Association between weight gain and knee osteoarthritis: a systematic review.

OBJECTIVE: Although weight loss is recommended to manage knee osteoarthritis (KOA), adults tend to gain weight with age which may affect KOA symptoms and progression. We conducted a systematic review and data synthesis to investigate the association between weight gain and KOA, defined by clinical features, structural progression, and total knee replacement (TKR). DESIGN: MEDLINE and EMBASE were systematically searched for controlled trials and cohort studies of participants with (or at risk of) KOA examining the relationship between weight gain and KOA clinical features (pain, function, quality of life), structural progression, and TKR. Risk of bias was assessed using the ROBINS-I tool. Results were organised by outcome, with meta-analyses performed where appropriate. RESULTS: Twenty-three studies were included. Results showed significant detrimental effects of weight gain on pain (4 of 7 studies), stiffness (2 of 2 studies), function (5 of 6 studies), and the single studies examining quality of life, and clinical and radiographic KOA. Weight gain adversely affected cartilage (6 of 9 studies), bone marrow lesions (1 of 4 studies), meniscal damage (1 of 3 studies) and effusion/synovitis (1 of 1 study). Weight gain significantly increased TKR (3 of 6 studies): meta-analysis of 2 with available data demonstrated significant increases in TKR/5 kg weight gain in women, HR 1.34 (95% CI 1.18-1.51), and in men, HR 1.25 (95% CI 1.16-1.34). CONCLUSIONS: Weight gain in adults is associated with increased clinical and structural KOA and TKR. Prevention of weight gain should be considered to improve outcomes in KOA.

Metformin as a potential disease-modifying drug in osteoarthritis: a systematic review of pre-clinical and human studies.

OBJECTIVE: Osteoarthritis causes significant pain and disability with no approved disease-modifying drugs. We systematically reviewed the evidence from both pre-clinical and human studies for the potential disease-modifying effect of metformin in osteoarthritis. METHODS: Ovid Medline, Embase and CINAHL were searched between inception and June 2021 using MeSH terms and key words to identify studies examining the association between metformin use and outcome measures related to osteoarthritis. Two reviewers performed the risk of bias assessment and 3 reviewers extracted data independently. Qualitative evidence synthesis was performed. This systematic review is registered on PROSPERO (CRD42021261052 and CRD42021261060). RESULTS: Fifteen (10 pre-clinical and 5 human) studies were included. Most studies (10 pre-clinical and 3 human) assessed the effect of metformin using knee osteoarthritis models. In pre-clinical studies, metformin was assessed for the effect on structural outcomes (n = 10); immunomodulation (n = 5); pain (n = 4); and molecular pathways of its effect in osteoarthritis (n = 7). For human studies, metformin was evaluated for the effect on structural progression (n = 3); pain (n = 1); and immunomodulation (n = 1). Overall, pre-clinical studies consistently showed metformin having a chondroprotective, immunomodulatory and analgesic effect in osteoarthritis, predominantly mediated by adenosine monophosphate-activated protein kinase activation. Evidence from human studies, although limited, was consistent with findings in pre-clinical studies. CONCLUSION: We found consistent evidence across pre-clinical and human studies to support a favourable effect of metformin on chondroprotection, immunomodulation and pain reduction in knee osteoarthritis. Further high-quality clinical trials are needed to confirm these findings as metformin could be a novel therapeutic drug for the treatment of osteoarthritis.

Does preoperative neuropathic-like pain and central sensitisation affect the post-operative outcome of knee joint replacement for osteoarthritis? A systematic review and meta analysis.

