Cartilage Thickness Research Articles

Serum ARGS-aggrecan in a phase 2 clinical trial targeting osteoarthritis

OBJECTIVETo monitor serum concentrations of the aggrecan ARGS neoepitope in a clinical trial of ADAMTS-5 inhibition as disease-modifying therapy of knee osteoarthritis, and to investigate relationships between reduction in ARGS and change in cartilage thickness, knee related pain and function. DESIGNROCCELLA trial participants received once-daily oral S201086 75, 150 or 300 mg, or placebo, for 52 weeks. Serum was collected at baseline, 4, 12, 28 and 52 weeks, and 2 weeks post treatment with ARGS measured by an in-house immunoassay. Change from baseline to week 52 in central medial femorotibial compartment cartilage thickness was measured by MRI, function and pain by WOMAC subscores. Associations between cumulative change in ARGS and change in cartilage thickness or WOMAC subscores were evaluated by linear regression. RESULTSS201086 reduced serum levels of ARGS in a dose-dependent manner throughout the treatment period. Maximal reduction was at 4 weeks with a 58.5% [95% CI 60.8%, 56.2%] reduction of ARGS compared to baseline for 300 mg S201086. Two weeks post treatment, ARGS concentrations rebounded with a dose-dependent overshoot compared to baseline levels. Cumulative change of ARGS concentration from baseline to week 52 had no effect on change in cartilage thickness (slope -0.8x10-6 [-2.9x10-6, 1.3x10-6]) or change in WOMAC pain and function (slopes -30x10-6 [-64x10-6, 5.2x10-6] and -97x10-6 [-214x10-6, 20x10-6], respectively) at week 52. CONCLUSIONSystemic inhibition of ADAMTS-5 resulted in markedly reduced serum ARGS, but change in serum ARGS concentrations showed no association with the progression of cartilage thinning, or patient reported pain and function. ClinicalTrials.govNCT03595618.

Relationships Between Running Biomechanics and Femoral Articular Cartilage Thickness and Composition in Anterior Cruciate Ligament Reconstruction Patients.

Although individuals with anterior cruciate ligament reconstruction (ACLR) are at high risk for posttraumatic osteoarthritis, mechanisms underlying the relationship between running and knee cartilage health remain unclear. We aimed to investigate how 30 min of running influences femoral cartilage thickness and composition and their relationships with running biomechanics in patients with ACLR and controls. Twenty patients with ACLR (time post-ACLR: 14.6 ± 6.1 months) and 20 matched controls participated in the study. A running session required both groups to run for 30 min at a self-selected speed. Before and after running, we measured femoral cartilage thickness via ultrasound imaging. A MRI session consisted of T2 mapping. The ACLR group showed longer T2 relaxation times in the medial femoral condyle at resting compared with the control group (central: 51.2 ± 16.6 vs. 34.9 ± 13.2 ms, p = 0.006; posterior: 50.2 ± 10.1 vs. 39.8 ± 7.4 ms, p = 0.006). Following the run, the ACLR group showed greater deformation in the medial femoral cartilage than the control group (0.03 ± 0.01 vs. 0.01 ± 0.01 cm, p = 0.001). Additionally, the ACLR group showed significant negative correlations between resting T2 relaxation time in the medial femoral condyle and vertical impulse (standardized regression coefficients = -0.99 and p = 0.004) during running. Our findings suggest that those who are between 6 and 24 months post-ACLR have degraded cartilage composition and their cartilage deforms more due to running vGRF.

Differences in ankle and knee muscle architecture and plantar pressure distribution among women with knee osteoarthritis.

The aim of this study was to compare the plantar pressure distribution and knee and ankle muscle architecture in women with and without knee osteoarthritis (OA). Fifty women with knee OA (mean age=52.11±4.96years, mean Body mass index (BMI)=30.94±4.23kg/m2) and 50 healthy women as a control group (mean age=50.93±3.78years, mean BMI=29.06±4.82kg/m2) were included in the study. Ultrasonography was used to evaluate knee and ankle muscles architecture and femoral cartilage thickness. The plantar pressure distribution was evaluated using the Digital Biometry Scanning System and Milleri software (DIASU, Italy). Static foot posture was evaluated using the Foot Posture Index (FPI), and pain severity was assessed using the Visual Analog Scale. The OA group exhibited lower muscle thickness in Rectus Femoris (RF) (p=0.003), Vastus Medialis (VM) (p=0.004), Vastus Lateralis (p=0.023), and Peroneus Longus (p=0.002), as well as lower Medial Gastrocnemius pennation angle (p=0.049) and higher Fat thickness (FT) in RF (p=0.033) and VM (p=0.037) compared to the control group. The OA group showed thinner femoral cartilage thickness (p=0.001) and higher pain severity (p=0.001) than the control groups. FPI scores were higher (p=0.001) in OA group compared to the control group. The plantar pressure distribution results indicated an increase in total surface (p=0.027), total load (p=0.002), medial load (p=0.005), and lateral load (p=0.002) on dominant side in OA group compared to the control group. Knee and ankle muscle architecture, knee extensor muscle FT, and plantar pressure distribution in the dominant foot differed in individuals with knee OA compared to the control group.

