to four years postoperatively, 151 patients with a mean age of 70.0 years (SD 9.44) were included. Their mean BMI was 30.4 kg/m² (SD 5.36) and 60 were male (40%). They completed EQ-5D, OKS, and Kujala scores, assessments of the ability to kneel, and a visual analogue scale for anterior knee pain and satisfaction.

RESULTS

The ability to kneel in the four positions improved in between 29 (19%) and 53 patients (35%) after TKA, but declined in between 35 (23%) and 46 patients (30%). Single-leg kneeling was most important to patients. After TKA, 62 patients (41%) were unable to achieve a single-leg kneel, 76 (50%) were unable to achieve a double-leg kneel, 102 (68%) were unable to achieve a high-flexion kneel and 61 (40%) were unable to achieve a praying position. Posterolateral cartilage loss significantly affected preoperative deep flexion kneeling (p = 0.019). A postoperative inability to kneel was significantly associated with worse OKS, Kujala scores, and satisfaction (p < 0.05). Multivariable regression analysis identified significant independent associations with the ability to kneel after TKA (p < 0.05): better preoperative EQ-5D and flexion of the femoral component for single-leg kneeling; the ability to achieve it preoperatively and flexion of the femoral component for double-leg kneeling; male sex for high-flexion kneeling; and the ability to achieve it preoperatively, anterior femoral offset, and patellar cartilage loss for the praying position.

CONCLUSION

The ability to kneel was important to patients and significantly influenced knee-specific PROMs, but was poorly restored by TKA with equal chances of improvement or decline. Cite this article: Bone Joint J 2021;103-B(9):1514-1525.

Effects of education, income, and occupation on prevalence and symptoms of knee osteoarthritis

To examine the effect of socioeconomic status (SES) as measured by three components of education level, income level, and occupation on prevalence and symptom severity of knee osteoarthritis (OA) and to determine which of these factors has the strongest association. We conducted a cross-sectional study using data from the Fifth Korean National Health and Nutrition Examination Survey that were collected between 2010 and 2012. Male and female participants 50 years or older were included. Analyses to examine the associations of the three SES components with prevalence and symptom severity of knee OA were performed. A total 9,071 participants was included in the study. As expected, lower education, lower income level, and non-managerial or no job were associated with higher prevalence of knee OA and knee symptoms. Among the three SES components, lower education was most strongly associated with knee pain and radiographic knee OA after adjusting for the other two. Lower education level is the component of SES that most strongly relates to higher prevalence of knee OA and knee symptoms. Improving societal education level might decrease the socioeconomic burden of knee OA.

Arrabidaea chica Verlot fractions reduce MIA-induced osteoarthritis progression in rat knees

This study aims to investigate the activity of n-hexane, ethyl acetate and butanol fractions obtained from Arrabidaea chica Verlot against MIA-induced osteoarthritis (OA). The antinociceptive potentials of each fraction were evaluated through a cyclooxygenase (COX) 1 and 2 inhibition test and an in vivo OA-model. In addition, toxicity assessments in the liver, spleen and kidney, as well as radiographic and histopathological knee analyses, were performed. The chemical composition of the n-hexane fraction was elucidated, and a molecular docking protocol was carried out to identify which compounds are associated with the detected bioactivity. The n-hexane A. chica fraction preferentially inhibits COX-2, with 90% inhibition observed at 10 µg/mL. The fractions also produced significant improvements in OA incapacity, motor activity and hyperalgesia parameters and in radiological knee conditions. However, concerning the histopathological evaluations, these improvements were only significant in the hexane and ethyl acetate fraction treatments, which resulted in better average scores, suggesting that these fractions slow OA-promoted joint injury progression. Histopathological organ analyses indicate that the fractions are not toxic to animals. Twenty compounds were identified in the n-hexane fraction, comprising fatty acids, terpenes and phytosterols. In silico analyses indicate the presence of favourable interactions between some of the identified compounds and the COX-2 enzyme, mainly concerning alpha-tocopherol (Vitamin E), squalene and beta-sitosterol. The findings indicate that A. chica fractions display analgesic, anti-inflammatory properties, are non-toxic and are able to slow OA progression, and may, therefore, be prioritized as natural products in OA human clinical trials.

The Risk of Knee Osteoarthritis in Professional Soccer Players

BACKGROUND

We address the question whether professional soccer players with and without macroinjury of the knee joint are at an elevated risk for knee osteoarthritis.

METHODS

A systematic review with meta-analyses was conducted. The study protocol was prospectively registered (registration number CRD42019137139). The MEDLINE, EMBASE, and Web of Science databases were searched for relevant publications; in addition, forward searching was performed, and the listed references were considered. All steps of the process were undertaken independently by two reviewers, and any discordances were resolved by consensus. For all publications whose full text was included, the methods used were critically evaluated. The quality of the evidence was judged using the GRADE criteria.

