Established Knee Osteoarthritis Research Articles

National Institute of Health and Care Excellence Clinical Criteria for the Diagnosis of Knee Osteoarthritis: A Prospective Diagnostic Accuracy Study in Individuals with Type 2 Diabetes.

The National Institute of Health and Care Excellence (NICE) criteria for osteoarthritis (OA) obviate the need for physical exam or imaging, and their use may improve timely diagnosis of OA. However, they have not been validated. Within a larger study of individuals with type 2 diabetes, participants with and without self-reported knee pain underwent assessment of the NICE criteria for knee OA by questionnaire (index test), and clinical evaluation for established or possible knee OA by a rheumatologist (reference standard). We calculated the sensitivity, specificity, likelihood ratio positive (LR+) and likelihood ratio negative (LR-) of the NICE criteria and modified NICE criteria without the stiffness criterion. Our study included 96 participants: mean age 65.4 (SD 8.3) years and 52% were women. Individuals who fulfilled NICE criteria for knee OA (55.2%) included a spectrum of pain severity on a 11-point pain numeric rating scale with a median score of 5 (range: 1-9). Rheumatologist assessment identified 56 (58.3%) participants with symptomatic knee OA. The sensitivity, specificity, LR+, and LR- of NICE criteria for symptomatic knee OA were 0.84 (95% CI 0.74, 0.94), 0.85 (95% CI 0.74, 0.96), 5.6 and 0.19, respectively. For modified NICE criteria, these were 0.89 (95% CI 0.82, 0.97), 0.85 (95% CI 0.74, 0.96), 5.93 and 0.13. The NICE criteria have high sensitivity and specificity for detecting symptomatic knee OA in a population with type 2 diabetes. We found that a modified version, omitting the stiffness criterion, performed similarly. These criteria should be validated in other settings and populations.

Early-stage vs established knee osteoarthritis: A comparative observational study on prevalence and changes in pain, function and quality of life after supervised exercise and education among 10,365 patients

ObjectiveCompare prevalence and changes in outcomes among established and early-stage knee osteoarthritis (KOA) patients undertaking supervised exercise and education. MethodsPatients from Good Life with osteoArthritis in Denmark (GLA:D®) were stratified into three groups: established KOA (ACR/EULAR criteria), early-stage KOA (diagnostic-model-outcome ≥70%, Criteria for the Early Diagnosis of knee Osteoarthritis) or potential early-stage KOA (diagnostic-model-outcome 30-69%). Mixed-effects models and the proportion of patients by group achieving minimal clinically important improvements (MCIIs) were used to investigate changes in VAS pain intensity (0-100mm), Knee injury and Osteoarthritis Outcome Score (KOOS) Quality of Life (QoL; 0-100), 40m Walk test and 30s chair-stand test at 3 and 12 months. ResultsCompared to established KOA (61% of 10,365 patients), early-stage KOA (27%) had similar knee pain at baseline (mean (SD); 51 (22) vs 45 (22)), and improvement in pain (mean (95% CI) -15 (-15 to -14) vs -14 (-15 to -13), ≥MCII: 55% vs 54%) and KOOS QoL (≥MCII: 50% vs 50%) at 12 months, and in walking speed (≥MCII: 56% vs 52%) and chair-stands (≥MCII: 55% vs 52%) at 3 months. Compared to either group, potential early-stage KOA (10%) had lower baseline pain (34 (32.7)) and less improvement in pain (-9.8 (-11.3 to -8.2; ≥MCII: 47%)), but comparable improvements in KOOS QoL (≥MCII: 50%), walking speed (≥MCII: 51%) and chair-stands (≥MCII: 51%). ConclusionPatients with early-stage KOA achieved comparable improvements at 3 and 12 months to those with established KOA, supporting supervised exercise and education as a viable management strategy for early-stage KOA.

Varus Thrust Assessment Identified Responders to Quadriceps Exercise in Individuals at Risk of or with Knee Osteoarthritis.

