Risk Factors For Hip Osteoarthritis Research Articles

A Study on Imaging Risk Factors for Hip Osteoarthritis.

Due to low prevalence and few studies, the morphologic risk factors for hip osteoarthritis (HOA) in Chinese population remain unknown. The purpose of this study was to investigate the relationship between 10 radiographic parameters measured via anteroposterior pelvic X-ray radiography and HOA in Chinese population. Thirty-three patients who required total hip arthroplasty for unilateral HOA (2017-2022) and 132 healthy individuals were selected for this case-control study. We measured 10 radiological parameters via anteroposterior pelvic X-ray radiography, which were sharp angle, center edge angle, sourcil angle, neck shaft angle, α angle, pelvic height, pelvic width, femoral head diameter, femoral neck width, and ratio of the femoral head diameter to the femoral neck width. After measurements were obtained, logistic regression analysis was utilized to calculate the adjusted odds ratios (ORs) for confounding variables such as age, sex, and body mass index (BMI). Receiver operating characteristic (ROC) curves were utilized to determine the proportional risk contribution (PRC) of each radiographic factor. After adjustment for confounding factors, individuals with a larger sourcil angle (SA) (OR = 4.89, 95% CI 1.66-14.42, p = 0.004), larger α angle (OR = 4.14, 95% CI 1.53-11.23, p = 0.005), and wider femoral neck (OR = 5.27, 95% CI 1.50-18.51, p = 0.01) were found to have a greater risk of developing HOA. Among all radiographic parameters, the SA demonstrated the greatest risk contribution (PRC = 13.695%). Radiographic parameters correlate with the incidence of HOA. The SA is probably the most powerful of all the parameters related to HOA.

Risk factors for hip osteoarthritis after arthroscopy in patients with femoroacetabular impingement

To investigate the risk factors of hip osteoarthritis（HOA） after hip arthroscopy in patients with femoro-acetabular impingement（FAI） syndrome, and to reduce and prevent HOA. From September 2018 to September 2020, 106 patients with FAI underwent hip arthroscopy, including 40 males and 66 females, aged from 20 to 55 years old with an average age of （33.05±10.19） years old. The mechanism of injury included 51 cases for sports injury, 36 for traffic accidents, and 19 for blunt object injury. The duration of the disease ranged from 5 to 19 days with an average of （12.02±3.69） days. All patients were followed up for 18 months. Patients were divided into HOA group （23 cases） and non-HOA group （83 cases） according to the occurrence of HOA. Multivariate Logistic regression was used to analyze the risk factors of HOA after hip arthroscopy in FAI patients. By univariate analysis, aged from 50 to 70 years old, female, body mass index（BMI）> 30 kg·m-2, physical labor, cam type, postoperative infection, last follow-up hip degree of motion （range of motion, ROM） （flexion, abduction, adduction, internal rotation） and Tönnis grade 1 and above of the HOA group were higher than those of the non-HOA group （P<0.05）, and the relative appendicular skeletal muscle index （RASM） was lower than that of non-HOA group（P<0.05）. By multiple Logistic regression analysis, cam type, BMI>30 kg·m-2, last follow-up hip internal rotation ROM and Tönnis grade 1 were risk factors for HOA after hip arthroscopy in FAI patients （P<0.05）. FAI classification, body mass index, hip ROM and Tönnis grade are all related to HOA after hip arthroscopy in FAI patients. Follow-up and intervention should be strengthened in high-risk FAI patients to reduce the occurrence of HOA.

Application of deep learning for automated diagnosis and classification of hip dysplasia on plain radiographs

