Changes In Cartilage Structure Research Articles

A novel Osteoarthritis scoring system to separate typical OA joint degeneration from non-typical lesions in male Sprague Dawley rats

ObjectiveTo develop a novel scoring system to characterize osteoarthritis-related degeneration distinct from spontaneous subchondral bone lesions observed in the tibia and femur of male Sprague Dawley rats. MethodKnee joints from male rats following 12 weeks of a diet-induced obesity model of osteoarthritis (OA) were assessed. OA histopathological changes (OAHC) were assessed in the knee joints. All scores were evaluated using a modified Mankin score and a modified Osteoarthritis Research Society International histological score. OAHC were divided into 3 categories: (I) Typical OA score evaluating the changes in cartilage structure, cellularity, proteoglycan depletion, and tidemark integrity, (II) A novel Non-typical OA score evaluating cartilage integrity, and the size of local thickening, fragmentation and degeneration along the tidemark and the size and severity of the subchondral bone lesion, and (III) Total OA score comprised of both, the Typical and the Non-typical scores. ResultsRats exposed to a high fat/high sucrose diet had higher Typical OA score compared to a control group (Chow). Non-typical and Total OA scores revealed no differences in the severity of the lesions between the HFS and the Chow group animals. All scoring systems had excellent intra- and inter-examiner reliability. ConclusionThe spontaneous bone lesions observed in male Sprague Dawley rats can obscure the effect of the diet-induced obesity if the classical scoring system is used to assess joint degeneration. The newly proposed scoring method provides a reliable method to distinguish classical OA joint degeneration from spontaneous Non-typical lesions occurring in these rats.

Effects of alendronate on cartilage lesions and micro-architecture deterioration of subchondral bone in patellofemoral osteoarthritic ovariectomized rats with patella-baja

BackgroundPatellofemoral osteoarthritis (PFJOA) is a subtype of knee OA, which is one of the main causes of anterior knee pain. The current study found an increased prevalence of OA in postmenopausal women, called postmenopausal OA. Therefore, we designed the ovariectomized rat model of patella baja-induced PFJOA. Alendronate (ALN) inhibits osteoclast-mediated bone loss, and has been reported the favorable result of a potential intervention option of OA treatment. However, the potential effects of ALN treatment on PFJOA in the ovariectomized rat model are unknown and need further investigation prior to exploration in the clinical research setting. In this study, the effects of ALN on articular cartilage degradation and subchondral bone microstructure were assessed in the ovariectomized PFJOA rat model for 10 weeks.MethodsPatella baja and estrogen withdrawal were induced by patellar ligament shortening (PLS) and bilateral ovariectmomy surgeries in 3-month-old female Sprague–Dawley rats, respectively. Rats were randomly divided into five groups (n = 8): Sham + V; OVX + V, Sham + PLS + V, OVX + PLS + V, OVX + PLS + ALN (ALN: 70 μg/kg/week). Radiography was performed to evaluate patellar height ratios, and the progression of PFJOA was assessed by macroscopic and microscopic analyses, immunohistochemistry and micro-computed tomography (micro-CT).ResultsOur results found that the patella baja model prepared by PLS can successfully cause degeneration of articular cartilage and subchondral bone, resulting in changes of PFJOA. OVX caused a decrease in estrogen levels in rats, which aggravated the joint degeneration caused by PFJOA. Early application of ALN can delay the degenerative changes of articular cartilage and subchondral bone microstructure in castrated PFJOA rat to a certain extent, improve and maintain the micrometabolism and structural changes of cartilage and subchondral bone.ConclusionThe early application of ALN can delay the destruction of articular cartilage and subchondral bone microstructure in castrated PFJOA rat to a certain extent.