Variations in knee cartilage thickness: Fully automatic three-dimensional analysis of MRIs from five manufacturers

BackgroundMeasurements of knee cartilage thickness derived from MR images are attractive biomarkers for osteoarthritis research. Although some cross-sectional multivendor studies exist, none have employed fully automatic three-dimensional MRI analysis. Our objective was to evaluate the variations in knee cartilage thickness measurements obtained using automated methods and MRI instruments from five different vendors. MethodsThe subjects were 10 healthy volunteers aged 22–60 years. MRI models with 3 Tesla strength from five different companies were used. Cartilage thickness was quantified fully automatically for seven regions. We hypothesized that “the MRI model influences cartilage thickness measurements.” Inter-measurement error, defined as the absolute difference between the targeted and median thicknesses determined by the five MRI models, was analyzed using histograms. The factors generating the largest inter-measurement error were also examined. ResultsNo exceptional trends attributable to a specific instrument model were observed, and the p-value from the Kruskal–Wallis test exceeded 0.05 in all seven regions. Therefore, the study hypothesis was rejected. Of the 350 measurements, the inter-measurement error was ≤0.05 mm in 53 %, ≤0.10 mm in 75 %, and ≤0.20 mm in 95 %. Analysis of the medial tibial cartilage, which had the largest inter-measurement error, revealed mis-extraction of synovial fluid as cartilage. ConclusionsThe choice of MRI model did not influence cartilage thickness measurements. Overall, 95 % of the inter-measurement errors were within 0.20 mm. The greatest error resulted from mis-extracting synovial fluid as cartilage.

Interactions of cumulative load with biomarkers of cartilage turnover predict knee cartilage change over 2 years: data from the osteoarthritis initiative.

The purpose was to investigate relationships of cumulative load and cartilage turnover biomarkers with 2-year changes in cartilage in knee osteoarthritis. From participants with Kellgren-Lawrence (KL) grades of 1 to 3, cartilage thickness and transverse relaxation time (T2) were computed from 24-month (baseline) and 48-month magnetic resonance images. Cumulative load was the interaction term of the Physical Activity Scale for the Elderly (PASE) and body mass index (BMI). Serum cartilage oligomeric matrix protein (COMP) and the nitrated form of type II collagen (Coll2-1 NO2) were collected at baseline. Multiple regressions (adjusted for baseline age, KL grade, cartilage measures, pain, comorbidity) evaluated the relationships of cumulative load and biomarkers with 2-year changes. In 406 participants (63.7 (8.7) years), interactions of biomarkers with cumulative load weakly predicted 2-year cartilage changes: (i) COMP × cumulative load explained medial tibia thickness change (R2 increased 0.062 to 0.087, p < 0.001); (ii) Coll2-1 NO2 × cumulative load explained central medial femoral T2 change (R2 increased 0.177 to 0.210, p < 0.001); and (iii) Coll2-1 NO2 × cumulative load explained lateral tibia T2 change (R2 increased 0.166 to 0.188, p < 0.001). Moderate COMP or Coll2-1 NO2 at baseline appeared protective. High COMP or Coll2-1 NO2, particularly with high BMI and low PASE, associated with worsening cartilage. Moderate serum concentrations of cartilage turnover biomarkers, at high and low physical activity, associated with maintained cartilage outcomes over 2 years. In conclusion, high concentrations of cartilage turnover biomarkers, particularly with high BMI and low physical activity, associated with knee cartilage thinning and increasing T2 over 2 years. Key Points • Higher quality cartilage may be better able to tolerate a larger cumulative load than poor quality cartilage. • Among participants enrolled in the Osteoarthritis Initiative Biomarkers Consortium Project, a representation of cumulative load exposure and its interaction with cartilage turnover biomarkers were weakly related with 2-year change in knee cartilage. • These findings suggest that cartilage turnover is a factor that modifies the relationship between loading exposure and cartilage loss in knee OA.