RESULTS

The pooled odds ratio for objectively ascertained osteoarthrosis of the knee was 2.25 (95% confidence interval [1.41-3.61], I² = 71%). When only radiologically ascertained knee osteoarthrosis was considered, the odds ratio was 3.98 [1.34; 11.83], I² = 58%). The pooled risk estimator in studies in which knee joint macroinjury was excluded was 2.81 ([1.25; 6.32], I² = 71%).

CONCLUSION

A marked association was found between soccer playing and knee osteoarthritis in male professional soccer players. For female professional soccer players, the risk of knee osteoarthritis could not be assessed because of the lack of data. Knee injuries seem to play an important role in the development of knee osteoarthritis in professional soccer players.

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.

Data Integration Reveals the Potential Biomarkers of Circulating MicroRNAs in Osteoarthritis

The abnormal expression of circulating miRNAs (c-miRNAs) has become an emerging field in the development of miRNAs-based diagnostic and therapeutic tools for human diseases, including osteoarthritis (OA). OA is the most common form of arthritis leading to disability and a major socioeconomic burden. The abnormal expression of miRNAs plays important roles in the pathogenesis of OA. Unraveling the role of miRNAs in the pathogenesis of OA will throw light on the potential for the development of miRNAs-based diagnostic and therapeutic tools for OA. This article reviews and highlights recent advances in the study of miRNAs in OA, with specific demonstration of the functions of miRNA, especially c-miRNA, in OA pathogenesis as well as its potential implication in the treatment of OA. Based on a systematic literature search using online databases, we figured out the following main points: (1) the integrative systematic review of c-mRNAs and its target genes related to OA pathogenesis; (2) the potential use of c-miRNAs for OA diagnosis purposes as potential biomarkers; and (3) for therapeutic purposes, and we also highlight certain remedies that regulate microRNA expression based on its target genes.

Predominant lifetime occupation and associations with painful and structural knee osteoarthritis: An international participant-level cohort collaboration

Objective

With adults working to older ages, occupation is an important, yet less modifiable domain of physical activity to consider in the risk of knee osteoarthritis (OA). This study aimed to investigate the association between predominant lifetime occupation and prevalent knee OA.

Design

Participant-level data were used from five international community-based cohorts: Johnston County Osteoarthritis Project, the Hertfordshire Cohort Study, the Multicenter Osteoarthritis Study, the Tasmanian Cohort Study and Framingham Osteoarthritis Study. Self-reported predominant occupation was categorized into sedentary, light, light manual and heavy manual levels. Cross-sectional associations between predominant lifetime occupation and knee OA outcomes including prevalence of radiographic knee OA (RKOA), symptomatic RKOA and knee pain, were assessed using logistic regression, accounting for cohort clustering.

Results

Data for 7391 participants were included. 24.7% reported sedentary lifetime occupation, 30.0% light, 35.9% light manual and 9.4% heavy manual. 43.3% presented with RKOA, 52.1% with knee pain and 29.0% with symptomatic RKOA. There was over a two-fold increase in the odds of having RKOA, knee pain and symptomatic RKOA in those whose with heavy manual compared to sedentary occupations ((odds ratio (OR): 2.14; 95% confidence interval (CI): 1.79, 2.58), (OR: 2.19; 95% CI: 1.78, 2.70), (OR: 2.41; 95% CI: 1.94, 2.99) respectively).

Conclusion

This large international multi-cohort study demonstrated an association of heavy manual work with RKOA, symptomatic RKOA and knee pain. Measures that protect workers and are designed to reduce heavy manual related activities remain a priority to reduce the risk of knee OA.

Occupational Risk in Knee Osteoarthritis: A Systematic Review and Meta-Analysis of Observational Studies

OBJECTIVE

To assess the association between occupational exposures and knee osteoarthritis (OA).

METHODS

We systematically searched for observational studies that examined the relationship between occupational exposures and knee OA and total knee replacement. Four databases were searched up to October 1, 2019. Two reviewers independently assessed study quality using the Newcastle-Ottawa Scale and evidence quality using the Grading of Recommendations Assessment, Development and Evaluation approach. Subgroup meta-analyses were conducted for important study characteristics and each type of occupational exposure. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated for the meta-analysis using random-effects models.

RESULTS

Eighty eligible studies were identified including 25 case-control (n = 20,505 total participants), 36 cross-sectional (n = 139,463 total participants), and 19 cohort studies (n = 16,824,492 total participants). A synthesis of 71 studies suggested increased odds of knee OA (OR 1.52 [95% CI 1.37-1.69]) by combining different physically demanding jobs and occupational activities as compared to sedentary occupations and/or low-exposure groups. Odds of knee OA were greater in males and in industry-based studies and studies assessing lifetime occupational exposures. There were 9 specific job titles that were associated with knee OA, including farmer, builder, metal worker, and floor layer. Occupational lifting, kneeling, climbing, squatting, and standing were all associated with higher odds of knee OA as compared to the odds of knee OA in sedentary workers.

