Community Deprivation Index and Discharge Destination After Elective Hip Replacement.

OBJECTIVE: To examine how the deprivation level of the community in which one lives influences discharge disposition and the odds of 90-day readmission after elective total hip arthroplasty (THA). METHODS: We performed a retrospective cohort study on 84,931 patients who underwent elective THA in the Pennsylvania Health Care Cost Containment Council database from 2012 to 2016. We used adjusted binary logistic regression models to test the association between community Area Deprivation Index (ADI) level and patient discharge destination as well as 90-day readmission. We included an interaction term for community ADI level and patient race in our models to assess the simultaneous effect of both on the outcomes. RESULTS: After adjusting for patient- and facility-level characteristics, we found that patients from high ADI level communities (most disadvantaged), compared to patients from low ADI level communities (least disadvantaged), were more likely to be discharged to an institution as opposed to home for postoperative care and rehabilitation (age <65 years adjusted odds ratio [ORadj ] 1.47; age ≥65 years ORadj 1.31; both P < 0.001). The interaction effect of patient race and ADI level on discharge destination was statistically significant in those patients age ≥65 years, but not in patients age <65 years. The association with ADI level on 90-day readmission was not statistically significant. CONCLUSION: In this statewide sample of patients who underwent elective THA, the level of deprivation of the community in which patients reside influences their discharge disposition, but not their odds of 90-day readmission to an acute-care facility.

Common variants in IL17F gene contributed to the risk of hip osteoarthritis susceptibility in Han Chinese population.

AIM: The prevalence of hip and knee osteoarthritis (OA) varies by ethnicity, suggesting genetic heterogeneity in populations and predilection sites. Given the unknown mechanism of IL17F gene in the etiology of OA, it is necessary to examine the potential shared susceptibility of IL17F gene between knee OA and hip OA (HOA). This study aimed to evaluate the association of the IL17F gene and susceptibility to HOA in a Han Chinese population. METHODS: A total of 2650 study subjects, comprising 796 HOA patients and 1854 controls, were recruited into the present study. Seven tag single nucleotide polymorphisms (SNPs) were selected for genotyping. Single marker-based genetic association analyses were conducted at both the genotypic and allelic levels. χ2 statistics were calculated for statistical testing, and odds ratios were obtained to estimate the effects of genotypes and alleles for each SNP. RESULTS: The SNP rs763780 was identified to be significantly associated with the risk of HOA at both genotypic (χ2  = 12.45, P = .002) and allelic levels (χ2  = 11.83, P = .0006). A linkage disequilibrium (LD) block comprised of 3 SNPs (rs12201582-rs12203736-rs722323) was also significantly associated with the risk of HOA. In addition, rs2294835 was identified to be associated with HOA severity (χ2  = 12.10, P = .02). CONCLUSION: Our results showed that IL17F gene contributed to the risk of HOA in a Han Chinese population, which would help to elucidate the pathogenesis of OA and facilitate the development of novel medicines and treatments for OA.

Common variants in LTBP3 gene contributed to the risk of hip osteoarthritis in Han Chinese population.

Osteoarthritis (OA) is a common chronic joint disease affected by environmental and genetic factors. The LTBP3 gene may be involved in the occurrence and development of OA by regulating TGF-ß activity and the TGF-ß signaling pathway. A total of 2780 study subjects, including 884 hip OA cases and 1896 controls, were recruited. Nine tag single-nucleotide polymorphisms (SNPs) located within the LTBP3 gene region were selected for genotyping. Genetic association analyses were performed at both the genotypic and allelic levels. GTEx data were extracted to investigate the functional consequence of significant SNPs. SNP rs10896015 was significantly associated with the risk of hip OA at both the genotypic (P=0.0019) and allelic levels (P=0.0009). The A allele of this SNP was significantly associated with a decreased risk of HOA (OR [95%CI] = 0.79 [0.69-0.91]). This SNP was also significantly associated with the clinical severity of hip OA. SNP rs10896015 could affect the gene expression of 11 genes, including LTBP3, in multiple human tissues based on GTEx data. We obtained evidence for a genetic association between the LTBP3 gene and hip OA susceptibility and clinical severity based on Chinese Han populations. Our findings replicated the association signals reported by a recent genome-wide association study and deepen the basic understanding of osteoarthritis pathology.