Acromegaly in humans and cats: Pathophysiological, clinical and management resemblances and differences

ObjectiveAcromegaly is a disorder associated with excessive levels of growth hormone (GH) and insulin-like growth factor-1 (IGF-1). In general, GH/IGF-1 excess leads to morphologic craniofacial and acral changes as well as cardiometabolic complications, but the phenotypic changes and clinical presentation of acromegaly differ across species. Here, we review the pathophysiology, clinical presentation and management of acromegaly in humans and cats, and we provide a systematic comparison between this disease across these different species. DesignA comprehensive literature review of pathophysiology, clinical features, diagnosis and management of acromegaly in humans and in cats was performed. ResultsAcromegaly is associated with prominent craniofacial changes in both species: frontal bossing, enlarged nose, ears and lips, and protuberant cheekbones are typically encountered in humans, whereas increased width of the head and skull enlargement are commonly found in cats. Malocclusion, prognathism, dental diastema and upper airway obstruction by soft tissue enlargement are reported in both species, as well as continuous growth and widening of extremities resulting in osteoarticular compromise. Increase of articular joint cartilage thickness, vertebral fractures and spine malalignment is more evident in humans, while arthropathy and spondylosis deformans may also occur in cats. Generalized organomegaly is equally observed in both species. Other similarities between humans and cats with acromegaly include heart failure, ventricular hypertrophy, diabetes mellitus, and an overall increased cardiometabolic risk. In GH-secreting pituitary tumours, local compressive effects and behavioral changes are mostly observed in humans, but also present in cats. Cutis verticis gyrata and skin tags are exclusively found in humans, while palmigrade/plantigrade stance may occur in some acromegalic cats.Serum IGF-1 is used for acromegaly diagnosis in both species, but an oral glucose tolerance test with GH measurement is only useful in humans, as glucose load does not inhibit GH secretion in cats. Imaging studies are regularly performed in both species after biochemical diagnosis of acromegaly. Hypophysectomy is the first line treatment for humans and cats, although not always available in veterinary medicine. ConclusionAcromegaly in humans and cats has substantial similarities, as a result of common pathophysiological mechanisms, however species-specific features may be found.

Effects of Platelet-Rich Plasma Combined with Physical Therapy on IL-1β, TGF-β1, and MMP-3 in Patients with Knee Osteoarthritis.

The occurrence of osteoarthritis in the knee joint is regulated by a complex network, and there is currently no specific therapeutic drug available. Functional exercises and treatments targeting inflammatory factors have shown the potential to alleviate knee osteoarthritis to some extent. Therefore, the aim of this study was to assess the intra-articular injection (IAI) of autologous platelet-rich plasma (PRP) combined with physical therapy (PT) in treating knee osteoarthritis. A total of 128 patients with knee osteoarthritis were included in the study, including 64 males and 64 females. A total of 128 patients were divided into sodium hyaluronate group (HA group), PRP group, PRP + PT group, and PT group, with 32 cases in each group. Visual analog scale (VAS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and Japanese Orthopaedic Association (JOA) were employed to evaluate the recovery of patients from pain and osteoarthritis. Color Doppler ultrasound imaging technology was utilized to assess joint effusion, synovial membrane thickness, and articular cartilage thickness in patients with knee osteoarthritis. Enzyme-linked immunosorbent assay (ELISA) was employed to detect the levels of interleukin-1β (IL-1β), transforming growth factor-β1 (TGF-β1), and matrix metallopeptidase 3 (MMP-3) in the synovial fluid. Compared to the HA group, the PT group, PRP group, and PRP combined with PT (PRP + PT) group all showed reduced VAS and WOMAC scores, increased JOA scores, decreased joint effusion, synovial membrane thickness, and articular cartilage thickness in the knee joint. Additionally, levels of IL-1β and MMP-3 in the synovial fluid decreased, while TGF-β1 levels increased (P < 0.05). Compared with the PT group, the VAS and WOMAC scores of the knee joint in the PRP group decreased, JOA scores increased, joint effusion, synovial thickness, and articular cartilage thickness decreased, but there was no statistically significant difference (P > 0.05), and the PRP + PT group showed decreased VAS and WOMAC scores, increased JOA scores, reduced joint effusion, synovial membrane thickness, and articular cartilage thickness in the knee joint. Moreover, levels of IL-1β and MMP-3 in the synovial fluid decreased, while TGF-β1 levels increased (P < 0.05). No severe adverse reactions were observed in any of the four groups, but the pain rate in the PRP + TP group was significantly lower than PT group, PRP group, and PRP + PT group (P < 0.05). The efficacy of intra-articular injection of PRP combined with exercise therapy in the treatment of knee osteoarthritis is superior to that of single interventions such as simple interventions of HA, PRP injection, and PT. Furthermore, intra-articular injection of PRP combined with exercise therapy demonstrates enhanced effectiveness in improving the inflammatory levels associated with knee osteoarthritis and facilitating the rehabilitation process.