BackgroundHip dysplasia is a condition where the acetabulum is too shallow to support the femoral head and is commonly considered a risk factor for hip osteoarthritis. The objective of this study was to develop a deep learning model to diagnose hip dysplasia from plain radiographs and classify dysplastic hips based on their severity.MethodsWe collected pelvic radiographs of 571 patients from two single-center cohorts and one multicenter cohort. The radiographs were split in half to create hip radiographs (n = 1022). One orthopaedic surgeon and one resident assessed the radiographs for hip dysplasia on either side. We used the center edge (CE) angle as the primary diagnostic criteria. Hips with a CE angle < 20°, 20° to 25°, and > 25° were labeled as dysplastic, borderline, and normal, respectively. The dysplastic hips were also classified with both Crowe and Hartofilakidis classification of dysplasia. The dataset was divided into train, validation, and test subsets using 80:10:10 split-ratio that were used to train two deep learning models to classify images into normal, borderline and (1) Crowe grade 1–4 or (2) Hartofilakidis grade 1–3. A pre-trained on Imagenet VGG16 convolutional neural network (CNN) was utilized by performing layer-wise fine-turning.ResultsBoth models struggled with distinguishing between normal and borderline hips. However, achieved high accuracy (Model 1: 92.2% and Model 2: 83.3%) in distinguishing between normal/borderline vs. dysplastic hips. The overall accuracy of Model 1 was 68% and for Model 2 73.5%. Most misclassifications for the Crowe and Hartofilakidis classifications were +/- 1 class from the correct class.ConclusionsThis pilot study shows promising results that a deep learning model distinguish between normal and dysplastic hips with high accuracy. Future research and external validation are warranted regarding the ability of deep learning models to perform complex tasks such as identifying and classifying disorders using plain radiographs.Level of EvidenceDiagnostic level IV

Comparison between UK Biobank and Shanghai Changfeng suggests distinct hip morphology may contribute to ethnic differences in the prevalence of hip osteoarthritis

ObjectsJoint morphology is a risk factor for hip osteoarthritis (HOA) and could explain ethnic differences in HOA prevalence. Therefore, we aimed to compare the prevalence of radiographic HOA (rHOA) and hip morphology between the predominantly White UK Biobank (UKB) and exclusively Chinese Shanghai Changfeng (SC) cohorts. MethodsLeft hip iDXA scans were used to quantify rHOA, from a combination of osteophytes (grade>1) and joint space narrowing (grade>1), and hip morphology. Using an 85-point Statistical Shape Model (SSM) we evaluated cam (alpha angle (AA) ≥60°) and pincer (lateral centre edge angle (LCEA) ≥45°) morphology and acetabular dysplasia (LCEA <25°). Diameter of the femoral head (DFH), femoral neck width (FNW) and hip axis length (HAL) were also obtained from these points. Results were adjusted for differences in age, height and weight and stratified by sex. ResultsComplete data were available for 5,924 SC and 39,020 White UKB participants with mean ages of 63.4 and 63.7 years old. rHOA prevalence was considerably lower in female (2.2% versus 13.1%) and male (12.0% and 25.1%) SC compared to UKB participants. Cam morphology, rarely seen in females, was less common in SC compared with UKB males (6.3% versus 16.5%). Composite SSM modes, scaled to the same overall size, revealed SC participants to have a wider femoral head compared to UKB participants. FNW and HAL were smaller in SC compared to UKB, whereas DFH/FNW ratio was higher in SC. ConclusionsrHOA prevalence is lower in Chinese compared with White individuals. Several differences in hip shape were observed, including frequency of cam morphology, FNW and DFH/FNW ratio. These characteristics have previously been identified as risk factors for HOA and may contribute to observed ethnic differences in HOA prevalence.

Increase in TPSB2 and TPSD1 Expression in Synovium of Hip Osteoarthritis Patients Who Are Overweight.

While research suggests that increasing body mass index (BMI) is a risk factor for hip osteoarthritis (HOA), the mechanisms of this effect are not fully understood. Tryptases are among the main proteases found in mast cells (MCs) and contribute to OA pathology. TPSB2, which encodes β-tryptase, is increased in the synovium of overweight and obese knee OA patients. However, it remains unclear whether tryptase in the synovium of HOA is increased with increasing BMI. Here, we investigated tryptase genes (TPSB2 and TPSD1) in the synovium of overweight HOA patients. Forty-six patients radiographically diagnosed with HOA were allocated to two groups based on BMI, namely normal (<25 kg/m2) and overweight (25-29.99 kg/m2). TPSB2 and TPSD1 expression in the synovium of the two groups was compared using real-time polymerase chain reaction. To compare TPSB2 and TPSD1 expression in MCs between the groups, we isolated the MC-rich fraction (MC-RF) and MC-poor fraction (MC-PF), extracted using magnetic isolation. TPSB2 and TPSD1 expression was increased in the overweight group compared with the normal group. Expression of both genes in the MC-RF was significantly higher than that in MC-PF in both groups. However, TPSB2 and TPSD1 expression levels in the MC-RF did not differ between the groups. Tryptase genes were highly expressed in the synovium of overweight HOA patients. Further investigation to reveal the role of tryptase in the relationship between increasing BMI and HOA pathology is required.