BACKGROUND: Almost a third of those undergoing knee replacement for osteoarthritis have poor outcomes despite technically successful surgery. Preoperative neuropathic-like pain and/or pain sensitisation may increase the risk of pain following joint replacement. OBJECTIVE: To examine whether preoperative neuropathic-like pain and pain sensitisation predicts pain, function and satisfaction following joint replacement for knee osteoarthritis. DESIGN: Systematic review with meta-analysis. METHODS: Medline, EMBASE and CINAHL were systematically searched until March 2020. Studies detecting neuropathic-like pain and/or sensitisation using self-report questionnaires prior to knee replacement for osteoarthritis, and relating this to post-operative outcomes were identified. Data extraction, risk of bias assessment and meta-analysis were performed, where appropriate. RESULTS: Five manuscripts, including one preprint, examining six cohorts were included: four used painDETECT or modified painDETECT, one the Self-Report Leeds Assessment of Neuropathic Symptoms and Signs, and another the Central Sensitisation Inventory to identify preoperative characteristics. Three studies showed preoperative neuropathic-like pain or sensitisation was associated with more intense post-operative pain. All four studies examining the risk of significant pain after knee replacement suggested it was increased after >3 months. The only study examining patient satisfaction and function found reduced satisfaction, but no difference in function in those with preoperative sensitisation. Meta-analysis found the relative risk of increased pain following knee replacement in those with neuropathic-like pain (painDETECT ≥13) to be 2.05 (95% confidence intervals 1.51, 2.79). CONCLUSION: These results provide consistent but limited evidence that self-report tools detecting neuropathic-like pain and/or pain sensitisation, predict patients at higher risk of pain following knee replacement.

KARAOKE: Krill oil versus placebo in the treatment of knee osteoarthritis: protocol for a randomised controlled trial.

BACKGROUND: Knee osteoarthritis (OA) is a common and important cause of pain and disability, but interventions aimed at modifying structures visible on imaging have been disappointing. While OA affects the whole joint, synovitis and effusion have been recognised as having a role in the pathogenesis of OA. Krill oil reduces knee pain and systemic inflammation and could be used for targeting inflammatory mechanisms of OA. METHODS/DESIGN: We will recruit 260 patients with clinical knee OA, significant knee pain and effusion-synovitis present on MRI in five Australian cities (Hobart, Melbourne, Sydney, Adelaide and Perth). These patients will be randomly allocated to the two arms of the study, receiving 2 g/day krill oil or inert placebo daily for 6 months. MRI of the study knee will be performed at screening and after 6 months. Knee symptoms, function and MRI structural abnormalities will be assessed using validated methods. Safety data will be recorded. Primary outcomes are absolute change in knee pain (assessed by visual analog score) and change in size of knee effusion-synovitis over 24 weeks. Secondary outcomes include improvement in knee pain over 4, 8, 12, 16 and 20 weeks. The primary analyses will be intention-to-treat analyses of primary and secondary outcomes. Per protocol analyses adjusting for missing data and for treatment compliance will be performed as the secondary analyses. DISCUSSION: This study will provide high-quality evidence to assess whether krill oil 2 g/day reduces pain and effusion-synovitis size in older adults with clinical knee OA and knee effusion-synovitis. If krill oil is effective and confirmed to be safe, we will provide compelling evidence that krill oil improves pain and function, changes disease trajectory and slows disease progression in OA. Given the lack of approved therapies for slowing disease progression in OA, and moderate cost of krill oil, these findings will be readily translated into clinical practice. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12616000726459. Registered on 02 June 2016. Universal Trial Number (UTN) U1111-1181-7087.

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

OBJECTIVE: 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. DESIGN: Thirty-two tibial plateaus from patients with osteoarthritis (OA) at total knee arthroplasty and eleven age-matched non-OA controls, were scanned ex vivo 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. RESULTS: 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). CONCLUSION: 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.

Factors associated with prevalent and incident foot pain: data from the Tasmanian Older Adult Cohort Study.