Identification of responders/non-responders to unsupervised therapeutic exercise represents a critical challenge towards establishment of tailored self-management at home. Focusing on visualized varus thrust during gait as a possible effect moderator, this study determined whether and how varus thrust influences the therapeutic effects of home-based quadriceps exercise in individuals at increased risk of, or with, established knee osteoarthritis. This study is a secondary subgroup analysis of a randomized controlled trial (n = 50). Varus thrust at baseline was assessed via recorded gait movie. Analysis of covariance and subsequent mediation analysis were used to determine whether and how varus thrust influences the therapeutic effect of home-based quadriceps exercise after adjustment for covariates. To address the possible distinct impact of varus thrust on unsupervised and supervised exercise, the results were cross-checked with previous supervised exercise cohort using a meta-analysis. Individuals without varus thrust displayed greater and clinically meaningful pain-relief after exercise after adjustment for covariates. The greater pain-relief in individuals without varus thrust was attributed, at least partly, to an improvement in knee flexion range of motion. Notably, the meta-analysis revealed that unsupervised and supervised exercise programs induce consistent and clinically meaningful pain reduction in individuals without varus thrust. Varus thrust is a robust effect moderator of the pain reducing effect of quadriceps exercise. Further, greater pain reduction may be a function of improvement of knee flexion range of motion. These studies provide evidence that varus thrust assessment represents valuable approach to identify responders/non-responders to quadriceps exercise even for unsupervised protocol at their home environment.

Statin use and longitudinal changes in quantitative MRI-based biomarkers of thigh muscle quality: data from Osteoarthritis Initiative.

To assess whetherchanges in MRI-based measures of thigh muscle quality associated with statin use in participants with and without/at-risk of knee osteoarthritis. This retrospective cohort study used data from the Osteoarthritis Initiative study. Statin users and non-users were matched for relevant covariates using 1:1 propensity-score matching. Participants were further stratified according to baseline radiographic knee osteoarthritis status. We used a validated deep-learning method for thigh muscle MRI segmentation and calculation of muscle quality biomarkers at baseline, 2nd, and 4th visits. Mean difference and 95% confidence intervals (CI) in longitudinal 4-year measurements of muscle quality biomarkers, including cross-sectional area, intramuscular adipose tissue, contractile percent, and knee extensors and flexors maximum and specific contractile force (force/muscle area) were the outcomes of interest. After matching, 3772 thighs of 1910 participants were included (1886 thighs of statin-users: 1886 of non-users; age: 62 ± 9 years (average ± standard deviation), range: 45-79; female/male: 1). During 4 years, statin use was associated with a slight decrease in muscle quality, indicated by decreased knee extension maximum (mean-difference, 95% CI: - 1.85 N/year, - 3.23 to - 0.47) and specific contractile force (- 0.04 N/cm2/year, - 0.07 to - 0.01),decreased thigh muscle contractile percent (- 0.03%/year, - 0.06 to - 0.01), and increased thigh intramuscular adipose tissue (3.06 mm2/year, 0.53to 5.59). Stratified analyses showed decreased muscle quality only in participants without/at-risk of knee osteoarthritis but not those with established knee osteoarthritis. Statin use is associated with a slight decrease in MRI-based measures of thigh muscle quality over 4 years. However, considering statins' substantial cardiovascular benefits, these slight muscle changes may be relatively less important in overall patient care.

Does Bisphosphonate Increase the Sclerosis of Tibial Subchondral Bone in the Progression of Knee Osteoarthritis-A Propensity Score Matching Cohort Study Based on Osteoarthritis Initiative.

Bisphosphonate has great potential in KOA therapy, but whether the anti-resorption mechanism of bisphosphonate aggravates sclerosis of subchondral bone remains unclear. We found that bisphosphonate use did not increase sclerosis of subchondral bone in established KOA, perhaps resolving some concerns about bisphosphonate in patients with KOA.Introduction: Most studies have focused on the protective effect of bisphosphonate on early knee osteoarthritis (KOA) through its anti-resorption mechanism in osteoclasts. However, late KOA has a decreased rate of resorption, which is the opposite of early KOA. The risk of subchondral bone sclerosis in late KOA after using bisphosphonate has not been investigated using morphometry.Methods: Forty-five patients who had ever used bisphosphonate (or 33 patients with current use) were matched with controls through propensity matching methods, including age, body mass index (BMI), sex, health status (12-Item Short Form Survey physical health score), physical activity level (Physical Activity Scale for the Elderly score), vitamin D use, and calcium use. At the baseline and 12-month (or 18-month) follow-up, bone mineral density (BMD) of the tibia and hip was measured by dual-energy X-ray absorptiometry (DXA), and medial tibial subchondral bone morphometry: bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.Sp) were calculated based on 3-T trabecular MRI. Data were obtained from the Bone Ancillary Study in the Osteoarthritis Initiative (OAI) project.Results: The yearly percentage change in hip BMD of the current bisphosphonate-use group was significantly greater than that of the non-bisphosphonate-use group (0.7% vs. −1%, P = 0.02). The other outcomes (BV/TV, Tb.N, Tb.Sp, Tb.Th, tibia medial BMD, and tibia lateral BMD) between the two groups presented no significant difference. The non-bisphosphonate-use group experienced a significant increase in Tb.Th [2%, 95% CI = (1%, 4%), P = 0.01], while the bisphosphonate-use group presented no significant change [1%, 95% CI = (−2%, 4%), P = 0.54].Conclusions: Bisphosphonate use did not increase sclerosis of subchondral bone in established KOA. Bisphosphonate might have a stage-dependent effect on subchondral bone in KOA initiation and progression.

