Change In Cartilage Volume Research Articles

Metabolic triggered inflammation in osteoarthritis

Obesity is arguably the most important modifiable risk factor for onset, progression and symptoms of knee osteoarthritis (OA). For many years the association of obesity and OA has been simply attributed to the effects of overload on weight-bearing joints. There is now a growing body of evidence that obesity is a complex syndrome in which the abnormal activation of endocrine and pro-inflammatory pathways. This metabolic triggered inflammation may play an important role in the pathogenesis of OA. Activated adipose tissue produces adipokines including leptin, adiponectin, resistin and visfatin, and increases the synthesis of pro-inflammatory cytokines, such as IL-6 and tumor necrosis factor (TNF)-α. Leptin can up-regulate collagenase matrix metalloproteinase (MMP) −13 and induce inflammation, thus may play a significant role in OA. We reported that serum levels of leptin were associated with reduced knee cartilage volume and increased hip radiographic joint space narrowing. The positive association between BMI and knee cartilage volume disappeared, and positive associations between body fat and knee cartilage volume decreased in magnitude, after adjustment for leptin. Similarly, the positive association between BMI, body fat and hip joint space narrowing disappeared after adjustment for leptin. Furthermore, we reported that higher baseline IL-6 levels were associated with greater radiographic OA, and predicted greater loss of knee cartilage volume. Change in IL-6 was also associated with change in cartilage volume. Additionally, higher baseline TNF-α levels were associated with greater radiographic OA, and change in TNF-α was associated with change in cartilage volume. These preliminary results from clinical and epidemiological studies suggest metabolic and inflammatory mechanisms play roles in the pathogenesis of OA and may also mediate the effects of obesity on OA. Further studies are required to elucidate comprehensively the roles of other adipokines/cytokines in OA.

Higher dynamic medial knee load predicts greater cartilage loss over 12 months in medial knee osteoarthritis

ObjectiveMechanical factors, in particular increased medial knee joint load, are believed to be important in the structural progression of knee osteoarthritis. This study evaluated the relationship of medial knee load...

Association of Baseline Knee Bone Size, Cartilage Volume, and Body Mass Index with Knee Cartilage Loss Over Time: A Longitudinal Study in Younger or Middle-aged Adults

To determine the association of knee bone size, cartilage volume, and body mass index (BMI) at baseline with knee cartilage loss over 2 years in younger or middle-aged adults. A total of 324 subjects (mean age 45 yrs, range 26-61) were measured at baseline and about 2 years later. Knee cartilage volume and bone size were determined using T1-weighted fat-saturated magnetic resonance imaging. In multivariable analysis, baseline knee bone size was negatively associated with annual change in knee cartilage volume at medial and lateral tibial sites (ß = -0.62% to -0.47%/cm(2), all p < 0.001). The associations disappeared at medial tibial site after adjustment for baseline cartilage volume and became of borderline statistical significance at lateral tibial site after adjustment for both baseline cartilage volume and osteophytes (ß = -0.29, p = 0.059). Baseline knee cartilage volume was consistently and negatively associated with annual change in knee cartilage volume at all 3 medial tibial, lateral tibial, and patellar sites (ß = -4.41% to -1.37%/ml, all p < 0.001). Baseline BMI was negatively associated with an annual change in knee cartilage volume, but only in subjects within the upper tertile of baseline cartilage volume, even after adjusting for cartilage defects (ß = -0.16% to -0.34%/kg/m(2), all p < 0.05). Our study suggests that both higher baseline tibial bone area and knee cartilage volume (most likely due to cartilage swelling) are associated with greater knee cartilage loss over 2 years. A higher BMI was associated with greater knee cartilage loss only in subjects with higher baseline cartilage volume.

Lateral wedge insoles for medial knee osteoarthritis: 12 month randomised controlled trial

Objective To assess the effect of lateral wedge insoles compared with flat control insoles on improving symptoms and slowing structural disease progression in medial knee osteoarthritis.Design Randomised controlled trial.Setting Community...