STUDY ON THE ULTRASONOGRAPHIC AND RADIOGRAPHIC FINDINGS OF KNEE OSTEOARTHRITIS PATIENTS AT CAN THO UNIVERSITY OF MEDICINE AND PHARMACY HOSPITAL IN 2022-2023

Background: Knee osteoarthritis is a common disease in the group of bone and joint diseases. The incidence of the disease increases with age, commonly occurs in elderly patients or can also occur in young people. Diagnosis of knee osteoarthritis is mainly based on clinical symptoms combined with radiographs. Currently, ultrasound can be used to examine the damage that occurs in early-stage knee osteoarthritis. In addition, it has the ability to evaluate joint cartilage thickness, detect synovitis, joint effusion,... and abnormal features in other joint diseases of the knee, especially when there are no clinical manifestations or no damage on X-ray images. Objectives: To describe and compare ultrasonographic and radiographic findings in osteoarthritis-affected knee joints. Materials and Methods: A cross-sectional study was conducted on 50 patients and 62 knee joints diagnosed with osteoarthritis according to the American College of Rheumatology (ACR) 1991 criteria. General characteristics, radiographic findings, and ultrasonographic findings in osteoarthritis-affected knee joints of participants were collected at Can Tho University of Medicine and Pharmacy from May 2022 to April 2023. Results: Radiographs showed the most common finding was grade 1 osteophytes. The most common feature found on ultrasound was also grade 1 osteophytes. Medial condyle osteophytes and lateral condyle osteophytes: Grade 1 was the most common finding, with 53.2% and 58.1%. Medial tibial plateau osteophytes and lateral tibial plateau osteophytes: Grade 1 was the most common finding, with 54.8% and 50.0%. Medial compartment joint space narrowing: grade 1 was the most common (41.9%). Lateral compartment joint space narrowing was not found (grade 0) in 64.5%. In addition, ultrasound detected synovitis in patients with knee osteoarthritis, accounting for a fairly high rate of 87.1%. There was moderate agreement between osteophyte and joint space narrowing grading on ultrasound and radiographs. Conclusion: There was moderate agreement between osteophyte and joint space narrowing grading on ultrasound and radiographs. Ultrasound can also detect and evaluate synovitis that may not be seen on radiographs. We recommend using the ultrasonography atlas created for knee osteophyte detection in routine knee ultrasound.

Long-term haplodeficency of DSPP causes temporomandibular joint osteoarthritis in mice

BackgroundExtracellular matrix (ECM) protein malfunction or defect may lead to temporomandibular joint osteoarthritis (TMJ OA). Dentin sialophophoprotein (DSPP) is a mandibular condylar cartilage ECM protein, and its deletion impacted cell proliferation and other extracellular matrix alterations of postnatal condylar cartilage. However, it remains unclear if long-term loss of function of DSPP leads to TMJ OA. The study aimed to test the hypothesis that long-term haploinsufficiency of DSPP causes TMJ OA.Materials and methodsTo determine whether Dspp+/– mice exhibit TMJ OA but no severe tooth defects, mandibles of wild-type (WT), Dspp+/–, and Dspp homozygous (Dspp−/−) mice were analyzed by Micro-computed tomography (micro-CT). To characterize the progression and possible mechanisms of osteoarthritic degeneration over time in Dspp+/– mice over time, condyles of Dspp+/– and WT mice were analyzed radiologically, histologically, and immunohistochemically.ResultsMicro-CT and histomorphometric analyses revealed that Dspp+/– and Dspp−/− mice had significantly lower subchondral bone mass, bone volume fraction, bone mineral density, and trabecular thickness compared to WT mice at 12 months. Interestingly, in contrast to Dspp−/− mice which exhibited tooth loss, Dspp+/– mice had minor tooth defects. RNA sequencing data showed that haplodeficency of DSPP affects the biological process of ossification and osteoclast differentiation. Additionally, histological analysis showed that Dspp+/– mice had condylar cartilage fissures, reduced cartilage thickness, decreased articular cell numbers and severe subchondral bone cavities, and with signs that were exaggerated with age. Radiographic data showed an increase in subchondral osteoporosis up to 18 months and osteophyte formation at 21 months. Moreover, Dspp+/– mice showed increased distribution of osteoclasts in the subchondral bone and increased expression of MMP2, IL-6, FN-1, and TLR4 in the mandibular condylar cartilage.ConclusionsDspp+/– mice exhibit TMJ OA in a time-dependent manner, with lesions in the mandibular condyle attributed to hypomineralization of subchondral bone and breakdown of the mandibular condylar cartilage, accompanied by upregulation of inflammatory markers.