CONCLUSION

Strenuous, physically demanding occupations and occupational activities were associated with increased odds of knee OA as supported by moderate-quality evidence. Specifically, agricultural and construction sectors, which typically involve heavy lifting, frequent climbing, prolonged kneeling, squatting, and standing, carried increased odds of knee OA.

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.

Total Joint Arthroplasty Volume in the Military Health System

INTRODUCTION

The relationship between volume and outcome of total knee arthroplasties is a concern in both the civilian and military patient populations. We sought to compare surgeons and hospital procedure volumes performed on military service members and define factors leading to increased civilian referrals.

MATERIALS AND METHODS

The Military Health System Data Repository (MDR) contains patient information on all healthcare beneficiary encounters, including care provided both in Military Health System (MHS) facilities and in civilian network facilities. The Military Analysis and Reporting Tool (M2) queried the MDR for all patients between 2011 and 2015 with a CPT code for hip or knee arthroplasty associated with a provider HIPAA taxonomy code for orthopedic surgery. M2 enrollee encounters were used to calculate the total number of arthroplasty procedures performed by both military and civilian orthopedic surgeons on MHS enrollees as well as the incidence rate of arthroplasty procedures. Logistic regression was used to predict which cases were more likely to have been treated at military treatment facilities using patient gender, sponsor service branch, age, and beneficiary category.

RESULTS

During the study period, a total of 12,627 military facility arthroplasty cases and a total of 142,637 civilian facility arthroplasty cases were performed on TRICARE enrolled patients. The total number of military surgeons performing arthroplasty on TRICARE enrolled patients was 323, while the total number of civilian surgeons performing arthroplasty was 10,245 during the same time period; the number of military surgeons performing arthroplasty on active duty patients was 176, and the total number of civilian surgeons performing arthroplasty on military patients was 1045. Overall, including retirees and activity duty service members, more procedures are performed by civilian network surgeons than military surgeons in all states. In an adjusted model, male patients were slightly more likely to receive care at an military treatment facilitie than female patients (OR = 1.47, 95% CI: 1.41-1.53). Furthermore, with respect to service, patients with Air Force (OR: 1.08, 95% CI: 1.02-1.15) and Navy sponsors (OR: 1.61, 95% CI: 1.51-1.71) were more likely to receive military care than patients with Army sponsors.

CONCLUSIONS

Based on our findings, we recommend the MHS focus attention to recapturing the Army active duty male patients who are more likely to receive care outside of the military healthcare network. Further analysis of the many factors including, but not limited to, referral process for total joint arthroplasty, time to procedure, and facility resources is required, in addition to assessing patient outcomes following the procedures.

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.

Men and Women's Occupational Activities and the Risk of Developing Osteoarthritis of the Knee, Hip, or Hands: A Systematic Review and Recommendations for Future Research

Objective

To systematically review the evidence for an increased risk of osteoarthritis in the hip, knee, hand, wrist, finger, ankle, foot, shoulder, neck, and spine related to diverse occupational activities of men and women and to examine dose‐response information related to the frequency, intensity, and duration of work exposures and the risk of osteoarthritis (OA).

Methods

Established guidelines for systematic reviews in occupational health and safety studies were followed. MEDLINE, Embase, CINAHL, and Cochrane Library were searched from inception to December 2017. Studies were reviewed for relevance, quality was appraised, and data were extracted and synthesized.

Results

Sixty‐nine studies from 23 countries yielded strong and moderate evidence for lifting, cumulative physical loads, full‐body vibration, and kneeling/squatting/bending as increasing the risks of developing OA in men and women. Strong and moderate evidence existed for no increased risk of OA related to sitting, standing, and walking (hip and knee OA), lifting and carrying (knee OA), climbing ladders (knee OA), driving (knee OA), and highly repetitive tasks (hand OA). Variability in dose‐response data resulted in an inability to synthesize these data.

Conclusion

Evidence points to the potential for OA occupational recommendations and practice considerations to be developed for women and men. However, research attention is needed to overcome deficits in the measurement and recall of specific work activities so that recommendations and practice considerations can provide the specificity needed to be adopted in workplaces.

[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.

Detection of kneeling and squatting during work using wireless triaxial accelerometers

Occupational kneeling and squatting are well-documented risk factors for knee disorders. A method using 3 wireless accelerometers to detect and discriminate kneeling and squatting during work were developed based on data from a semi-standardised laboratory protocol. The method was tested for validity under free-living working conditions. The developed method showed high sensitivity (88-99%) and specificity (98-99%) for detection of kneeling and squatting during the semi-standardised laboratory conditions. During free-living working conditions, kneeling showed very high sensitivity (94%) and specificity (99%), while squatting results were non-conclusive due to limited duration of squatting during the free-living working conditions. This method shows great promise for long-term technical measurement of kneeling and squatting during normal working conditions using wireless accelerometers. The method opens up possibilities for using technical measurements to provide valid exposure assessments and intervention evaluations of kneeling and squatting, as well as increased feasibility for technical measurements in large cohort studies. Practitioner summary: Quantification of kneeling and squatting during work is important for prevention, but limited by either imprecise or costly methods. This study developed and validated an inexpensive wireless accelerometer-based measurement method that can be used by practitioners and researchers for long-term measurements of kneeling and squatting during free-living working conditions.

