Meniscal Score Research Articles

Bone Marrow–Derived Fibrin Clots Stimulate Healing of a Knee Meniscal Defect in a Rabbit Model

To determine the invivo effectiveness of bone marrow aspirate-derived (BMA) fibrin clots for avascular meniscal defect healing in a rabbit model. In 42 Japanese white rabbits, a 2.0-mm cylindrical defect was introduced into the avascular zone of the anterior part of the medial meniscus in the bilateral knees. The rabbits were grouped according to implantation of a BMA fibrin clot (BMA group) or a peripheral blood (PB)-derived clot (PB group) into the defect and nonimplantation (control group). Macroscopic and histological assessments were performed using a scoring system at 4 and 12 weeks after surgery. At 12 weeks after surgery, compressive stress was analyzed biomechanically. The meniscal score in the BMA group (12.1) was greater than that in the PB group (5.5; P= .031) and control group (4.4; P= .013) at 4 weeks. The meniscal score in the BMA group (13.1) was greater than that in the control group (6.4; BMA= 13.1; P= .0046) at 12 weeks. In the biomechanical analysis, the BMA group demonstrated significantly higher compressive strength than the PB group (6.6 MPa) (BMA= 15.4 MPa; P= .0201) and control group (3.6 MPa; BMA= 15.4 MPa; P= .007). Implantation of BMA fibrin clots into the meniscal defect of the avascular zone in a rabbit model improved the meniscal score at 4 weeks and strengthened the reparative meniscal tissue at 12 weeks compared with the implantation of PB fibrin clots. Healing in the avascular zone of the meniscus can be problematic. Approaches to improving this healing response have had variable results. This study provides additional information that may help improve the outcomes in patients with these injuries.

Development and characterization of a humanized mouse model of osteoarthritis

In light of the role of immune cells in OA pathogenesis, the development of sophisticated animal models closely mimicking the immune dysregulation during the disease development and progression could be instrumental for the preclinical evaluation of novel treatments. Among these models, immunologically humanized mice may represent a relevant system, particularly for testing immune-interacting DMOADs or cell therapies before their transfer to the clinic. Our objective, therefore, was to develop an experimental model of OA by destabilization of the medial meniscus (DMM) in humanized mice. Irradiated 5-week-old NOD/LtSz-scid IL2Rγnull (NSG) mice were humanized by intravenous injection of CD34+ human hematopoietic stem cells. The engraftment efficiency was evaluated by flow cytometry 17 weeks after the humanization procedure. Humanized and non-humanized NSG mice underwent DMM or sham surgery and OA development was assessed 1, 6, and 12 weeks after the surgery. 120 days after the humanization, human T and B lymphocytes, macrophages and NK cells, were present in the blood and spleen of the humanized NSG mice. The DMM surgery induced articular cartilage and meniscal alterations associated with an increase in OA and the meniscal score. Moreover, the surgery triggered an inflammatory response that was sustained at a low grade in the DMM group. Our study shows for the first time the feasibility of inducing OA by DMM in humanized mice. This novel OA model could constitute a useful tool to bridge the gap between the preclinical and clinical evaluation of immune interacting DMOADs and cell-based therapies.

Joint-adjacent Adipose Tissue by MRI is Associated With Prevalence and Progression of Knee Degenerative Changes: Data from the Osteoarthritis Initiative.

Adipose tissue has recently gained interest as an independent imaging biomarker for osteoarthritis. To explore 1) cross-sectional associations between local subcutaneous fat (SCF) thickness at the knee and the extent of degenerative changes in overweight and obese individuals and 2) associations between local fat distribution and progression of osteoarthritis over 4 years. Retrospective cohort study. 338 obese and overweight participants from the Osteoarthritis Initiative cohort without radiographic evidence of osteoarthritis. 3T: 3D-FLASH-WE; 3D-DESS-WE; T1w-SE; MSME. Baseline SCF thickness was measured in standardized locations medial, lateral and anterior to the knee and the average joint-adjacent SCF (ajSCF) was calculated. Right thigh SCF cross-sectional area was assessed. Quantitative cartilage T2 relaxation times and semi-quantitative whole organ MRI scores (WORMS) were obtained at baseline and 4-year follow-up. WORMSsum was calculated as sum of cartilage, bone marrow edema, subchondral cyst, and meniscal scores. Associations of SCF measures with baseline, and 4-year change in T2 and WORMS were analyzed using regression models. SCF measurements were standardized using the equation . Analyses were adjusted for age, sex, physical activity, and BMI. Cross-sectionally, significant associations between lateral SCF, lateral compartment WORMS and T2 were found ( , [95% CI]: 0.53, [0.12-0.95], P < 0.05; ΔT2 : 0.50, [0.02-0.98], P < 0.05). Moreover, greater lateral SCF was associated with faster progression of lateral WORMSsum gradings (OR=1.50, [1.05-2.15], P < 0.05). No significant positive associations were found for thigh SCF and WORMSsum (P=0.44) or T2 measurements (medial: P=0.15, lateral: 0.39, patellar: P=0.75). Joint-adjacent SCF thickness was associated with imaging parameters of knee osteoarthritis, both cross-sectionally and longitudinally, while thigh SCF was not, suggesting a spatial association of SCF and knee osteoarthritis. Based on these findings, joint-adjacent SCF may play a role in the development and progression of knee osteoarthritis. 4 TECHNICAL EFFICACY: Stage 5.