INCREASED RISK OF UNDERGOING HIP ARTHROPLASTY AT A YOUNGER AGE IN OBESE AUSTRALIANS

Obesity is a known risk factor for hip osteoarthritis. The aim of this study was to compare the incidence of obesity in Australians undergoing hip replacements (HR) for osteoarthritis to the general population.A cohort study was conducted comparing data from the Australian Bureau of Statistics and the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) from 2017-18. Body mass index (BMI) data for patients undergoing primary total hip replacement and resurfacing for osteoarthritis were obtained from the AOANJRR. The distribution of HR patients by BMI category was compared to the general population, in age and sex sub-groups.During the study period, 32,495 primary HR were performed for osteoarthritis in Australia. Compared to the general population, there was a higher incidence of Class I, II, and III obesity in patients undergoing HR in both sexes aged 35 to 74 years old. Class III obese females and males undergoing HR were on average 6 to 7 years younger than their normal weight counterparts. Class III obese females and males aged 55-64 years old were 2.9 and 1.7 times more likely to undergo HR, respectively (p&lt;0.001).There is a strong association between increased BMI and relative risk of undergoing HR. Similar findings have been noted in the United States of America, Canada, United Kingdom, Sweden and Spain. A New Zealand Registry study and recent meta-analysis have also found a concerning trend of Class III obese patients undergoing HR at a younger age.Obese Australians are at increased risk of undergoing HR at a younger age. A national approach to address the prevalence of obesity is needed.

AB1331 DIAGNOSTIC CAPABILITY OF ANESTHETIC INTRA-ARTICULAR INJECTIONS FOR FEMOROACETABULAR IMPINGEMENT

BackgroundFemoroacetabular impingement syndrome (FAIS) is a highly prevalent painful disorder that is considered a risk factor for hip osteoarthritis. Confirming that FAIS is the main cause of a pain is a hard task. There are patients who have the typical morphological alterations of FAIS, but are asymptomatic. FAIS morphologies can represent a major confounding factor in patients with undiagnosed rheumatic diseases. On the other hand, surgery can significantly improve quality of life of patients with FAIS. Anesthetic intra-articular injections might constitute viable alternatives for diagnosing FAIS.ObjectivesThis systematic review aimed to answer the following question: “What is the diagnostic capability of anesthetic intra-articular hip injections for the assessment of FAIS?”.MethodsThis study was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) statement. Embase, CINAHL, LILACS, PubMed, SCOPUS, SPORTDiscuss, The Cochrane Library, and Web of Science databases were screened. All studies that assessed the diagnostic capability of anesthetic intra-articular hip injections for the assessment of FAIS were considered eligible. Study selection and data collection were performed by three independent reviewers. Risk of bias of the included studies was assessed through the QUADAS-2 tool.ResultsA total of 13 articles were selected for full-text reading, of which 5 were finally considered eligible and included for analysis [1-5]. A summary of the studies’ descriptive characteristics can be found in the Table 1. Overall judgment was “at risk of bias” for all included studies (Figure 1). More detailed information regarding bias assessment at QUADAS-2 is available in the Figure 1. From 5 included studies, only 2 [2,5] indicated that anesthetic intra-articular injections can be useful as diagnostic tools for FAIS.Figure 1.Table 1.AuthorMean AgeN (Female)Injection ContentInjection GuidanceTime for pain assessment after injection (Way of assessment)Threshold to consider FAIS diagnosisReference StandardFindingsKivlan29.9 ± 10.472 (54)Lidocaine + bupivacaine + triamcinoloneFluoroscopy2 hours (provocative activities)Not establishedArthroscopyNo difference in pain relief after injection between individuals with and without FAIS (p=0.128)Kraeutler38.8 ± 14.2161 (120)Lidocaine + triamcinoloneNon-guided10 minutes (physical tests and provocative activities)&gt;70% of pain relief after injectionSymptoms + physical tests + radiographyFAIS and dysplasia diagnosed in 76% of patients with &gt;70% of pain relief after injection, and in 67% in patients presenting &lt;70% (p=0.62)Chinzei36.7 ± 14.749 (27)LidocaineFluoroscopy2 weeks (uninformed)&gt;50% of pain reliefArthroscopyNo significant association between pain relief intensity after injection and the presence of FAIS (p&gt;0.05)Gao36 (16-65)78 (41)Lidocaine + betamethasoneUltrasound10 minutes and 1 week (routine tasks)&gt; 50% of pain reliefArthroscopyResponse to injection is 91.7% accurate for detecting FAISPerdikakis33 (18-58)34 (20)RopivacaineFluoroscopy30 minutes (physical tests)UninformedArthroscopyResponse to injection presented 92% of PPV and 96,5% of accuracy for diagnosing FAIS, with NPV and sensitivity of 100%ConclusionEvidence regarding the diagnostic capability of anesthetic intra-articular hip injections for FAIS is sparse. In order to accurately answer our research question, future studies that use standardized and optimized protocols of injection and pain assessment after injection are still essential. Furthermore, the need to take into account the different biases surrounding diagnostic studies was highlighted in our study.