Machine-learning-based patient-specific prediction models for knee osteoarthritis

Osteoarthritis (OA) is an extremely common musculoskeletal disease. However, current guidelines are not well suited for diagnosing patients in the early stages of disease and do not discriminate patients for whom the disease might progress rapidly. The most important hurdle in OA management is identifying and classifying patients who will benefit most from treatment. Further efforts are needed in patient subgrouping and developing prediction models. Conventional statistical modelling approaches exist; however, these models are limited in the amount of information they can adequately process. Comprehensive patient-specific prediction models need to be developed. Approaches such as data mining and machine learning should aid in the development of such models. Although a challenging task, technology is now available that should enable subgrouping of patients with OA and lead to improved clinical decision-making and precision medicine.

Deciphering the Association of Cytokines, Chemokines, and Growth Factors in Chondrogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells Using an ex vivo Osteochondral Culture System

Osteoarthritis (OA) is a chronic degenerative joint disorder associated with degradation and decreased production of the extracellular matrix, eventually leading to cartilage destruction. Limited chondrocyte turnover, structural damage, and prevailing inflammatory milieu prevent efficient cartilage repair and restoration of joint function. In the present study, we evaluated the role of secreted cytokines, chemokines, and growth factors present in the culture supernatant obtained from an ex vivo osteochondral model of cartilage differentiation using cartilage pellets (CP), bone marrow stem cells (BM-MSCs), and/or BM-MSCs + CP. Multiplex cytokine analysis showed differential secretion of growth factors (G-CSF, GM-CSF, HGF, EGF, VEGF); chemokines (MCP-1, MIP1α, MIP1β, RANTES, Eotaxin, IP-10), pro-inflammatory cytokines (IL-1β, IL-2, IL-5, IL-6, IL-8, TNFα, IL-12, IL-15, IL-17) and anti-inflammatory cytokines (IL-4, IL-10, and IL-13) in the experimental groups compared to the control. In silico analyses of the role of stem cells and CP in relation to the expression of various molecules, canonical pathways and hierarchical cluster patterns were deduced using the Ingenuity Pathway Analysis (IPA) software (Qiagen, United States). The interactions of the cytokines, chemokines, and growth factors that are involved in the cartilage differentiation showed that stem cells, when used together with CP, bring about a favorable cell signaling that supports cartilage differentiation and additionally helps to attenuate inflammatory cytokines and further downstream disease-associated pro-inflammatory pathways. Hence, the autologous or allogeneic stem cells and local cartilage tissues may be used for efficient cartilage differentiation and the management of OA.

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.

Modifiable factors associated with symptomatic knee osteoarthritis: The Murakami cohort study

OBJECTIVES

Modifiable risk factors for knee osteoarthritis (OA) have not been studied in detail. This study aimed to determine lifestyle-related modifiable factors of symptomatic knee osteoarthritis in an East Asian population.

STUDY DESIGN

This 5-year cohort study involved 11,091 individuals (age range 40-72 years) living in the Murakami region of Niigata, Japan, who did not have a history of knee OA. At baseline, information on sociodemographic characteristics, body size, lifestyle, and living condition was obtained using a self-administered questionnaire.

MAIN OUTCOME MEASURES

Incident symptomatic knee OA observed at hospitals and orthopaedic clinics in the five years to 2016. Clinical grades of knee OA were based on the Kellgren-Lawrence scale. P for trend was assessed to examine linear associations between predictors and the outcome in multiple logistic regression analysis.

RESULTS

The mean age of participants was 58.1 (SD 9.3) years. The number of cases of grade 2 or more incident knee OA was 429. In men, older age (P for trend < 0.0001), higher BMI (P for trend < 0.0001), higher METs score (P for trend = 0.0150), less smoking (P for trend = 0.0249), and lower green tea consumption (P for trend = 0.0437) were associated with incident knee OA. In women, older age (P for trend < 0.0001), higher BMI (P for trend < 0.0001), and alcohol consumption (P = 0.0153) were associated with incident knee OA.

CONCLUSIONS

Several lifestyle-related factors were found to be associated with incident knee OA and exhibited sex-dependent differences. In particular, higher consumption of green tea was associated with a lower incidence of knee OA in men.