Flexion contracture is associated with knee joint degeneration on magnetic resonance imaging: data from the Osteoarthritis Initiative.

Knee osteoarthritis (OA) is often accompanied by a flexion contracture (FC), resulting in worse clinical outcomes. Our objective was to determine associations between knee FC and specific regional and/or structural alterations on magnetic resonance imaging (MRI) using the Osteoarthritis Initiative (OAI). 600 knees from the Foundation for the National Institutes of Health sub-study of the OAI were included. Knee extension was measured with a goniometer and FC was defined as inability to extend the knee to 0°. Structural alterations within the MRI Osteoarthritis Knee Score (MOAKS)-assessed regions that could potentially obstruct knee extension were primarily analysed. Multivariable linear regression models evaluated the effect size of MRI outcomes on knee extension. One-third (33.4%) of all participants had knee FC: 155 mild (1-5°, 26.0%), 44 moderate-severe (≥6°, 7.4%). Mean knee alignment was 0.3±3.7° valgus. Cartilage morphology and bone marrow lesion (BML) scores on the femoral side of the lateral patellofemoral joint were associated with lost knee extension (β=0.709, p<0.001, and β=0.666, p<0.001, respectively) as were higher osteophyte scores in multiple regions, worse meniscal score in the medial meniscal body (β=0.164, p<0.040) and posterior horn (β=0.400, p<0.001), and a worse effusion score (β=0.711, p<0.001). Knee flexion contractures were associated with non-specific, widespread MRI degenerative changes including cartilage loss and BMLs in the lateral patellofemoral joint, osteophytes, meniscal alterations and whole-joint effusion. Loss of knee extension in OA is likely a structurally-multifactorial outcome.

MR variability of collagen meniscal implant remodelling in patients with good clinical outcome.

Collagen meniscal implants (CMI) have variable imaging findings on MRI and it remains ambiguous, if alterations may be present in asymptomatic patients. The aim was, to evaluate MR morphological characteristics and volume of CMI in the early, mid- and long-term follow-up. Fifty-seven patients (mean age, 43.6±11years; 41 male/16 female) with good clinical outcome (subjective visual analogue scale for satisfaction < 2 and a Lysholm-score ≥ 84) after CMI were assessed retrospectively using MRI 1, 2 and 3-8years postoperatively. CMI morphology, signal intensity (SI), homogeneity and size were assessed and a meniscal score was calculated. Chondral defects and bone marrow edema pattern were reported and summarized in a chondral score. Meniscal extrusion and volume were evaluated. Intra- and inter-reader reliabilities were calculated. Spearman and partial correlations were used (p < 0.05). One year postoperatively, the CMI varied in size [10% (4/40) normal, 30% (12/40) small, 60% (24/40) hypertrophic] and was hyperintense and inhomogeneous in all patients. At long-term follow-up, the size of CMI decreased [6% (1/17) resorbed, 18% (3/17) normal, 41% (7/17) small, 35% (6/17) hypertrophic]. The SI of the CMI changed to normal in only 13% (2/16). The majority was still hyperintense [87% (14/16)]. Less meniscal extrusion was present in the follow-up [71% (11/16) versus initially 93% (37/40)]. The meniscal score improved significantly (ρ = 0.28). Over time, full-thickness femoral chondral defects were increasingly present [65% (10/17) versus initially 33% (13/40)] and the chondral score worsened significantly (p = 0.017). Abnormal and inhomogeneous SI and irregular margins of the early postoperative CMI on MRI are findings seen in patients with good clinical results and should not necessarily be overcalled when reporting MRI. These features tend to decrease over time. IV.