Are there gender-specific differences in hip and knee cartilage composition and degeneration? A systematic literature review

The aim of the present review is to systematically analyse the current literature about gender differences in hip or knee cartilage composition and degeneration, to help explaining how and why osteoarthritis affects women more often and more severely than men. A systematic review of the literature in English was performed. Eleven studies on 1962 patients (905 females and 787 males) that reported differences on cartilage composition between males and females were included. Nine evaluated the knee, one the hip, and one both. They were heterogeneous in their methods: one conducted histological analyses, and all the others evaluated cartilage characteristics (volume, width, and composition) through magnetic resonance imaging. All authors reported gender differences in both volume and morphology of the cartilage, from infancy to menopause. In fact, a study on 92 healthy children statistically showed significant gender differences in cartilage thickness at all sites, even after adjustment for age, body, and bone size. Gender differences become more evident after menopause, when women have a lower cartilage volume and a higher cartilage loss. Men show significantly higher knee and hip cartilage volumes than women, and women carry a significantly greater risk to develop osteoarthritis. This is in part due to body and bone size, but also depends on qualitative and quantitative differences in the composition of cartilage and its degeneration rate after menopause. Structural changes in cartilage that occur between genders during ageing have significance in the development of osteoarthritis.

Insights into the Age Dependency of Compositional MR Biomarkers Quantifying the Health Status of Cartilage in Metacarpophalangeal Joints.

(1) Background: We aim to investigate age-related changes in cartilage structure and composition in the metacarpophalangeal (MCP) joints using magnetic resonance (MR) biomarkers. (2) Methods: The cartilage tissue of 90 MCP joints from 30 volunteers without any signs of destruction or inflammation was examined using T1, T2, and T1ρ compositional MR imaging techniques on a 3 Tesla clinical scanner and correlated with age. (3) Results: The T1ρ and T2 relaxation times showed a significant correlation with age (T1ρ: Kendall-τ-b = 0.3, p < 0.001; T2: Kendall-τ-b = 0.2, p = 0.01). No significant correlation was observed for T1 as a function of age (T1: Kendall-τ-b = 0.12, p = 0.13). (4) Conclusions: Our data show an increase in T1ρ and T2 relaxation times with age. We hypothesize that this increase is due to age-related changes in cartilage structure and composition. In future examinations of cartilage using compositional MRI, especially T1ρ and T2 techniques, e.g., in patients with osteoarthritis or rheumatoid arthritis, the age of the patients should be taken into account.

Imaging of Cartilage and Chondral Defects: An Overview.

A healthy articular cartilage is paramount to joint function. Cartilage defects, whether acute or chronic, are a significant source of morbidity. This review summarizes various imaging modalities used for cartilage assessment. While radiographs are insensitive, they are still widely used to indirectly assess cartilage. Ultrasound has shown promise in the detection of cartilage defects, but its efficacy is limited in many joints due to inadequate visualization. CT arthrography has the potential to assess internal derangements of joints along with cartilage, especially in patients with contraindications to MRI. MRI remains the favored imaging modality to assess cartilage. The conventional imaging techniques are able to assess cartilage abnormalities when cartilage is already damaged. The newer imaging techniques are thus targeted at detecting biochemical and structural changes in cartilage before an actual visible irreversible loss. These include, but are not limited to, T2 and T2* mapping, dGEMRI, T1ρ imaging, gagCEST imaging, sodium MRI and integrated PET with MRI. A brief discussion of the advances in the surgical management of cartilage defects and post-operative imaging assessment is also included.

Early Gβγ-GRK2 Inhibition Ameliorates Osteoarthritis Development by Simultaneous Anti-Inflammatory and Chondroprotective Effects.

The G-protein-coupled receptor kinase 2 (GRK2) is an important regulator of inflammation and pathological macrophage phenotype in a variety of diseases. We hypothesize that Gβγ-GRK2 signaling promotes the early inflammatory response and chondrocyte loss in osteoarthritis (OA). Using the destabilization of the medial meniscus (DMM) model in 12-week-old male C57BL/6 mice, we determined the role of Gβγ-GRK2 signaling in synovitis, macrophage activation, and OA development. We achieved Gβγ-GRK2 inhibition at the time of DMM by administering the Gβγ inhibitor “gallein” and the GRK2 inhibitor “paroxetine” daily, starting from 2 days before DMM surgery, for a duration of 1 or 12 weeks. Synovial and cartilage structural changes were evaluated by histomorphometry, and molecular events and macrophage activation were examined. We studied the direct role of Gβγ-GRK2 in synovitis and macrophage activation in vitro using SW982 and THP1 cells. Continuous Gβγ-GRK2 inhibition initiated at the time of DMM attenuated OA development and decreased chondrocyte loss more effectively than delayed treatment. GRK2 expression and the M1 macrophage phenotype were elevated in the inflamed synovium, while early gallein and paroxetine treatment for 1 and 12 weeks following DMM resulted in their reduction and an upregulated M2 macrophage phenotype. In vitro experiments showed that Gβγ-GRK2 inhibition attenuated synoviocyte inflammation and the M1 phenotype. We show that early Gβγ-GRK2 inhibition is of higher therapeutic efficacy in OA than delayed inhibition, as it prevents OA development by inhibiting the early inflammatory response.