Hybrid Hyaluronic Acid versus High Molecular Weight Hyaluronic Acid for the Treatment of Hip Osteoarthritis in Overweight/Obese Patients.

Background: Obesity is the main risk factor for hip osteoarthritis, negatively affecting the outcome of the disease. We evaluated the effectiveness of viscosupplementation with hybrid hyaluronic acid compared to that with high molecular weight hyaluronic acid in overweight/obese patients with hip osteoarthritis (OA). Methods: 80 patients were divided into two groups: a treatment group received two ultrasound-guided intra-articular hip injections of hybrid HA 15 days apart; a control group received a single ultrasound-guided infiltration with medium-high molecular weight hyaluronic acid (1500–2000 kDa). We assessed the pain, functional and cardiovascular capacity of the patients at baseline, after 3 months, and after 6 months of the infiltrative sessions. Results: The treatment group showed greater improvements in the scores on the NRS scale (5.4 ± 0.8 vs. 6.3 ± 0.8; p < 0.05) and in the Lequesne index (11.4 ± 2.6 vs. 13.6 ± 2.7; p < 0.05) and in the distance traveled at 6MWT (238.1 ± 53.9 m vs. 210.7 ± 46.2 m; p = 0.02) both at 3 months (T1) and at 6 months (T2). Conclusions: This study underlines the importance of exploiting the anti-inflammatory, analgesic, and chondrogenic properties of hybrid HA for the treatment of hip OA in overweight/obese patients.

Risk factors for long-term hip osteoarthritis in patients with hip dysplasia without surgical intervention.

ABSTRACTHip dysplasia is a common cause of hip pain and a known risk factor for hip osteoarthritis (OA) and early total hip arthroplasty (THA). Unfortunately, little is known about the specific factors associated with an increased risk of OA. The purpose was (i) to report the overall rate of symptomatic hip OA and THA and (ii) to identify radiographic features and patient characteristics associated with the development of symptomatic hip OA. A geographic database was used to identify all patients aged 14–50 years old diagnosed with symptomatic hip dysplasia between 2000 and 2016. Kaplan–Meier analysis was used to determine the rate of symptomatic hip OA, defined as a Tönnis grade of ≥1 on hip radiograph. Univariate and multivariate proportional hazard regression models were performed to determine risk factors for OA. One hundred and fifty-nine hips (144 patients) with hip dysplasia (52 F:107 M) out of 1893 patients with hip pain were included. Of these, 45 (28%) had severe hip dysplasia with a lateral center-edge angle ≤18°. Mean age at time of presentation was 26.1 (±10.1) years. Mean follow-up time was 8.2 (±5) years. The rate of OA was 20%. THA was performed in 11% of patients. Body mass index >29 (P = 0.03) and increased age (P < 0.01) were risk factors for OA. Patients with symptomatic hip dysplasia are at significant risk of developing hip OA. Body mass index >29 and age ≥35 years at the time of presentation with hip pain were risk factors for hip OA.

The influence of adult hip shape genetic variants on adolescent hip shape: Findings from a population-based DXA study.