Association between objectively assessed physical activity measures and longitudinal knee structural damage

Purpose: The relation between physical activity (PA) and the development of knee osteoarthritis (OA) is an important clinical and public health issue. Studies conducted thus far have shown conflicting results. This is most likely due to the small study samples, semi-quantitative assessment of PA and a lack of objective longitudinal data including intensity of PA. The purpose of the study was to describe the predictors and the longitudinal association between PA level and global knee structural progression. Methods: 864 participants [mean age = 65 (48–84), female % = 58] were included in this study who had valid PA data and right knee MRI data from 48 month and 72 month visits of the Osteoarthritis Initiative (OAI) study. Physical activity was monitored using ActiGraph GT1M uniaxial accelerometers (ActiGraph; Pensacola, FL). PA was categorized into time spent doing light, moderate, moderate to vigorous (MVPA) and vigorous activity depending on the activity counts/minute as described on the OAI website. PA intensity was further categorized into bouts of MVPA and vigorous activity as already describe don the OAI website. PA was further categorized to assess whether the participants met the weekly PA level prescribed American College of Sports Medicine (ACSM) and Department of Health and Human Services (DHHS). MRI data was scored using the modified Whole Organ MRI Score (WORMS). All multivariable analyses were adjusted for age, sex, BMI, radiographic OA and history of knee injury/surgery. Results: 1. Change in total modified WORMS – Baseline predictors Higher number of minutes spent doing light activity independently predicted significant worsening of total modified WORMS (β (per activity count) = +0.99 (+0.51, +1.48)). On the other hand higher number of minutes spent doing vigorous activity (β = −0.17 (−0.33, −0.01)) and more intense (β (per activity bout) = −0.14 (−0.26, −0.01)) PA were associated with a decrease in severity of WORMS over two years. – Longitudinal associations Neither changes in minutes spent in any of the four PA categories nor changes in intensity of PA over two years were significantly associated with total modified WORMS. 2. Changes in individual knee structures on MRI (i) Cartilage defects: – Baseline predictors More minutes spent doing light and moderate PA at baseline were independently associated with a significant worsening of cartilage defects over two years. – Longitudinal associations Increase in the number of minutes spent doing light activity over two years was associated with worsening cartilage defects, however increase in the minutes spent doing vigorous PA was associated with improvement in cartilage defects score. (ii) Bone marrow edema (BME): – Baseline predictors None of the baseline PA categories independently predicted change in BME over 2 years – Longitudinal associations Increase in minutes spent doing light activity was independently associated (β = 3.78 (1.42, 6.19)) with worsening BME over two years, however increase in vigorous activity minutes and intensity was associated with significant improvement in BME lesions. (iii) Meniscal pathologies – Baseline predictors More minutes spent doing light activity were associated with worsening meniscal tears over two whereas vigorous activity and higher intensity were associated with improvement in meniscal score. – Longitudinal associations Increase in time spent doing light to moderate activities was associated with improvement in meniscal scores but remained stable with vigorous PA (iv) Effusion – Baseline predictors Light activity at baseline was associated with significant improvement in severity of effusion whereas vigorous and more intense PA independently predicted worsening effusion grade. Longitudinal associations Increasing time spent doing more vigorous PA was associated with progressively worsening knee effusion. A similar trend was observed with increasing intensity of PA. Increase in PA level from baseline to meet ACSM and DHHS guidelines was generally associated with improvement in knee structural pathology grades. Conclusions: Increases in time spent doing vigorous activity and increase in intensity of PA is generally associated with a protective effect on the knee joint except for knee joint effusion that worsened with increasing level of PA.

Is arthroscopic videotape a reliable tool for describing early joint tissue pathology of the knee?

BackgroundThe aim of this study was to assess the reliability of the videotape scoring system collected during knee arthroscopy for meniscal tears, and to test the consistency with intra-operative findings. MethodsFifty-seven patients undergoing arthroscopic treatment of meniscal tears were included in the analysis. The cartilage damage was assessed intra-operatively, at six sites, using the Outerbridge scoring system. The meniscal tears were graded according to the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) classification. The presence of synovial inflammation was scored, at four different sites, according to the macro-score method. The total cartilage, meniscal and synovial scores were calculated for each knee by the sum of the maximum grade of the lesions at each anatomic site. In order to assess the reliability of the arthroscopic scoring system, the videotapes recorded during the arthroscopy were reviewed by two independent observers one year after the surgery and compared with the scores completed by the surgeon during the operation. ResultsThe total cartilage score showed substantial inter-rater and intra-rater reliability, and moderate consistency with the intra-operative score provided by the surgeon. The total meniscal score showed substantial inter-rater and intra-rater reliability, and good consistency with the intra-operative findings. The total synovial score showed substantial inter-rater agreement, substantial intra-rater reliability, and moderate consistency with intra-operative findings. ConclusionsThe videotape scoring system provided a reliable and reproducible system for recording the intra-operative state of the whole joint pathology in patients undergoing arthroscopic treatment of meniscal tears.