The Correlation between Ultrasonographic Measurements of Femoral Cartilage Thickness and Physical Function in patients with primary knee osteoarthritis

The Correlation between Ultrasonographic Measurements of Femoral Cartilage Thickness and Physical Function in patients with primary knee osteoarthritis

Development and functional evaluation of a hyaluronic acid coated nano-formulation with kaempferol as a novel intra-articular agent for Knee Osteoarthritis treatment

Knee osteoarthritis (OA) involves articular cartilage degradation driven mainly by inflammation. Kaempferol (KM), known for its anti-inflammatory property, holds potential for OA treatment. This study investigated the potential of hyaluronic acid (HA)-coated gelatin nanoparticles loaded with KM (HA-KM GNP) for treating knee OA. KM was encapsulated into gelatin nanoparticles (KM GNP) and then coated with HA to form HA-KM GNPs. Physical properties were characterized, and biocompatibility and cellular uptake were assessed in rat chondrocytes. Anti-inflammatory and chondrogenic properties were evaluated using IL-1β-stimulated rat chondrocytes, compared with HA-coated nanoparticles without KM (HA GNP) and KM alone. Preclinical efficacy was tested in an anterior cruciate ligament transection (ACLT)-induced knee OA rat model treated with intra-articular injection of HA-KM GNP. Results show spherical HA-KM GNPs (88.62 ± 3.90 nm) with positive surface charge. Encapsulation efficiency was 98.34 % with a sustained release rate of 18 % over 48 h. Non-toxic KM concentration was 2.5 μg/mL. In IL-1β-stimulated OA rat chondrocytes, HA-KM GNP significantly down-regulated RNA expression of IL-1β, TNF-α, COX-2, MMP-9, and MMP-13, while up-regulating SOX9 compared to HA GNP, and KM. In vivo imaging demonstrated significantly higher fluorescence intensity within rat knee joints for 3 hours post HA-KM GNP injection compared with KM GNP (185.2% ± 34.1% vs. 45.0% ± 16.7%). HA-KM GNP demonstrated significant effectiveness in reducing subchondral sclerosis, attenuating inflammation, inhibiting matrix degradation, restoring cartilage thickness, and reducing the severity of OA in the ACLT rat model. In conclusion, HA-KM GNP holds promise for knee OA therapy.

Impact of treadmill running on distal femoral cartilage thickness: a cross-sectional study of professional athletes and healthy controls

PurposeThis present study aimed to assess the impact of treadmill running on distal femoral cartilage thickness.MethodsProfessional athletes aged 20 to 40 years with a history of treadmill running (minimum 75 min per week for the past three months or more) and age-, sex-, and body mass index (BMI)-matched healthy controls were recruited. Demographics and clinical features of participants were recorded. Athletes were divided into subgroup 1 with less than 12 months of treadmill running and subgroup 2 with 12 months or more of treadmill running. Distal femoral cartilage thicknesses were measured at the midpoints of the right medial condyle (RMC), right intercondylar area (RIA), right lateral condyle (RLC), left medial condyle (LMC), left intercondylar area (LIA), and left lateral condyle (LLC) via ultrasonography.ResultA total of 72 athletes (mean age: 29.6 ± 6.6 years) and 72 controls (mean age: 31.9 ± 6.7 years) were enrolled. Athletes had significantly thinner cartilages in the RLC (2.21 ± 0.38 vs. 2.39 ± 0.31 cm, p = 0.002), LLC (2.28 ± 0.37 vs. 2.46 ± 0.35 cm, p = 0.004), and LMC (2.28 ± 0.42 vs. 2.42 ± 0.36 cm, p = 0.039) compared with the control group. Furthermore, cartilage thickness was significantly thinner in subgroup 2 athletes compared with the control group in the RLC (2.13 ± 0.34 vs. 2.39 ± 0.31 cm, p = 0.001), LLC (2.22 ± 0.31 vs. 2.46 ± 0.35 cm, p = 0.005), and LMC (2.21 ± 0.46 vs. 2.42 ± 0.36 cm, p = 0.027); however, subgroup 1 athletes did not have such differences. There was a weak negative correlation between total months of treadmill running and cartilage thickness in the RLC (r = − 0.0236, p = 0.046) and LLC (r = − 0.0233, p = 0.049). No significant correlation was found between the distal femoral cartilage thickness at different sites and the patients’ demographic features, including age, BMI, speed and incline of treadmill running, and minutes of running per session and week (p > 0.05).ConclusionCompared with healthy controls, professional athletes with a history of long-term high-intensity treadmill running had thinner femoral cartilages. The duration (months) of treadmill running was weakly negatively correlated with distal femoral cartilage thickness. Longitudinal studies with prolonged follow-ups are needed to clarify how treadmill running affects femoral cartilage thickness in athletes.