Flexion contracture is a risk factor for knee osteoarthritis incidence, progression and earlier arthroplasty: Data from the Osteoarthritis Initiative.

Knee joint osteoarthritis (OA) is often accompanied by flexion contracture (FC), but the impact of FC on important outcomes across the spectrum of OA, such as the incidence, progression and need for total knee arthroplasty (TKA), is not well established. We evaluated whether the presence and/or severity of knee FC were risk factors for worse OA clinical outcomes, radiographic incidence and progression as well as time to TKA. We evaluated longitudinal 9-year data from the Osteoarthritis Initiative (OAI) database for 3 sub-cohorts: at-risk of knee OA (n=3284), radiographically established knee OA (n=1390), and low-risk controls (n=122). We classified knee FC as none, mild, moderate or severe based on knee extension at enrolment. Knee OA outcomes were extracted from the database. FC was present in 32.4% of knees. Participants with FC had increased knee OA incidence with joint space narrowing in the definition (corrected odds ratio 1.31 [95% confidence interval (CI) 1.04-1.64]). The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores for pain, stiffness and function were worse with than without FC at nearly all times (p<0.001). Effect estimates were significant for all 3 WOMAC sub-scales comparing FC to no FC (pain: 0.15 [95% CI 0.02-0.28], stiffness: 0.11 [0.05-0.18], function: 0.49 [0.05-0.93]). Individuals with knee FC had higher Kellgren and Lawrence grade (effect size 0.31 [95% CI 0.25-0.37]) and were more likely to undergo TKA (corrected odds ratio 1.37 [95% CI 1.10-1.71]) than those without FC. All outcomes were worse with increasing FC severity. The presence of knee FC at enrolment was a risk factor for radiographic OA incidence including joint space narrowing, worse clinical outcomes, radiographic progression and the need for early TKA. Treatment of knee FC may represent an option across the OA spectrum. Further research is needed to evaluate the pathophysiology, joint structure alterations and longitudinal impact of treating FC in individuals with knee OA.

Pathological features of established osteoarthritis with hydrathrosis are similar to rheumatoid arthritis

The prevalence of rheumatoid arthritis (RA) and knee osteoarthritis (OA) is increasing with our aging society. Some reports suggest that OA with effusion synovitis develops into RA and early OA patients with effusion are pathologically similar to those with RA. The purpose of this study was to examine the relationship between histological features of established knee OA with or without effusion and RA. Seventy-nine patients in which synovial specimens were obtained during total knee arthroplasty were included. Patients were divided into an RA group, OA with effusion (OA+) group, and OA without effusion (OA-) group. The Rooney synovitis score and serum matrix metalloproteinase (MMP)-3 levels were compared among groups. We also examined the correlation between the Rooney synovitis score and its sub-scores with MMP-3 levels. The total Rooney score was significantly higher in the RA group than in the OA+ and OA- groups (25.4 vs 17.1, p < 0.01; 25.4 vs 13.5, p < 0.001, respectively). This score also was significantly higher in the OA+ group than in the OA- group (p < 0.05). The proliferating blood vessels score, perivascular infiltrates of lymphocytes score, focal aggregates of lymphocytes score, and diffuse infiltrates of lymphocytes score were significantly higher in the RA group than in the OA- group (7.05 vs 3.29, 4.95 vs 3.43, 3.29 vs 1.46, and 2.26 vs 1.18, respectively; p < 0.05), but not compared with the OA+ group. The total Rooney score demonstrated a significantly positive correlation with serum MMP-3 levels in the RA group (r = 0.61; 95% CI: 0.28 to 0.81; p < 0.01) and in the OA+ group (r = 0.57; 95% CI: 0.24 to 0.78; p < 0.01). Previous reports showed the histological similarity between RA and early OA with effusion. We confirmed this histological similarity, in particular the distribution of lymphocytes, between RA and established OA with effusion. It is possible that cases diagnosed as OA with effusion might progress to overt RA. • Histological similarity was observed between RA and established OA with effusion.