Deformational behaviour of knee cartilage and changes in serum cartilage oligomeric matrix protein (COMP) after running and drop landing

To investigate (1) the effect of running and drop landing interventions on knee cartilage deformation and serum cartilage oligomeric matrix protein (COMP) concentration and (2) if the changes in cartilage volume correlate with the changes in serum COMP level. Knee joint cartilage volume and thickness were determined using magnetic resonance imaging (MRI) as well as COMP concentration from serum samples before and after in vivo loading of 14 healthy adults (seven male and seven female). Participants performed different loading interventions of 30 min duration on three different days: (1) 100 vertical drop landings from a 73 cm high platform, (2) running at a velocity of 2.2m/s (3.96 km), and (3) resting on a chair. Blood samples were taken immediately before, immediately after and 0.5h, 1h, 2h and 3h post intervention. Pre- and post-loading coronal and axial gradient echo MR images with fat suppression were used to determine the patellar, tibial and femoral cartilage deformation. Serum COMP levels increased immediately after the running (+30.7%, pre: 7.3U/l, 95% confidence interval (CI): 5.6, 8.9, post: 9.1U/l, 95% CI: 7.2, 11.0, P=0.001) and after drop landing intervention (+32.3%, pre: 6.8U/l, 95% CI: 5.3, 8.4; post: 8.9U/l, 95% CI: 6.8, 10.9, P=0.001). Cartilage deformation was more pronounced after running compared to drop landing intervention, with being significant (volume: P=0.002 and thickness: P=0.001) only in the lateral tibia. We found a significant correlation (r(2)=0.599, P=0.001) between changes in serum COMP (%) and in cartilage volume (%) after the drop landing intervention, but not after running. In vivo exercise interventions differentially regulate serum COMP concentrations and knee cartilage deformations. The relation between changes in COMP and in cartilage volume seems to depend on both mechanical and biochemical factors.

Risk factors predictive of joint replacement in a 2-year multicentre clinical trial in knee osteoarthritis using MRI: results from over 6 years of observation

ObjectiveTo identify predictive factors for total knee replacement (TKR) using data from MRI of knee osteoarthritis patients in a phase III multicentre disease-modifying osteoarthritis drug (DMOAD) study.MethodsKnee osteoarthritis patients from...

Systematic review of the concurrent and predictive validity of MRI biomarkers in OA

To summarize literature on the concurrent and predictive validity of MRI-based measures of osteoarthritis (OA) structural change. An online literature search was conducted of the OVID, EMBASE, CINAHL, PsychInfo and Cochrane databases of articles published up to the time of the search, April 2009. 1338 abstracts obtained with this search were preliminarily screened for relevance by two reviewers. Of these, 243 were selected for data extraction for this analysis on validity as well as separate reviews on discriminate validity and diagnostic performance. Of these 142 manuscripts included data pertinent to concurrent validity and 61 manuscripts for the predictive validity review. For this analysis we extracted data on criterion (concurrent and predictive) validity from both longitudinal and cross-sectional studies for all synovial joint tissues as it relates to MRI measurement in OA. Concurrent validity of MRI in OA has been examined compared to symptoms, radiography, histology/pathology, arthroscopy, CT, and alignment. The relation of bone marrow lesions, synovitis and effusion to pain was moderate to strong. There was a weak or no relation of cartilage morphology or meniscal tears to pain. The relation of cartilage morphology to radiographic OA and radiographic joint space was inconsistent. There was a higher frequency of meniscal tears, synovitis and other features in persons with radiographic OA. The relation of cartilage to other constructs including histology and arthroscopy was stronger. Predictive validity of MRI in OA has been examined for ability to predict total knee replacement (TKR), change in symptoms, radiographic progression as well as MRI progression. Quantitative cartilage volume change and presence of cartilage defects or bone marrow lesions are potential predictors of TKR. MRI has inherent strengths and unique advantages in its ability to visualize multiple individual tissue pathologies relating to pain and also predict clinical outcome. The complex disease of OA which involves an array of tissue abnormalities is best imaged using this imaging tool.

Lateral wedge shoe insoles for medial knee osteoarthritis: a 12‐month randomised controlled trial

Methods A randomised participant- and assessor-blinded controlled trial was used. 200 people aged 50 or more with clinical and radiographic diagnosis of mild-to-moderately severe medial knee OA were recruited. The interventions consisted of full-length 5° lateral wedged insoles or flat control insoles worn inside the shoes daily for 12 months. The primary symptomatic outcome was change in overall knee pain (past week) measured on an 11-point numeric rating scale and primary structural outcome was change in medial tibial cartilage volume from magnetic resonance imaging. Secondary clinical outcomes included changes in measures of pain, function, stiffness, and health-related quality of life. Secondary structural outcomes included progression of medial cartilage defects and bone marrow lesions. Results There were no significant between-group differences for the primary outcomes of change in overall pain (-0.3 points 95% CI (-1.0 to 0.3)) and change in medial tibial