OBJECTIVES: To describe factors associated with prevalent and incident foot pain in a population-based cohort of older adults (n = 1092). STUDY DESIGN: Longitudinal observational study. MAIN OUTCOME MEASURES: Prevalent foot pain, incident foot pain after 5 years. METHODS: Potential correlates included demographic factors, anthropometry, leg strength, metabolic factors, steps per day (using pedometer), pain at 6 other sites, and psychological wellbeing. Data were analysed using log binomial models. RESULTS: Participants were aged 50-80 years (mean 63 years), 49% male, mean body mass index (BMI) 27.8 ± 4.7 at baseline. The prevalence of foot pain at baseline was 38% and the incidence of new pain over 5 years was 20%. BMI, pain at other sites (neck, hands, knees, pain at three or more sites), and poorer psychological wellbeing were independently associated with baseline foot pain. Baseline BMI and pain in the neck, hands, and knees were independently associated with incident foot pain; but change in weight or BMI, total number of painful joints and psychological wellbeing were not. Self-reported diabetes and cigarette smoking were not associated with prevalent or incident foot pain. CONCLUSIONS: This study demonstrates that greater body weight and joint pain at multiple sites were consistently associated with prevalent foot pain and predict incident foot pain. Addressing excess body mass and taking a global approach to the treatment of pain may reduce the prevalence and incidence of foot pain in older adults.

Systematic scoping review of patients' perceived needs of health services for osteoporosis.

Health service planners, administrators and providers need to understand the patients' perspective of health services related to osteoporosis to optimise health outcomes. The aims of this study were to systematically identify and review the literature regarding patients' perceived health service needs relating to osteoporosis and osteopenia. A systematic scoping review was performed of publications in MEDLINE, EMBASE, CINAHL and PsycINFO (1990-2016). Descriptive data regarding study design and methodology were extracted and risk of bias assessed. Aggregates of patients' perceived needs of osteoporosis health services were categorised. Thirty-three studies (19 quantitative and 14 qualitative) from 1027 were relevant. The following areas of perceived need emerged: (1) patients sought healthcare from doctors to obtain information and initiate management. They were dissatisfied with poor communication, lack of time and poor continuity of care. (2) Patients perceived a role for osteoporosis pharmacotherapy but were concerned about medication administration and adverse effects. (3) Patients believed that exercise and vitamin supplementation were important, but there is a lack of data examining the needs for other non-pharmacological measures such as smoking cessation and alcohol. (4) Patients wanted diagnostic evaluation and ongoing surveillance of their bone health. This review identified patients' needs for better communication with their healthcare providers. It also showed that a number of important cornerstones of therapy for osteoporosis, such as pharmacotherapy and exercise, are identified as important by patients, as well as ongoing surveillance of bone health. Understanding patients' perceived needs and aligning them with responsive and evidence-informed service models are likely to optimise patient outcomes.

Meniscal extrusion and bone marrow lesions are associated with incident and progressive knee osteoarthritis.

OBJECTIVE: Whether meniscal extrusion and bone marrow lesions (BMLs) are independently associated with the risk of knee osteoarthritis (OA) is unknown. METHODS: Data was extracted from the Osteoarthritis Initiative (OAI) cohort. Participants were grouped according to the absence (Kellgren-Lawrence (KL) grade ≤ 1, n = 2120) or presence (KL ≥ 2, n = 2249) of radiographic OA (ROA). Baseline meniscal extrusion and tibial BMLs were assessed. Tibial plateau cartilage volume was assessed at baseline and 72 months, while radiographic disease was assessed at baseline and 48 months. Total knee replacement (TKR) was assessed at 72 months. RESULTS: In those with ROA, the presence of a baseline meniscal extrusion (independent of BMLs) was associated with accelerated cartilage volume loss (medial tibia: -2.1%/annum vs -1.5%; lateral: -2.6%/annum vs -1.6%; both P < 0.001), progressive ROA and TKR (Odds ratio (OR) range 1.4-1.8; 95% CI range 1.1-2.9). The presence of a baseline BML was associated with accelerated cartilage volume loss (medial tibia: -2.1%/annum vs -1.6%; lateral: -1.9%/annum vs -1.6%; P ≤ 0.02), progressive ROA and joint replacement (OR range 1.5-2.4; 95% CI range 1.1-3.4). In those with no ROA, a baseline medial meniscal extrusion was associated with accelerated cartilage volume loss (medial tibia: -2.1%/annum vs -1.2%, P < 0.001), and a baseline medial BML with incident ROA (OR 1.7, 95% CI 1.1 to 2.9). CONCLUSIONS: The presence of baseline meniscal extrusion and BMLs are associated with incident and progressive knee of each other (OA) and represent important structural targets for the treatment and prevention of knee OA.