Paper 84: Differences in Metrics of Knee Joint Loading Between Individuals Following a Primary Anterior Cruciate Ligament Repair (ACL-R) Surgery Versus Those Who Underwent a Standard ACL Reconstruction with a Patella Bone-Tendon-Bone Autograft (ACLR)

Objectives:Recent research suggests that the short- and long-term outcomes following Anterior Cruciate Ligament Reconstructions (ACLR) on knee joint health are worse than originally thought. The ACLR procedure may result in or expediate the arthritic process through a variety of factors including prolonged underloading of the knee joint following surgery. These recent findings have resulted in a renewed interest in the ACL repair (ACL-r) procedure as a potentially more joint “friendly” secondary to less surgical trauma with the preservation of the native ACL ligament. In several animal models and in human clinical data, ACL remnant preservation and ACL entire ligament repair/preservation has been shown to benefit lower extremity and knee biomechanics, proprioception, and short term clinical outcomes. However, there is limited data on the newer ACL-r techniques and their subsequent outcomes on knee joint loading. Therefore, the purpose of this study was to assess for differences in metrics of knee joint loading between individuals following a primary anterior cruciate ligament repair (ACL-r) surgery versus those who underwent a standard ACL reconstruction with a patella bone-tendon-bone autograft (ACLR).Methods:A total of 30 participants were enrolled into this study [ACL-r n: 15, age(yrs): 38.8±13.9, Ht(cm): 173.4±10.0, Wt(kg): 77.9±17.5; ACLR: n: 15, age(yrs): 25.60±1.7, Ht(cm): 173.5±10.3, Wt(kg): 75.4±15.6]. Participants in ACL-r group all sustained a proximal ACL disruption (Sherman Classification Type 1 or 2) that was amenable to repair and underwent primary ACL repair with suture fixation. ACL-r was performed under arthroscopic visualization with 2 or 3 standard portals in a technique similar to that described by van der list, MD (2017), but modified by the senior author to include only one 4.75mm swivelock (Arthrex) secured in the anterior aspect of the native footprint on the medial wall of the lateral femoral condyle. Participants in the ACLR group all underwent a primary ACLR with patella bone-tendon-bone autograft. The autograft bone blocks were crimped to 9mm and then two 10mm femoral and tibial tunnels created for the graft. An independent tunnel technique, utilizing the medial portal for creation of the femoral socket within the native ACL femoral attachment site, was performed in all ACLR patients. At 12 weeks following surgery participants in both groups completed the IKDC questionnaire and biomechanical testing with two AMTI force plates and a 10 camera Qualisys motion capture system. Peak knee extension moment (Nm/Ht*Wt) and total knee joint power (Watt/Ht*Wt) as a measure of eccentric loading (contraction) during the descent phase of a single-leg squat were calculated on the surgical limb and averaged across the middle three trials. Participants also completed quadriceps strength testing on both limbs (surgical and non-surgical) on an isokinetic dynamometer at 60 °/sec. The average peak torque of five repetitions were used to calculate a limb symmetry index (LSI) [Surgical/NonSurgical X100]. Independent t-tests were used to assess for differences between groups in three metrics. For descriptive purposes a separate independent t-test was used to assess for differences in age, height, mass, and IKDC scores. Statistical significance was set at P< 0.05 for all analyses.Results:There were no differences in height (p=0.996), mass(p=.678), or IKDC ( p=0.886) scores between the groups; however, there was a significant difference in age (p=0.009). The ACL-r had a significantly greater peak knee extension moment (ACL-r: -0.078±0.02; ACLR: -0.059±.02; p=0.014) and total knee joint power (ACL-r-0.03±0.01; ACLR: -0.02±0.01, p=0.016) than the ACLR group. The ACL-r also had a significantly great quadriceps LSI than the ACLR group (ACL-r: 65.09±20.4, ACLR: 49.2±11.4, p=0.014).Conclusions:The results of this study indicate that those individuals following ACL-r demonstrate increased knee joint loading during a single leg squat task compared to those who underwent ACLR. Decreases in knee extension moment have been reported across a variety of tasks and across a variety of time points following ACLR. Furthermore, decreased knee extension moments have been associated with movement profiles that have been linked to cartilage degeneration following ACLR. The improved knee extension moment in the ACL-r group at this early time may indicate a positive change in joint loading and potentially a decreased rate of cartilage degeneration. Knee joint total power accounts for both knee moment and angular velocity, indicating improved knee loading throughout the entire eccentric movement in the ACL-r group and further supports the notion of improved knee joint loading following ACL-r compared to ACLR. Decreased quadriceps muscle strength has been associated with changes in cartilage structure and it has been suggested that maximizing muscle strength in the first 6 months following surgery may promote improved cartilage healing, thus the increased quadriceps LSI in the ACL-r may be protective early in the recovery process.