Differences between race and sex in measures of hip morphology: a population-based comparative study.

OBJECTIVE: This paper aims to (i) identify differences in measures of hip morphology between four racial groups using anteroposterior (AP) hip x-rays, and (ii) examine whether these differences vary by sex. METHODS: 912 hip x-rays (456 individuals) from four racial groups (European Caucasians, American Caucasians, African Americans and Chinese) were obtained. Males and females (45-75 years) with no radiographic hip OA (Kellgren and Lawrence < Grade 2 or Croft < Grade 1) were included. Eleven features of hip joint morphology were analysed. Linear regression with generalised estimating equations (GEE) was used to determine race and sex differences in hip morphology. Post-hoc Bonferroni procedure was used to adjust for multiple comparisons. RESULTS: The final analysis included 875 hips. Chinese hips showed significant differences for the majority of measures to other racial groups. Chinese were characterised by more shallow and narrow acetabular sockets, reduced femoral head coverage, smaller femoral head diameter, and a lesser angle of alignment between the femoral neck and shaft. Variation was found between other racial groups, but with few statistically significant differences. The average of lateral centre edge angle, minimum neck width and neck length differed between race and sex (p-value for interaction < 0.05). CONCLUSIONS: Significant differences were found in measures of morphology between Chinese hips compared to African Americans or Caucasian groups; these may explain variation in hip OA prevalence rates between these groups and the lower rate of hip OA in Chinese. Sex differences were also identified, which may further explain male-female prevalence differences for OA.

Nonsteroidal Anti-Inflammatory Drug Use in Chronic Arthritis Pain: Variations by Ethnicity.

PURPOSE: Our objective was to determine if there are ethnic differences in the use of over-the-counter (OTC) and prescription oral nonsteroidal anti-inflammatory drugs (NSAIDs) and if observed ethnic differences persist after adjustment for sociodemographic and clinical factors. METHODS: Knee and hip osteoarthritis study participants were identified. Surveys were administered to collect sociodemographics, clinical information, and oral treatment methods for arthritis. Multivariable logistic regression models were created using a fully conditional method. RESULTS: Hispanics (n = 130), compared to non-Hispanic whites (n = 204), were less likely to have a high school education (26.9% vs 63.2%, P <0.001), less likely to have private medical insurance (P <0.001), and more likely to have worse health (P = 0.004). OTC oral NSAID use was less common (52.9% vs 66.3%, P = 0.019), whereas prescription oral NSAID use was more common (43.4% vs 31.7%, P = 0.042) among Hispanics than non-Hispanic whites in the last 6 months. The ethnic difference in using an OTC NSAID instead of not using any oral NSAID was attenuated and no longer significant when adjusted for age, sex, education, and medical insurance (odds ratio [OR] 0.54 [95% confidence interval [CI]: 0.28-1.02]). The odds of using a prescription instead of an OTC NSAID remained significantly higher among Hispanics than non-Hispanic whites when adjusted for the same variables (odds ratio 2.17 [95% confidence interval: 1.16-4.05]). CONCLUSIONS: Among patients with osteoarthritis, OTC NSAIDs were less commonly used but prescription NSAIDs were more commonly used by Hispanics than non-Hispanic whites. Sociodemographic factors partially mediate ethnic differences in the use of oral NSAIDs.