Management options for femoroacetabular impingement: a systematic review of symptom and structural outcomes.

OBJECTIVE: The optimal therapy for femoroacetabular impingement (FAI) is unclear. The aim of this systematic review was to examine the evidence for surgical and non-surgical treatment of FAI on symptom and structural outcomes. DESIGN: MEDLINE and EMBASE were searched electronically. Surgical and non-surgical management strategies were searched with "FAI". Studies which included comparison groups and reported symptom or structural outcomes were included (Levels I-III evidence). A risk of bias assessment was performed. RESULTS: Eighteen studies comparing management strategies for FAI were identified. Most studies had high risk of bias. No study compared surgical and non-surgical treatment. When surgical approaches were compared there was evidence of superior symptom outcomes with arthroscopy compared to open surgery and with labral preservation. There was some evidence that surgical interventions are effective in reducing alpha angle (improved hip shape), but no data on whether this affects long-term outcomes. There was some weak evidence that surgery is associated with structural progression of hip osteoarthritis (OA). CONCLUSIONS: Although evidence supports improvement in symptoms after surgery in FAI, no studies have compared surgical and non-surgical treatment. Therefore no conclusion regarding the relative efficacy of one approach over the other can be made. Surgery improves alpha angle but whether this alters the risk of development or progression of hip OA is unknown. This review highlights the lack of evidence for use of surgery in FAI. Given that hip geometry may be modified by non-surgical factors, clarifying the role of non-surgical approaches vs surgery for the management of FAI is warranted.

Association between serum concentration of 25-hydroxyvitamin D and the risk of hip arthroplasty for osteoarthritis: result from a prospective cohort study.

OBJECTIVES: There is ongoing debate regarding the optimal serum concentrations of 25-hydroxy-vitamin D for musculoskeletal health, including osteoarthritis (OA). The aim of this prospective cohort study was to determine whether serum 25-hydroxy-vitamin D concentrations were associated with the risk of hip arthroplasty for OA. DESIGN: This study examined 9135 participants from the Australian Diabetes, Obesity and Lifestyle Study who had serum 25-hydroxy-vitamin D measured in 1999-2000 and were aged ≥40 years at the commencement of arthroplasty data collection. The incidence of hip arthroplasty for OA during 2002-2011 was determined by linking cohort records to the Australian Orthopaedic Association National Joint Replacement Registry. RESULTS: Over an average 9.1 (standard deviation (SD) 2.7) years of follow-up, 201 hip arthroplasties for OA were identified (males n = 90; females n = 111). In males, a one-standard-deviation increase in 25-hydroxy-vitamin D was associated with a 25% increased incidence (HR 1.25, 95% CI 1.02-1.56), with a dose response relationship evident by quartiles of 25-hydroxy-vitamin D concentration (P for trend 0.04). These results were independent of age, body mass index (BMI), ethnicity, smoking status, physical activity, season of blood collection, latitude, hypertension and diabetes, area level disadvantage or after excluding those with extreme low 25-hydroxy-vitamin D concentrations. No significant association was observed in women (HR 1.10, 95% CI 0.87, 1.39). CONCLUSIONS: Increasing serum 25-hydroxy-vitamin D concentrations were associated with an increased risk of hip arthroplasty for OA in males, while no significant association was observed in females. The mechanism for the association warrants further investigation.