Quantification of cartilage loss in local regions of knee joints using semi-automated segmentation software: analysis of longitudinal data from the Osteoarthritis Initiative (OAI)

Quantitative cartilage morphometry is a valuable tool to assess osteoarthritis (OA) progression. Current methodologies generally evaluate cartilage morphometry in a full or partial sub-region of the cartilage plates. This report describes the evaluation of a semi-automated cartilage segmentation software tool capable of quantifying cartilage loss in a local indexed region. We examined the baseline and 24-month follow-up MRI image sets of twenty-four subjects from the progression cohort of Osteoarthritis Initiative (OAI), using the Kellgren-Lawrence (KL) score of 3 at baseline as the inclusion criteria. A radiologist independently marked a single region of local thinning for each subject, and three additional readers, blinded to time point, segmented the cartilage using a semi-automated software method. Each baseline-24-month segmentation pair was then registered in 3D and the change in cartilage volume was measured. After 3D registration, the change in cartilage volume was calculated in specified regions centered at the marked point, and for the entire medial compartment of femur. The responsiveness was quantified using the standardized response mean (SRM) values and the percentage of subjects that showed a loss in cartilage volume. The most responsive measure of change was SRM=-1.21, and was found for a region of 10mm from the indexed point. The results suggest that measurement of cartilage loss in a local region is superior to larger areas and to the total plate. There also may be an optimal region size (10mm from an indexed point) in which to measure change. In principle, the method is substantially faster than segmenting entire plates or sub-regions.

Bone marrow lesions in people with knee osteoarthritis predict progression of disease and joint replacement: a longitudinal study

The presence of bone marrow lesions (BMLs) has been linked to pain and progression of knee OA. The aim of this study was to determine the relationship between BMLs and longitudinal change in tibial cartilage volume and risk of knee joint replacement in subjects with knee OA. One hundred and nine men and women with symptomatic knee OA were recruited. The same knee was imaged using MRI at baseline and ∼2 years later. Tibial cartilage volume and BMLs were measured. Knee joint replacement over 4 years was determined. The mean age of the subjects at baseline was 63.2 (s.d. 10.3) years. BMLs were present in 66% of the subjects. Cross-sectionally, BMLs were negatively associated with both medial (regression coefficient -121.4; 95% CI -183.8, -859.1; P<0.001) and lateral (regression coefficient -142.1; 95% CI -241.8, -42.4; P=0.01) tibial cartilage volume data. Longitudinally, for every 1-score increase in baseline BML severity (range 0-4), the annual total tibial cartilage loss was increased by 1.14% (95% CI 0.29%, 1.87%; P=0.01). The risk of knee joint replacement over 4 years increased with increasing BML score (odds ratio 1.57; 95% CI 1.04, 2.35; P=0.03). The prevalence and severity of BMLs are associated with less tibial cartilage volume and greater cartilage loss over 2 years. Moreover, severity of BMLs was positively associated with risk of knee joint replacement over 4 years. This provides further support for the importance of BMLs in identifying those with OA most likely to progress. Identifying factors that prevent or reduce the severity of BMLs may provide an important target in the prevention of disease progression and treatment of OA, and the subsequent need for arthroplasty.

Circulating levels of IL-6 and TNF-α are associated with knee radiographic osteoarthritis and knee cartilage loss in older adults