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

OBJECTIVES: To (1) explore the regional and ethnic differences in rates of publicly funded osteoarthritis-associated hip and knee replacement surgeries and (2) investigate the mortality after surgery. DESIGN: Population-based, retrospective, cross-sectional study. SETTING: General population in New Zealand. PARTICIPANTS: Patients with osteoarthritis who underwent publicly funded primary hip and knee replacement surgeries in 2005-2017. Patients aged 14-99 years were included. PRIMARY AND SECONDARY OUTCOME MEASURES: Age-standardised rate, standardised mortality ratio (SMR) and 30 days, 90 days and 1 year mortality. RESULTS: We identified 53 439 primary hip replacements and 50 072 primary knee replacements with a diagnosis of osteoarthritis. The number and age-standardised rates of hip and knee replacements increased over time. Maori had the highest age-standardised rate of hip replacements, followed by European/others and Pacific, and Asian had the lowest rate. Pacific had the highest age-standardised rate of knee replacements, followed by Maori and European/others, and Asian had the lowest rate. The Northern Health Network had the lowest rate of hip surgeries, and the Southern Health Network had the lowest rate of knee surgeries. The SMRs of patients undergoing hip and knee replacements were lower than the general population: 0.92 (95% CI 0.89 to 0.95) for hip and 0.79 (95% CI 0.76 to 0.82) for knee. The SMRs were decreasing over time. The patterns of 30 days, 90 days and 1 year mortality were similar to the SMR. CONCLUSIONS: The numbers of publicly funded osteoarthritis-associated primary hip and knee replacements are steadily increasing. Maori people had the highest age-standardised rate of hip replacements and Pacific people had the highest rate of knee replacements. The Northern Health Network had the lowest rate of hip surgeries, and the Southern Health Network had the lowest rate of knee surgeries. Compared with the general population, patients who had hip and knee replacements have a better life expectancy.

Modifiable Determinants of Exercise Use in a Diverse Ethnic Population With Osteoarthritis.

OBJECTIVE: To determine the extent of ethnic differences in the use of exercise for therapy and identify relevant modifiable determinants of exercise use among patients with knee/hip osteoarthritis (OA). METHODS: Knee/hip OA study participants were identified. Surveys were administered to collect patient sociodemographic and clinical information, and beliefs and attitudes about providers and treatments. Final multivariable logistic regression models were created using a fully conditional method. RESULTS: Hispanic participants (n = 130), compared to non-Hispanic participants (n = 232), were less likely to have private medical insurance (9.2% versus 31.0%) or to report having excellent/very good health (40.7% versus 52.6%). They were also less likely to report using exercise for OA treatment in the last 6 months (56% versus 73%; P = 0.003). When adjusted for age and disease severity, the difference in exercise use among ethnicities remained significant (odds ratio [OR] 0.59 [95% confidence interval (95% CI) 0.36-0.99]). In a multivariable logistic regression model designed to determine the most important determinants of exercise use for OA treatment, in the last 6 months the following were all associated with exercise use: having knee instead of hip OA (OR 2.83 [95% CI 1.51-5.29]), having family/friends who exercise (OR 3.20 [95% CI 1.76-5.84]), having a good understanding of what happens after exercise (OR 2.19 [95 CI 1.15-4.19]), and higher perceived benefit of exercise (OR 2.24 [95% CI 1.64-3.04]). CONCLUSION: Among patients with knee/hip OA, Hispanics were less likely to exercise for OA treatment. Increased knowledge about the benefits of exercise for treatment and improved familiarity with exercise as treatment for OA may increase exercise use.

The Effect of Payer Type on Patient-Reported Outcomes in Total Joint Arthroplasty Is Modulated by Baseline Patient Characteristics.