ObjectiveHip shape is a well-recognized risk factor for hip osteoarthritis (OA) and hip fracture. We aimed to investigate whether the genetic variants known to be associated with adult hip shape were also associated with adolescent hip shape.MethodsHip DXA scans, obtained in offspring from the Avon Longitudinal Study of Parents and Children (ALSPAC) at two time points (mean ages 13.8 and 17.8 years), were used to quantify hip morphology using a 53-point Statistical Shape Model (SSM). Principal component analysis was used to generate hip shape modes (HSMs). Genetic variants which had previously shown genome-wide significant association with specific HSMs in adults were tested for association with the same HSMs in adolescents (at each timepoint separately) using SNPTEST v2.ResultsComplete genotypic and phenotypic data were available for 3550 and 3175 individuals at 14 and 18 years, respectively. The strongest evidence for association with adolescent hip shape was for a variant located near SOX9 (rs2158915) with consistent effects across both time points for HSM1 (age 14: beta −0.05, p = 9.9 × 10−8; age 18: −0.05, p = 3.3 × 10−6) and HSM5 (age 14: beta −0.07, p = 1.6 × 10−4; age 18: −0.1, p = 2.7 × 10−6). There was also strong evidence of association between rs10743612 (near PTHLH) and HSM1 (age 14: 0.05, p = 1.1 × 10−5; age 18: 0.04, p = 0.003) and between rs6537291 (near HHIP) and HSM2 (age 14: −0.06, p = 0.001; age 18: −0.07, p = 0.001) across both time points. The genes with the strongest associations with hip shape in adolescents, (SOX9, PTHLH and HHIP) are known to be involved in endochondral bone formation. HSM1 indicates narrower aspect ratio of the upper femur, whereas both HSM2 and HSM5 reflect variation in the femoral head size and femoral neck width, features previously found to be related to the risk of OA in later life. The SOX9 locus has previously been found to associate with increased risk of hip fracture.ConclusionIn conclusion, variants implicated in endochondral bone formation appear to consistently influence hip shape between adolescence and adulthood, including those aspects related to risk of hip OA and/or fracture in later life.

Constitutional morphological features and risk of hip osteoarthritis: a case–control study using standard radiographs

ObjectivesTo evaluate the risk of association with hip osteoarthritis (OA) of 14 morphological features measured on standard antero-posterior pelvis radiographs.MethodsA case–control study of 566 symptomatic unilateral hip OA cases and...

Risk Factors for Long-term Hip Osteoarthritis in Patients With Femoroacetabular Impingement Without Surgical Intervention

Background: Femoroacetabular impingement (FAI) is a common cause of hip pain and a known risk factor for hip osteoarthritis (OA) and total hip arthroplasty (THA) at a young age. Unfortunately, little is known about the specific factors associated with an increased risk of OA. Purpose: To (1) report the overall rate of symptomatic hip OA and/or THA in patients with FAI without surgical intervention and (2) identify radiographic features and patient characteristics associated with hip OA. Study Design: Case-control study; Level of evidence, 3. Methods: A geographic database was used to identify all patients with hip pain and radiographs between 2000 and 2016. Chart review was performed to identify patients with FAI. Patient medical records were reviewed to obtain demographic information, clinical history, physical examination findings, imaging details, and treatment details. Kaplan-Meier analysis was used to determine the rate of hip OA. Univariate and multivariate proportional hazard regression models were performed to determine risk factors for OA. Results: The study included 952 patients (649 female; 303 male; 1104 total hips) with FAI. The majority of hips had mixed type (n = 785; 71.1%), 211 (19.1%) had pincer type, and 108 (9.8%) had cam type. Mean age at time of presentation was 27.6 ± 8.7 years. Mean follow-up time was 24.7 ± 12.5 years. The rate of OA was 13.5%. THA was performed in 4% of patients. Male sex, body mass index (BMI) greater than 29, and increased age were risk factors for OA (male sex: hazard ratio [HR], 2.28; P < .01; BMI >29: HR, 2.11; P < .01; per year of increased age: HR, 1.11; P < .01.). Smoking and diabetes mellitus were not significant risk factors. No radiographic morphological features were found to be significant risk factors for OA. Conclusion: At mean follow-up of 24.7 years, 14% of hips had symptomatic OA and 4% underwent THA. BMI greater than 29, male sex, and increased age at the time of presentation with hip pain were risk factors for hip OA. The cohort consisted of a large percentage of mixed-type FAI morphologies, and no specific radiographic risk factors for OA were identified.