1462-P: Baseline Gait Speed Can Predict Diabetes Incidence in Individuals with or at Risk of Knee Osteoarthritis: A Longitudinal Study Using Data from the Osteoarthritis Initiative

Introduction: The coexistence of Knee osteoarthritis (OA) and diabetes mellitus (DM) can be explained by shared risk factors such as age and obesity. Both conditions adversely affect gait speed, however, longitudinal studies investigating the relationship between gait speed and DM incidence in people with or at elevated risk for knee OA are lacking. Therefore, the aim was to investigate the association between baseline gait speed and risk of DM incidence among people with or at risk for knee OA. Methods: Participants from the osteoarthritis initiative, aged 45 to 79 years, who were at risk or had knee OA and followed up from baseline to 96-month visit were included. Self-reported diabetes was used over a 4-time points to identify DM incidence. Gait speed was measured at baseline using 20 meter walk test. Body mass index (BMI) was measured and included as a time-dependent covariate. Generalized estimating equations with logistic regression were utilized to examine the association between baseline gait speed and DM incidence. Results: Increased baseline gait speed was significantly associated with decreased odds of incident DM after adjustments for covariates (OR 0.52). The risk of DM incidence decreased 48% for each 0.1 m/s increase in gait speed at baseline for individuals with established or at risk of knee OA. Sensitivity analysis showed that the significant results were maintained with those at risk of OA (OR 0.45) but not in those with established knee OA. Conclusion: Increasing baseline gait speed in general was significantly associated with a lower risk of DM incidence over time. However, the association disappeared after adjustments for BMI in people with established knee OA, suggesting that the majority of this association might be explained by higher weight. Therefore, future research should examine closely the link between gait speed and well-defined DM risk using objective measures such as glucose level. Disclosure A.M. Alenazi: None. B. Alqahtani: None. M.M. Alshehri: None. A.D. Alanazi: None. K. Khunti: Advisory Panel; Self; Amgen, AstraZeneca, Bayer AG, Berlin-Chemie AG, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Menarini Group, Merck Sharp &amp; Dohme Corp., Napp Pharmaceuticals, Novartis AG, Novo Nordisk A/S, Roche Pharma, Sanofi-Aventis, Servier. Board Member; Self; AstraZeneca, Eli Lilly and Company, Merck Sharp &amp; Dohme Corp., Novo Nordisk A/S, Sanofi-Aventis. Consultant; Self; Amgen, AstraZeneca, Bayer AG, Berlin-Chemie AG, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Menarini Group, Merck Sharp &amp; Dohme Corp., Napp Pharmaceuticals, Novartis AG, Novo Nordisk A/S, Roche Pharma, Sanofi-Aventis, Servier. Research Support; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Merck Sharp &amp; Dohme Corp., Novartis AG, Novo Nordisk A/S, Pfizer Inc., Sanofi-Aventis, Servier. Speaker’s Bureau; Self; Amgen, AstraZeneca, Bayer AG, Berlin-Chemie AG, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Menarini Group, Merck Sharp &amp; Dohme Corp., Napp Pharmaceuticals, Novartis AG, Novo Nordisk A/S, Roche Pharma, Sanofi-Aventis, Servier. V. Vennu: None. N.A. Segal: None. S.M. Bindawas: None.

Bone marrow lesions in knee osteoarthritis: regional differences in tibial subchondral bone microstructure and their association with cartilage degeneration

The aim of this study was to investigate how bone microstructure within bone marrow lesions (BMLs) relates to the bone and cartilage across the whole human tibial plateau. Thirty-two tibial plateaus from patients with osteoarthritis (OA) at total knee arthroplasty and eleven age-matched non-OA controls, were scanned exvivo by MRI to identify BMLs and by micro CT to quantitate the subchondral (plate and trabecular) bone microstructure. For cartilage evaluation, specimens were processed histologically. BMLs were detected in 75% of the OA samples (OA-BML), located predominantly in the anterior-medial (AM) region. In contrast to non-OA control and OA-no BML, in OA-BML differences in microstructure were significantly more evident between subregions. In OA-BML, the AM region contained the most prominent structural alterations. Between-group comparisons showed that the AM region of the OA-BML group had significantly higher histological degeneration (OARSI grade) (P<.0001, P<.05), thicker subchondral plate (P<.05, P<.05), trabeculae that are more anisotropic (P<.0001, P<.05), well connected (P<.05, P=n.s), and more plate-like (P<0.05, P<0.05), compared to controls and OA-no BML at this site. Compared to controls, OA-no BML had significantly higher OARSI grade (P<.0001), and lower trabecular number (P<.05). In established knee OA, both the extent of cartilage damage and microstructural degeneration of the subchondral bone were dependent on the presence of a BML. In OA-no BML, bone microstructural alterations are consistent with a bone attrition phase of the disease. Thus, the use of BMLs as MRI image-based biomarkers appear to inform on the degenerative state within the osteochondral unit.