The role of inflammation in osteoarthritis (OA) pathogenesis is unclear, and the associations between inflammatory cytokines and cartilage loss have not been reported. We determined the associations between serum levels of interleukin (IL)-6 and tumor necrosis factor-α (TNF-α), knee radiographic OA (ROA) and cartilage loss over 2.9 years in older adults. A total of 172 randomly selected subjects (mean 63 years, range 52-78, 47% female) were studied at baseline and approximately 3 (range 2.6-3.3) years later. IL-6 and TNF-α were assessed by radioimmunoassay. T1-weighted fat-suppressed magnetic resonance imaging of the right knee was performed at baseline and follow-up to determine knee cartilage volume. Knee ROA of both knees was assessed at baseline. At baseline, quartiles of IL-6 and TNF-α were associated with increased prevalence of medial tibiofemoral joint space narrowing (OARSI grade ≥ 1) in multivariate analyses [odds ratio (OR): 1.42 and 1.47 per quartile, respectively, both P<0.05]. Longitudinally, baseline IL-6 predicted loss of both medial and lateral tibial cartilage volume (β: -1.19% and -1.35% per annum per quartile, P<0.05 and P<0.01, respectively), independently of TNF-α. Change in IL-6 was associated with increased loss of medial and lateral tibial cartilage volume (β: -1.18% and -1.06% per annum per quartile, both P<0.05) and change in TNF-α was also negatively associated with change in medial cartilage volume (β: -1.27% per annum per quartile, P<0.05). Serum levels of IL-6 and TNF-α are associated with knee cartilage loss in older people suggesting low level inflammation plays a role in the pathogenesis of knee OA.

Women lose patella cartilage at a faster rate than men: A 4.5-year cohort study of subjects with knee OA

Objectives Patellofemoral knee osteoarthritis (OA) is a common disease, and a significant cause of knee pain, however few data have examined longitudinal change at the patellofemoral joint. The aim of this study was to examine factors affecting change in patella cartilage over a longer time period than previously examined. Study design Longitudinal study of 77 subjects (58% female) with knee OA underwent magnetic resonance imaging (MRI), with a repeat MRI of the same knee obtained approximately 4.5 years later. Main outcome measures Annual change in patella cartilage volume, and annual percentage change over 4.5 years. Results After adjusting for age, gender, BMI and patella bone volume at baseline, cartilage change was observed at the rate of 2.5% (95% confidence interval, 2.0, 3.0) per annum over 4.5 years. Cartilage was lost at a higher rate in women compared to men after accounting for age, BMI or bone volume at baseline (3.3% vs. 1.4%, respectively, p = 0.03). Increased patella bone volume was associated with increased patella cartilage loss ( p = 0.02). No measures of radiographic severity of disease affected change in cartilage volume. Conclusions The increased rate of cartilage loss in women may contribute to the increased prevalence of disease, although the underlying mechanism requires further study. Increased patella bone volume was also associated with increased patella cartilage loss. Whether this is due to biomechanical factors will need to be determined.

Relationship between bone marrow lesions, cartilage loss and pain in knee osteoarthritis: results from a randomised controlled clinical trial using MRI

ObjectiveTo assess in a multicentre randomised double-blind phase III clinical trial evaluating the effect of licofelone in comparison with naproxen on knee osteoarthritis (OA) the presence of, and change in,...

Relationship of serum markers of cartilage metabolism to imaging and clinical outcome measures of knee joint structure

BackgroundBiomarkers of cartilage metabolism have prognostic potential.ObjectiveTo examine whether serum cartilage biomarkers, cartilage oligomeric matrix protein (COMP), N-propeptide of type IIA procollagen (PIIANP), type II collagen breakdown product (collagen type-II...

Markers of Bone Formation and Resorption Identify Subgroups of Patients with Clinical Knee Osteoarthritis Who Have Reduced Rates of Cartilage Loss

To determine whether serum markers of bone formation and resorption, used individually or in combination, can be used to identify subgroups who lose cartilage volume at different rates over 2 years within a knee osteoarthritis (OA) population. Changes in cartilage volume over 2 years were measured in 117 subjects with knee OA using magnetic resonance imaging. We examined relationships between change in cartilage volume and baseline serum markers of bone formation [intact N-terminal propeptide of type I procollagen (PINP) and osteocalcin] and resorption [N-telopeptide of type I collagen (NTX-I), C-telopeptide of type I collagen (CTX-I), and C-telopeptide of type I collagen (ICTP). The baseline markers of bone formation, PINP and osteocalcin (p = 0.02, p = 0.01, respectively), and the baseline markers of bone resorption, CTX-I and NTX-I (p = 0.02 for both), were significantly associated with reduced cartilage loss. There were no significant associations between baseline ratios of bone formation to resorption markers and cartilage loss. However, when subjects were divided into subgroups with high or low bone formation markers (based on levels of marker >or= mean or < mean for the population, respectively), in the subgroup with high PINP there was a significant association between increasing bone resorption markers CTX-I and NTX-I and reduced cartilage loss (p = 0.02, p = 0.001, respectively). Similarly, in the subgroup with high osteocalcin, there was a significant association between increasing CTX-I and NTX-I and reduced cartilage loss (p = 0.02, p = 0.003, respectively). In contrast, in subgroups with low bone formation markers, no significant associations were obtained between markers of bone resorption and cartilage loss. Overall, the results suggest that higher bone remodeling (i.e., higher serum levels of bone formation and resorption) is associated with reduced cartilage loss. Considering markers of bone formation and resorption together, it is possible to identify subgroups within the OA population who have reduced rates of cartilage loss.