Kneeling ability after total knee replacement

Kneeling ability is consistently the poorest patient-rated outcome after total knee replacement (TKR), with 60-80% of patients reporting difficulty kneeling or an inability to kneel.Difficulty kneeling impacts on many activities and areas of life, including activities of daily living, self-care, leisure and social activities, religious activities, employment and getting up after a fall. Given the wide range of activities that involve kneeling, and the expectation that this will be improved with surgery, problems kneeling after TKR are a source of dissatisfaction and disappointment for many patients.Research has found that there is no association between range of motion and self-reported kneeling ability. More research is needed to understand if and how surgical factors contribute to difficulty kneeling after TKR.Discrepancies between patients' self-reported ability to kneel and observed ability suggests that patients can kneel but elect not to. Reasons for this are multifactorial, including knee pain/discomfort, numbness, fear of harming the prosthesis, co-morbidities and recommendations from health professionals. There is currently no evidence that there is any clinical reason why patients should not kneel on their replaced knee, and reasons for not kneeling could be addressed through education and rehabilitation.There has been little research to evaluate the provision of healthcare services and interventions for patients who find kneeling problematic after TKR. Increased clinical awareness of this poor outcome and research to inform the provision of services is needed to improve patient care and allow patients to return to this important activity. Cite this article: EFORT Open Rev 2019;4:460-467. DOI: 10.1302/2058-5241.4.180085.

Dietary magnesium intake, serum high sensitivity C-reactive protein and the risk of incident knee osteoarthritis leading to hospitalization-A cohort study of 4,953 Finns

Objectives

To study whether low dietary magnesium (Mg) intake and serum high sensitivity C-reactive protein (hs-CRP) predict the development of clinical knee osteoarthritis (OA).

Methods

The cohort consisted of 4,953 participants of a national health examination survey who were free of knee and hip OA at baseline. Information on the incidence of knee OA leading to hospitalization was drawn from the National Care Register for Health Care. During the follow-up of 10 years, 123 participants developed incident knee OA. Dietary magnesium intake was assessed on the basis of a food frequency questionnaire from the preceding year. We used Cox’s proportional hazards model to estimate the strength of the association between the tertiles of dietary Mg intake and incident knee OA, adjusted for baseline age, gender, energy intake, BMI, history of physical workload, leisure time physical activity, injuries, knee complaints, the use of Mg supplements, and serum hs-CRP levels.

Results

At baseline, dietary Mg intake was inversely associated with serum hs-CRP even after adjustment for all the potential confounding factors. During the follow-up, the adjusted hazard ratios (with their 95% confidence intervals) for incident knee OA in dietary Mg intake tertiles were 1.00, 1.28 (0.78–2.10), and 1.38 (0.73–2.62); the p value for trend was 0.31. Serum hs-CRP level at baseline did not predict incident knee OA.

Conclusions

The results do not support the hypothesis that low dietary Mg intake contributes to the development of clinical knee OA, although Mg intake is inversely associated with serum hs-CRP level.

Possible case of pressure resorption associated with osteoarthritis in human skeletal remains from ancient China

Osteoarthritis, one of the most common pathological conditions observed in human skeletal remains, is traditionally thought to only affect the structures within the joint capsule. We examined the osteoarthritic distal femora of an individual from Ancient North China, ca. 475-221 BCE. The standard signs of osteoarthritis, marginal lipping and extensive eburnation, were observed in the patellofemoral compartment of the knee joint. In addition however were bilateral pressure-caused fossae on the extra-articular anterior surfaces of the distal femora 10 mm proximal to the large osteophytes at the apex of the patellar surfaces. Anatomy and possible pathogenesis of knee arthritis are explored in order to come to a tentative aetiology of the extra-articular lesions. These lesions are suggested to be a new criterion for identifying severe knee arthritis. The osteological phenomenon is then placed into archaeological context of the Warring States period of ancient China.

Epidemiological profiles of chronic low back and knee pain in middle-aged and elderly Japanese from the Murakami cohort

Purpose

Epidemiological profiles of chronic low back and knee pain have not been studied extensively. This study aimed to determine the prevalence of and potential risk factors associated with chronic low back and knee pain in middle-aged and elderly Japanese.

Methods

This cross-sectional study involved 14,217 community-dwelling individuals aged 40–74 years living in the Murakami area of Japan. A self-administered questionnaire was used to obtain information regarding marital status, education level, occupation, household income, and body size. Participants also reported current chronic pain, if any, by site and degree of severity, using the verbal rating scale of the Short Form 36.

Results

The prevalence of moderate–very severe chronic pain was 9.7% in the low back, 6.7% in the knee, 13.9% in either the low back or knee, and 2.6% in both the low back and knee. Multivariate analysis revealed that lower education level, lower income, and manual occupation in men and older age and higher body mass index in women were significantly associated with a higher prevalence of chronic low back pain. In both sexes, older age, lower education level, and higher body mass index were significantly associated with a higher prevalence of knee pain. Regarding sex differences, adjusted ORs of chronic pain of the low back and knee for women were 0.85 (95% CI 0.75–0.97) and 1.27 (95% CI 1.09–1.49), respectively.