Physical inactivity and knee osteoarthritis in guinea pigs

To investigate whether and how a sedentary lifestyle contributes to knee osteoarthritis (OA) incidence and severity. An experiment was conducted using Hartley guinea pigs, an established idiopathic knee OA model. To simulate a sedentary lifestyle, growing animals (n=18) were housed for 22 weeks in small cages that restricted their mobility, while another group of animals (n=17) received daily treadmill exercise to simulate moderate physical activity. After the experiment, histological assessments, biochemical assays, and mechanical testing were conducted to compare tibial articular cartilage structure, strength, and degree of OA degeneration between sedentary and physically active animals. Groups were also compared based on body weight and composition, as well as gut microbial community composition assessed using fecal 16S rRNA gene sequencing. Prevalence of knee OA was similar between sedentary and physically active animals, but severity of the disease (cartilage lesion depth) was substantially greater in the sedentary group (P=0.02). In addition, during the experiment, sedentary animals developed cartilage with lower aggrecan quantity (P=0.03) and accumulated more body weight (P=0.005) and visceral adiposity (P=0.007). Groups did not differ greatly, however, in terms of cartilage thickness, collagen quantity, or stiffness, nor in terms of muscle weight, subcutaneous adiposity, or gut microbial community composition. Our findings indicate that a sedentary lifestyle promotes the development of knee OA, particularly by enhancing disease severity rather than risk of onset, and this potentially occurs through multiple pathways including by engendering growth of functionally deficient joint tissues and the accumulation of excess body weight and adiposity.

The effects of cryotherapy on pain and function in individuals with knee osteoarthritis: a systematic review of randomized controlled trials

Objective: To investigate the effectiveness of cryotherapy on pain and physical function in knee osteoarthritis. Data sources: An electronic search was performed up to February 2019 on PubMed/MEDLINE, EMBASE, CINAHL, Lilacs, Cochrane, Web of Science, Ibecs, and Scielo databases with keywords knee osteoarthritis and cryotherapy. Methods: Two authors independently performed the study selection. All languages and publication dates were considered. The PEDro scale was used to assess the methodological quality of the studies, and the body of evidence was analyzed and synthesized using the Grading of Recommendations, Assessment, Development, and Evaluation approach. The clinical relevance of the included studies was evaluated using the criteria proposed in the Cochrane Handbook for Systematic Reviews of Interventions. Results: Of the five studies, 202 subjects were included. All studies included participants with established knee osteoarthritis. The mean PEDro score was 4.20/10, and meta-analysis was not possible due to heterogeneity among the studies. The mean clinical relevance was 3/5. Only two studies were considered for analysis based on the GRADE approach, and low level of evidence was synthesized regarding the effectiveness of cryotherapy for pain management, knee stiffness, knee range of motion, and physical function. Application techniques, frequency, and duration did not affect outcomes. Conclusions: There were insufficient primary studies to draw any conclusions about the effectiveness of cryotherapy on pain and physical function on individuals with knee osteoarthritis.

Osteoarthritis of the knee in the elderly: is knee replacement always justified?

Osteoarthritis is a condition that mostly affects the elderly population and tends to be localized to the knee joint. At old age, active treatment options are limited by co-morbidities and a higher risk for surgical complications. Therefore, the search for strategies that could become a temporary alternative to knee replacement is a pressing concern. The aim of this study was to analyze how justifiable is total knee replacement in elderly patients with knee osteoarthritis and to propose a less aggressive therapeutic alternative to this surgery. The study included 178 patients over 60 years of age with clinically established knee osteoarthritis who had been previously recommended knee replacement but chosen not to undergo it. The choice of a treatment strategy tested in the study was based on the original grading scale for the evaluation of the knee joint dislocation syndrome. The treatment consisted of therapeutic arthroscopy and intraarticular injections of hyaluronic acid and platelet-rich plasma (PRP). The data were processed in Statistica 12. Data analysis revealed that 39.3% of the participants did not have compelling indications for knee replacement. The proposed combination therapy with intraarticular PRP injections and arthroscopy allowed all the patients to delay knee replacement for at least a year; unaided by arthroscopy, intraarticular injections worked well for only 40%.

