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.
Bias (Epidemiology) ; Cohort Studies ; Knee* ; Lifting ; Occupational Diseases ; Occupational Exposure* ; Odds Ratio ; Osteoarthritis* ; Osteoarthritis, Knee

This study sought to demonstrate bone mineral density (BMD) conditions in elderly female patients with knee osteoarthritis (OA) undergoing total knee arthroplasty (TKA). In addition, we sought to determine whether their BMD conditions differ from those of community-based females without knee OA. Finally we sought to determine whether clinical statuses are related to BMD in the knee OA patients. BMD conditions in 347 female patients undergoing TKA and 273 community-based females were evaluated. Additionally, comparative analyses of BMD between age and body mass index-matched knee OA groups (n=212) and the control groups (n=212) were performed. In the pre-matched knee OA group, regression analyses were performed to determine whether preoperative clinical statuses were related to BMD. Considerable prevalence of coexistent osteoporosis (31%) was found in the pre-matched knee OA patients undergoing TKA. We found no significant differences of the BMD T-scores and the prevalence of osteoporosis between the age and body mass index-matched knee OA and control groups. In the pre-matched knee OA patients, poorer preoperative clinical scores were related to poorer BMD T-scores in the proximal femur and/or lumbar spine. Our study suggests that more attention should be paid to identify and treat osteoporosis in elderly female patients with advanced knee OA undergoing TKA.
Aged ; Aged, 80 and over ; *Arthroplasty, Replacement, Knee ; Body Mass Index ; Bone Density ; Female ; Humans ; Knee Joint/pathology/surgery ; Osteoarthritis, Knee/*epidemiology/*surgery ; Osteoporosis/*epidemiology

OBJECTIVETo investigate the assosiation between squatting and the prevalence of knee osteoarthritis (OA) among elders in Beijing.

METHODSWe recruited a random sample of Beijing residents age > or =60 years. Subjects answered questions on joint symptoms, and knee radiographs were obtained. Subjects were also asked to recall the average amount of time spent on squatting each day at youth (25 years or so).

RESULTSAmong the studied subjects, 40% of the men and 68% of the women reported squatting > or = 1 hour per day at youth. The prevalence of tibiofemoral OA increased in both men and women. Compared with subjects who squatted <30 minutes per day at youth, the multivariable-adjusted prevalence odds ratios of tibiofemoral OA were: 1.1 30-59 minutes/day for those spent on squatting, 1.0 for 60-119 minutes/day, 1.7 for 120-179 minutes/day, and 2.0 for 180 minutes/day among the men (P for trend= 0.074), while the respective odda ratios among women were 1.4, 1.3, 1.2 and 2.4 (P for trend = 0.077) but a weaker association with patellofemoral OA was found.

CONCLUSIONProlonged squatting was a strong risk factor for tibiofemoral knee OA among elderly in Beijing.

Aged ; China ; Female ; Humans ; Male ; Middle Aged ; Osteoarthritis, Knee ; epidemiology ; Posture ; Prevalence ; Risk Factors

BACKGROUNDOsteoarthritis (OA) is the most common form of human polyarthritis. Many genetic factors have been implicated in OA. It was reported that a polymorphism in the gene of interleukin-6 (IL-6) was associated with OA of knee. The aim of this study was to determine whether functional IL-6 promoter -174G/C (rs1800795) polymorphisms confer susceptibility to knee OA.

METHODSA meta-analysis was conducted on the association between the IL-6 polymorphism and knee OA. Electronic search at PubMed, EMBASE, Weipu database, and Wanfang database was conducted to select studies. Case-control studies containing available genotype frequencies of IL-6 -174G/C were chosen, and odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of this association.

RESULTSA total of seven studies involving 6 464 subjects (knee OA 3 331 and controls 3 133) were considered in this study. The results suggested that the variant genotypes were not associated with knee OA risk in all genetic models (additive model: OR = 1.144, 95% CI 0.934-1.402, P = 0.194; recessive model: OR = 1.113, 95% CI 0.799-1.550, P = 0.526; dominant model: OR = 1.186, 95% CI 0.918-1.531, P = 0.191). A symmetric funnel plot, the Begg's test (P > 0.05), suggested that the data lacked publication bias.

CONCLUSIONSThis meta-analysis does not support the idea that rs1800795 genotype is associated with increased risk of knee OA. However, to draw comprehensive and more reliable conclusions, further prospective studies with larger numbers of participants worldwide are needed to examine the association between rs1800795 polymorphism and knee OA.