Semi-quantitative MRI biomarkers of knee osteoarthritis progression in the FNIH biomarkers consortium cohort - Methodologic aspects and definition of change.

BackgroundTo describe the scoring methodology and MRI assessments used to evaluate the cross-sectional features observed in cases and controls, to define change over time for different MRI features, and to report the extent of changes over a 24-month period in the Foundation for National Institutes of Health Osteoarthritis Biomarkers Consortium study nested within the larger Osteoarthritis Initiative (OAI) Study.MethodsWe conducted a nested case–control study. Cases (n = 406) were knees having both radiographic and pain progression. Controls (n = 194) were knee osteoarthritis subjects who did not meet the case definition. Groups were matched for Kellgren-Lawrence grade and body mass index. MRIs were acquired using 3 T MRI systems and assessed using the semi-quantitative MOAKS system. MRIs were read at baseline and 24 months for cartilage damage, bone marrow lesions (BML), osteophytes, meniscal damage and extrusion, and Hoffa- and effusion-synovitis. We provide the definition and distribution of change in these biomarkers over time.ResultsSeventy-three percent of the cases had subregions with BML worsening (vs. 66 % in controls) (p = 0.102). Little change in osteophytes was seen over 24 months. Twenty-eight percent of cases and 10 % of controls had worsening in meniscal scores in at least one subregion (p < 0.001). Seventy-three percent of cases and 53 % of controls had at least one area with worsening in cartilage surface area (p < 0.001). More cases experienced worsening in Hoffa- and effusion synovitis than controls (17 % vs. 6 % (p < 0.001); 41 % vs. 18 % (p < 0.001), respectively).ConclusionsA wide range of MRI-detected structural pathologies was present in the FNIH cohort. More severe changes, especially for BMLs, cartilage and meniscal damage, were detected primarily among the case group suggesting that early changes in multiple structural domains are associated with radiographic worsening and symptomatic progression.

Correlations of Medial Joint Space Width on Fixed‐Flexed Standing Computed Tomography and Radiographs With Cartilage and Meniscal Morphology on Magnetic Resonance Imaging

To assess whether medial tibiofemoral joint space width (JSW) on 3-dimensional (3-D) standing computed tomography (SCT) correlates more closely with magnetic resonance imaging cartilage morphology (CM) and meniscal scores than does radiographic 2-D JSW. Participants in the Multicenter Osteoarthritis Study, who had standing fixed-flexion posteroanterior knee radiographs, were recruited. Medial tibiofemoral 3-D JSW on SCT and 2-D JSW on fixed-flexion radiographs were compared with medial tibiofemoral cartilage and meniscal morphology using the Whole-Organ Magnetic Resonance Imaging Score (WORMS). Associations between the area of the articular surface with 3-D JSW <2.5 mm on SCT, radiographic minimal 2-D JSW, and the WORMS-CM and meniscal scores were assessed using Spearman's rho. For the 19 participants included (33 knees), mean ± SD age was 66.9 ± 5.4 years, body mass index was 29.5 ± 4.4 kg/m(2) , 42.1% of participants were female, and the Kellgren/Lawrence grades were 0 (21.2%), 1 (36.4%), 2 (18.2%), and 3 (24.2%). The articular surface area with 3-D JSW <2.5 mm on SCT correlated with WORMS-CM scores for the central medial tibia (rs = 0.84, P < 0.001), central medial femur (rs = 0.60, P < 0.007), and posterior medial meniscal tear (rs = 0.39, P < 0.026), as did other cut points for 3-D JSW. Correlations with radiographic minimal 2-D JSW were -0.66, -0.52, and -0.40, respectively, differing from SCT only for tibial cartilage (P = 0.001). Greater surface area with a low JSW, measured by SCT, correlates more strongly with the severity of tibial cartilage lesions, while correlating with medial femoral cartilage and meniscal damage to a similar extent as radiographic minimal JSW. SCT may enable valid stratification of participants in clinical trials, through quickly and inexpensively characterizing osteoarthritis features.