Association between urinary C-telopeptide fragments of type II collagen and knee structure in middle-aged women without clinical knee disease.

OBJECTIVE: There is evidence for an association between levels of urinary C-telopeptide fragments of type II collagen (uCTX-II) and risk of knee osteoarthritis (OA). The aim of this cohort study was to examine the association between uCTX-II levels and knee cartilage and bone changes in middle-aged women without clinical knee disease. DESIGN: 140 women, aged 40-67 years, with no significant knee pain, knee injury or any forms of arthritis, underwent knee magnetic resonance imaging (MRI) at baseline and 2 years later. Cartilage volume, cartilage defects, tibial plateau bone area and bone marrow lesions (BMLs) were measured using validated methods. Baseline uCTX-II was measured using enzyme-linked immunosorbent assay (ELISA). RESULTS: For every one unit (natural logarithm transformed) increase in baseline uCTX-II level, there was an increase in the prevalence of medial tibiofemoral cartilage defects (Odds ratio (OR) 4.36, 95% confidence interval (CI) 1.58-12.04), medial (80.2 mm(2), 95% CI 9.3-151.1) and lateral (86.0 mm(2), 95% CI 33.3-138.7) tibial plateau bone area, and the prevalence of lateral tibiofemoral BMLs (OR 10.62, 95% CI 1.82-61.85). Baseline uCTX-II levels were not significantly associated with baseline tibial cartilage volume or changes in knee cartilage volume or defects or bone area over 2 years, although there was a trend for the deterioration of medial tibiofemoral BMLs (P = 0.06). CONCLUSION: In middle-aged women without clinical knee disease, higher uCTX-II levels were associated with early detrimental structural changes at the knee (cartilage defects, tibial bone expansion and BMLs) at baseline but not over 2 years. Further work will be needed to determine its sensitivity to change and whether it predicts disease progression over longer time periods.

Osteoarthritis bone marrow lesions at the knee and large artery characteristics.

OBJECTIVE: There is evidence to suggest vascular involvement in the initiation and progression of osteoarthritis (OA). The relationship between large artery characteristics and pathogenesis of OA has not been investigated and was the aim of this study. DESIGN: Large artery characteristics (i.e., aortic stiffness, brachial and central blood pressure (BP) variables) and bone marrow lesions (BMLs; measured by magnetic resonance imaging as a surrogate index of OA) were recorded in 208 participants (aged 63 ± 7 years; mean ± SD) with symptomatic knee OA. Relationships between large artery characteristics and BML were assessed by multiple regression adjusting for age, sex and body mass index. RESULTS: There was a high prevalence of BML presence in the study population (70%), but no significant difference between participants with and without BML for all large artery and BP variables (P > 0.05 all). Furthermore, there were no significant relationships between BML size and aortic stiffness (r = -0.033, P = 0.71), central pulse pressure (r = 0.028, P = 0.74), augmentation index (r = 0.125, P = 0.14), brachial pulse pressure (r = 0.005, P = 0.95) or brachial systolic BP (r = -0.066, P = 0.44). When participants were stratified according to high or low aortic stiffness, there was no significant difference between groups regarding the proportion of those with a BML (64% vs. 70% respectively; P = 0.69). CONCLUSIONS: Variables indicative of large artery characteristics are not significantly correlated with BML size or presence in people with symptomatic knee OA. Thus, large artery characteristics may not have a causative influence in the development of OA, but this needs to be confirmed in prospective studies.

Are low levels of low back pain intensity and disability associated with reduced well-being in community-based women?