Conclusion

Nearly 14% of middle-aged and elderly individuals had moderate–very severe chronic pain of the low back or knee, and this pain was associated with many demographic factors, including sex, age, education level, household income, occupation, and body size.

Elucidating the environmental risk factors for rheumatic diseases: An umbrella review of meta-analyses

AIMS

Although rheumatic diseases constitute a leading cause of disability, the environmental risk factors for these diseases are not clarified. In the present study, we aim to systematically appraise the epidemiological credibility of the environmental risk factors for rheumatic diseases.

METHODS

We systematically searched PubMed to capture meta-analyses of observational studies on environmental risk factors for the most prevalent rheumatic diseases. For each association, we estimated the summary effect size estimate, the 95% confidence and prediction intervals, and the I² metric. We further examined the presence of small-study effects and excess significance bias.

RESULTS

Overall, we identified 30 eligible papers describing 42 associations. Thirty-three associations were statistically significant at P < 0.05, whereas 13 of them were statistically significant at P < 1 × 10^-6 . Thirty-two associations had large or very large between-study heterogeneity. In 12 associations, evidence of small-study effects and/or excess significance bias was found. Six risk factors (nine associations) presented convincing or highly suggestive evidence of association: smoking and pack-years of smoking for rheumatoid arthritis; BMI (per 5 kg/m² increase) for gout and hip osteoarthritis; alcohol consumption for gout; BMI (overweight vs lean, obese vs lean), knee injury and participation in heavy work for knee osteoarthritis.

CONCLUSION

Our umbrella review indicated that a narrow range of risk factors has been examined for rheumatic diseases. Current evidence strongly supports that smoking, obesity, alcohol consumption, knee injury, and work activities are associated with risk for at least one rheumatic disease.

The burden for knee osteoarthritis among Chinese elderly: estimates from a nationally representative study

OBJECTIVE

To estimate the burden of knee osteoarthritis (OA) among Chinese population.

DESIGN

Individuals with symptomatic knee OA based on self-reported physician-diagnosed arthritis and presence of knee pain were identified in China Health and Retirement Longitudinal Study. Severity of knee OA was divided into three categories: mild, moderate and severe, according to knee pain severity. We estimated sex-specific years lived with disability (YLD) and YLD rate (per 100,000 population) by multiplying the prevalence of knee OA with appropriate disability weight (DW) and examined associations between several key sociodemographic factors and YLDs.

RESULTS

Among 17,459 subjects (52.1% women; mean age 59.1 years) included in this analysis, prevalence of mild, moderate and severe knee OA was 1.5%, 3.3%, and 3.9%, respectively. The total number of YLDs for knee OA in China was 4,149,628, and YLDs per 100,000 population was 968. Female sex, older age, rurality, lower education, and lower gross domestic production (GDP) per capita were associated with high YLDs rates for knee OA, respectively. The North and East regions of China had the lowest YLD rate per 100,000 population for knee OA (631 and 699), followed by South-central (858), Northeast (878), and Northwest (1502) regions. Southwest region had the highest YLD rate from knee OA (1653).

CONCLUSIONS

In this nationally representative sample, we demonstrated a high burden from knee OA among Chinese population. YLD rate for knee OA varied significantly according to sociodemographic factors. Our study calls for an urgent need for health policy support and cost-effective preventive strategies in China.

Lower extremity osteoarthritis is associated with lower health-related quality of life among retired professional footballers

OBJECTIVE

The objective of the current study was to explore whether retired professional footballers suffering from lower extremity OA have a lower health-related quality of life than those without OA or current professional footballers.

METHODS

An observational study based on a cross-sectional design by means of questionnaires was conducted. Participants were retired and current professional footballers recruited by the World Players' Union (FIFPro). Information about lower extremity OA (clinically diagnosed by a medical professional) was gathered, while health-related quality of life (Global Physical Health and Global Mental Health scores) was assessed through a validated scale.

RESULTS

A total of 396 retired and 361 current professional footballers were included in the analyses (response rate of 54%). The group of retired professional footballers was on average 36 years old, and they had competed in professional football for 11 years (retired for 5 years). The group of current professional footballers was on average 25 years old, and they had been active in professional football for 7 years. Within the group of retired professional footballers, prevalence of lower extremity OA was 33%. Both Global Physical Health and Global Mental Health scores among retired professional footballers with lower extremity OA were significantly lower than among retired players without OA and current players, but these scores were nearly similar to the norm for the general population (regardless the presence of OA or not).

CONCLUSIONS

Health-related quality of life among retired professional footballers with lower extremity OA was significantly lower than among retired players without OA and current players but nearly similar to the norm for the general population (regardless the presence of OA or not). A rational recommendation is that a support measure such as the After Career Consultation should be introduced among retired professional footballers in order to empower their sustainable health and quality of life, focussing especially on the prevention of the occurrence or worsening of lower extremity OA.