The association between smoking and knee osteoarthritis in a cohort of Danish patients undergoing knee arthroscopy

BackgroundIt has been suggested that smoking is associated with reduced risk of knee osteoarthritis (OA). However, supplementary studies are needed to further investigate any such potential association. Thus, our aim was to examine the relationship between smoking and early or more established knee OA in a cohort of relatively young patients with meniscal tears.MethodsThis cross-sectional study included 620 participants from the Knee Arthroscopy Cohort Southern Denmark (KACS) undergoing knee arthroscopy for a meniscal tear (mean age 49.2 (18.0–76.8) years). Recruitment of patients was performed between February 1, 2013, and January 31, 2015, at four different hospitals in Denmark. We defined early or more established knee OA as the combination of patient-reported frequent knee pain, degenerative meniscal tissue and presence of cartilage defects assessed by the operating surgeons. The relationship between smoking status and knee OA was examined by risk ratio (RR) with a 95% confidence interval (CI), estimated from logistic regression adjusted for age, sex, BMI, education, work status and level of physical activity.ResultsThe prevalence of early or more established knee OA was 37.7% in current smokers and 45.0% in non-smokers. We found no statistically significant association between current smoking and knee OA (adjusted RR 1.09, 95% CI 0.91–1.30).ConclusionsThis study found no relationship between current smoking and early or more established knee OA in a cohort of patients undergoing arthroscopic meniscal surgery. Thus, the inverse association between smoking and knee OA that has been suggested by previous studies was not confirmed.

Marked and rapid change of bone shape in acutely ACL injured knees – an exploratory analysis of the Kanon trial

To investigate changes in knee 3D bone shape over the first 5 years after acute anterior cruciate ligament (ACL) injury in participants of the randomized controlled KANON-trial. Serial MR images over 5 years from 121 young (32 women, mean age 26.1 years) adults with an acute ACL tear in a previously un-injured knee were analyzed using statistical shape models for bone. A matched reference cohort of 176 individuals was selected from the Osteoarthritis Initiative (OAI). Primary endpoint was change in bone area of the medial femoral condyle; exploratory analyses compared results by treatment and examined other knee regions. Comparisons were made using repeated measures mixed model ANOVA with adjustment for age, sex and body mass index (BMI). Mean medial femur bone area increased 3.2% (78.0 [95% CI 70.2 to 86.4] mm2) over 5 years after ACL injury and most prominently in knees treated with ACL reconstruction (ACLR). A higher rate of increase occurred over the first 2years compared to the latter 3-years (66.2 [59.3 to 73.2] vs 17.6 [12.2 to 23.0] mm2) and was 6.7 times faster than in the reference cohort. The pattern and location of shape change in the extrapolated KANON data was very similar to that observed in another knee-osteoarthritis cohort. 3D shape modelling after acute ACL injury revealed rapid bone shape changes, already evident at 3 months. The bone-change pattern after ACL injury demonstrated flattening and bone growth on the outer margins of the condyles similar to that reported in established knee osteoarthritis.

Effects of glucosamine in patients with osteoarthritis of the knee: a systematic review and meta-analysis

Osteoarthritis (OA) of the knee is one of the main causes of mobility decline in the elderly. Non-surgical treatments such as administration of supplements to strengthen the joint cartilage matrix have become popular not only for pain relief but also for joint preservation. Glucosamine has been used in many countries based on the increasing evidence of its effectiveness for OA. Although there are many previous studies and systematic reviews, the findings vary and different conclusions have been drawn. We aimed to review recent randomized controlled trials on glucosamine for knee OA to reveal up-to-date findings about this supplement. We also performed a meta-analysis of some of the outcomes to overcome the unsolved bias in each study. Eighteen articles written between 2003 and 2016 were analyzed. Many used visual analogue scale (VAS) pain scores and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), which were assessed in our meta-analysis. We found a marginally favorable effect of glucosamine on VAS pain scores. The effect on knee function, as measured by the WOMAC, was small and not significant. A newly established knee OA scale, the Japanese Knee Osteoarthritis Measure (JKOM), is commonly used in Japan. Although the number of subjects was small, the JKOM meta-analysis indicated that glucosamine is superior to a placebo in alleviating knee OA symptoms. Given this, we concluded that glucosamine has the potential to alleviate knee OA pain. Further studies are needed to evaluate the effect of glucosamine on knee function and joint preservation, as well as to evaluate the combined effect with other components, such as chondroitin.