Effects of sex differences on osteoarthritic changes after anterior cruciate ligament reconstruction in rats

The prevalence of primary osteoarthritis is higher in females than males. However, it remains unclear if there are sex differences in the incidence of post-traumatic osteoarthritis after anterior cruciate ligament (ACL) reconstruction. In this study, we aimed to investigate the effects of sex on osteoarthritic changes after ACL reconstruction using an animal model. Rats were divided into the following four groups: male control, male ACL reconstruction, female control, and female ACL reconstruction. ACL reconstruction surgery was performed on the right knees of rats in the ACL reconstruction groups, while rats in the control groups did not undergo knee surgery. At 1, 4, and 12 weeks after surgery, cartilage degeneration in the medial tibial plateau and osteophyte formation in the proximal tibia were histologically assessed. After ACL reconstruction, an increase in the Mankin score, cartilage fissures, and osteophyte formation were detected within 12 weeks in both male and female rats, with similar degrees of these changes between males and females. However, changes in cartilage thickness and chondrocyte density after ACL reconstruction differed between males and females. Cartilage thickening was observed in male rats but not in female rats. The increase in chondrocyte density in the anterior region was detected in both males and females but was more pronounced in female rats. In conclusion, osteoarthritic changes were observed after ACL reconstruction in both male and female rats, but differences in changes in cartilage thickness and chondrocyte density were observed between males and females.

Gerdy's tubercle as a novel anatomical landmark for the proximal tibial cut in total knee arthroplasty.

This study aimed to explore the use of Gerdy's tubercle (GT) as an innovative and dependable anatomical landmark for the proximal tibial cut in total knee arthroplasty (TKA) in cases with extensive knee degeneration. One hundred dry tibia bones and 10 formalin-fixed cadaveric knee specimens of both sexes were examined. A Zimmer NexGen tibial cutting guide and a Mitutoyo digital caliper were utilized to align the guide with the tibia's mechanical axis. The procedure was replicated on cadaver knees using a standardized medial parapatellar arthrotomy approach. Measurements included the distance from GT superior border to the resection line and the length of the tibia. A radiological study involving magnetic resonance imaging examinations of 48 patients, which were evaluated focusing on the upper border of GT and the least degenerated segment of the posterolateral part of the lateral tibial condyle, was conducted. Anatomical measurements of GT and proximal tibial areas in 110 specimens showed slight but consistent variations with cadaver measurements. Magnetic resonance imaging analysis of 48 patients revealed notable sex differences in the distance between the superior border of GT and the tibia's posterolateral surface. There was also a significant negative correlation between the distance from GT to the posterolateral corner and cartilage thickness. Proper alignment in TKA is crucial for success, but identifying an extra-articular landmark for horizontal tibial resection remains challenging, particularly in severely arthritic knees. This study introduces GT as a novel anatomical landmark for TKA, offering a more reliable reference for achieving desired joint levels in knees with significant degenerative changes.

Numerical analysis of a poroelastic cartilage model: Investigating the influence of changing material properties in osteoarthritis

Several changes occur in both the cartilage's material properties and anatomical structure as osteoarthritis progresses. Unlike most numerical studies that solely consider individual changes, our study aimed to understand the impact on cartilage mechanics by considering the combined effect of material properties and cartilage thickness varied with osteoarthritis progression. In total, 3 three-dimensional finite element models, representing the intact, early, and late osteoarthritis conditions, were developed to simulate a load-bearing area in the knee. The articular cartilage was modelled as fluid-saturated linear biphasic poroelastic to incorporate solid-fluid interaction. All models underwent prolonged creep (50 N) and relaxation (0.3 mm) analyses for 600 s. In the early stage of osteoarthritis, the tibial cartilage demonstrated an overall stiffer behaviour attributed to cartilage swelling despite decreased stiffness at the material level. On the other hand, in the late stage of osteoarthritis, the decrease in cartilage thickness led to increased knee deformation. Additionally, increased permeability resulted in accelerated fluid exudation across all osteoarthritis models, and the elevation in void ratio further intensified fluid pressure within the cartilage to a higher magnitude. Furthermore, these changes collectively influenced both the magnitude and distribution of the outcomes. A holistic understanding of the material properties altered in osteoarthritis may contribute to a better understanding of the mechanical performance of cartilage during disease progression.