BACKGROUND: Patient-reported outcomes (PROs) are gaining an important role in the assessment of quality of care. There are currently limited data on the effect of payer type on PROs in total joint arthroplasty (TJA). This study compared both disease-specific and general health PROs among patients stratified according to their payer type. METHODS: Our institutional joint registry was queried for patients who underwent primary, elective, and unilateral hip and knee arthroplasty. Patients were divided according to their insurance type at the time of surgery into 3 groups: Medicaid, Medicare, or commercial. The outcomes assessed were the net changes in PROs as well as absolute scores at 6 months and 1 year. Six of the most commonly used PROs were assessed: Short Form-12 physical and mental components, Western Ontario and McMaster Universities Osteoarthritis Index, Single Assessment Numerical Evaluation, University of Californian Los Angeles activity level rating, and Oxford Hip Score. Analysis of variance and covariance were used. RESULTS: We evaluated 756 procedures (273 Medicaid, 270 Medicare, and 213 commercial insurance). Medicaid patients had significantly lower mean baseline scores across all PROs compared to either Medicare or commercial insurance patients. Medicaid patients were also more likely to be smokers, live alone, have lower educational level, African-American, and have nonprimary osteoarthritis as the indication for TJA. At 1-year follow-up, the net mean outcome gains were comparable among the 3 payer types (P > .05), but Medicaid patients continued to score lower while Medicare and commercial insurance patients continued to score higher (P < .01). When adjusting for all baseline differences among Medicaid patients, the negative effects of payer type resolved except for Oxford Hip Score which remained lower in the Medicaid group (P = .006). CONCLUSION: When using PROs to assess the value of care, the preoperative to postoperative changes are a better indicator of surgical success than comparing absolute values, especially in Medicaid patients. While TJA imparts similar net improvements to patients of all payer types, Medicaid coverage is a predictor of lower absolute outcome scores at any given time as result of increased baseline health burden (eg, depression, tobacco smoking, and poor overall well-being). Arthroplasty surgeons should be aware of these factors when counseling patients and seek optimization when necessary. The findings should be taken into account by stakeholders when constructing value-based payment models. Further research is needed to better understand the barriers leading to higher prevalence of increased health disparities among Medicaid beneficiaries and how to effectively address them.

Disparities in Total Hip Arthroplasty Outcomes: Census Tract Data Show Interactions Between Race and Community Deprivation.

INTRODUCTION: Socioeconomic factors such as poverty may mediate racial disparities in health outcomes after total hip arthroplasty (THA) and confound analyses of differences between blacks and whites. METHODS: Using a large institutional THA registry, we built models incorporating individual and census tract data and analyzed interactions between race and percent of population with Medicaid coverage and its association with 2-year patient-reported outcomes. RESULTS: Black patients undergoing THA had worse baseline and 2-year pain and function scores compared with whites. We observed strong positive correlations between census tract Medicaid coverage and percent living below poverty (rho = 0.69; P < 0.001). Disparities in 2-year Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function were magnified in communities with high census tract Medicaid coverage. For blacks in these communities, 2-year WOMAC function scores were predicted to be -5.54 points lower (80.42 versus 85.96) compared with blacks in less deprived communities, a difference not observed among whites. CONCLUSION: WOMAC pain and function 2 years after THA are similar among blacks and whites in communities with little deprivation (low percent census tract Medicaid coverage). WOMAC function at 2 years is worse among blacks in areas of higher deprivation but is not seen among whites. LEVEL OF EVIDENCE: Level II - Cohort Study.

Simplified Chinese version of hip and knee replacement expectations surveys in patients with osteoarthritis and ankylosing spondylitis: cross-cultural adaptation, validation and reliability.

BACKGROUND: The Hospital for Special Surgery Hip Replacement Expectations Survey (HSS-THRES) and Knee Replacement Expectations Survey (HSS-TKRES) are widely used tools developed to assess patients' preoperative expectations for total hip and knee arthroplasty. This study aimed to translate and adapt the HSS-THRES and HSS-TKRES into Chinese versions (SC-THRES/TKRES) and evaluate their psychometric properties in patients with osteoarthritis (OA) and ankylosing spondylitis (AS). METHODS: Patients scheduled for total hip (104 hip OA and 51 AS) or knee replacements (101 knee OA) were recruited in this study. Confirmatory Factor Analysis (CFA) was used to evaluate structural validity. The internal consistency was assessed by the Cronbach's α coefficient. The intraclass correlation coefficient (ICC) was used to assess test-retest reliability. The construct validity was analyzed by evaluating the correlations between SC-THRES/TKRES and the Expectation WOMAC. The correlations with the Expectation WOMAC were tested against our hypotheses. We additionally compared preoperative expectations of AS patients to those of hip OA patients. RESULTS: The results of CFA for the SC-THRES and SC-TKRES demonstrated good fit. The results for the SC-THRES/TKRES revealed good test-retest reliability and good internal consistency (AS: ICC = 0.893, Cronbach's α = 0.815; hip OA: ICC = 0.878, Cronbach's α = 0.814; knee OA: ICC = 0.806, Cronbach's α = 0.808). The correlations between the SC-THRES/TKRES and the Expectation WOMAC were moderate (0.541 for AS, 0.490 for hip OA and 0.465 for knee OA), which were consistent with the hypotheses. CONCLUSION: The SC-THRES/TKRES are reliable, valid for the evaluation of Chinese patients with OA and AS undergoing total hip and knee arthroplasty. The surveys can be used as part of preoperative assessments. Meanwhile, additional research is needed to replicate these findings and to assess the content validity in a larger sample.