Association of osteoarthritis risk factors with knee and hip pain in a population-based sample of 29-59 year olds in Denmark: a cross-sectional analysis

Background

This study aimed to a) describe the prevalence of knee and hip osteoarthritis risk factors in a population of 29–59 year old individuals, b) estimate the association between persistent knee/hip pain and osteoarthritis risk factors, and c) describe the prevalence of osteoarthritis risk factors, including specific biomechanical risk factors, in individuals with prolonged persistent knee or hip pain.

Methods

Participants completed the “Early Detection and Prevention” pilot study questionnaire, including items on presence of knee/hip pain within the last month and osteoarthritis risk factors. Individuals reporting knee/hip problems completed a second questionnaire, including items about most problematic joint and specific biomechanical osteoarthritis risk factors. After describing the prevalence of persistent knee/hip pain and osteoarthritis risk factors among respondents stratified for sex and age, logistic regression was used to estimate the strength of associations between osteoarthritis risk factors and presence of knee/hip pain. The prevalence of prolonged persistent pain (i.e. knee/hip pain reported at both questionnaires) and osteoarthritis risk factors among respondents with prolonged persistent knee and hip pain, were described.

Results

Two thousand six hundred sixty-one respondents completed the first survey. The one-month prevalence of persistent knee/hip pain was 27%. Previous knee/hip injury was associated with persistent knee/hip pain for both sexes in all age groups, while a family history of osteoarthritis was associated with persistent knee/hip pain in all age groups except for 29–39 year old men. A higher BMI was associated with persistent knee/hip pain in 40–59 year old women, and 50–59 year old men. Eight hundred sixty seven respondents completed the second questionnaire. Knee/hip injuries and surgeries were more common in individuals with prolonged persistent knee than hip pain.

Conclusions

Knee/hip pain within the last month was frequent among individuals aged 29–59 years. Multiple known osteoarthritis risk factors were associated with presence of knee/hip pain. Joint injury and previous surgery were more common in individuals with knee than hip pain. The results support the notion that joint injury and overweight during early adulthood are signs of a trajectory towards symptomatic osteoarthritis later in life and may help earlier identification of groups at high risk of future symptomatic osteoarthritis.

Trial registration

ClinicalTrials.gov (NCT02797392). Registered April 29,2016.

Knee osteoarthritis in professional football is related to severe knee injury and knee surgery

BACKGROUND

As a consequence of severe knee injuries, knee osteoarthritis (OA) seems prevalent in retired professional footballers. However, some epidemiological data remain missing, for instance whether knee OA is also prevalent in current professional footballers, whether knee OA is associated with knee injuries and surgeries, and whether knee OA leads to a lower level of functioning. Therefore, three research questions were answered: (i) what is the prevalence of knee osteoarthritis (OA) among current and retired professional footballers? (ii) is severe knee injury or knee surgery associated with knee OA among current and retired professional footballers? (iii) what are the consequences of knee OA on physical knee function among current and retired professional footballers?

METHODS

An observational study based on a cross-sectional design by means of questionnaires was conducted. Participants were current and retired professional footballers recruited by the World Players' Union (FIFPro). Information about severe knee injury and knee OA was gathered (medical record or team doctor), while physical knee function was assessed through a validated scale.

RESULTS

A total of 1360 participants (964 current and 396 retired professional footballers) were enrolled in the study (response rate of 54%). Prevalence of knee OA was 13% among current players and 28% among retired players (p < 0.01), being higher among older players. Current and retired professional footballers were nearly twice as likely to suffer from knee OA by every additional severe knee injury and by every additional knee surgery (risk ratio: 1.72-1.96; p < 0.01). Current and retired professional footballers with knee OA reported a lower level of physical knee function than current and retired players without OA (p < 0.01), their physical knee function being also lower than reference values (adult population, young athletic population and amateur footballers).

CONCLUSION

The prevalence of knee OA was higher among retired than among current professional footballers and reached up to 40%, leading to negative consequences for their physical knee function. Current and retired professional footballers were nearly twice as likely to suffer from knee OA by every additional severe knee injury and by every additional knee surgery incurred during their career. Management of knee OA should be prioritized among professional footballers, especially to prevent the worsening of the condition during their retirement years.