Adjacent cartilage tissue structure after successful transplantation: a quantitative MRI study using T2 mapping and texture analysis

ObjectivesThe aim of this study was to assess the texture of repair tissue and tissue adjacent to the repair site after matrix-associated chondrocyte transplantation (MACT) of the knee using gray-level co-occurrence matrix (GLCM) texture analysis of T2 quantitative maps.MethodsTwenty patients derived from the MRI sub-study of multicenter, single-arm phase III study underwent examination on a 3 T MR scanner, including a T2 mapping sequence 12 and 24 months after MACT. Changes between the time points in mean T2 values and 20 GLCM features were assessed for repair tissue, adjacent tissue, and reference cartilage. Differences in T2 values and selected GLCM features between the three cartilage sites at two time points were analyzed using linear mixed-effect models.ResultsA significant decrease in T2 values after MACT, between time points, was observed only in repair cartilage (p < 0.001). Models showed significant differences in GLCM features between repair tissue and reference cartilage, namely, autocorrelation (p < 0.001), correlation (p = 0.015), homogeneity (p = 0.002), contrast (p < 0.001), and difference entropy (p = 0.047). The effect of time was significant in a majority of models with regard to GLCM features (except autocorrelation) (p ≤ 0.001). Values in repair and adjacent tissue became similar to reference tissue over time.ConclusionsGLCM is a useful add-on to T2 mapping in the evaluation of knee cartilage after MACT by increasing the sensitivity to changes in cartilage structure. The results suggest that cartilage tissue adjacent to the repair site heals along with the cartilage implant.Key Points• GLCM is a useful add-on to T2mapping in the evaluation of knee cartilage after MACT by increasing the sensitivity to changes in cartilage structure.• Repair and adjacent tissue became similar to reference tissue over time.• The results suggest that cartilage tissue adjacent to the repair site heals along with the cartilage implant.

TANTALUM OXIDE NANOPARTICLES FOR CONTRAST ENHANCED COMPUTED TOMOGRAPHY IMAGING OF CARTILAGE

Purpose: Contrast-enhanced computed tomography (CECT) allows detection of changes in cartilage structure and function via use of a contract agent, which diffuses into cartilage. The aim of this study is to investigate potential of a novel nanoparticle contrast agent for computed tomography (CT) diagnosis of osteoarthritis. An early indicator of cartilage degeneration is the loss of collagens and proteoglycans (PG) leading to enhanced tissue permeability and decreased tissue mechanical integrity.

Study on the Protective Effect and Mechanism of the Rhizoma Drynariae-Epimedium Formula on Osteoarthritis in Rats.