A comparison of characteristics of subjects with early knee osteoarthritis based on two different classification criteria

Purpose: Osteoarthritis (OA) of the knee is one of the leading causes of pain and disability worldwide. The need to identify subjects at the early stages of the disease process, before any significant structural damage, is of clinical relevance. They could be treated with more targeted management strategies to improve their prognosis, and possibly delay or avoid knee replacement surgery. We have previously reported that an early knee OA population is distinct from a normal control group and established knee OA with regard to a number of parameters. Recently, a new early knee OA classification was proposed to bring this closer to primary care by challenging the necessity of MRI. Our objective was to compare the clinical, functional and structural characteristics of subjects with early knee OA, classified based on these 2 different sets of criteria. Methods: Sixty-nine postmenopausal women with either early or established medial knee OA, as well as 31 asymptomatic controls (all women) were included. The established OA (n = 29) group was classified as defined by the American College of Rheumatology classification criteria: knee pain, age above 50, stiffness less than 30 minutes and crepitus. For the early OA group 2 recent classifications were used: 1) Luyten et al. 2012 early knee OA classification (early OA 2012) and 2) Luyten et al. 2017 early knee OA classification (early OA 2017). The inclusion criteria for the early OA 2012 (n = 40) group were: presence of knee pain, a Kellgren & Lawrence (K&L) grade 0, 1 or 2- (osteophytes only, no joint space narrowing) on radiography and presence of two of four MRI criteria: (1) ≥BLOKS grade 2 for size cartilage loss, (2) ≥BLOKS grade 2 for percentage full-thickness cartilage loss, (3) signs of meniscal degeneration and (4) ≥BLOKS grade 2 for size of bone marrow lesions (BMLs) in any one compartment. Subjects were classified as early OA 2017 (n = 25) if: showed K&L grade 0 or 1, and 2 out of the 4 KOOS subscales scored “positive” (≤85%), and at least 1 clinical sign was present: Joint line tenderness, crepitus. Clinical, functional and structural characteristics of all subjects were assessed and compared between the 4 groups. Results: For the clinical assessment, the 2017 early knee OA group showed significantly lower (isometric and isokinetic) quadriceps and hamstrings strength compared to the controls. The 2012 early OA group, on the other hand, showed only significantly lower isometric hamstrings strength compared to the controls. No significant differences were found between the 4 groups regarding performance-based function as measured with Timed up and Go and Stair Climbing Tests. Looking into the psychosocial profile, pain catastrophizing scale subscores, as well as the total score, were significantly higher in the 2012 early OA group compared to the controls, while this was not the case when comparing the 2017 early OA group with the controls. MRI findings indicate that the 2017 early OA group showed no significant differences compared to the controls regarding the size/number of BMLs, in contrast to the 2012 early OA group. The 2017 early OA group showed more and larger cumulative (not specifically medial compartment) cartilage lesions compared to the controls. Conclusions: Current results identify clinical and functional differences when early knee OA is classified with or without MRI findings. The new early knee OA classification (Luyten et al. 2017), intended for use in primary care, captures patients with more knee pain and symptoms, worse self-reported function, as well as weaker knee musculature compared to the previously introduced early knee OA classification (Luyten et al. 2012). The latter one is partially based on MRI findings and thus potentially more appropriate for second line care. Most importantly, further validation and iterations of these criteria is required to more precisely identify patients at higher risk of knee OA development.

Changes in gait characteristics of women with early and established medial knee osteoarthritis: Results from a 2-years longitudinal study

BackgroundDespite the large number of cross-sectional studies on gait in subjects with knee osteoarthritis, there are scarcely any longitudinal studies on gait changes in knee osteoarthritis. MethodsGait analysis was performed on 25 women with early and 18 with established medial knee osteoarthritis, as well as a group of 23 healthy controls. Subjects were asked to walk at their comfortable speed. Kinematic and kinetic data were measured at baseline and after 2years follow-up. FindingsResults indicated that the early osteoarthritis group, similar to established osteoarthritis group, showed significantly higher maximum knee adduction angles compared to the controls during the early stance phase of gait. None of the kinematic or kinetic measures, changed over two years in the early osteoarthritis group. In the established osteoarthritis group, at the time of entry, an increased first and second peak knee adduction moment, as well as higher mid-stance knee adduction moment and knee adduction moment impulse, were present compared to the control and the early osteoarthritis groups. Mid-stance knee adduction moment and knee adduction moment impulse, further increased over two years only in the established osteoarthritis group. For all three groups, the peak knee flexion angle during the stance phase decreased significantly over time. InterpretationIncreased maximum knee adduction angle during stance phase was the only alteration in the gait pattern of subjects with early knee osteoarthritis compared to the controls. This suggests that, unlike in the later stages of the disease, gait is rather stable over two years in early osteoarthritis.