Do NSAIDs Affect Longitudinal Changes in Knee Cartilage Volume and Knee Cartilage Defects in Older Adults?

Background The effects of nonsteroidal anti-inflammatory drugs (NSAIDs) on knee osteoarthritis progression are unclear. The aim of this longitudinal study was to determine the associations between use of NSAIDs and changes in knee cartilage volume and knee cartilage defects over 2.9 years in older adults. Methods T 1-weighted fat-suppressed magnetic resonance imaging on the right knee was performed in a total of 395 randomly selected subjects (mean age 62 years, range 51-80 years, and 50% female) to assess knee cartilage volume at tibial sites and knee cartilage defects (0-4 scale) at baseline and 2.9 years later. Medication use in the last month was recorded by questionnaire. Results Compared with nonusers of NSAIDs (n = 334), users of cyclooxygenase (COX)-2 inhibitors (n = 40) had decreased knee cartilage defect development in the medial tibiofemoral compartment (odds ratio [OR] 0.4, 95% confidence interval [CI], 0.2-0.99), whereas users of conventional NSAIDs (n = 21) had increased knee cartilage defect development in both medial (OR 3.1, 95% CI, 1.0-9.1) and lateral (OR 2.6, 95% CI, 1.0-6.7) tibiofemoral compartments. Comparing users of COX-2 inhibitors with users of conventional NSAIDs, the latter had higher knee cartilage volume loss (−5.3% vs −3.1% at medial tibia and −3.6% vs −1.1% at lateral tibia; all P <.05). All associations were adjusted for potential confounders including knee pain and radiographic osteoarthritis. Conclusions This study suggests that nonselective NSAIDs may have deleterious effects, while selective COX-2 inhibitors might have beneficial effects on knee cartilage. Randomized controlled trials examining knee structure to confirm this finding are warranted.

Longitudinal effect of vigorous physical activity on patella cartilage morphology in people without clinical knee disease

There are few data concerning possible long-term effects of physical activity on cartilage change in the patellofemoral compartment. We examined the effect of participation in vigorous physical activity on changes to patella cartilage over 2 years. A total of 297 healthy adults ages 50-79 years with no history of knee injury or symptoms were recruited from an existing study. Physical activity data were obtained by questionnaire at baseline (2003-2004). Patella cartilage volume and defects were determined by magnetic resonance imaging at baseline (2003-2004) and followup (2006-2007). Participation in vigorous physical activity at baseline was associated with a reduced rate of patella cartilage volume loss (-21.2 mm(3) per annum [95% confidence interval (95% CI) -41.5, -1.0; P = 0.04]) and a trend toward less risk of worsening patella cartilage defects (odds ratio 0.4; 95% CI 0.2, 1.1 [P = 0.07]) over the subsequent 2 years. In the subgroup with no significant patella cartilage defects at baseline (n = 192), participation in vigorous physical activity was associated with a reduced annual rate of patella cartilage volume loss (95% CI -53.8, -7.8; P = 0.03) and a trend for fewer new patella cartilage defects (95% CI 0.1, 1.1; P = 0.08). No significant relationships were found between vigorous physical activity and cartilage volume change or defect progression in the subgroup with prevalent patella cartilage defects at baseline. These observations suggest that vigorous physical activity is beneficial to patellofemoral joints for people without preexisting cartilage damage. Weight-bearing vigorous physical activity might, therefore, be useful in the prevention of patellofemoral osteoarthritis.