Association between general joint hypermobility and knee, hip, and lumbar spine osteoarthritis by race: a cross-sectional study.

BACKGROUND: Osteoarthritis (OA) prevalence differs by race. General joint hypermobility (GJH) may be associated with OA, but differences by race are not known. This community-based study examined the frequency of GJH and its relationship with knee, hip, and lumbar spine OA by race (African American vs. Caucasian). METHODS: Data were from the Johnston County OA project, collected 2003-2010. GJH was defined as Beighton score ≥4. OA symptoms were defined as the presence of pain, aching, or stiffness on most days separately at the knee, hip, and lower back. Radiographic OA (rOA) of the knee or hip was defined as Kellgren-Lawrence grade 2-4. Lumbar spine rOA was disc space narrowing grade ≥1 and osteophyte grade ≥2 in ≥ 1 at the same lumbar level. Lumbar spine facet rOA was present in ≥ 1 lumbar levels. Separate logistic regression models stratified by race were used to examine the association between hypermobility and rOA or OA symptoms at each joint site, adjusting for age, sex, previous joint injury, and body mass index (BMI). RESULTS: Of 1987 participants, 1/3 were African-American and 2/3 were women (mean age 65 years, mean BMI 31 kg/m2). Nearly 8% of Caucasians were hypermobile vs. 5% of African-Americans (p = 0.03). Hypermobility was associated with lower back symptoms in Caucasians (adjusted odds ratio (aOR) 1.54, 95% confidence interval (CI) 1.00, 2.39), but not in African-Americans (aOR 0.77, 95% CI 0.34, 1.72). Associations between hypermobility and other knee, hip, or lumbar spine/facet OA variables were not statistically significant. CONCLUSIONS: General joint hypermobility was more common in Caucasians than African-Americans. Although there were no associations between hypermobility and rOA, the association between hypermobility and lower back symptoms may differ by race.

Genetic variation of SMAD3 is associated with hip osteoarthritis in a Chinese Han population.

Objective This study was performed to investigate the association between genetic variation in SMAD3 and hip osteoarthritis (OA) in a Chinese Han population. Methods The frequency of two single nucleotide polymorphisms of SMAD3, rs1470002 and rs12901499, was examined in 500 patients with hip OA and 1080 healthy controls in a Chinese Han population. Further analysis was performed according to sex and age. Results We detected statistically significant differences in the allele frequency and genotype between the hip OA and healthy control groups. The frequency of the GA+GG and GA genotypes of rs12901499 and the G variant were much higher in patients with hip OA than in healthy controls. This association was also present when the participants were stratified by sex and age. However, there was no significant association between the risk of hip OA and the presence of rs1470002 GA, AA, or GA+AA genotypes, even after sex- and age-stratified analysis. Conclusions The SMAD3 SNP rs12901499 GA genotype and G variant may increase the risk of hip OA in Chinese Han patients.

Hip-spine syndrome: A cadaveric analysis between osteoarthritis of the lumbar spine and hip joints.

