Is increased joint loading detrimental to obese patients with knee osteoarthritis? A secondary data analysis from a randomized trial

SummaryObjectiveTo investigate whether increased knee joint loading due to improved ambulatory function and walking speed following weight loss achieved over 16 weeks accelerates symptomatic and structural disease progression over a subsequent 1 year weight maintenance period in an obese population with knee osteoarthritis (OA).MethodsData from a prospective study of weight loss in obese patients with knee OA (the CARtilage in obese knee OsteoarThritis (CAROT) study) were used to determine changes in knee joint compressive loadings (model estimated) during walking after a successful 16 week weight loss intervention. The participants were divided into ‘Unloaders’ (participants that reduced joint loads) and ‘Loaders’ (participants that increased joint loads). The primary symptomatic outcome was changes in knee symptoms, measured with the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire, during a subsequent 52 weeks weight maintenance period. The primary structural outcome was changes in tibiofemoral cartilage loss assessed semi-quantitatively (Boston Leeds Knee Osteoarthritis Score (BLOKS) from MRI after the 52 weight maintenance period.Results157 participants (82% of the CAROT cohort) with medial and/or lateral knee OA were classified as Unloaders (n = 100) or Loaders (n = 57). The groups showed similar significant changes in symptoms (group difference: −2.4 KOOS points [95% CI −6.8:1.9]) and cartilage loss (group difference: −0.06 BLOKS points [95% CI −0.22:0.11) after 1 year, with no statistically significant differences between Loaders and Unloaders.ConclusionFor obese patients undergoing a significant weight loss, increased knee joint loading for 1 year was not associated with accelerated symptomatic and structural disease progression compared to a similar weight loss group that had reduced ambulatory compressive knee joint loads.Clinicaltrials.govNCT00655941

Changes in bone marrow lesions in response to weight-loss in obese knee osteoarthritis patients: a prospective cohort study

BACKGROUND: Patients are susceptible for knee osteoarthritis (KOA) with increasing age and obesity and KOA is expected to become a major disabling disease in the future. An important feature of KOA on magnetic resonance imaging (MRI) is changes in the subchondral bone, bone marrow lesions (BMLs), which are related to the future degeneration of the knee joint as well as prevalent clinical symptoms. The aim of this study was to investigate the changes in BMLs after a 16-week weight-loss period in obese subjects with KOA and relate changes in BMLs to the effects of weight-loss on clinical symptoms. METHODS: This prospective cohort study included patients with a body mass index ≥ 30 kg/m(2), an age ≥ 50 years and primary KOA. Patients underwent a 16 weeks supervised diet program which included formula products and dietetic counselling (ClinicalTrials.gov: NCT00655941). BMLs in tibia and femur were assessed on MRI before and after the weight-loss using the Boston-Leeds Osteoarthritis Knee Score. Response to weight-loss in BML scores was dichotomised to patients experiencing a decrease in BML scores (responders) and patients who did not (non-responders). The association of BMLs to weight-loss was assessed by logistic regressions and correlation analyses. RESULTS: 39 patients (23%) were classified as responders in the sum of all BML size scores whereas 130 patients (77%) deteriorated or remained stable and were categorized as non-responders. Logistic regression analyses revealed no association between weight-loss < or ≥ 10% and response in BMLs in the most affected compartment (OR 1.86 [CI 0.66 to 5.26, p=0.24]). There was no association between weight-loss and response in maximum BML score (OR 1.13 [CI 0.39 to 3.28, p=0.81]). The relationship between changes in BMLs and clinical symptoms revealed that an equal proportion of patients classified as BML responders and non-responders experienced an OMERACT-OARSI response (69 vs. 71%, p=0.86). CONCLUSIONS: Weight-loss did not improve the sum of tibiofemoral BML size scores or the maximum tibiofemoral BML score, suggesting that BMLs do not respond to a rapidly decreased body weight. The missing relationship between clinical symptoms and BMLs calls for further investigation

Radiographs and low field MRI (0.2T) as predictors of efficacy in a weight loss trial in obese women with knee osteoarthritis