Purpose The aim of the study was to study the protective effect of the Rhizoma Drynariae-Epimedium formula on osteoarthritis in rats and to explore its mechanism. Methods Fifty SD rats were randomly divided into 5 groups, namely, the control group, model group, Rhizoma Drynariae group, Epimedium group, and Rhizoma Drynariae-Epimedium group, with 10 rats in each group. Knee arthritis models were established by injecting papain solution (10% papain + 0.03 mol/L L-cysteine mixture) into the knee joint cavity of SD rats on the 0th, 3rd, and 6th days of the experiment, respectively. The model group, Rhizoma Drynariae group, Epimedium group, and Rhizoma Drynariae-Epimedium group were given modeling treatment, while the control group was not given modeling treatment. The Rhizoma Drynariae group, Epimedium group, and the Rhizoma Drynariae-Epimedium group were, respectively, given corresponding solvent gavage treatment. Both the model group and the control group were given an equal volume of normal saline. Once a day, a total of 4 w were administered. The general conditions of the rats were observed and recorded, and the knee joint width and the knee joint swelling degree of the affected side were measured and compared. HE staining and Safranin O-fast green staining were used to compare the structural changes of cartilage. The concentrations of inflammatory factors IL-1β, IL-6, and TNF-α in the joint cavity lavage fluid were determined by using ELISA. The expression of key proteins of the MAPK signaling pathway (p38, p-p38, ERK, p-ERK, JNK, and p-JNK) in joint synovial tissue was determined by western blotting. Results After modeling, except for the normal activities of the SD rats in the control group, the rest of the groups showed lack of energy and a slight limp in the knee joints. The SD rats in the model group, Rhizoma Drynariae group, Epimedium group, and Rhizoma Drynariae-Epimedium group had local swelling of the knee joint, and the knee joint width was greater than those in the control group (p < 0.05). Compared with the model group, the knee joint swelling of SD rats in the Rhizoma Drynariae group, the Epimedium group, and the Rhizoma Drynariae-Epimedium group was significantly reduced. The knee joint swelling degree of SD rats in the Rhizoma Drynariae-Epimedium group was significantly lower than that in the Rhizoma Drynariae and Epimedium groups. HE staining and Safranin O-fast green staining showed that the cartilage structure of SD rats was severely damaged and eroded, and the subchondral bone mass was reduced. Compared with the model group, the damage of cartilage tissue in the Rhizoma Drynariae group, Epimedium group, and Rhizoma Drynariae-Epimedium group was less severe. In the Rhizoma Drynariae-Epimedium group, cartilage tissue structure damage and erosion were lighter than those of the Rhizoma Drynariae group and the Epimedium group. The concentrations of inflammatory factors IL-1β, IL-6, and TNF-α in the articular cavity lavage fluid of SD rats in the model group, Rhizoma Drynariae group, Epimedium group, and Rhizoma Drynariae-Epimedium group were higher than those in the control group. Compared with the model group, the concentrations of IL-1β, IL-6, and TNF-α in the joint cavity lavage fluid of the Rhizoma Drynariae group, Epimedium group, and Rhizoma Drynariae-Epimedium group were significantly decreased. In the Rhizoma Drynariae-Epimedium group, IL-1β, IL-6, and TNF-α concentrations were lower than those of the Rhizoma Drynariae and Epimedium groups. Compared with the control group, the expression levels of p-p38, p-ERK, and p-JNK proteins in the model group, Rhizoma Drynariae group, Epimedium group, and Rhizoma Drynariae-Epimedium group were significantly increased. The expression levels of p-ERK, p-p38 and p-JNK in the Drynariae group, Epimedium group, and Drynariae-Epimedium group were significantly lower than those in the model group. The expression levels of p-ERK, p-p38, and p-JNK in the Rhizoma Drynariae-Epimedium group were significantly lower than those in the Rhizoma Drynariae and Epimedium groups. Conclusion The Rhizoma Drynariae-Epimedium formula can play a protective role in the process of osteoarthritis by inhibiting the phosphorylation levels of p38, ERK, and JNK-related proteins in the cartilage tissue MAPK signaling pathway, reducing the inflammatory response.

Magnetic resonance imaging of rheumatological diseases.

Magnetic resonance imaging (MRI) is extremely useful in the early diagnosis of rheumatologic diseases, as well as in the monitoring of treatment response and disease progression to optimize long-term clinical outcomes. MRI is highly sensitive and specific in detecting the common findings in rheumatologic diseases, such as bone marrow oedema, cartilage disruption, articular erosions, joint effusions, bursal effusions, tendon sheath effusions, and synovitis. This imaging modality can demonstrate structural changes of cartilage and bone destruction years earlier than radiographs. Rheumatoid arthritis, crystal deposition diseases (including gouty arthropathy and calcium pyrophosphate deposition disease), seronegative spondyloarthropathies (including psoriatic arthritis, reactive arthritis, ankylosing spondylitis), and osteoarthritis have characteristic appearances on MRI. Contrast-enhanced MRI and diffusion-weighted imaging can provide additional evaluation of active synovitis. This article describes the MRI findings of normal joints, as well as the pathophysiological mechanisms and typical MRI findings of rheumatoid arthritis, gouty arthritis, calcium pyrophosphate deposition disease, psoriatic arthritis, reactive arthritis, ankylosing spondylitis, and osteoarthritis.