Humans ; Interleukin-6 ; genetics ; Osteoarthritis, Knee ; epidemiology ; genetics ; Polymorphism, Genetic ; genetics ; Promoter Regions, Genetic ; genetics

BACKGROUND: Knee osteoarthritis is highly prevalent, especially among the elderly. However, its risk factors have not been well identified, especially in the Korean population. This study aimed to assess the epidemiologic characteristics and risk factors of knee osteoarthritis in the Korean population. METHODS: Data of 2,280 (1,295 women) participants of the 2013 Korea National Health and Nutrition Examination Survey aged ≥50 years who underwent knee radiography were analyzed. According to the American College of Rheumatology clinical/radiographic classification criteria, knee osteoarthritis was defined as knee pain and radiographic knee osteoarthritis. The association between risk factors and knee osteoarthritis was analyzed using the chi-square test and binominal logistic regression. RESULTS: The participants had an average age of 62.6 years; 56.8% of them were women. The average body mass index was 24.2 kg/m2, and 296 (13%) participants were diagnosed with knee osteoarthritis. After adjustment for multiple risk factors, age of ≥65 years (adjusted odds ratio [OR], 2.552; 95% confidence interval [CI], 1.868–3.486), female sex (OR, 2.050; 95% CI, 1.275–3.295), obesity (body mass index, ≥25.0 kg/m2; OR, 1.563; 95% CI, 1.191–2.051), hypertension (OR, 1.394; 95% CI, 1.052–1.846), low educational level (lower than or equal to elementary school: OR, 4.761; 95% CI, 2.131–10.635; middle school: OR, 3.184; 95% CI, 1.375–7.369), and low strength exercise frequency (<2 times/wk; OR, 1.829; 95% CI, 1.202–2.784) increased the risk of knee osteoarthritis. CONCLUSION: Old age, sex, obesity, hypertension, low educational level, and low strength exercise frequency were found to be risk factors for knee osteoarthritis.
Aged ; Body Mass Index ; Classification ; Epidemiology ; Female ; Humans ; Hypertension ; Knee ; Korea ; Logistic Models ; Nutrition Surveys ; Obesity ; Odds Ratio ; Osteoarthritis ; Osteoarthritis, Knee ; Prevalence ; Radiography ; Rheumatology ; Risk Factors

OBJECTIVE: Osteoarthritis is one of the most common joint disorder in the world. But unfortunately there is no fundamental data as to its prevalence and risk factors in Korean population. We performed this study to understand the prevalence and risk factors related to knee osteoarthritis in Koreans. MATERIALS AND METHODS: A total 867 persons aged 20-69 years were selected from the general population in Kuri city and underwent a structured interview, clinical examination of knee joint, and radiologic study. The diagnostic criteria of knee osteoarthritis which we used was composed of clinical and radio- logical criteria reported by Altman et al. General characteristics of prevalence of knee osteoarthritis in relation to age, sex, education, job were evaluated. Risk factors such as obesity, menopause, physical activity, smoking, drinking, osteoporosis, diabetes mellitus, hypertension were evaluated by chi-squre test and logistic regression. RESULTS: This study revealed that prevalence of knee osteoarthritis in Korea is 10.2%, increasing with age. High level of physical activity in men and age, postmenopause and obesity in women can be risk factors.
Diabetes Mellitus ; Drinking ; Education ; Epidemiology* ; Female ; Humans ; Hypertension ; Joints ; Knee Joint ; Knee* ; Korea ; Logic ; Logistic Models ; Male ; Menopause ; Motor Activity ; Nutrition Surveys* ; Obesity ; Osteoarthritis ; Osteoarthritis, Knee* ; Osteoporosis ; Postmenopause ; Prevalence ; Risk Factors ; Smoke ; Smoking

BACKGROUND: One out of three adults over the age of 65 years and one out of two over the age of 80 falls annually. Fall risk increases for older adults with severe knee osteoarthritis, a matter that should be further researched. The main purpose of this study was to investigate the history of falls including frequency, mechanism and location of falls, activity during falling and injuries sustained from falls examining at the same time their physical status. The secondary purpose was to determine the effect of age, gender, chronic diseases, social environment, pain elsewhere in the body and components of health related quality of life such as pain, stiffness, physical function, and dynamic stability on falls frequency in older adults aged 65 years and older with severe knee osteoarthritis. METHODS: An observational longitudinal study was conducted on 68 patients (11 males and 57 females) scheduled for total knee replacement due to severe knee osteoarthritis (grade 3 or 4) and knee pain lasting at least one year or more. Patients were personally interviewed for fall history and asked to complete self-administered questionnaires, such as the 36-item Short Form Health Survey (SF-36) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC), and physical performance test was performed. RESULTS: The frequency of falls was 63.2% for the past year. The majority of falls took place during walking (89.23%). The main cause of falling was stumbling (41.54%). There was a high rate of injurious falling (29.3%). The time patients needed to complete the physical performance test implied the presence of disability and frailty. The high rates of fall risk, the high disability levels, and the low quality of life were confirmed by questionnaires and the mobility test. CONCLUSIONS: Patients with severe knee osteoarthritis were at greater risk of falling, as compared to healthy older adults. Pain, stiffness, limited physical ability, reduced muscle strength, all consequences of severe knee osteoarthritis, restricted patient's quality of life and increased the fall risk. Therefore, patients with severe knee osteoarthritis should not postpone having total knee replacement, since it was clear that they would face more complicated matters when combining with fractures other serious injuries and disability.
Accidental Falls/*statistics & numerical data ; Aged ; Aged, 80 and over ; Female ; Humans ; Longitudinal Studies ; Male ; Osteoarthritis, Knee/*epidemiology ; Quality of Life ; Risk

OBJECTIVETo investigate the incidence rate of anterior knee pain after total knee arthroplasty (TKA) and identify the related factors.