Women have increased rates of cartilage loss and progression of cartilage defects at the knee than men

Women have an increased risk of knee osteoarthritis (OA). However, little is known about gender differences in cartilage health before the onset of clinical knee OA. The aim of this study was to examine whether there are longitudinal gender differences in knee cartilage in a cohort of healthy, asymptomatic adults with no clinical knee disease. Two hundred seventy-one participants (169 women) aged between 50 and 79 years with no clinical history of knee pain or pathology were examined using magnetic resonance imaging at baseline and 2.3 years later. From these images, changes in tibial and patella cartilage volume and progression of cartilage defects were determined. In multivariate analyses, after adjustment for potential confounders, the average annual percentage loss of total tibial cartilage volume was significantly greater in women (1.6% [95% CI, 1.1-2.2]) than in men (0.4%[95% CI, -0.4 to 1.2]) (P = 0.05 for difference). Likewise, the female gender was also associated with an increased risk for the progression of tibiofemoral cartilage defects (odds ratio, 3.0; 95% CI, 1.1-8.1; P = 0.03). At the patella,the average annual percentage loss of cartilage volume was significantly greater in women (2.3% [95% CI, 1.7-2.8]) than in men (0.8% [95% CI, 0.1-1.6]) (P = 0.02 for difference). The female predisposition toward knee OA may, at least in part, be due to gender differences in cartilage health, even before the onset of clinical knee disease. Understanding the mechanism for these gender differences may provide a means to reduce the risk of knee OA in women.

Serum levels of vitamin D, sunlight exposure, and knee cartilage loss in older adults: The Tasmanian older adult cohort study

To determine the associations between serum levels of vitamin D, sunlight exposure, and knee cartilage loss cross-sectionally and longitudinally in older adults. A total of 880 randomly selected subjects (mean age 61 years [range 51-79 years], 50% women) were studied at baseline, and 353 of these subjects were studied 2.9 years later. Serum levels of 25-hydroxyvitamin D (25[OH]D) were assessed by radioimmunoassay, and sunlight exposure was assessed by questionnaire. T1-weighted fat-suppressed magnetic resonance imaging (MRI) of the right knee was performed to determine knee cartilage volume and defects. Knee radiographic osteoarthritis (OA) and knee pain were also assessed. The mean 25(OH)D serum level was 52.8 nmoles/liter at baseline (range 13-119 nmoles/liter). Winter sunlight exposure and serum 25(OH)D level were both positively associated with medial and lateral tibial cartilage volume, and a serum 25(OH)D level<50 nmoles/liter was associated with increased medial tibiofemoral joint space narrowing (all P<0.05). Longitudinally, baseline serum 25(OH)D level predicted change in both medial and lateral tibial cartilage volume (beta=+0.04% per annum per nmole/liter for both; P<0.05), and change in serum 25(OH)D level was positively associated with change in medial tibial cartilage volume. These associations were consistent in subjects with radiographic OA and knee pain and/or in women, but not in men or in subjects without radiographic OA or knee pain. Sunlight exposure and serum 25(OH)D levels are both associated with decreased knee cartilage loss (assessed by radiograph or MRI). This is best observed using the whole range of 25(OH)D levels rather than predefined cut points and implies that achieving vitamin D sufficiency may prevent and/or retard cartilage loss in knee OA.

The short-term effects of running on the deformation of knee articular cartilage and its relationship to biomechanical loads at the knee

To investigate the short-term effects of recreational running on the deformation of knee articular cartilage and to examine the relationship between changes in knee cartilage volume and biomechanical modulators of knee joint load. Twenty healthy volunteers participated in a two phase cross-sectional study. Session 1 involved Magnetic Resonance Imaging (MRI) of femoral and tibial cartilage volumes prior to and following a 30 min period of relaxed sitting, which was directly followed by a recreational run of 5000 steps. Subsequently, all participants undertook a laboratory study of their running gait to compare biomechanical derived measures of knee joint loading with changes in cartilage volume. Estimates of knee joint load were determined using a rigid-link segment, dynamic biomechanical model of the lower limbs and a simplified muscle model. Running resulted in significant deformation of the medial (5.3%, P<0.01) and lateral femoral cartilage (4.0%, P<0.05) and lateral aspect of the tibial cartilage (5.7%, P<0.01), with no significant differences between genders. Maximum compression stress was significantly correlated with percentage changes in lateral femoral cartilage volume (r(2)=0.456, P<0.05). No other biomechanical variables correlated with volume changes. Limited evidence was found linking biomechanical measures of knee joint loading and observed short-term deformation of knee articular cartilage volume following running. Further enhancement of knee muscle modelling and analysis of stress distribution across cartilage are needed if we are to fully understand the contribution of biomechanical factors to knee joint loading and the pathogenesis of knee osteoarthritis (OA).