BACKGROUND: Authors have recently proposed the concept of "hip-spine syndrome", however there exists limited evidence available to differentiate whether these concomitant arthritides are due to anatomic/structural causes, or systemic/metabolic effects. Exploring this relationship has important implications during the evaluation and treatment of both spine and hip disorders-a common clinical presentation of many patients. The purpose of this experiment was to investigate the individual contribution of hip arthritis towards the development of spine arthritis, with knee arthritis also being analyzed as a negative (systemic) control. HYPOTHESIS: Hip and spine arthritis are caused by both metabolic and anatomic causes. METHODS: A large, well-organized osteological database was queried, and osteoarthritis of the spine, hip, and knee joints was quantified using a validated scoring criteria. Six hundred and twenty-five specimens were chosen for analysis. Multivariate linear regression models were created to quantify the independent contributions of age, gender, race, height, and arthritis of the spine and hip joints. RESULTS: Age was the strongest predictor of arthritis at each site (standardized betas>0.281, P<0.001 for all). Hip arthritis was a stronger predictor of spine arthritis than was knee arthritis (standardized betas 0.215 and 0.155, respectively, P<0.001 for both). Spine arthritis was also a stronger predictor of hip arthritis than was knee arthritis (standardized betas 0.232 and 0.173, P<0.001 for both). CONCLUSIONS: Anatomic/structural influences about the lumbosacral-pelvic junction contribute towards the development of arthritis that is separate from any systemic/metabolic effects. Surgeons performing total hip arthroplasty should remain aware of these relationships, although future research is necessary regarding optimal surgical treatment of these patients. LEVEL OF EVIDENCE: N/A (cadaveric study).

Cross-Cultural and Construct Validity of the Animated Activity Questionnaire.

OBJECTIVE: The Animated Activity Questionnaire (AAQ) assesses activity limitations in patients with hip/knee osteoarthritis and consists of video animations; the patients choose the animation that best matches their own performance. The AAQ has shown good validity and reliability. This study aims to evaluate cross-cultural and construct validity of the AAQ. METHODS: Cross-cultural validity was assessed using ordinal logistic regression analysis to evaluate differential item functioning (DIF) across 7 languages. Construct validity was assessed by testing correlations between the AAQ and a patient-reported outcome measure (PROM) and performance-based tests. RESULTS: Data from 1,239 patients were available. Compared to the Dutch language (n = 279), none of the 17 items showed DIF in English (n = 202) or French (n = 193), 1 item showed uniform DIF in Spanish (n = 99) and Norwegian (n = 62), and 2 items showed uniform DIF in Danish (n = 201). In all these languages, the occurrence of DIF did not influence the total score, which remained comparable with the original Dutch version. For Italian (n = 203) versus Dutch, however, 6 items showed uniform DIF, and 1 item showed nonuniform DIF, indicating some problems with the cross-cultural validity between these countries. With regard to construct validity, the correlations with PROM (0.74) and performance-based tests (0.36-0.68) were partly as expected (>0.60). CONCLUSION: The AAQ, an innovative tool to measure activity limitations that can be placed on the continuum between PROMs and performance-based tests, showed a good overall cross-cultural validity, and seems to have great potential for international use in research and daily clinical practice in many European countries.

Racial Differences in Serum Adipokine and Insulin Levels in a Matched Osteoarthritis Sample: A Pilot Study.

BACKGROUND: In an attempt to correlate biomarkers with disease, serum-based biomarkers often are compared between individuals with osteoarthritis (OA) and control subjects. However, variable results have been reported. Some studies have suggested an association between certain adipokines and insulin and OA. We know that there are racial differences in OA prevalence and incidence, and from general population-based studies, those of Asian race consistently demonstrate a unique adipokine/insulin serum concentration profile as compared to Caucasians. Whether similar racial differences exist within OA samples is unknown and may have implications for selecting appropriate controls in comparative studies. METHODS: Serum levels of adipokines, leptin, and adiponectin, along with insulin, were determined by ELISA in patients scheduled for total hip or knee replacement surgery for OA. Fifteen Asian patients were matched 1 : 1 on age (±2 years), gender, body mass index (±1.5 kg/m(2)), and surgical joint with Caucasian patients. Differences in serum concentrations were tested using paired t-tests. RESULTS: Serum leptin and insulin levels were significantly higher in Asians compared to Caucasians (p < 0.05). While serum adiponectin levels were lower among Asians, the difference did not reach statistical significance (p = 0.12). CONCLUSION: Findings from this work suggest that when studying serum biomarker concentrations in OA versus controls, race may be an important factor to consider. Our findings warrant confirmation in larger studies.