OBJECTIVES: To examine the relationships between well-being and different levels of both low back pain intensity and disability in women living in the community. METHODS: A detailed, self-administered questionnaire was mailed to 542 community-dwelling women, aged 24-80 years. Participants provided demographic data and completed the Chronic Pain Grade Questionnaire and Psychological General Well-being Index (PGWB). RESULTS: A total of 506 participants (93.4%) returned completed questionnaires. Multivariate analysis revealed associations between lower total PGWB scores and both low (odds ratio (OR) -5.53; 95% confidence interval (CI) -9.01, -2.06) and high pain intensity (OR -8.36; 95% CI -13.8, -2.92) compared with no pain intensity, after adjusting for confounders. Lower total scores on the PGWB were also associated with low (OR -4.72; 95% CI -9.04, -0.41) and high disability (OR -9.26; 95% CI -15.2, -3.30), compared with no disability. There were also statistically significant associations between lower scores on the PGWB subdomains and low and high pain intensities, and low and high disabilities. CONCLUSIONS: We found that it is not only women with high pain intensity and disability who experience reduced well-being, but also those with low levels of pain and disability. Longitudinal investigation is needed to investigate the predictive nature of both low and high levels of pain and disability in determining poor well-being in community-based women.

Bone marrow lesions predict increase in knee cartilage defects and loss of cartilage volume in middle-aged women without knee pain over 2 years.

OBJECTIVE: Bone marrow lesions (BML) are important in established knee osteoarthritis, predicting pain and progression of disease. Whether BML are also associated with longitudinal changes in knee structure in an asymptomatic population is unknown. METHODS: 148 healthy pain-free women in middle age with no history of knee injury or clinical knee osteoarthritis who had a magnetic resonance imaging (MRI) scan performed on their dominant knee at baseline, had another MRI 2 years later to assess whether having a BML present at baseline affected change in tibiofemoral cartilage defects and tibial cartilage volume. RESULTS: BML were present in 14.9% of women at baseline. The risk of progression of total tibiofemoral cartilage defects was significantly higher when a very large BML was present (odds ratio 5.55, 95% CI 1.04 to 29.6) compared with when no BML was present, after adjusting for potential confounders. In the lateral compartment, the rate of cartilage volume loss was significantly greater when a BML was present after adjusting for confounders (regression coefficient 39.2 mm(3), 95% CI 11.1 to 67.2, p = 0.007). CONCLUSIONS: In healthy women without pain at baseline, large BML were associated with both progression of cartilage defects in the whole tibiofemoral joint and more rapid lateral tibial cartilage loss. These data suggest that the relationship between BML and knee cartilage in healthy women is similar to that described in established osteoarthritis. It is possible that BML may predict an increased risk of knee osteoarthritis and facilitate the identification of novel interventions to prevent disease.

Bone marrow lesions predict progression of cartilage defects and loss of cartilage volume in healthy middle-aged adults without knee pain over 2 yrs.

OBJECTIVE: In knee OA, the presence of bone marrow lesions (BMLs) predicts pain and progression of disease. Their occurrence has been described in healthy, pain-free subjects, but whether their presence affects change in cartilage is unknown. METHODS: Two hundred and seventy-one healthy community-dwelling adults with no history of knee injury, knee pain or clinical knee OA had an MRI performed on their dominant knee at baseline and 2 yrs later to assess the relationship between the presence of BMLs at baseline and change in tibiofemoral cartilage defects and tibial cartilage volume over 2 yrs. RESULTS: BMLs were present in 37 (14%) subjects. Cartilage defects were more likely to progress rather than remain stable or regress in subjects with BMLs compared with those without BMLs (P = 0.04). The odds of cartilage defects progressing in the tibiofemoral compartment of the knee where BMLs were present compared with where BMLs were absent was 2.6 (95% CI 1.2, 5.3; P = 0.01). Where 'very large' BMLs were present, there was a trend for increased annual tibial cartilage volume loss (46.4 mm(3)/yr; P = 0.07). CONCLUSIONS: These data suggest that BMLs are associated with change in knee cartilage over 2 yrs in asymptomatic subjects. Increased progression of cartilage defects is seen with increasing size of BMLs. It will be important to determine in future studies whether BMLs directly cause change in cartilage over 2 yrs, or act as a marker of another factor that facilitates these changes.