Comparison of BLOKS and WORMS scoring systems part II. Longitudinal assessment of knee MRIs for osteoarthritis and suggested approach based on their performance: data from the Osteoarthritis Initiative

There are two widely used scoring systems for knee magnetic resonance imaging (MRI) in osteoarthritis (OA) and the strengths and weaknesses of each system in terms of ease of use and association with known risk factors and outcomes are unknown. To compare Whole Organ Magnetic Resonance Imaging Score (WORMS) and Boston Leeds Osteoarthritis Knee Score (BLOKS) scales using longitudinal MRI and X-ray data. In the Osteoarthritis Initiative (OAI), knee radiographs, long limb films for alignment and MRI's were acquired in the interval from 0 to 24 months follow-up. OAI MRI's from baseline and 24 months were read separately using BLOKS and WORMS scales. X-rays were scored semiquantitatively for joint space loss and long limb films were measured for alignment angle. We evaluated which of the WORMS or BLOKS cartilage loss scores best correlated with joint space loss on the X-ray and which was best predicted by varus malalignment on long limb film. To examine the validity of bone marrow lesion (BML) and meniscal scales, we tested which of WORMS or BLOKS baseline scores for BML or meniscus best predicted cartilage loss from baseline to 24 months. We critically evaluated strengths and weaknesses of each scoring system also. Of 113 knees read longitudinally, 33 showed any cartilage loss using BLOKS and 30 using WORMS with high agreement between the scales. In the medial compartment, both BLOKS and WORMS picked up only 42% of the knees with X-ray joint space loss with similar specificity (88 vs 86%). Varus knees were more likely to be a risk factor for medial cartilage loss in BLOKS [adj odds ratio (OR) 5.9 (95% confidence intervals (CIs) 1.5, 24.0)] than in WORMS [adj OR 2.1 (95% CI 0.7, 6.3)]. WORMS BML scores predicted cartilage loss more strongly than any BLOKS BML variables and some BLOKS BML measures did not affect risk of cartilage loss at all. However, across the range of scores, meniscal tear scores in BLOKS predicted cartilage loss better for each abnormality than did WORMS meniscal tear scores and the meniscal signal abnormality scored in BLOKS but not in WORMS, predicted cartilage loss. BLOKS took longer and was more difficult to score longitudinally especially for BML scores. In a comparison of instruments limited by small numbers of knees compared, BLOKS meniscal score was preferable to WORMS meniscal scale in predicting cartilage loss most likely because it includes potentially important pathology missed by WORMS. On the other hand, BML scoring in WORMS was preferable in that it better predicted later cartilage loss, was easier to score and did not include potentially extraneous measures. Neither method was definitively better for cartilage scoring.

Knee joint ultrasonography of the ACLT rabbit experimental model of osteoarthritis: relevance and effectiveness in detecting meniscal lesions

To develop a protocol for rabbit knee joint ultrasonography (US); to grade ultrasonographically the meniscal injuries of the anterior cruciate ligament transection (ACLT) rabbit model of osteoarthritis (OA); to assess with US the effectiveness of the ACLT; to compare final US with macroscopy for the evaluation of medial and lateral meniscal injuries depending on the age and weight when ACLT is performed. Twenty-two skeletally mature and adolescent New Zealand white rabbits were housed during the same period at the Institut Claude-Bourgelat, Lyon, France. Surgical ACLT was performed in the left knee of nine adolescent and five adult rabbits. Final US and macroscopic semi-quantitative grading of the meniscal injuries were compared 5 months after ACLT. A standardised protocol was developed to evaluate the rabbit knee joint. US was performed in both control and ACLT knees. Normal and abnormal meniscal US appearances were described. A semi-quantitative scale to grade US meniscal injuries was created. Macroscopic and US total meniscal scores were significantly positively correlated (P<0.001, r=0.70). US detection of meniscal injuries was 92% sensitive and 87.5% specific compared to macroscopy. Positive and negative predictive values of US were, respectively, 92% and 87.5%. US detection of the ACLT effectiveness was 100% specific and 78.5% sensitive. A significant relationship was found between ultrasonographic and macroscopic grading of meniscal injuries. US was both specific and sensitive in detecting meniscal lesions. We propose US as a non-invasive, non-expensive, in vivo imaging technique for preclinical studies in the ACLT rabbit OA model.