The impact of arthritis on the physical function of a rural Maya-Yucateco community and factors associated with its prevalence: a cross sectional, community-based study.

This study aims to evaluate the impact of arthritis on the physical function of people living in a Maya-Yucateco rural community and to assess the association of known modifiable risk factors with the prevalence of overall arthritis and its main types (osteoarthritis and rheumatoid arthritis). Using a cross-sectional, community-based census design, data collected from the adult population (≥18 years) of the Municipality of Chankom, Yucatán, México, were analyzed (n = 1523). Participants' physical function was assessed using a culturized version of the health assessment questionnaire disability index. Social, physical, and behavioral factors linked to overall arthritis, osteoarthritis, and rheumatoid arthritis, were assessed through the "Community-Oriented-Program-for-the-Control-of-Rheumatic-Diseases [COPCORD]" questionnaire. A physiatrist and a rheumatologist confirmed all osteoarthritis and rheumatoid arthritis cases using the American College of Rheumatology criteria. Arthritis was confirmed in 169 cases (22 %, 95 % confidence interval (CI) 19-25) of those assessed for musculoskeletal symptoms (n = 779): osteoarthritis = 144, rheumatoid arthritis = 17, and non-specific arthritis = 8. Arthritis was associated with a higher prevalence of disability after controlling for age, gender, and number of comorbidities (odds ratio = 4.0, 95 % CI 3.0-6.0). Higher level of wealth was associated with lower arthritis prevalence (odds ratio = 0.9, 95% CI 0.8-0.9). Higher body mass index was associated with higher hip and/or knee osteoarthritis prevalence (odds ratio = 1.1, 95 % CI 1.03-1.1). Arthritis is highly associated with disability in the Mayan people living in Chankom. The prevalence of arthritis in Chankom is associated with social factors, such as people's level of wealth, while the prevalence of low-extremity osteoarthritis is associated with people's body mass index.

Measures of hip morphology are related to development of worsening radiographic hip osteoarthritis over 6 to 13 year follow-up: the Johnston County Osteoarthritis Project.

OBJECTIVES: We sought to describe the effect of alterations in hip morphology with respect to worsening hip OA in a community-based sample including African American (AA) and white men and women. METHODS: This nested case-control study defined case hips as Kellgren Lawrence grade (KLG) <3 on baseline supine pelvis radiographs and KLG ≥3 or THR for OA at the 1st or 2nd follow-up visit (mean 6 and 13 years, respectively); control hips had KLG <3 at both visits, with gender/race distribution similar to cases. Hip morphology was assessed using HipMorf software (Oxford, UK). Descriptive means and standard errors were obtained from generalized estimating equation (GEE) models. Sex-stratified GEE regression models (accounting for within-person correlation), adjusted for age, race, BMI, and side were then employed. RESULTS: A total of 120 individuals (239 hips; 71 case/168 control) were included (25% male, 26% AA, mean age 62 years, BMI 30 kg/m(2)). Case hips tended to have greater baseline AP alpha angles, smaller minimum joint space width (mJSW) and more frequent triangular index signs. Adjusted results among men revealed that higher AP alpha angle, Gosvig ratio, and acetabular index were positively associated with case hips; coxa profunda was negatively associated. Among women, greater AP alpha angle, smaller mJSW, protrusio acetabuli, and triangular index sign were associated with case hips. CONCLUSIONS: We confirmed an increased risk of worsening hip OA due to baseline features of cam deformity among men and women, as well as protrusio acetabuli among women, and provide the first estimates of these measures in AAs.

Novel statistical methodology reveals that hip shape is associated with incident radiographic hip osteoarthritis among African American women.