Tibio-femoral cartilage defects 3-5 years following arthroscopic partial medial meniscectomy.

OBJECTIVE: Arthroscopic partial medial meniscectomy (APMM) is a common procedure to treat a medial meniscal tear. Individuals who undergo APMM have a heightened risk of developing tibio-femoral osteoarthritis (OA). Cartilage defects scored from magnetic resonance imaging (MRI) scans predict cartilage loss over time. It is not known whether cartilage defects in the early years following APMM are more common or of greater severity than in age-matched controls. This study compared the prevalence and severity of tibio-femoral cartilage defects in patients 3-5 years post-APMM with that of age-matched controls. METHODS: Twenty-five individuals who had undergone APMM in the previous 46.9+/-5.0 months and 24 age-matched controls participated in this study. Sagittal plane knee MRI scans were acquired from the operated knees of patients and from randomly assigned knees of the controls and graded (0-4) for tibio-femoral cartilage defects. Defect prevalence (score of >or=2 for any compartment) and severity of the cartilage from both tibio-femoral compartments were compared between the groups. RESULTS: The APMM group had greater prevalence (77 vs 42%, P=0.012) and severity (4.1+/-1.9 vs 2.8+/-1.1, P=0.005) of tibio-femoral cartilage defects than controls. Age was positively associated with tibio-femoral cartilage defect severity for APMM, r=0.523, P=0.007, but not for controls, r=0.045, P=0.834. CONCLUSION: Tibio-femoral joint cartilage defects are more prevalent and of greater severity in individuals who had undergone APMM approximately 44 months earlier than in age-matched controls.

Physician diagnosed arthritis, reported arthritis and radiological non-axial osteoarthritis.

OBJECTIVE: To determine the question that best predicts radiographic evidence of non-axial osteoarthritis (OA). DESIGN: The Melbourne Women's Mid-life Health Project (MWMHP), commenced in 1991, is a population-based prospective study of 438 Australian-born. Two hundred and fifty-seven (57%) women remained in longitudinal assessment in 2002 and 224 (87%) women agreed to undergo X-rays of their hands and knees between 2002 and 2003. METHODS: Annually participants were asked about aches and stiff joints and arthritis or rheumatism. In the eleventh year of follow-up X-rays were scored for evidence of OA using a validated scale, by two investigators who were blinded to questionnaire results. Information on hormone therapy use, physical activity, mood, smoking, body mass index (BMI) and age were obtained by both self-administered and face-to-face questionnaires. RESULTS: Patient reported physician diagnosed arthritis was the best predictor of radiological OA (ROA). The question had a specificity of 64%, a positive predictive value of 57% and a negative predictive value of 71%. Even the most reliable question about arthritis still had a relatively low specificity for radiologically diagnosed OA. Reporting symptoms were significantly more common in participants who were depressed, those who had a higher negative affect and those with a higher BMI. CONCLUSION: In large epidemiological studies where questionnaire assessment of OA is required, the greatest accuracy is achieved by asking about physician diagnosed arthritis. Concurrent application of a validated scale for mood is important.

Meniscal tear and increased tibial plateau bone area in healthy post-menopausal women.