Mechanical metrics may show improved ability to predict osteoarthritis compared to T1rho mapping

Changes in cartilage structure and composition are commonly observed during the progression of osteoarthritis (OA). Importantly, quantitative magnetic resonance imaging (MRI) methods, such as T1rho relaxation imaging, can noninvasively provide in vivo metrics that reflect changes in cartilage composition and therefore have the potential for use in early OA detection. Changes in cartilage mechanical properties are also hallmarks of OA cartilage; thus, measurement of cartilage mechanical properties may also be beneficial for earlier OA detection. However, the relative predictive ability of compositional versus mechanical properties in detecting OA has yet to be determined. Therefore, we developed logistic regression models predicting OA status in an ex vivo environment using several mechanical and compositional metrics to assess which metrics most effectively predict OA status. Specifically, in this study the compositional metric analyzed was the T1rho relaxation time, while the mechanical metrics analyzed were the stiffness and recovery (defined as a measure of how quickly cartilage returns to its original shape after loading) of the cartilage. Cartilage recovery had the best predictive ability of OA status both alone and in a multivariate model including the T1rho relaxation time. These findings highlight the potential of cartilage recovery as a non-invasive marker of in vivo cartilage health and motivate future investigation of this metric clinically.

The effect of viscosupplementation on early-stage knee osteoarthritis: Clinical evaluation and assessment of cartilage in vivo with 7 T MRI

IntroductionViscosupplementation is a well-known strategy for managing early stages knee Osteoarthritis. However, despite its effectiveness in reducing symptoms, it has not yet been found to have an effect on joint cartilage. The aim of this study is to evaluate the clinical efficacy of a new product with gel-like behaviour and its in vivo effects on joint cartilage. Methods20 patients were treated by 2 consecutive injections of hyaluronan derivative Hymovis® at one-week interval. Clinical evaluation was performed before the treatment and at each time point during the follow-up using WOMAC and VAS. A 7 T magnet was used for cartilage evaluation at each MRI time point: T2 Relaxation Time (RT), T2∗ RT and cartilage parameters were evaluated before the first injection, after 45 days and at 6 months follow-up. Statistical analysis was obtained for each reported data. ResultsWe report significantly reduction in symptoms with an increase in knee and global activity functions. The T2 RT for lateral tibial compartment and T2∗ RT for Patello-Femoral compartment significantly decreased. A T2 RT reduction was observed in all knee compartments except for the medial tibial one, while a T2∗ RT reduction was observed in all knee compartments. We report an increase in cartilage volume and thickness in most of patients with a reduction of cartilage defects in 9 patients, but we didn't find MRI signals clearly referable to cartilage regeneration. ConclusionsMRI results have confirmed the possibility to employ 7T magnets to evaluate early changes in cartilage structure in vivo. HA VS has provided good clinical outcomes and an improvement in the global assessment of the knee joint, but it doesn't seem to significantly modify the cartilage over the time.

Detecting Knee Cartilage Structural Changes Using Magnetic Resonance Computed Vision Analysis in Patients with Osteoarthritis: Preliminary Results