Collagen IX deficiency leads to premature vascularization and ossification of murine femoral heads through an imbalance of pro- and antiangiogenic factors

The vascular invasion of cartilage is an essential process in the endochondral ossification of long bones. In contrast, vascularization of articular cartilage constitutes a pathological mechanism in the development of osteoarthritis. Polymorphisms of Col9a1 have been described as risk factors for hip osteoarthritis (OA) and the loss of collagen IX is known to lead to premature OA of the hip joint in mice but the underlying mechanism is so far unknown. To understand the contribution of collagen IX to OA development in the hip joint, we analyzed the early development of murine Col9a1-/- femoral heads between newborn stage and 16 weeks of age. We found significantly accelerated ossification of the femoral heads in the absence of collagen IX as well as premature vascular and osteoclast invasion, even though hypertrophic differentiation was delayed. The loss of collagen IX led to anatomically altered femoral heads lacking the epiphyseal tubercle. Interestingly, this region was found to contain highest levels of the antiangiogenic protein thrombospondin-1 (TSP-1). Hence, TSP-1 levels were strongly reduced in the Col9a1-/- femoral heads. In addition, antiangiogenic matrilin-1 was found to be decreased, while proangiogenic active MMP-9 levels were increased in the collagen IX deficient mice compared to wildtype controls. We conclude that collagen IX protects against premature vascularization and cartilage to bone transition in femoral heads by increasing the levels of antiangiogenic TSP-1 and matrilin-1 and decreasing the levels of proangiogenic active MMP-9.

Mendelian randomization identifies a causal role for serum insulin-like growth factor-1 in hip osteoarthritis

Purpose: Individuals with acromegaly (characterised by elevated circulating IGF-1) are at an increased risk of secondary osteoarthritis (OA), but epidemiological evidence for an association between serum insulin-like growth factor-1 (IGF-1) and OA in the general population is conflicting. We determined the observational associations between serum IGF-1 and hospital-diagnosed (HD) hand, hip and knee and hand OA in UK Biobank (UKBB). We performed Mendelian Randomization (MR) to determine if observed associations represent a true causal effect. Methods: Serum IGF-1 was assessed by chemiluminescent immunoassay. HD hip, knee and hand OA were determined using linked hospital inpatient records. Observational associations between serum IGF-1 and HD OA variables were determined by multivariable logistic regression, adjusting for age, sex, ethnicity, oestrogen use and BMI. We performed one-sample (1SMR) using two-stage least-squares regression, with an unweighted allele score generated from the eight single nucleotide polymorphisms (SNPs) robustly associated with IGF-1 in the largest genome-wide association study (GWAS) meta-analysis, as an instrument. MR is a form of instrumental variable regression which uses genetic variants robustly related to the exposure as instruments, providing an estimate of the causal effect which is unbiased by confounding and reverse causality. Multivariable MR (MVMR) determined the BMI-independent effect of IGF-1, by including BMI as an additional exposure, instrumented by an unweighted BMI allele score generated from 69 independent loci. MR analyses were adjusted for sex, genotyping chip and 10 principal components (PCs) to account for population stratification. Results: 421,572 individuals had complete data for the observational analyses, of whom 332,092 (79%) had genetic data, were unrelated and of European ancestry, suitable for MR. The mean (SD) ages of the observational and MR populations were 56.4 (8.1) and 56.5 (8.0) years respectively, with 54% female in both populations. Median (interquartile range) IGF-1 concentration was 21.3 (17.6, 24.9) nmol/L in both populations. In the observational population, 3.1% had HD hip OA (3.2% in the MR population); 0.7% had hand OA and 5.4% knee OA in both populations. In analyses adjusted for age, sex, ethnicity and oestrogen use, serum IGF-1 concentration was associated with a decreased odds of HD OA (ORhand=0.82 [0.77, 0.88] p=3x10-9, ORhip=0.94 [0.91, 0.97] p=4x10-4, ORknee=0.81 [0.80, 0.83] p=1x10-64; OR per doubling in IGF-1 concentration). After additional adjustment for BMI, serum IGF-1 remained associated with a reduced odds of hand OA; however, it was then associated with an increased odds of hip OA (ORhip=1.04 [1.01, 1.07] p=0.014), with little evidence of an association with knee OA. Using 1SMR, we found strong evidence for increased risk of hip OA with higher IGF-1 concentrations (risk difference per SD increase in IGF-1=0.009 [0.004, 0.015] p=0.001, corresponding to an approximate ORhip 1.36 [1.13, 1.63]), and also evidence for an increased risk of knee OA (risk difference=0.009 [0.001, 0.016] p=0.019). In contrast, point estimates suggested a decreased risk of hand OA, although confidence intervals were wide, reflecting the low prevalence of HD hand OA. When testing the assumptions of MR, we found evidence for an association between the IGF-1 allele score and BMI, which violates the assumption that an instrument is unrelated to any confounders of the exposure-outcome relationship. We therefore performed MVMR analyses to determine the BMI-independent effect; the effect size for IGF-1 on hip OA was unchanged (risk difference=0.009 [0.003, 0.014] p=0.003); whereas, the effect of IGF-1 on knee OA was attenuated by one-third (risk difference=0.006 [-0.001, 0.014] p=0.076). Conclusions: Our MR analyses provide strong evidence that higher concentrations of serum IGF-1 are a causal risk factor for hip OA in a very large UK population, with weaker evidence for a causal role in knee OA and very little evidence for an effect on hand OA. Our MVMR analyses estimate the direct effect of IGF-1 on OA conditional on BMI, these results suggest that this causal role of IGF-1 is independent of BMI, consistent with our observational analyses. Further study is justified to determine the mechanism underlying this association.