OBJECTIVE: Meniscal tears detected using magnetic resonance imaging (MRI) have been identified as a risk factor for the development and progression of Osteoarthritis, however the prevalence and significance of meniscal tears in healthy, asymptomatic adults remains to be studied. We investigated the prevalence of meniscal tears in a healthy pain free population of post-menopausal women and whether meniscal tears in this population are associated with changes in cartilage volume and defects and tibial plateau bone area over 2 years. METHODS: Fifty-seven post-menopausal women underwent MRI of their dominant knee at baseline line and approximately 2 years later to assess meniscal tears, cartilage volume, cartilage defects and tibial plateau bone area. RESULTS: Forty-six percent of women had a meniscal tear in either the medial and/or lateral compartment. Women who had a tear were older (P=0.01) and had more lateral cartilage defects (P=0.02). Medial meniscal tear was associated with 103 mm(2) greater tibial plateau bone area within the medial [95% confidence of interval (CI) 6.2, 200.3; P=0.04] and a lateral meniscal tear with a 120 mm(2) greater area within the lateral compartment (95% CI 45.5, 195.2; P=0.002). CONCLUSION: This study demonstrates that meniscal tears are common in asymptomatic post-menopausal women and that they become more common with age. Meniscal tears were also associated with greater tibial plateau bone area but not cartilage volume, providing support to the hypothesis that tibial plateau bone changes occur before significant pathological changes in cartilage. Whether increased tibial plateau bone area predisposes to an increased risk of degenerative meniscal tears or whether it is a consequence of altered biomechanical forces in relation to meniscal tear will need to be determined.

Effect of fatty acids on bone marrow lesions and knee cartilage in healthy, middle-aged subjects without clinical knee osteoarthritis.

OBJECTIVE: There is evidence that omega-3 polyunsaturated fatty acids alleviate the progression of osteoarthritis (OA). However, little work has been done to investigate the effect of fatty acids on bone marrow lesions and knee cartilage in healthy subjects. We examined this in a cohort of healthy middle-aged subjects without clinical knee OA. METHODS: Two hundred and ninety-three healthy adults without knee pain or injury were recruited from an existing community-based cohort. Intakes of fatty acids and food sources of these were estimated from a food frequency questionnaire at baseline. Tibial cartilage volume, tibial plateau bone area, tibiofemoral cartilage defects and bone marrow lesions were assessed approximately 10 years later using magnetic resonance imaging. RESULTS: In multivariate analyses, higher intakes of monounsaturated fatty acids (OR=2.14, 95% CI 1.04-4.39, P=0.04), total (OR=1.77, 95% CI 1.13-2.77, P=0.01) and n-6 polyunsaturated fatty acids (OR=1.69, 95% CI 1.10-2.61, P=0.02) were associated with an increased risk of bone marrow lesions. Intake of fatty acids was not significantly associated with cartilage volume or cartilage defects. CONCLUSION: These findings support the dietary recommendation towards a shift to foods rich in n-3 polyunsaturated fatty acids in order to maintain an optimal balance between dietary n-3 and n-6 polyunsaturated fatty acids, which is also important in the prevention of atherosclerosis. Although our findings will need to be confirmed in longitudinal studies, they suggest the potential of fatty acids to adversely effect the knee joint.

The natural history of cartilage defects in people with knee osteoarthritis.

OBJECTIVES: Cartilage defects are highly prevalent in subjects with knee osteoarthritis (OA). Although they are associated with increased cartilage loss and joint replacement, there is little data on the natural history of cartilage defects. The aim of this study was to examine the progression of cartilage defects over 2 years in people with knee OA and to identify factors associated with progression. METHODS: One hundred and seventeen subjects with OA underwent magnetic resonance imaging of their dominant knee at baseline and follow-up. Cartilage defects were scored (0-4) at four sites. Bone size of the medial and lateral tibial plateau was determined. Height, weight, body mass index and physical activity were measured by standard protocols. RESULTS: The mean cartilage defect score increased significantly over the 2-year study period in all tibiofemoral compartments (all P<0.001), except the lateral tibial compartment with age and tibial plateau bone area at baseline being predictors of progression. However, there was heterogeneity with 81% progressing at any site, 15% remaining stable and 4% decreasing. CONCLUSION: Over 2 years, cartilage defects tend to progress in people with symptomatic OA, with only a small percentage decreasing in severity. Increasing age and increased bone area are risk factors for progression. Interventions aimed at preventing cartilage defects from occurring and reducing their severity may result in a reduction in the severity of OA, by reducing loss of articular cartilage and subsequent requirement for knee joint replacement.