<p>Abstract</p> <p>Background</p> <p>To study the predictive value of baseline radiographs and low-field (0.2T) MRI scans for the symptomatic outcome of clinically significant weight loss in obese patients with knee osteoarthritis.</p> <p>Methods</p> <p>In this study we hypothesize that imaging variables assessed with radiographs and MRI scans pre-treatment can predict the symptomatic changes following a recommended clinically significant weight reduction Patients were recruited from the Department of Rheumatology, Frederiksberg Hospital, Denmark. Eligibility criteria were: age >18 years; primary osteoarthritis according to ACR; BMI > 28 kg/m2; motivation for weight loss. Subjects were randomly assigned to either intervention by low-energy diet (LED) for 8 weeks followed by another 24 weeks of dietary instruction or control-group. MRI scans and radiographs were scored for structural changes and these parameters were examined as independent predictors of changes in osteoarthritis symptoms after 32 weeks. The outcome assessor and statistician were blinded to group allocation.</p> <p>Results</p> <p>No significant correlations were found between imaging variables and changes in Western Ontario and McMaster Universities Index of Osteoarthritis (Spearman's test, r < 0.33 and P > 0.07).</p> <p>Only the LED group achieved a weight loss, with a mean difference of 16.3 kg (95%CI: 13.4-19.2;P < 0.0001) compared to the control group. The total WOMAC index showed a significant difference favouring LED, with a group mean difference of - 321.3 mm (95%CI: -577.5 to -65.1 mm; P = 0.01). No significant adverse events were reported.</p> <p>Conclusion</p> <p>Stage of joint destruction, assessed on either radiographs or low-field MRI (0.2T), does not preclude a symptoms relief following a clinically relevant weight loss in elderly obese female patients with knee osteoarthritis.</p

A systematic review of the relationship between subchondral bone features, pain and structural pathology in peripheral joint osteoarthritis

Introduction: Bone is an integral part of the osteoarthritis (OA) process. We conducted a systematic literature review in order to understand the relationship between non-conventional radiographic imaging of subchondral bone, pain, structural pathology and joint replacement in peripheral joint OA. Methods: A search of the Medline, EMBASE and Cochrane library databases was performed for original articles reporting association between non-conventional radiographic imaging-assessed subchondral bone pathologies and joint replacement, pain or structural progression in knee, hip, hand, ankle and foot OA. Each association was qualitatively characterised by a synthesis of the data from each analysis based upon study design, adequacy of covariate adjustment and quality scoring. Results: In total 2456 abstracts were screened and 139 papers were included (70 cross-sectional, 71 longitudinal analyses; 116 knee, 15 hip, six hand, two ankle and involved 113 MRI, eight DXA, four CT, eight scintigraphic and eight 2D shape analyses). BMLs, osteophytes and bone shape were independently associated with structural progression or joint replacement. BMLs and bone shape were independently associated with longitudinal change in pain and incident frequent knee pain respectively. Conclusion: Subchondral bone features have independent associations with structural progression, pain and joint replacement in peripheral OA in the hip and hand but especially in the knee. For peripheral OA sites other than the knee, there are fewer associations and independent associations of bone pathologies with these important OA outcomes which may reflect fewer studies; for example the foot and ankle were poorly studied. Subchondral OA bone appears to be a relevant therapeutic target. Systematic review: PROSPERO registration number: CRD 4201300500

Structural changes in the knee during weight loss maintenance after a significant weight loss in obese patients with osteoarthritis: a report of secondary outcome analyses from a randomized controlled trial.

To compare structural knee joint changes in obese patients with knee osteoarthritis (OA) that after an intensive weight loss therapy were randomized to continuous dietetic support, a specialized knee exercise program, or 'no attention' for 1 year

An ultrasound score for knee osteoarthritis: a cross-sectional validation study

SummaryObjectiveTo develop standardized musculoskeletal ultrasound (MUS) procedures and scoring for detecting knee osteoarthritis (OA) and test the MUS score's ability to discern various degrees of knee OA, in comparison with plain radiography and the ‘Knee injury and Osteoarthritis Outcome Score’ (KOOS) domains as comparators.MethodA cross-sectional study of MUS examinations in 45 patients with knee OA. Validity, reliability, and reproducibility were evaluated.ResultsMUS examination for knee OA consists of five separate domains assessing (1) predominantly morphological changes in the medial compartment, (2) predominantly inflammation in the medial compartment, (3) predominantly morphological changes in the lateral compartment, (4) predominantly inflammation in the lateral compartment, and (5) effusion. MUS scores displayed substantial reliability and reproducibility, with interclass correlations coefficients ranging from 0.75 to 0.97 for the five domains. Construct validity was confirmed with statistically significant correlation coefficients (0.47–0.81, P < 0.01).ConclusionThe MUS score suggested in this study was reliable and valid in detecting knee OA. In comparison with standing radiographs of the knees, the score detected all aspects of knee OA with relevant precision