The effects of a simulated occupational kneeling exposure on squat mechanics and knee joint load during gait

Occupational kneeling is associated with an increased risk for tibiofemoral knee osteoarthritis. Forces on the knee in the kneeling posture, as well as the greater incidence of meniscus tears among workers, likely contribute to the increased risk. We hypothesise that an additional mechanism may contribute - altered neuromuscular control due to prolonged high knee flexion. Forty participants (20 male, 20 female) completed an evaluation of gait and squatting before, immediately following, and 30 min following a 30 min simulated occupational kneeling exposure. An increase in the peak external knee adduction moment and a delay in vastus medialis activation onset during walking were observed post-kneeling, as well as increased frontal plane knee motion during squatting. This was the first investigation to find changes in high flexion transitions as a result of kneeling. Greater frontal plane knee motion may increase the risk for meniscal tears, and subsequently, knee osteoarthritis. Practitioner Summary: A 30 min simulated occupational kneeling exposure resulted in small but significant gait changes. The greatest effect was on frontal plane knee movement during squatting, which is especially relevant to occupations requiring frequent kneeling/squatting. This increased motion may indicate an increased risk of injury, which supports a link to knee osteoarthritis.

Prevalence of musculoskeletal disorders in subjects not exposed to biomechanical overload

BACKGROUND

Data on the prevalence of work-related musculoskeletal disorders (WMSDs) in groups of unexposed subjects may serve for comparison in studies on risk/damage in groups of exposed subjects and for the planning of preventive interventions.

OBJECTIVES

To assess the musculoskeletal health status in a group of working subjects not exposed to biomechanical overload.

METHODS

Medical histories were collected by occupational health physicians as part of an active health surveillance program. An ad hoc questionnaire was administered to the subjects to detect musculoskeletal disorders.

RESULTS

The sample consisted of 1023 subjects (605 females and 418 males) with a mean age of 40 years. The prevalence of acute low back pain and disc hernia was 4% and 5.6% respectively; 4.3% of subjects were affected by at least one disorder of the upper limbs while the prevalence of knee disorders was 1.7%. Standardized data proved to be in line with previous studies with the exception of a greater prevalence of shoulder disorders and disc hernia.

CONCLUSIONS

WMSDs occur ubiquitously across the general working population unexposed to biomechanical overload. Such findings represent a valid reference for groups of exposed working subjects, in that any excess of such disorders/pathology may be due to specific work conditions.

Identification of influential demographic and work-related risk factors associated to lower extremity pain perception among rice farmers

BACKGROUND

A high prevalence of musculoskeletal disorders and abnormal alignments of the lower extremities (LE) was found for rice farmers. It is important to investigate demographic and work-related risk factors associated with LE pain prior to developing intervention strategies addressing the problematic factors of the highest-risk task.

OBJECTIVE

To identify factors associated with LE pain in rice farmers for every stage of the cultivation process.

METHODS

Thirty experienced farmers (age of 45.9±6.21 (mean±SD)) rated LE pain experienced before and after each cultivation stage using the Standardized Nordic Questionnaire. Risk factors of pain were characterized based on expert risk assessment of tasks due to force, posture and motion, in addition to a conventional survey of demographic and other work-related information.

RESULTS

Ergonomic risk factors were found to be the strongest predictors of knee and foot pain perception, which induced a substantial increase of pain perception (up to 4.6 times) with varying extent for individual cultivation stages. The highest risk and pain perception was found during the planting performance. Age exhibited significantly positive association with foot pain during planting and harvesting. However, more experienced farmers perceived less foot pain, presumably by developing effective movement strategies.

CONCLUSIONS

The findings suggest that the planting process should be subject of further intervention development, especially for older farmers, with focus on reducing force, awkward posture and repetitive movement to minimize risk of LE pain.

Understanding Occupation, Sick Leave, and Disability Pension Due to Knee and Hip Osteoarthritis From a Sex Perspective

OBJECTIVE

To investigate the association between occupation and risk for sick leave or disability pension due to knee or hip osteoarthritis (OA) from a sex perspective.

METHODS

We conducted a population-based study including residents ages 40-70 years in the Skåne region, Sweden (2007) and working in the included job sectors (n = 165,179). We retrieved data on cause-specific sick leave and disability pension (2007-2012) and linked to individual information on occupation and education (2007). Occupations were classified into job sectors. We calculated sex-specific, age-adjusted odds ratios (ORs) of sick leave and disability pension due to OA in traditionally female-dominated job sectors (health care, child care, and cleaning) and traditionally male-dominated job sectors (construction, farming, metal work, or transportation) compared to business and administration.

RESULTS

Of all eligible subjects, 2,445 had sick leave or disability pension due to knee or hip OA. Adjusted for age, the risk of sick leave due to knee OA was increased for women working in health care, with an OR of 3.3 (95% confidence interval [95% CI] 2.6-4.2), child care OR 2.9 (95% CI 2.2-3.8), and cleaning OR 3.0 (95% CI 2.2-4.1), as was the risk for disability pension. The risk was increased also for persons working in occupations with higher educational requirements. The risk was similarly increased in male-dominated sectors. In female-dominated job sectors the risk of sick leave and disability pension due to knee OA, but not hip OA, was higher than that for other musculoskeletal diseases.

CONCLUSION

Traditionally female-dominated occupational sectors are associated with an increased risk of sick leave and disability pension due to knee OA.