METHODSThis prospective, double-blind clinical trial involved a total of 128 patients scheduled for primary ipsilateral cemented three-component TKA for osteoarthrosis. The patients were randomized into two groups to receive operations for TKA with patellar resurfacing (experimental group) or not (control). The incidence of anterior knee pain was observed in these patients and the factor affecting the occurrence of anterior knee pain and knee was analyzed.

RESULTSThe patients were followed up for a mean of 16.5 months (range 6~24 months). The incidence rate of anterior knee pain was 10.9% (7/64) in the experimental group, showing no significant difference from the rate of 14.1% (9/64) in the control group. But the 52 patients with varus or valgus knee showed a significantly higher incidence rate of anterior knee pain (21.2%, 11/52).

CONCLUSIONTKA with patellar resurfacing can not decrease the incidence of anterior knee pain, and varus or valgus before the operation is associated with a higher risk of anterior knee pain.

Aged ; Arthroplasty, Replacement, Knee ; adverse effects ; methods ; China ; epidemiology ; Denervation ; methods ; Double-Blind Method ; Female ; Humans ; Knee Joint ; blood supply ; Male ; Middle Aged ; Osteoarthritis, Knee ; surgery ; Patella ; surgery ; Patellofemoral Pain Syndrome ; epidemiology ; etiology ; physiopathology ; Risk Factors

INTRODUCTIONLocal data on revision total knee arthroplasty (TKA) are limited. This study aims to assess the causes and outcomes of revision TKA in a single institution, with a 2-year follow-up.

MATERIALS AND METHODSA retrospective review of case records of patients who underwent revision TKA in 2008 and 2009 in the authors' institution was performed. Outcome was assessed using SF-36, Oxford knee score and Knee Society Clinical Rating System preoperatively, at 6 months and at 2 years' follow-up.

RESULTSForty-one patients (41 knees) were included in the study. Indications for revision were aseptic loosening in 13 (31.7%), mechanical wear/component failure in 10 (24.4%), infection in 9 (22.0%), malalignment in 4 (9.8%), instability in 3 (7.3%), periprosthetic fracture in 1 (2.4%) and persistent stiffness in 1 (2.4%). Significant improvements were seen postoperatively in all 3 instruments used to evaluate clinical outcome. These improvements were seen at 6 months after surgery, and were maintained through the 2-year follow-up period. There were no significant changes in all scores between 6 months and 2 years follow-up. There was 100% survivorship of the implants with no postoperative complications requiring surgical intervention.

CONCLUSIONIndications for revision TKA locally are similar to those in other large centres. Revision total knee arthroplasty results in significantly improved function and quality of life for patients, which is maintained over a 2-year follow-up period. In our series, we obtained 100% implant survivorship.

Aged ; Arthroplasty, Replacement, Knee ; Female ; Follow-Up Studies ; Humans ; Incidence ; Knee Prosthesis ; Male ; Middle Aged ; Osteoarthritis, Knee ; surgery ; Postoperative Complications ; epidemiology ; Prosthesis Failure ; Reoperation ; Retrospective Studies ; Singapore ; epidemiology ; Time Factors

BACKGROUNDFew data are available concerning intercondylar notch dimensions in female nonathletes with knee osteoarthritis (OA) in plateau region. The aim of this study was to assess the relation of intercondylar notch morphology to anterior cruciate ligament (ACL) injuries in female nonathletes with knee OA aged 41-65 years from the Chinese Loess Plateau.

METHODSThe study was conducted on 330 patients with ACL injury (aged 31-65 years; 159 males, 171 females), 141 patients with OA (aged 31-65 years; 59 males, 82 females), and 89 female healthy controls (aged 41-65 years), and this evaluation included identifying the distribution of patients with OA or ACL injury and measuring the intercondylar notch width indexes (NWIs).

RESULTSThere was a significant rising trend in patients with OA (the Kellgren and Lawrence grade = 3) with ACL injury (OA-S + ACL) aged 41-65 years, especially in females. We found that the notches of OA-S + ACL had a smaller NWI compared with control and OA without ACL injury (OA-S-only, P = 0.000, 95% confidence interval [CI] = -0.059--0.030; P = 0.000, 95% CI = -0.049--0.016). A similar trend was found in notch shape index (NSI), but not in notch depth index and the cross-sectional area. The cutoff of NWI and NSI value was 0.26, and 0.65, and area under the receiver operating characteristic curve was 0.82, and 0.79, respectively. Further study displayed a significant correlation between a reduced NWI and NSI and OA-S + ACL (P = 0.000, χ2 = 14.012; P = 0.000, χ2 = 14.286).

CONCLUSIONA narrower intercondylar notch and a plateau environment are risk factors of predisposing female nonathletes with knee OA to ACL injury aged 41-65 years.

Adult ; Aged ; Anterior Cruciate Ligament Injuries ; diagnosis ; epidemiology ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Osteoarthritis, Knee ; diagnosis ; epidemiology ; Risk Factors