Abstract Based on epidemiological data, osteoarthritis (OA) is the most common joint disease of populations of industrialised countries. The increasing prevalence of OA is closely related to an ageing population and a sedentary lifestyle. Load-bearing joints, such as hip, knee, and intervertebral joints, are the primary ones that are being subjected to the degenerative changes. The patho-physiology of the disease is based on progressive damage and gradual deterioration of the micro and macrostructure of hyaline cartilage. In today’s radiological practice, the first-line method for assessing the condition of articular cartilage is magnetic resonance imaging (MRI). However, the sensitivity of standard clinical MRI in articular cartilage assessment is limited. For this reason, for the last five years there has been a rapidly growing interest in developing advanced MRI techniques for cartilage structure evaluation. The purpose of this pilot study was to highlight the possibilities of Artificial Intelligence Computed Vision Analysis (MEDH 3.0 algorithm) in the evaluation of cartilage changes of the knee joint. The study was carried out at Rīga East Clinical University Hospital (RAKUS) and included 25 patients. After assessment by a rheumatologist, the participants were divided into two groups: 15 (60%) participants with OA and 10 (40%) healthy individuals. All patients underwent MRI examinations according to a unified RAKUS Gaiïezers Radiology clinic protocol. MRI data were analysed using the Computed Vision Analysis MEDH 3.0 algorithm. The results showed substantial differences in intensity variance (p &lt; 0.01) parameters, as well as in pixel entropy and homogeneity values (p &lt; 0.01). The results of the pilot study confirmed the potential use of Artificial Intelligence Computed Vision Analysis in further development and integration in the assessment of cartilage changes in the knee joint.

Impact of type III collagen on monosodium iodoacetate-induced osteoarthritis in rats

Osteoarthritis (OA) is a degenerative chronic disease that affects various tissues surrounding the joints, such as the subchondral bone and articular cartilage. The purpose of the study was to investigate the impact of collagen type III (CIII; 10 mg/kg; p.o.) on OA evidenced by restoration of articular cartilage structural changes as well as inflammatory responses using an established rat model of OA. OA was induced in rats by a single intra-articular injection of monosodium iodoacetate (MIA) through the right knee of the rats. Oral administration of CIII was undergone for 14 consecutive days. Changes in joint volume were measured throughout the experiment period with one-week intervals. At the end of the experiment, the rats were placed in the activity cage, and their activities were counted. Oxidative stress and nitrosative biomarkers were assessed by measuring the serum levels of malondialdehyde (MDA), reduced glutathione (GSH) and nitric oxide (NOx). Moreover, inflammatory markers viz. interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis nuclear factor-alpha (TNF-α) were measured. In addition, radiographic analysis and histopathological examination of the rat's knee were performed. The results of the current study revealed that oral treatment of MIA-induced osteoarthritic rats with CIII (10 mg/kg) for two weeks showed a marked decrease in the joint volume which led eventually to a prominent increase in the motor activity. Furthermore, treatment with CIII restored the serum levels of MDA, GSH, NOx, IL-6, IL-1β and the TNF-α. Furthermore, CIII succeeded to ameliorate the detrimental effect of MIA on radiographic images and histopathological alterations of the joint. From these findings, it can be concluded that CIII has regenerative and anti-inflammatory properties, thus has the ability to counteract MIA-induced OA in rat. Finally, CIII is said to be a potential anti-osteoarthritic candidate.

An inter-vendor study of scan-rescan and left-right knee asymmetry variability of cartilage T2 transverse relaxation time and morphometry assessed simultaneously using a single rapid 4-minute MRI scan

Purpose: Quantitative MRI techniques that assess changes in cartilage structure (morphometry) and composition (T2 relaxometry) have been widely applied in OA research, particularly in the Osteoarthritis Initiative (OAI). However, in the OAI, the double-echo steady-state (DESS) and the multi-echo spin-echo MRI sequences to study morphometry and T2 transverse relaxation times respectively, required 21 minutes of scan time per knee, and all scanning was performed on MRI scanners from only a single vendor.

Dexamethasone: chondroprotective corticosteroid or catabolic killer?

While glucocorticoids have been used for over 50 years to treat rheumatoid and osteoarthritis pain, the prescription of glucocorticoids remains controversial because of potentially harmful side effects at the molecular, cellular and tissue levels. One member of the glucocorticoid family, dexamethasone (DEX) has recently been demonstrated to rescue cartilage matrix loss and chondrocyte viability in animal studies and cartilage explant models of tissue injury and post-traumatic osteoarthritis, suggesting the possibility of DEX as a disease-modifying drug if used appropriately. However, the literature on the effects of DEX on cartilage reveals conflicting results on the drug’s safety, depending on the dose and duration of DEX exposure as well as the model system used. Overall, DEX has been shown to protect against arthritis-related changes in cartilage structure and function, including matrix loss, inflammation and cartilage viability. These beneficial effects are not always observed in model systems using initially healthy cartilage or isolated chondrocytes, where many studies have reported significant increases in chondrocyte apoptosis. It is crucially important to understand under what conditions DEX may be beneficial or harmful to cartilage and other joint tissues and to determine potential for safe use of this glucocorticoid in the clinic as a disease-modifying drug.