INTRODUCTION: Hip shape is a risk factor for the development of hip osteoarthritis (OA), and current methods to assess hip shape from radiographs are limited; therefore this study explored current and novel methods to assess hip shape. METHODS: Data from a prior case-control study nested in the Johnston County OA Project were used, including 382 hips (from 342 individuals). Hips were classified by radiographic hip OA (RHOA) status as RHOA cases (baseline Kellgren Lawrence grade [KLG] 0 or 1, follow-up [mean 6 years] KLG ≥ 2) or controls (KLG = 0 or 1 at both baseline and follow-up). Proximal femur shape was assessed using a 60-point model as previously described. The current analysis explored commonly used principal component analysis (PCA), as well as novel statistical methodologies suited to high dimension low sample size settings (Distance Weighted Discrimination [DWD] and Distance Projection Permutation [DiProPerm] hypothesis testing) to assess differences between cases and controls. RESULTS: Using these novel methodologies, we were able to better characterize morphologic differences by sex and race. In particular, the proximal femurs of African American women demonstrated significantly different shapes between cases and controls, implying an important role for sex and race in the development of RHOA. Notably, discrimination was improved with the use of DWD and DiProPerm compared to PCA. CONCLUSIONS: DWD with DiProPerm significance testing provides improved discrimination of variation in hip morphology between groups, and enables subgroup analyses even under small sample sizes.

Racial differences in associations between baseline patterns of radiographic osteoarthritis and multiple definitions of progression of hip osteoarthritis: the Johnston County Osteoarthritis Project.

BACKGROUND: To identify baseline radiographic features that predict hip osteoarthritis (HOA) progression, and to explore differences in these associations by race. METHODS: Radiographs from the community-based Johnston County OA Project were scored using Kellgren-Lawrence (KL) grade and for presence and location of joint space narrowing (JSN), osteophytes, and subchondral changes. Associations between these features and HOA progression (increase of at least 1 KL grade, interval hip replacement, range of motion [ROM, a reduction of ≥10° in internal rotation], or disability [increase of ≥0.2 in Health Assessment Questionnaire scores], or Any of these) were assessed using logistic regression, adjusting for age, gender, race, hip injury, BMI, education, smoking and follow-up time, accounting for multiple comparisons. Race interactions were assessed and analyses stratified as indicated. RESULTS: The sample (n = 1,422) included 40 % men and 26 % African American (AA) participants, with mean age 61 years and BMI 29 kg/m(2). The baseline frequency of radiographic hip OA (RHOA) between Caucasians and AAs was similar (23 %), although some radiographic features differed. AAs were more likely to have progression defined by ROM or disability or Any progression; Caucasians were more likely to have RHOA progression. JSN, subchondral sclerosis, and medial osteophytes were associated with increased RHOA progression overall; JSN was associated with disability progression only in AAs, while lateral osteophytes were associated with ROM progression only in Caucasians. CONCLUSIONS: AAs and Caucasians exhibited differences in the radiographic presentation and progression patterns of HOA, with AAs reporting progressive pain and disability, while Caucasians had more RHOA progression.

Four-year results of Summit stems for total hip arthroplasty in Japanese patients.

PURPOSE: A retrospective study to evaluate the clinical and radiographic outcome of the Summit primary total hip arthroplasty (THA) at a minimum follow-up of 4 years. METHODS: 87 hips in 84 Japanese patients underwent THA using Summit stems. 3 patients were lost to follow-up, and 4 patients were excluded because a Summit stem was judged to be inappropriate for their narrow femoral canals. The remaining 80 hips in 77 patients were evaluated. Mean age was 66 years (range, 33-86 y). Mean postoperative follow-up period was 52 months (range, 48-66 m). RESULTS: There was no early stem subsidence after surgery. Of the 80 hips, 60 (75%) showed radiographic signs of stem osseointegration including zones 3 and 5 at final follow-up. Stress shielding occurred in 50 hips (62.5%), and third-degree stress shielding was observed in 12 hips (15%). 3 patients experienced postoperative thigh pain due to distal fixation. CONCLUSIONS: These short-term results indicate that the Summit stem achieved good initial fixation, although there were some cases of distal fixation. Careful long-term follow-up and observation will be necessary for hips in which stress shielding occurs.