Is lesser trochanter size a novel risk factor for hip osteoarthritis? findings from the MROS study

Purpose: Previously, we used statistical shape modelling (SSM) of hip dual x-ray absorptiometry (DXA) scans to examine associations between two-dimensional (2D) whole hip shape and radiographic hip osteoarthritis (rHOA). A limitation in this approach is that it is difficult to know precisely which aspects of shape underlie the relationships we observed. We aimed to define which shape characteristics are related to rHOA in more detail, by examining individual subregions of the hip, and utilising three-dimensional (3D) hip shape derived from quantitative computed tomography (QCT) scans to validate our findings.

Quality of life trajectories differ across patients with femoral acetabular impingement and increasing hip osteoarthritis severity 24 months after hip arthroscopic surgery

Purpose: Femoral acetabular impingement is a proliferative musculoskeletal diagnosis among young-to-middle aged adults and proposed to be a significant risk factor for hip osteoarthritis. Arthroscopic surgery is a recommended treatment intended to decrease symptoms, restore joint mechanics and disrupt further articular cartilage damage, yet inconsistent evidence exists, and little is known about postoperative quality of life trajectories and its relationship with osteoarthritis severity. The purpose of this study was to investigate the quality of life trajectories from preoperative to 24-month postoperative hip arthroscopic surgery in patients with and without hip osteoarthritis.

Radiographic factors associated with hip osteoarthritis: a systematic review.

The purpose of this study was to outline factors that contribute to the appearance of hip osteoarthritis (OA). Secondarily, this study aims to describe radiographic factors that are associated with the progression of OA in the arthritic hip. Pubmed/MEDLINE and Embase were searched in November 2018 for radiographic risk factors for hip OA. All articles were eligible if they (i) were written in the English language and (ii) commented on OA as it relates to radiographic description, appearance or progression of OA. Demographic characteristics of the study cohort, definition of OA, baseline OA and factors for prediction or progression of OA were recorded. Nine articles were included in this review. A total of 3268 patients were analyzed across all studies. The mean age was 60.0 years (range 18–91.5). The most common descriptors for OA were dysplasia and cam impingement. Six of the nine articles found acetabular under-coverage to be associated with developing OA. Four articles found cam morphology to be an associated factor. Finally, four articles commented on the factors associated with the progression to more severe grades of OA, reporting exclusively on acetabular under-coverage, whereas only one reported on cam morphology to be associated. This systematic review found acetabular under-coverage followed by cam morphology to be strongly associated with both the development and progression of hip OA. These findings define patients at risk for developing hip OA and emphasize the importance of early awareness of future joint degeneration.