Evaluation of the consistency of the MRI- based AI segmentation cartilage model using the natural tibial plateau cartilage.

The study aims to evaluate the accuracy of an MRI-based artificial intelligence (AI) segmentation cartilage model by comparing it to the natural tibial plateau cartilage. This study included 33 patients (41 knees) with severe knee osteoarthritis scheduled to undergo total knee arthroplasty (TKA). All patients had a thin-section MRI before TKA. Our study is mainly divided into two parts: (i) In order to evaluate the MRI-based AI segmentation cartilage model's 2D accuracy, the natural tibial plateau was used as gold standard. The MRI-based AI segmentation cartilage model and the natural tibial plateau were represented in binary visualization (black and white) simulated photographed images by the application of Simulation Photography Technology. Both simulated photographed images were compared to evaluate the 2D Dice similarity coefficients (DSC). (ii) In order to evaluate the MRI-based AI segmentation cartilage model's 3D accuracy. Hand-crafted cartilage model based on knee CT was established. We used these hand-crafted CT-based knee cartilage model as gold standard to evaluate 2D and 3D consistency of between the MRI-based AI segmentation cartilage model and hand-crafted CT-based cartilage model. 3D registration technology was used for both models. Correlations between the MRI-based AI knee cartilage model and CT-based knee cartilage model were also assessed with the Pearson correlation coefficient. The AI segmentation cartilage model produced reasonably high two-dimensional DSC. The average 2D DSC between MRI-based AI cartilage model and the tibial plateau cartilage is 0.83. The average 2D DSC between the AI segmentation cartilage model and the CT-based cartilage model is 0.82. As for 3D consistency, the average 3D DSC between MRI-based AI cartilage model and CT-based cartilage model is 0.52. However, the quantification of cartilage segmentation with the AI and CT-based models showed excellent correlation (r = 0.725; P values < 0.05). Our study demonstrated that our MRI-based AI cartilage model can reliably extract morphologic features such as cartilage shape and defect location of the tibial plateau cartilage. This approach could potentially benefit clinical practices such as diagnosing osteoarthritis. However, in terms of cartilage thickness and three-dimensional accuracy, MRI-based AI cartilage model underestimate the actual cartilage volume. The previous AI verification methods may not be completely accurate and should be verified with natural cartilage images. Combining multiple verification methods will improve the accuracy of the AI model.

Morphometry of the thyroid cartilage, epiglottis and piriform sinus: An anatomical study.

The goal was to measure the piriform sinus, epiglottis, and thyroid cartilage in our sample population. This study included 22 adult embalmed cadavers available in the Department of Anatomy. Dimensions were measured using a digital Vernier caliper. The mean height of the thyroid laminae was 27 ± 1.4 mm at the right side and 25.5 ± 1.4 mm at the left side. Mean width of the thyroid lamina was 27.1 ± 1.3 mm at the right side and 27.4 ± 0.9 mm at the left side. The mean thickness of thyroid cartilage was found to be 4.4 ± 0.4 mm and 3.9 ± 0.5 mm over the right and left sides. The mean length, width and thickness of the epiglottis were 29.1 ± 0.5 mm, 22.2 ± 0.6 mm and 2.6 ± 0.3 mm correspondingly. The height, width and thickness of the right piriform sinus were 25 ± 0.5 mm, 14.2 ± 0.5 mm and 12.6 ± 0.5 mm, the same parameters were 25.3 ± 1.3 mm, 15.1 ± 0.7 mm and 13.3 ± 0.4 mm for the left side. The height and thickness of the thyroid cartilage were greater on the right side than on the left side (p<0.05). It was statistically observed that the width and thickness were greater on the left side than on the right side (p < 0.05). The data about the height, width and thickness of the thyroid cartilage, epiglottis and piriform sinus are essential during the laryngeal and other neck surgeries. They guide in the preoperative positioning, predicting the difficulty of intraoperative exposure and retractor pulling.

Associations between Body Mass Index, Gait Mechanics and Trochlear Cartilage Thickness in Those with ACL Reconstruction.