Multi-compositional MRI evaluation of repair cartilage in knee osteoarthritis with treatment of allogeneic human adipose-derived mesenchymal progenitor cells

BackgroundWe used multimodal compositional magnetic resonance imaging (MRI) techniques, combined with clinical outcomes, to differentiate the alternations of composition in repair cartilage with allogeneic human adipose-derived mesenchymal progenitor cells (haMPCs) in knee osteoarthritis (KOA) patients.MethodsEighteen patients participated a phase I/IIa clinical trial. All patients were divided randomly into three groups with intra-articular injections of haMPCs: the low-dose (1.0 × 107 cells), mid-dose (2.0 × 107), and high-dose (5.0 × 107) groups with six patients each. Compositional MRI examinations and clinical evaluations were performed at different time points.ResultsSignificant differences were observed in quantitative T1rho, T2, T2star, R2star, and ADC measurements in patients of three dose groups, suggesting a possible compositional changes of cartilage with the treatment of allogeneic haMPCs. Also significant reduction in WOMAC and SF-36 scores showed the symptoms might be alleviated to some extent with this new treatment. As regards sensibilities of multi-parametric mappings to detect compositional or structural changes of cartilage, T1rho mapping was most sensitive to differentiate difference between three dose groups.ConclusionsThese results showed that multi-compositional MRI sequences might be an effective tool to evaluate the promotion of the repair of cartilage with allogeneic haMPCs by providing information of compositional alterations of cartilage.Trial registrationClinicaltrials, NCT02641860. Registered 3 December 2015.

Age-related morphometric changes of the tidemark in the ovine stifle.

Though the ovine stifle is commonly used to study osteoarthritis, there is limited information about the age-related morphometric changes of the tidemark. The objective of this study was to document the number of tidemarks in the stifle of research sheep without clinical signs of osteoarthritis and of various ages (n=80). Articular cartilage of the medial and lateral tibial condyles and of the medial and lateral femoral condyles was assessed by histology: (a) to count the number of tidemark; and (b) to assess the OARSI (Osteoarthritis Research Society International) score for structural changes of cartilage. The number of tidemarks varied between anatomical regions, respectively, from 4.2 in the medial femoral condyle to 5.0 in the lateral tibial condyle. The axial part showed a significant higher number of tidemarks than the abaxial part, for all regions except the medial tibial condyle. Whilst the tidemark count strongly correlated with age (Spearman's correlation coefficient=0.70; 95% confidence interval (95% CI): 0.67-0.73; p<0.0001), the OARSI score was weakly correlated with age in our cohort of sheep (Spearman's correlation coefficient=0.25; 95% CI: 0.19-0.30; p<0.0001). Interestingly, no tidemark was seen in the three animals aged 6months. Our data indicate that the number of tidemarks increases with age and vary with anatomical region. The regional variation also revealed a higher number of tidemarks in the tibia than in the femur. This could be attributed to the local variation in cartilage response to strain and to the difference in chondrocyte biology and density.

Detection of osteoarthritis using acoustic emission analysis

Osteoarthritis (OA) of the knee is a widespread disease, often resulting in pain, restricted mobility and a reduction of activities and participation. Initial studies gave hints that Acoustic Emission Analysis (AEA) is capable of detecting early changes in cartilage structure. However, up to date no in vivo validation studies have been conducted. A prospective pilot study was conducted to investigate this diagnostic capability and the accuracy of the AEA, using magnetic resonance imaging (MRI) as a reference standard. Additionally, potential factors influencing false positive or negative results were studied.Twenty-eight patients, receiving MRI due to discomfort of the knee, were examined with AEA.Sensitivity was 0.92 for the whole knee and 0.86 to 1 for different parts of the knee. The specificity was 0.7 and 0.59 to 0.78, respectively. Confidence intervals varied between 0 and 0.33 for sensitivity and 0.1 and 0.24 for specificity.The diagnostic accuracy of the AEA was shown to be good to very good. However, because of the relatively small number of patients involved, interpretation of the data should be handled with care. Future studies with greater sample sizes have to be conducted to confirm the results of this investigation.