Relationship Between Hip Morphology and Hip‐Related Patient‐Reported Outcomes in Young and Middle‐Aged Individuals: A Population‐Based Study

ObjectiveRadiographic measurements of the alpha angle and the lateral center edge (LCE) angle in the hip joint are important for the diagnosis of femoroacetabular syndrome, a potential risk factor for hip osteoarthritis. Our objective was to determine whether these measurements are associated with hip‐related patient‐reported outcomes in young and middle‐aged individuals.MethodsA stratified random sample of white men and women ages 20–49 years, with and without hip pain, was selected using random digit dialing from the population of metro Vancouver, Canada. The alpha and LCE angles were measured bilaterally on radiographs using Dunn and anteroposterior views, respectively. Patient‐reported outcomes were measured by the Copenhagen Hip And Groin Outcome Score (HAGOS), which has scales for symptoms, pain, daily activities, sports, physical activity, and quality of life (QoL). We performed descriptive analyses and a regression analysis with restricted cubic splines, adjusted for age and sex and weighted for the sampling design.ResultsData were obtained for 500 subjects. The alpha angle distribution was strongly skewed, with a mean of 54°. The LCE angle distribution was symmetric, with a mean of 34°. In the restricted cubic splines analysis, the relationship between the alpha angle and HAGOS scores was nonlinear, with higher alpha angles generally associated with worse HAGOS scores for alpha >60°. The associations were statistically significant for symptoms, sports, and QoL. No association was found between the LCE angle and HAGOS scales.ConclusionIn a general population sample ages 20–49 years, we have found an association between the alpha angle and hip‐related patient‐reported outcomes.

Vascular cell adhesion molecule1 in patients with severe osteoarthritis of the hip : Aprospective cross-sectional study.

SummaryBackgroundOsteoarthritis (OA) of the hip is a frequent and debilitating joint disease. Only few clinical risk factors for hip OA are established and clinically applicable biomarkers to identify patients at risk are still lacking. The glycoprotein vascular cell adhesion molecule 1 (VCAM-1) is expressed by chondrocytes and synovial tissue and was a predictive marker for development of severe large joint OA in a previous study.ObjectiveIt was tested whether increased serum levels of VCAM-1 are prevalent in patients with severe OA of the hips.MethodsIn this prospective, multicenter, cross-sectional study, risk factors of severe hip OA were investigated in patients scheduled for hip joint arthroplasty and 100 patients were randomly selected for validation of VCAM-1 as a potential biomarker for hip OA. Serum samples were analyzed by an enzyme-linked immunosorbent assay and compared with a sex and age-matched control cohort.ResultsThe groups were similar in age, gender ratio and prevalence of diabetes. Serum concentrations of VCAM-1 were 8% higher in OA patients compared to controls, without reaching statistical significance (818 ng ml−1, 95% confidence interval, CI 746–891 ng ml−1 versus 759 ng m−1, 95% CI 711–807 ng ml−1; P = 0.4839).ConclusionThe results of this study show that serum concentrations of VCAM-1 cannot distinguish patients with severe hip OA from age and sex-matched controls.

Effect of contralateral cane use on hip moment impulse in the frontal plane during the stance phase

BackgroundRecent reports have shown that the daily cumulative moment in the frontal plane (i.e., product of hip moment impulse in the frontal plane during the stance phase and mean steps per day) is a risk factor for hip osteoarthritis. This study aimed to clarify the effect of contralateral cane use on hip moment impulse in the frontal plane of the stance limb. MethodsThis study included 15 healthy subjects who walked under four experimental conditions: (1) without a cane and (2–4) contralateral cane use with 10%, 15%, and 20% body weight support (BWS), respectively. To maintain the same walking speed in all conditions, the cadence was set to 80 steps/min, and the step length was fixed. The hip moment impulses in the frontal plane (i.e., area under the hip ab-adduction moment waveform) and peak hip adduction moments in all conditions were calculated. ResultsContralateral cane use significantly decreased the hip moment impulse in the frontal plane and peak hip adduction moment compared to non-cane use. Moreover, the hip moment impulse in the frontal plane and peak hip adduction moment decreased significantly with increased cane BWS. There were no significant differences in walking speed, cadence, and step length between the four conditions. ConclusionContralateral cane use decreases the hip moment impulse in the frontal plane and peak hip adduction moment in the stance limb. These findings may help clarify how to delay the progression of hip osteoarthritis.