Transforming Growth Factor Beta1 being considered a novel biomarker in knee osteoarthritis

BackgroundAssociations between Transforming Growth Factor beta-1 (TGF-β1), Platelet-derived growth factor BB (PDGF-BB) and C-terminal telopeptide of type I collagen (CTX-1) with pathogenesis of osteoarthritis (OA) have already been established. Therefore, TGF-β1, PDGF-BB and CTX-1 could be used as the potential biomarkers for the diagnosis of this disease. Methods160 knee OA cases and 80 healthy controls were chosen. Serum concentrations of TGF-β1, PDGF–BB and CTX-1 were tested twice on the same samples using Enzyme-Linked Immunosorbent Assay. Knee OA cases were classified using Kellgren-Lawrence (K-L) criteria into four groups. Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index scores were evaluated for all cases. ResultsTGF-β1 serum levels in knee OA cases were significantly higher compared to controls (t=11.37, p<0.01). Average serum level of TGF-β1 was positively associated with K-L grades. The diagnostic efficiency of serum TGF-β1 was proved to be moderate and the cut-point value was 12.11ng/ml showing favorable diagnostic indexes. In contrast, similarities were found not only in serum levels of PDGF-BB and CTX-1 between OA groups and controls but also in WOMAC scores. ConclusionOur findings supported that TGF-β1 has a positive correlation with the severity of knee OA confirmed by radiographs. Therefore, TGF-β1 might serve as a potential biomarker in established knee OA.

Dynamic and static knee alignment at baseline predict structural abnormalities on MRI associated with medial compartment knee osteoarthritis after 2 years

BackgroundDynamic and static varus alignment, both, have been reported as risk factors associated with structural progression of knee osteoarthritis. However the association of none of the static and dynamic alignment with structural, clinical, and functional progression associated with knee osteoarthritis has not been assessed yet in a longitudinal study. MethodsForty-seven women with early and established medial knee osteoarthritis were evaluated. Static and dynamic alignment as well as MRI detected structural features, clinical, and functional characteristics of patients were assessed at baseline and at 2 years follow-up. Associations between baseline static and dynamic alignment with structural, functional, and clinical characteristics at the time of entry, as well as the changes over 2 years were evaluated. FindingsBoth static and dynamic varus alignment at baseline were significantly associated with osteoarthritis related tibio-femoral joint structural abnormalities detected on MRI, at the time of entry. Only the magnitude of varus thrust at baseline was predictive of the changes in the presence of meniscal maceration over two years. None of the static or dynamic measures of knee joint alignment were associated with clinical characteristics associated with medial knee osteoarthritis. InterpretationThe key finding of this study is that both frontal plane dynamic and static alignment, are associated with structural abnormalities in patients with medial knee osteoarthritis.

Signs of knee osteoarthritis common in 620 patients undergoing arthroscopic surgery for meniscal tear

Background and purpose — Recent evidence has questioned the effect of arthroscopic knee surgery for middle-aged and older patients with degenerative meniscal tears with or without concomitant radiographic knee osteoarthritis (OA). We investigated the prevalence of early or more established knee OA and patients’ characteristics in a cohort of patients undergoing arthroscopic surgery for a meniscal tear.Patients and methods — 641 patients assigned for arthroscopy on suspicion of meniscus tear were consecutively recruited from February 2013 through January 2015. Of these, 620 patients (mean age 49 (18–77) years, 57% men) with full datasets available were included in the present study. Prior to surgery, patients completed questionnaires regarding onset of symptoms, duration of symptoms, and mechanical symptoms along with the knee injury and osteoarthritis outcome score (KOOS). At arthroscopy, the operating surgeon recorded information about meniscal pathology and cartilage damage. Early or more established knee OA was defined as the combination of self-reported frequent knee pain, cartilage damage, and the presence of degenerative meniscal tissue.Results — 43% of patients (269 of 620) had early or more established knee OA. Of these, a large proportion had severe cartilage lesions with almost half having a severe cartilage lesion in at least 1 knee compartment.Interpretation — Based on a definition including frequent knee pain, cartilage damage, and degenerative meniscal tissue, early or more established knee OA was present in 43% of patients undergoing knee arthroscopy for meniscal tear.