High body mass index (BMI) is a strong predictor of posttraumatic osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR). Altered gait mechanics are independently affected by BMI and ACLR, and influence OA risk. Yet, evidence directly assessing the impact of high BMI on gait or cartilage characteristics after ACLR are limited. Here, we evaluated if high BMI moderates associations between gait and trochlear cartilage structure in individuals with ACLR. Treadmill walking biomechanics were evaluated in 40 normal BMI and 24 high BMI participants with ACLR at self-selected speeds. Normalized and absolute peak and cumulative loads (i.e., impulse) were extracted for peak knee flexion and adduction moments (KFM, KAM) and vertical ground reaction force (GRF). Medial and lateral femoral cartilage thickness and medial/lateral thickness ratios were assessed via ultrasound. Those with ACLR and high BMI walked with reduced normalized peak vertical GRFs, and greater absolute peak and cumulative loads compared with normal BMI individuals with ACLR. Those with ACLR and high BMI also exhibited thinner cartilage and greater medial/lateral ratios in ACLR limbs compared with contralateral limbs whereas normal BMI individuals with ACLR exhibited thicker ACLR limb cartilage. Lastly, greater peak KAM and KAM cumulative load were associated with thicker lateral cartilage and lesser medial/lateral thickness ratios, but only in the high BMI group. We observed those with high BMI after ACLR exhibited trochlear cartilage structural alterations not observed in normal BMI patients, whereas differential associations between loading outcomes and cartilage thickness in ACLR knees were observed between groups. Those with high BMI after ACLR may require different therapeutic strategies to optimize joint health in this subset of patients.

Numerical study of osteophyte effects on preoperative knee functionality in patients undergoing total knee arthroplasty.

Osteophytes are routinely removed during total knee arthroplasty, yet the preoperative planning currently relies on preoperative computed tomography (CT) scans of the patient's osteoarthritic knee, typically including osteophytic features. This complicates the surgeon's ability to anticipate the exact biomechanical effects of osteophytes and the consequences of their removal before the operation. The aim of this study was to investigate the effect of osteophytes on ligament strains and kinematics, and ascertain whether the osteophyte volume and location determine the extent of this effect. We segmented preoperative CT scans of 21 patients, featuring different osteophyte severity, using image-based active appearance models trained to identify the osteophytic and preosteophytic bone geometries and estimate the cartilage thickness in the segmented surfaces. The patients' morphologies were used to scale a template musculoskeletal knee model. Osteophytes induced clinically relevant changes to the knee's functional behavior, but these were variable and patient-specific. Generally, severe osteophytic knees significantly strained the oblique popliteal ligament (OPL) and posterior capsule (PC) relative to the preosteophytic state. Furthermore, there was a marked effect on the lateral collateral ligament and anterolateral ligament (ALL) strains compared to mild and moderate osteophytic knees, and concurrent alterations in the tibial lateral-medial translation and external-internal rotation. We found a strong correlation between the OPL, PC, and ALL strains and posterolateral condylar and tibial osteophytes, respectively. Our findings may have implications for the preoperative planning in total knee arthroplasty, toward reproducing the physiological knee biomechanics as close as feasibly possible.

Capsular attachment on the anterosuperior femoral head-neck junction: A hypothesis about femoroacetabular impingement.

Femoroacetabular impingement (FAI), characterized by a pathological contact between the proximal femur and acetabulum, is a common precursor of hip osteoarthritis. Cam morphology is a bony prominence that causes FAI and frequently forms on the anterosuperior femoral head-neck junction. Despite anatomical consensus regarding the femoral head-neck junction as a boundary area covered by the articular cartilage and joint capsule, it remains unclear whether the joint capsule is continuous with the anterosuperior articular cartilage. For the anatomical consideration of cam morphology formation, this study aimed to investigate the histological characteristics of the capsular attachment on the anterosuperior femoral head-neck junction, particularly focusing on the presence or absence of continuity of the joint capsule to the articular cartilage. A total of 21 anterosuperior regions (seven hips each for the 12:00, 1:30, and 3:00 positions) from seven hips (three males and four females; mean age at death, 68.7 years) were histologically analyzed in this study for quantitative evaluation of the capsular thickness using histological sections stained with Masson's trichrome, as well as qualitative evaluation of the capsular attachment. The present study showed that the joint capsule, which folded proximally to the femoral head-neck junction from the recess, exhibited a blend of the fibrous and synovial regions. Notably, it not only continued with the superficial layer of the articular cartilage, but also attached to the articular cartilage via the fibrocartilage. This continuous region was relatively fibrous with dense connective tissue running in the longitudinal direction. The capsular thickness at the recess point (mean, 1.7 ± 0.9 mm) and those at the distal end of the articular cartilage (0.35 ± 0.16 mm) were significantly greater than the control value for the most superficial layer thickness of the articular cartilage (0.019 ± 0.003 mm) (Dunnett's T3, both p-value <0.001). Based on the fibrous continuity between the joint capsule and articular cartilage and its thickness, this study suggests the anatomical possibility that some mechanical stress can be transmitted from the joint capsule to the articular cartilage at the frequent sites of cam morphology.